Limiting Factors and Succession

Limiting factor Any biotic or abiotic factor that restricts the existence, numbers, reproduction or distributing of an organism is considered a limiting factor. These factors will both directly and indirectly affect populations. What are some limiting factors?

Common limiting factors: Sunlight Climate Temperature Water Nutrients/food Fire Soil chemistry Space Other organisms

Tolerance The ability of an organism to withstand fluctuations in biotic and abiotic environmental factors is known as tolerance. The limits of an organism's tolerance are reached when the organism receives too much or too little of some environmental factor. When this happens populations shrink.

Succession Ecologists refer to the orderly, natural changes and species replacements that take place in the communities of an ecosystem as succession. It occurs in stages, and during each stage different species of pants and animals may be present due to changing conditions. Usually takes decades or even centuries for one community to succeed another. There are two types of succession: primary and secondary

Primary Succession The colonization of barren land is called primary succession. Ex Lava flow creating new rocks Pioneer species are the first organism to inhabit an area. They can withstand harsh environments. They turn the new rock into soil. Ex lichen, moss Climax community occur after the pioneer species have faded and given rise to new organism. There is little to no change in a climax community Stability does not mean changes stops, however in a climax community the changes are balanced (deaths = births)

Secondary Succession Takes place after a disruption of some type (natural or manmade) occurs to a pre-established climax community. This means that the pioneer species are going to be things more complex such a wild flowers instead of things like moss and lichen. Because soil is already present it usually takes place much faster than primary sucession