Transcript Communities & Biomes

Communities & Biomes
Limiting Factor
Any biotic or abiotic factor that
restricts the existence, numbers,
reproduction, or distribution of
organisms
Examples of limiting factors
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Availability of food & water
Predation
Temperature – timberline
Sunlight
Climate
Space
Cascade Mountain
Tolerance
The ability of organisms to
withstand fluctuations in biotic and
abiotic factors
Timberline on Mount Shasta
Succession
• The orderly, natural changes and
species replacements that take place
over time
• e.g. abandoned parking lot over 30
years
Types of Succession
• Primary
• Secondary
Primary Succession
• The colonization of barren land
(no living organisms exist there) by
pioneer species
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Due to:
*Fire
*Flood
*Volcano
Primary Succession
• Pioneer species (Lichens & mosses)
break up rock into soil
• Ferns & weeds further break up soil
• Seeds are carried by animals or
blown by the wind
Secondary Succession
• The sequence of changes that takes
place after an existing community is
severely disrupted in some way (fire,
flood, etc…)
• PREVIOUS LIVING ORGANISMS
AND SOIL ARE PRESENT
Climax community
• A stable, mature community that
undergoes little or no change in species
• a.
Can last hundreds of years
• b.
Climax communities occur quicker
through secondary succession because soil
is already formed (primary succession
takes longer due to soil formation)
Biomes
TheTerrestrial Biomes
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Tropical Rainforest
Tropical Dry Forest
Tropical Savanna
Temperate Grassland
Desert
Temperate Woodland & Shrubland
Temperate Deciduous Forest
Temperate Coniferous Forest
Temperate Rainforest
Taiga
Tundra
The Aquatic Biomes
• Freshwater
• Estuaries
• Marine
• Aquatic Biomes are determined by
depth, flow, temperature, &
chemistry of the overlying water
Freshwater Biomes
Flowing water
Rivers & streams
Standing water
Lakes & ponds
Wetlands*
Bogs, marshes, swamps
*Water covers the soil for part of the year
Estuaries
• Salt-marshes & mangrove swamps
• Form where fresh & salt water mix
• Called brackish water
Marine
Zonation of water by depth
1. Photic zone – light can penetrate
2. Aphotic zone – light DOES NOT reach
3. Benthic zone – ocean floor
Zonation of water by distance from the shore
1. Intertidal zone
2. Coastal (Neritic) zone
3. Open ocean