Ecology

Levels of Organization

Biotic and Abiotic Factors

• Biotic factors are the living organisms in an ecosystem

• Abiotic factors are the nonliving conditions or materials in the ecosystemExamples of Biotic Factors Examples of Abiotic Factors

Bison populationHawk populationSnake populationPrairie dog populationGrass population

Stream (water)RocksAir (oxygen, carbon dioxide)LightTemperature

Energy Pyramids

• Only 10% of the energy stored in each trophic level is passed on to the level above