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 a 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

10. Ans: d

Explanation:

Biochar is a charcoal-like product that contains no petroleum. It is made by heating biomass such as herbaceous or woody crop residues, non-salvageable timber and slash, or animal manure, in a contained system.

There are many potential uses for biochar including water treatment, land reclamation, and carbon sequestration. 

Biochar may also be used as a soil amendment for two purposes – to improve plant health and to store carbon. It is predicted that at least 50% of the carbon in any piece of waste turned into biochar becomes stable, locking away that carbon for a period of several to hundreds of years, offsetting its contribution as a greenhouse gas in the form of carbon dioxide.

Biochar provides several benefits to the soil by increasing its nutrient contents and water retention capacity. This is due to the cation exchange capacity and porous nature of the biochar, which is essential in promoting plant growth and development

Incorporation of biochar into growing medium has been found to enhance crop yield, increase populations of plant growth-promoting microbes and promote disease suppression.

Inoculating a peat medium with biochar with Rhizobia and mycorrhizal fungi may serve as a potential microbe activator. 

Vertical farming generally refers to the growing of crops mostly vegetables, ornamentals, and herbs on stacks of indoor shelves using artificial light and nutrient solutions, without much sunshine and soil. Such farms are not dependent on seasons/controlled environment and have ability to enhance production round the year with little risk of crop failure.

The usage of biochar can be also interesting for the urban farming industry. In fact, green roofs are seen as “privileged areas” for retaining rainwater and reducing the effects of urban heat islands and it is  also a part of vertical farming. 

The reported benefits of biochar include: 

• Greater uptake of nitrogen (N) stimulating plant growth 
• Stimulation of beneficial soil life, including mycorrhizal fungi
• Increased cation exchange capacity (ability the soil’s ability to retain nutrients) 
• Increased nutrient availability 
• Reduced nutrient leaching 
• Improved soil porosity
• Greater water retention in soil

Hence, option d is correct.

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