Q. What is the use of biochar in farming?
1.Biochar can be used as a part of the growing medium in vertical farming.
2.When biochar is a part of the growing medium, it promotes the growth of nitrogen-fixing microorganisms.
3.When biochar is a part of the growing medium, it enables the growing medium to retain water for longer time.
Which of the statements given above is/are correct?
a) 1 and 2 only
b) 2 only
c) 1 and 3 only
d) 1, 2 and 3
Correct Answer : d) 1, 2 and 3
Question from UPSC Prelims 2020 GS Paper
Explanation:
Biochar in Vertical Farming
Biochar can be used as a part of the growing medium in vertical farming. This is true. Biochar is a highly porous carbon-rich material obtained from the pyrolysis of organic biomass under limited oxygen conditions. Its structure is beneficial for use in growing mediums because it can help improve soil structure, aeration, and water holding capacity, which are crucial factors in the confined spaces of vertical farming systems.
Promoting Nitrogen-Fixing Microorganisms
When biochar is a part of the growing medium, it promotes the growth of nitrogen-fixing microorganisms. This statement is also correct. Biochar has been found to provide a conducive habitat for various microorganisms, including those that fix nitrogen. Its porous structure not only offers shelter but also can help in retaining nutrients that are beneficial for these microorganisms. Nitrogen-fixing microorganisms are essential for converting atmospheric nitrogen into forms that plants can absorb and use, thus enhancing soil fertility and plant growth.
Enhancing Water Retention
When biochar is a part of the growing medium, it enables the growing medium to retain water for a longer time. This is accurate as well. One of the key properties of biochar is its ability to retain water. This is due to its high porosity and large surface area, which can hold water molecules effectively. In farming, especially in conditions where water might be scarce or in systems like vertical farming where efficient water use is crucial, biochar can help in maintaining moisture levels within the growing medium, reducing the need for frequent watering and enhancing drought resistance of the plants.
Therefore, all three statements given about the use of biochar in farming are correct, making option d) 1, 2, and 3 the right answer.