What is stubble burning?

• Stubble burning is the process of intentionally setting fire to the straw stubble that remains after grains, like paddy, wheat, etc., have been harvested, to remove them from the field to sow the next crop.
• This is commonly practiced by farmers of Punjab and Haryana.
• During the late 1970s and early 1980s, which was the Green Revolution era, Punjab and Haryana shifted from their traditional crops (maize, pearl millet, pulses and oilseeds) to the wheat-paddy cultivation cycle. In Punjab and Haryana, while the paddy crop is usually harvested between the first and last weeks of October, the wheat crop is sown from the first week of November. Due to shortage of labour and 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.

Who does farmers resort to stubble burning?

• Lack of knowledge about effective alternatives to stubble burning.
• Lack of affordable mechanisation to cater the needs of millions of farmers.
• Unlike wheat straw, which is commonly used as animal feed and sells at good prices, rice is unfit to be fed to cattle because of its high content of unpalatable silica, and, therefore, has little market value.

Why is stubble burning a concern?

Impact on agriculture

Harms microorganisms

• The heat from burning paddy straw which when penetrated into the soil, elevates the temperature and thereby kills the bacterial and fungal populations critical for a fertile soil.

Vulnerability to diseases

• It causes damage to friendly microorganisms and facilitates growth of ‘enemy’ pests and as a result, crops are more prone to disease.

Loss of essential nutrients

• Stubble burning leads to a loss of significant amounts of nitrogen, phosphorus, potassium and sulfur  besides organic carbon resulting in additional fertilizers being used by farmers to replenish the same.

Growth of weeds

• Weeds are more prone to grow in the field cleared by burning the stubble and since growth of weeds affects the health of the principal crop, farmers respond by using chemical weedicides that increase the cost of production and aggravates biomagnification.

Impact on environment

Air Pollution

• Crop residue burning releases large amounts of harmful pollutants like carbon dioxide (CO2), carbon monoxide (CO), oxides of sulphur (SOX), particulate matter and black carbon which directly contribute to environmental pollution.

Impact on health

• The massive amount of smoke and toxic gases that the crop fires exude causes health problems, ranging from eye and breathing troubles to more serious illnesses.

Why in the news?

• With the paddy-harvesting season almost nearing, none of the northern rice-growing states seems to have a workable strategy in place to prevent farmers from burning crop residues.

Issues with current strategies to prevent stubble burning

Microbial stubble decomposer

• Takes longer time (20-25 days) to decompose the leftover biomass, which is too long for farmers to wait for sowing the next crop.

Crop residue management machinery

• Involves additional expenses, which the farmers find unaffordable without financial assistance.

Other machineries 

• Although machines like Happy Seeders and Super Seeders can sow the new crop without removing the paddy remnants from the fields, these are costly machines, which individual farmers cannot buy.

No financial aid

• Though state governments subsidise the cost of these machines for cooperative societies and other custom-hiring service providers, they do not offer financial aid to farmers to meet the charges for their use.
  • Haryana is the only state that offers Rs 2,500 per acre for this purpose which is still low to cover the cost.

How can we fix these issues?

• Unless rice straw is also converted into an economic good, farmers would have no incentive to spend money on disposing it of in an environmentally safe manner.
• Thus stubble burning is essentially an economic issue that requires an economic solution.

Economic solution

Making gainful uses of crop residues. 

• Making various kinds of paper and hard boards, fuel briquettes out of crop residues for replacing coal in thermal plants.
• Convert crop residues into biofuel for blending with petrol. 
  • Haryana has already set up a 2G ethanol plant in Panipat, near the Indian Oil Corporation’s refinery, to produce alcohol from paddy and other agricultural wastes.

Conclusion

• A lasting solution to the menace of stubble burning lies in making it a source of income for the farmers by promoting such economic uses of this biomass.