Communities and Biomes

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Chapter 4

• Communities and Biomes

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Community Distribution
Limiting Factor any biotic or abiotic factor
that restricts an organism (ex. Food, water,
shelter..)
Range of tolerance when organism receives
too much or too little of something (ex. Sun,
water...)
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• 1. What happened to the deer population over the
  years?
• 2. What are possible reasons for what happened to
  the deer population?
• 3. What do animals need to survive?
• 4. Define limiting factor.
• 5. What are some of the limiting factors that
  affect the deers survival?
• 6. Are wildlife populations static, or do they
  tend to fluctuate as part of an overall balance
  of nature?
• 7. Is nature ever really in balance, or are
  ecological systems constantly changing?

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Succession orderly, natural changes in a
community over time
Pioneer species first inhabiters of an area
(moss, lichens)
Primary (1?) Succession - first colonization of a
new land (lava flow, stream deposit, strip mine)
Climax community a stable mature community that
undergoes little or no succession (example a
mature Oak Forest)
Secondary (2?) succession - sequence of changes
that happen after a community is disrupted by
natural disasters (forest fire, hurricane, flood)
or by human actions (agriculture, clear cutting
forest)
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Biomes a large group of ecosystems that share
the same type of climax community
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Aquatic biome biome of water (river, lake,
ocean, stream)
Marine biome the ocean covers nearly 75 of the
earths surface
Photic zone layer of the water that is shallow
enough that light can pass through
Plankton producers of the ocean, generally
microscopic
Aphotic zone layer of water that is deep enough
that it never receives light
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Marine Zones
Photic
Aphotic
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Estuary water (such as at the mouth of a river)
where fresh water and salt water mix (brackish
water) Estuaries are often associated with high
rates of biological productivity.
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Tidal zone (intertidal zone) is where the land
and sea meet, between the high and low tide
zones. This complex marine ecosystem is found
along coastlines worldwide. It is rich in
nutrients and oxygen and is home to a variety of
organisms
Much of this inhospitable environment is washed
by the tides each day, so organisms that live
here are adapted to huge daily changes in
moisture, temperature, turbulence (from the
water), and salinity.
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Freshwater biome a water biome that does not
contain much salt lakes, ponds, rivers
Most livings are near the surface of fresh water
where the water stays warmer and the light is
able to penetrate the water
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Terrestrial biome biome on land
Two major factors influence the type of biome
that exist on land
        Temperature
        Precipitation
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Biome Graph Precipitation vs Temp.
"Original" Whittaker diagram
"Modified" Whittaker diagram
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NOTE Use original diagram
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Terrestrial Biome Map
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Tundra
Tundra treeless land with long summer days and
below 0?C much of the year.
Permafrost because of the cold temperatures the
ground never thaws more than a few inches deep
the layer under the thawed layer remains frozen
year round (permanently frozen)
People have found remains of even extinct animals
in the permafrost (a woolly mammoth)
It has poor soil due to the weather and small
plants and animals because of the lack of
protection and short growing seasons
10 000-year-old baby mammoth has been unearthed
in a remote northern Siberian region
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Taiga
Taiga (Northern Coniferous Forest) water logged
soil, it lacks permafrost and has acidic soil due
to pine needles. There is more shelter (trees)
and large plants which allows for larger animals
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Desert
Desert Annual rainfall 0 to 25cm. Plants vary
with the amount of rain from small shrubs to
nothing at all. Most animals are small and
remain under cover during the day to escape the
hot sun.
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Grasslands
Grassland 25 to 75 cm of rain annually. It is
covered with grasses and small plants. There is
more biodiversity than deserts because of the
more water. It is ideal for growing grains in the
rich soil.
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Temperate Forest
Temperate forests 70 to 150 cm per year.
Usually there is a rich top layer of soil and a
deeper layer of clay. Plants include broad-leaf
trees. Many animals live in the forest year round
others migrate south. You live here!!!
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Tropical Rain Forest
Tropical Rain Forest Receives 200 to 400 cm of
rain per year. Most nutrients are tied up in the
living material. The roots are usually shallow
because of the thin, poor soil. This is the most
biologically diverse of all the biomes