Vegetation monitoring - Biodiversity Advisor

Transcription

Vegetation monitoring of the
herbaceous layer in THANDA
and
MDUNA:
2013
Noel van Rooyen
Gretel van Rooyen
10 June 2013
TABLE OF CONTENTS
EXECUTIVE SUMMARY .................................................................................................................................. i
TERMS OF REFERENCE .................................................................................................................................v
GENERAL INFORMATION ........................................................................................................................... vi
CHAPTER 1: INTRODUCTION .......................................................................................................................1
CHAPTER 2: PHYSICAL ENVIRONMENT ......................................................................................................3
CHAPTER 3: METHODS.................................................................................................................................9
CHAPTER 4: RESULTS ..................................................................................................................................18
BIBLIOGRAPHY AND REFERENCES............................................................................................................44
APPENDIX A: GPS COORDINATES OF SAMPLING PLOTS .......................................................................47
APPENDIX B: GRASS SPECIES AND ECOLOGICAL STATUS .....................................................................48
APPENDIX C: PHOTOGRAPHS OF 50 SAMPLING SITES ...........................................................................49
Thanda Mduna 2012
EXECUTIVE SUMMARY
Ekotrust CC has been appointed to establish a monitoring programme of the herbaceous
layer of Thanda Game Reserve and Mduna Royal Reserve. The aspects that were
addressed include the herbaceous vegetation, veld condition and grazing capacity.
Thanda Game Reserve and Mduna Royal Reserve are situated near Mkhuze in northern
KwaZulu-Natal. The GPS location of the main office in the northeast of Thanda Game
Reserve, is 27° 48’ 24.0” S and 32° 06’ 33.0” E. Thanda Game Reserve covers approximately
7130 ha and Mduna Royal Reserve 7566 ha for a total of 14696 ha. The terrain of Thanda
and Mduna Reserves ranges from plains in the east with hills, ridges and mountains in the
west with associated slopes, scarps and plateaux. The altitude ranges from 134 m on the
eastern boundary to 680 m on Bombolo Mountain in the west.
The mean annual rainfall ranges from about 580 mm at Mkhuze to as high as 1128 mm
against the escarpment at Hlabisa. The mean annual temperature for Mkhuze is 21.8°C
while the extreme maximum and minimum temperatures measured at Hlabisa were 44.5
and 3.3°C respectively. Frost is a rare occurrence in the area.
Thanda and Mduna are drained eastwards by a number of rivers such as the Mzunduzi,
Mduna, Ndlovini, Njakazane, Kwatateweni, Sivukana, Ndlovini and Ngweni Rivers. There
are currently about 10 earthen dams on Mduna, 6 earthen dams in Intibane (Bartenheim)
and more than 21 earthen dams spread over Thanda.
The geology of Thanda and Mduna consists of a number of substrates, i.e. basalt in the
east, and rhyolitic tuff, sandstone, shale, siltstone, mudstone and grit to the west. Narrow
quartz-porhyric dykes and dolerite intrusions, and alluvium along the rivers are spread over
the study area.
Phytogeographically, the area is contained in the transition zone from Zambezian
Woodland to Tongland-Pondoland bushland (White 1983). On the biome level, Thanda
falls in the Savanna Biome (Rutherford & Westfall 1986) and specifically the Lowveld
Bioregion (Mucina & Rutherford 2006). Mucina & Rutherford (2006) distinguishes the
Zululand Lowveld and Northern Zululand Sourveld in the study area.
The veld condition assessment is based on the method described by Bothma, Van Rooyen
& Van Rooyen (2004). The step-point method (100 points per sampling plot) was used to
determine the herbaceous plant species composition, species frequency, and ratio of
ecological status classes (class 1 to 5). The data are used to calculate the veld condition
index (%), which in turn may be used to estimate the ecological and economical grazing
capacity of Thanda and Mduna. The disc pasture meter (Trollope & Potgieter 1986,
Zambatis et al. 2006) was used to determine the grass production (fuel load) within most
vegetation types.
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The localities, GPS coordinates of plots 1 – 50 are given and the approximate positions of
the plots are indicated on the vegetation map of Thanda and Mduna. Monitoring of the
herbaceous layer was conducted in early April 2013 but should preferably be done in
March in future. Photographs were taken at the sites at the same time as the monitoring of
the grass layer was conducted.
The species composition, veld condition score and grazing capacity of the plant
communities monitored on Thanda and Mduna are discussed below:
1.
Acacia nigrescens – Acacia tortilis open bushveld and woodland
The community remained in an excellent condition in 2013, showing a slight increase in
veld condition index (88.3% in 2013 as against 84.0% in 2012). Grass canopy cover and
height (as indicated by the disc pasture meter) were fairly similar in the two years. Grazing
capacity increased from 43.5 GU / 100 ha in 2012 to 45.0 GU /100 ha in 2013.
2.
Acacia caffra – Diheteropogon amplectens wooded grassland and bushveld
Veld condition improved slightly in 2013 (83.1% in 2013 as against 77.0% in 2012), however,
the community remained in an excellent condition. Grass canopy cover and height (as
indicated by the disc pasture meter) were noticeably higher in 2013 than in 2012. Grazing
capacity increased from 33.7 GU / 100 ha in 2012 to 35.5 GU /100 ha in 2013.
3.
Ziziphus mucronata – Mundulea sericea bushveld and woodland
The veld condition index remained basically unchanged in the two years, with the
community in an excellent condition. Grass canopy cover and height (as indicated by the
disc pasture meter) were slightly higher in 2013 than in 2012. Grazing capacity remained
almost unchanged in 2012 compared to 2013.
4.
Combretum apiculatum – Aloe marlothii open bushveld and woodland
The veld was in excellent condition in both years with the grass canopy cover values also
similar. The settling height of the disc pasture meter was higher in 2013 than in 2012.
Grazing capacity in community 4 remained unchanged in 2012 compared to 2013.
5.
Acacia burkei – Panicum maximum open bushveld and woodland
The veld condition index was marginally higher in 2013, with the community in an excellent
condition in both years. Grass canopy cover was slightly higher in 2013 than in 2012,
whereas grass height (as indicated by the disc pasture meter) was noticeably higher in
2013 than in 2012. There was basically no difference in grazing capacity between 2012
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and 2013.
7.
Olea europaea – Berchemia zeyheri bushveld and thickets
The veld condition was notably higher in 2013 than in 2012 (index 84.1% as against 67.0,
and showed an improvement from moderate to excellent. Grass canopy cover was
however slightly lower in 2013 than in 2012. No disc pasture meter measurements were
taken in 2012. There was basically no difference in grazing capacity between 2012 and
2013.
8.
Olea europaea – Clerodendrum glabrum – Ehretia amoena dense bushveld and
thickets
Veld condition was notably higher in 2013 than in 2012 (index 77.7% in 2013 as against
48.0% in 2012, Table 25) and showed an improvement from poor to good/excellent. Grass
canopy cover showed an increase from 2012 to 2013, but grass height (as indicated by
the disc pature meter height) was similar. Grazing capacity increased from 32.4 GU / 100
ha in 2012 to 38.4 GU /100 ha in 2013.
11.
Acacia luederitzii thickets
Veld condition was notably higher in 2013 than in 2012 (index 72.7% in 2013 as against 56.0
in 2012) and showed an improvement from moderate to good/excellent. Grass canopy
cover and grass height (as indicated by the disc pature meter height) showed a marked
increase from 2012 to 2013. Grazing capacity increased notably from 31.1 GU / 100 ha in
2012 to 40.1 GU /100 ha in 2013.
12.
Acacia nilotica – Urochloa mosambicensis old fields and other disturbed areas
Veld condition was notably higher in 2013 than in 2012 (index 73.2% as against 46.0) and
showed an improvement from poor to good/excellent. Both grass canopy cover and grass
height (as indicated by the disc pature meter height) showed a marked increase from
2012 to 2013. Grazing capacity increased notably from 31.7 GU / 100 ha in 2012 to 45.9 GU
/100 ha in 2013.
Communities 9 & 10 were not monitored.
Biomass per community
Overall, there was a marked increase in herbaceous biomass in all the communities (with
the exception of community 8) in 2013 as compared to 2012. Highest biomass per
community in 2013 was recorded for community 5 and the lowest for community 12. In
2012 community 9 had the highest biomass.
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Grazing capacity
By comparison, the approximate economical capacities (ha/LAU) for Thanda and Mduna,
determined by different methods for 2013 are:
Estimate
Agricultural
Research
Council
estimates
(2007)(only grazers):
GU/BU method (Bothma et al. 2004) (grazers,
mixed feeders and browsers):
Veld condition/rainfall method (Danckwerts
1989)(only grazers):
Herbaceous phytomass method (Moore &
Odendaal 1987)(only grazers):
Rainfall/wildlife biomass method (Coe et al.
1976)(grazers, mixed feeders and browsers):
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Ecological
Economical
ha/LAU
ha/LAU
2012
2013
2012
2013
5-7
5-7
3.6
3.4
5.3
4.9
2.2
2.1
3.1
3.0
2.6
2.2
3.8
3.1
7.3
7.3
Thanda Mduna 2012
TERMS OF REFERENCE
The terms of reference for the 2013 baseline herbaceous vegetation monitoring surveys of
Thanda Game Reserve and Mduna Royal Reserve are to lay the foundation for a longterm vegetation monitoring programme and to initiate the baseline monitoring of the
herbaceous layer. Such a monitoring proramme should be able to follow trends in veld
condition, which in turn should be used to inform management on aspects such as
stocking densities, fire programmes and bush control.
The baseline monitoring project includes the following aspects:
•
Selection and surveys of suitable long-term monitoring sites for future reference
•
Proposal of methods with which monitoring should be done at each site.
•
Herbaceous layer surveys (species composition, dominance and biomass).
•
Fixed-point photographs.
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GENERAL INFORMATION
Ecologists compiling the report:
Dr Noel van Rooyen
Prof Gretel van Rooyen
Ekotrust CC
272 Thatchers Fields,
Lynnwood, 0081
Pretoria,
Tel/Fax 012 348 9043
Cell
082 882 0886
e-mail: [email protected]
www.ekotrust.co.za
Affiliation (N van Rooyen):
South African Council for Natural Scientific Professions) (Reg. no. 401430/83)
Southern African Institute of Ecologists and Environmental Scientists
(SAIE&ES)
Grassland Society of southern Africa (GSSA)
South African Wildlife Management Association (SAWMA)
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Thanda Mduna 2012
CHAPTER 1
INTRODUCTION
Ecological monitoring is defined as the purposeful and repeated examination of
appropriate biophysical parameters to determine the effects of particular management
strategies or policies, or the response of systems to changes in the environment. It is the
frequent testing of differences between baseline or initial surveys and follow-up surveys.
Ecological monitoring emphasizes changes in living organisms and not merely in the
physical environment (Hinds 1994).
Monitoring enables managers to periodically assess the state of the system so as to help in
decision making in the management process. It is therefore an important aspect of active
adaptive management strategies for conservation areas. A monitoring programme can
serve as an early warning system to detect changes or trends as a result of management
actions or natural events, with the goal to adapt management strategies where necessary.
It is now recognised that good management goes beyond implementation and that
effective management is integrally linked to well-designed monitoring or evaluation of
systems (Stem et al. 2005). Monitoring also allows managers to develop knowledge of their
particular ecosystems over time, which helps to predict how the system will respond to
various possible management alternatives (Pollock et al. 2002).
Therefore, when management decisions are implemented on a reserve, the possible
changes related to these actions should be monitored over time. For example, monitoring
is important whenever changes in the natural range are anticipated due to the release of
megaherbivores onto the reserve. The veld condition and grazing and browsing capacity
of all plant communities need to be monitored regularly when the number of animals
increases, because such increases could lead to overgrazing and changes in plant species
composition. Monitoring can also be applied to record the recovery of the vegetation in
those areas where past mismanagement occurred.
Monitoring methods need to be precise and easily measured in an objective and
repeatable manner (Bothma 2010). However, many scientific research methods are
expensive, and often require specialised skills or technology. To develop an ecological
monitoring programme for Thanda Game Reserve and Mduna Royal Reserve (hereafter
referred to as Thanda and Mduna), the monitoring methods have to be scientifically valid,
easily implemented and inexpensive to conduct. Furthermore, because reserve staff might
conduct future monitoring, the measuring techniques have to be fairly simple, but still
provide valid scientific data for analysis. Once the data are collected, reliably trained
managers or ecologists should be able to conduct the analysis. The monitoring methods
also have to be inexpensive regarding equipment and the duration of the monitoring
surveys should be manageable, as the monitoring budget is often limited.
A prerequisite in any monitoring programme is permanent baseline reference site,s which
are representative of what is considered necessary to be monitored. The size and shape of
the reference site will depend on the method adopted. The frequency of ecological
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monitoring depends on the rate of the ecological changes that are being measured, and
the size of the area.
Apart from the monitoring of the vegetation, some other aspects also need to be
monitored regularly to assist in the interpretation of the vegetation monitoring data. In a
natural environment there are a number of key components of the habitat and the animal
spectrum that give a reliable indication of how healthy the whole system is. Some aspects,
such as climate should be monitored continually, while the productivity of animals should
be monitored annually. Others may be measured over longer intervals. Some of the
aspects that need regular monitoring include the following:
1.
Climate: Rainfall needs to be measured routinely and the location of these rain
gauges should be within easy reach, e.g. at staff houses and lodges throughout the
area.
2.
Wildlife: Seasonal distribution, numbers of different types, population growth rate,
mortalities, herd composition (age and sex structure) and birth rates should be
monitored annually.
3.
Water provision: Location of permanent and artificial surface water, availability and
seasonality of water at different locations need to be recorded.
Soil erosion: Monitoring of erosion spread and the effects of habitat reclamation
4.
measures should preferably be updated annually.
The veld condition in terms of composition of the plant species, density and/or
cover, and plant biomass production should preferably be monitored annually.
Bush encroachment: Monitoring of control or spread could be monitored together
5.
6.
with the woody vegetation monitoring at three to five-year intervals.
Fire: Record location, date, weather conditions at time of burn, and fire intensity for
each event, and the surface area covered by a burn.
7.
8.
Woody vegetation composition, cover, density and browse production should be
monitored at 3-5-year intervals. This information should be used to calculate the
browsing capacity.
The objective of the annual monitoring of the herbaceous layer on Thanda and Mduna is
to gather information, which is essential:
•
to assess the herbaceous layer in terms of plant species composition, species
frequency and/or cover;
•
to determine the quality of the herbaceous layer and express it in terms of the veld
condition;
•
to calculate economic and ecological grazing capacity. This needs to be done
annually and the wildlife numbers adjusted accordingly;
•
to calculate the fuel load, which in turn is needed to plan a fire management
program; and
•
to evaluate the effects of rainfall, grazing pressure, watering points, erosion control,
bush encroachment control, or timing, frequency and intensity of fires.
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CHAPTER 2
PHYSICAL ENVIRONMENT
2.1
Location
Thanda Game Reserve and Mduna Royal Reserve are situated near Mkhuze in the Zululand
region of northern KwaZulu-Natal. The main office, in the northeast of Thanda Game
Reserve, is located at 27° 48’ 24.0” S and 32° 06’ 33.0” E. Thanda Game Reserve covers
approximately 7130 ha and Mduna Royal Reserve 7566 ha (Figure 1).
Figure 1.
2.2
The location of Thanda Game Reserve and Mduna Royal Reserve.
Topography and drainage
The terrain of Thanda ranges from plains in the east with hills and ridges and associated
slopes, scarps and plateaux in the west (Figures 1 & 2). The altitude ranges from 134 m on
the eastern boundary to 443 m above sea level on Mbedle in the central part of Thanda
(Figures 1 & 2). Mduna is more mountainous than Thanda and the altitude ranges from 180
m along the Msunduzi River in the north to 680 m at Bombolo Mountain on the western
boundary, a difference in elevation of 500 m.
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Thanda and Mduna are drained eastwards by a number of rivers such as the Mzunduzi,
Mduna, Ndlovini, Njakazane, Kwatateweni, Sivukana, Ndlovini and Ngweni Rivers. The rivers
are semi-perennial to seasonal, flowing mostly during the wet summer months, and are
sometimes reduced to isolated pools and subterranean seepage through bed sediments in
winter.
Figure 2.
2.3
Satellite image of the study area.
Climate
Rainfall
The climate of the region can best be described as warm to hot, humid, subtropical to
tropical with hot summers and cool to warm winters. Tropical cyclones occur infrequently
along the coast, generally from January to March, and are often accompanied by high
wind speeds. These tropical cyclones moving down the Mozambique Channel cause
episodic large-scale river floods.
The mean annual rainfall recorded at weather stations in the region ranges from about 580
mm at Mkhuze to as high as 1044 mm at St Lucia to the southeast near the coast, and up
to 1128 mm against the escarpment to the west at Hlabisa. In general, the highest rainfall
occurs from September to March, when more than 80% of the annual rainfall occurs, and
the lowest from June to July (Figure 3).
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Figure 3.
Mean rainfall and temperature curves for Thanda Game Reserve. Note that
the x-axis ranges from July to June (Mkhuze data)
Table 1
Mean monthly rainfall (mm) at a number of rainfall stations in the vicinity of
Thanda Game Reserve (Weather Bureau 1988, 1998)
Month
January
February
March
April
May
June
July
August
September
October
November
December
Year
Makatini
Mkhuze
Hlabisa
102
112
78
42
24
14
12
15
43
59
77
83
661
64
88
30
28
31
9
16
28
50
77
80
77
578
172
142
167
61
40
16
26
28
64
120
132
160
1128
St Lucia
Lake
153
125
124
87
60
42
41
49
69
87
114
93
1044
Mbazwana
133
140
108
76
47
40
42
40
50
83
90
86
935
Temperature
The mean annual temperature for Mkhuze is 21.8°C (Table 2) with the mean monthly
temperature for January 25.5°C and for July 16.4°C. The extreme maximum and minimum
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Thanda Mduna 2012
temperatures measured at Hlabisa were 40.6°C and 3.3°C respectively (Table 3). Frost is
therefore a rare occurrence in the area.
Table 2
Mean monthly temperature (ºC) for a number of weather stations in the
vicinity of Thanda Game Reserve
Month
Makatini
Mkhuze
Hlabisa
26.7
26.0
25.3
22.8
20.0
16.9
17.1
19.0
21.3
22.6
23.9
25.7
22.3
25.5
25.8
24.7
23.0
19.7
16.6
16.4
18.3
20.4
22.5
23.4
24.8
21.8
22.7
23.1
21.9
20.5
18.6
16.8
16.5
17.5
18.7
19.7
20.9
22.3
19.9
January
February
March
April
May
June
July
August
September
October
November
December
Year
Table 3
St Lucia
Lake
25.4
25.4
24.5
22.1
19.4
16.7
16.9
18.5
20.3
21.3
22.5
24.2
21.4
Ndumu
26.9
26.6
25.7
23.4
21.1
18.7
18.6
20.1
21.8
22.8
24.1
26.0
23.0
Extreme maximum and minimum temperatures recorded at a number of
weather stations in the vicinity of Thanda Game Reserve
Station
Makatini
St Lucia
Hlabisa
Ndumu
Maximum
Minimum
44.2
43.5
40.6
44.5
0.1
1.4
3.3
6.2
Wind, humidity, dew and evapotranspiration
Northeasterly and southwesterly winds predominate on the coastal plain, with the rainbearing winds coming from the southwest. Gale-force winds are most frequent from
September to December, and wind speeds of 26 to 40 km per hour and gusts of up to 140
km per hour have been recorded. Wind speeds greater than 50 km per hour occur on an
average of 12 days per year.
The air humidity is relatively high for most of the year. The monthly relative air humidity
ranges from 79% to 88% at 08:00 and from 68% to 74% at 14:00. The high relative air humidity
coupled with high summer temperatures result in a high discomfort index during the
summer months.
Dew is experienced throughout the year on calm, windless nights and is particularly heavy
during winter. The mean annual evaporation rate is approximately 1660 mm in the interior
region.
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2.4
Geology
The plains of Thanda are underlain by basalt. Narrow quartz-porhyric dykes and dolerite
intrusions, and alluvium along the rivers are spread over the study area. The substrates in
Mduna include rhyolitic tuff and perlite; and various types of sandstone, mudstone,
siltstone, shale and grit.
2.5
Land Types
Land Types denote areas that display a marked degree of uniformity with respect to terrain
form, soil pattern and climate. Thanda and Mduna falls in the Ea and Fb Land Types. The Ea
Land Type indicates land with red or dark coloured soils with a high base status, usually
clayey, more than half of which is covered by soil forms with vertic, melanic and red
structured diagnostic horizons. The basaltic low-lying plains, as well as the alluvial plains
along the Mzunduzi and Mduna Rivers fall within this land type.
The Fb Land Type covers the hilly country of Thanda and Mduna and refers to land where
lime is rare or absent in upland soils but is generally present in one or more valley bottom
soils. Lime has been used as an indicator of the extent to which these youthful landscapes
have been leached (low lime content indicates leached soils). This land type
accommodates pedologically young landscapes that are not predominantly rock and not
predominantly alluvial or aeolian, and in which the dominant soil forming processes have
been rock weathering, the formation of orthic topsoil horizons and, commonly, clay
illuviation, giving rise to lithocutanic horizons. The Glenrosa and/or Mispah soil forms are the
dominant soil forms in this landscape, indicating shallow soils on bedrock.
2.7
Vegetation
Most of the study area falls in the Zululand Lowveld (SVl 23) vegetation type (Mucina &
Rutherford 2006). This is an extensive flat or slightly undulating landscape supporting various
bushveld units ranging from dense thickets of Dichrostachys cinerea and Acacia species,
through park-like savanna with Acacia tortilis to tree-dominated woodland characterised
by Acacia nigrescens and Sclerocarya birrea. Tall grassland with scatterred trees forms a
mosaic with the savanna thornveld, bushveld and thickets.
The tall trees include Acacia nigrescens and Sclerocarya birrea, while the tree layer is
characterised by Acacia nilotica, Acacia tortilis, Acacia gerrardii, Combretum apiculatum,
Combretum molle, Spirostachys africana, Schotia brachypetala, Ziziphus mucronata,
Boscia albitrunca and Olea europaea subsp. africana. The shrub layer is characterised by
Dichrostachys cinerea, Euclea schimperi, Euclea divinorum, Euclea crispa, Gymnosporia
maranguensis and Gymnosporia senegalensis. Succulent trees include Euphorbia ingens,
Euphorbia grandidens and Aloe marlothii. The forb layer is represented by Barleria obtusa,
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Pavonia columella, Crossandra greenstockii, Justicia flava, Melhania didyma, Ruellia
cordata, Acrotome hispida, Helichrysum rugulosum and Felicia muricata. The most
prominent grass species include Themeda triandra, Panicum maximum, Eragrostis curvula,
Eragrostis racemosa, Heteropogon contortus, Bothriochloa insculpta, Tristachya leucothrix,
Aristida congesta and Setaria incrassata.
The southeastern high-lying parts of Mduna were mapped as Northern Zululand Sourveld
(SVl 22) by Mucina and Rutherford (2006). However, the vegetation in Mduna is not typical
of this vegetation type. The terrain in the Northern Zululand Sourveld is generally undulating
and sometimes highly dissected by low mountains. The Glenrosa and Mispah soil forms are
dominant and the soils are derived from diamictites, shale, siltstone, sandstone and granite.
The most important tree species are Acacia sieberiana, Acacia natalitia and Acacia
tortilis. Prominent shrubs include Plectroniella armata and Gardenia volkensii. The dominant
grass species include Eragrostis curvula, Hyparrhenia hirta, Microchloa caffra, Themeda
triandra and Tristachya leucothrix. Dwarf shrubs and forbs include Crossandra greenstockii,
Alepidea longifolia, Berkheya speciosa, Crabbea hirsuta, Gerbera ambigua and
Hilliardiella oligocephala.
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CHAPTER 3
METHODS
3.1
Step-point method
The step-point method (Mentis 1981) is based on the wheel-point method developed by
Tidmarsh & Havenga (1955) and was used to determine the herbaceous plant species
composition, species frequency, and ratio of ecological status classes (class 1 to 5). The
data are used to calculate the veld condition index (%), which in turn may be used to
estimate the ecological and economical grazing capacity of Thanda and Mduna. One
hundred points were done per sampling site and at each point the nearest plant species
(forb or grass species) was recorded. All non-grassy herbs were recorded as forbs and were
therefore not identified and recorded at species level. The reasons for this decision being
threefold:
•
because of the relatively high rainfall of the region and the generally high grass
cover in most areas, forbs have a relatively low presence in the area;
•
the additional time it would take to identify these to species level; and
•
the fact that all forbs are classified as Class 5.
The annual and perennial grass species were not recorded separately because of the
relatively low contribution annual grasses make to the overall composition and biomass
between years. If no plants are found within a 0.5 m radius from the point, it is recorded as
bare soil.
Frequency (%)
=
Number of nearest recordings of a species
x 100
Total number of points
3.2
Veld condition assessment
The approach followed is based on the method described by Bothma, Van Rooyen & Van
Rooyen (2004). The first step is to determine the plant species composition and degree of
dominance of the grasses and forbs in a community. The grasses and forbs are subjectively
classified into five ecological classes, based on their perceived grazing value, biomass
production and palatability (see Appendix B). The five ecological classes (and their
constant multiplier in terms of ecological value as forage) that are recognized are the
following:
Class 1:
Valuable and palatable tufted and stoloniferous grass species with a high
productivity and high grazing value (multiplier for veld condition x10)
Class 2:
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Tufted grass species with an intermediate productivity and moderate
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Thanda Mduna 2012
grazing value (multiplier for veld condition x7)
Class 3:
Tufted grass species with a high productivity but a low grazing value
(multiplier for veld condition x5)
Class 4:
Generally unpalatable and perennial tufted and stoloniferous grass species
with an intermediate productivity and a low grazing value (multiplier for veld
condition x4)
Class 5:
Unpalatable annual grass and forb species with a low productivity and low
grazing value (multiplier for veld condition x1).
By using these classes, an ecological score is calculated to express veld condition.
Theoretically, the maximum ecological score value that can be obtained is 1000, i.e. if all
species present are classified as Class 1 species.
The veld condition score is usually
expressed as a percentage and indicated as the veld condition index. A veld condition
index lower than 50%, usually reflects a low grass cover, high percentages forbs and
unpalatable annual grasses, low biomass production and consequently indicates veld in
poor condition for grazers. Veld in good to excellent condition should have an index of
higher than 70%, with a high grass cover and a high presence of perennial Class 1, Class 2,
and some Class 3 species.
3.3
Grazing capacity
The calculation of an approximate grazing capacity for each vegetation unit was based
on the method described by Bothma, Van Rooyen & Van Rooyen (2004). Other methods
to determine the grazing capacity were also used for comparison such as the Veld
Condition/Rainfall method (Danckwerts 1989), the Herbaceous Phytomass Method (Moore
& Odendaal 1987), and the Rainfall/Wildlife biomass method (Coe et al. 1976).
The following basic definitions and principles have been applied in the determination of
the grazing capacity of the reserves:
3.3.1
Stocking density:
The stocking density is the number of wild herbivores of various types that are kept on a
given unit of land surface. The stocking density depends on a management decision that is
based on the objectives for the reserve, but it must be within the ecological capacity of
the habitat to support grazing and browsing herbivores. Low stocking densities relative to
the ecological capacity of the habitat are aimed at the maximum meat production per
animal unit (kg per animal), whereas high stocking densities are aimed at the maximum
meat production per unit area (kg per ha).
3.3.2
Grazing capacity:
In the current agricultural usage in South Africa, grazing capacity is the area of land that is
required to maintain a Large Animal Unit (LAU) in order to achieve maximum profit in the
short term, while maintaining the condition of the vegetation and soil in such a way as to
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Thanda Mduna 2012
be able to fulfil the needs and aspirations of future land users. Defined in this way, grazing
capacity is either expressed as ha per Large Animal Unit, or as Large Animal Units per ha.
For wildlife, grazers and browsers are separated and the grazing and browsing capacity
are expressed in terms of Grazer Units (GU) per 100 ha and Browser Units (BU) per 100 ha
(see 3.3.4).
3.3.3
Grazing capacity for wildlife:
This concept reflects the ecological production potential of the grazeable portion of a
homogeneous unit of vegetation, and represents the area of land (ha) that is required to
maintain a single Grazer Unit (GU) over an extended number of years without deterioration
of the vegetation or the soil. A blue wildebeest Connochaetes taurinus taurinus with a mass
of 180 kg is taken as being equivalent to a Grazer Unit. The grazing capacity for wildlife is
expressed as the number of Grazer Units per 100 ha.
3.3.4
Browsing capacity for wildlife:
This concept reflects the ecological production potential of the browseable portion of a
homogeneous unit of vegetation and is expressed as the area of land (ha) that is required
to maintain a single Browser Unit (BU) over an extended number of years without
deterioration of the vegetation or the soil. A greater kudu Tragelaphus strepsiceros of 180
kg is taken as being equivalent to a Browser Unit. The browsing capacity for wildlife is
expressed as the number of Browser Units per 100 ha.
3.3.5
Economical and ecological capacity:
When wildlife are introduced to an area, their numbers will increase from an initial low to a
level where social behaviour and resources such as available food, water and shelter
become limiting. Numbers increase slowly at first and once a critical stage is reached, the
growth rate at first becomes exponential and the population size increases rapidly. At a
certain upper level, density-dependent factors such as competition for resources sets in
and lower fecundity and increased mortalities result in a leveling-off of population growth
to a point where births equal deaths, and net growth (or yield) is zero (S-curve). In practice,
the ultimate population density fluctuates around an upper level, which arises from, for
example, variations in rainfall, interspecific competition, predator-prey relations or
accidental fires. The level around which the population oscillates is known as the
ecological capacity. Fluctuations in numbers can be quite dramatic, with severe crashes
occurring during catastrophes such as periods of prolonged drought or disease epidemics.
Allowing certain gregarious wildlife to attain high densities may impact negatively on other
more sensitive ones. Therefore, should the management objective be to increase wildlife
diversity, the numbers of aggressively competitive wildlife, such as blue wildebeest and
Burchell’s zebra, have to be controlled. If a population is being maintained below the
ecological capacity by cropping or capture, the net growth of the population is positive,
as there is room for expansion in the form of resource abundance. The population is then
held at an economical capacity, implying that this capacity is efficient in ensuring a
positive growth rate. For optimum wildlife production the economical capacity is usually
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Thanda Mduna 2012
set at 70% of the ecological capacity.
In combination, the grazing and browsing capacity form the ecological capacity of the
vegetation (habitat) to support large herbivores. In essence the ecological capacity for
herbivores of a habitat is the maximum number of grazers and browsers that a given area
of land can sustain based on the biophysical resources of the area at a given time.
Depending on the management objectives, the economical grazing and browsing
capacities can be adjusted, provided that it remains within the limits set by the ecological
capacity of the area for herbivores.
By using the ecological index, the total grass canopy cover, mean annual rainfall, fire
regime and accessibility of the area, and the social behaviour of the wildlife, an ecological
and economical grazing capacity can then be calculated for each plant community.
Apart from the different classes of the herbaceous vegetation (grasses and forbs), the
impact of dense woody layers as well as steep and rocky slopes has an influence on the
grazing capacity of each community. These grazing capacity values, weighted by the
surface area covered by each community, were added to derive the ecological and
economical stocking densities for Thanda and Mduna. The grazing capacities of the plant
communities on Thanda and Mduna were calculated for wildlife at a mean annual rainfall
of 845 mm.
3.4
Biomass production
The disc pasture meter (Trollope & Potgieter 1986, Zambatis et al. 2006) is a suitable
apparatus to determine the grass production (fuel load) within most vegetation types. It is
regarded as a rapid, non-destructive method to determine dry mass yield of grassland. At
each monitoring site 50 readings (disc height in centimetre) were recorded to calculate a
mean settling height of the disc.
The disc pasture meter ideally has to be calibrated for the area under study. Trollope &
Potgieter (1986) described the method of calibration through the use of regressions,
comparing the actual dry mass of the plant material to the square root of the disc pasture
meter’s readings. The equation of Trollope & Potgieter (1986) was re-evaluated by
Zambatis et al. (2006) and two equations were proposed, one for a mean disc height of
≤26 cm and one for a mean disc height of >26 cm. Until a calibration and an equation
have been produced for Thanda and Mduna, the following equations of Zambatis et al.
(2006) were used to determine the grass biomass (kg/ha):
Equation 1 for a disc height of ≤26 cm:
kg.ha-1 = [31.7176(0.32181/x)x0.2834]2
where:
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x = mean disc height in cm of a site
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Thanda Mduna 2012
Equation 2 for a disc height of >26 cm:
kg.ha-1 = [17.3543(0.9893x)x0.5413]2
where:
4.
x = mean disc height in cm of a site
Fixed-point photography
This is an essential component of monitoring. By taking photographs of the vegetation or
landscape from the same point at regular intervals and at the same time of year, a visual
record is obtained which could at a later stage be subjected to objective analysis (Joubert
1983). The advantages derived from fixed-point photographs include the following:
1
They provide a rapid means for assessing short and medium term trends in the
vegetation, and therefore can have predictive value.
2.
They provide additional evidence for evaluating and interpreting the impact of
various external influences on the vegetation.
3.
The method is cheap, easy to apply and provides a permanent record for reexamination when required.
The disadvantage of the method is that it is difficult to quantify the results and therefore not
readily subject to statistical analysis. However, improvements in computer software have
facilitated the analysis and comparison between photographs. During this survey, one
photograph was taken at each sampling plot (Appendix C).
Photographs should also be taken at the same sites towards the end of winter, e.g. in
August, to enable visual comparisons of seasonal changes in the volume of grass material
and also to estimate the proportion of evergreen : deciduous trees.
5.
Location of monitoring sites
The localities, GPS coordinates of plots 1 – 50 are given in Appendix A. The approximate
positions of the plots are indicated on the vegetation map of Thanda and Mduna (Figure
4). Overall, fewer sampling sites were selected for the thicket communities because these
generally have a poorly developed grass layer.
The selected monitoring plots have been numbered from 1 – 50. For comparative purposes
the plot numbers of the Braun-Blanquet classification survey have been included in the
tables (Van Rooyen & Van Rooyen 2012).
The 50 monitoring plots cover the dominant plant communities (Table 4, Figure 4; Van
Rooyen & Van Rooyen 2012). These communities cover almost 81% of the total area of
Thanda and Mduna. The communities not sampled are:
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Thanda Mduna 2012
•
Community 6, the Olea capensis – Mystroxylon aethiopicum ridge bushveld, which
covers only 0.5% of the area of the reserve. The herbaceous vegetation in this
community on the ridges is generally sparse.
•
Community 9, the Acacia xanthophloa – Spirostachys africana riparian vegetation,
which covers 14.7% of the reserve. This community comprises two subcommunities:
The open woodland and forests cover approximately 1609 ha (about 11% of the
Reserve) and occurs on the eastern lowland floodplains and streambanks; whereas
the dense riparian subcommunity covers approximately 548 ha (about 3.7% of the
Reserve) and occurs along the drainage lines. Herbaceous cover in the latter
subcommunity is generally sparse due to the dense cover of woody plants.
•
Community 10, the Euphorbia tirucalli – Ficus abutilifolia ridge bushveld, which
covers only 1.6% of the reserve. The herbaceous vegetation in this community on
the ridges is generally sparse.
6.
Time of monitoring
Monitoring of the herbaceous layer was conducted in early April 2013. Monitoring should
preferably be done in March in future.
Photographs were taken at the sites at the same time as the monitoring of the grass layer
was conducted. It is suggested that photographs should also be taken at the same sites
towards the dry period at the end of winter/early spring.
7.
Data analysis
Mean values for the frequency of each species, frequency of classes, veld condition score,
veld condition index, grass cover and mean disc settling height, were calculated for every
community. The mean values were used to calculate the biomass and grazing capacity for
each community.
In the following text comparisons are provided with the 2012 surveys. However, the data for
2012 consisted of more plots per community because all the surveys used for the
vegetation classification were considered and not only those plots selected for monitoring
purposes.
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14
Thanda Mduna 2012
Table 4.
The monitoring plots, the plant communities they represent and the area (%)
of reserve covered by the each community
Community Community name
Monitoring plot no
Area
(plot number of 2012
covered by
vegetation survey in
community
brackets)
(%)
Acacia tortilis – Acacia nigrescens open
1 (1), 2 (2), 3 (8), 4 (9),
17.3
bushveld and woodlands
5 (27), 6 (54), 7 (57), 8
no
1
(new)
2
3
Acacia caffra – Diheteropogon amplectens
9 (29), 10 (34), 11 (41),
wooded grassland and bushveld
12 (88)
3.9
Ziziphus mucronata – Mundulea sericea
13 (49), 14 (60), 15 (67), 5.1
bushveld and woodland
16 (79), 17 (80), 18 (84),
19 (100)
4
Combretum apiculatum – Aloe marlothii open
20 (33), 21 (36), 22 (38), 12.2
23 (39), 24 (40), 25 (45),
26 (64), 27 (70), 28 (73),
29 (new)
5
6
Acacia burkei – Panicum maximum open
30 (26), 31 (48), 32 (75), 12.4
33 (94), 34 (97)
Olea capensis – Mystroxylon aethiopicum ridge Not sampled
0.5
bushveld
7
8
Olea europaea – Berchemia zeyheri bushveld
35 (78), 36 (85), 37 (90), 7.0
and thickets
38 (91), 39 (92)
Olea europaea – Clerodendrum glabrum –
40 (4), 41 (76)
11.2
Not sampled
14.7
Not sampled
1.6
Ehretia amoena dense bushveld and thickets
9
Acacia xanthophloa – Spirostachys africana
riparian vegetation
10
Euphorbia tirucalli – Ficus abutilifolia ridge
bushveld
11
42 (14), 43 (15), 44 (22), 11.3
45 (23), 46 (68), 47 (69)
12
Acacia nilotica – Urochloa mosambicensis old
48 (11), 49 (18), 50 (19)
2.6
fields and other disturbed areas
Habitation
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0.3
15
Thanda Mduna 2012
Figure 4.
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Vegetation map of Thanda and Mduna with approximate localities of 50 monitoring plots.
16
Thanda Mduna 2012
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17
Thanda Mduna 2012
CHAPTER 4
RESULTS
4.1
Introduction
Veld condition, biomass and consequently the grazing capacity of any area, will generally
vary annually and seasonally. Annual variation depends mainly on the rainfall and to a
certain extent on grazing pressure, especially when the grass phytomass is used to
determine grazing capacity.
4.2
Veld condition and grazing capacity per community
A veld condition index lower than 50%, reflects a low grass cover, many unpalatable annual
grasses and forbs (Class 5), low biomass production and bare soil, and consequently
indicates veld that is in poor condition for grazers. Veld that is in moderate condition has an
index of 50 – 70%, while veld in good to excellent condition has a veld condition index of
higher than 70%, with a high grass cover and a high presence of perennial Class 1 and Class
2 species.
The species composition, veld condition score and grazing capacity of the plant
communities monitored on Thanda and Mduna are discussed below:
1.
Acacia nigrescens – Acacia tortilis open bushveld and woodland
This community is divided into two subcommunities and is located on plains, footslopes,
midslopes and low hilltops in the eastern and central parts of Thanda. Veld condition
assessments in 2013 were done for the community as a whole and were not separated by
subcommunity. Density and cover values for the woody strata were not assessed during the
monitoring of the herbaceous layer in 2013. The density and cover of woody species
estimates made during the 2012 vegetation survey are provided in Table 5 for descriptive
purposes.
Table 5.
Density and cover of woody strata in community 1 as established during field
surveys in 2012
Subcommunity
Individuals per ha
Canopy cover (%)
1a
1b
1a
1b
Mean
Canopy
cover (%)
6
Tall trees (>6 m)
13
75
2
10
Trees (3 - 6 m)
88
123
7
10
9
Shrubs (<3 m)
704
723
10
12
11
Shrubs minimum
388
388
Shrubs maximum
1100
1625
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Thanda Mduna 2012
Table 6.
Frequency of species, classes and veld condition index, grass cover and disc
pasture meter height for eight plots monitored in community 1 in 2013
Monitoring plot no
Vegetation classification plot no
Aristida adscensionis
Aristida bipartita
Bothriochloa insculpta
Cenchrus ciliaris
Chloris virgata
Digitaria eriantha
Eragrostis cilianensis
Eragrostis curvula
Eragrostis lehmanniana
Eragrostis sp.
Eragrostis superba
Eustachys paspaloides
Forbs
Heteropogon contortus
Ischaemum afrum
Leptochloa eleusine
Panicum deustum
Panicum maximum
Setaria incrassata
Setaria sphacelata
Sporobolus ioclados
Themeda triandra
Urochloa mosambicensis
Total
1
1
1
0
3
1
0
0
0
0
0
0
1
0
2
2
1
2
16
32
1
0
1
32
5
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
1
1
81
6
3
4
6
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Veld condition score
Veld condition index
Grass cover (%)
Disc pasture meter height (cm)
1
1
810
42
15
16
6
889
88.9
92
21.4
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2
2
1
0
0
0
0
2
0
0
0
0
0
0
3
0
0
1
5
69
0
0
0
19
0
100
Frequency of occurrence (%) of species
3
4
5
6
7
8
8
9
27
54
57 New
0
0
1
0
0
2
3
0
0
0
0
0
0
0
17
0
0
0
0
0
8
0
0
0
0
0
1
2
0
1
4
0
1
0
2
0
0
0
0
1
0
0
2
0
0
0
0
0
1
0
0
0
0
0
6
0
0
0
0
0
0
0
6
0
0
0
3
0
0
0
0
0
0
0
10
3
4
5
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
6
6
18
0
1
14
0
0
45
38
80
28
86
34
0
0
0
0
0
0
0
0
0
25
0
0
0
2
0
0
0
41
37
6
12
27
0
0
0
10
0
0
0
100
100
100
100
100
100
2
2
95
0
1
0
4
100
Frequency of occurrence (%) of classes
3
4
5
6
7
8
8
9
27
54
57 New
51
100
53
93
71
86
39
0
10
0
25
0
1
0
0
1
0
6
6
0
9
2
0
1
3
0
28
4
4
7
100
100
100
100
100
100
Mean
0.6
0.4
2.5
1.1
0.5
1.1
0.1
0.3
0.1
0.8
0.9
0.4
3.4
0.3
0.1
1.3
7.5
47.3
4.4
3.1
0.4
21.8
1.9
100.0
Mean
78.7
10.0
1.5
2.8
7.0
100.0
Frequency of occurrence (%) of classes X class multiplier
2
3
4
5
6
7
8
Mean
2
8
9
27
54
57 New
950
510 1000
530
930
710
860
787.5
0
273
0
70
0
175
0
70.0
5
5
0
0
5
0
30
7.5
0
24
0
36
8
0
4
11.0
4
3
0
28
4
4
7
7.0
959
815 1000
664
947
889
901
883.0
95.9
81.5
100
66.4
94.7
88.9
90.1
88.3
90
90
95
80
90
90
95
90.3
21.2
10.5
20.0
10.5
19.0
27.7
18.0
18.5
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Thanda Mduna 2012
Table 7.
Comparison between 2012 and 2013 of various monitored parameters in
community 1
Grass layer canopy cover (%)
Community 1
2012
2013
87
90
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
75.5
5.5
2.5
5.0
11.5
0.0
78.7
10.0
1.5
2.8
7.0
0.0
Veld condition index (%)
83.8
88.3
Grazer units per 100 ha
Disc pasture meter settling height (cm)
Biomass (kg/ha)
43.6
16.5
4059
45.0
18.5
4652
The community remained in an excellent condition in 2013, showing a slight increase in veld
condition index (Table 7, 88.3% in 2013 as against 84.0% in 2012). Class 1 species, notably
Panicum maximum and/or Themeda triandra, dominated at all sample plots. The frequency
of Panicum maximum showed a noticeable increase from 29.4% in 2013 to 47.3% in 2013,
whereas the frequency of Digitaria eriantha declined from 9.7% in 2012 to 1.1% in 2013. Grass
canopy cover and height (as indicated by the disc pasture meter) were fairly similar in the
two years.
Grazing capacity increased from 43.5 GU / 100 ha in 2012 to 45.0 GU /100 ha in 2013.
2.
Acacia caffra – Diheteropogon amplectens wooded grassland and bushveld
This community occurs on west-facing midslopes and low hilltops in Thanda and Mduna. The
southwest and west-facing slopes are from 4 - 25º in gradient. Density and cover estimates
for the woody strata made during the 2012 vegetation survey are provided in Table 8.
Almost no tall trees were recorded in the community, although shrubs were common.
Table 8.
surveys in 2012
Plant community
Individuals per ha
Canopy cover (%)
Tall trees (>6 m)
2
2
Trees (3 - 6 m)
75
8
Shrubs (<3 m)
538
14
Shrubs minimum
275
Shrubs maximum
800
Themeda triandra, Panicum deustum and Panicum maximum, all three Class 1 species, had
the highest frequencies in 2013 (Table 9). Diheteropogon amplectens showed a marked
increase in 2013, whereas Digitaria eriantha showed a decline. Veld condition improved
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Thanda Mduna 2012
slightly in 2013 (Table 10, 83.1% in 2013 as against 77.0% in 2012), however, the community
remained in an excellent condition. Grass canopy cover and height (as indicated by the
disc pasture meter) were noticeably higher in 2013 than in 2012.
Table 9.
pasture meter height for four plots monitored in community 2 in 2013
Monitoring plot no
Chloris virgata
Cymbopogon caesius
Digitaria eriantha
Diheteropogon amplectens
Eragrostis superba
Forbs
Panicum deustum
Panicum maximum
Setaria sphacelata
Sporobolus ioclados
Themeda triandra
Trachypogon spicatus
Total
9
10
11
12
Mean
29
34
41
88
1
0
0
0
0.3
0
0
8
22
7.5
0
2
0
0
0.5
0
6
19
20
11.3
0
1
0
0
0.3
0
2
0
0
0.5
8
1
2
0
2.8
4
19
5
0
7.0
21
16
28
0
16.3
46
2
0
0
12.0
4
9
4
10
6.8
0
0
0
0
0.0
16
42
34
44
34.0
0
0
0
4
1.0
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
9
29
83
4
0
5
8
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
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10
11
12
Mean
34
41
88
62
62
44
62.7
17
23
30
18.5
0
8
22
7.5
20
5
4
8.5
1
2
0
2.8
100
100
100
100.0
9
10
11
12
Mean
29
34
41
88
830
620
620
440
627.5
28
119
161
210
129.5
0
0
40
110
37.5
20
80
20
16
34.0
8
1
2
0
2.8
886
820
843
776
831.3
88.6
82
84.3
77.6
83.1
85
95
95
95
92.5
31.2
15.4
24.8
21.9
23.3
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Thanda Mduna 2012
Table 10.
community 2
Community 2
2012
2013
84
93
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
55.0
19.0
11.0
5.0
10.0
0.0
62.7
18.5
7.5
8.5
2.8
0.0
76.8
83.1
Biomass (kg/ha)
33.7
14.3
3878
35.5
23.3
5437
3.
Ziziphus mucronata – Mundulea sericea bushveld and woodland
This community occurs on the plains, midslopes and hilltops in the Intibane area of Thanda
and the northwestern section of Mduna. The north and north-west facing slopes range from
2-15º in gradient. Density and cover estimates for the woody strata made during the 2012
vegetation survey indicated that few tall trees were encountered although trees and shrubs
were common (Table 11).
Table 11.
surveys in 2012
Plant community
Individuals per ha
Canopy cover (%)
Tall trees (>6 m)
31
6
Trees (3 - 6 m)
125
15
Shrubs (<3 m)
519
14
Shrubs minimum
325
Shrubs maximum
725
the highest frequencies in 2013 (Table 12). Once again Digitaria eriantha showed a decline
from 2012 to 2013. The veld condition index remained basically unchanged in the two years
(Table 13), with the community in an excellent condition. Grass canopy cover and height
(as indicated by the disc pasture meter) were slightly higher in 2013 than in 2012.
Grazing capacity remained almost unchanged in 2012 compared to 2013.
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Thanda Mduna 2012
Table 12.
pasture meter height for seven plots monitored in community 3 in 2013
Monitoring plot no
Brachiaria nigropedata
Chloris virgata
Cymbopogon caesius
Digitaria eriantha
Eragrostis superba
Forbs
Hyparrhenia hirta
Ischaemum afrum
Leptochloa eleusine
Melinis repens
Panicum deustum
Panicum maximum
Setaria sphacelata
Themeda triandra
Tricholaena monachne
Tristachya biseriata
Total
13
49
2
1
1
0
0
0
2
0
0
2
0
0
0
0
0
4
56
0
32
0
0
0
100
14
15
16
17
18
19
60
67
79
80
84
100
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
10
0
0
0
1
4
0
0
24
0
0
0
2
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
7
1
0
0
0
6
0
2
5
1
11
0
2
7
0
6
2
0
0
1
0
0
0
2
0
29
0
3
0
3
1
0
0
0
9
0
2
6
0
0
0
21
4
23
4
16
31
48
10
3
68
34
1
0
0
1
2
0
5
17
70
23
8
40
17
0
2
0
0
0
0
0
0
0
1
0
0
0
1
0
0
0
0
100
100
100
100
100
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
13
49
93
0
0
1
6
100
14
15
16
17
18
19
60
67
79
80
84
100
86
85
53
80
90
73
0
8
2
4
0
5
5
1
30
10
3
9
2
4
7
1
6
2
7
2
8
5
1
11
100
100
100
100
100
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
13
14
15
16
17
18
19
Mean
49
60
67
79
80
84
100
930
860
850
530
800
900
730
800.0
0
0
56
14
28
0
35
19.0
0
25
5
150
50
15
45
41.4
4
8
16
28
4
24
8
13.1
6
7
2
8
5
1
11
5.7
940
900
929
730
887
940
829
879.3
94.0
90.0
92.9
73.0
88.7
94.0
82.9
87.9
95
95
95
92
95
80
95
92.4
37.3
15.0
24.0
25.5
33.1
14.1
22.5
24.5
Ekotrust CC
23
Mean
0.4
0.1
0.1
1.4
4.1
0.3
0.3
0.3
1.1
3.9
2.4
0.1
4.9
1.9
1.1
14.7
31.4
1.1
29.6
0.3
0.1
0.1
100.0
Mean
80.0
2.7
8.3
3.3
5.7
100.0
Thanda Mduna 2012
Table 13.
community 3
Community 3
2012
2013
82
92
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
75.0
9.0
5.0
2.0
9.0
0.0
80.0
2.7
8.3
3.3
5.7
0.0
86.0
87.9
Biomass (kg/ha)
38.0
21.0
4840
39.4
24.5
5621
4.
Combretum apiculatum – Aloe marlothii open bushveld and woodland
This open bushveld and woodland covers approximately 1787 ha (about 12% of the
Reserve) and occurs on footslopes, midslopes and low hills in the northern parts of Mduna.
The north and east-facing slopes range from 2-15º in gradient. Estimates of woody cover and
density made during the 2012 vegetation survey are provided in Table 14 for descriptive
purposes.
Table 14.
surveys in 2012
Plant community
Individuals per ha
Canopy cover (%)
Tall trees (>6 m)
45
6
Trees (3 - 6 m)
130
8
Shrubs (<3 m)
690
10
Shrubs minimum
275
Shrubs maximum
1300
In both years Themeda triandra and Panicum deustum ranked first and second in terms of
frequency (Table 15). In 2013 Panicum maximum had the third highest frequency, whereas
Digitaria eriantha was ranked third in 2012. All these species are classified as Class 1 species.
The veld was in excellent condition in both years with the grass canopy cover values also
similar (Table 16). The settling height of the disc pasture meter was higher in 2013 than in
2012.
Grazing capacity in community 4 remained unchanged in 2012 compared to 2013.
Ekotrust CC
24
Thanda Mduna 2012
Table 15.
pasture meter height for ten plots monitored in community 4 in 2013
Monitoring plot no
Bare soil
Cenchrus ciliaris
Chloris virgata
Cymbopogon pospischilii
Cymbopogon caesius
Cymbopogon nardus
Cynodon dactylon
Digitaria eriantha
Forbs
Hyparrhenia filipendula
Ischaemum afrum
Leptochloa eleusine
Melinus repens
Panicum coloratum
Panicum deustum
Panicum maximum
Setaria incrassata
Setaria sphacelata
Sporobolus ioclados
Themeda triandra
Total
20
33
0
0
0
0
0
1
0
0
0
0
0
0
10
3
0
0
0
0
0
28
5
0
5
0
48
0
100
21
36
0
0
1
2
0
0
0
0
0
0
1
0
2
15
0
0
0
0
0
8
28
0
0
0
43
0
100
22
23
24
25
26
27
28
38
39
40
45
64
70
73
2
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
6
0
1
0
0
0
0
0
1
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
2
1
7
2
3
5
1
1
16
6
3
0
0
8
7
0
0
0
0
2
0
0
0
0
1
0
0
0
0
0
7
0
0
0
0
0
0
0
0
0
0
1
2
0
0
3
0
0
0
0
0
10
25
24
25
11
15
30
6
2
10
7
3
6
16
0
1
0
0
0
0
0
2
0
7
0
0
3
0
0
0
0
0
0
0
0
58
62
55
58
76
63
31
0
0
0
0
0
0
0
100
100
100
100
100
100
100
29
202
0
1
1
0
1
0
0
0
0
0
0
0
23
0
0
0
2
0
2
16
41
0
0
2
8
3
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Bare soil
Total
20
33
81
5
1
3
10
0
100
21
36
81
1
0
15
3
0
100
22
38
75
2
7
6
10
0
100
23
24
25
26
27
28
39
40
45
64
70
73
92
89
90
90
85
77
1
7
0
0
5
1
1
1
2
0
0
6
4
0
0
8
7
0
2
3
8
2
3
16
0
0
0
0
0
0
100
100
100
100
100
100
29
202
67
3
2
3
24
1
100
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
20
33
810
35
5
12
10
872
87.2
95
15.9
21
22
23
24
25
26
27
28
29
36
38
39
40
45
64
70
73
202
810 750
920
890
900
900
850
770
670
7
14
7
49
0
0
35
7
21
0
35
5
5
10
0
0
30
10
60
24
16
0
0
32
28
0
12
3
10
2
3
8
2
3
16
24
880 833
950
947
918
934
916
823
737
88.0 83.3 95.0 94.7 91.8 93.4 91.6 82.3 73.7
95
95
95
95
90
92
82
85
35
16.9 17.9 21.4 26.9 24.9 23.0 28.1 32.0
4.9
Ekotrust CC
25
Mean
0.2
0.1
0.6
0.2
0.1
0.1
0.1
0.6
0.1
0.2
0.1
0.3
7.0
4.2
0.2
0.1
0.9
0.3
0.5
19.2
12.4
0.1
1.7
0.2
50.2
0.3
100.0
Mean
82.7
2.5
2.0
4.6
8.1
0.1
100.0
Mean
827.0
17.5
10.0
18.4
8.1
881.0
88.1
85.9
21.2
Thanda Mduna 2012
Table 16.
community 4
Community 4
2012
2013
90
86
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
81.0
1.0
5.0
4.0
9.0
0.0
82.7
2.5
2.0
4.6
8.1
0.1
86.7
88.1
Biomass (kg/ha)
40.1
15.4
4258
40.0
21.2
5104
5.
Acacia burkei – Panicum maximum open bushveld and woodland
This community is divided into two subcommunities and occurs on footslopes, midslopes and
hilltops in the eastern and central parts of Mduna. Veld condition assessments in 2013 were
done for the community as a whole and were not separated by subcommunity. Density and
cover values for the woody strata made during the 2012 vegetation survey are provided in
Table 17.
Table 17.
surveys in 2012
Subcommunity
Tall trees (>6 m)
Individuals per ha
Canopy cover (%)
5a
5b
25
8
1a
2
1b
6
Trees (3 - 6 m)
25
67
6
9
Shrubs (<3 m)
600
779
8
11
Shrubs minimum
-
733
Shrubs maximum
-
825
the highest frequencies in 2013 (Table 18). Once again Digitaria eriantha showed a decline
from 2012 to 2013. The veld condition index was marginally higher in 2013 (Table 19), with the
community in an excellent condition in both years. Grass canopy cover was slightly higher in
2013 than in 2012, whereas grass height (as indicated by the disc pasture meter) was
noticeably higher in 2013 than in 2012.
There was basically no difference in grazing capacity between 2012 and 2013.
Ekotrust CC
26
Thanda Mduna 2012
Table 18.
Frequency of species, classes and veld condition index, grass cover and
disc pasture meter height for five plots monitored in community 5 in 2013
Monitoring plot no
Aristida congesta ssp. barbicollis
Brachiaria serrata
Cymbopogon pospishilii
Cymbopogon caesius
Digitaria eriantha
Forbs
Leptochloa eleusine
Melinus repens
Panicum coloratum
Panicum deustum
Panicum maximum
Setaria incrassata
Themeda triandra
Trichoneura grandiglumis
Tristachya leucothrix
Total
30
26
0
3
0
0
0
2
0
1
0
0
0
2
28
27
3
34
0
0
0
0
100
31
32
33
34
Mean
48
75
94
97
0
0
0
1
0.2
0
0
4
0
1.4
0
0
0
4
0.8
0
0
0
5
1.0
0
0
0
1
0.2
0
0
2
2
1.2
0
1
0
0
0.2
1
16
1
3
4.4
0
0
0
17
3.4
0
0
0
2
0.4
0
0
0
1
0.2
0
0
0
0
0.4
14
44
28
27
28.2
60
33
21
1
28.4
0
0
1
0
0.8
25
6
42
27
26.8
0
0
0
2
0.4
0
0
0
6
1.2
0
0
0
1
0.2
0
0
1
0
0.2
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
30
26
93
3
0
0
4
100
31
32
33
34
Mean
48
75
94
97
99
83
93
57
85.0
0
0
2
0
1.0
0
0
0
8
1.6
0
1
0
24
5.0
1
16
5
11
7.4
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
Frequency of occurrence (%) of classes X class
multiplier
30
31
32
33
34
Mean
26
48
75
94
97
930
990
830
930
570
850.0
21
0
0
14
0
7.0
0
0
0
0
40
8.0
0
0
4
0
96
20.0
4
1
16
5
11
7.4
955
991
850
949
717
892.4
95.5
99.1
85.0
94.9
71.7
89.2
95
98
90
95
75
90.6
23.0
36.2
28.3
22.8
18.4
25.7
Ekotrust CC
27
Thanda Mduna 2012
Table 19.
community 5
Community 5
2012
2013
84
91
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
77.0
2.0
8.5
0.0
12.5
0.0
85.0
1.0
1.6
5.0
7.4
0.0
83.9
89.2
Biomass (kg/ha)
44.8
13.5
4114
45.7
25.7
5800
6.
Olea capensis – Mystroxylon aethiopicum ridge bushveld
This community occurs on ridges/dykes and covers only 0.5% of the reserves and was
therefore not monitored.
7.
Olea europaea – Berchemia zeyheri bushveld and thickets
This community occurs on midslopes and hilltops in the southern parts of Mduna as well as
steep southfacing midslopes in the central parts of Thanda. Two subcommunities are
recognized with subcommunity 7a being an open bushveld, whereas subcommunity 7b is
classified as a thicket with high canopy cover values for small trees and shrubs (Table 20).
Veld condition assessments in 2013 were done for the community as a whole and not by
subcommunity.
Table 20.
surveys in 2012
Canopy cover (%)
Subcommunity
7a
7b
Tall trees (>6 m)
2
7
Trees (3 - 6 m)
6
38
Shrubs (<3 m)
7
35
A relatively small number of grass species were recorded in this community in 2013, with
Panicum maximum dominating (frequency 62%, Table 21). Forbs and grasses (Class 5
species) had the second highest frequency of 16.4% in 2013, compared to 21% in 2012. In
2012 frequencies were more evenly spread between the grass species Panicum maximum,
Themeda triandra and Panicum deustum. The veld condition was notably higher in 2013
than in 2012 (index 84.1% as against 67.0, Table 22) and showed an improvement from
Ekotrust CC
28
Thanda Mduna 2012
moderate to excellent. Grass canopy cover was however slightly lower in 2013 than in 2012.
No disc pasture meter measurements were taken in 2012.
There was basically no difference in grazing capacity between 2012 and 2013 (Table 22).
Table 21.
disc pasture meter height for five plots monitored in community 7 in 2013
Monitoring plot no
Cymbopogon caesius
Digitaria eriantha
Forbs
Ischaemum afrum
Panicum deustum
Panicum maximum
Themeda triandra
Total
35
78
0
1
0
17
0
0
77
5
100
36
37
38
39
Mean
85
90
91
92
2
4
0
0
1.2
0
0
0
0
0.2
0
0
0
1
0.2
52
2
10
1
16.4
0
0
0
5
1.0
0
8
2
21
6.2
40
70
88
37
62.4
6
16
0
35
12.4
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
35
78
83
0
0
0
17
100
36
37
38
39
Mean
85
90
91
92
46
94
90
93
81.2
0
0
0
1
0.2
2
4
0
5
2.2
0
0
0
0
0.0
52
2
10
1
16.4
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
Ekotrust CC
35
36
37
38
39
Mean
78
85
90
91
92
830
460
940
900
930
812.0
0
0
0
0
7
1.4
0
10
20
0
25
11.0
0
0
0
0
0
0.0
17
52
2
10
1
16.4
847
522
962
910
963
840.8
84.7
52.2
96.2
91.0
96.3
84.1
35
30
95
45
95
60.0
15.5
4.5
42.4
21.3
35.6
23.9
29
Thanda Mduna 2012
Table 22.
community 7
Community 7
2012
2013
68
60
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
63.0
0.0
4.0
0.0
21.0
12.0
81.2
0.2
2.2
0.0
16.4
0.0
67.1
84.1
Biomass (kg/ha)
35.2
-
35.5
23.9
5529
8.
Olea europaea – Clerodendrum glabrum – Ehretia amoena dense bushveld and
thickets
This community occurs on slopes in the valleys in the southwestern parts of Mduna. The
community is a dense bushveld or thicket with high cover values for trees and shrubs (Table
23). The herbaceous layer is generally moderately developed between the bush clumps but
within the bush clumps it is poorly developed. Forbs are fairly prominent in the community.
Table 23.
surveys in 2012
Subcommunity
Canopy
cover (%)
Tall trees (>6 m)
12
Trees (3 - 6 m)
22
Shrubs (<3 m)
23
The dominant grass species in both 2012 and 2013 were Panicum maximum and Panicum
deustum. Forbs and grasses (Class 5) contributed 20.5% to the total frequency in 2013,
compared to 17% in 2012 (Table 25). Veld condition was notably higher in 2013 than in 2012
(index 77.7% in 2013 as against 48.0% in 2012, Table 25) and showed an improvement from
poor to good/excellent. Grass canopy cover showed an increase from 2012 to 2013, but
grass height (as indicated by the disc pature meter height) was similar.
Ekotrust CC
30
Thanda Mduna 2012
Table 24.
disc pasture meter height for two plots monitored in community 8 in 2013
Monitoring plot no
Aristida bipartita
Eragrostis sp.
Forbs
Leptochloa eleusine
Panicum deustum
Panicum maximum
Setaria incrassata
Themeda triandra
Total
40
41
Mean
4
76
1
0
10
0
20
20
1
0
47
0
5
80
4
0
12
0
100
100
0.5
5.0
20.0
0.5
23.5
42.5
2.0
6.0
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
40
41
Mean
4
76
64
80
4
0
1
0
10
0
21
20
100
100
72.0
2.0
0.5
5.0
20.5
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
40
41
Mean
4
76
640
800
720.0
28
0
14.0
5
0
2.5
40
0
20.0
21
20
20.5
734
820
777.0
73.4
82.0
77.7
60
60
60.0
10.9
16.6
13.8
Ekotrust CC
31
Thanda Mduna 2012
Table 25.
community 8
Community 8
2012
2013
48
60
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
48.0
5.0
7.0
4.0
17.0
19.0
72.0
2.0
0.5
5.0
20.5
0.0
58.3
77.7
Biomass (kg/ha)
32.4
14.4
3858
38.4
13.8
3779
9.
Acacia xanthophloa – Spirostachys africana riparian vegetation
The herbaceous layer in this community was not monitored.
10.
Euphorbia tirucalli – Ficus abutilifolia ridge bushveld
This community was not monitored.
11.
This community is divided into two subcommunties and occurs mainly on the plains in the
eastern parts of Thanda. The woody layer in subcommunity 11b is denser than that of
subcommunity 11a (Table 26). As a consequence of the dense woody layer in
subcommunity 11b the grass layer is poorly developed. Veld condition assessments in 2013
were done for the community as a whole and were not separated by subcommunity.
Table 26.
Density and cover of woody strata in community 11 as established during
field surveys in 2012
Individuals per ha
Canopy cover (%)
11a
11b
2
13
1a
2
1b
25
Trees (3 - 6 m)
107
226
20
22
Shrubs (<3 m)
769
894
22
50
Shrubs minimum
725
788
Shrubs maximum
812
1000
Subcommunity
Tall trees (>6 m)
Ekotrust CC
32
Thanda Mduna 2012
Table 27.
disc pasture meter height for six plots monitored in community 11 in 2013
Monitoring plot no
Aristida bipartita
Aristida congesta ssp. barbicollis
Bare soil
Brachiaria eruciformis
Chloris virgata
Digitaria eriantha
Enneapogon cenchroides
Eragrostis curvula
Eragrostis sp.
Forbs
Leptochloa eleusine
Panicum coloratum
Panicum deustum
Panicum maximum
Setaria incrassata
Setaria sphacelata
Sporobolus ioclados
Themeda triandra
Total
42
14
0
0
0
0
0
0
0
1
0
0
0
0
0
1
0
0
0
45
25
4
0
0
24
0
100
43
44
45
46
47
Mean
15
22
23
68
69
4
1
0
1
0
1.0
0
2
0
0
0
0.3
2
3
0
0
0
0.8
0
0
0
10
0
1.7
0
12
7
0
0
3.2
0
1
0
1
0
0.3
0
1
0
0
0
0.2
0
0
0
0
0
0.2
1
0
0
0
0
0.2
6
1
0
0
0
1.2
4
0
0
2
0
1.0
0
19
17
5
0
6.8
0
4
0
0
0
0.7
16
4
0
10
36
11.2
0
0
5
0
0
0.8
16
4
0
2
0
3.7
0
4
6
0
4
2.3
0
0
6
10
0
10.2
31
12
17
55
44
30.7
0
0
0
0
0
0.7
0
3
1
0
0
0.7
1
2
0
0
0
0.5
4
23
37
0
14
17.0
15
4
4
4
2
4.8
100
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Bare soil
Total
42
14
95
4
0
0
1
0
100
43
44
45
46
47
Mean
15
22
23
68
69
35
39
66
65
62
60.3
19
11
5
8
2
8.2
16
4
0
0
0
3.3
1
22
22
5
0
8.3
29
24
7
12
36
18.2
0
0
0
10
0
1.7
100
100
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
42
43
44
45
46
47
Mean
14
15
22
23
68
69
950
350
390
660
650
620
603.3
28
133
77
35
56
14
57.2
0
80
20
0
0
0
16.7
0
4
88
88
20
0
33.3
1
29
24
7
12
36
18.2
979
596
599
790
900
670
729
97.9
59.6
59.9
79.0
90.0
67.0
72.9
95
80
90
90
20
55
71.7
30.9
12.4
8.0
11.6
3.0
12.8
13.1
Ekotrust CC
33
Thanda Mduna 2012
Panicum maximum, Themeda triandra and Panicum deustum were the three grass species
with the highest frequencies in both 2012 and 2013 (Table 27). All three species are classified
as Class 1 species. Class 2 to Class 5 grass species made a larger contribution to the species
composition in communities 11 and 12 than in communities 1 – 5, 7 and 8. Forbs and grasses
(Class 5) had the highest frequency in 2012 and were still prominent in 2013 (19.4%). Veld
condition was notably higher in 2013 than in 2012 (index 72.7% in 2013 as against 56.0 in
2012, Table 28) and showed an improvement from moderate to good/excellent. Grass
canopy cover and grass height (as indicated by the disc pature meter height) showed a
marked increase from 2012 to 2013. Grazing capacity increased notably from 31.1 GU / 100
ha in 2012 to 40.1 GU /100 ha in 2013.
Table 28.
community 11
Community 11
2012
2013
39
72
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
39.5
7.0
11.0
9.5
24.5
8.5
60.3
8.2
3.3
8.3
18.2
1.7
56.2
72.9
Biomass (kg/ha)
31.1
8.3
2344
40.1
13.1
3637
12.
Acacia nilotica – Urochloa mosambicensis old fields and other disturbed areas
This open to dense thornveld occurs on abandoned fields and other disturbed areas on the
eastern lowland plains. Tall trees (>6 m) were virtually absent but shrubs occurred at a high
density (Table 29).
Table 29
Density and cover of woody strata in community 12 as established during
field surveys in 2012
Plant community
Individuals per ha
Canopy cover (%)
Tall trees (>6 m)
0
<1
Trees (3 - 6 m)
74
4
Shrubs (<3 m)
928
28
Shrubs minimum
570
Shrubs maximum
1425
Ekotrust CC
34
Thanda Mduna 2012
Table 30.
pasture meter height for three plots monitored in community 12 in 2013
Monitoring plot no
Chloris virgata
Digitaria argyrograpta
Digitaria eriantha
Enneapogon scoparius
Eragrostis sp.
Forbs
Leptochloa eleusine
Panicum coloratum
Panicum maximum
Setaria incrassata
Themeda triandra
Total
48
49
50
Mean
11
18
19
0
0
1
0.3
0
0
6
2.0
0
0
4
1.3
0
0
1
0.3
0
0
1
0.3
0
3
0
1.0
0
1
0
0.3
0
3
1
1.3
0
6
4
3.3
0
25
16
13.7
0
20
1
7.0
0
13
39
17.3
90
20
7
39.0
0
0
13
4.3
2
0
0
0.7
8
9
6
7.7
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Total
48
49
50
Mean
11
18
19
92
33
47
57.3
8
9
20
12.3
0
20
1
7.0
0
6
8
4.7
0
32
24
18.7
100
100
100
100.0
Monitoring plot no
Class 1
Class 2
Class 3
Class 4
Class 5
Grass cover (%)
48
49
50
Mean
11
18
19
920
330
470
573.3
56
63
140
86.3
0
100
5
35.0
0
24
32
18.7
0
32
24
18.7
976
549
671
732.0
97.6
54.9
67.1
73.2
80
85
80
81.7
10.5
9.5
5.7
8.6
Panicum maximum dominated the grass layer in both years (Table 30). Panicum deustum
and Eragrostis sp. had the second highest frequencies in 2013 and 2012 respectively. Forb
frequency was similar in both years, but in 2012, 15% of all points were bare soil, with no bare
soil recorded in 2013.
Ekotrust CC
35
Thanda Mduna 2012
Veld condition was notably higher in 2013 than in 2012 (index 73.2% as against 46.0, Table
31) and showed an improvement from poor to good/excellent. Both grass canopy cover
and grass height (as indicated by the disc pature meter height) showed a marked increase
from 2012 to 2013 (Table 31).
Grazing capacity increased notably from 31.7 GU / 100 ha in 2012 to 45.9 GU /100 ha in
2013.
Table 31.
community 12
Community 12
2012
2013
36
82
Class 1 (%)
Class 2 (%)
Class 3 (%)
Class 4 (%)
Class 5 (%)
Bare soil (%)
23.0
11.0
24.0
1.0
31.0
10.0
57.3
12.3
7.0
4.7
18.7
46.2
73.2
Biomass (kg/ha)
31.7
4.0
1252
45.9
8.6
2617
4.3
Biomass per community
Overall, there was a marked increase in herbaceous biomass in all the communities (with
the exception of community 8) in 2013 as compared to 2012 (Table 32). Highest biomass per
community in 2013 was recorded for community 5 and the lowest for community 12. In 2012
community 9 had the highest biomass. However, this community was not monitored in 2013.
Lowest biomass in 2012 was also recorded in community 12.
With the exception of community 12 all mean herbaceous biomass values in 2013 exceeded
3000 kg/ha.
4.4
Grazing capacity
Rainfall is the main determinant of forage production in the savanna environment. Since
rainfall varies widely from year to year, often with an alternating series of wet and dry years,
forage production varies widely over time. Consequently regular field surveys have to be
Ekotrust CC
36
Thanda Mduna 2012
done to advise on adjusting the stocking densities to the quantity and quality of the
vegetation in a given period.
Table 32.
Mean grass biomass of the plant communities of Thanda and Mduna in 2012
and 2013
Community
1 (entire)
1a
1b
2
3
4
5 (entire)
5a
5b
7 (entire)
7a
7b
8
11 (entire)
11a
11b
12
Mean
Ekotrust CC
Area
ha
2341
1014
1327
572
704
1772
1896
975
921
1074
266
808
1674
1528
702
826
365
Biomass
kg/ha
2012
4059
3677
4440
3878
4840
4258
4114
4350
3878
3858
2344
2814
1873
1252
3676
Biomass
kg/ha
2013
4652
4128
5149
5437
5621
5104
5800
5815
5793
5529
6828
2957
3779
3637
3669
3491
2617
4710
37
Thanda Mduna 2012
Table 33.
Veld condition and grazing capacity of Thanda and Mduna combined at mean annual rainfall (845 mm). The ridges (communities 6 & 10)
were not surveyed.
1a
1b
1
entire
2
3
4
5a
5b
5
enitre
7a
7b
7
entire
8
9a
9b
11a
11b
11
entire
12
Total
1014
1327
2341
572
704
1772
975
921
1896
266
808
1074
1674
1584
543
702
826
1528
365
20892
Percentage tree cover
9
17
13
10
21
14
8
15
12
8
45
27
30
25
40
23
40
32
4
Percentage shrub cover
10
12
11
14
14
10
8
11
10
7
35
21
23
11
13
22
50
36
28
0.91
0.85
0.88
0.89
0.81
0.87
0.92
0.86
0.89
0.92
0.58
0.75
0.72
0.80
0.69
0.77
0.57
0.67
0.88
Class 1
65.0
86.0
75.5
55.0
75.0
81.0
75.0
79.0
77.0
70.0
56.0
63.0
48.0
74.0
44.0
52.0
27.0
39.5
23.0
Class 2
9.0
2.0
5.5
19.0
9.0
1.0
4.0
0.0
2.0
0.0
0.0
0.0
5.0
4.0
1.0
4.0
10.0
7.0
11.0
Class 3
5.0
0.0
2.5
11.0
5.0
5.0
9.0
8.0
8.5
8.0
0.0
4.0
7.0
9.0
8.0
5.0
17.0
11.0
24.0
Class 4
9.0
1.0
5.0
5.0
2.0
4.0
0.0
0.0
0.0
0.0
0.0
0.0
4.0
1.0
3.0
13.0
6.0
9.5
1.0
Class 5
12.0
11.0
11.5
10.0
9.0
9.0
12.0
13.0
12.5
22.0
20.0
21.0
17.0
12.0
20.0
19.0
30.0
24.5
31.0
10.0
Plant community
Area (ha)
Bush factor
Ecological classes (%)
Bare area
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
24.0
12.0
19.0
0.0
24.0
7.0
10.0
8.5
Total
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
100
78.6
88.9
83.8
76.8
85.5
86.7
83.5
84.3
83.9
76.2
58.0
67.1
58.3
82.9
51.9
64.4
47.9
56.2
46.2
Percentage grass cover
84
90
87
84
82
90
85
83
84.0
88
48
68.0
48
79
50
64
13
38.5
36
Mean annual rainfall
845
845
845
845
845
845
845
845
845
845
845
845
845
845
845
845
845
845
845
Accessibility
1.0
1.0
1.0
0.8
0.9
0.9
1.0
1.0
1.0
0.9
0.8
0.9
0.8
0.8
0.8
0.8
0.8
0.8
1.0
Fire
0.8
Ecological grazing capacity at mean annual
rainfall
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
0.8
1.0
0.9
1.0
1.0
1.0
1.0
1.0
1.0
0.9
Number GU per 100 ha
62
63
62
48
54
57
65
61
63
57
51
50
46
59
46
51
24
44
45
Number GU (game)
629
839
1459
275
383
1014
634
565
1186
151
412
539
775
934
248
357
196
678
165
Mean grazing capacity (GU per 100 ha) =
Economical grazing capacity at mean annual
rainfall
55
43.4
44.3
43.6
33.7
38.0
40.1
45.5
43.0
43.8
39.8
35.7
35.2
32.4
41.3
32.0
35.6
16.6
31.1
31.7
Number GU (game)
440
588
1022
193
268
710
444
396
830
106
289
378
543
654
174
250
137
475
116
Ekotrust CC
11440
8008
38
38
Thanda Mduna 2012
Table 34.
Veld condition and grazing capacity of Thanda and Mduna combined in
2013 at mean annual rainfall (845 mm)
Plant community
Area (ha)
1
2
3
4
5
7
8
11
12
2341
572
704
1772
1896
1074
1674
1528
Percentage tree cover
13
10
21
14
12
27
30
32
4
Percentage shrub cover
11
14
14
10
10
21
23
36
28
0.88
0.89
0.81
0.87
0.89
0.75
0.72
0.67
0.88
Class 1
78.7
62.7
80.0
82.7
85.0
81.2
72.0
60.3
57.3
Class 2
10.0
18.5
2.7
2.5
1.0
0.2
2.0
8.2
12.3
Class 3
1.5
7.5
8.3
2.0
1.6
2.2
0.5
3.3
7.0
Class 4
2.8
8.5
3.3
4.6
5.0
0.0
5.0
8.3
4.7
Class 5
7.0
2.8
5.7
8.1
7.4
16.4
20.5
18.2
18.7
Bush factor
Total
365 11926
Ecological classes (%)
Bare area
0.0
0.0
0.0
0.1
0.0
0.0
0.0
1.7
0.0
Total
100.0
100.0
100.0
100.0
100.0
100.0
100.0
100.0
100.0
88.3
83.1
87.9
88.1
89.2
84.1
77.7
72.9
73.2
Percentage grass cover
90
93
92
86
91
60
60
72
82
Mean annual rainfall
845
845
845
845
845
845
845
845
845
Accessibility
1.0
0.8
0.9
0.9
1.0
0.9
0.8
0.8
1.0
Fire
0.8
0.8
0.8
0.8
0.8
0.8
1.0
1.0
0.9
Ecological grazing capacity at mean annual rainfall
Number GU (game)
64
51
56
57
65
51
55
57
66
1505
290
396
1013
1238
545
919
875
239
7020
59
Economical grazing capacity at mean annual rainfall
45.0
35.5
39.4
40.0
45.7
35.5
38.4
40.1
45.9
Number GU (game)
1053
203
277
709
867
381
643
612
167
41
The ecological and economical grazing capacities in 2013 of Thanda and Mduna
combined, at a mean annual rainfall of 845 mm were approximately 59 Grazer Units per 100
ha (= 3.4 ha/LAU) and 41 Grazer Unit per 100 ha (= 4.9 ha/LAU) respectively (Table 34).
Concommitant with the general increase in veld condition and increase in biomass there
was an increase in grazing capacity in 2013. Communities 1, 5 and 12 had the highest
grazing capacities, whereas communities 2 and 7 had the lowest grazing capacities.
4.5
Browsing capacity
Browse is the sum total of woody plant material that is potentially edible for a specific set of
herbivores in a specific area. The term available browse indicates a more restricted quantity
and includes all the leaves, twigs, bark, flowers and pods that are within reachable height of
a given type of browser. The browsable volume is usually limited to the foliage up to 2 m for
most browsers, and up to 5.5 m for the giraffe and African savanna elephant.
Ekotrust CC
4914
39
Thanda Mduna 2012
Browsers are limited by their food supply rather than other factors such as water and
territoriality. The browse supply in the late dry season (August to October) imposes a limit on
the stocking density for browsers. Greater kudu mortalities in the bushveld region of South
Africa have been attributed to sudden cold spells (pneumonia), disease (anthrax) and, most
importantly, the lack of evergreen palatable plant species for the kudus to survive the late
dry season (low resource availability).
The browsing capacity of Thanda and Mduna can be assessed after the woody vegetation
monitoring has been done.
4.6
Alternative approaches to determine the ecological and economical capacity of
Thanda
Other methods are available to estimate short and long-term grazing and browsing
capacities. These methods were developed in savanna regions of southern Africa. In most of
these methods, the ecological capacity is expressed in terms of a Large Animal Unit (LAU),
which is the equivalent of a steer of 450 kg and a dry matter intake of 10 kg/day. The
recommended agricultural grazing capacity for most of the area covered by Thanda and
Mduna is estimated at 5 to 7 ha/LAU (Agricultural Research Council 2007).
•
Combined veld condition and rainfall method (Danckwerts 1989)
This model was developed in the Eastern Cape province of South Africa:
GC = {-0.03 +0.00289 x (X1) + [(X2 - 419.7) x 0.000633]}
where: GC
= grazing capacity in large animal units per hectare (LAU/ha)
X1
= veld condition index (%)
X2
= mean annual rainfall (here 845 mm)
Using the veld condition indices and a mean annual rainfall of 845 mm, the ecological
grazing capacity for Thanda and Mduna in 2013 was calculated as 2.1 ha/LAU (= 95 Grazer
Units per 100 ha). If the economical grazing capacity is taken as 70% of the ecological
grazing capacity, an economical capacity of approximately 3.0 ha/LAU (= 67 Grazer Units
per 100 ha) for Thanda and Mduna is obtained.
There was a slight increase in grazing capacity, as calculated by the Combined veld
condition and rainfall method, compared to 2012 when the ecological grazing capacity for
Thanda and Mduna was calculated as 2.2 ha/LAU (= 91 Grazer Units per 100 ha) and the
economical grazing capacity was 3.1 ha/LAU (= 64 Grazer Units per 100 ha).
Ekotrust CC
40
Thanda Mduna 2012
•
Herbaceous phytomass method (Moore & Odendaal 1987)
The grazing capacity for grazer species is calculated from herbaceous phytomass data (see
Table 34) by using the following equation:
SR
phytomass (kg/ha) x 0.35b/(10bb x 365bbb)
=
where:
SR
=
stocking density in large animal units per hectare per year
b
=
a utilisation factor: only 35% of the herbaceous material is grazed while 30%
remains as tufts and stubbles and 25% is lost to other environmental factors
bb
=
10 kg feed per day is required per large stock unit
bbb
=
number of days in a year
The phytomass of the herbaceous layer was determined with the Disc Pasture Meter
(Trollope & Potgieter 1986; Dörgeloh 2002; Zambatis et al. 2006; Table 34), which provides a
measure of the dry mass of the available grass in a given area. The grass biomass of rocky
areas, thickets and riparian vegetation were not measured. The grazing capacity of Thanda
according to this method is approximately 2.2 ha/LAU (= 91.3 Grazer Units per 100 ha). If the
economical grazing capacity is taken as 70% of the ecological grazing capacity, an
economical capacity of approximately 3.1 ha/LAU (= 63.9 Grazer Units per 100 ha) is
obtained (Table 36).
Table 35.
Mean grass biomass of the different plant communities of Thanda and
Mduna in 2012. Grazing capacities were calculated with the Moore &
Odendaal (1987)
Community
1a
1b
2
3
4
5a
5b
8
9a
11a
11b
12
Total
Area
Biomass
ha
kg/ha
LAU/ha
1014
1327
572
704
1772
975
921
1674
1609
702
826
365
12461
3677
4440
3878
4840
4258
4350
3878
3858
4990
2814
1873
1252
0.35
0.43
0.37
0.46
0.41
0.42
0.37
0.37
0.48
0.27
0.18
0.12
Mean (ha/LAU)
Mean (GU/100 ha)
Ekotrust CC
41
Grazing capacity
LAU
LAU
ha/LAU
ecological Economical
2.8
355
248
2.3
571
399
2.7
212
148
2.2
324
227
2.4
727
509
2.4
410
287
2.7
341
239
2.7
619
434
2.1
3.7
190
133
5.6
149
104
8.3
44
31
4712
3296
2.6
3.8
75.8
52.9
Thanda Mduna 2012
There was a slight increase in grazing capacity, as calculated by the herbaceous phytomass
method, compared to 2012 when the ecological grazing capacity for Thanda and Mduna
was calculated as 2.6 ha/LAU (= 76 Grazer Units per 100 ha) and the economical grazing
capacity was 3.8 ha/LAU (= 53 Grazer Units per 100 ha).
Table 36.
Mean grass biomass of the different plant communities of Thanda and
Mduna in 2013. Grazing capacities were calculated with the Moore &
Odendaal (1987)
Grazing capacity
Community
ha
kg/ha
1
2341
4652
2
572
5437
3
704
5621
4
1772
5104
5
1896
5800
7
1074
5529
8
1674
3779
11
1528
3637
12
365
2617
Total
11926
4686
Mean grazing capacity
(ha/LAU)
Mean grazing capacity
(GU/100 ha)
•
LAU/ha
0.45
0.52
0.54
0.49
0.56
0.53
0.36
0.35
0.25
ha/LAU
Ecological
2.2
1.9
1.9
2.0
1.8
1.9
2.8
2.9
4.0
ha/LAU
Economical
3.2
2.7
2.7
2.9
2.6
2.7
3.9
4.1
5.7
LAU
Ecological
1044
298
379
867
1054
569
607
533
92
5444
LAU
Economical
731
209
266
607
738
399
425
373
64
3811
2.37
3.39
2.19
3.13
84.3
59.0
91.3
63.9
Rainfall method (Coe, Cumming & Phillipson 1976)
In African savannas a significant relationship was found (r² = 0.94, P < 0.001) between rainfall
(range: 165 to 650 mm) and large herbivore biomass (range: 405 to 4 848 kg/km²). The
equation derived was:
Large Herbivore Biomass (kg/km²) = 8.684 x (mean annual rainfall in mm) - 1205.9
The herbivore biomass data included wildlife counts from east and southern Africa and a
wide range of the most common large African grazers and browsers. Herbivore biomass
estimates that were obtained from the above equation would therefore represent first
approximations of the combined grazing and browsing capacity of an area.
According to this equation, and at 845 mm mean annual rainfall, the large herbivore
biomass for Thanda and Mduna calculates to 6132 kg/km² or 879 819 kg for the 14 348 ha of
the reserve (excluding habitation). In terms of LAU this converts to about 1955 LAU. As a
result, an ecological stocking density of 7.3 ha/LAU (27.4 Grazer Units per 100 ha) is obtained.
Ekotrust CC
42
Thanda Mduna 2012
By comparison, the approximate economical capacities (ha/LAU) for Thanda and Mduna,
determined by different methods for 2013 are:
Estimate
Agricultural
Research
Council
estimates
(2007)(only grazers):
GU/BU method (Bothma et al. 2004) (grazers,
mixed feeders and browsers):
Veld condition/rainfall method (Danckwerts
1989)(only grazers):
Herbaceous phytomass method (Moore &
Odendaal 1987)(only grazers):
Rainfall/wildlife biomass method (Coe et al.
1976)(grazers, mixed feeders and browsers):
Ekotrust CC
43
Ecological
Economical
ha/LAU
ha/LAU
2012
2013
2012
2013
5-7
5-7
3.6
3.4
5.3
4.9
2.2
2.1
3.1
3.0
2.6
2.2
3.8
3.1
7.3
7.3
Thanda Mduna 2012
ACKNOWLEDGEMENTS
We would like to thank Wayne Matthews and Warren Beets for the professional way they
facilitated the project, and the assistance of Warren during the field word on Thanda and
Mduna.
REFERENCES
ACOCKS, J.P.H. 1953, 1988. Veld types of South Africa. Memoir of the Botanical Survey of
South Africa 57: 1-146.
BOON, R. 2010. Pooley’s Trees of eastern South Africa – a complete guide. Fauna & Flora
Publications Trust, Durban.
BOTHMA, J. DU. P. & VAN ROOYEN, N. (Eds) 2005. Intensive wildlife production in southern
Africa. Van Schaik, Pretoria.
BROMILOW,
C.
2010.
Probleemplante
en
Indringeronkruide
van
Suid-Afrika.
Briza
Publications, Pretoria.
BROUSSE-JAMES & ASSOCIATES. 2008. Thanda Private Game Reserve Management Plan.
Draft report.
COATES-PALGRAVE, K & COATES-PALGRAVE, M. 2003. Trees of southern Africa. 3rd edition.
Struik, Cape Town.
COE, M.J., CUMMING, D.H. & PHILLIPSON, J. 1976. Biomass and production of large African
herbivores in relation to rainfall and primary production. Oecologia 22: 341 354.
COETZEE, K. 2005. Caring for rangelands. University of KwaZulu-Natal Press, Pietermaritzburg.
GEOLOGICAL SERIES. 1985. 2732 St Lucia. 1: 250 000 map. Government Printer, Pretoria.
GEOLOGICAL SERIES. 1988. 2730 Vryheid. 1: 250 000 map. Government Printer, Pretoria.
GERMISHUIZEN, G. & FABIAN, A. 1997. Wild flowers of northern South Africa. Fernwood Press,
Cape Town.
GERMISHUIZEN, G. & MEYER, N.L. (Eds). 2003. Plants of southern Africa: an annotated
checklist. Strelitzia 14. NBI, Pretoria.
GERMISHUIZEN, G., MEYER, N.L. STEENKAMP, Y. & KIETH, M. (Eds). 2006. A checklist of South
African plants. SABONET Report no 41. Pretoria
GIBBS RUSSELL, G.E. et al. 1990. Grasses of southern Africa. Memoir of the Botanical Survey of
South Africa 58: 1 – 437.
GOLDING, J. (Ed.). 2002. Southern African Plant Red Data Lists. Southern African Botanical
Diversity Network report no. 14. National Botanical Institute, Pretoria.
GOODMAN, P.S. 1990. Soil, vegetation and large herbivore relations in Mkuzi Game Reserve,
Natal. PhD thesis. University of the Witwatersrand, Johannesburg.
HENDERSON, L. 2001. Alien weeds and invasive plants. Plant Protection Research Institute
Handbook no. 12, Agricultural Research Council, Pretoria.
HENNEKENS, S.M. & SCHAMINEE, J.H.J. 2001. TURBOVEG, A comprehensive database
management system for vegetation data. Journal of Vegetation Science 12: 589591.
HILTON-TAYLOR, C. 1996a. Red Data list of southern African plants. Strelitzia 4: 1 - 117.
HILTON-TAYLOR, C. 1996b. Red Data list of southern African plants. 1. corrections and
Ekotrust CC
44
Thanda Mduna 2012
additions. Bothalia 26: 177 - 182.
HILTON-TAYLOR, C. 1997. Red Data list of southern African plants. 2. corrections and
additions. Bothalia 27: 195 - 209.
KELLERMAN, T.S., COETZER, J.A.W. & NAUDE, T.W. 1988. Plant poisonings and mycotoxicoses
of livestock in southern Africa. Oxford University Press, Cape Town.
KLOPPER, R.R. et al. 2006. Checklist of the flowering plants of Sub-Saharan Africa. An index of
accepted names and synonyms. SA Botanical Diversity Network No. 42. SABONET,
SANBI, Pretoria.
LAND TYPES 1985. Land type map 2730 Vryheid. Government Printer, Pretoria.
LAND TYPES 1986. Land type map 2632 Mkuze. Government Printer, Pretoria.
LOW, A & REBELO, A. 1998. Vegetation of South Africa, Lesotho and Swaziland. Department
of Environmental Affairs & Tourism, Pretoria.
LUBBE, R.A. 1996. Vegetation and flora of the Kosi Bay Coastal Forest Reserve in Maputaland,
northern KwaZulu-Natal, South Africa. MSc dissertation. University of Pretoria, Pretoria.
MANNING, J. 2003. Wildflowers of South Africa. Briza, Pretoria.
MATTHEWS, W.S., VAN WYK, A.E. & VAN ROOYEN, N. 1999. Vegetation of the Sileza Nature
Reserve and neighbouring areas, South Africa, and its importance in conserving the
woody grasslands of the Maputaland Centre of Endemism. Bothalia 29: 151-167.
MATTHEWS, W.S., VAN WYK, A.E., VAN ROOYEN, N. & BOTHA, G.A. 2003. Vegetation of the
Tembe Elephant Park, Maputaland, South Africa. South African Journal of Botany 67:
573-594
MOLL, E.J. 1978. The vegetation of Maputaland - a preliminary report on the plant
communities and their present and future conservation status. Trees in South Africa
29: 31-58.
MUCINA, L. & RUTHERFORD, M.C. 2006. The vegetation of South Africa, Lesotho and
Swaziland. SANBI, Pretoria.
MUCINA, L., RUTHERFORD, M.C. 2006. Vegetation map of South Africa, Swaziland and
Lesotho. SANBI, Pretoria.
NEMA:
BA.
2009.
Draft
national
list
of
threatened
ecosystems.
Notice
1477
of
2009.Government Gazette No 32689. Government Printer.
PODANI, J. 2001. SYN-TAX: Computer programs for data analysis in ecology and systematics.
Scientia Publishing, Boedapest.
RAIMONDO, D. et al. (eds) 2009. Red lists of South African plants. Strelitzia 25. SANBI, Pretoria.
RETIEF, E. & HERMAN, P.P.J. 1997. Plants of the northern provinces of South Africa: keys and
diagnostic characters. Strelitzia 6: 1–681. NBI, Pretoria.
RUTHERFORD, M.C. & WESTFALL, R.H. 1994. Biomes of southern Africa: an objective
categorization. Memoir of the Botanical Survey of South Africa 63. 2nd edition. NBI,
Pretoria.
SCHMIDT, E., LOTTER, M. & McCLELAND, W. 2002. Trees and shrubs of Mpumalanga and
Kruger National Park. Jacana, Johannesburg.
SMIT, N. 1999. Guide to the Acacias of South Africa. Briza, Pretoria. ISBN 1-875093-15-X. CD
ROM available).
SMITH, R. J. 2001. Designing an integrated protected area network for Maputaland, South
Africa. PhD thesis. University of Kent, Canterbury.
VAHRMEIJER, J. 1981. Gifplante van suider-Afrika. Tafelberg Uitgewers, Kaapstad.
Ekotrust CC
45
Thanda Mduna 2012
VAN JAARSVELD, E., VAN WYK, B-E & SMITH, G. 2000. Vetplante van Suid-Afrika. Tafelberg
Uitgewers, Cape Town.
VAN OUDTSHOORN, F. 1999. Guide to grasses of southern Africa. Briza, Pretoria.
VAN ROOYEN, N. & MORGAN, S. 2007. Vegetation types of Phinda and Mkhuze Game
Reserves. Unpublished report to Phinda Game Reserve.
VAN ROOYEN, N. & MORGAN, S. 2007. Vegetation types of Phinda Game Reserve.
Unpublished report to Phinda Game Reserve.
VAN ROOYEN, N. 2004. Vegetation types and wildlife re-establishment in the Greater St Lucia
Wetland Park. Report to GSLWP Authority, KwaZulu-Natal.
VAN ROOYEN, N. 2005. Alien plant strategic management plan for the Zululand region.
Ekotrust CC, Pretoria.
VAN WYK, A.E. & MALAN, S. 1988. Field guide to the wild flowers of the Witwatersrand &
Pretoria areas. Struik, Cape Town.
VAN WYK, A.E. & SMITH, G.F. 1998. Regions of Floristic Endemism in southern Africa. Umdaus
Press, Pretoria.
VAN WYK, A.E. & VAN WYK, P. 1997. Field guide to trees of southern Africa. Struik, Cape
Town.
VAN WYK, B-E & SMITH, G. 1996. Guide to the Aloes of South Africa. Briza, Pretoria.
VAN WYK, B-E, VAN HEERDEN, F., & VAN OUDTSHOORN, B. 2002. Poisonous plants of South
Africa. Briza, Pretoria.
VAN WYK, B-E, VAN OUDTSHOORN, B. & GERICKE, N. 1997. Medicinal plants of South Africa.
Briza, Pretoria.
VAN WYK, B-E. & GERICKE, N. 2000. Peoples Plants. Briza, Pretoria.
VERSFELD, D.B., LE MAITRE, D.C, & CHAPMAN, R.A. 1998. Alien invading plants and water
resources in South Africa: a preliminary assessment. Water Research Commission Report
No TT 99/98. Pretoria: Water Research Commission, Pretoria.
WATT, J.M. & BREYER-BRANDWIJK, M.G. 1962. The medicinal and poisonous plants of southern
and eastern Africa. 2nd ed. Livingstone, London.
WEATHER BUREAU. 1988. Climate of South Africa. WB 40. Government Printer, Pretoria.
WEATHER BUREAU. 1998. Climate of South Africa. Government Printer, Pretoria.
WEIDINGSHANDBOEK. 2007. Kejafa Knowledge Works, Johannesburg.
WHITE, F. 1983. The vegetation of Africa. A descriptive memoir to accompany the
UNESCO/AETFAT/UNSO vegetation map of Africa. UNESCO, Paris.
Ekotrust CC
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Thanda Mduna 2012
APPENDIX A
GPS coordinates for 50 monitoring sample plots on Thanda and Mduna
Monitoring plot nr
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
Ekotrust CC
Vegetation plot
nr
1
2
8
9
27
54
57
102
29
34
41
88
49
60
67
79
80
84
100
33
36
38
39
40
45
64
70
73
101
26
48
75
94
97
78
85
90
91
92
4
76
14
15
22
23
68
69
11
18
19
Coordinates
S27 51 46.3 E32 05 17.4
S27 50 37.6 E32 02 24.6
S27 52 24.1 E32 08 58.4
S27 52 40.9 E32 09 59.6
S27 50 25.6 E32 08 17.9
S27 49 56.7 E32 05 23.8
S27 50 18.4 E32 06 36.4
S27 51 09.0 E32 02 45.8
S27 50 37.3 E32 07 35.2
S27 50 39.9 E32 02 21.3
S27 51 17.6 E32 01 38.8
S27 54 44.9 E32 05 38.0
S27 51 07.7 E32 03 45.2
S27 51 08.4 E32 05 34.0
S27 49 17.7 E31 59 37.4
S27 54 01.9 E32 04 48.3
S27 54 24.0 E32 04 59.7
S27 55 05.0 E32 05 04.5
S27 49 29.9 E32 06 55.5
S27 50 39.7 E32 02 23.5
S27 49 40.7 E32 02 01.9
S27 49 52.8 E32 01 35.8
S27 50 09.9 E32 01 02.9
S27 51 04.8 E32 01 37.0
S27 53 28.0 E32 00 50.3
S27 49 00.0 E32 00 41.8
S27 50 29.8 E31 59 37.7
S27 51 26.8 E32 00 27.2
S27 49 07.5 E32 05 22.5
S27 50 10.7 E32 08 34.6
S27 53 16.3 E32 03 50.6
S27 52 28.6 E32 00 51.5
S27 53 16.4 E32 03 50.2
S27 49 36.1 E32 06 43.4
S27 54 01.7 E32 04 29.9
S27 55 05.5 E32 05 05.6
S27 53 50.9 E32 05 43.6
S27 53 47.5 E32 05 25.6
S27 53 43.5 E32 05 18.7
S27 51 42.6 E32 07 04.8
S27 54 20.2 E32 03 55.0
S27 50 12.3 E32 09 39.8
S27 48 00.3 E32 06 34.8
S27 48 41.4 E32 07 35.8
S27 49 08.6 E32 08 25.5
S27 49 15.3 E31 59 50.3
S27 49 19.8 E31 59 55.5
S27 51 22.6 E32 09 40.8
S27 48 03.7 E32 06 50.6
S27 48 11.4 E32 06 55.0
47
Thanda Mduna 2012
APPENDIX B
List of grass species and their ecological status on Thanda and Mduna
Classes 1 – 5 (see text)
Aristida adscencionis
Aristida bipartita
Aristida congesta subsp. barbicollis
Bare soil
Brachiaria nigropedata
Brachiaria serrata
Cenchrus ciliaris
Chloris virgata
Cymbopogon caesius
Cymbopogon pospischilii
Cymbopogon validus
Cynodon dactylon
Digitaria argyrograpta
Digitaria eriantha
Enneapogon scoparius
Eragrostis curvula
Eragrostis lehmanniana
Eragrostis sp.
Eragrostis superba
Forb
Hyparrhenia filipendula
Hyparrhenia hirta
Ischaemum afrum
Leptochloa eleusine
Melinis repens
Panicum coloratum
Panicum deustum
Panicum maximum
Setaria incrassata
Setaria sphacelata
Sporobolus ioclados
Themeda triandra
Trachypogon spicatus
Trichoneura grandiglumis
Tristachya biseriata
Tristachya leucothrix
Ekotrust CC
5
5
5
0
5
5
1
4
1
4
3
3
3
4
2
1
2
5
5
5
2
3
4
4
2
5
4
3
3
3
3
5
1
1
1
2
2
4
1
4
4
5
4
4
2
48
Thanda Mduna 2012
APPENDIX C
Photographs of 50 sampling site
See attached folder with electronic photographs.
Ekotrust CC
49

Vegetation monitoring - Biodiversity Advisor

Transcription

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