Structure of the Ecosystem

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The community of living beings and the physical environment combine and work together to form a functional and structural unit of the biosphere. Both physical and living beings interact with each other and exchange materials. The ecosystem is a composite set of relations between the living and non-living aspects of nature. It includes plants, micro-organisms, water, birds, trees, air, and people. Each element in the ecosystem has the function of its own and are present in different sizes and shapes. All the living beings are dependent upon each other and components of ecosystems form an ecological community. If one side of the ecosystem is destructed or disappears, it will impact all other parts of the ecosystem. When an ecosystem is nourishing (or sustainable) it means that all the components are present in balance and are able to reproduce. An ecosystem can be as big as an entire ocean or as small as a drop of water.

Components of Ecosystem

The components of the ecosystem are divided into abiotic and biotic. Let’s discuss them in detail.

Abiotic Components

These are non-living and inorganic elements of the earth. It consists of water, soil, air, and light, etc. The gases present on the surface of the Earth like oxygen, nitrogen, carbon dioxide and various physical processes like earthquakes, floods, volcanoes, forest fires, etc. are all part of the abiotic components. These components decide the presence and absence of the living components in a specific area and also bring variety in different regions of the Earth.

The Sun is the main powerhouse of energy and is essential for the maintenance of life. The sun directly provides the energy to the plants while the animals use this energy through plants by eating them. The distribution of organisms depends on the energy available to them.

Water is important for the survival of living beings. The aqueous medium is largely responsible for the biochemical reactions in the environment. It also regulates body temperature. Water is also a habitat for many living forms.

It is one of the essential factors of the environment which in many ways influence the survival of the organisms. Different organisms are adapted to a different range of temperatures around them.

The existence of nourishing biosphere on this planet is the result of a suitable atmosphere that is present on the earth. It is made up of oxygen (21%), carbon dioxide, nitrogen (0.038%) and other inert gases (0.93%) like Neon and Argon.

The land is the habitat of different microbes, protozoa, fungi, small animals (invertebrates) and fungi. Plant roots break the soil particles into smaller pieces when it reaches down the soil to find water and nutrients. Organisms are also categorized as terrestrial and aquatic. Those who live on land are known as Terrestrial, and those who live in water are Aquatic.

a) Organic compounds like humic substances, lipids and proteins are formed as a result of inorganic decomposition.
b) Inorganic compounds like sulfur, water, nitrates, carbon dioxide, phosphates and ions of many metals are critical for the survival.

Latitude and altitude
The temperature of an area is greatly influenced by its latitudinal position which further leads to changing of climates like tropical, polar and temperate. The climate of a certain region determines the type of biome present there.
Wildlife is also affected by the distance in height from the sea level. The far it is from sea level on the upper side the more is the altitude. The variety of animals changes as we move from lower to upper altitudes. The air around the higher altitude is cool and dry, and thus animals adapt to the cold conditions here.

Biotic Components

These components consist of living organisms such as plants, animals, and microorganisms. These can be categorized according to their functional characteristics into consumers and producers.

Primary producers – Autotrophs (self-nourishing)
Green plants are basically primary producers. Some algae and green bacterias also make it in this category. Primary producers make carbohydrate from simple inorganic raw substances like water and carbon dioxide. The presence of sunlight is another important ingredient for this formation to occur. This is known as Photosynthesis. These carbohydrates are further supplied indirectly to other living beings.
In a terrestrial ecosystem, producers are generally in the form of herbs and woody plants and trees while in aquatic ecosystem producers are generally small, and some might be too small to be only seen with a microscope.

Consumers – Heterotrophs or phagotrophs
Consumers cannot obtain their own food and are dependent on others for nourishment. The derive nourishment from animals, plants, or both. These can further be classified into macro and micro consumers.

a) Macro Consumer
They feed on plants, animals and sometimes both. These are listed on the basis of their sources of food.

Herbivores are the consumers that depend on plants to get nourishment. For example- cow, rabbit, etc. These are also known as Primary consumers.
Secondary consumers are dependent on primary consumers for their nourishment. For example – Wolves.

Carnivores are the consumers that depend on secondary consumers are known as Tertiary consumers. Lion is an example of a tertiary consumer.

There is another category of consumers which eat both plants and animals. These are called Omnivores. Man and monkey are examples of Omnivores.

b) Micro Consumers – Saprotrophs (decomposers or osmotrophs)
Microorganisms like bacteria and fungi extract energy and nutrients from the dead and decaying organic matter (detritus) of animals and plants. The producers reuse the products that are released in the atmosphere during the decomposition of dead and decay. Hence these organisms are also called detritivores.

Cite/Link to This Article

  • "Structure of the Ecosystem". Geography Revision. Accessed on January 26, 2021.

  • "Structure of the Ecosystem". Geography Revision, Accessed 26 January, 2021.

  • Structure of the Ecosystem. Geography Revision. Retrieved from