Burning of Crop Residues: A Serious Challenge

                                                            
Apurba Koley*

Crop residues are mainly considered as trash or agricultural waste, but are also a precious natural resource. There are two types of agricultural crop residues: Field residues and Process residues. In this article we will discuss about the Burning of Field residues and its adverse effect on environment. Field residues are materials left in an agricultural field or orchard after the crop has been harvested. These residues include stalks and stubble (stems), leaves, and seed pods. The residue can be ploughed directly into the ground, or burned first. Burning is one way to dispose of the straw left after harvest so fields can be made ready for seeding. There are so many reasons behind the burning of crop residues. Some farmers find it difficult to deal with straw in normal ways. Burning straw is considered a low-cost solution alternative to tilling in the straw. Under such circumstances, farmers may feel they have no choice but to burn the straw.

There are so many Positive and negative impact of burning on environment. Now a day it becomes a major environmental issue in India.

            Fig:  Residue generated, residue surplus and burned in Major States of India in Million tons                                     ( Source: National Policy for Management of  Crop Residues)
Open field burning of crop stubble results in the emission of many harmful gases in the atmosphere, like carbon monoxide, N2O, NO2, SO2, CH4 along with particulate matter and hydrocarbons. These trace gases have adverse implications not only on the atmosphere but also on human and animal health (Gupta and Sahai 2005; Lal 2006; Agarwal et al. 2006; Canadian Lung Association 2007). These also result in the loss of plant nutrients and thus adversely affect soil properties.

Crop residues causes climate Change!!

Straw carbon, nitrogen and sulphur are completely burnt and lost in the atmosphere in the process of burning. This results in the emission of smoke which when added to the gases present in the air like methane, nitrogen oxide and ammonia can cause severe atmospheric pollution. Concentration of greenhouse gases (Carbon dioxide, methane and nitrous oxide) increases due to burning of crop residues. These gases tapped the heat which is responsible for global warming and rise in temperature and ultimately may cause the climate change. Considering the total impact of three greenhouse gases (Carbon dioxide, methane, nitrous oxide) in the next 20 year time horizon, it may be concluded that carbon dioxide would be dominant because carbon dioxide contribute is approx. 90% in warming due to crop residue burning. Similarly, methane, nitrous oxide contributes approx. 9% and 1% respectively. Burning of crop residue is not good because it will not only increase the global temperature but it may be responsible for Climate Change also. Emission of Greenhouse gases also causes various health risks, like Aggravating asthma, Chronic bronchitis and decreased lung function.

                       Fig :     Major Pollutants emitted during crop residue burning

 Burning leads to reduction of soil health

Crop residues are very important for Soils. It can furnish a protective layer to reduce soil erosion by wind and water. Crop residues help to increase the amount of Organic matter. In soil, as well as water holding capacity of the soil increased. It also provides ‘feed and forage’ for earth worms. When crop residue is burned all of those benefits are lost and other damage may be done. A significant reduction in total carbon and nitrogen pools occurs due to it. Burning decreases incorporated carbon sources for microbes, decreases soil ammonium levels and available soil phosphorous. 

                                            

                                          References

               

1. `https://en.wikipedia.org/wiki/Crop_residue
   
2. https://www.gov.mb.ca/agriculture/crops/crop-residue-burning-program/why-do-farmers-burn.html
3. Kumar,P.,Kumar,S.,Joshi,L.,(2015) Chapter 2: The Extent and Management of Crop Stubble,Socioeconomic and Environmental Implications Agricultural Residue Burning A Case Study of Punjab,India ,XIX,144p,5illus.
4. Tripathi,S.,(2015)Impact of Crop Residue Burning on Climate Change: A Scenario of Madhya Pradesh, India, Available online at: www.isca.in, www.isca.me
5. https://extension.usu.edu/cache/files/Short-and-Long-Term-Impacts-of-Burning-Crop-Residue-8-2015.pdf
    
6. Singh, R. P., Dhaliwal, H. S., Sidhu, H. S., Manpreet-Singh, Y. S., & Blackwell, J. (2008). Economic assessment of the Happy Seeder for rice-wheat systems in Punjab, India. Conference Paper, AARES 52nd Annual conference, Canberra. Australia: ACT. 
7. Canadian Lung Association. (2007). Pollution and air quality. http://www.lung.ca/protect-protegez/ pollution-pollution_e.php
8. Agarwal, S., Trivedi, R. C., & Sengupta, B. (2006). Air pollution due to burning of residues. In Proceeding of the Workshop on Air Pollution Problems Due to Burning of Agricultural Residues, held at PAU, Ludhiana Organized by the Indian Association for Air Pollution Control in collaboration with the Punjab State Pollution Control Board. New Delhi: Patiala and the Central Pollution Control.
9. Gupta, P. K., & Sahai, S. (2005). Residues open burning in rice-wheat cropping system in India: An agenda for conservation of environment and agricultural conservation. In I. P. Abrol, R. K. Gupta & R. K. Malik (Eds.), Conservation Agriculture—Status and Prospects (pp. 50–54). New Delhi: Centre for Advancement of Sustainable Agriculture, National Agriculture Science Centre.
10. Lal, M. M. (2006). An overview to agricultural burning. In Proceeding of the Workshop on Air Pollution Problems Due to Burning of Agricultural Residues, held at PAU, Ludhiana organized by the Indian Association for Air Pollution Control in collaboration with the Punjab State Pollution Control Board, Patiala and the Central Pollution Control Board, New Delhi.