Burning Topic - Smog Rules the North India
The start of the winter season has come to be associated with the smog choking and toxic atmosphere in north-west India. Air pollution caused by stubble burning after harvesting of paddy seems to be worsening with every passing year. The smog is not only causing health hazards but also affecting germination and growth of crops.
The burning of paddy stubble has received a strong criticism over the past few years and has also given rise to an urgent need to find solutions. So now it has become a need of time to find the best suitable alternatives by the use of technological advancements. The various technical solutions to solve this problem have been discussed in this article.
What is Stubble Burning?
Stubble burning is the deliberate burning down the remains of paddy and other grains. This is a financially cheap practice to get rid of residues left after the harvesting, while also cleaning the weeds from the fields.
Nowadays farmers are using combine harvesting methods for harvesting paddy. Combines are the machines that harvest, thresh; separate the grain and also removes the grain from the husk, all in one go. But the problem with combine machines is that they do not cut close to the ground, therefore, they leave residues behind. After harvesting, paddy farmers are always in a hurry to sow wheat crop to maintain the rice-wheat cycle. The delay in sowing can cause the loss in production and productivity of crops in the green belt.
Why are Farmers Opting This?
As per agriculture experts, the burning of paddy straw deteriorates soil fertility. However, farmers in their haste to clear fields for sowing wheat, often try to dispose of paddy stubble in eco-unfriendly ways. Wheat is 140-150 day crop which is harvested in mid-April when the temperature is about 35 degrees C. If the sowing of wheat is delayed then it will adversely affect the product quality. Further talking about the problem, after paddy harvest farmers are left with very little time to prepare the fields for wheat sowing. So the burning of leftover residues (stubble) becomes an easy rescue option.
The quick and cheapest solution for farmers is burning down the stubble. Farmers choose this method because it is cheap and it clears the field quickly, kills weeds, including those resistant to herbicide, kills slugs and other pests and also can reduce nitrogen tie-up, etc.
Alternatives to Stubble Burning
While there are many options that have been offered to handle the stubble in an efficient fashion, none seem to be tied with an appropriate financial or institutional mechanism. The most appropriate solution presented involves ploughing back the stubble in the ground. But this is also economically unfeasible for the farmers because of the high cost of both manual labour and mechanized options. The severity of this problem needs innovative thinking to find out alternatives to stubble burning. This problem can be technically resolved in many ways:
• Turbo happy seeder is a new invention in the field of agriculture machinery. This machine is mounted on the tractor that not only cuts and lifts the stubble but also sows wheat into the bare soil and deposits the straw over the sown area. This can also be fitted with the Super-Straw Management System (SMS) which further allows spreading the straw evenly on fields.
• Happy Seeders and SMS allow the stubble rest in the fields, where they are naturally converted to manure for the crops. This helps in reducing waste and optimizing the growth of crops in the field.
• Another solution involves providing stubble collecting machines for the collection of paddy straw in the form of bundles to be used for various other purposes. These bundles could be used in the packaging industries to make environment-friendly packaging boxes than other non-disposable materials like thermocole and plastic, etc. Also, this will include the use of paddy straw for packaging fragile items like crockery and glass, etc.
• The stubble can be used for the production of manure after collecting it in one place. At village levels, workers can be hired by the panchayats to collect farm residues and paid under the government schemes like MNREGA. Providing labour would give temporary employment to people in need.
• Reducing the paddy production will also reduce the stubble. In the long run, an area under rice production should be reduced by encouraging the cultivation of high-value crops like vegetables, fruits, oilseeds, pulses, maize, bajra, etc. The state and centre governments could incentivise the farmers to grow these crops. If the production of other crops would be made more lucrative, more farmers will grow this. This will save water, energy, and also keep our air clean.
• Use of paddy residue as a fodder for animals is not very popular in Punjab because of high silica content in rice residue. Instead, 40% of wheat straw is used as a fodder to feed animals. A study shows that cattle fed with this rice residue feed showed an improvement in health and milk production.
• Use of rice residues in bio thermal plants are being encouraged by many institutions and departments for the generation of electricity. The thermal plant at Jalkheri, District Fatehgarh Sahib set up in 1992 which is based on the use of Biomass was the ﬁrst plant in India. Another example of the plant is Malwa Power Pvt. Ltd. at village Gulabewalla using crop residues.
• Use of rice residue as bedding material for cattle is found to be very comfortable during the winter season. The study shows that paddy straw bedding during winter helped in improving the quality and quantity of milk as it contributed to the animal’s comfort, udder health and leg health.
• Use of paddy straw for mushroom cultivation. Paddy straw is used for cultivating mushrooms in tropical and subtropical areas and they are also named as grass mushrooms.
• Uses of paddy straw in the paper industry are considered to be the ideal raw material. Paddy straw is used in combination with wheat straw in 40:60 ratios for paper production.
• The new technology is developed by Sardar Patel Renewable Energy Research Institute for making biogas from paddy straw. As per this technology 300m3 of biogas will be produced from 1t of paddy straw.
• Incorporation of paddy straw in the soil will improve physical, chemical and biological properties of the soil
Effects of Stubble Burning
Burning down the stubble not only pollutes the air but also causes damages to the farmer in many ways. The heat produced after burning down the stubble results in the loss of very important nutrients for the soil e.g., organic carbon, nitrogen, phosphorous, and potassium, etc. The heat produced by burning the stubble interferes the physical and chemical properties of the soil, affects the acidity of the soil and also affects the soil microorganisms by killing them or by making them inefficient.
A study conducted by the National Aeronautics and Space Administration (NASA) concluded that there is a strong link between stubble burning and the pollution of PM2.5 levels in Delhi during the months of October and November.
Studies show that stubble burning causes massive air pollution by releasing smog-laden with harmful gases such as sulphur dioxide, nitric oxide and carbon dioxide.
From the above, it is clear that farmers have very little choice to burn the stubble. They have the pressure to sow the next crop. State governments are trying to stop stubble burning by penalizing the farmers, but as of now, to no avail. Burning is continued. The government should offer farmers other alternatives like in the case of Almond Board of California. Almond dust is the major issue during the time of almond harvest in California. Almond Board of California has issued a practical guide to literate almond growers about the effective harvesting techniques to reduce the almond dust. After thoroughly studying how the dust is generated at almond harvest research has developed numerous methods that growers can use to reduce dust at harvest, e.g. changing sweeper head height, reducing the number of blowers passes, using metal tines, and reducing pickup machine speed. Based on that research many equipment manufacturers have made changes to sweepers and pickup machines to reduce dust emissions. On the grower’s part, they were given incentives from the USDA Natural Resources Conservation Service (NRCS) for use of this low-dust technology.
* Associate Editor Food Marketing & Technology Magaizne, India