Delhi’s tryst with decreased air quality during winters is not new, it’s an annual occurrence. The severity of air pollution last year crossed all safety indices forcing the government to declare a public health emergency. The air quality index monitors across the city recorded ratings of 999, the reading was 50 times more than the safety level prescribed by the World Health Organization. 

This year, the story is no different. The air quality index calculated using the data calculated by the Central Pollution Control Board’s 37 monitoring stations in Delhi,  Delhi’s air quality post diwali is at a constant 389 which is in the ‘very poor’ category. Stubble burning, meanwhile, appears to have begun over parts of Punjab and Haryana, going by fire spots mapped by NASA. However, data from Visible Infrared Imaging Radiometer Suite (VIIRS) show less number of fires this year in Punjab and Haryana compared to the same period over the last five years, indicating a delayed stubble burning season. As per VIIRS data, the cumulative fire count in Haryana this year during mid-October stood at 442. The corresponding figure was 750 in 2020, 723 in 2019, 619 in 2018, 988 in 2017 and 1,095 in 2016, going by VIIRS data. In Punjab, the cumulative fire count on October 11 this year was 918, compared to 2,996 in 2020, 869 in 2019, 529 in 2018 and 1,392 in 2017.

The question is what is the need to burn the stubble, why do farmers in Punjab and Haryana practise it? 

Punjab produces the majority of the country’s food surplus and in order to do so the state in the past indulged in rigorous and intensive farming techniques. One of such techniques was to use inexpensive and subsidized electricity to pump out groundwater for irrigation. This fuelled water shortage as the groundwater reserves began to deplete due to exploitation. The Punjab government as a measure to combat it, in the year 2009, enacted the Punjab Preservation of Subsoil Water Act. The Act changed the way farmers planted rice. The crop is traditionally cultivated in two stages, it is first cultivated in a nursery and then transplanted to a field. The Act prohibited sowing the crop in nurseries before May 10 and transplanting before June 10 every year. This calculated delay gave enough time for the seasonal monsoon to recharge the aquifers, but it bereaved the farmers of enough time for the next harvest. A delayed rice harvest in October leaves farmers with less than a month to prepare the field for the winter wheat crop which is ideally sown in November. With barely any time left to prepare the fields for the next crop, the small scale farmers resort to the cheapest and quickest method available — burning the crop residue.

The crop residue or more specifically the residual rice straw – is a product of mechanised agriculture. When paddy is harvested by a combined harvester and thresher, the machine leaves behind a significant length of straw and stubble on the field. This prevents other machines from sowing wheat seeds. With only 10-15 days between the rice-harvesting season and the wheat-sowing time, farmers often burn the stubble to quickly eliminate the paddy stubble. According to some estimates, farmers burned about 11 million tonnes of stubble in Punjab and Haryana, out of the 27 million tonnes of paddy stubble produced last year. 

Apart from contributing to air pollution, stubble-burning deteriorates the soil’s organic content, essential nutrients and microbial activity – which together will reduce the soil’s long-term productivity. It strips soil of essential nutrients such as nitrogen, phosphorus, and potassium (NPK). It raises soil temperature to about 42°C, thus displacing or killing important microorganisms up to a depth of about 2.5 cm. 

There are many alternatives to stubble burning, and despite being aware of the ill effects of stubble burning, it continues to be the modus-operandi for farmers regarding post-harvest waste management. 

Farmers have a tough time unlearning the age-old practice of stubble-burning. Alternatives to stubble burning are not popular because they impose additional operational expenses, often from the farmer’s pocket.There are multiple alternatives to stubble burning, and farmers can choose between the technologies and machines most suited to their particular local conditions, with the objective of ‘no burning’. The government should play the part of an enabler by spreading awareness about the pros and cons of each option, so as to eliminate confusion and ease the adoption of new technologies by removing socio-economic barriers. For this, the state governments can rope in block-level agricultural officers and officials of agricultural produce market committees to develop and implement comprehensive ‘no burning’ strategies at the local level.