- 1 Environment
- 2 Ecosystem and its components
- 3 Types of Ecosystems
- 4 Components of Ecosystem
- 5 Example of an Ecosystem
Ecosystem and its components
An ecosystem may be defined as a structural and functional unit of the biosphere comprising living organisms and their non- living environment that interact by means of food chains and chemical cycles resulting in energy-flow, biotic diversity and material cycling to form a stable, self-supporting system.
Types of Ecosystems
(1) Natural ecosystems: These ecosystems operate in the nature by themselves without any human interference.Examples of natural ecosystems are a pond, a lake, a meadow, a desert, a grassland, a forest, an ocean etc.
(2) Artificial ecosystems: These are maintained by man and hence are also termed man-made or man-engineered ecosystems. In these ecosystems, man maintains/disturbs the natural balance by the addition of energy and planned manipulations. Examples of artificial ecosystems are croplands, orchards, gardens, aquarium etc.
1. Temporary ecosystems
(1) Temporary ecosystems: These are short-lived ecosystems which may be natural or man-made.
Examples : Rainfed pond and laboratory culture of protozoans.
(2) Permanent ecosystems: These are self-supporting natural ecosystems that maintain themselves for relatively long duration.
Examples : a lake, a forest, a desert etc.
On the basis of size, ecosystems may be classified as:
1. Small ecosystems
(1) Small ecosystems: Small-sized ecosystems are also termed microecosystems.
Example : a flowerpot, water in a dish, a site under a stone etc.
(2) Large ecosystems: Very large-sized ecosystems are also termed macro-ecosystems, e.g., an ocean, a forest, a desert etc.
Components of Ecosystem
A. Abiotic (non-living) components
(A) Abiotic (non-living) components
Abiotic factors include :
(1) Inorganic substances
(1) Inorganic substances
(2) Organic compounds
(3) Climatic factors
(B) Biotic (living) components
The macroconsumers are of following types :
(a) Primary or first-order consumers: These include the animals which eat plants or plant products. They are called herbivores.
(b) Secondary or second order consumers: These include the animals which feed on herbivores. They are called carnivores. Cats, dogs, foxes etc. are secondary consumers in the terrestrial ecosystems, and water bugs, water beetles, frogs, small fish etc. are secondary consumers in the aquatic ecosystems.
(c) Tertiary or third order consumers: These are larger carnivores which feed on secondary
(d) Quaternary or fourth order consumers: These are the largest carnivores which feed on tertiary consumers. They are not eaten by other animals and are also called top carnivores. Tigers and lions are examples in land ecosystems and dolphins and whales are examples in aquatic ecosystems.
(3) Decomposers (reducers)
The decomposers degrade dead remains of plants and animals and waste organic matter into
(a) simple small organic molecules which they utilise themselves, and
(b) inorganic substances that are released into the environment for reuse as raw materials by the producers. The decomposers are also called saprotrophs.
Example of an Ecosystem
(2) Animals such as frogs, insects and birds. All these are consumers. All these living organisms interact with each other and their growth, reproduction and other activities are influenced by the abiotic components of ecosystem.
(3) Decomposers are microorganisms present in the soil. These provide raw materials back to the environment, by decomposition of dead, decaying matter, for their reuse by the producers.