(a) Taking an example of a small pond, explain how the four components of an ecosystem function as a unit.
(b) Name the type of food chain that exists in a pond.

Explanation

The four components of an ecosystem work in the following ways in a pond :
1. Productiyity : This is represented by the autotrophic phytoplanktons some algae and the floating and marginal plants found at the edges .
2. Energy flow : Represented by water in the pond with all the dissolved organic and inorganic substances, the solar energy and other climatic conditions that regulate the rate of function of the pond. The consumers are represented by the 200 planktons and bottom dwelling forms .
3. Decomposition : The decomposers are the fungi bacteria and flagellates abundant at the bottom of the pond.
4. Nutrient cycling : The pond ecosystem converts inorganic material into organic form using solar energy by the autotrophs . The autotrophs are eaten up by heterotophs , decomposition and mineralization of dead matter for reuse by autotrophy is done by decomposers.
(b) The food chain that exists in a pond is a grazing food chain