ECOSYSTEM- AND ITS COMPONENTS
The physical and biological world where we live is called our environment
A community of organisms that interact with one another and with the environment is called an ecosystem.
- An ecosystem is a self-contained unit of living things (plants, animals, and decomposers), and their nonliving environment (soil, air, and water).
- Examples of ecosystems are a grassland (meadow); a forest; a desert; a mountain; a pond; a lake; a river; and a sea.
COMPONENTS OF AN ECOSYSTEM
- An ecosystem has two types of components, viz. biotic component and abiotic component.
- Abiotic components mean non-living components and biotic components mean living components.
- Thus, we can now say that an ecosystem consists of a non-living environment and the living biological community.
- All the non-living things make the abiotic component of an ecosystem.
- Air, water and soil are the abiotic components.
- Air provides oxygen (for respiration), carbon dioxide (for photosynthesis) and other gases for various needs of the living beings.
- Water is essential for all living beings because all the metabolic activities happen in the presence of water.
- Soil is the reservoir of various nutrients which are utilised by plants. Through plants, these nutrients reach other living beings.
- The physical factors or climatic factors like light, temperature, pressure and humidity are also considered abiotic components of the ecosystem.
- All living beings make the biotic component of an ecosystem.
- Green plants play the role of producers; because they prepare the food by photosynthesis.
- Animals and other living beings play the role of consumers; because they take food (directly or indirectly) from plants.
- Bacteria and fungi play the role of decomposers; as they decompose dead remains of plants and animals so that raw materials of organisms can be channelized back to the environment.
The biotic community (or living community) of an ecosystem includes three types of organisms.
1. Producer organisms (or Autotrophs) which synthesize their own food.
- All the green plants are producers.
2. Consumer organisms (or Heterotrophs) which are dependent on others for food.
- All animals are consumers.
3. Decomposer organisms (or Saprotrophs) which consume the dead remains of other organisms.
- Certain bacteria and fungi are decomposers.
Important Questions from What We have learned on the Ecosystem.
- What is the functional unit of the environment comprising of the living and non-living components called?
- . Name two natural ecosystems and two artificial ecosystems.
- . Which one of the following is not a terrestrial ecosystem?
Forest, Grassland, Aquarium, Desert
2. Natural ecosystem: Ocean, Forest, lentic and dessert ecosystem. Artificial ecosystem: Farm and Aquarium ecosystem.