Ecosystem Connections: who, what, where, when Remember



Ecosystem Connections: who, what, where, when Remember
who, what, where, when
Remember biomes?
What’s the connection?
First, some definitions:
Population = one species in a given
area and time
Community = different species
within a given area
Ecosystem = communities together
with their environment
Population = individuals of same species
who tend to mate with each other in a limited
geographic area
Some individuals of the same species
(Canada geese, Branta canadensis) at
Spring Valley Wildlife Preserve
Community = interacting populations of
different species within a given area
A few spp. in Spring Valley Wildlife Preserve
Ecosystem = communities together with
their environment, functioning as a unit
And one more:
Biome = the world's major communities, classified
according to predominant vegetation and
characterized by adaptations of organisms to that
particular environment (Campbell)
Some biomes we’ll consider this year … from deserts to
oceans, and temperate forests to freshwater streams …
Dr. Cummins
Dr. Myers
from tropical forests to grasslands to the dirt beneath them
Dr. Cummins
(in the mangroves!)
Grassland pic
Dr. McCollum
So what determines where
biomes, ecosystems,
communities and
populations occur?
Geologic processes --> habitat
Water, dirt, rock, ice or deep sea vent?
Earth’s position in space --> solar insolation
Climate, seasons, latitudinal and elevation
Evolution / adaptive radiation --> species
and their adaptations
Who got there first and what selective pressures
have they faced?
And today’s
BIG question …
how are these very
different biomes,
communities and
populations connected?
First task:
Write down as many
ways as you can that
connections could exist
from one “level” to
Also consider different
definitions of connection
(or connectivity)
Migratory connectivity
How “in touch” are populations on their annual winter
versus summer habitats?
Landscape connectivity
How close together are habitat patches, and what
habitats lie in the matrix between them?
Fisheries connectivity ?
Where do larval fish move to, and when/where do
they return for breeding? (2 rounds of migration?)
So how many of these
did you come up with?
“Process” connections - flow of:
Individuals and/or populations of individuals
“Geographic” connections
Moving water
Estuaries, mangroves, lagoons, etc.
All kinds of “edges”!
So how many more did
you come up with???
So, let’s take a closer look
at connections
Individuals …
Migrate (seasonal)
Find new territories
Take advantage of
newly formed habitat
Spread randomly - on
the wind, with storms,
with floods, carried by
!They carry with them
… genetic diversity
Populations, also …
Migrate (seasonal)
Find new territories
Take advantage of
newly formed habitat
Serious implications
for genetic diversity
How do populations
keep from becoming
Key population ecology
Population structure
Reproductive rate
Genetic variability
Research questions about
What’s the survivorship for migrating birds?
What affects them in their winter and
summer habitats?
How does their ability to find suitable habitat
along the way affect survivorship?
How do they find their way?
Are they temperate species adapted to the
tropics or vice versa?
What is the age structure of the population?
How do they cope with predation?
And many more ….!!
Communities …
Most connections
are within the
community, not all
Move nutrients
among community
Serve as sources or
Sink sinks for other
poor habitat
Source = reproduction
high enough to supply
Sink = reproduction
below replacement level
Sink invasive sp.
Key community
ecology concepts
Food chains and webs
Spp. richness (#) versus
spp. diversity (# plus
Genetic versus species
Species interactions
Predation to mutualism
Direct versus indirect
Ecological niches
Coevolution of species
Island biogeography
Research questions about
What is the trophic structure (food web)?
How do species within the community
partition resources?
Is biodiversity homogeneous throughout the
community / habitat?
What selective pressures encouraged the
development of thorns, defensive chemicals,
and large, hard seeds?
And again, so many more ….!!
Ecosystems … are ALL ABOUT connections
Movement of inorganic nutrients and other
molecules, organic energy and waste products,
water, air, and organisms themselves from one
reservoir to another is THE topic.
Key ecosystem ecology concepts
Primary production
How much? Where? What limits?
Nutrient cycling
Reservoirs and what moves in and out of them (fluxes)
Habitat heterogeneity
Source/sink populations
Connectivity between patches
Research questions about
How do organic and inorganic nutrients flow
through ecosystems?
How are humans impacting these flows?
How do inputs into a reservoir react?
Does the effect change with increasing
concentration? Duration? Consistency?
How does biodiversity change across and
between ecosystems?
And many more ….!!
And finally, what
connections could possibly
exist among biomes?
Biomes are connected by …
Dust to greenhouse
Streams and rivers
Nutrient flows
landscapes or
Key biome concepts
Research questions about
and within biomes …
To be continued ….
Through the next several weeks!
A key point … many topics
cross disciplinary boundaries
Species interactions
Landscape ecology
- patches, corridors
and “the matrix”
“the devil is in the
And my favorite
quote about science
“we stand on the
shoulders of giants”
Scientists build on
what is already

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