Many factors determine the health of an aquatic ecosystem. which choice lists only abiotic factors?

a) the number of species of algae, fish, and water fowl present in the ecosystem

b) the acidity of the water, the number of species of insects, and the air temperature

c) the oxygen content of the water, the water temperature, and the chemical composition of the bottom mud

d) the amount of sunlight penetrating the water, the phosphorus content of the water, and the number of species of fish

C) the oxygen content of the water, the water temperature, and the chemical composition of the bottom mud.  

An ecosystem is a biotic community, which consists of abiotic and biotic components. The abiotic components includes water, air, sunlight, soil, temperature and weather. The biotic components includes all the living species like plants, animals, microbes and human beings.

The abiotic factors which will determine the health of an aquatic ecosystem are oxygen content of the water, the temperature of the water, and the chemical composition of the bottom mud.

The oxygen is an important gas which is required by all living organisms for respiration. In aquatic ecosystem the atmospheric oxygen gets dissolved with water. Therefore, the aquatic organisms receives oxygen from the water for respiration. Low availability of oxygen, will result in death of living organisms in the aquatic ecosystem.

The temperature of the water, is an important abiotic factor. Some of the aquatic species are not able to survive in the extreme cold and extreme hot water temperatures. Therefore, temperature levels should be suitable for the survival of living species in the aquatic ecosystem.

The chemical composition of the bottom mud is the result of the day to day decomposition activities of the microbes. It consists of organic matter, which allows the transfer of essential nutrients along with the water over the entire water body. Some organisms also, feed upon the bottom bed.