Give an account of energy flow in an ecosystem.
Solution and Explanation
Energy enters an ecosystem from the sun. Solar radiation passes through the atmosphere and are absorbed by the Earth's surface. These radiations help plants in carrying out the process of photosynthesis. Also they help maintain the Earth's temperature for the survival of living organisms. Some solar radiations are reflected by the Earth's surface.
Only 2-10 percent of solar energy is captured by green plants(producers)during photosynthesis to be converted into food. The rate at which biomass is produced by plants during photosynthesis is termed as 'gross primary productivity'. When these green plants are consumed by herbivores only 10% of the stored energy from producers is transferred to herbivores. The remaining 90% of this energy is used by plants for various processes such as respiration growth and reproduction.
Similarly only 10% of the energy of herbivores is transferred to carnivores. This is known as the ten percent law of energy flow.
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Concepts Used:
Ecosystem
An ecosystem is a structural and functional unit of ecology where the living organisms come in to interact with each other and the surrounding environment.
Structure of the Ecosystem:
The structure of an ecosystem is distinguished by the organization of both biotic and abiotic components. This involves the distribution of energy in our environment. It also comprises the climatic conditions prevailing in that particular environment.
There are two main components of the structure of an ecosystem, namely:
- Biotic Components
- Abiotic Components
The biotic and abiotic components are interconnected in an ecosystem. It is an open system where the energy and components can flow through the boundaries.