Mumbai University > First year Engineering > Sem 1 > Environmental Studies

Marks: 5 M

Year: May 2014

Light is the initial energy source for almost all ecological communities. Light is captured by producers (e.g. plants) that convert it into energy rich sugar by a process called photosynthesis.

• The energy captured by plants is later transferred to herbivores or decomposers.
• The energy captured by herbivores is later transferred to carnivores or decomposers.
• The energy captured by carnivores is transferred to other carnivores or decomposers.
• The energy captured by decomposers is transferred to consumers or other decomposers.
• When the organic material produced by plants is consumed by herbivores, only about 10% of the energy is released from the sugars and useable for metabolism. The other 90% is lost as either heat energy through cell respiration or as indigestible waste. A similar gain-loss relationship exists at each succeeding level of a food chain. Therefore, the flow of energy through trophic levels can be represented as a pyramid of energy.