Microorganisms are present everywhere and form an integral part of the planet earth. As their metabolic activity is quite strong, they can thrive in extreme environmental conditions. We can find them in extreme conditions like acidic waters, deep ocean trenches, frozen mountains, and hydrothermal vents. Microbial ecology is the study of the relationship of microorganisms with one another and with their environment.
When we talk about the environment, microbial ecology includes the study of their role in the bio-degradation of wastes including the industrial, agricultural, domestic, etc. It also includes the study of the role of microbes in the treatment of soil pollution, marine pollution, water pollution, etc.
Role of microorganisms in the Ecosystem
For an ecosystem to work properly, all the organisms that are part of it have to work together. Microorganisms also form a very important part of the ecosystem and the role they play is very significant. They are involved in various important processes like the generation of oxygen, decomposition, evolution and symbiotic relationships. Let us look at some of the important roles that they play.
- Decomposition: The process of breaking down the complex matter of dead animal and plant into a simple or the basic molecules is called decomposition. This process provides the nutrients which could be used by the plants and animals. Also if the decomposition process does not take place, we can imagine what would be condition of the environment with all the cluttered remains of dead plants and animals everywhere.
- Generation of oxygen: The cyanobacteria or the blue green algae found in the oceans are responsible for the production of almost all the oxygen that is present in the atmosphere.
- Recover the nutrition from the organic matter: The decomposition process releases the essential nutrients like N, P, K etc. bound in the dead organic matter and these minerals are then made available to the primary producers like the green plants. This recycling process keeps the balance in the ecosystem and the productivity cycle is continued.
- Fixation of Nitrogen from atmosphere into usable form: Bacteria are the only organisms that are capable of removing the atmospheric nitrogen gas N2 and fixing it into a usable nitrogen form like the NH4 or NH3. Some of the examples of the nitrogen fixing bacteria are cyanobacteria, rhizobium etc.
- Give plant roots access to nutrients in the Soil: As roots use all the available nutrition present in the soil near them, a zone of nutrient depletion is formed near the roots. To gain more nutrition, the roots have to either go deep into the soil, or grow small root hair that can help absorb the nutrition from the soil. The roots can also form an association with a group of fungi called mycorrhiza whose hyphae helps them absorb the nutrients from the soil. Another advantage of this association is that the hyphae can secrete enzymes that can break down the organic molecule and make the inorganic nutrients available to the plants.