Transcript Ecology
Ecology Ecology • Ecology is the study of the interactions among organisms and their environment What is the Biosphere? • The portion of the earth in which all living things exist • Only about 20Km of total diameter of earth • From ocean floor to about 8Km above earths surface Two types of factors in Biosphere • Biotic: all things living –Examples? • Abiotic: all things non-living –Examples? Many subcategories • Population: all individuals of a certain species within a certain area • Community: all the populations of different species within an area Many subcategories • Ecosystem: includes a community and its physical environment –Includes both biotic and abiotic Individuals have a habitat and a niche • Habitat: where an individual organism lives; its home – where is yours? • Niche: the role that organism plays in its ecosystem –What is yours? Relationships between organisms • Competition: if two individuals occupy the same niche they will compete –Limited resources like? –Only one will win Relationships between organisms • Symbiosis: two organisms living in close association –Three types: mutualism, commensalism and parasitism Relationships between organisms Mutualism: both species benefit Example? Why? Relationships between organisms Commensalism: one benefits; the other is neither hurt nor helped Relationships between organisms Parasitism: one species benefits at the other’s expense All organisms require Energy • As one organism eats another energy moves through ecosystem • Forms food chain • Many food chains make food web Energy Pyramid Energy Pyramid • Producers/Autotrophs: make food from sunlight or other inorganic molecules – examples: plants, algae and bacteria Energy Pyramid • Primary consumers: eat producers –Herbivores –Examples: rabbits, plankton Energy Pyramid • Secondary or High order consumers: eat primary consumers carnivores –Larger animals –Top consumers are not eaten by anyone Where do they go then? • Decomposers: bacteria; break down dead organisms and return nutrients (nitrogen) back to the soil for producers to use Food Chain Food Web Mother Nature Recycles All essential inorganic nutrients cycle between biotic and abiotic parts of ecosystem - Water - Oxygen - Carbon - Phosphorus - Nitrogen Water Cycle Water Cycle • Organisms give off water • Water evaporates into atmosphere • Water condenses in cloud • Falls back to earth in rain/snow • Taken back in by Organisms Carbon cycle Nitrogen Cycle Phosphorous Cycle Oxygen Cycle