UPSC Prelims 2020 Question:

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?

Explanation:

• Biochar is a type of charcoal produced through pyrolysis, which occurs when organic matter is heated in the absence of oxygen.
  
  
• Biochar may increase the soil fertility of acidic soils and increase agricultural productivity. It can also be used in hydroponics and vertical farming. So, statement 1 is correct.
  
  
• Biochar has the potential to improve legumes' natural ability to fix nitrogen to the soil. Adding biochar to soil not only helps to sequester carbon, but it also has numerous soil health benefits that will aid farmers in adapting to climate change and increasing productivity. In addition to promoting the growth of nitrogen-fixing microorganisms, biochar can reduce soil Nitrogen dioxide emissions, increase nitrogen use efficiency, and increase nitrogen retention in the soil. So, statement 2 is correct.
  
  
• It can improve the water holding capacity of the soil due to its porous nature. So, statement 3 is correct.
  

Therefore, option (4) is the correct answer.

Subject: Environment | Waste Management