Question

define the terms interdependence and eutrophication. Explain how the organisms (biotic factors) are involved with the environment (abiotic factors) for interdependence and eutrophication

Answer 1

Welcome @jese ,
You can think eutrophication as aging of a river. In a young lake the water is cold and clear, supporting little life. With time, streams draining into the lake introduce nutrients such as nitrogen and phosphorus, which encourages the growth and decay of aquatic plant, simple algae and plankton are favoured over other more complicated plants. Now as the fertility increases plant and some animal life burgeons, and organic remains begin to deposited on the lake bottom. Over centuries, as silt and organic debris pile up, the lake grows shallower and warmer. Gradually the initial river gets converted into marshy area followed by land.

Natural and controlled eutrophication is benificial for life while human caused and accelerated eutrophication such as due to discharge of untreated sewage has adverse effect on aquatic fauna. In this case, eutrophication increases the growth of aquatic flora rapidly which depletes the oxygen levels very quickly and hence aquatic animals start dying.