Organisms at a higher trophic level have | Class 12 Biology Chapter Ecosystem, Ecosystem NCERT Solutions

The sun is the ultimate source of the energy for all the ecosystem. Photosynthetic organisms converts solar energy to chemical energy but in this the total amount of energy does not change. In ecosystem energy flows unidirectionally. Higher amount of energy is present at the producer level in the food chain; they carry out respiration process in which they break down some organic compounds in their bodies to release chemical energy. Some power of the chemical energy is used to make ATP for the energy and some portion is concerted to heat which cannot be used. As the chemical energy passes from one trophic level to next then there is a gradual decrease in the amount of energy at each next trophic level, i.e., the 10 times at next trophic level. At the last trophic level there will be far less amount of energy available.

As the transfer of energy follows the Lindeman’s 10% law, he states that during the transfer of food energy from trophic level to the other, only 10% of the energy is stored from the lower trophic level and the remaining 90% lost in respiration, decomposition.

Diagram of Flow of Energy through an Ecosystem: