communities & biomes
DESCRIPTION
Communities & Biomes. Limiting Factor. Any biotic or abiotic factor that restricts the existence, numbers, reproduction, or distribution of organisms. Examples of limiting factors. A. Availability of food & water B. Predation C. Temperature – timberline D. Sunlight - PowerPoint PPT PresentationTRANSCRIPT
Communities & Biomes
Limiting Factor Any biotic or abiotic factor that
restricts the existence, numbers, reproduction, or distribution of organisms
Examples of limiting factors
• A. Availability of food & water• B. Predation• C. Temperature – timberline• D. Sunlight• E. Climate• F. 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
• 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• 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 BiomesFlowing waterRivers & streams
Standing waterLakes & 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
MarineZonation of water by depth1. Photic zone – light can penetrate2. Aphotic zone – light DOES NOT reach3. Benthic zone – ocean floor
Zonation of water by distance from the shore1. Intertidal zone2. Coastal (Neritic) zone3. Open ocean