Question

How do bacteria and cyanobacteria increase soil fertility? Explain.

Answer 1

Soil fertility requires constant supply of organic and inorganic nutrients. Bacteria are important sources for the enhancement of soil fertility. If the soil is not getting fertile, there will be depletion in the nutrients and potential yield of crops would not be reached. Cyanobacteria does the work of fixation of the soil.

Complete answer:
- Fertilizers can sometimes be harmful to the soil and they are also expensive sources. Therefore small-scale farmers cannot afford it. Therefore use of bio-fertilizers come into picture.
- Cyanobacteria which is also called blue green algae is a perfect example of a bio-fertilizer. They work as both nitrogen fixing bacteria and photosynthetic bacteria. Carbon and nitrogen sources are essential for the soil because they help to enhance the soil productivity. Therefore, these cyanobacteria increase the amount of nitrogen and carbon uptake.
- These cyanobacteria can tap the sun’s energy that is captured during the process of photosynthesis and fix the nitrogen from the atmosphere and turn it into a form that can be used by the plants.
- They also use the carbon dioxide, nutrients and water for conversion of solar energy into biomass.
- There is a bacteria called rhizobium which is symbiotic in nature. It gets attached to the roots of leguminous plants and enhances soil fertility by conversion of nitrogen into organic compounds.

Note: Bio fertilizers are simple to use and they do not pollute the environment or the soil. They can increase the yield up to 40 percent and hence the soil texture and quality is not compromised. However, these fertilizer require a good amount of care for long term storage purposes. Excessive acidic or basic soils also hinders the proper growth of the microorganisms.