Every organism is in perfect balance with its environment. The environment or the surrounding directly or indirectly influences the life and development of organism. The organism and the physical features of the habitat from an ecological complex which is called “Ecosystem”.
Components of Eco-System:
(I) Abiotic components :
The Abiotic components include the Sun rays, Hydrogen, Carbon, Nitrogen, Oxygen, Sulphur, Phosphorus and other elements and various meals are essential for existence of life. The organic compounds like Proteins, Carbohydrates and other biological compounds, which are presented in the biomass and released to the environment.Climate includes Light, Heat, and Temperature, Wind, Humidity, Rainfall, Snow fall etc. and their daily and seasonal fluctuations. The soil includes its composition, structure and properties.
(II) Biotic components:
Include all living organisms present in the environment system and from nutrition point of view it is divided into two classes –
(i) Autotrophic components
(ii) Heterotrophic components;
The autotrophic components include all green plants which fix the radiant energy of sun and prepare food from inorganic substances.
The heterotrophic components include non-green plants and all animals which take food from autotrophy.
The biotic components of an ecosystem can be described as – (I) producers (II) consumers and (III) decomposers or reducers and transformers.
Producers are Autotrophs in which auto means self and trophs means nourishing. The green plants prepare food by using radiant energy and transform them to chemical energy. Plants not only prepare food for themselves, but also they from source of energy for the non-producers too.
(Heterotroph) – the living components which consume food synthesized by the producers are consumers.
The consumers that feed directly on green plants are primary consumers and they graze grasses such as goat, cow, rabbit etc. The second type of consumers are flesh eating animals such as crow, dog, eat, snake etc. There are some other flesh eating animals which prey upon other flesh eating animals such as lion, tiger etc.
The other types of consumers are parasites, scavengers and saprobes. The parasitic plants and animals utilize the living tissues’ of different plants and animals. The scavengers and saprobes utilize dead animals and plants as their food.
(III) Decomposers and transformers:
Decomposers and transformers are the living components of the ecosystem and they are fungi and bacteria. Decomposers attack the dead remains of producers and consumers and degrade the complex organic substances into simper compounds. The simple organic matters are then attacked by another kind of bacteria, transformers, which changes these organic compounds into the inorganic forms that are suitable for re-use by, producers or green plants. The decomposers and transformers play very important role in maintaining the dynamic nature of ecosystems.
Functions of Ecosystem:
The ecosystem plays the following functions such as- (1) Biodiversity (2) Productivity (primary and secondary) (3) food chains and food web (4) Energy flow (5) Material cycling (6) Balance of nature (7) succession and evolution of ecosystem.
Biodiversity include taxonomical, ecological, genetic, biochemical diversities. It is a renewable resource for man and provides food, fodder, fiber, raw-materials that main requires for everyday living. Now-a-day biodiversity is declining due to habit clearance, pollution, biological invasions and changes brought into the biosphere due to many other reasons.
The rate of food production over unit time on a unit area basis is called primary productivity. The total amounts solar energy converted to chemical energy by green plants is called gross primary production (GPP). Maximum GPP occurs in a forest. The net quantity of energy transferred and stored in somatic and reproductive tissues of heterotrophy over period of time is known as secondary productivity and it depends on the amount of primary production in the ecosystem.
(3) Food chain and food webs:
The sequence of organisms which feed on one other from a food chain and each level is termed as a strophic level. Apart from food, toxic substances can also move from a plant to man, either directly or through herbivores and carnivores and carnivores, a food chain signifies feeding relationship in nature passage of nutrients from one organisms to another and flow of energy in ecosystem, the biodiversity, food chains are interwoven to from a food web and these food webs help different organism to survive and reproduce in nature and thus maintain biodiversity.
(4) Energy flow in ecosystem:
The solar energy is the source of energy for biological world and it is converted into chemical energy by the plants and stores as food. This food energy, from the plants food-chains and food-webs. During this process a lot of energy dissipates as heat energy into the environment. Thus an organism sitting at the top of the food chain gets less energy.
(5) Material cycling:
The biotic components are necessary for the growth and development and the elements move in a cyclic manner from Abiotic to biotic and back to Abiotic components of ecosystem. The cycling materials include Water cycle, Gaseous cycle and Sedimentary cycle. The Gaseous cycles are Carbon, Nitrogen arid Oxygen and Sedimentary cycle. The Gaseous cycles are Carbone, Nitrogen arid Oxygen and Sedimentary cycle are Phosphorous and Sulphur.
Thus in any ecosystem we have the following functional components.
(i) Inorganic constituents (air, water and mineral salts)
(ii) Organisms (plants, animals, and microbes)
(iii) Energy input which enters from outside (the sun).
These three interact and for men environmental system. Inorganic constituents are synthesized into organic structures by the green plants (primary producers) through photosynthesis and solar energy is utilized in the process. Green plants become the source of energy for renewals (herbivores) which is turn become source of energy for the flash eating animals (carnivores). Animals of all types grow and add organic matter to their body weight and their source of energy to complex organic compound takes as food. They are known as secondary reduces. All the living organisms whether plants or animals are all ecosystem have a definite life span after which they die. The dead organic remains of plants and animals provide food for saprophytic microbes such as bacteria, fungi and many other animals. The saprobes ultimately decompose the organic structure and break the complex molecules and liberate the inorganic components into their environment .these organisms are known as decomposers. During the process of decomposition of organism are known as decomposers.
During the process of decomposition of organic molecule the energy which kept the organic components bound together in the form of organic molecules gets lacerated and dissipated into the environment as neat energy. Thus in an ecosystem energy from the sun, input is fixed by plants and transferred to animals components. Nutrients are withdrawn from the substrate deposited in the tissues of the plants and animals cycled from one feeding group to another released by decomposition to the soil, water, air and then recycled. The ecosystem operating in different habitats such as deserts, forests grassland and seas are interring dependent of one another. The energy and nutrients of one may find their way into another so that ultimately all parts of the earth are interrelated, each comprising a part of the total system that keeps the biosphere functioning.
Thus the principal steps in the operation of ecosystem are as follows:
(i) Reception of radiant energy of sun.
(ii) Manufacture of organic materials from inorganic ones by products
(iii) Consumption of producers by consumers and further elaboration of consumed materials.
(iv) After the death of producers and consumers, complex organic compounds are degraded and finally converted by decomposers and converters into such form as are suitable for reutilization by producers.
The principal steps in the operation of ecosystem not only involve the production, growth death of living components but also they influence the Abiotic aspects of habitat.
So, there is transfer of both energy and nutrients from producers to consumers and finally decomposers and transformers levels.