Ecosystem productivity

The productivity of ecosystem refers to the rate of growth of energy or organic matter per unit time by auto trophies at tropic level one through the process of photosynthesis with the help of solar energy. In other words, ecosystem productivity represents the total amount of energy fixed or stored by the auto trophies per unit time in the ecosystem. The production of organic matter by auto trophies is known as primary production and the green plants involved in the production activity are called as primary producers. The ecosystem productivity depends on two factors the availability of the amount of solar radiation to the primary producers at tropic level one and the efficiency of the plants to convert solar energy into chemical energy which is used by the green plants to build up their tissues.  Primary production can be measured in two ways Gross primary production is the total amount of energy produced by the auto trophies at tropic level and Net primary production represents the amount of energy or organic matter fixed or stored at tropic level one. Thus net primary production excludes the amount of energy which is lost through respiration by the gross primary production minus the energy lost by respiration. The ecosystem productivity whether Gross or net is generally measured in gram/meter square/day or year.

Since the primary productivity of a natural ecosystem largely depends on the amount of solar radiation, there is positive correlation between primary productivity and solar radiation system. There is marked decrease in solar radiation received at the earth’s surface from equator towards the poles, primary productivity also, on an average decreases markedly towards the poles. Very large scale the primary productivity of the terrestrial ecosystems is far more than the marine ecosystems.