Biotic Factors- Definition, Types, Examples and Factors Affecting

Biology Educational Videos

Last Updated on February 10, 2021 by Sagar Aryal

The ecosystem is made up of biotic and abiotic factors. Abiotic factor comprises non-living components like sunlight, temperature, water, soil, wind, humidity and radiations. These are the physical and chemical agents that ultimately affects the biotic factors. Biotic factor or components means the living things of an eco-system. It is also responsible for the different outbreaks of diseases. Both abiotic and biotic factors work together. It determines what the ecosystem will look like and the availability of the ecological niches.

Biotic Factors
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What are Biotic Factors?

Biotic factors include living things like plants, animals, bacteria, etc. It is divided into three main groups;

  • Producers
  • Consumers
  • Decomposers

1. Producers

  • Producers are known as autotrophs.
  • By the use of inorganic materials and energy, they prepare their own food. 
  • It is considered the first life form. It is because, in the early days of origin, there were no consumers to feed on.  

There are two major classes of producers. They are

  • Photoautotrophs
  • Chemoautotrophs

a. Photoautotrophs

  • They use sunlight as the source of energy and carbondioxide as the source of carbon.
  • They mostly use the pigment, chlorophyll for capturing the photon from the sun.
  • Similarly, there are also pigments like rhodopsin and carotenoids which are found in some bacteria, algae, and phytoplankton. They are used for photosynthesis.
  • Later they produce essential things like sugar, protein, lipids, etc.

Examples: Green plants,  green algae, and some bacteria.

b. Chemoautotrophs

  • They use chemical agents like hydrogen, iron, and sulfur as the source of energy. 
  • They are usually found in places where the plants cannot grow. 
  • They are found at bottom of the ocean or in acidic hot springs.
  • They are also involved in nitrogen fixation.

Example of Chemoautotrophs: Methanogens. They are the microorganism which are capable of making the methane gas. 

2. Consumers

  • They are also known as heterotrophs.
  • They don’t prepare their own food by themselves as the producers. It includes all the heterotrophs.
    • Herbivores: Animals like a cow, buffalo, the goat which depend directly on plants for food. They are primary consumers.
    • Carnivores: Animals like lions, tigers, which are flesh-eating animals. They depend on the herbivores for food. They are secondary consumers.
    • Omnivores: Animals like dog, cat which eat depend on both the plants and animals

3. Decomposers

  • They are also known as detritivores.
  • They use organic compounds as the source of energy from the producers and consumers.
  • In an ecosystem, decomposers play a vital role, as the complex substances are broken down into simpler forms.
  • Such a simpler form can be further utilized again by the other organisms. It includes different soil bacteria, fungi, worms, and flies.
  • When the animals die they get decomposed because of decomposers. Even plants, fruits start rotting, it’s because of decomposers.
  • Decomposers play the important role in metabolizing waste products.
  • Example of decomposer: Mushroom

For example, Composting

  • In our daily life, different wastes are obtained from the kitchen.
  •  The leftover foods, fruits, vegetables, etc.
  • They are collected separately and put in a pile.
  • After some time, it yields the fertilizer which is organic and of high quality which can be used in the field.

Example of biotic factors

1. Human

Human plays the vital role either in conservation or the destruction of nature. Human has got both the positive and negative side. The positive side is humans can utilize natural resources and conserve the existence of other animals too. Drastic changes can be made regarding the conservation. But due to rapid urbanization and industrialization, the emission of excessive carbon dioxide and carbon monoxide gas, there is depletion in the quality of air.

2. Cyanobacteria

They are the single-celled autotrophic organism which was considered to be the first living organisms on earth. Using solar energy they convert the organic compounds into inorganic compounds. They are capable of making oxygen by using the carbondioxide.

Factors Affecting

There are different factors of the ecosystem. Directly or indirectly they depend on each other for their existence.

Availability of Food

It is considered to be the limiting factor. When there is a shortage of food, animals will die due to starvation. For eg: when the herbivores die, carnivores will also die due to starvation. The whole ecosystem will be disturbed.

Presence of Predator

In an ecosystem, to maintain balance, there must be a balance between prey and predator. When there is an increased number of predators but prey is few, in such condition, the prey will disappear. Suppose in a grassland, if the number of the cattle are more but grassland is few or supposes if deer is few but tigers are more in number, then in such condition, grassland and deer will get disappear.

Presence of Parasites

Parasites are those organisms that harbor or live in other living organisms like plants and animals for their existence. We can take an example of the ectoparasites like lice which are normally present in the untidy hair of children. Endoparasites like roundworms, hookworms live in the intestine. Parasites obtain nutrition from the host.  For eg, hookworm results in anemia as it causes the loss of blood. When parasites lodges inside the host, use the nutrition of the host, it will result in illness.

Competition between the species

It’s the law of nature, for their survival and existence, animals need to compete with each other. Only those species which has the capacity to obtain food will survive, they will adapt in nature whereas others will eventually die. Back to the theories of evolution, it suggested short neck giraffes got disappeared whereas only the long-necked giraffes existed, it’s because of access to food.

Similarly, in our human body too, there is the presence of normal flora. Not all bacteria are harmful. Some good bacteria are also present in our body whose presence prevent the colonization of the pathogens. Such harmful organisms won’t get access to our bodies.

There is always competition between the organism either it’s about the microorganisms or the other animals.

All the biotic factor they can’t function solely. Directly or indirectly they are dependent upon one another. All the biotic factors are influenced or affected by the abiotic factor. As a result, their coordination, shape the ecosystem.

References and Sources

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