כנס העמותה הישראלית למדעי הימים 2011 אפריל 11-12

‫כנס העמותה הישראלית למדעי הימים‬
‫‪ 11-12‬אפריל ‪2011‬‬
‫באירוח חברת החשמל‬
‫חוות חפציבה ותחנת "אורות רבין"‬
‫שלום וברכה למשתתפי הכנס‪,‬‬
‫מצ"ב תכנית כנס העמותה הישראלית למדעי הימים לשנת ‪ 2011‬בנושא "אדם והסביבה המימית" ובהמשכה‬
‫מקבץ התקצירים של ההרצאות והכרזות המוצגות בכנס (ע"פ סדר הא'‪-‬ב')‪ .‬השנה אנו מודים לחברת החשמל‬
‫לישראל על אירוחם במתקניהם בחוות חפציבה ובתחנת "אורות רבין"‪.‬‬
‫היום הראשון מוקדש כולו להרצאות‪ ,‬כאשר אנו מתכבדים לפתוח את הכנס במסורת חדשה ובה מוענק פרס‬
‫מפעל חיים לתרומה חשובה בתחום מדעי הימים‪ .‬השנה אנו מעניקים פרס זה לפרופסור לב פישלזון (אונ' ת"א)‪,‬‬
‫מחלוצי התחום המרבה בעשייה גם היום (ראו סיכום קצר של פעליו הרבים בהמשך)‪ .‬המושב המרכזי השנה‬
‫עוסק במשק המים הישראלי ובו הרצאות מוזמנות על הכנרת מפרופ' תמר זהרי (מעבדה לחקר הכנרת –‬
‫חיא"ל)‪ ,‬על מערך ותכניות ההתפלה בישראל מאברהם טנא (רשות המים) ועל השפעות ההתפלה על הסביבה‬
‫החופית מד"ר נורית קרס (חיא"ל)‪.‬‬
‫תרומת חברי העמותה והסטודנטים בתחומים השונים הינה גדולה ומורחבת השנה‪ .‬במהלך ‪ 2‬ימי הכנס יתקיימו‬
‫‪ 58‬הרצאות במושבים מקבילים ובנושאים מגוונים‪ :‬גיאולוגיה‪ ,‬סדימנטולוגיה וביאוגאוכימיה של מערכות‬
‫אקווטיות טבעיות; גישות חדישות במדעים אקווטים; פיזיקה ומודלים של מערכות אקווטיות; אלמוגים‪,‬‬
‫קלציפיקציה והחמצת אוקיאנוסים; דגים ומינים פולשים; ואדם והסביבה הימית כאשר ידונו גם סוגיות בשימור‬
‫וניהול סביבות חופיות‪ .‬בנוסף להרצאות מוקדש מושב ל ‪ 18‬כרזות בנושאים שונים‪.‬‬
‫בנוסף למושבי ההרצאות והכרזות הוספנו השנה מגוון פעילויות המאפשר חוויות נוספות במסגרת הכנס‪ :‬ארוחת‬
‫ערב על החוף בשדות ים‪ ,‬טיול שחרית לאורך נחל חדרה המשוקם וסיורים מודרכים באתר תחנת הכח "אורות‬
‫רבין" של חברת החשמל לישראל ובמפעל ההתפלה ‪ OMI-WATER‬הצמוד אליו‪.‬‬
‫עד כה כ ‪ 50%‬מהנרשמים ומהמרצים הינם סטודנטים לתארים מתקדמים‪ .‬ברצוני לציין שזוהי השנה השנייה‬
‫שבה יושבי ראש המושבים השונים הינם רובם סטודנטים מהמוסדות השונים הלוקחים חלק פעיל בכנס‬
‫ובארגונו‪ .‬כמו בכל שנה‪ ,‬אנו מעודדים את השתתפות הסטודנטים ומחלקים פרסים למאמר‪V ,‬הרצאה והכרזה‬
‫הטובים אשר נבחרים ע"י צוות שופטים לפני ובמשך הכנס‪.‬‬
‫אנו מאחלים שהכנס אכן יהיה פרודוקטיבי ומהנה ושתחזרו בשנית בשנה הבאה‪.‬‬
‫וועד חברי העמותה‪:‬‬
‫אילנה ברמן‪-‬פרנק‬
‫דני גולני‬
‫ענת גלזר‬
‫בברלי גודמן‬
‫סוון בר‬
‫אלווארו ישראל‬
‫יוני שרון‬
‫תוכנית הכנס השנתי של העמותה הישראלית למדעי הימים –‪ 11-12‬אפריל ‪ .2011‬פרוט‬
‫ההרצאות במושבים בהמשך לתכנית הכללית‬
‫תאריך ‪/‬שעה‬
‫יום שני ‪11.4.2011‬‬
‫‪0800-0930‬‬
‫פעילות‬
‫מיקום ‪ -‬חוות חפציבה‬
‫התכנסות ורשום – קפה וכיבוד‬
‫מיקום הפעילות‬
‫חוות חפציבה‬
‫‪0930-0940‬‬
‫מושב פתיחה ‪ .‬ברכות – אילנה ברמן‪-‬פרנק‬
‫פרס מפעל חיים‪ .‬פרופ' לב פישלזון‬
‫הרצאה טקטוניקת לוחות ("נדידת יבשות")‬
‫ואסטרטגיות רביה בדגים‪ :‬גונדוונה ומסעות הקרנוניים‬
‫מושב ‪ + II‬מושב ‪III‬‬
‫הפסקת קפה‬
‫מושב ‪ . I‬מרכזי‬
‫משק המים בישראל‪ :‬כנרת והתפלה‬
‫הרצאה ‪ .I‬תנודות מפלסי אגם גדולות מהטבעי ‪-‬‬
‫תורמות לפגיעה באיכות המים ‪ .‬תמר זהרי‬
‫הרצאה ‪ .II‬משק המים וההתפלה בישראל‪.‬‬
‫אברהם טנא‬
‫הרצאה ‪ .III‬השפעת מתקן התפלה על הסביבה‬
‫הימית‪ .‬מחקר שדה בחוף הים תיכוני של ישראל‪.‬‬
‫נורית קרס‬
‫הפסקת צהריים‪.‬‬
‫סיור‪+‬סרט באתר המשוקם של חוות חפציבה‬
‫מושב פוסטרים ‪ +‬קפה‬
‫מושב ‪ + IV‬מושב ‪V‬‬
‫הפסקת קפה‬
‫מושב ‪ + VI‬מושב ‪VII‬‬
‫פיזור‬
‫ארוחת ערב על החוף מול השקיעה בשדות ים‪.‬‬
‫ביקור וסרט באקואושן – דניאל שפר‬
‫כתה ‪31‬‬
‫כתה ‪31‬‬
‫‪0940-1010‬‬
‫‪1015-1130‬‬
‫‪1130-1145‬‬
‫‪1145-1215‬‬
‫‪1215-1245‬‬
‫‪1245-1300‬‬
‫‪1300-1400‬‬
‫‪1400-1500‬‬
‫‪1500-1700‬‬
‫‪1700-1715‬‬
‫‪1715-1845‬‬
‫‪1845‬‬
‫‪1900‬‬
‫יום שלישי ‪12.4.11‬‬
‫‪0630-0800‬‬
‫טיול נחל חדרה המשוקם עד לחוף‬
‫‪0800-0830‬‬
‫התכנסות ‪ +‬קפה‪.‬‬
‫אתר תחנת הכח אורות רבין חדרה‬
‫מושב ‪ – VIII‬אדם וים‬
‫‪0930-1030‬‬
‫‪1030-1050‬‬
‫‪1050-1145‬‬
‫מושב מקביל ‪ IX‬ו ‪X‬‬
‫הפסקת קפה‬
‫אסיפת עמותה ‪ +‬בחירות ‪ +‬פרסים לסטודנטים‬
‫‪/‬דברי סיכום‬
‫סקירה כללית לקראת הסיורים בחברת החשמל‬
‫גיורא דקל –מנהל אתר תחנת הכח‬
‫ארוחת צהריים‬
‫‪1315-1430‬‬
‫‪1430-1600‬‬
‫סיור בתחנת הכח‬
‫סיור במתקן ההתפלה‬
‫‪0830-0930‬‬
‫‪1145-1215‬‬
‫‪1215-1315‬‬
‫***הסיור בתחנת הכח ובמתקן ההתפלה לנרשמים מראש‬
‫פיזור‬
‫‪1600‬‬
‫כתה ‪ + 31‬כתה נוספת‬
‫כתה ‪31‬‬
‫כתה ‪31‬‬
‫כתה ‪31‬‬
‫כתה ‪2‬‬
‫כתה ‪ + 2‬כתה ‪31‬‬
‫כתה ‪ + 2‬כתה ‪31‬‬
‫שדות ים‬
‫**יש להירשם מראש בבוקר‬
‫הכנס‬
‫אתר תחנת הכח אורות רבין‬
‫חדרה‬
‫אתר תחנת הכח אורות רבין‬
‫חדרה‬
‫אתר תחנת הכח אורות רבין‬
‫חדרה‬
‫**יש להרשם מראש‬
‫אתר תחנת הכח אורות רבין‬
‫חדרה‬
‫תכנית מפורטת של כנס העמותה הישראלית למדעי הימים‬
III ‫ ו‬II ‫ מושבים‬.2011 ‫ אפריל‬11 ‫יום שני‬
1000-1115
‫גישות חדשות במדעים אקווטים‬
III ‫מושב‬
– ‫מערכות אקווטיות טבעיות‬
‫גאולוגיה וסדימנטולוגיה‬
‫יו"ר – עמית לרנר‬
‫זמן ההרצאה‬
‫ שי אורון‬:‫יו"ר‬
13 ‫כתה‬
‫ניווט ע"י קיטוב אור בים‬
II ‫מושב‬
2 ‫כתה‬
‫עמית לרנר‬
‫פתיחתם וסגירתם של האגנים בשולי‬
‫האוקיאנוס – ניסויים במודל אנלוגי‬
‫יוסי מרט‬
1015-1030
‫חיים‬-‫תמר גיא‬
‫הערכת השינויים מעשי ידי אדם‬
‫ השנים‬60 ‫ במהלך‬,‫בבריכת נור‬
‫ באמצעות הביוטה הגירית‬,‫האחרונות‬
-‫אהובה אלמוגי‬
‫לבין‬
1030-1045
Zooming into algal blooms- The
chemical arms race in host-virus
interactions in the ocean
‫אסף ורדי‬
-‫אורית חיימס‬
‫קפצן‬
1045-1100
Response of Prochlorococcus
Ecotypes to co-culture with DIVERSE
marine bacteria
‫דניאל שר‬
The effect of the Nile and the
Shafdan outlet on benthic
fauna of the Israeli shelf:
foraminifera and mollusca
assemblages
‫גיאומורפולוגיה וסדימנטולוגיה‬
‫ימי אכזיב‬-‫באזור הקניון התת‬
‫הלק‬-‫לנה אשקר‬
1100-1115
Precambrian natural injectors as a novel
topical platform for systemic drug
delivery
‫תמר לוטן‬
‫צופית מור‬
1115-1130
Using molecular tools for resolving
patterns of zonation
‫סביבתיים בתקופת‬-‫שינויים פליאו‬
‫ההולוקן על סמך רקורד סדימנטרי‬
‫מול חופי ישראל‬
.2011 ‫ אפריל‬11 ‫יום שני‬
)‫ (פרוט בסוף‬1400-1500 ‫מושב כרזות‬
1500-1700 V ‫ ו‬IV ‫מושבים‬
‫החמצת אוקיאנוסים‬/‫קלציפיקציה‬/‫אלמוגים‬
V ‫מושב‬
13 ‫כתה‬
‫יו"ר – יסמין‬
‫גבאי‬
‫מיכל שורק‬
The rhythmicity of photosynthesis in
symbiodinium, the coral
endosymbiotic algae.
Oxygen evolution and corals
Decreased calcification of a coral reef
flat in the Great Barrier Reef due to
ocean acidification
‫דני צ'רנוב‬
‫ג'ק סילברמן‬
‫פיזיקה ומודלים של מערכות‬
‫אקווטיות‬
2 ‫כתה‬
On the spatial distribution of
ocean surface currents
Deducing an upper bound to
the horizontal eddy
diffusivity using a stochastic
Lagrangian model
Modeling the effect of
nutrient loads (N,P) and
water levels on water
quality
IV ‫מושב‬
‫זמן ההרצאה‬
‫יו"ר – אלי‬
‫ביטון‬
‫יוסף אשכנזי‬
1500-1515
‫דניאל‬
‫קרלסון‬
1515-1530
‫יעל גלבוע‬
1530-1545
‫גל דישון‬
Underwater light field variation in high
latitude coral reefs: a case study from
the Gulf of Aqaba.
‫יסמין גבאי‬
The effects of ocean acidification on
soft corals from the family Xeniidae
Differential morphological features of
two Dendronephthya soft coral species
suggest differences in feeding niches
Sea water vacuolization dynamics in
benthic foraminifera studied with the
fluorescent probe Calcein
A New Method for Precise
Measurements of Dissolved Inorganic
Carbon
‫מיכל גרוסוביץ‬
‫יעל לוינסון‬
Modeling of Morphological
Processes around Marine
Facilities Located along the
Israeli Shore
Mesoscale variability of
shallow water medium and
acoustical monitoring of
these perturbations
‫הדמיה ממוחשבת של האקולוגיה‬
‫של אוכלוסיות פלנקטוניות במזרח‬
‫האגן הלבנטיני‬
The general circulation of
the Gulf of Eilat/Aqaba
revisited:
The interplay between the
exchange flow through the
Straits
of Tiran and surface fluxes
‫מיכאל‬
'‫סלדקוויץ‬
1545-1600
‫בוריס‬
‫קצנלסון‬
1600-1615
‫יאיר סוארי‬
1615-1630
‫אלי ביטון‬
1630-1645
‫אייל וורגפט‬
1645-1700
‫ הפסקת קפה‬1630-1645
1715-1830
‫דגים ומינים פולשים‬
VII ‫ ו‬VI ‫ מושבים‬.2011 ‫ אפריל‬11 ‫יום שני‬
VII ‫מושב‬
‫יו"ר – דור אדליסט‬
‫מערכות אקווטיות טבעיות – ביוגאוכימיה‬
‫ניר שטרן‬
Keep and Touch – Dust and mineral iron
utilization by the marine diazotroph
Trichodesmium
Stable C and N isotopes in Lake
Kinneret food web: past and present
2 ‫כתה‬
Spatial distribution of Red Sea
migrant fishes along the Eastern
Mediterranean
‫פאונת הטפילים במיני דגים פולשים‬
‫ הנתון תחת‬,‫ומקומיים במזרח הים התיכון‬
‫השפעת השינוי האקלימי‬
"‫אוכלוסיות הצדפה "תמר הים‬
Lithophaga lithophaga ‫בחוף הים‬
‫ ניצול בקשוות הצדפות‬:‫תיכוני הישראלי‬
‫המהגרות‬spinosus Spondylus -‫ו‬
Chama pacifica
‫ביולוגיה ואקולוגיה של בינון הירדן‬
Nemacheilus jordanicus(
The Ecological and Economical
Effect of Recreational Fishing in
the Eastern Basin of the
Mediterranean Sea
VI ‫מושב‬
‫יו"ר – מקס‬
‫רובין‬
‫זמן ההרצאה‬
‫מקס רובין‬
1715-1730
‫ארם גודווין‬
1730-1745
‫רותם גולן‬
1745-1800
-‫גיא סיסמא‬
‫ונטורה‬
1800-1815
‫גיל רילוב‬
1815-1830
13 ‫כתה‬
‫יעל קלופמן‬
‫עתרת שבתאי‬
‫בת שבע רוטמן‬
‫דורון שולץ‬
Seasonal variability in fractionation of
sulfur isotopes in a freshwater marsh –
Hula nature reserve
Seasonal variability of oxygen and
carbon stable isotopes, alkalinity and pH
in the Vermetid reef surrounding:
Implications for the reconstruction of
past.
An ecosystem unfolds: spatiotemporal
biodiversity patterns on Israeli
Mediterranean vermetid reefs
‫רשימת כרזות‬
Daniel
Itay
Dor
Shai
Hadar
Beverly
Gal
Mor
Ruth
Yael
Yael
Shai
Noa
Aharon
Marina
Uri
Amir
Jack
How useful are progressive vector diagrams for studying coastal ocean
Carlson
transport?
Cohen
Does light or photosynthesis enhance calcification in symbiotic corals?
Edelist
Red Sea fish in the Mediterranean, as seen through trawl catches in Israel
Mechanisms for surface chlorophyll pattern formation: satellite based examples
Efrati
from the Eastern Mediterranean
Elyashiv
Holocene Zevulun Plain wetlands: Evolution and implications
Marine Sedimentological Signatures from the 2010 Winterstorm Event in
Goodman Caesarea
Quaternary sequences of fringing reef development along the northern shelf of
Hartman
the Gulf of Eilat/Aqaba
Sediment reworking events in submarine cores from the Northern Gulf of
Kanari
Aqaba-Eilat
Sphingolipids in phytoplankton bloom termination: from gene prediction to
Khait
cellular mechanism and detection of viral infection in the ocean
Kiro
Processes controlling radium and radon activities in the Dead Sea
Calcein incorporation into the shells of foraminifera: A new tool to study
Levenson biomineralization processes in foraminifera
Litni
‫ באתר "אורות רבין" – חדרה‬,‫פרוייקט שיקום וצביעת גשר ומזח פריקת הפחם‬
Nakar
"‫ ניתוח כלכלי"מדוזות ברשת‬:‫השפעתן של מדוזות על ענף הדיג‬
Oceanographic equipment used in Dead Sea explorations in the middle of the
Oren
19th century
Polak
Influence of radiation levels on coral bleaching in the age of global warming
Filling up the shelf – a sedimentary response to the last interglacial sea rise
Schattner imaged in sub-meter resolution off northern Israel
Yacht Tourism as a Generator for Economic Development in Small Coastal
Shani
Communities
Silverman Community calcification of the One Tree Island reef: a 40 year perspective
Margarita Zarubin
Depth keeping by swimming against the flow in zooplankton: adaptive benefits
and ecological implications
‫ אתר תחנת הכח "אורות רבין" חדרה‬12.4.2011 '‫יום ג‬
VIII ‫מושב‬
‫יו"ר – דני גולני‬
‫מושב משותף‬
Dead Sea - Red Sea and Dead Sea - Mediterranean Sea connections on 17th-19th
century maps of the Holy Land.
Deep Sea Phenomena in the Israeli Mediterranean: Research and Implications
.‫יחסי הגומלין בין המתקנים הימיים של חברת החשמל והסביבה הימית‬
VIII ‫מושב‬
‫אהרון אורן‬
‫זמן ההרצאה‬
0830-0845
‫יצחק מקובסקי‬
‫ענת גלזר‬
0845-0900
0900-0930
‫ מושב‬IX
‫יו"ר – פיליפ‬
‫נימוי‬
‫רונן אלקלאי‬
‫זמן ההרצאה‬
-‫שמרית פרקול‬
‫פינקל‬
0945-1000
‫פיליפ נימוי‬
1000-1015
‫אשר גיתאי‬
1015-1030
IX -‫ ו‬X ‫מושבים‬
‫אדם והסביבה הימית‬
Transparent exopolymer particles;
microbial
shuttles
expediting
biofilm formation in desalination
facilities
Rapid sand filtration in a newly
operated
SWRO
desalination
facility, hints of biodegradation
X ‫מושב‬
‫יו"ר – עדו‬
‫בר זאב‬
‫זאב‬-‫עדו בר‬
‫נטליה‬
‫בלקין‬
Pollution effects on the benthic
intertidal algal flora along the
Israeli Mediterranean shores
‫רזי הופמן‬
‫השינוי במאספי פורמיניפרים בנתונים‬
- ‫בתגובה לפינוי כלובי הדגים במפרץ אילת‬
‫עקבה‬
‫שי אורון‬
‫שימור וניהול סביבות חופיות‬
Clean Coast Program – a
Tool for Preserving the
Economic Value of the
Israeli Coast
Sustainable management of
urban marine structures:
results from the Adriatic Sea
and possible applications for
Israeli coastlines
Combining Science and
Leisure: The Role of Marine
Exploration Tourism for
Different Stakeholder Groups
‫ ממטרד‬- ‫הפרשות דגים באילת‬
‫סביבתי למנוף כלכלי‬
0930-0945
‫פרס מפעל חיים ניתן השנה לפרופסור לב פישלזון‬
‫פרס מפעל חיים ניתן השנה לפרופסור לב פישלזון‬
Professor Lev Fishelson (LF) – summary written by A. Abelson.
From the onset of his scientific activity at the Margolin Biology Center at the
University Institute of Zoology at Abu Kabir, and later in the Department of Zoology at
Tel Aviv University, LF believed that, as a Zionist scientist, his duties should focus not
only on academic affairs, but also on outreach to the people of his country. With this
belief in mind, he began to publish popular papers in Hebrew, present talks on the radio
and publish books on Israeli nature. Examples of these are his books "Life around the
Dead Sea", “The Mysteries of the Red Sea", "Animal Corner in the School" and
"Aquariums in School". Thus, in addition to his peer-reviewed scientific publications
(which today number more than 200, including five papers in Nature and one in Science),
LF has published over 100 “popular” papers in Hebrew (in "Teva v’Aretz", "Adam
v'Svivato” and "Sade") as well as numerous publications in newspapers, all aimed to
popularize nature and to protect the nature and biological assets of Israel.
In conjunction with his academic activities at the University, LF presented the first
radio-transmitted University Course on marine biology as organized by ZAHAL, and has
been teaching zoology and anatomy once a week for 14 years at the Kibbutzim Teacher’s
Seminar. LF was among the establishers of The Israel Ecological Society, the umbrella
organization "Adam v’Hasviva" (Man and Environment), the Society of Underwater
Activity, and acted as an Editor of Encyclopedia L'hai v'Lazomeach (Animal and Plant
Encyclopedia) that brought Israel’s nature to some 60,000 homes. Other extracurricular
outreach activities include serving for many years on the Board of the Hevra l’Haganat
Hateva (Society for the Protection of Nature) and the Israel Ecological and Zoological
Societies. LF has provided professional advice to many government offices including that
of Shimon Peres (then Minister of Transportation) on the ecology of littorals, to Roni
Milo (first Minister of Environment), the Ministry of Education for establishment of the
Underwater Observatory, and to the Ministry of Tourism and Education for establishment
of the Dolphin Reef in Eilat, and he was a member of the committee for the new
biological curriculum for reform in schools (1973). In his academic capacity, LF was
responsible for the education of many undergraduate and graduate students including
now established professors such as Yossi Loya, Menachem Goren and Zvi Lifshitz
(TAU), Ehud Spanier (Haifa U),
and Muki Spigel (BGU). Prof. Fishelson's activities earned him many honors around the
world including: Honorary Member of the Israeli Ecological Society (1989), Doctor
Honorus Causa of the University in Johannesburg (1989), Magen of the Minister of
Eichut haSviva (1997), Member of the Academy of Science in Erfurt, Germany (1995),
Honorary Member of the Israeli Zoological Society (1994), a special recognition by the
Prime Minister Yitzchak Rabin for contribution to Israeli culture 1987, and an honorary
fellow of IIO, Eilat (1996).
Amongst the many Pioneering studies LF investigated are:
 Grasshoppers as users of plant toxins to produce defense mechanisms (1966-1968);
Social control of sex-change in coral reef fishes - this opened the way for a new topic in
fish studies (1970);
 First study to descrobe the communities of soft bottom habitats in the Red Sea (1972);
 Hybridization of Tilapias as a new mean for aquaculture (1965-1972) - today the
established world-wide method in this field;
 Aquaculture in the Negev and Arava with use of subterranean brackish waters developing a branch of desert fish farming;
 Discovery and description of a mega-bacterium symbiotic relations in guts of surgeon
fishes;
The first attempt to study pollution effects in a total environment - Akko Shoreline
and another invited study for the Ashdod region.
Abstract List (in Alphabetical Order)
Clean Coast Program – a Tool for Preserving the Economic Value of the Israeli
Coast
Alkalay Ronen1 and Pasternak Galia2
1
Marine and Coastal Environment Division (MCED), Ministry of Environmental
Protection, Israel.
2
Marine and Coastal Environment Division (MCED), Ministry of Environmental
Protection, Israel.
The importance of open spaces in general and the coastal area in particular, has been
widely discussed (Alcamo et al., 2003, Otto et al, 2007). The benefit to the well being of
the population, in terms of health, quality of life and promotion of economic growth are
well known. Yet, while it's easy to assess the economic value of a port, power station and
even residential areas, the value of open space seems to be more elusive. The need for
assessment rose over the years for different reasons such as: the need to decide whether
or not to allow development of a specific coastal area, whether or not to invest in beach
reclamation, the justifiable amount of fine to be charged for violating or harming this
public property. These uses solidified the methods for economic evaluation of the open
unhampered coast line.
Most methods of economic evaluations are based on the extent of beach usage by both
tourists and local residents. Several studies have shown that though beach accessibility,
historic sites, basic services may lend to the beaches attractiveness, Marine litter is the
single most important deterrent to beach usage.
The "Clean Coast Program" has been developed in Israel to combat marine and coastal
litter. This program, now running for 6 years, has served to dramatically increase the
level of beach cleanliness. We would like to argue that through methods of economic
evaluation of the value of the coast line, the regulator can assess the value and annual
budget of such programs.
On the spatial distribution of ocean surface currents
Yosef Ashkenazy1 and Hezi Gildor2
1
Solar Energy and Environmental Physics, BIDR, Ben-Gurion University, Midreshet
Ben-Gurion, Israel
2
The Institute of Earth Sciences, The Hebrew University, Edmond J. Safra campus, Givat
Ram, Jerusalem, 91904
Email: [email protected]
The distribution of ocean currents is important for various applications such as the chance
to encounter extreme events that may affect, for example, marine construction and for
estimating the energy that can be extracted from the ocean. Moreover, for devising better
parameterizations for submesocale mixing, which present climate models cannot resolve,
one should understand the velocity distribution and its relation to the various forcing of
surface ocean circulation. Here we investigate the probability distribution of surface
currents measured by high-frequency radar. Our results show that the distribution of
ocean currents speed can be approximated by a Weibull distribution. Moreover, we
demonstrate the existence of spatial variations of the scale and shape parameters of the
Weibull distribution over a relatively small region of only a few kilometers. We use a
simply surface Ekman layer model to try to understand this spatial variability; it is
apparent that when forced by local winds this model does not reproduce the observations.
We show that Gaussian noise added to the zonal and meridional components of the
bottom geostrophic currents have only a little effect on the surface currents distribution
while noise added to the components of the local wind (mimicking wind gusts) have
much greater effect on the distribution of surface currents, suggesting that wind spatial
and temporal variability underlay the observations.
‫הערכת השינויים מעשי ידי אדם בבריכת נור‪ ,‬במהלך ‪ 60‬השנים האחרונות באמצעות הביוטה הגירית‬
‫אהובה אלמוגי‪-‬לבין‪ ,1‬סטפן מישקה‪ ,2‬רימונה סימן‪-‬טוב‪ ,1‬לידיה פרליס‪-‬גרוסוביץ‪ ,1‬מיכל לייכטר‪ ,3‬מיכה‬
‫‪3‬‬
‫קליין‬
‫‪1‬המכון הגיאולוגי‪ ,‬מלכי ישראל ‪ ,30‬ירושלים ‪; [email protected]@gsi.gov.il; .95501‬‬
‫‪; [email protected] [email protected]‬‬
‫‪2‬אוניברסיטת פריי ואוניברסיטת פוטסדם‪ ,‬ברלין‪ ,‬גרמניה‪[email protected] ,‬‬
‫‪3‬החוג לגיאוגרפיה ולימודי הסביבה ‪,‬אוניברסיטת חיפה‪ ,‬חיפה ‪[email protected]‬‬
‫בריכת נור‪ ,‬הנמצאת בלב רצועת החולות דרומה לנעמן וכ‪ 250 -‬מ' מחוף הים‪ ,‬מייצגת בית גידול יחידאי‬
‫לאורך כל רצועת החולות של חופי ישראל‪ ,‬של גוף מים מליח‪ .‬היא התפרסמה בעבר כבריכת מים מליחים‬
‫שהכילה את התולעת הרב זיפית ‪ Ficopomatus enigmaticus‬וכן את החלזון )‪Ecrobia (Ventrosia‬‬
‫‪ .ventrosa‬במתכונתה הנוכחית הבריכה קיימת כ‪ 60 -‬שנים ובעבר ביח"ר נור‪ ,‬לייצור גפרורים‪ ,‬השתמש בה‬
‫לטבילת בולי עץ‪ .‬לפני למעלה מ‪ 10 -‬שנים חלה ירידה חדה במליחות הבריכה והיא הומתקה‪ .‬כדי לקבוע את‬
‫תכיפות והיקף השינויים שחלו במערכת האקולוגית של הבריכה ובעיקר במליחותה השתמשנו במאספי‬
‫אוסטרקודה‪ ,‬חלזונות ופורמיניפרה שהצטברו בקרקעיתה‪ .‬לצורך המחקר נלקחו בשנת ‪ 2007‬דגימות מים‬
‫וסדימנט מקרקעית הבריכה וכן הוצאו ‪ 4‬גלעינים שאורכם ‪ 20-40‬ס"מ‪ .‬שילוב בין מידע אקולוגי‪/‬סביבתי‬
‫לתצלומי אוויר של אזור הבריכה איפשר לתארך את רצף הסדימנטים שהצטבר בה‪ .‬הערכת השינויים‬
‫במליחות הבריכה התבססו על המידע האקולוגי הקיים לגבי הקבוצות השונות וכן על השימוש בפונקצית‬
‫מעבר שפותחה לאחרונה לגבי קבוצת האוסטרקודה‪ .‬במהלך השנים חלו שינויים ברורים במליחות הבריכה‪.‬‬
‫בתחילת שנות ה‪ 50 -‬של המאה הקודמת הבריכה היתה מליחה עם ‪ .5-5.2 psu‬היא הומתקה קלות בסוף שנות‬
‫ה‪ 60 -‬ל‪ . 4.1-4.4 psu -‬בהמשך‪ ,‬מתחילת שנות ה‪ 70 -‬ועד לשנת ‪ 1994‬היא שבה והיתה מליחה עם ‪5.0‬‬
‫‪ .psu‬החל משנת ‪ 1994‬ועד לאחרונה הבריכה הומתקה ומליחותה נעה בין ‪ .0.8-1.6 psu‬לאחרונה מליחות‬
‫הבריכה שבה ועלתה ובקיץ ‪ 2008‬תכולת המלחים הכללית הגיעה ל‪ 4100 -‬מג"ל‪.‬‬
‫השפעת האדם על בריכת נור נכרת לאורך כל תקופה קיומה‪ .‬כתוצאה מפעילות ביח"ר נור הצטברו בקרקעית‬
‫הבריכה כמויות די ניכרות של עץ וכפיסי עץ שמקורם בבולי העץ הטבולים ולהם היתה כנראה השפעה על‬
‫המערכת הביולוגית והסדימנטרית בבריכה‪ .‬מימדי הבריכה השתנו במהלך התקופה בצורה די קיצונית‪,‬‬
‫בחלקם‪ ,‬כנראה כתגובה לשינויים רב‪-‬שנתיים במערכת ההידרולוגית באזור‪ .‬המתקת הבריכה קשורה ישירות‬
‫להעתקת תעלת ניקוז מי הגשמים של אזור התעשייה עכו‪-‬דרום צפונה‪ ,‬תחילה ישירות דרך הבריכה ובהמשך‪,‬‬
‫בסמוך לבריכה אך עדיין בטווח שמשפיע ישירות על מליחות מימיה‪.‬‬
‫גיאומורפולוגיה וסדימנטולוגיה באזור הקניון התת‪-‬ימי אכזיב‬
‫‪4,3‬‬
‫לנא אשקר‪-‬חלאק‪ 1,2‬רויטל בוקמן‪ 2‬אהובה אלמוגי‪-‬לבין‪ 1‬צבי בן‪-‬אברהם‬
‫‪ 1‬המכון הגיאולוגי לישראל‪ ,‬מלכי ישראל ‪ ,30‬ירושלים‪[email protected]‬‬
‫‪ 2‬החוג למדעים גיאו‪-‬ימיים ע"ש ד"ר משה שטראוס‪ ,‬אוניברסיטת חיפה‪ ,‬הר הכרמל‪ ,‬חיפה ‪,31905‬‬
‫‪[email protected],[email protected]‬‬
‫‪ 3‬בית הספר למדעי הים ע"ש ליון צ'רני‪ ,‬אוניברסיטת חיפה‪ ,‬הר הכרמל‪ ,‬חיפה ‪31905‬‬
‫‪ 4‬החוג לגיאופיזיקה ומדעים פלנטריים‪ ,‬אוניברסיטת תל אביב ‪[email protected]‬‬
‫היווצרות קניונים תת‪-‬ימיים נקשרת לירידת מפלס ים‪ ,‬טקטוניקה וזרמי טורבידיטים והם מהווים נתיב דרכו‬
‫מובלים סדימנטים בפרקי זמן קצרים יחסית ובהיקפי נפח גדולים ממדף היבשת הרדוד לים העמוק‪ .‬הקניון‬
‫התת‪-‬ימי אכזיב מתחתר מול צפון הגליל המערבי והוא הגדול והמפותח מבין סדרה של קניונים המבתרים את‬
‫המדרון הצר מול צפון ישראל‪.‬‬
‫מטרות המחקר הנוכחי כוללות מיפוי מורפולוגי ואנליזה מורפומטרית של קניון אכזיב וסביבתו‪ ,‬הבנת החתך‬
‫הגיאולוגי בו מתחתר הקניון בעזרת חתכים סייסמים רדודים שיבוצעו באזור ודיגום ואנליזה סדימנטולוגית‬
‫של גלעיני סדימנטים ממדף היבשת ומתוך הקניון ודפנותיו בעומקי מים שונים‪ ,‬במטרה ללמוד על אופי‬
‫ההובלה והשקעת הסדימנטים במדף‪ ,‬בתוך הקניון ודרכו אל הים העמוק‪.‬‬
‫עד כה‪ ,‬נדגמו לאורך התוואי של היובל הראשי של הקניון מספר גלעינים (‪ ,)Piston cores‬שאורכם ‪ 2-3‬מ'‬
‫וגלעיני קופסה (‪ )Box cores‬שאורכם כ‪ 50 -‬ס"מ‪ ,‬מעומקי מים של ‪ 40‬מ'‪ 400 ,‬מ' ו‪ 700 -‬מ'‪ .‬כמו כן נדגמו‬
‫מספר גלעינים קצרים (~‪ 30‬ס"מ) בתוך הקניון מעומקי מים ‪ 540-700‬מ'‪ .‬שיקוף רנטגן שבוצע בכל גלעיני‬
‫הסדימנטים אפשר למפות ברזולוציה גבוהה את דפוסי הסדימנטציה בגלעינים‪ .‬זוהו מבני שיכוב מורכבים‬
‫ודפוסי סדימנטציה משתנים‪ .‬בין השאר זוהו בחלק העליון של חלק מהגלעינים למינות דקות שהולכות‬
‫ומתעבות מטה לשכבות שעוביין מספר ס"מ‪ .‬בחלק התחתון של הגלעין הלמינות נעלמות ומופע הסדימנט‬
‫הומוגני‪.‬‬
‫ה‪ ,magnetic susceptibility -‬שהיא דרגת המגנטיות של הסדימנט בתגובה לשדה מגנטי נתון‪ ,‬נבדקה‬
‫לאחרונה‪ .‬בדיקה זו משמשת לזיהוי שינויים בהרכב המינרלוגי של הסדימנט כתוצאה משינויים בתהליכי‬
‫ותנאי ההשקעה‪ ,‬הפאליאו‪-‬אקלים‪ ,‬כיווני זרימה והסעת הסדימנט ומאפשרת לעשות קורלציה בין הגלעינים‬
‫השונים שנדגמו‪ .‬מניתוח ראשוני של התוצאות נראה כי יש התאמה‪ ,‬לפחות ויזואלית‪ ,‬בין אנליזה זו לדפוסי‬
‫השיכוב שזוהו בגלעינים על סמך צילומי הרנטגן‪ .‬הרכב הסדימנט ואופי ההשקעה המשתנה לאורך הגלעינים‬
‫מעיד על דפוסי הסעה והשקעה דינמיים בתוך הקניון ודרכו אל הים העמוק דבר המעיד על שינויים במהלך‬
‫הרביעון באזור הקניון הממוקם בקצה השפעת התא הליטורלי של הנילוס‪.‬‬
Transparent exopolymer particles; microbial shuttles expediting biofilm formation
in desalination facilities
Edo Bar-Zeev1, Ilana Berman-Frank1, Boris Liberman2, Natasha belkin1, and Tom
Berman3
1
Bar Ilan University, Mina & Everard Goodman Faculty of Life Sciences, Ramat Gan,
Israel
2
I.D.E. Kadima, Israel
3
Kinneret Limnological Laboratory, Israel Oceanographic and Limnological Research,
P.O.B. 447, Migdal 14950, Israel
Transparent exopolymer particles (TEP) are ubiquitous in marine and freshwaters, and
have been subject to intensive study by oceanographers and limnologists over the past 15
years. During the last few years TEP has been found to play a role in biofouling
formation though up to date no affective pretreatment procedure (media or membrane)
was found to significantly reduce TEP concentrations. In this study we examined the
claim that TEP are important causative agents in organic fouling and biofilm formation
on membranes in desalination facilities through two pathways. First, along the
pretreatment processes in the Adom desalination plant only decreased TEP feed water
concentrations (50-600 µg GX L-1) by ~30% reaching the RO membranes. Second,
laboratory experiments were carried out to follow the involvement of TEP in the early
stages of biofilm formation. We noticed, using customized flow cells and specific TEP
and bacteria staining that TEP serve as both condition factor for biofilm development and
“microbial shuttles” from the aquatic environment infecting different surfaces in mature
biofilm colonies, accelerating the biofilm forming process.
Taken together, these results imply that TEP in feed waters are indeed likely to be key
players in the establishment and subsequent development of biofilm on membranes. Our
current goal is in developing improved techniques to remove these particles during the
pretreatment procedure in desalination and wastewater treatment plants and by that
reduce biofouling on the RO membranes.
Rapid sand filtration in a newly operated SWRO desalination facility, hints of
biodegradation
Natalia Belkin1, Edo Bar-Zeev1, Boris Liberman2, Tom Berman3 and Ilana BermanFrank1
1
Bar Ilan University, Mina & Everard Goodman Faculty of Life Sciences, Ramat Gan,
52900 [email protected]
2
I.D.E. Kadima, Israel.
3
Kinneret Limnological Laboratory, Israel Oceanographic and Limnological Research,
P.O.B. 447, Migdal 14950.
Rapid sand filtration (RSF) is used today as an efficient and cheap pretreatment
procedure enhancing water quality in desalination plants prior to the reverse osmosis
(RO) membranes. RSF in newly operated desalination facilities requires a "maturation
period" (about three months) before the feed water may be filtered efficiently. Currently,
RSF is considered as a physical barrier only, absorbing different pollutants (>1mm). In
this study, we assessed the role of RSF as a bio-filter by examining the dynamics of
microbial colonization, bacterial metabolic activity, and RSF efficiency during the
“maturation period”. Several parameters of biological organic pollution were examined
weekly in water samples within the RSF layers. These were correlated with bacterial
production and silt density index (SDI). Parallel samples were taken for denaturing
gradient gel electrophoresis (DGGE) and scanning electron microscopy analyses. After
the first 20 operational days up to 90% of chlorophyll a and particulate organic
phosphorous concentrations were removed from the RSF effluent. During the three
months of monitoring, dissolved organic carbon and nitrogen fluctuated greatly reaching
60% removal of feed water concentrations, suggesting that breakdown of particulate
organic matter by bacteria may release dissolved organics. Transparent exopolymer
particles (TEP) were reduced by 30-70%. An increase in bacterial diversity was
confirmed by DGGE analysis while bacterial metabolic activity showed large fluctuations
within the filter bed (20-170%), indicating an unstable bacterial community. Oxygen
consumption by bacteria diminished only ~20% of initial oxygen concentration levels.
We suggest that only 60 days maturation period is required to create a full bio-filtration
profile. Filtration efficiency influenced by bio-degradation will fluctuate in different
seasons of the year.
Does light or photosynthesis enhance calcification in symbiotic corals?
Itay Cohen1,3 Nicola Allison4, Zvy Dubinsky2 Jonathan Erez3
1
Interuniversity Institute of Eilat, P.O.B 469, Eilat 88103, Israel. [email protected]
Faculty of Life Sciences, Bar-Ilan University, Ramat-Gan, 52900, Israel.
[email protected]
3
Institute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem 91904,
Israel. [email protected]
4
Department of Earth Sciences, University of St Andrews, Irvine Building, North Street,
St Andrews, Fife KY16 9AL, UK. [email protected]
2
Light enhance calcification is a crucial factor in coral growth. This phenomena was noticed
already by Vaughan (1919), however the interaction between light and calcification is still
under debate. Photosynthesis and calcification can interact by photosynthetic uptake of CO2
which increases carbonate saturation and favors precipitation of CaCO3 (Goreau, 1959)
leading to enhanced calcification by factor of 3 among corals that carry symbiotic algae
(Gattuso et al. 1999). However, corals’ calcification does not depend directly on
photosynthesis since corals are calcifying also at night (Barnes and chalker 1990). In this
study we measured long term (5 days) influence of inhibitors of photosynthesis (DCMU- 3(3,4-dichlorophenyl)-1,1-dimethylurea) and calcification (Ruthenium red and Verapamil)
on two symbiotic corals, Pocilopora verrucosa and Acropora variabilis. Decoupling
between photosynthesis (measured by Winkler titration) and calcification (change in total
alkalinity) in light and dark conditions confirmed that these processes are interrelated,
however not directly dependent on each other. Both are stimulated by light, even when one
is inhibited. Inhibition of both processes, separately, are strongly dependent on the
concentration and exposure time to all inhibitors used, whereas control corals maintained
with the initial photosynthesis and calcification rates throughout the experiment. Inhibition
of calcification has an immediate negative affect on rates of photosynthesis, whereas
absence of photosynthesis influence rate of calcification only after 24 hours, probably as a
result of deficiency in ATP that may be important to Ca+2 transport or to elevation of pH.
We conclude that light enhance calcification is driven by other light depended processes,
like activation of Ca+2 channels or pumps, but not necessarily by photosynthesis per se.
References:
Barnes D. J. Chalker B. E. (1990) Calcification and photosynthesis in reef-building corals
and algae. Ecosyst World. 25:109-131.
Gattuso J. P. Allemand D. Frankignoulle M. (1999) Photosynthesis and Calcification at
Cellular, Organismal and Community Levels in Coral Reefs: A Review on Interactions
and Control by Carbonate Chemistry. AMER. ZOOL. 39:160-183.
Goreau T. F. (1959) The physiology of skeleton formation in corals. I. A method for
measuring the rate of calcium deposition by corals under different conditions. Biol Bull.
116: 59-75.
Vaughan T. W. (1919) Corals and the formation of coral reefs. Smithsonian Inst., Ann
Rep. 1917: 189-238.
Underwater light field variation in high latitude coral reefs: a case study from the
Gulf of Aqaba.
Gal Dishon1,2, Zvy Dubinsky1, Maoz Fine1,2 and David Iluz1
1
The Mina and Everard faculty of life sciences, Bar Ilan University, Ramat Gan 52900,
Israel.
2
The Interuniversity Institute for marine sciences in Eilat, P.O.B 469, Eilat 88103, Israel
Coral reefs are geographically dispersed at a rather defined belt of ca. 30° south and north
of the equator, with a general trend of decreased biodiversity and growth rate with
latitude increase. One of the northernmost, yet highly diverse, coral reef in the world, is
found in the northern tip of the Gulf of Aqaba (Eilat) at 29° N. Together with its
geographical marginality, this reef is also characterized by low clouds-cover annually,
making it a proper model for demonstrating a "clean" seasonal light field dynamics over
coral reefs in high latitudes.
In this study we describe variations in the underwater light field of Ultra Violet Radiation
(UVR) and Photosynthetically Active Radiation (PAR) along a depth gradient. Our data
show a remarkable seasonal variation in daily irradiance dose that reaches the coral reef.
For example, a coral experiences 7 times less light in the winter compared to summer,
which equals an almost 30m dipper translocation. This seasonal variation in high latitude
coral reefs is derived by a synergetic effect of changes in solar elevation and water
clarity, unlike in low latitude coral reefs, where these differences are very subtle.
Based on this data, we present a model enabling calculation of light filed seasonal
variation as a function of depth and latitude in clear sky conditions.
Red Sea fish in the Mediterranean, as seen through trawl catches in Israel
Dor Edelist
The Leon Recanati Institute for Marine Studies, University of Haifa, Haifa 31905, Israel
The present study describes a rise in Lessepsian ichthyofauna in the Mediterranean in the
last couple of decades via commercial trawl surveys. Time series of trawl samples from
1990-4 and 2000 were compared to current surveys (2008-10). Depth was found to be the
main explanatory factor in describing Migrant distribution and Lessepsian species were
shown to outnumber indigenous fishes on soft bottoms shallower than 83m in current
surveys, while the same trend only applied shallower than 37m in the early 1990's.
Trawling fields in the south of Israel were shown to contain a higher proportion of
migrants than northern fields in all periods. A rise in migrant fishes from 2150 to 7070
individuals/km2 was recorded; vs. a decline in Indigenous fishes from 4900 to 2100
individuals/km2, indicating the same trend. Mean percentages and Shannon's diversity of
migrants in samples have also climbed from 32.8% and 0.75 in 1990-4 to 56.7% and 1.34
today respectively, while these parameters declined for indigenous fishes. Surprisingly,
this trend was reversed in the year 2000 - as they declined to 19.9% and 0.64 respectively
for migrants. The 2000 decline of migrants was only dominant in the autumn and winter
seasons, in which migrants recruit to the fishery. We suggest that the 1998-9 summer trawl
moratoria protected juvenile indigenous ichthyofauna, and may have abetted in 'fighting
off' migrants in those years. A second dataset, of commercial landings from 1949 to 2009,
was extracted from the archives of the Department of Fisheries, and also describes higher
landings of migrants than indigenous fauna in 2009. It can thus be safely said that so far as
soft sediment shallow Ichthyofauna is concerned – the Levantine sea today resembles the
Indo-Pacific realm more than the Atlanto-Mediterranean one.
Mechanisms for surface chlorophyll pattern formation:
satellite based examples from the Eastern Mediterranean
Shai Efrati1, Michael Lazar1, Yoav Lehahn2,3, Eyal Heifetz2
1
Dr. Moses Strauss Department of Marine Geosciences, University of Haifa,
[email protected], [email protected]
2
Department of Geophysics and Planetary Sciences, Tel Aviv University,
[email protected]
3
Department of Environmental Sciences, Weizmann Institute, [email protected]
Satellite images of sea surface chlorophyll (Chl) often reveal a large variety of
spectacular patterns associated with variations in phytoplankton biomass. Despite the
central role of phytoplankton in the global carbon cycle and in the marine food chain, the
relative importance of different biological and physical mechanisms in forming these
surface variability patterns is still under debate.
This work is aimed at providing a detailed, observational-based, understanding of the
mechanisms driving small (~10-100km) scale Chl pattern formation in the oligotrophic
waters of the Eastern Mediterranean. Using satellite observations of Chl, sea surface
temperature and geostrophic surface currents, we classify key mechanisms and separate
the relative contributions of horizontal and vertical motions to the total Chl variance.
Special attention is given to assessing rates and relative contributions of coast to open sea
transport.
Holocene Zevulun Plain wetlands: Evolution and implications
Hadar Elyashiv1 Dorit Sivan2 Revital Bookman1 Dov Zviely3
1
The Department of Marine Geosciences, Leon H. Charney School of Marine Sciences,
University of Haifa, Mount Carmel, Haifa, 31905. [email protected],
[email protected]
2
The Department of Maritime Civilizations, Leon H. Charney School of Marine
Sciences, University of Haifa, Mount Carmel, Haifa, 31905.
[email protected]
3
Recanati Institute for Maritime Studies, University of Haifa, Haifa 31905.
[email protected]
Holocene organic-rich clay units identified in previous studies in coastal sequences along
the Israeli coast, represent wetland conditions. In the current research a high resolution
study is carried out, aiming to reconstruct the evolution and processes responsible for the
organic-rich clay units in Zevulun Plain, the spatial distribution of the wetland
phenomena and their affiliation to human settlement. The organic-rich clay units were
identified in a series of drilling cores along a curved north-south transect in Zevulun
plain, Three cores from the north and south of Zevulun plain were sampled and
characterized combining sedimentological, geochemical and faunal analysis. The
chronology and stratigraphic relationships are based on core logs data collected as part of
the research, as well radiocarbon and luminescence dating.
According to the stratigraphic analysis two distinct wetlands existed in the Zevulun Plain
area during the Holocene. The differences in organic content, the faunal assemblage and
its state of preservation, and the sedimentological composition along the wetland units
point out to different prevailing conditions in the distinct wetlands. Preliminary results
also suggest that the wetland systems were not synchronized in time.
The identified northern wetland area is adjusent to the current Na’aman River whereas
the southern wetland is close to the current Qishon river. These locations imply an
association of the wetlands to different hydrological systems probably during different
periods. In addition, the spatial distribution of the wetlands phenomena and their
affiliation to human settlement is studied in the current research.
The effects of ocean acidification on soft corals from the family Xeniidae
Yasmin Gabay1, Yehuda Benayahu2 and Maoz Fine3
1
Department of Zoology, Tel-Aviv University 69978 [email protected]
2
Department of Zoology, Tel-Aviv University 69978 [email protected]
3
The Interuniversity Institute for Marine Science, Eilat 88013 [email protected]
Approximately 25% of the CO2 emitted from all anthropogenic sources currently enters
the ocean and changes chemical processes. It causes decreasing of carbonate-ion
concentrations which in turn reduces the rate of calcification of marine organisms.
Despite the high abundance of soft corals (Octocorallia: Alcyonacea) on many IndoPacific reefs, up until today the possible effects of declining pH on this group has not
been studied. In the current study it is hypothesized that ocean acidification will affect the
morphology of soft coral sclerites, survival, physiology (i.e., host protein, chlorophyll
zooxanthelae concentration and pulsation rate) and calcification rate of both adult
colonies and primary polyps of soft corals. For this study three species were selected, the
zooxanthellate Ovabunda macrospiculata and Heteroxenia fuscescens (family Xeniidae)
and the azooxanthellate Dendronephthya hemprichi (Nephtheidae). The experimental
design consisted of flow through seawater system which maintained three pH values in
three separate water tables, 7.6 and 7.3 as treatments and 8.2 as a control. The soft corals
were introduced to the system for 30-90 days and tested in several time intervals. The
results indicated no significant differences in all parameters tested between the treatments
and the control. However, when isolated sclerites of O. macrospiculata were introduced
to the system, a considerable variation in the microstructure of the sclerites was found
between the pH treatments and the control as indicated by SEM. The lowest pH treatment
yielded a 9.5 times increase in damaged sclerites compared to the control. It is therefore
suggested that soft corals may not be affected by decrease in pH due to a possible
regulation of the pH within their tissue, while their exposed skeletal elements are
susceptible to such a change. Further research is still needed to examine the vulnerability
of other soft corals to ocean acidification.
Modeling the effect of nutrient loads (N,P) and water levels on water quality
Yael Gilboa1, Eran Friedler1, Arkadi Parparov2 and Gideon Gal2
1
Faculty of Civil and Environmental Engineering, Technion
[email protected], [email protected]
2
Kinneret Limnological Laboratory, Israel Oceanographic & Limnological Research
[email protected] , [email protected]
Water quality (WQ) in lakes and reservoirs is of major concern worldwide. Watershed
affects WQ in the lakes via nutrient loading (N, P) which is dependent on land-use
management. Lake management impacts WQ via water abstraction for supply which
reduces the lake water level (WL). Water abstraction and nutrient loading are therefore
considered as key factors in the management of lakes.
The main objective of this study was to determine the combined effect of nutrient loads
and water levels on WQ in Lake Kinneret through the use of a lake ecosystem model. We
used the hydroecological model DYCD and ran it at WLs ranging between -209 to -218
m under varying nutrient loads, 0.56 to 56.6 gNm-2y-1 and 0.039 to 3.9 gPm-2y-1.
We estimated WQ by using the Composite Water Quality Index (CWQI) and found that
CWQI>60, (minimal quality that allows conservation of the lake ecosystem) could be
maintained only when the lake levels were above -213.4m. For levels ranging between 209 to -213.4m simulation results allowed us to assess the direct relationships between
nutrient loads and CWQI. The graphical solution of these relationships represents a
“polygon” of permissible ranges and critical values of nutrient loads allowing
conservation of the lake WQ at each WL. By calculating the areas of each polygon we
defined a range of WL (-209m to -211.2m) of where CWQI was apparently independent
on the nutrient loads. For a WL < -214, we found that the sensitivity of CWQI to the
loads increases at WLs below -215m.
In this study we demonstrated a new approach for defining acceptable levels of
management measures that will allow sustaining the ecosystem in question. We tested the
approach on the Lake Kinneret ecosystem and succeeded in defining the range of
acceptable management measures through the use of long term simulations of different
scenarios.
The more you observe, the more complex it gets: surface currents observations in
the Gulf of Eilat
Hezi Gildor
The Institute of Earth Sciences, The Hebrew University, Edmond J. Safra campus, Givat
Ram, Jerusalem, 91904. Email: [email protected]
The configuration and dimensions (nearly rectangular, 10 km x 6 km) of the northern gulf
of of Eilat enable the observation of surface currents at unprecedented high spatial and
temporal resolution using high-frequency (HF) radar. For more than five years, a pair of
HF 42MHz SeaSonde stations provides two-dimensional maps of surface currents every
30 min with a spatial resolution of about 300 m. These observations fill existing
observational gap between fine-structure turbulence (millimeters to meters) and studies of
the mesoscale (10s-100s km).
Our observations yielded important, unexpected results, including: The identification of
temporary barriers to mixing that last for few days; Occasional and perplexing presence
of a large (much of the domain) spatially coherent eddy with a lifetime of a day or so;
The existence of long-range temporal correlations, from a timescale of several hours to a
timescale of several months, in the Eulerian currents.
These findings have important implications for the dispersion of pollutants, nutrients,
larvae, etc., and therefore for a wide range of predictions. They also suggest that a new
approach to the way mixing is parameterized in ocean and climate models is required.
‫הפרשות דגים באילת ‪ -‬ממטרד סביבתי למנוף כלכלי‬
‫אשר גתי ‪ -‬יועץ סביבתי*‪ ,‬מושב מגדים ‪[email protected] 30875 ,74‬‬
‫לפני כשנתיים וחצי הוצאו כלובי הדגים ממי מפרץ אילת‪ .‬עד להוצאתם מהמפרץ סיפקו חוות הדגים באילת‬
‫את כל תצרוכת מדינת ישראל בדגי יוקרה ואף ייצאו מדי שנה כ‪ 10-‬טון דגי דניס משובחים לירדן ולמצרים‪.‬‬
‫היצור השנתי של החוות עמד על כ‪ 3500-‬טון דגים ‪ -‬בעיקר‪ ,‬דניס ולברק‪ .‬מאחר והוצאת הכלובים לא‬
‫שפרה כמצופה את שמורת האלמוגים‪ ,‬מומלץ להחזיר את חוות הכלובים למפרץ תוך נטרול מוחלט של‬
‫השפעתם הסביבתית כמתואר להלן‪:‬‬
‫מכלובי הדגים באילת‪ ,‬בנפח ‪ 250,000‬מ"ק‪ ,‬נפלטה‪ ,‬בזמנו‪ ,‬לשלשת המעורבת בעודפי מזון וכן ‪ 240‬ט' חנקן‬
‫ו‪ 40-‬ט' זרחן (לשנה)‪ .‬אלה גורמים להתפתחות אצות‪ ,‬הפוגעות בשמורת האלמוגים ומזהמות את חופי‬
‫הרחצה התיירותיים המהווים את בסיסה הכלכלי של העיר‪ .‬אולם‪ ,‬אפשר למנוע את השפעת הכלובים על‬
‫הסביבה הימית ‪ -‬ועוד להפיק מכך תועלת כלכלית‪:‬‬
‫‪ .1‬אזור הכלובים יופרד ממי המפרץ באמצאות "חיתול" פלסטי‪ ,‬אשר קצהו התחתון מחובר לצינור יניקה‪,‬‬
‫המנקז את תכולתו לבריכת שיקוע הנמצאת על החוף (ר' תרשים)‪ .‬למניעת סתימת הצינור בצמדת‪-‬ים‪ ,‬מי‬
‫מפרץ ‪ -‬המוזרמים לחיתול באמצעות "אל‪-‬חוזר" ‪ -‬עוברים תחילה דרך "מסנן ביולוגי"‪ .‬ע"י שינויים‬
‫בחיתול‪ ,‬ניתן להורידו אל מתחת לפני המים (לעומק ‪ 10-25‬מ')‪ .‬בכך תתאפשר הגנה על הכלובים‬
‫בסערות ושליטה על תהליכי הרבייה‪ .‬מאחר וקיים יחס ישר בין קצב החלפת המים לבין הפרודוקטיביות‬
‫של הכלובים‪ ,‬הרווחיות של הענף תהייה פונקציה של ניהול יעיל ‪ -‬ולא על חשבון האינטרס הסביבתי‪.‬‬
‫‪ .2‬המים המועשרים בדשנים יועברו מבריכת השיקוע לסדרת בריכות אשר ישמשו לגידול מסחרי של אצות‬
‫מאכל ‪ -‬המבוקשות מאד בשווקי אסיה המזרחית ‪ -‬ולאחר מיצוי הדשנים‪ ,‬יועברו המים הנותרים לשימוש‬
‫בתעשיית המלח‪ .‬הרחבת הענף תוכל לשמש מנוף לפיתוח יישובי הערבה הדרומית‪.‬‬
‫‪.3‬‬
‫החומר האורגאני שיוצא מתשתית בריכת השיקוע‪ ,‬יועבר לפארק תיירותי שיאוכלס בעופות מים‬
‫אקזוטיים (פלמינגו) ולאחר ייבושו ישמש להזנת בהמות ‪ -‬באמצעות אבני ליקוק מינרלים‪.‬‬
‫ראוי ליישם (בהדרגה ובאמצעות "מתקן חלוץ") את טכנולוגית החיתול המתוארת לעיל‪ .‬טכנולוגיה זו‪ ,‬בצרוף‬
‫המסנן הביולוגי (שבמקורו נועד לשמור על ניקיונם של מערכות מי‪-‬הקירור בתחנות‪-‬כוח)‪ ,‬נרשמה כבקשת‬
‫פטנט‪.‬‬
Seasonal variability in fractionation of sulfur isotopes in a freshwater marsh – Hula
nature reserve
Golan R. 1,2, Gavrieli I. 2, Merkel D. 3 Lazar B. 1
1
Institute of Earth Sciences, the Hebrew University, Jerusalem 91904, Israel
Geological Survey of Israel, Jerusalem 95501, Israel
3
Lake Kinneret & Watershed Monitoring & Management, Water Authority, Israel
2
Hula nature reserve was established to preserve the unique faunal and floral population
that occupied the historic Hula Lake and marshes before their drainage in the 1950s.
Since its establishment the proportion of poor quality water (fish ponds and sewage
effluents) that fed the reserve increased with time. However, starting in 2005 and
following a reconstruction project high quality Jordan River water became the main water
source for the reserve. This study describes the major biogeochemical processes in the
reserve after the rehabilitation, and focuses on the sulfate system. The main finding was
that the reserve is an effective sink to SO42- due to intense bacterial sulfate reduction
(BSR). Sulfur isotopic analyses show that the isotopic fractionation factor during the
BSR has a seasonal variation, indicating that the process is also seasonally dependant.
Water samples for major and trace elements analyses were collected monthly from the
main water bodies of the reserve during 11/2006-1/2008. Seasonal isotopic data were
collected (three winter and three summer months). The anion Cl- was used as the
conservative parameter for assessing SO42- depletion/enrichment.
The SO4/Cl ratio in the “Lake” (the main pond of the reserve) indicates that ~30% of the
SO42- entering the reserve was depleted during winter and ~80% during summer. During
winter δ34SSO4 of the inflow was ~4.3‰ while the outflow was ~17.8‰, representing
BSR fractionation factor of 41‰. During summer however, no significant shift in δ34SSO4
was observed between the inflow and the outflow despite the significant depletion of
SO42-. Apparently, seasonal variations in temperature and substrate availability controlled
the SO42- demand over the year. It appears that following the intensive BSR during the
summer, SO4 availability became the limiting factor for the process. In the “Saduk” (a
side pond) BSR was accompanied by winter gypsum dissolution. This gypsum is derived
from oxidation of sulfide from the newly exposed Hula Lake sediment.
Marine Sedimentological Signatures from the 2010 Winterstorm Event in Caesarea
Beverly Goodman1 and Jacob Sharvit2
1
University of Haifa, Leon Charney School of Marine Sciences, Strauss Department of
Marine Geosciences
2
Department of Antiquities, Marine Antiquities Unit
Evidence of erosion along the Caesarea coastline is apparent for both recent and ancient
periods. While regular, gradual erosive coastal energy is responsible for a portion of the
change along the coastline, rarer high energy events, such as tsunamis and major storms,
also contribute to this process. In mid-December 2010 a large storm impacted the Israeli
coastline with measured wave heights of 13.7 meters in Haifa. The impact of the storm
on the coastline was significant, transporting large sections of concrete from a modern
wave breaker, scouring the base of the ancient aquaduct, and scraping 1-2 meters off of
the face of coastal cliffs. A partial transect (30-0m) of sediments was collected prior to
the storm. The sediment samples were characterized with regard to sorting,
granulometry, and character. A comparison of sediments from modern non-storm, storm,
ancient non-storm, ancient storm, and ancient tsunami will be presented.
Stable C and N isotopes in Lake Kinneret food web: past and present
Aram Goodwin1, Jonathan Erez1 and Tamar Zohary2
1
The Institute of Earth Sciences, the Hebrew University of Jerusalem, 91904, Israel
[email protected], [email protected]
2
Kinneret Limnological Laboratory, Israel Oceanographic and Limnological Research
P.O.B. 447, Migdal, 14950, Israel [email protected]
Changes relating to the food web of Lake Kinneret have been documented in the past two
decades. The causes and effects of which are not well understood. In this study stable C
and N isotopes (noted as δ13C and δ15N) have been determined in samples of particulate
organic matter (POM), CaCO3, zooplankton, fish and littoral invertebrates collected from
the lake on a monthly basis. The results were analyzed and compared to a former δ13C
record of the same components from two decades ago in order to gain further ecological
insights concerning the lake. At the base of the food web POM and zooplankton
presented lower summer δ13C peaks than past ones by 4 ‰ and more. This was linked to
the documented changes in the phytoplankton community and implied additional changes
in the annual production cycle in the lake. Further up the food web the average δ13C of
fish Sarotherodon galilaeus was found 2.4 ‰ lower than in the past but 2.5 ‰ higher
than the biomass weighted annual mean δ13C-POM suggesting selective feeding on a yet
undetermined component. POM from surface water, from sediment traps and
zooplankton were strikingly more similar to one another in their annual δ15N than in their
annual δ13C suggesting that N isotopes are more homogenously distributed than C
isotopes in the different constituents which comprise the bulk POM. It follows that the
striking resemblance between POM and zooplankton in their annual δ15N signifies a
complete recycling of zooplankton’s biomass in a matter of days. Overall 15N enrichment
between all known trophic levels in the lake has been presented clearly and the
independently documented food chain: POM → zooplankton → Acanthobrama
terraesanctae (Kinneret “sardine”) → Carsobarbus canis presented an average trophic
enrichment factor of 2.9 ‰.
Differential morphological features of two Dendronephthya soft coral species suggest
differences in feeding niches
Michal Grossowicz and Yehuda Benayahu
Department of Zoology, Tel Aviv University, George S. Wise Faculty of Life Sciences,
Ramat Aviv, Tel Aviv 69978, Israel
Octocorals are characterized by pinnate tentacles and internal sclerites. Their feeding
ability is determined by the morphological features of the polyps. Capture of food
ingested by these corals is also affected by the flexibility of the colony, which in turn is
determined by the features of the sclerites. We studied the morphological features of two
azooxanthellate octocorals, Dendronephthya hemprichi and D. sinaiensis, whose depth
distribution partially overlaps along the pillars supporting Eilat’s oil jetty (northern Red
Sea). Following Gause’s hypothesis, such coexistence is possible if each species is
adapted to utilize different food items. In order to examine this hypothesis, the features of
the polyps of the two species and their sclerites were examined. Each side of their
tentacles features 11-13 pinnules, which are longer at the tentacle's distal end compared
to its median and proximal ones, with the distal pinnules of D. sinaiensis being
significantly longer than those of D. hemprichi. At the proximal end of the tentacles of D.
sinaiensis, adjacent to the mouth opening, the pinnules emerge perpendicularly, unlike in
D. hemprichi, where they emerge from the lateral sides; the distance between the rows of
pinnules is, therefore, significantly smaller for the former. These findings imply that the
filtered phytoplankton ingested by the two species may differ in size. The sclerites of the
two species also differ in size and shape and therefore the expansion and contraction
abilities of their polyps also differ, and may thus affect their respective feeding abilities.
The results indicate that D. hemprichi and D. sinaiensis utilize different food items, and
therefore support Gause’s hypothesis and explain the coexistence of the two species.
In the footsteps of Connell: Using molecular tools for resolving patterns of zonation
Tamar Guy-Haim1,2, Gil Rilov2, Yair Achituv1
1
The Mina & Everard Goodman Faculty of Life Science, Bar-Ilan University, RamatGan 52900, Israel. [email protected]
2
Israel Oceanographic and Limnological Research, National Institute of Oceanography,
P.O. Box 8030, Haifa 31080, Israel.
Three eminent breakthroughs in the history of biology owe their discovery to cirripede
(barnacles) exploration: Thompson’s work on cirripede life-cycle contributed to
understanding larval biology, Darwin’s taxonomic research influenced the writing of The
Origin of Species, and last but not least – Connell’s demonstration of the interspecific
competition mechanism between two rocky intertidal cirripede species. Connell’s study,
conducted fifty years ago, is considered a pioneering work in the field of ecology, since it
used controlled experimental manipulations of populations in a natural field situation. As
a result of his study, the prevailing theory regarding intertidal species zonation is that the
lower limit of distribution is mainly determined by biotic factors such as competition or
predation, while the upper limit is set by physical factors.
The objective of this study is to test the generality of this model using two common
intertidal Mediterranean cirripede species: Chthamalus stellatus dominates the lower
zone, and Euraphia depressa, occupies the uppermost intertidal zone, but is also common
on lower cryptic surfaces. The following questions have been studied: Is settlement
habitat specific or random? At what point in the recruitment process is zonation created?
and by which factors? For many years, these questions remained unanswered, since the
last larval stage (cyprid) and young metamorphs (spats) lack any recognizable
morphological features that discriminate between the species.
Following Connell’s experimental methods, the dispersal patterns of adult populations
were studied at four sites: Akhziv, Shikmona, Habonim and Palmachim. Settlement and
recruitment were assessed using standardized double-sided settlement plates, at sampling
intervals of a day, a week and one month, during Aug 2009 – Dec 2010. Reciprocal
transplantation experiments of settlers between zones and settler exposure were held. The
settling individuals were counted, measured and identified to species using molecular
analysis, using a discriminating system we developed, based on PCR of 16S mt rDNA
gene with species-specific primers.
Results show that spats of C. stellatus are found on the front side of the plates, whereas
spats of E. depressa are found on the back side, mainly within the lower belt, close to the
waterline. No significant difference in species ratio was found between small and large
sampling intervals, suggesting that settlement site is determined at the earliest stages.
Shifting C. stellatus individuals to the high belt resulted in a high mortality rate, while
exposing E. depressa individuals that settled in cryptic niches in the low belt had no
effect on their survival (i.e., they were not overgrown by C. stellatus although E.
depressa at the younger stages are much more fragile than the C. stellatus). This
surprising finding rejects the hypothesis, based on Connell’s idea, that E. depressa lower
limit is controlled by competition with C. stellatus. We suggest that during the early
period of life, young E. depressa individuals are more susceptible to wave action than C.
stellatus individuals, resulting in the observed zonation pattern.
Quaternary sequences of fringing reef development along the northern shelf of the
Gulf of Eilat/Aqaba
Gal Hartman1,2, Zvi Ben-Avraham1,3, Gideon Tibor2,3, Tina M. Niemi4, Abdallah AlZoubi5, Ronnie A. Sade3, John K. Hall6 , Emad Akawi5, Abdelrahman Abueladas5, Rami
Al-Ruzouq5and Yizhaq Makovsky3
1
Department of Geophysics & Planetary Sciences, Tel-Aviv University, Tel-Aviv, Israel.
[email protected], [email protected]
2
Israel Oceanographic and Limnological Research, Haifa, Israel. [email protected]
3
Dr. Moses Strauss Department of Marine Geosciences, Charney School of Marine
Sciences, University of Haifa, Haifa, Israel. [email protected] ,
[email protected]
4
Department of Geosciences, University of Missouri-Kansas City, Missouri, U.S.A.
[email protected]
5
Surveying & Geomatics Department, Al-Balqa' Applied University, Al Salt, Jordan.
[email protected]
6
Geological Survey of Israel, Jerusalem, Israel. [email protected]
Quaternary reefs generation and demise have been shown to relate worldwide with, and
provide markers of, sea level fluctuations and related environmental changes. Yet, the
mechanisms and rates affecting this relation are not well resolved. In this paper we show
a correlation between cycles of fringing reef growth and mortality, changes in sea level,
and the style of sedimentary deposition along the northern shelf of the Gulf of
Eilat/Aqaba (GEA). The later presumably relate with local climatic changes. We
interpreted a set of high resolution seismic reflection and multibeam bathymetric data and
defined six systems of relict fringing reefs. The two uppermost relict fringing reefs are
also exposed on the seafloor at water depths of ~20 m and ~65 m, along the northwestern
corner of the northern GEA and sub-parallel to the current northern coast respectively.
The upper three reefs systems are embedded within the two upper stratigraphic
sequences, presumably representing the last two transgressive system tracks. These reefs
and the units in which they are embedded portray a repeating stratigraphic pattern of reef
development during deposition of homogenous sediment and a following demise during
deposition of heterogeneous sediment. We interpreted two relict fringing reefs embedded
within each of the last two transgressive system tracks, implying that each of the last two
sea level rises included two slow-downs of sea rise during exceptionally arid periods.
Correlation of our results with previously published late Quaternary rates of sea level
rise, climatic events, and reef generation phases leads to an age model of the interpreted
events. We suggest two phases of fringing reef generation during the last deglaciation
(since ~19ka BP); the older reef developed between 12.9-11.7 ka BP at ~60 m below sealevel and the younger reef developed between 8.4-8 ka BP at ~20 m below sea-level.
These last two events of reef generation are separated by a period of intensive input of
terrestrial sediment, accumulated during high flow regime, presumably related with an
exceptionally humid period. We suggest that fringing reefs evolved along the northern
shelf of the GEA only during relative slow-downs in sea level rise combined with low
input of terrestrial sediment, suggesting the predominance of exceptionally arid climate.
At present, no fringing reef grows along the northern coast of the GEA, suggesting that
these exceptionally arid periods were more arid than Recent. The pattern of sea level rise
slow-down simultaneously with exceptionally arid conditions seems to have repeated
during the last two sea level rise cycles, suggesting a common mechanism of short
(~1000 years) phases of climatic cooling during deglaciations.
‫שיטות סטטיסטיות לבחינת השפעת פחם נושר לקרקעית מזח הפחם בחדרה על הופעת הבנתוס‬
‫‪3‬‬
‫לין היאמס‪ ,1‬אורית ברנע‪ 2‬וענת גלזר‬
‫‪1‬המחלקה לסטטיסטיקה וחקר שווקים‪ ,‬חברת חשמל‬
‫‪2‬בית הספר למדעי הים המרכז האקדמי רופין‬
‫‪3‬מעבדה ימית‪ ,‬חברת חשמל‬
‫במהלך פריקת הפחם במזח הימי שבחזית תחנת הכח אורות רבין בחדרה‪ ,‬נושר אחוז מזערי ממנו לקרקעית‪.‬‬
‫במסגרת תוכניות הניטור הסביבתי ימי שחברת החשמל נדרשת לבצע על ידי המשרד להגנת הסביבה‪ ,‬נבדק‬
‫בין היתר פיזור הפחם הנושר על הקרקעית והשפעתו על הבנתוס‪ .‬בניטור האחרון שבוצע ( בשנת ‪)2009‬‬
‫מוינו וסווגו ‪ 32,125‬פרטי מיובנתוס המאכלסים את הקרקעית החולית‪ .‬הנציגות הגבוהה ביותר הייתה‬
‫ל‪ Nematoda -‬אשר כללה ‪ 57%‬מכלל הפרטים‪ .‬נוכחות התולעים הרב זיפיות (‪ – (Polychaeta‬עמדה על‬
‫‪ .16%‬נציגים מה ‪ Crustacea -‬היוו ‪ 12%‬ומתוכם הנוכחות הגבוהה ביותר הייתה לסדרות ‪,Tanaidacea‬‬
‫‪ Amphipoda‬ול‪. Copepoda -‬‬
‫בחינת השפעת הפחם הנושר על הופעת הבנתוס בוצעה בעזרת שיטות סטטיסטיות רב‪-‬מימדיות מלוות‬
‫במבחנים סטטיסטים‪ .‬לשם כך‪ ,‬מיון הבנתוס קובץ לקבוצות עיקריות‪:‬‬
‫‪.Phoronida, Echinodermata, Polychaeta, Crustacea, Mollusca, Nematoda‬‬
‫שיטות סטטיסטיות רב –משתניות מסוג ‪, PCA- Principal Component Analysis‬‬
‫‪ NMDS-Non-Metric Multidimensional Scaling‬הופעלו לבחינת השוני בין נקודות הדיגום והשיטה‬
‫‪ RDA -Redundancy Analysis‬לבחינת הקשר בין המשתנים הביוטיים למשתנים‬
‫הא‪-‬ביוטיים (עומק‬
‫ואחוז משקלי של פחם)‪.‬‬
‫מהניתוחים נמצא כי קיים קשר מובהק בין הופעת החי לעומק המים וכי לא קיים קשר בין הופעת החי לאחוז‬
‫המשקלי של הפחם בחול‪ .‬כאופייני לתפוצת החי בתוך המצע ברוב נקודות הדיגום העמוקות‪ ,‬מספר‬
‫הפרטים גבוה יותר‪ .‬הניתוחים הסטטיסטיים הראו כי אין הבדל מובהק בהופעת החי בתוך המצע בין שנת‬
‫‪ 2009‬לשנת הניטור הקודמת‪ ,‬שנת ‪.2004‬‬
Pollution effects on the benthic intertidal algal flora along the Israeli Mediterranean
shores
Razy Hoffman1, Alvaro Israel2, Zvy Dubinsky1 and David Iluz1
1
The Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat
Gan 52900, Israel
2
National Institute of Oceanography, Israel Oceanographic and Limnological Research,
P.O. Box 8030, Haifa 31080, Israel
A comprehensive four-year algal survey that took place at 12 abrasion platform sites
along the Israeli Mediterranean coast compares the marine flora at 5 polluted (high heavy
metal and nutrient levels) locations to that growing at 7 unpolluted sites. This survey also
documents the recent marine flora on the Israeli Mediterranean intertidal and provides an
updated algal checklist published for that area. A total of 152 algae taxa were found: 11
Cyanobacteria, 43 Chlorophytes, 68 Rhodophytes, and 30 Heterokontophytes. Total taxa
numbers at all polluted sites were remarkably lower compared to the unpolluted ones.
More Cyanophyte taxa were found in polluted sites while higher numbers of
Chlorophyta, Rhodophyta, and especially Heterokontophyta were found in clean
localities. Several new Indo-Pacific alien seaweed species were also reported for the first
time.
Supported by NATO SfP 981883 Grant
The effect of the Nile and the Shafdan outlet on benthic fauna of the Israeli shelf:
foraminifera and mollusca assemblages
Orit Hyams-Kaphzan1, Yael Edelman-Furstenberg1, Barak Herut2, Chaim Benjamini3 and
Ahuva Almogi-Labin1
1
Geological Survey of Israel, Jerusalem 95501 [email protected]; [email protected];
[email protected]
2
Israel Oceanographic & Limnological Research, National Institute of Oceanography,
Haifa 31080 [email protected]
3
Chaim Benjamini, Department of Geology and Environmental Sciences, Ben Gurion
University of the Negev, Beer Sheva 84105 [email protected]
Recent man-induced changes (the Shafdan sewage outlet) in the Israeli Mediterranean
shore have had a strong ecological imprint on the biota, in the otherwise oligotrophic
eastern Mediterranean. This study aims to compare the effect of the natural 'nilotic'
province and the anthropogenic Shafdan area with regards to living benthic foraminifera
and death-assemblage record of mollusca. Those two groups are known to be sensitive
indicators of seafloor conditions.
An along-shore transect that crosses the treated sewage sludge area (Shafdan, PL3) but
also includes areas peripheral to the main impact area (north of the Shafdan, PL29 and
Ashqelon, AS1) were sampled bi-monthly between 2003 and 2004 from water depths of
33-38 meters.
Live benthic foraminifera and dead molluscan assemblages were examined for their
community structure and taxonomy.
PL29 is characterized by high abundance and diversity values showing large seasonal
variation (high during summer, low during winter) and deep average living depth (ALD).
PL3 and AS1 are characterized by low to moderate abundance and diversity values, small
or different seasonal pattern and shallow ALD. However, the assemblages at both the
Shafdan sites represent a common pool of species, with Ammonia tepida highly
dominant. At Ashqelon different species are dominant.
Eighty molluscan species were identified. Molluscan results from PL3 show that species
richness and number of specimens/gram sediment are significantly lower than those from
the peripheral stations. Unexpectedly, there is a considerable difference in these
parameters between summer and winter death assemblages from the treated sewage outlet
station. This may point to an extremely strong impact of the sewage on the fauna for this
station.
The differences seen in the micro- and macrobenthic assemblages can be attributed to the
decreasing affect of the Nile northwards and local affect of the Shafdan outlet on the
Palmachim area on the benthic environment.
Sediment reworking events in submarine cores from the Northern Gulf of AqabaEilat
Mor Kanari1, Zvi Ben-Avraham1, Abdallah Al-Zoubi2, Gideon Tibor3, Tina M. Niemi4,
Revital Bookman5, Beverly N. Goodman Tchernov5, Gal Hartman1, Abdel-rahmen
Abueladas2, Rami Al-Ruzouq2, Emad Akawi2 and Shmulik Marco1
1
Dept. of Geophysics & Planetary Sciences, Tel-Aviv University, Tel-Aviv, Israel, *
[email protected]
2
Surveying & Geomatics Dept., Al-Balqa' Applied University, Al Salt, Jordan
3
Israel Oceanographic and Limnological Research, Haifa, Israel
4
Dept. of Geosciences, University of Missouri-Kansas City, U.S.A.
5
Dept. of Marine Geosciences, School of Marine Sciences, University of Haifa, Israel
We aim to identify and date sediment reworking events in submarine cores, e.g.
slumping, turbidites or tsunami/seiche deposits, and determine if they were tectonically
induced. We analyze cores extracted across the Northern Gulf of Aqaba-Eilat (NGAE),
located at the southern part of the Dead Sea Transform and subjected to its tectonic
activity: based on seismic and bathymetric analyses, prior studies suggest that the
offshore Evrona and West Aqaba faults situated within the gulf are recently active.
The study addresses the following questions: (a) What is the Holocene earthquake record
of the NGAE (i.e. long and short term recurrence intervals, magnitudes)? (b) How and
where can we identify tectonically induced sediment reworking events in cores (e.g.
tsunami, seiche, turbidity flows)? (c) How can we correlate reworking deposits in the
sedimentary column across the Gulf to specific climatic / tectonic events?
We have recovered 27 piston cores, 6 vibrocores and 3 diver-assisted air-hammer cores
from across the NGAE at varying water depths of 20-550 m, with variable sediment
recovery lengths (50-450 cm). Determination of coring sites was based on high-resolution
seismic survey and morphological analysis of multibeam bathymetry, seeking for
potential earthquake-induced features (e.g. slump scarps, active faults, submarine
canyons).
Grain size distribution is used to identify depositional sequences typical of sediment
reworking events. Radiocarbon dating of the core sequences will reveal the timing of
earthquake-induced sedimentary events and will establish the Holocene seismic record of
the NGAE region. Age determination of offset features identified in seismic data may
help to suggest slip rate for the Evrona Fault. Magnetic susceptibility core profiles are
used to inter-correlate cores from different locations across the NGAE.
Acknowledgements
This study is conducted as part of a joint research team of Jordanian, Israeli and US
scientists, funded by the Middle East Regional Cooperation (MERC) program grant TAMOU-08-M29-036.
Mesoscale variability of shallow water medium and acoustical monitoring of these
perturbations
Boris Katsnelson
University of Haifa, Mount Carmel Haifa, 31905. Israel, [email protected]
Spatial and temporal variability of the shallow water medium (coastal area or shelf zone
of the ocean) is one of the most remarkable features of the ocean. In given talk author
deals with the “mesoscale” perturbations, having spatial scales about from a few
hundreds of meters to a few kilometers, and temporal scales from a few minutes to a few
hours. These perturbations are internal waves (especially nonlinear ones), currents,
temperature fronts, moving inclusions of different nature, topographic variations
(underwater mountains, canyons) etc. Remark that spatial variability has different scales
in vertical and horizontal planes (a few tens and more than a few hundreds of m
correspondingly), and there is some anisotropy in the horizontal plane as well. Some
examples of non-stationary behavior of the water layer due to tides and nonlinear internal
waves obtained in experiments are demonstrated. Author considers low frequency sound
waves propagation through varying medium as the base for acoustical monitoring of
mesoscale perturbations in a large scale area (about 50x50 km). Ray trajectories, intensity
variations and interference pattern in horizontal plane are analyzed as the main set of data
to get connection of parameters of the acoustical signal with parameters of perturbations
(velocity, position etc.). Theoretical techniques for description of the sound field in the
variable shallow water media as well as experimental examples are presented. It is shown
that for nonlinear internal waves it is possible to estimate some parameters using
acoustical data within the framework of simple model.
Sphingolipids in phytoplankton bloom termination: from gene prediction to cellular
mechanism and detection of viral infection in the ocean
Ruth Khait1, Shilo Rosenvasser1 , Shifra Ben-Dor2, Elad Lavee Laviad3 , Ilana Rogachev1
and Assaf Vardi1
1
Department of Plant Sciences
Bioinformatics and Biological Computing Unit, Biological Services, 3Department of
Biological Chemistry, Weizmann Institute of Science
*Corresponding author: [email protected]
2
Emiliania huxleyi is a cosmopolitan coccolithophore that frequently forms massive
oceanic blooms, which play a major role in global carbon and sulfur cycles. Nevertheless,
the molecular signaling mechanisms controlling both bloom formation and termination
are yet to be determined. Emiliania huxleyi virus (EhV) is assumed to be a major cause
for E. huxleyi’s sudden bloom termination. EhV's genome has unexpectedly indicated the
presence of the de-novo sphingolipid metabolic pathway, never seen before in any other
viral genome. Sphingolipids are known to play crucial roles in cell signaling,
proliferation, apoptosis and in host-virus interactions. We have recently shown that
sphingolipids play important role in EhV infection and induction of E. huxleyi apoptosis
during lytic phase.
Currently, we aim to expand our knowledge regarding their role in mechanisms of host
resistance to viral infection and viral replication cycle. We take the following approaches:
1) in depth in silico examination of sphingolipid related genes both in the virus and in the
host genomes and transcriptomes 2) gene expression analysis of sphingolipid related
genes during the course of viral infection 3) protein expression and function analysis by
enzymatic activity assays and specific antibodies 4) analysis of sphingolipid during the
course of viral infection using mass-spectrometry and metabolic labeling. Our
preliminary results show that key genes in sphingolipid pathway induced by several
orders of magnitude during the course of viral infection. Mass-spectrometry analysis
showed large accumulation of ceramide, a key sphingolipid, during lytic viral infection.
Furthermore, several sphingolipid biosynthesis enzymatic activities showed large
differences in basal activity levels between sensitive and resistant host strains to EhV. In
addition inhibitors of these enzymes modified the level of host susceptibility to viral
infection. Future identification of these unique viral-derived lipids may be utilized for
development of novel biomarkers to detect viral infections in the ocean.
Vertical mixing induced by wind and a rotating screen in a stratified fluid in a
channel
E.Kit, E.Berent and M.Vajda
Technion Israel Institute of Technology, Haifa, Israel.
An experimental investigation of vertical mixing induced by wind , or by a screen which
moved horizontally over the water surface, was carried out in a wind-wave channel
similar to that of Wu (27). It was found that, in a wind-wave channel, the entrainment
rate due to the shear stress, which was exerted on the water surface by the moving screen,
was two orders of magnitude smaller than the one obtained in a similar experiment,
which were carried out in an annular tank by Kao&Phillips (11), Kantha et al (10).
The entrainment rate in the wind induced mixing experiment, was one order of magnitude
larger than that found in the experiment with the horizontally moving screen, both carried
out in the same channel.
The explanation of these differences, which is offered in this work, is based on the
analysis of the flow pattern in the mixed layer in both systems.
An additional important result, is the fact that, the relation between the entrainment rate,
E, and the Richardson number, Ri, agrees with the one obtained by Turner (21), and other
authors, i.e. E Ri-³/² , particularly in the experiments of wind induced mixing.
‫פאונת הטפילים במיני דגים פולשים ומקומיים במזרח הים התיכון‪ ,‬הנתון תחת השפעת השינוי האקלימי‬
‫‪3‬‬
‫יעל קלופמן‪ 1‬אריאל דיאמנט‪ 2‬מנחם גורן‬
‫‪ 1‬ביה"ס ללימודי סביבה ע"ש פורטר‪ ,‬אוניברסיטת תל אביב‪[email protected] ,‬‬
‫‪2‬המרכז הלאומי לחקלאות ימית‪ ,‬חקר ימים ואגמים לישראל‪[email protected],‬‬
‫‪3‬המחלקה לזואולוגיה‪ ,‬אוניברסיטת תל אביב‪[email protected],‬‬
‫פלישתם המסיבית של מינים טרופיים ים סופיים דרך תעלת סואץ היא אחד הגורמים המשמעותיים המשפיעים‬
‫ביותר על מזרח הים התיכון בעשורים האחרונים‪ .‬למרות המחקרים הרבים שנערכו בנושא‪ ,‬עדיין קיים ידע‬
‫מועט יחסית על תפקיד הטפילים בזירה זו‪ .‬בנסיון להסביר את ההצלחה יוצאת הדופן של מינים פולשים‬
‫מסויימים‪ ,‬שיצרו אוכלוסיות גדולות והתפרסו פני שטחים נרחבים‪ ,‬בעוד הצלחתם של אחרים נראית מוגבלת‬
‫ושולית‪ ,‬הוצעה תאוריית ה"שיחרור מאוייבים" ("‪ )"Enemy Release Hypothesis‬כהסבר אפשרי‬
‫לתופעה‪ .‬במחקר הנוכחי‪ ,‬בדקנו את שכיחותם ותפוצתם של טפילים רב תאיים ב‪ 20-‬מיני דגים פולשים‬
‫("מהגרים לספסיאניים") ומקומיים לאורך חופי הלבנט (ישראל וטורקיה)‪ .‬בסך הכל‪ ,‬נבדקו ‪ 648‬דגים‬
‫לנוכחות אקטופרזיטים (טפילי זימים‪ ,‬עור‪ ,‬פה‪ ,‬עיניים) ואנדופרזיטים (טפילי מערכת העיכול)‪.‬‬
‫הנפיצות של כל קבוצות הטפילים שנמצאו במינים המקומיים בים התיכון הייתה כמעט זהה לזו של המינים‬
‫המהגרים (‪ 65.6%‬ו ‪ ,61.3%‬בהתאמה)‪ .‬הדיגניאה הם בעלי מחזור חיים הטרוקסני (מחזור חיים הכולל‬
‫לפחות שני מאכסנים) ולכן הסבירות שיהגרו יחד עם כל מאכסינהם נמוכה יותר‪ .‬מעט במפתיע‪ ,‬לא נמצא‬
‫הבדל מובהק סטטיסטי בין שכיחות ההטפלה ע"י טפילים מקבוצת הדיגניאה במאכסנים פולשים (‪)13.1%‬‬
‫לעומת מאכסנים מקומיים (‪.)8.1%‬‬
‫הדג חשמנון סמית (‪ , (Apogon smithi‬מין מהגר לספסיאני שהתגלה רק לאחרונה‪ ,‬תועד כמין המבסס‬
‫אוכלוסיות בקצב מהיר והופיע ב‪ 35.5%-‬מן הרשתות‪ .‬מין זה הוטפל בשכיחות גבוהה (‪ )52.1%‬בטפילים‬
‫מקבוצות הצסטודות והדיגיניאה‪ .‬כמו כן‪ ,‬בדג החלילן‪ ,Fistularia commersonii ,‬שגם הוא מהגר‬
‫לספסיאני "חדש" יחסית‪ ,‬נמצאה שכיחות גבוהה (‪ )57.9%‬של צסטודות ושל שני מיני דיגיניאה שמוצאם‬
‫באוקיינוס השקט‪.‬‬
‫במחקר זה תואר סוג חדש של מיקרוספורידיה אשר מהווה מקרה ראשון של הדבקה בדגי סחוס‪ .‬הטפיל נמצא‬
‫בטריגון ‪ Dasyatis pastinaca‬במפרץ איסקנדרון שבטורקיה‪.‬‬
‫עדיין חסר לנו מידע בסיסי על הדבקות טפיליות במינים הפולשים בסביבתם הטבעית הים סופית‪ .‬המידע‬
‫המועט העומד לרשותינו כיום מצביע על כך שישנו "שחרור" או הפחתה של טפילים רב תאיים ממיני הדגים‬
‫המהגרים בסביבתה הים תיכונית החדשה‪ ,‬אך הצלחתם באזור החדש לא בהכרח קשורה להיבטים‬
‫הפרזיטולוגיים של תהליך ההגירה‪.‬‬
The effect of a reverse osmosis seawater desalination plant on the marine environment. A
field study at the Israeli Mediterranean coast
Nurit Kress1, Dror Dromi1,2, Yosef Z. Yacobi3, Noga Stambler4
1
Israel Oceanographic and Limnological Research, National Institute of Oceanography,
Haifa. [email protected] 2 The Porter School of Environmental Studied, Tel Aviv
University. [email protected] 3Israel Oceanographic and Limnological Research,
Kinneret Limnological Laboratory. [email protected] 4Mina & Everard Goodman Faculty
of Life Sciences, Bar Ilan University. [email protected]
Global production of freshwater by desalination quadrupled in the last 15 years. In Israel,
seawater reverse osmosis (SWRO) supplies about 17 % of the country’s fresh water demand
and is expected to provide 30% by 2020. While the technological aspects of desalination are
extensively described in the literature, in situ marine environmental studies are lacking. This
study took place at the discharge site of the VID SWRO plant in Ashqelon that started to
operate in 2005, the largest SWRO plant in the world at the time. The plant produces ca.
333,000 m3 d-1 freshwater and discharges brine and backwash of the pre-treatment filters at the
seashore, next to the cooling waters of the Rutenberg power plant. The initial motivation of this
study was the unexpected red plume observed at the outfall site, attributed to the pulsed
discharge of the backwash containing ferric hydroxide, a coagulant used in the pre-treatment
step. The brine, backwash and cooling waters discharges affected seawater quality and the
microbial community at the disposal site. The mixture of the brine with cooling waters was
saltier and warmer than the background, positively buoyant, and dispersed at the surface up to
1,500 m southwards from the outfall. Chlorophyll-a (chl-a) concentration and picoplankton
cells decreased with increased salinity and temperature. Primary production decreased with
increased temperature, similar to chl-a concentration. Bacterial production decreased with
increased salinity. The pulsed backwash discharge increased turbidity, suspended particulate
matter and particulate iron concentrations and tinted the seawater red allowing its visual
tracking. Assimilation number (primary productivity normalized to chl-a concentration)
decreased with increased particulate iron concentration, a proxy to the backwash presence.
‫ניווט ע"י קיטוב אור בים‬
‫‪3‬‬
‫עמית לרנר‪ ,1‬שי סבח‪ ,2‬קרן ארליך‪-‬הספל‪ 1‬ונדב ששר‬
‫‪ 1‬המחלקה למדעי האטמוספרה‪ ,‬האוניברסיטה העברית בירושלים‪ ,91904 ,‬ירושלים‪,‬‬
‫‪[email protected] ,[email protected],‬‬
‫‪ 2‬המחלקה לביולוגיה‪ ,‬אוני' קווינס‪ ,‬אונטריו‪ ,‬קנדה‪[email protected] K7L3N6 ,‬‬
‫‪ 3‬המחלקה למדעי החיים‪ ,‬קמפוס אילת‪ ,‬אוני' בן‪-‬גוריון‪ ,‬אילת‪[email protected] ,88000 ,‬‬
‫ניווט בעזרת קיטוב האור בשמיים ידוע במספר מיני בעלי חיים יבשתיים‪ .‬בים‪ ,‬נמצאו מספר מינים‬
‫המשתמשים בשדה האור המקוטב לצורך אוריינטציה‪ ,‬ואולם האפשרות להשתמש בתבנית הקיטוב התת‪-‬ימי‬
‫כמצפן לצורך ניווט מתחת למים עדיין איננה ברורה‪ .‬על מנת לבחון אפשרות זאת נבדק הקשר בין אחוז וזווית‬
‫הקיטוב התת‪-‬ימי לבין מיקום השמש‪ ,‬בעזרת מודל לחישוב הקיטוב המניח פיזור קרינה ע"י מפזרים‬
‫מולקולאריים (לדוגמא מולקולות המים)‪ ,‬ומדידות של קיטוב האור בים‪ .‬המדידות נערכו בעומקים ‪ ,2‬ו‪ 5-‬מ'‬
‫(עומק תחתית ‪ 6‬מ'‪ ,‬ו‪ 28-‬מ') במים צלולים ועכורים‪ .‬נמצא כי אחוז הקיטוב תלוי במיקום השמש במים‬
‫צלולים בלבד‪ .‬עוד נמצא כי זווית הקיטוב המקסימאלית שנמדדה שווה לזווית השבירה במים‪ ,‬אך קשר זה‬
‫המאפשר ידיעת מיקומה של השמש ומתוך כך שימוש בקיטוב כמצפן‪ ,‬נשמר במים צלולים ובכיוון ראיה‬
‫אופקי בלבד ובעומק התחתית הגדול יותר בלבד‪ .‬אנו מסיקים כי ניווט בעזרת תבנית קיטוב האור במים אפשרי‬
‫במים צלולים בכיוון ראיה אופקי בלבד באזורים שבהם לקרקעית הים השפעה מועטה על תבנית הקיטוב‪.‬‬
Calcein incorporation into the shells of foraminifera: A new tool to study
biomineralization processes in foraminifera
Yael Levenson1, Ahuva Almogi-Labin 2 and Jonathan Erez1
1. Institute of Earth Sciences, the Hebrew University, Jerusalem 91904, Israel
[email protected], [email protected]
2. Geological Survey of Israel, 30 Malkhe Israel, Jerusalem, 95501, Israel
[email protected]
The eukaryotic unicellular marine foraminifera populate most of the oceanic
environments and play a major role in the global carbon cycle. They are major producers
of calcium carbonate (the mineral Calcite) which preserves well in the sediments and
they serve as an excellent tool in paleoceanographic research. Understanding
foraminiferal biomineralization is therefore important both for ocean acidification studies
and in order to wisely and reliably interpret paleoceanographic proxies. The incorporation
of the fluorescent probe Calcein into the shells of live Amphistegina lessonii was studied
using confocal laser microscopy (LSM). Calcein is readily incorporated into newly
precipitated CaCO3 in these foraminifera. This in itself is a surprising observation
because the molecular weight of Calcein is 622 g mol-1 and it is known to be membrane
impermeable. These observations can be explained by seawater vacuolization that supply
Ca2+ and CO32- together with Calcein (and other similar fluorescent dyes) directly into the
site of biomineralization (Erez 2003, Bentov et al 2009). The amount of Calcein
incorporated into the shells is proportional to the calcification measured independently by
direct weighing or by alkalinity depletion. Thus Calcein may be used quantitatively to
estimate calcification rate. However the distribution coefficient of Calcein in foraminifera
is very low in the order of 10-4 with a significant increase with salinity and with
calcification rate. These observations have wide implications for understanding of
Rayleigh type fractionations processes for stable isotopes and trace elements in the
modified seawater calcification reservoirs in foraminifera (sensu Elderfield et al 1996,
Erez 2003, Bentov et al. 2009).
References
Bentov S., Erez, J and Brownlee, C. (2009), The role of seawater endocytosis in the
biomineralization process in calcareous foraminifera, PNAS 106(51) 21500-21504
Elderfield, H., Bertram, C. J. and Erez, J. 1996, A biomineralization model for the
incorporation of trace elements into foraminiferal calcium carbonate. Earth and
Planet. Sci. Lett. 142, 409 - 423.
Erez, J., 2003, The source of ions for biomineralization in foraminifera and their
implications for paleoceanographic proxies. Reviews in Mineralogy and
Geochemistry 54:115-149.
Sea water vacuolization dynamics in benthic foraminifera studied with the
fluorescent probe Calcein
Yael Levenson1, Ahuva Almogi-Labin2 and Jonathan Erez1
1
Institute of Earth Sciences, the Hebrew University, Jerusalem 91904, Israel
[email protected], [email protected]
2
Geological Survey of Israel, 30 Malkhe Israel, Jerusalem, 95501
[email protected]
Foraminifera are giant (up to a few cm in size) marine Protista that are an important
component of the global carbon cycle and their CaCO3 shells which accumulate on the
ocean floor provide highly valuable paleoceanographic information based on its trace
elements and stable isotopes. The ratio of surface area to volume in these organisms is
very low and they have to cope with this problem especially in coastal conditions where
osmotic regulation is needed. We demonstrated recently that these foraminifera
precipitate the bulk of their skeletal calcite from internal seawater vacuoles (Erez 2003,
Bentov et al 2009).
In this study we describe the uptake and release dynamics of vacuolated seawater in the
large benthic foraminifera Amphistegina lobifera and A. lessonii using the membrane
impermeable fluorescent probe Calcein. Using pulse-chase experiments water
vacuolization was detected by Calcein uptake and release using confocal laser
microscopy (LSM). Three different reservoirs of seawater vacuoles were found: A fast
turning over reservoir with residence time (τ) of ~ 20 min., an intermediate reservoir with
τ ~ 6 hr and a long turning reservoir with τ ~ 10 days. The internal volume of seawater
vacuoles is large and exceeds the internal void volume within the skeleton by a factor of
5. The volume of seawater recycled in one day is large enough to provide the Ca2+ and
CO32- for the normal calcification rate. At low salinity (25-20 PSU) the quantity of
Calcein released during the chase is much higher then at normal salinity (35-40 PSU,
factor of 2-6). We propose that this is part of the osmotic regulation process causing
Calcein to concentrate at low salinity as a result of water transport from the vacuoles to
the cytosol. If correct, seawater vacuolization is the main process to increase the surface
area to volume ratio in these foraminifera. For the osmo-regulation process it provides
additional advantage to avoid total volume change, thus providing a unique ecological
advantage to these organisms.
References
Bentov S., Erez, J and Brownlee, C. (2009), The role of seawater endocytosis in the
biomineralization process in calcareous foraminifera, PNAS 106(51) 21500-21504
Erez, J., 2003, The source of ions for biomineralization in foraminifera and their
implications for paleoceanographic proxies. Reviews in Mineralogy and
Geochemistry 54:115-149.
Reductive iron uptake – role in marine phytoplankton
Hagar Lis1,2, Nir Keren3 and Yeala Shaked1,2
1
Institute of Earth Sciences, Hebrew University of Jerusalem
2
The Interuniversity Institute for Marine Sciences in Eilat
3
Institute of Life Sciences, Hebrew University of Jerusalem
Of all the micronutrient metals, iron is the most important limiting nutrient in the ocean.
This study furthers efforts in the investigation of phytoplankton iron acquisition strategies
within the dilute and heterogeneous ocean environment. Our working hypothesis is that
extracellular reduction forms part of the iron acquisition repertoire of most marine
phytoplankton, thanks to its non specific nature. To probe for such a broad based
mechanism, we study the uptake and reduction of free and organically bound iron in a
cross section of representative phytoplankton species. We propose that the reductive
uptake mechanism operates under both high and low iron conditions and thus limited and
non iron limited cells are studied. We extrapolate from monoculture-based studies to
natural phytoplankton assemblages, comparing the kinetic parameters of iron uptake and
reduction across organisms and across Fe-complexes. Preliminary results indicate that a
variety of phytoplankton species including diatoms, cyanobacteria, haptophytes and
green algae reduce free and organically bound iron. While iron uptake rates are distinctly
higher for iron limited organisms, reduction is also observed in non iron-limited cells.
Similar results were found in natural phytoplankton assemblages from high iron
environments which were sampled directly or artificially limited.
Deep sea phenomena in the Israeli Mediterranean: research and implications
Yizhaq Makovsky
Dr. Moses Strauss Department of Marine Geosciences, Charney School of Marine
Sciences (CSMS), University of Haifa, Haifa 31905, Israel. [email protected]
Recent substantial offshore gas finds in the Israeli Mediterranean constitute a historical
geopolitical turning point for the future of Israel. These finds prompt a national
awareness and official declaration of the Mediterranean Exclusive Economic Zone (EEZ)
of Israel, more than doubling the area of Israel itself. The upcoming development of deep
sea reservoirs already involves infrastructure, means and investments large at worldwide
standards. Mundane as it seems when looking from the coast, the Israeli Mediterranean
poses significant challenges in the face of development. In particular, the entire
Mediterranean continental slope offshore Israel is subjected to apparently active
gravitational collapse due to ~2 km deep salt deformation; and is etched by a multitude of
small scale (~5 km wide) apparently recent mudslide scars. The actual rate of activity of
these features has not been constrained as of yet. High resolution acoustic sub-bottom
profiles and bathymetry, acquired by Oceana in the course of Tamar alternative piperoutes survey and analyzed by us, reveal: steep sub-marine steps – an evidence for active
gravitational collapse; and association of most recent deformation fronts with gas
accumulations in the sediments – a possible promoting factor for sliding. A two weeks
cruise in September 2010 onboard the Ocean Exploration Trust E/V Nautilus collected
high definition video, hand and short core samples and sidescan sonar data at water
depths of 500 to 1700 m of the Israeli Mediterranean utilizing the vessel’s state-of-the-art
ROV operation. The cruise was led by a combined team of the Institute For Exploration,
Charney School of Marine Sciences, Israel Oceanographic and Limnological Research
and the Geological Survey of Israel. Some of the main finds were seafloor holes
reminiscent of sinkholes at a depth of ~1100 m; up to ~20 high sheer escarpments
suggesting active faulting, presumably related with salt collapse; and deep sea reefs rich
with deep water fauna, and particularly abundant with Antipatharian colonies. While still
preliminary, our results demonstrate the need for in-depth deep sea research as a base for
sustainable development of the Israeli Mediterranean EEZ.
‫פתיחתם וסגירתם של האגנים בשולי האוקיאנוס – ניסויים במודל אנלוגי‬
‫יוסי מרט‬
‫מכון רקנאטי ללימודי ים‪ ,‬אוניברסיטת חיפה‪ ,‬חיפה ‪)[email protected] 31905‬‬
‫קיומם של אגני שוליים מדרום לים טתיס במהלך המסוזואיקון מעסיק את הקהילה הגאולוגית שנים רבות ללא‬
‫פתרון ברור‪ ,‬וקיומם של תהליכי הפחתה כלפי דרום מם נושא השנוי במחלוקת‪ .‬מודלים אנלוגיים של השלבים‬
‫הראשוניים בהפחתת הליתוספרה הימית אל תוך האסתנוספרה והיווצרות אגני השוליים מראים כיצד משפיע‬
‫החיכוך‪ ,‬הכרוך בתהליך ההפחתה‪ ,‬על עיצוב ההתמוטטות של שולי היבשת וקריסתם אל האוקיאנוס‪ ,‬כאשר‬
‫בתנאים של חיכוך נמוך מביאה הקריסה לביקוע של אגנים בעלי קרקעית מאגמתית בשולי האוקיאנוס‪ ,‬בדומה‬
‫לאגנים המצויים במערב האוקיאנוס השקט‪ .‬אגני שוליים אינם יציבים תמיד‪ ,‬אלא הם עשויי להוות מבנה‬
‫גאולוגי חולף‪ .‬מחקרים גאולוגיים שבוצעו במערב אירלנד על ידי ג'והן דיואי (‪ ) Dewey‬וחובריו הצביעו על‬
‫הזמן הקצר בו נסגר אגן שוליים בתקופת האורדוביק‪ ,‬לפני כ‪ 450-‬מיליון שנה‪ .‬מודלים אנלוגיים שהורצו‬
‫בצנטריפוגה גדולה הראו כי התפתחות אגן השוליים כרוכה בקריעה של חלק נרחב משולי היבשת והפיכתו‬
‫לקשת איים‪ .‬עם הזמן מוסעת קשת האיים הזאת אל האוקיאנוס‪ ,‬תוך גלילה משמעותית של איזור ההפחתה‬
‫מהיבשת והלאה‪ .‬בבניה ניסיונית של אגן השוליים התקיימו שלושה אזורי מגע בין הליתוספרות הימית‬
‫והיבשתית – בין האוקיאנוס וקשת האיים‪ ,‬בין הקשת ואגן השוליים ובין אגן השוליים והיבשת (איור ‪1‬‬
‫עליון)‪ .‬מאחר והליתוספרות היבשתיות שונות זו מהימיות בצפיפותן‪ ,‬בהרכבן ובצמיגותן‪ ,‬סביר להניח כי‬
‫אזורי המגע ביניהן יהוו‪ ,‬עם הזמן‪ ,‬אזורי הפחתה‪ .‬לאחרונה נעשה ניסיון לבחון איך תתפתח ההפחתה במערכת‬
‫של אגן שוליים וקשת איים על ידי הצבת המודל האנלוגי בצנטריפוגה גדולה בתאוצה של ‪( g 800‬איור ‪.)1‬‬
‫נמצא כי ההפחתה החלה בשלושת אזורי המגע בין הליתוספרות‪ ,‬אבל כאשר החלה הפחתה משמעותית של‬
‫קרקעית אגן השוליים כלפי היבשת נעצרו ההפחתות האחרות‪ .‬עם התקדמות ההפחתה הפעילה קרסו שולי‬
‫היבשת והתמוטטו על גבי הליתוספרה של אגן השוליים‪ ,‬תוך כדי חשיפה של גג המעטפת על פני אזור נרחב‪,‬‬
‫כלומר בטבע היה מדובר כנראה בחשיפה של סלעים מטמורפיים‪ .‬מאחר וממדי אגן השוליים מטבעם אינם‬
‫גדולים‪ ,‬חלפה המאסה היבשתית‪ ,‬שכללה את הקרום ואת המעטפת העליונה‪ ,‬את כל אגן השוליים והתנגשה‬
‫בקשת האיים‪ .‬המאמצים שהפעילו הליתוספרות היבשתיות זו על זו הביא למעוותים של לחיצה‪ ,‬ליצירת‬
‫קימוטים ולדחיפה של פיסת מעטפת אל פני השטח‪ ,‬בדומה לדיאפיר של אופיוליט‪ .‬מעניין לציין כי בניסיונות‬
‫האלה לא חל מהפך בכיוון ההפחתה‪ ,‬כפי שאכן קרה באירלנד באורדוביק‪.‬‬
‫איור ‪ .1‬הצבת ניסיון של הפחתה של ליתוספרה של אגן שוליים בצנטריפוגה‪ ,‬כאשר הליתוספרות היבשתיות‬
‫כהות והימיות – בהירות‪ .‬איור עליון – מצב התחלתי‪ :‬היבשת היא משמאל‪ ,‬האוקיאנוס מימין‪ ,‬וביניהם קשת‬
‫איים (כהה) ואגן שוליים (בהיר)‪ .‬איור תחתון – מצב סיום‪ :‬היבשת וקשת האיים מתנגשות‪ .‬שימו לב למקטע‬
‫השחור המחוספס בצידו השמאלי של האיור התחתון‪ .‬הוא מסמן סלעים מטמורפיים בגג המעטפת שנחשפה‪.‬‬
‫"מדוזות ברשת"‪ ,‬השפעתן של מדוזות על ענף הדיג‪ :‬ניתוח כלכלי‬
‫‪3‬‬
‫נעה נקאר‪ ,1‬דרור אנג'ל‪ 2,1‬ודפנה דיסני‬
‫‪1‬החוג לציוויליזציות ימיות‪ ,‬אוניברסיטת חיפה‪ ,‬הר הכרמל חיפה ‪[email protected] 31905‬‬
‫‪2‬המכון ללימודי ים‪ ,‬אוניברסיטת חיפה‬
‫‪3‬החוג לניהול משאבי טבע‪ ,‬אוניברסיטת חיפה‬
‫בשנים האחרונות קיימת השערה כי אוכלוסיית המדוזות הולכת וגדלה בקנה מידה עולמי‪ .‬עיקר ביסוסה של‬
‫השערה זו נובע מדיווחים הולכים וגוברים של פגיעה במתרחצים ומעורבות הולכת וגדלה של מדוזות בפעילות‬
‫דייגים ותחנות כוח‪ .‬רוב המחקרים שעסקו בפגיעה הקיימת בענף הדיג ממדוזות‪ ,‬ציינו את הפגיעה‬
‫האינטנסיבית‪ ,‬אך לא אמדו את הנזק הכלכלי הטמון בכך‪ .‬חלקם אמנם הציגו הערכה כלכלית גסה‪ ,‬אך ללא‬
‫חישוב כמותי ברור לנזק נשוא העניין‪.‬‬
‫הפגיעה בענף הדיג עשויה להתרחש בשני מישורים‪ -‬ישיר ועקיף‪ .‬באופן ישיר עקב פגיעה בציוד הדיג‬
‫והשבתת ימי דיג ובאופן עקיף נוכחותן של מדוזות משנה את מארג המזון ובשל כך פוגעת בדגים הנמצאים‬
‫בים‪.‬‬
‫מטרת מחקר זה הינה לאמוד באמצעות מודל כלכלי את ההשפעה של מדוזות על ענף הדיג‪ .‬מודל זה כולל את‬
‫אומדן הפגיעה הישירה בלבד ומפנים גם את ההשפעה העקיפה של מדוזות על הדגה בים‪.‬‬
‫המודל המוצע כולל מספר הנחות חזקות ביחס למערכת הביולוגית‪ ,‬שהוכתבו בשל מגבלת נתונים על המערכת‬
‫הקיימת‪ ,‬כגון קצב תמותה‪ ,‬התחדשות דגה על פי מין ועוד‪ .‬בהמשך‪ ,‬כאשר יתווספו הנתונים הביולוגיים‬
‫הנוספים‪ ,‬יוכל המודל המוצע להפנים את האינפורמציה החדשה ולתת אומדן לנזקים בענף הדיג כתוצאה‬
‫ממדוזות באופן פרטי מדויק יותר (הן ביחס לאמידת ההשפעה העקיפה ממדוזות והן ביחס להשפעה של מדוזות‬
‫על מיני דגים שונים בסל הדיג)‪.‬‬
‫הפרמטרים ששימשו למחקר נאספו משני מקורות עיקריים‪ -‬נתוני אגף הדיג‪ ,‬ונתונים שנאספו במהלך שנת‬
‫‪ 2010‬באמצעות שאלונים וראיונות אישיים עם דייגים לצורך לימוד התנהגות הדייגים ואמידת הנזק המתרחש‬
‫ממדוזות‪.‬‬
‫עיקר הנזק‪ ,‬כפי שהשתקף במודל‪ ,‬התבטא בפרמטר אותו כינינו כ "אפקטיביות מאמץ הדיג"‪ ,‬כאשר נוכחותן‬
‫של מדוזות הפחיתה את יעילות מאמץ הדיג ובכך השפיעה על תפוקת הדיג‪ .‬פרמטרים נוספים שהעידו על‬
‫פגיעה קשורים לנזקים בציוד הדיג‪ ,‬הנכללת בעלויות הדיג ופגיעה בימי היציאה לים‪ ,‬המשפיעה על פוטנציאל‬
‫ימי הדיג‪.‬‬
‫הספינה הטרופה דור ‪2006‬‬
‫ריקה נברי‬
‫המכון ללימודי ים ע"ש ליאון רקנאטי והחוג לציוויליזציות ימיות‪ ,‬אוניברסיטת חיפה‬
‫חיפה‪ ,‬הר הכרמל ‪31905‬‬
‫הספינה הטרופה דור ‪ 2006‬התגלתה על ידי דייג מקומי בשם דוד עבדה כ‪ 800-‬מטרים דרומית ללגונה של‬
‫דור‪/‬טנטורה במרחק של כ‪ 100-‬מטרים מהחוף‪ .‬שרידי הספינה נסקרו בצלילה קצרה‪ ,‬בה אובחנו לוחות‪,‬‬
‫צלעות וחלק שעשוי להיות תורן‪ .‬דגימות עץ שנלקחו תוארכו באמצעות פחמן ‪ 14‬למאה החמישית לספירה‪,‬‬
‫התקופה הביזנטית באזורינו‪.‬‬
‫עד כה נערכו שתי עונות חפירה על ידי המכון ללימודי ים ע"ש לאון רקנאטי באוניברסיטת חיפה‪ .‬החפירות‬
‫נערכו בתנאי ים קשים‪ ,‬היות שמדובר באתר הנמצא בקו משברי הגלים ובים פתוח‪ ,‬כלומר באתר רגיש מאוד‬
‫לתנאי הים והרוח‪ .‬כדי לאפשר קיום חפירה ארכיאולוגית תת‪-‬ימית באתר זה‪ ,‬נדרש ים שקט‪ .‬בעת הפסקת‬
‫העבודה בגלל תנאי הים‪ ,‬הגלים והזרמים ממלאים את אתר החפירה בחול‪ ,‬ויש להתחיל את החפירה‬
‫מההתחלה‪ .‬כעשרה ימים מתוך שלושה וחצי שבועות של כל עונת חפירה הושבתו בגלל תנאי מזג האוויר‪ ,‬אך‬
‫למרות זאת היו שתי עונות מוצלחות בהן נאספו נתונים רבים‪.‬‬
‫בחפירות נחשפו שרידי ספינה הכוללים צלעות‪ ,‬לוחות גוף‪ ,‬לוחות רצפה וחלקי עץ שונים‪ .‬מבדיקה של‬
‫הממצאים עולה כי ככל הנראה המדובר בספינה גדולה ושונה מהספינות שנחפרו עד כה בלגונה של‬
‫דור‪/‬טנטורה‪ .‬הנתונים הראשוניים הם של כ‪ 26-‬לוחות גוף‪ ,‬מהם חמש לזבזות עשויות מחצי גזע עץ; ‪42‬‬
‫חלקי צלעות‪ ,‬ביניהן צלעות מסיביות מאוד‪ ,‬שרוחבן משתנה בין ‪ 23─18‬ס"מ ועוביין משתנה בין ‪35─23‬‬
‫ס"מ; וכמו כן נמצאו שמונה לוחות רצפה אף הם עבים ורחבים‪ ,‬ארבעה מהם עשויים מחצי גזע עץ‪.‬‬
‫בשונה מהממצאים שנחשפו עד היום בדור‪ ,‬של כלי שיט קטנים‪ ,‬חופיים‪ ,‬שנבנו על בסיס הצלעות‪ ,‬אנו מוצאים‬
‫בשרידי הספינה הטרופה הזו עדויות לחיבורים בין הלוחות‪ .‬התמונה הכללית היא של כלי שיט גדול‬
‫מאוד‪,‬אשר שיטת בנייתו הסתמכה גם על חיבורים בין לוחות הגוף לבין עצמם‪ .‬מכאן ייחודה וחשיבותה‬
‫למחקר‪.‬‬
Combining science and leisure: the role of marine exploration tourism for different
stakeholder groups
Philip Nemoy
Department of Maritime Civilizations, University of Haifa, Mount Carmel, Haifa 31905,
[email protected]
Marine Exploration Tourism (MET) can be seen as a part of ecotourism, a growing
branch of tourism industry, oriented on combining leisure, education and work at sea. By
participating in marine explorations various stakeholder groups achieve mutual benefit:
Public sector: meets the need for active recreation, combined with training and
experience in scientific research.
Commercial sector (ecotourism operators, including non-profit organizations whose
primary goal is conservation of marine environment): develop "sustainable tourism",
which is economically viable but does not destroy the resources on which the future of
tourism will depend, notably the physical environment and the social fabric of host
communities.
Academia: benefits from research funding, volunteer labor and interactions with
volunteers and general public.
In addition to statistical data regarding the scopes and the outcomes of MET in recent
years, I want to present a case study, the Research Vessel Heraclitus. The ship has more
than 35 years of almost constant sailing. Its previous expeditions were oriented at
ethnobotany (Amazon Expedition), coral reefs (Coral Sea Expedition), cetaceans,
wastewater impact on coastlines and sea people studies. RV Heraclitus and its parent
organization, the Institute of Ecotechnics (Santa Fe, New Mexico, US), are engaged in an
expedition 2010-2013 (Mediterranean Expedition), exploring the contemporary history of
peoples in Mediterranean port cities. It offers the Sea People Program, which includes
building basic seamanship skills, participation in onboard scientific studies and in theatre
arts workshops, as a part of cultural exchange with host communities. Participation in RV
Heraclitus expedition is on voluntary basis and travel expenses are covered by the
participants. RV Heraclitus is seeking for cooperation with academic institutions and
offers a platform for various marine-oriented researches.
In conclusion, I want to bring the attention of the Israeli Association of Aquatic Sciences
members, senior researchers and students alike, to the resources of marine exploration
tourism for the benefit of different stakeholders in Israeli coastal waters and abroad.
‫השינוי במאספי פורמיניפרים בנתונים בתגובה לפינוי כלובי הדגים במפרץ אילת ‪ -‬עקבה‬
‫שי אורון‪ ,1,3‬גילי מרקדו‪ ,1‬סיגל אברמוביץ‪ ,1‬בברלי גודמן צ'רנוב‪ ,2‬משה כפלאוי‪ ,1,3‬דרור אנג'ל‬
‫‪2‬‬
‫‪1‬‬
‫‪1‬אוניברסיטת בן גוריון בנגב ‪[email protected]‬‬
‫‪2‬אוניברסיטת חיפה‬
‫‪3‬המכון הבינאוניברסיטאי באילת‬
‫חלק ניכר מתעשיית הדגים בעולם מבוססת כיום על גידול דגים בכלובים‪ ,‬הממוקמים לרוב באזורים הסמוכים‬
‫לחוף‪ .‬למתקנים אלה ישנה השפעה ניכרת על הסביבה הימית באזור הכלובים‪ ,‬בעיקר בשל השחרור המוגבר‬
‫של תרכובות אורגניות ונוטריינטים העלול לגרום לאאוטריפיקציה (‪ )eutrophoication‬בגוף המים וליצירת‬
‫תנאים אנוקסים בסדימנט‪ .‬במפרץ אילת התקיימה חקלאות ימית של גידול דגים בכלובים במשך כ‪ 18‬שנים‪.‬‬
‫חוות הדגים מוקמו באזור החוף הצפוני במרחק של כ ‪ 300‬מטרים מהחוף‪ .‬החשש לפגיעה הפוטנציאלית של‬
‫כלובי הדגים במערכת האקולוגית של המפרץ ובסביבה החופית היה במרכזו של ויכוח מדעי‪ ,‬משפטי וציבורי‬
‫שבעקבותיו הורתה המועצה הארצית לתכנון ובנייה על פינוי הכלובים‪ ,‬שהושלם בחודש יוני ‪ .2008‬הפסקת‬
‫פעילותם של כלובי הדגים יצרה הזדמנות ייחודית לחקור את תהליך השיקום של אוכלוסיות פורמינפרים‬
‫בנתונים‪ ,‬הידועים כסמנים אקולוגיים רגישים‪ .‬המעקב נעשה על ידי דיגום חודשי שהחל ביולי ‪ ,2008‬ונמשך‬
‫עד יולי ‪ ,2010‬של גלעיני סדימנט קצרים מתחנות קבועות המייצגות מרחקים שונים מאזור הפעילות של חוות‬
‫הדגים‪ ,‬ודיגום עלים ושורשים מעשב הים ‪ Halophila stipulacea‬אשר הופיע באזור המחקר באוגוסט‬
‫‪.2009‬‬
‫תוצאות המחקר מראות כי ההעשרה האורגנית מכלובי הדגים גרמה ליצירת איזור אזואי (חסר חיים)‬
‫בסביבתם המיידית‪ ,‬אשר התנאים בו לא אפשרו קיום פורמיניפרים חיים‪ ,‬עד לתקופה של כשנה לאחר פינוי‬
‫הכלובים‪ .‬המאסף המת מראה הצטברות מאסיבית של שלדים השייכים לעשרות מינים שונים אשר אכלסו את‬
‫האזור בעבר‪ .‬בחודש מאי ‪ 2008‬החלו להופיע פרטים חיים של פורמיניפרים השייכים בעיקר לקבוצת‬
‫הנומוליטים (‪ ,)Nummulitids‬כאשר בחודשי השיקום הראשונים מספרי הפרטים החיים בתחנות הדיגום‬
‫המרוחקת יותר מ ‪ 40‬מטרים ממיקום הכלובים היו גדולים באופן מובהק מאלה בתחנות הסמוכות למיקום‬
‫הכלובים‪ .‬אפיון של מאספי הפורמיניפרה על עלי עשב הים ‪ .H. stipulacea‬הראה דמיון למאספים המתים‪,‬‬
‫עובדה התומכת בהשערה כי מקורם של המאספים המתים הוא בעשבי הים אשר היוו מרכיב אקולוגי חשוב‬
‫באזור לפני ההעשרה האורגנית‪.‬‬
Dead Sea - Red Sea and Dead Sea - Mediterranean Sea connections on 17th-19th
century maps of the Holy Land
Aharon Oren
Department of Plant and Environmental Sciences, The Institute of Life Sciences, The
Hebrew University of Jerusalem, 91904 Jerusalem [email protected]
Since the planning of a connection between the Mediterranean and the Dead Sea in the
1970s-1980 and the current plans to connect the Red Sea with the Dead Sea, we are
familiar with the idea of using seawater to generate energy and improve the infrastructure
of the Dead Sea area. However, it is little known that Dead Sea – Red Sea and Dead Sea
– Mediterranean Sea connections already featured on maps in the 17th-19th century. A
map published in 1664 by the Jesuit priest Athanasius Kircher in his 'Mundus
subterraneus' shows an underground connection ("Canalis subterranea bituminosa")
between the Dead Sea and the Red Sea. It also shows a connection ("Canalis
subterraneus") between the northern Red Sea and the Mediterranean Sea, the site of the
Suez Canal. Kircher never visited the area, but the accompanying text provides intriguing
information to support his speculations. A map showing the Dead Sea connected with
both the Mediterranean Sea and the Red Sea was presented in 1855 by Captain William
Allen, British Royal Navy, in his book “The Dead Sea, a new route to India”. As
alternative to the planned Suez Canal, Allen proposed two canals, from Haifa bay
eastward and from Aqaba up north, so that the Dead Sea, the entire Jordan Valley and the
Arava Valley would fill up, opening a “means of communication with our East Indian
possessions”. The idea of a Mediterranean – Dead Sea connection to produce
hydroelectric energy, exploiting the difference in elevation (then 394 m, currently 424
m), first appeared on a map drawn in 1899 by the Swiss engineer Abraham Max Bourcart
who surveyed the area to advance the Zionist idea. Bourcart’s concepts were used by
Herzl in his novel “Altneuland” and form the basis for the recent plans for the restoration
of the Dead Sea water level.
Oceanographic equipment used in Dead Sea explorations in the middle of the
19th century
Aharon Oren
Department of Plant and Environmental Sciences, The Institute of Life Sciences, The
Hebrew University of Jerusalem, 91904 Jerusalem [email protected]
The first oceanographic exploration of the Dead Sea was held in April-May 1848 and led
by Lt. William Francis Lynch, U.S. Navy. Soundings in the deepest part yielded values of
336-357 m, but one single sounding showed 218 fathoms (399 m). To collect deep water
and sediments, Lynch used a sampler developed a few years earlier by Henry Stellwagen.
It consisted of a conical steel cup with a valve lined with leather that sealed the cup as the
line was hauled in. The Lynch expedition measured temperatures in the water column
using a "self-registering thermometer", and reported the existence of a temperature
minimum at a depth of 10 fathoms (18 m). No information was provided about the make
and the mode of action of the instrument. "Registering thermometers" or minimummaximum thermometers were invented by James Six in 1780. However, it is not clear
how such an instrument could monitor a cold water layer between two warmer layers.
Reversing thermometers became popular in oceanographic studies only in the end of the
19th century. The prototype was constructed in 1841 by George Aimé, and an instrument
for routine oceanographic use was not developed until the 1870s. State-of-the-art
instrumentation was used on the Dead Sea in March-April 1864 by the duc de Luynes,
accompanied by geologist Louis Lartet. The especially designed sampler consisted of an
iron tube containing a test tube filled with mercury, and connected to a conical cup which
collects the mercury from the tube when it is inverted by operation of a triggering device.
The sampler was deployed from a 9.5-meter sailing yacht. Using this instrument the first
density profile of the Dead Sea water column was measured (from 1.160 g/ml at the
surface to 1.230 g/l near the bottom). Some samples recovered were also subjected to
chemical analysis.
Influence of radiation levels on coral bleaching in the age of global warming
Marina Polak1, Oren Levy1 and Maoz Fine1,2
1
The Mina & Everard Goodman Faculty of Life Science, Bar-Ilan University, Ramat-Gan
52900, Israel. [email protected]
2
The Interuniversity Institute for Marine Science, Eilat 88103, Israel.
Coral reefs are the most beautiful and diverse ecosystem known today. Their significance
is not only due to their ability to support thousands of different species, but is also due to
their role as a natural barrier, protecting shore line from erosion and destruction. Darwin,
during his voyage on the Beagle, describes tropical coral reef as oases in the desert of the
ocean and was amazed by the ability of the coral reefs to flourish surrounded by
oligotrophic waters. Mayer (1914),Yonge (1940) and other earliest scientists working on
corals, solved the mystery behind the success these animals by describing their symbiosis
with endosymbiotic algae .
During the last century, bleaching events started to be documented since 1980s, although
there were few reports about coral bleaching in the 60s and 70s and even in earliest 30s.
Following coral bleaching events and their mortality, this study issue found a central
place in the research of leading scientists all over the world. It has been shown that brake
down of the symbiosis between corals and zoothantellae, or the bleaching effect, is
influenced by a synergistic effect of thermal stress and solar radiation.
The aim of this study is to examine the influence of both factors simultaneously on
common branched corals Stylophora pistillata and Acropora eurystoma. Corals were
exposed to elevated temperature ranged from 280C to 340C under different intensities of
solar radiation, using shading nets with different percentage of penetration. Samples were
collected at four different temperatures (280C,300C,320C and 340C), and standard
physiological tests such as chlorophyll , protein levels, and zoothantellae count had been
used to determine the differences between the treatments.
Our results confirms that corals found in more shaded conditions are more stable and tend
to loose their endosymbionts at much higher temperatures than those found in the shallow
water. How ever, during the experiment period, loss of zoothanthellae never exceeded
50% compared to the beginning of the experiment. From these new results, we can
conclude that the corals present in the gulf of Eilat, are more robust to high temperatures,
which can exceed approximately 60C above summer maxima, than corals that flourish in
Indian and the Pacific oceans. In contrary to nowadays concern about predicted sea level
rise, as a result of global warming, this study shows that increase of the water column
above the coral reefs may serve as a refuge, and hence reduces the possibility for the
creation of a devastating affect of radiation-temperature combination by reducing solar
radiation in the equation.
An ecosystem unfolds: spatiotemporal biodiversity patterns on Israeli Mediterranean
vermetid reefs
Gil Rilov
National Institute of Oceanography, Israel Oceanographic and Limnological Research, PO Box
8030, Haifa, 31080 [email protected]
Set at the eastern-most part of the Mediterranean, the Levant holds a unique rocky intertidal
ecosystem called “vermetid reefs” found only in hot temperate seas. These are broad sedimentaryrock platforms that are formed by the buildup of a calcareous crust of aggregative, intertidal,
sedentary vermetid snails that reduces rock erosion at mid sea level. The unique ecosystem that
forms on these platforms is facing increasing threats to its ecological integrity including climate
change and bioinvasions. Nevertheless, the biodiversity patterns and the ecological processes that
shape its communities are poorly known. In late 2009, a monitoring program has started in order
to unveil the spatiotemporal patterns of the ecological communities in this ecosystem and to
predict their future in light of the threats. Eleven sites are surveyed north-to-south annually along
transects at different shore levels, and four core sites are surveyed seasonally. At the core sites,
temperature is continuously logged and chlorophyll and nutrient levels are sampled monthly.
Results show high variability of community structure among sites, with no clear north-to-south
patterns. Most apparent is the unexplained and worrying extinction of Dendropoma petraeum, the
main vermetid species. Also apparent is the mosaic cover of an invasive Red Sea mussel that
cannot be explained by differential predation or larval recruitment rates. We also found a strong a
seasonal signal in community patterns.
The seaward edge of the platforms holds the highest species richness, and preliminary surveys
indicate that diversity is much higher on platform tops than on more submerged horizontal rocks
10-50 cm below them. This observation renders one disturbing prediction: inundation of the
platform flats by sea level rise that is >10 cm would cause a big drop in rocky shore biodiversity
because new platforms at higher levels of the new coastline will not be created due to the
Dendropoma extinction.
‫ביולוגיה ואקולוגיה של בינון הירדן (‪)Nemacheilus jordanicus‬‬
‫בת שבע רוטמן ומנחם גורן‬
‫המחלקה לזואולוגיה‪ ,‬אוניברסיטת תל אביב‪ ,‬תל אביב ‪69978‬‬
‫‪[email protected] [email protected],‬‬
‫משפחת הבינוניים ‪ Balitoridae‬מונה מאות מינים‪ ,‬המאכלסים את מערכות המים הפנימיים באירואסיה‪ .‬מעט‬
‫מאוד ידוע על הביולוגיה והאקולוגיה שלהם וקיימת אי ודאות רבה בנוגע למעמד הסיסטמאתי של מרביתם‪.‬‬
‫במערכת הירדן מצויים היום ארבעה מיני בינונים‪ ,‬שלושה מהם מאוימים ומין אחד‪ ,‬בינון דור‪ ,‬בסכנת הכחדה‬
‫חמורה‪ .‬מין נוסף‪ ,‬נון החולה נעלם מהאזור לאחר ייבוש החולה בשנות ה‪ 50-‬במאה הקודמת‪ .‬בינון‬
‫הירדן ‪ Nemacheilus jordanicus‬הוא כנראה מין אנדמי למערכת הירדן‪ .‬ההערכה היא שחלה ירידה של‬
‫כ‪ 50%-‬בגודל האוכלוסייה בין השנים ‪ 1996‬ל‪ 2006 -‬והוא מוגדר בסכנת הכחדה (‪ )EN‬לפי ה‪.IUCN-‬‬
‫במסגרת המחקר הנוכחי נבחנו היבטים שונים בביולוגיה ובאקולוגיה של בינון הירדן‪ .‬המחקר מבוסס על‬
‫דיגומים חודשיים שנערכו בשנים ‪ 2008-2007‬במעיינות הבניאס ועל מערכות ניסוי שהוקמו במעבדה‬
‫האיכטיולוגית באוניברסיטת ת"א‪.‬‬
‫בהשוואה בין זכרים לנקבות נמצאו הבדלים במצבם הגופני‪ ,‬בקצב הגדילה ובגיל ההבשלה הרבייתית‪ ,‬ויחס‬
‫הזוויגים באוכלוסיה נמצא מוטה לנקבות‪ .‬בדומה להערכות קודמות‪ ,‬נמצא כי עיקר עונת הרבייה בבינון הירדן‬
‫חלה בין מרץ ליוני‪ ,‬אך נקבות בשלות להטלה נמצאו מינואר ועד יולי‪ .‬עונת הרבייה הארוכה במהלכה נראו‬
‫ירידות ועליות באינדקס הגונדו‪-‬סומטי‪ ,(GSI(-‬ומציאת אוכלוסיה הטרוגנית של אואוציטים בשחלה מעידים‬
‫על כך שנקבות מטילות מספר דורות של ביצים בעונה (‪ .)multiple spawner‬השינוי העונתי שחל במצב‬
‫הרבייתי היה הופכי לשינוי העונתי במצב הגופני ומצביע על המחיר האנרגטי הכרוך בפעילות הרבייתית‪.‬‬
‫מחיר זה ככל הנראה משפיע על קצב גדילתן של הנקבות עם הגיען לבגרות רבייתית‪.‬‬
‫בניסיון לקבוע איזו השפעה יש לטמפרטורה על עונתיות הרבייה בבינון הירדן הוקמה מערכת ניסוי במעבדה‬
‫שהראתה כי הרבייה מתרחשת במים קרים בלבד‪ .‬לא ניתן היה לקבוע כי שינוי עונתי בטמפרטורה משפיע על‬
‫עונתיות הרבייה‪ .‬עם זאת‪ ,‬הימצאות הדגים במים קרים יכולה להוות תנאי בסיסי להתפתחות הגונדות‪.‬‬
‫תוצאות המחקר תרמו לידע המועט על אודות אורח החיים של בינון הירדן ומאפייני הרבייה על היבטם‬
‫השונים‪ ,‬ויוכלו לשמש ככלים עתידיים לשימורו ואולי לצמצם בעתיד את דעיכת האוכלוסיות כפי שנצפתה עד‬
‫כה‪.‬‬
Keep and Touch – Dust and mineral iron utilization by the marine diazotroph
Trichodesmium
Maxim Rubin1,2, Ilana Berman-Frank2, Yeala Shaked1,3
1
Interuniversity Institute for Marine Sciences, Eilat, 88103.
Mina & Everard Goodman Faculty of Life Sciences, Bar Ilan University, Ramat Gan,
52900.
3
The Fredy and Nadine Herrmann Institute of Earth Sciences, The Hebrew University,
Jerusalem, 91904.
2
Oceanic blooms of Trichodesmium, a filamentous N2 fixing cyanobacterium, provide ~50%
of the new nitrogen sources to subtropical and tropical areas, fueling primary production and
influencing nutrient flow and biogeochemical cycling of organic and inorganic matter1,2.
The extensive surface blooms require large inputs of iron that are partly supplied by aeolian
dust sources, yet the processes and mechanisms associated with dust acquisition are
currently poorly defined. Here we explore the sequence of steps by which natural
populations and laboratory cultures of Trichodesmium collect, process, and utilize iron from
synthetic iron oxides and desert dust. We find that, similar to most phytoplankton, solidphase iron has to dissolve prior to its acquisition by Trichodesmium, and that the mineral
dissolution has to occur on the cell-surface rather than in the bulk medium to result in
uptake. We show that, unlike other studied phytoplankton, Trichodesmium apply cellsurface processes that accelerate the dissolution rate of iron oxides and dust above that of
the minerals' self-dissolution, thereby enhancing their bioavailability. The ability to retain
and subsequently dissolve experimentally added dust and iron oxides vary among
Trichodesmium morphologies. Natural puff colonies are particularly effective in dissolving
dust, probably due to its efficient trapping within the intricate colony morphology, followed
by active centering and packaging of the dust within the colony core. Thus, in
Trichodesmium and other large colonial phytoplankton, colony formation may provide an
advantageous strategy for accessing iron and other nutrients (e.g. P) from particulate sources
such as dust.
The ecological and economical effect of recreational fishing in the eastern basin of
the Mediterranean Sea
Doron Schultz1, Yehuda Benayahu1 and Aliza Fleischer2
1
Zoology Department, Faculty of Life Sciences, Tel Aviv University
2
Department of Agricultural Economics and Management, Faculty of Agriculture, the
Hebrew University, Jerusalem.
In recent years, many studies have shown a sharp increase in recreational fishing activity
in the western world (USA, Europe, Australia). This increase has contradictory effects,
on the one hand, recreational fishing has a significant contribution to the state's economy.
On the other hand, various sport fisherman's activities Found to be destructive to the
marine fauna, if they are not regulated. Unlike other countries, Israel has no regulatory or
management protocols for the sport-fishing industry. Therefore, the main purpose of this
study is to provide the policy-makers for the first time with information that will lead to
sustainable, well- regulated, recreational fishing activities. Thorough examination of the
ecological impacts and economic potential of recreational fishing, including consumer
surplus and state revenues, will enable formulation of recommendations for effective
regulation of this type of fishing and the prevention of irreversible environmental
damage. The resulting proposed solutions are expected, therefore, to improve social
welfare, both in terms of preserving an important natural resource and in economic terms.
‫אוכלוסיות הצדפה "תמר הים" ‪ Lithophaga lithophaga‬בחוף הים תיכוני הישראלי‪ :‬ניצול בקשוות‬
‫הצדפות המהגרות ‪ Spondylus spinosus‬ו‪Chama pacifica-‬‬
‫‪1‬‬
‫עתרת שבתאי‪ ,1‬ענבר שוורץ‪ ,1‬גיל רילוב‪ ,2‬יהודה בניהו‬
‫‪1‬המחלקה לזואולוגיה‪ ,‬אוניברסיטת תל אביב‪ ,‬רמת אביב ‪[email protected] 69978‬‬
‫‪2‬המכון הלאומי לאוקיאנוגרפיה‪ ,‬שקמונה‪ ,‬חיפה‬
‫אוכלוסיות הצדפה הקודחת ‪ Lithophaga lithophaga‬הידלדלה באגן המערבי והמרכזי של הים התיכון‬
‫באופן משמעותי כתוצאה מניצול יתר על ידי האדם‪ .‬סלעי הגיר‪ ,‬המהווים את בית הגידול העיקרי של הצדפה‪,‬‬
‫נהרסו במקומות רבים עקב שליית הצדפה לתעשיית המזון‪ .‬סקירת ספרות מראה‪ ,‬כי לא נערכו מחקרים על‬
‫אוכלוסיות הצדפה באגן המזרחי של הים התיכון‪ .‬למרות זאת‪ ,‬ישנן עדויות המעידות על הידלדלותן באזור‬
‫הכרית‪ ,‬בעיקר בחגורת ה – ‪ ,Dendropoma‬בו היו נפוצות בעבר‪ .‬במהלך מחקר העוסק בדינמיקה של‬
‫אוכלוסיות הצדפה הפולשת הלפסית ‪ Spondylus spinosus‬לאורך חופי הארץ‪ ,‬נצפו קדיחות של ‪L.‬‬
‫‪ lithophaga‬בקשוות הצדפה‪ .‬בעקבות כך‪ ,‬בחנו בצורה כמותית את המצאות אוכלוסיית הצדפה הקודחת‬
‫במצע טבעי שבאזורים השונים של איזור המחקר ובקשוות של הצדפות הפולשות ‪ S. spondylus‬ו‪Chama -‬‬
‫‪ .pacifica‬על מנת לבחון את מצבה של הצדפה בחופי ישראל‪ ,‬איזור בו לא מתקיימת שלייה מסחרית‪ .‬המחקר‬
‫נערך בשנת ‪ 2010‬בעיקר בשונית שמול חוף קיבוץ שדות ים‪ ,‬אך גם במספר אתרים אחרים לאורך החוף‪.‬‬
‫במהלך העבודה נאספו דגימות סלע מחלקים שונים של אזור הכרית ושל אזור התת‪-‬כרית‪ ,‬כל דגימה נמדדה‬
‫(אורך ורוחב) ונשקלה‪ ,‬נספרו ונמדדו קדיחות ‪ L. lithophaga‬וכן כל פרטי ה‪ L. lithophaga -‬שנמצאו‬
‫בסלע‪ .‬במקביל‪ ,‬באופן דומה‪ ,‬נאספו הנתונים מקדיחות ‪ L. lithophaga‬שנצפו בקשוות של שתי הצדפות‬
‫המהגרות‪ .‬נמצא כי אוכלוסיות הצדפה הקודחת נפוצות בעיקר באזור התת כרית בצפיפות של עד ‪ 500‬פרטים‬
‫למטר מרובע בעיקר בסלעי גיר‪ .‬כמו כן‪ ,‬נמצא כי בשליש מאוכלוסיות שני מיני הצדפות הפולשות נמצאות‬
‫צדפות ה‪ .L. lithophaga -‬באזור הכרית כמעט ולא נמצאו קדיחות או צדפות‪.‬‬
‫מחקר זה מציג זו בפעם הראשונה נתונים כמותיים על אוכלוסיות הצדפה הקודחת בחופי הים התיכון של‬
‫ישראל ומראה כי בית גידולה העיקרי של האוכלוסייה הוא אמנם המצע הטבעי שבאזור התת כרית‪ ,‬אולם‬
‫קשוות הצדפות המהגרות מהוות גם כן מצע מוצלח ומתאים לקדיחה‪ .‬המחקר מראה כי אוכלוסיות הצדפה‬
‫הקודחת ‪ L. lithophaga‬מצויות באזור תת הכרית באגן המזרחי של הים התיכון בצפיפות הדומות לזו שבאגן‬
‫המערבי של הים התיכון‪ ,‬באזורים בהם לא נעשה איסוף מסיבי שלהן‪ .‬כמחקר המשך‪ ,‬מומלץ לבחון האם‬
‫קדיחת ‪ L. lithophaga‬ב‪ S. spinosus -‬מחלישה את הצדפה הפולשת ובכך יכולה להוות גורם ממתן של‬
‫הפלישה‪.‬‬
Precambrian natural injectors as a novel topical platform for systemic drug delivery
Esther Shaoul1, Ari Ayalon1, Yossi Tal1 and Tamar Lotan2
1
NanoCyte (Israel) Ltd, 38900 Caesarea, Israel
Marine Biology Department, The Leon H. Charney School of Marine Sciences,
University of Haifa, 31905 Haifa, Israel
2
Topically applied systems provide attractive solutions for local and systemic drug
delivery. However, only a limited number of drugs can be topically delivered through the
stratum corneum, the outer layer of the skin. The aquatic phylum Cnidaria, which
includes sea anemones, corals, jellyfish and hydra, is one of the most ancient
multicellular phyla equipped with a sophisticated injection system. The injection system
is folded within microcapsules and upon activation injects a thin tubule that immediately
penetrates the prey. Here we show that this natural microscopic injection system can be
adapted for transdermal drug delivery once it is isolated from the cells and uploaded with
the drug. Using a topically applied gel containing isolated natural sea anemone injectors
and the muscarinic receptor antagonist scopolamine, we found that the formulated
injectors could penetrate mammalian skin and achieve rapid systemic delivery of the
drug. The system was previously found to be both compatible with hydrophilic drugs and
clinically safe. Its additional advantages include high patient compliance, brief duration
of skin exposure to the drug and rapid drug delivery. The ability of isolated natural
injectors to penetrate a barrier as thick as the skin presents an intriguing alternative for
transdermal drug delivery.
Sustainable management of urban marine structures: results from the Adriatic Sea
and possible applications for Israeli coastlines
Perkol-Finkel Shimrit1, 2*, Rius Marc3, Fontana Giovanni1, Nicotera Valentina1, Franzitta
Giulio1, Ferrario Filippo1 and Airoldi Laura4
1
Centro Interdipartimentale di Ricerca per le Scienze Ambientali in Ravenna, University
of Bologna, Ravenna, Italy.
2
SeArc – Ecological Marine Consulting
3
Centre of Excellence for Invasion Biology, University of Cape Town, Cape Town,
South Africa.
4
Dipartimento di Biologia Evoluzionistica Sperimentale, University of Bologna,
Ravenna, Italy.
* [email protected]
With over 22,000 km2 of European coastlines covered by urban marine structures,
urbanization is one of the leading causes for habitat and species loss in coastal waters.
Marine infrastructures, often built on sandy bottom habitats, generate changes in species
composition, abundance and diversity. Understanding the factors controlling such
changes is crucial for proper management of coastal areas. Our research aimed at: 1)
analyzing the impact of coastal artificial structures on ecosystem functioning of benthic
infaunal communities, 2) developing means for promoting the growth of desirable species
and 3) determining the role coastal artificial structures in the establishment and spread of
invasive species. Following quantitative surveys along the 190 km of coastal defence
structures along the Italian North Adriatic Sea we conducted a an in-situ experiment
examining the impact of opportunistic species dominating the structures on adjacent softbottom communities. In addition we tested the feasibility of promoting the growth of
desirable native species on urban marine structures, using the canopy-forming alga
Cystoseira barbata as model species. Transplantation experiments demonstrated that
Cystoseira has the potential to grow on urban structures, but its success is influenced by
factors, including wave exposure and herbivorous pressure. Finally, we used extensive
surveys for determining whether urban structures facilitate the spread of invasive
tunicates. Not only did we found a greater proportion of NIS on marine infrastructures
than on nearby natural reefs, our results suggest that these structures also act as obstacles
for the natural pathways of dispersal of native populations. Advancing our understanding
of the impact of urban structures on marine habitats, and increasing our ability manage
their assemblages is of prime importance in light of the continuous proliferation of
coastal infrastructures. Possible applications for Israeli coastlines, paved with nearly 70
kilometres of coastal marine infrastructures, are presented.
Yacht tourism as a generator for economic development in small coastal
communities
Amir Shani and Nadav Shashar
Department of Hotel and Tourism Management, Ben-Gurion University of the Negev,
Eilat Campus, P.O. Box 653, Beer-Sheva 84105, Israel
Email: [email protected], Email: [email protected]
Niche tourism destinations and activities are often ignored in the tourism and economics
literature. Such destinations face fierce competitions from charismatic and well-founded
destinations, which are often backed with strong cultural, social and economic capacities,
as well as significant public relations. However, small coastal communities and islands
have the potential to gain competitive advantage by targeting specific market segments
that do not require high investment in infrastructure and hospitality amenities. Yacht
(small recreational boats) vacationers offer such a market while being a generator for
economic development for such communities. Examining the case of Greek northern
Dodecanese Islands in the Eastern Aegean Sea, we discuss the impacts of yacht charters
on coastal communities while stressing the contribution of such activities on local
entrepreneurships and the wellbeing of the local residents. It is concluded that niche
players such as small coastal destinations can successfully compete with well-resourced
destinations brands by focusing on special-interest tourists like yacht vacationers.
Managerial and marketing implications, as well as suggestions for future research, are
provided.
Response of Prochlorococcus ecotypes to co-culture with diverse marine bacteria
Daniel Sher
Department of Marine Biology, Leon H. Charney School of Marine Sciences, University
of Haifa, Mt. Carmel, 31905, Israel
Interactions between microorganisms shape microbial ecosystems. Systematic studies of
mixed microbes in co-culture have revealed widespread potential for growth inhibition
among marine heterotrophic bacteria, but similar synoptic studies have not been done
with autotroph/heterotroph pairs, nor have precise descriptions of the temporal evolution
of interactions been attempted in a high throughput system. Here, we describe patterns
in the outcome of pair-wise co-cultures between two ecologically distinct, yet closely
related, strains of the marine cyanobacterium Prochlorococcus and hundreds of
heterotrophic marine bacteria. Co-culture with the collection of heterotrophic strains
influenced the growth of Prochlorococcus strain MIT9313 much more than that of strain
MED4, reflected both in the number of different types of interactions and in the
magnitude of the effect of co-culture on various culture parameters. Enhancing
interactions, where the presence of heterotrophic bacteria caused Prochlorococcus to
grow faster and reach a higher final culture chlorophyll fluorescence , were much more
common than antagonistic ones, and for a selected number of cases were shown to be
mediated by diffusible compounds. In contrast, for one case at least, temporary inhibition
of Prochlorococcus MIT9313 appeared to require close cellular proximity. Bacterial
strains whose 16S gene sequences differed by 1-2% tended to have similar effects on
MIT9313, suggesting that the patterns of inhibition and enhancement in co-culture
observed here are due to phylogenetically-cohesive traits of these heterotrophs.
Decreased calcification of a coral reef flat in the Great Barrier Reef due to ocean
acidification
J. Silverman1*, K. Schneider1, D. I. Kline2, T. Rivlin3,4, A. Rivlin3, B. Lazar4, J. Erez4, K.
Caldeira1
1
Carnegie Institution, Department of Global Ecology, Stanford, CA, USA
Global Change Institute, Coral Reef Ecosystems Lab, The University of Queensland, St.
Lucia, Australia
3
The Interuniversity Institute for Marine Sciences, Eilat, The H. Steinitz Marine Biology
Laboratory, The Hebrew University of Jerusalem, Eilat, Israel
4
The Fredy and Nadine Herrman Institute of Earth Sciences, The Hebrew University of
Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel 91904
2
*Present address: Institute for Oceanographic and Limnological Research, Haifa, Israel
Ocean acidification is a major concern for coral reefs as declines in coral calcification
rates have already been documented in laboratory studies, and skeletal growth records
from across the Great Barrier Reef (GBR) show marked decreases in calcification over
the last two decades. During 2008-2009 we re-measured ocean chemistry and community
calcification on a reef flat in Lizard Island, GBR using the same methods employed at the
same site in 1975 during LIMER expedition. In 2008 and 2009 the community
calcification was lower by 42±10% compared to the rates measured in 1975. Our
measured community calcification decline is very close to the calculated decrease of
34±8% determined with our reef calcification rate law with carbonate chemistry and
temperature data from 1975 and 2008-2009. These findings provide the first direct
evidence for a substantial reduction in net CaCO3 precipitation of a coral reef caused by
ocean acidification.
Community calcification of the One Tree Island reef: a 40 year perspective
J. Silverman1*, K. Schneider1, D. I. Kline2, T. Rivlin3,4, L . Johnson5, B. Lazar4, J. Erez4,
K. Caldeira1
1
Carnegie Institution, Department of Global Ecology, Stanford, CA, USA
Global Change Institute, Coral Reef Ecosystems Lab, The University of Queensland, St.
Lucia, Australia
3
The Interuniversity Institute for Marine Sciences, Eilat, The H. Steinitz Marine Biology
Laboratory, The Hebrew University of Jerusalem, Eilat, Israel
4
The Freddy and Nadine Herrman Institute of Earth Sciences, The Hebrew University of
Jerusalem, Edmond J. Safra Campus, Jerusalem, Israel 91904
5
Department of Chemistry, Romberg Tiburon Center, San Francisco State University,
CA, USA
2
*Present address: Institute for Oceanographic and Limnological Research, Haifa, Israel
Throughout the 1960s and early 1970s pioneering studies in coral reef community
metabolism were conducted by Don and Barbara Kinsey on the One Tree island Reef
(OTR) and lagoon system. Since then ocean acidification and ocean warming have
become a major concern for coral reefs. In February and November-December 2009, we
conducted repeat measurements of community calcification in order to detect the effect
that ocean acidification may have had already on calcification rates in OTR. Using the
same methods developed by the Kinsey’s and sampling at the same site we found that the
net calcification of the reef had decreased by 26% in 2009 relative to the 1960s and 1970s
from 100 mmol m-2 day-1 to 75±17 mmol m-2 day-1 (±SE). During 2008-2009, the
daytime calcification rate was 337±12 mmol m-2 day-1 which is very similar to the rate
measured by the Kinsey’s, 320±13 mmol m-2 day-1. In contrast, during the nighttime
calcification measured in the present study was -163±11 mmol m-2 day-1, i.e. net
dissolution of CaCO3 and the rate measured by the Kinsey’s is -60±13 mmol m-2 day-1,
which is lower by a factor of 2.7. Interestingly the diel pH range reported by the Kinsey’s
for October 1968 was 8.10-8.43 (minimum nighttime-maximum daytime), while in the
current study the diel pH range for November-December was 7.66-8.56. These
differences suggest that the increase in nighttime dissolution may be associated with the
significant apparent respective pH decrease. The origin of this decrease is not clear and
while it could be associated with ocean acidification it may well be associated with
organic loading. In the latter case, increased organic loading may be supporting increased
biologically mediated dissolution of CaCO3. It is unclear what the source of the organic
loading may be and whether it can be related to global change processes, e.g. warming
and acidification.
Seasonal variability of oxygen and carbon stable isotopes, alkalinity and pH in the
Vermetid reef surrounding: Implications for the reconstruction of past
environments in the Eastern Mediterranean.
Guy Sisma-Ventura, Ruth Yam and Aldo Shemesh
Department of Environmental Sciences & Energy Research, Weizmann Institute of
Science, 76100 Rehovot, Israel; [email protected]
The Mediterranean Sea is a sensitive record of global and local climate changes due to its
location, the deficient hydrological balance and the high anthropogenic pressure.
Therefore, a great effort is invested in calibrating and applying new and reliable high
resolution proxies for this region. We attempt to calibrate the Eastern Mediterranean
vermetid reef δ18O and δ13C for paleo-environmental reconstruction by comparing highresolution measurements of the living vermetid skeletons and ambient seawater
properties. During the last two years, living reef tops and surface water from four coastal
stations and three open water stations (continental shelf) were sampled for δ18O, δ13C of
dissolved inorganic carbon (δ13CDIC), alkalinity (AT) and pH25°CTotal analysis. Our findings
show that both the reef surrounding and the shelf water have similar average δ18OSW of
1.6±0.12‰ and maintain low seasonal amplitude of 0.4‰ and positive correlation with
salinity. Similarly, the AT, ranging from 2597.6 - 2653.9 µmol/kg, closely reflect the
seasonal variability of salinity. The average reef surrounding δ13CDIC and pH25°CTotal of
1.04±0.28‰ and 8.05±0.04, respectively, show minor local variability, which results
with insignificant modification from the open water average of 0.9±0.13‰ and
8.02±0.02, respectively. Both, the reef surrounding and open water δ13CDIC lack clear
seasonal signal. The average living vermetid skeletal δ18O of 0.52±0.17‰ indicates
skeleton deposition mainly during summer and corresponds to average sea surface
temperature (SST) of 25.2±0.7°C. The vermetid δ18O captures the April-December mean
temperature and offsets from the SE-Mediterranean mean annual SST by ~2°C. The
depleted vermetid δ13C closely reflects the δ13CDIC of ambient seawater with almost
constant offset of 1.4±0.5‰, originated from metabolic carbon. Hence, we conclude that
vermetid δ18O and δ13C are reliable proxies for high-resolution reconstruction of
Mediterranean SST and δ13CDIC during the last millennium.
Modeling of Morphological Processes around Marine Facilities Located along the
Israeli Shore
Michael Sladkevich1, Eliezer Kit1,2, and Anna Levin1
1
Coastal and Marine Engineering Research Institute,
Technion City, Haifa, 32000, [email protected]
2
School of Mechanical Engineering, Faculty of Engineering,
Tel Aviv University, Tel Aviv, 69978, [email protected]
Mathematical modeling of morphodynamic phenomena represents one of the extremely
complicated and important problems in coastal engineering.
Construction of marine near-shore facilities makes obstacles for natural sand transport
patterns and brings about local seafloor as well as coastline changes. One of the
important things in mathematical modeling is a reliable representation of the sand bypass
along these facilities.
This work presents the modeling results of morphological changes in the vicinity of the
Marina Herzlya.
The analysis of bathymetric changes and coastline evolution in this region during the
period from 1987 to 1995 showed the following effects of the constructed stuctures on
the surroundings:
1. Three detached breakwaters located northward the Marina provided the beach
accumulation (formation of tombolos) in their sheltered zone.
2. Although the beach just downstream the Marine was preserved by the detached
breakwaters, an erosion of the seafloor as well as the shore was observed northward
these facilities.
3. The sand accumulation off the main breakwater.
4. The sedimentation was also observed in the Marina entrance and along the lee
breakwater.
5. Southward the Marine some coastline advance (smaller than expected) toward the sea
was noticed.
The model employed was Delft3D developed by the Delft Hydraulics.
The work performed demonstrates the ability of mathematical models to simulate natural
morphological phenomena in the coastal area in case when some marine facilities are
constructed.
In case of further construction of marine facilities along the Israeli shore, their impact on
the marine environment and, as a part of this, on sand transport, should be studied
beforehand as well as during their operation. In such a way adverse effects of human
activity in coastal area can be minimized.
The rhythmicity of photosynthesis in symbiodinium, the coral endosymbiotic algae.
Michal Sorek1,Yosef Yaacobi2 Modi Roopin1, Oren Levy1
1
2
Faculty of Life Science Bar Ilan University, Ramat Gan 52900. [email protected]
Kinneret Limnological Laboratory P.O.B. 447 Migdal 14950. [email protected]
Circadian clock is a biological mechanism conserved among a wide variety of organisms,
ranging from cyanobacteria to mammals, which governs daily rhythmicity of molecular,
physiological and behavioral process. The circadian clock is autonomous pacemaker that
can be entrained by environmental cues in order to preserve a 24-hour activity under
ambient light/dark cycles. Circadian clock in the plant kingdom has been known since the
18th century by the discovery that plants, which have been maintained under constant
conditions of light or darkness, still preserved rhythmic behavior, in spite of absence of
external stimuli. Since then, many circadian outputs were identified in plants to be
governed by the biological clock apparatus including cell elongation, carbon fixation, cell
division, metabolic pathways and photosynthesis.
Here we present for the first time that photosynthesis is governed by the endogenous
clock in the symbiotic coral Stylophora pistilata. As indication for photosynthesis
production we have monitored oxygen evolution using optic oxygen electrodes for
zooxanthellae cultures and by using in-situ respirometer for the endosymbiotic algae
found in the coral tissues. Imaging PAM and Fast Repetition Rate fluoroemeter (FRRf)
were used in order to measure quantum yield along with pigments concentrations using
HPLC. We successfully show that the circadian rhythm persisted for several days under
constant and manipulated light conditions in the symbiotic corals and in algae grown in
axenic culture. By using Fourier analysis we analyzed the duration of rhythmic
oscillations and found it to be 23.6 hrs, which is similar to other and higher lineages of
organisms. We further examined using QPCR the expression of two key genes in the
photosynthesis mechanism, D1 and chlorophyll ac binding under light dark cycle (LD)
and under constant light (LL) for a period of 48 hrs. The results presented are new in the
perspective of circadian clock in symbiotic organisms, which will further aim to inspect
and characterize the mechanism of this rhythm both physiologically and molecularly.
‫הדמיה ממוחשבת של האקולוגיה של אוכלוסיות פלנקטוניות במזרח האגן הלבנטיני‪.‬‬
‫יאיר סוארי ושלמה (סטיב) ברנר‬
‫המחלקה לגיאוגרפיה אוניברסיטת בר אילן‪ ,‬רמת גן ‪[email protected] ,52900‬‬
‫מזרח הים התיכון‪ ,‬בהיותו אולטרא‪-‬אוליגוטרופי ובעל יחסי חנקן לזרחן ייחודיים בכל הרמות של המערכת‬
‫הביוגיאוכימית מהווה איזור ייחודי מבחינת האקולוגיה הפלנקטונית וככזה מהווה אתר מתאים לבחינת‬
‫התפקוד של מודל אקולוגי ממוחשב‪ .‬כמו כן האיזור חשוף לשינויים אנתרופוגניים כמו סכירת הנילוס‪ ,‬פתיחת‬
‫תעלת סואץ והשפעות ההתחממות הגלובאלית‪ .‬מודלים ממוחשבים משמשים כלי מרכזי בבחינת השפעת‬
‫שינויים מסוג זה על האוקיאנוגרפיה הפיזיקלית ויהפכו כנראה לכלי כזה בבחינת ההשפעות על המערכת‬
‫האקולוגית‪.‬‬
‫במחקר זה אנו מדמים את הביוגיאוכימיה של האוכלוסיות הפלנקטוניות על ידי הרצה משולבת של המודל‬
‫הפיזיקלי ‪ Princeton Ocean Model‬והמודל הביוגיאוכימי ‪ .Biogeochemical Flux Model‬בשלב זה‬
‫מוצגות תוצאות של הרצות במימד אחד בהן המודל הפיזיקלי דימה את הפרופיל האנכי של הטמפרטורה‪,‬‬
‫המליחות והצפיפות ואת הערבול האנכי של המשתנים הביוגיאוכימיים והמודל האקולוגי דימה את התהליכים‬
‫האקולוגיים העיקריים‪ ,‬את עוצמת התאורה בעמודת המים ואת שקיעת החלקיקים‪ .‬המודל הפיזיקלי אותחל‬
‫ואולץ באמצעות שטפי חום ורוח ממוצעים רב שנתיים של נתונים יומיים כפי שהורכבו על ידי‬
‫‪ NCEP/NCAR‬והמליחות קובעה למליחות האקלימית מנתוני ‪ .MEDAR‬המודל האקולוגי אותחל‬
‫באמצעות נתונים מהספרות בנוגע למשתנים השונים ואולץ באמצעות שדה הקרינה קצרת הגל בפני השטח בו‬
‫השתמש המודל הפיזיקלי‪ .‬כיול המודל האקולוגי התבצע על ידי תהליך חוזר של הרצת המודל‪ ,‬בחינה‬
‫ויזואלית של התוצאות ושינוי הפרמטרים הקובעים את קצבי התהליכים בהתאם לקצבים מוכרים מהספרות‬
‫ולאי ההתאמות בין תוצאות המודל לתצפיות מהשטח‪.‬‬
‫המודל הצליח לדמות בצורה טובה יחסית את הדינמיקה העונתית של ריכוזי המשתנים הביוגיאוכימיים‪ ,‬את‬
‫תחומי הריכוזים ואת המבנה האנכי של עמודת המים‪ .‬אי ההתאמות העיקריות שראינו בין התצפיות לתוצאות‬
‫המודל היו בריכוזי ניטראט גבוהים יחסית בפני השטח ובמיקום רדוד מידי של שכבת מקסימום הכלורופיל‬
‫העמוק (‪.)DCM‬‬
‫תוצאות הכיול מוכיחות שניתן להשתמש במודל משולב תלת מימדי לבחינת ההשפעות של סכירת הנילוס ושל‬
‫ההזרמות מנחלי החוף על המערכת הפלנקטונית הימית‪.‬‬
Spatial distribution of Red Sea migrant fishes along the Eastern Mediterranean
Nir Stern and Menachem Goren
Department of Zoology, Tel Aviv University 69978, Israel, [email protected]
[email protected]
The constant rise of water temperatures along the Mediterranean Sea brings rapid
changes in fish diversity and distribution. Several Red Sea migrant fish had been already
established population as west as the Sicilian Strait, while the westernmost recordholders, Siganus luridus and Fistularia commersonii have recently reached the French
and the Algerian coasts, respectively.
Our research thoroughly investigated for the first time the quantitative relationships
between the indigenous and invasive fish species at the Eastern Mediterranean, in three
different sites. The research was conducted during 2008-2009 and was based on bottomtrawl catch in two fixed depths, 20m and 40m, from the coast of Ashdod, Israel, and from
Iskenderun Bay and Antalya Gulf, Turkey.
Turkish sampling sites comprised significantly heavier catch, mainly due to presence of
large indigenous Elasmobranchii species. By comparing spatial proportions for the
invasive species, the hypothesized decreasing east-west gradient was revealed: Ashdod
comprised 33% invasive species (50% of biomass), Iskenderun Bay with 25.2% invasive
species (30% of biomass) and Antalya Gulf with 21.5% (7.4% of biomass). Average
length analysis among eight of the most abundant species (four of which are veteran Red
Sea migrants) revealed significantly larger species at the Turkish sites. These results may
imply on exceptional environmental factors at the Israeli coast, e.g., low productivity and
higher water temperature, or on better fishery regulation at the Turkish coasts, which
provide the local ichthyofauna with better survival rates. A significant population growth
was seen in one of the recently invaded species, Nemipterus randalli. The number of
specimens increased from 2008 to 2009 samples in Ashdod, Iskenderun and Antalya
from 87,5,5 fish individuals to 879,773,49 individuals in 2009, respectively.
At present, this dynamic tropic fauna invasion is slowly turning the Levant Basin into a
branch of the Indo-Pacific Ocean. In the future, this may be the case with the rest of the
Mediterranean Sea.
Oxygen and coral evolution
Dan Tchernov, David Gruber and Tali Mass
Marine Biology Department,The Leon H.Charney School of Marine ciences, University
of Haifa, Mount Carmel, Haifa 31905.
The coral-algae endosymbiosis is considered a classical example of mutualism and is
credited with the evolution and propagation of tropical coral reefs .Determining the
geologic history of this relationship has been difficult due to incongruence in the coral
geologic record and dating from molecular clock methods. The evolutionary history of
this relationship is particularly important as it produced of the aragonite matrix that forms
the modern reef complex. This report synthesizes paleo-oxygen concentrations,
molecular phylogenics and coral physiology to provide a new insight into how this
relationship may have evolved.
‫משק המים וההתפלה בישראל‬
‫אברהם טנא‬
‫אגף ההתפלה‪ ,‬הרשות הממשלתית למים וביוב‪[email protected] ,‬‬
‫התפלת מי ים בישראל במתקני ענק החלה להתפתח בצורה מסיבית עם החלטות הממשלה משנת ‪ 2000‬ואילך‪.‬‬
‫ההרצאה תעסוק במדיניות ההתפלה ויישומה בטווח העשור הקרוב עם התייחסות לדורות הבאים‪.‬‬
‫כיום מתפילים כ‪ 330 -‬מלמק"ש ( מליון מ"ק לשנה) ‪ ,‬ובסוף שנת ‪ 2013‬נגיע להיקף התפלת מי ים של‬
‫כ‪ 600 -‬מלמק"ש ואולי אף יותר‪.‬‬
‫ההרצאה תציג את מטרת רשות המים וכיצד לממש אותה בעזרת ההתפלה‪.‬‬
‫יוצגו החלטות הממשלה בהקשר להיקפי ההתפלה‪.‬‬
‫יוצגו נתוני ההיצע והביקוש הצפויים לעשור הבא וכיצד נגזרת מהן תכנית ההתפלה ‪.‬‬
‫יתוארו טכנולוגיות ההתפלה המובילות ופירוט יתר לגבי הטכנולוגיה של אוסמוזה הפוכה שבשימוש בישראל‬
‫עם התייחסות לאיכות המים ומחירי ההתפלה‪.‬‬
‫תתואר צורת ההתקשרות של המדינה עם החברות המתפילות ומי הן החברות המובילות בתחום בישראל‪.‬‬
‫יתוארו החסמים השונים לקידום ההתפלה‪.‬‬
‫תינתן סקירה מקיפה של מתווה ההתפלה הנוכחי ויתוארו מתקני ההתפלה הקיימים והעתידיים‪.‬‬
Zooming into algal blooms- The chemical arms race in host-virus interactions in the
ocean
Assaf Vardi
Department of Plant Sciences, Weizmann Institute of Science, P.O. Box 26, Rehovot 76100
[email protected]
Marine viruses that infect phytoplankton blooms are recognized as a major ecological and
evolutionary driving force, shaping community structure and nutrient cycling in the
marine environment. Little is known about the signal transduction pathways mediating
viral infection and the role of cell signalling in such interactions.
We recently discovered that algal viruses posses the entire sphingolipid biosynthetic
pathway in their genome. These viruses completely modify the lipid profile of their algal
host and consequently exploit their host as a lipid factory. We show that viral
glycosphingolipids regulate infection of Emiliania huxleyi, a cosmopolitan
coccolithophore that plays a major role in the global carbon cycle. These sphingolipids
derive from an unprecedented cluster of biosynthetic genes in Coccolithovirus genomes,
are synthesized de novo during lytic infection, and are enriched in virion membranes.
Purified viral glycosphingolipids (vGSL) from infected E. huxleyi extracts induced
biochemical hallmarks of programmed cell death (PCD) in an uninfected host,
biomimicking viral infection. This induction provides a mechanistic framework for the
previously reported viral recruitment of host PCD machinery, which is essential for
successful infection. These novel vGSL were detected in coccolithophore populations in
the North Atlantic and in an induced E. huxleyi bloom in the Fjords of Bergen, Norway.
We currently lack biomarkers to quantify active viral infection in the oceans, which
significantly hindering our understanding of the role and activity of virus-mediated
processes in the oceans. Therefore, identification of our unique lipids can serve as novel
biomarkers for viral infection in the ocean. We further identified another distinct class of
lipids that were strongly induced during viral infection. Application of these purified
lipids prior to addition of viruses significantly prolonged host survival, suggesting a role
in host anti-viral chemical defense.
Our work underlines the co-evolution of host and virus around the PCD pathway and the
pivotal role of a chemical-based “arms race” to mediate and control these evolutionary
drivers in the marine environment.
A New Method for Precise Measurements of Dissolved Inorganic Carbon
Eyal Wurgaft, Eugeni Barkan, Boaz Lazar and Boaz Luz
The Fredy and Nadine Hermann Institute for Earth Science,
The Hebrew University of Jerusalem, Edmond J. Safra campus, Givat Ram
Jerusalem, 91904
Corresponding: [email protected]
Assessments of the inter-annual variations in oceanic dissolved inorganic carbon
(DIC) due to the increase in atmospheric CO2 are essential for accurate modeling of
the global CO2 cycle, and the oceanic CO2 cycle in particular. However, these
-1
-1
·y-1) relative to the existing DIC
·y-1). Therefore, a very precise DIC analysis is
required in order to study the short-term effect of the rise in atmospheric CO2 on the
oceanic carbon cycle.
The current precision of DIC determination is approximately 2 μmol·Kg-1, which is
suitable for measuring large seasonal variations in DIC. However, this precision is
clearly insufficient for assessing the annual variations in DIC associated with the
increase in atmospheric CO2. Here we describe a new analytical method for DIC
measurements that we developed for the purpose of measuring small variations in
DIC with the required precision.
The method is based on carbon isotope dilution, in which seawater samples are spiked
with a 13C enriched solution. The resulting 13C/12C ratios are measured by massspectrometry. The measured 13C/12C ratios are then used to calculate the seawater
DIC concentration. The analytical precision of our new method is currently better
than 0.7 μmol·Kg-1 and is expected to be improved even further.
The method has been tested both in laboratory and in the field. DIC profiles were
sampled in the Gulf of Aqaba, during the spring of 2010. The obtained results are in
good agreement with the expected characteristics of DIC during the sampling period,
thus supporting the validity of the method. The possible applications of this method
for the study of the oceanic CO2 cycle will be discussed.
‫הספינה טנטורה ‪ – E‬ממצאים‪ ,‬מחקר ושחזור‬
‫איל ישראלי‬
‫החוג לציוויליזציות ימיות‪ ,‬אוניברסיטת חיפה ‪[email protected]‬‬
‫שרידי הספינה טנטורה ‪ E‬אותרו במהלך סקר בלגונת דור בשנת ‪ .1995‬הספינה נחפרה שיטתית בשלוש‬
‫עונות חפירה בשנים ‪ 2007 ,2006‬ו ‪ 2008‬בידי משלחת מהמכון ללימודי ים על שם רקנאטי‪ .‬אתר הספינה‬
‫ממוקם בשוליה של תעלת השיט‪ ,‬בעומק מים ממוצע של ‪ 2.5‬מטרים‪ ,‬במרחק של ‪ 25‬מטרים מקו החוף וכיוונו‬
‫הכללי מצפון‪-‬מערב לדרום מזרח‪.‬‬
‫שרידי הספינה משתרעים על שטח שמידותיו ‪ 7.6‬על ‪ 3.1‬מטרים וכוללים‪ :‬חלקים ממערך השדרית― קורת‬
‫שדרית ישרה‪ ,‬מוט מקשר ו ‪ Gripe‬מעוגלים‪ ,‬שרידי מוט קצה ומקטע מתת השדרית‪ ,‬מערך צלעות‪ ,‬לוחות‬
‫גוף‪ ,‬חיזוק אורכי מרכזי‪ ,‬אורכנים ולוחות רצפה אשר עליהם אותרו אותיות חרותות‪ .‬בנוסף נמצאו שרידיה‬
‫של מחיצת רוחב אשר ככל הנראה הפרידה בין מטען הספינה לאזור אשר שימש את הצוות למחיה ואחסון‬
‫מטען אישי‪.‬‬
‫הספינה טנטורה ‪ E‬תוארכה באמצעות פחמן ‪ 14‬וממצא חרס לתקופה שבין המאות השביעית והתשיעית‬
‫לסה"נ‪ ,‬ראשית התקופה האיסלאמית בארץ ישראל‪ .‬מבנה הספינה תועד ושוחזר באמצעים ידניים וממוחשבים‬
‫המאפשרים הערכת מימדיה ושלבי בנייתה‪ .‬מערך הצלעות הצפוף‪ ,‬חיזוקי האורך המסיביים ולעומתם השימוש‬
‫בלוחות גוף קצרים וצרים שאינם מחוברים זה לזה‪ ,‬הם מאפיינים בולטים של בניה בשיטה של 'שלד קודם'‪.‬‬
‫לפיכך מהווה הספינה טנטורה ‪ E‬עדות לתהליך השינוי בשיטת הבניה מ'ציפוי קודם' ל'שלד קודם' באגן‬
‫המזרחי של הים התיכון‪.‬‬
Depth keeping by swimming against the flow in zooplankton: adaptive benefits and
ecological implications
Margarita Zarubin1,2, Viviana Farstey1, Dan Carlson1,3, Hezi Gildor3, and Amatzia
Genin1,2
1
The Interuniversity Institute of Marine Sciences, POB 469, Eilat 88103
Department of Evolution, Systematics and Ecology, The Hebrew University of
Jerusalem, Jerusalem 91904
3
Insititute of Earth Sciences, The Hebrew University of Jerusalem, Jerusalem 91904
2
Many zooplankters effectively maintain their depth by swimming against vertical
currents, thereby forming immense aggregations along oceanic fronts. The adaptive
benefit of this behavior, however, is unknown. Here we propose a link between depthkeeping, lipid content (density), and feeding biology in copepods. To generate effective
feeding currents, the difference between the density of the animal and the water around it
should be fixed (hereafter “dRo”), species-specific. Since copepods use lipids for storage
and the individual’s lipid content is a function of its recent feeding history, a large intraspecific variation in lipid content, hence in specific density, is expected. As water density
increases with depth, individuals of the same species that differ in their density are
expected to seek different depths. Indeed, our stratified sampling between 5 and 70 m
depth in the Gulf of Aqaba showed that in the copepods Ctenocalanus vanus and
Mecynocera clausi individuals having more lipids are found at greater depths.
Furthermore, because lipids are more compressible than water, individuals that do not
keep depth during downwelling (or upwelling) would reach depths where their dRo
would change only because of the change in pressure and temperature.
The effects of pressure, temperature and lipid content on the sinking velocity of the lipidrich copepod Rhincalanus nasutus were examined in a pressurized settling cylinder.
Although the results indicated strong lipid-dependent effects of temperature and pressure,
the effect of pressure was the opposite of expectations: high pressure (3.5 bars) slowed
down (rather than accelerated) the sinking velocity of individuals with high lipid content.
No pressure effect was observed for low-lipid individuals. While these results support our
hypothesis that lipid content and pressure affect the density of copepods, the nature of
this effect is not yet understood.
Preliminary CTD measurements during downwelling in the Northern Gulf of Aqaba
showed that an imaginary copepod that keeps its depth would experience a constant
temperature. In contrast, an imaginary copepod that is being downwelled would face a
slight temperature increase. This surprising result insinuates that there might be minute
changes in the micro-scale environment of copepods during downwelling events that
might lead to the enigmatic depth retention behavior. More measurements are currently
carried out to characterize downwelling events in more details.
Furthermore, we are currently designing an experiment to examine the effect of pressure
and temperature on copepod feeding rates. If such effects are observed, they will explain
not only the benefits of depth retention but also the factors based on which different
individuals (of the same species and life stage) select their foraging depths.
Excessive water level fluctuations enhance lake eutrophication
Tamar Zohary
Israel Oceanographic & Limnological Research, Kinneret Limnological Laboratory
[email protected]
Water levels of lakes and rivers fluctuate naturally in response to climatic and
hydrological forcing. Human over-exploitation of water resources leads to increased
annual and interannual fluctuations of water levels, at times far beyond natural
amplitudes. Climate change models predict increased occurrence of extreme events
(flooding; extended droughts), which will further magnify the seasonal and multi-annual
amplitude of water level fluctuations in lakes. A relatively wide literature base already
exists for shallow lakes, demonstrating that excessive water level fluctuations impair
ecosystem functioning, ultimately leading to shifts between clear-water and turbid states.
Evidence is gradually building up in the published literature to demonstrate that deep
(stratified) lakes also respond adversely to excessive water level fluctuations. At
moderate disturbance levels, littoral habitats and biota are impacted. At further
disturbance levels ecosystem destabilization symptoms are observed, including
weakening of keystone species, proliferation of nuisance and invasive species, loss of
biodiversity. Ultimately eutrophication symptoms are manifested without increased
external nutrient loading, especially cyanobacterial blooms. Examples from various
subtropical and temperate stratifying lakes and reservoirs demonstrate that both top-down
and bottom-up processes promote the development of those symptoms. The response of
aquatic ecosystems, and particularly of deep lakes, to water level fluctuations is an
understudied field, of crucial importance to the management of water resources, where
limnologists have a leading role to play in the near future.