Chapter 14 Ecosystem
- An ecosystem is a functional unit of nature and comprises abiotic and biotic components.
- Abiotic components are inorganic materials like air, water and soil whereas biotic components are producers, consumers and decomposers.
- Four important components of an ecosystem:
- Productivity
- Decomposition
- Energy flow
- Nutrient cycling
- Primary productivity is the rate of capture of solar energy or biomass production of the producers. Secondary productivity is the rate of assimilation of food energy by the consumers.
- Decomposition involves three processes:
- Fragmentation of detritus
- Leaching
- Catabolism
- Energy flow is unidirectional. First, plants capture solar energy and then, food is transferred from the producers to the decomposers.
- The storage and movement of nutrient elements through the various components of the ecosystem is called nutrient cycling. Nutrient cycling is of two types:
- Gaseous
- Sedimentary
- The biotic community is dynamic and undergoes changes with the passage of time. These changes are sequentially ordered and constitute ecological succession.