Terrestrial and Aquatic Ecosystem

What is common between a terrestrial and an aquatic ecosystem. Both have similar type of trophic structure. They possess an autotrophic layer concentrated where light is most available, which fixes energy of the sun and manufactures food from inorganic substances. In forests this layer is represented by tree canopies; in grasslands by herbaceous vegetation; and in lakes and seas by the upper layer of water.

Ecosystems also possess a heterotrophic layer that utilises food stored by autotrophs, transfers energy and circulates matter by means of herbivory, predation and decomposition. We shall now discuss the vertical stratification in relation to animal life. The degree of vertical stratification has a pronounced influence on the diversity of animal life in the community. A strong correlation exists between foliage height diversity and bird species diversity. Increased vertical stratification increases the availability of resources and living space, which favours a certain degree of specialisation. Grassland with their two strata, hold about 6 to 7 species of birds, all ground nesters. A deciduous forest may support 30 or more species occupying different strata. Like birds, insects too show similar stratification.