BIO1042 Lecture Notes - Lecture 5: Deep Sea, Ecological Pyramid, Estuary
8 Aug 2018
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Document Summary
An ecosystem consists of all the organisms living in a community, as well as the abiotic factors with which they interact. Ecosystems range from a microcosm, such as an aquarium, to a large area such as a lake or f orest. Macquarie island ecosystem consists of: the plant community, the animal community, physical factors with which these organisms interact, energy flows & chemical cycling. The basis of nearly all food webs: autotrophs, plants in terrestrial systems, algae in marine systems. A (cid:374)o(cid:374) solar source of energy: deep sea thermal vents; lithotrophic bacteria that derive energy directly from rocks. The first law of thermodynamics (cid:858)e(cid:374)ergy cannot be created or destroyed, only tra(cid:374)sfor(cid:373)ed(cid:859) = changed from one form to another energy flows. Matter cycles: the total energy of an isolated system is constant, although within that system, energy may change its form. Second law of thermodynamics = every exchange of energy increases the entropy of the universe.
