Transcript Communities and Biomes

Communities and Biomes
Limiting factors
Any biotic or abiotic factor that
restricts the existence, numbers,
reproduction, or distribution of
organisms.
(examples - food availability, predation,
climate, disease, temperature, etc.)
Succession: Changes over time
What would your backyard look like if you didn’t
mow it or do anything to it? What would it look
like in 5 years? 10 years? 20 years?
First, grass gets taller and weeds grow...
Then, bushes start growing, trees appear…
Later, animals move in and everything grows…
Years later, the area is a forest!
Ecologists refer to the orderly,
natural changes and species
replacements that take place in
the communities of an ecosystem
as succession.
Primary Succession colonization of new sites by
communities of organisms
Lava destroyed everything
in this area. When it
cooled, it formed new land.
The first species in this area
is called a pioneer species.
Secondary succession - the sequence of
community changes that occurs after the
community is disrupted by natural
disaster or human actions.
There was a fire here several
years ago. Several species are
starting to grow back.
The difference between primary and
secondary succession...
Secondary succession occurs in areas that
previously contained life and soil.
In primary succession, everything is new,
including the land and soil.
A climax community is a stable,
mature community that
undergoes little or no change.
Biomes - a large group of
ecosystems that share the same type
of climax community.
Biomes on land - terrestrial biomes
Biomes in salt water - marine biomes
Biomes in fresh water - freshwater biomes
Marine Biomes
Estuary - where salt
and freshwater mix
(brackish water)
Intertidal zone portion of the shoreline
between high and low
tides
Freshwater Biomes
Ponds, lakes,
streams, or
rivers
Terrestrial Biomes
There are many
examples,
including NC’s
very own biome…
Temperate
deciduous forest
Desert - dry region with very little rainfall
Tropical Rain Forest - warm
temperatures, wet weather, many plants and animals
Tundra - treeless land with frozen
ground called permafrost
Taiga – (also called boreal forest)
northern coniferous forest containing
mostly firs, hemlock, and spruce trees
Grasslands
They are called different things in different places:
Australia, Canada, US - prairies
Russia - steppes
Africa - savannas
Argentina - pampas