Less pollution, more soil fertility

Context:

Stubble burning:

Stubble burning refers to the practice of farmers setting fire to plant debris that remains on farms after harvest.
The origin of stubble burning can be traced to the advent of the Green Revolution.
Mechanised harvesting, a feature of the Green Revolution, utilised the combined harvesting technique which left behind substantial plant debris after harvest.
The combined harvesting technique left behind one-foot-tall stalks.
This prompted stubble burning as a low-cost and speedy solution to get rid of the plant debris just in time for the next crop sowing.
The Green Revolution increased greatly rice and wheat production, which simultaneously increased stubble post-harvest.

Impacts of stubble burning:

1. Health impact:

Stubble burning releases harmful gases including nitrogen oxide and carbon monoxide into the atmosphere.
In recent years, this practice has created vast smoke blankets across the Indo-Gangetic Plain, including Delhi.
This has exposed millions of people to air pollution.
As per a TERI (The Energy and Resources Institute) report, in 2019 the air pollution in New Delhi and other parts of north India was 20 times higher than the safe threshold level as prescribed by the World Health Organization.

2. Effect on soil fertility:

Stubble burning has a negative impact on soil fertility by destroying organic fertilizers, killing critical soil microbes and reducing groundwater levels.

Steps taken to tackle stubble burning:

In 2013, stubble burning was banned by the Punjab state government.
In 2015, the National Green Tribunal imposed a ban on stubble burning in Rajasthan, Uttar Pradesh, Haryana and Punjab.
The governments were directed to assist farmers by ensuring the availability of equipment like happy seeders and rotavator to the farmers.
Stubble burning has been made an offence under Section 188 of the Indian Penal Code and the Air (Prevention and Control of Pollution) Act of 1981.
Recently, in Aditya Dubey v. Union of India case, the Supreme Court appointed a one-man committee to monitor and provide steps to prevent stubble burning activities in Punjab, Haryana and U.P.
The Union government has brought out an ordinance to set up a permanent commission for air quality management.

Way forward:

There needs to be a robust system in place to detect and notify authorities about stubble burning. Suitable action against violators could deter other farmers.
The administration should support the farmers through setting up of Custom Hiring Centres which will facilitate farmers to remove stubble by providing them with machinery such as the happy seeder, rotavator, paddy straw chopper, etc. on rent.
PUSA decomposer: An innovative method called the PUSA Decomposer, developed at the Indian Agricultural Research Institute, Pusa, is being tested by the Union government.
The PUSA Decomposer is a set of four tablets made by extracting fungi strains that help the paddy straw to decompose at a much faster rate than usual, giving farmers the option to shred the straw, spray a solution containing the fungal strains, and mix it with the soil for decomposition.
This method has the potential to both reduce air pollution and increase soil fertility and consequently help improve agricultural productivity.
Biofuels: Developing stubble based biofuel generating methods could incentivize the farmers to avoid stubble burning by attaching economic value to the stubble.
Apart from helping avoid stubble burning, this could also provide an avenue to increase the incomes of farmers, incentivize biofuel-based units in rural areas and also help reduce India’s import dependency of crude oil.