Energy flow in ecosystem:
1. During the ecological energetics we can study quantity of solar energy, reaching to the ecosystem, and quantity of energy, used by green plants for photosynthesis and finally the quantity and path of energy flow from
producers to consumers.
2. Of the total sunlight reaching to the earth’s about 34% of the sunlight is reflected back, 10% is held by ozone layer, water vapour and other atmospheric gases and 56% reaches to
earth’s surface and only a fraction i.e. 0.02% is used for photosynthesis.
3. In the ecosystem the energy flow is
unidirectional to understand this process
better, we have to consider following thing.
i) The efficiency of the producers in
absorption and conversion of solar energy as well as use of this converted energy by the consumers,
ii) The total input of energy in form of food and its efficiency of assimilation,
iii) The loss through respiration, heat,
excretion etc and the gross net production.
4. There is unidirectional flow of energy as the energy captured by autotrophs does not go back to the solar input or the energy which passes to herbivores does not go back to autotrophs.
5. As the energy flows progressively through various trophic levels it is no longer available to the previous trophic level.
6. As the energy passes form one to the next trophic level it goes on decreasing this is because of the energy dissipated (degraded as heat during various metabolic activities of the organisms.
7. It is measured as respiration coupled with unutilized energy.
8. ln any ecosystem the energy flows from
producers who capture and convert it from
the radiant solar energy to primary- secondary- tertiary consumers.
9. Does the shorter the food chain, greater would be the available food energy and as the length of food chain increases there is corresponding more loss of energy.