Biotic Factors: A factor created by a living thing or any living component within an environment in which the action of the organism affects the life of another organism.
Food chains and food webs deal with both matter and energy. When ecologists want to focus only on energy, they use another type of model--an ecological pyramid.
As you move from the bottom of the pyramid there is less and less energy between levels. Producers have the most energy while tertiary consumes have the least amount. This because producers of create their own energy and the other levels can not. Therefore every level depends on one another.
Communities And Biomes:
Communities:
Succession:the progressive replacement of one community by another until a climax community is established.
Primary Succession:the series of changes that occur in an area where no soil or organisms exist
Secondary Succesion:the series of changes that occur in an area where the ecosystem has been disturbed, but where soil and organisms still exist.
Climax Community:a stable community that no longer goes through major ecological changes.
Succession
Primary and secondary succession differ because primary successsion happens in an are where there isn't any life present and secondary happens in an area where some life still exists.
Biomes:
Aquatic Biomes
ApproxImately 75% of Earth's surface is covered with water.