Plumes of smoke arising from the fields is a common sight in Punjab and northern Haryana (India) during rice harvesting season. In the months of October-November it almost asphyxiates anyone who ventures out of house, be it a village or city. The reason is burning of paddy stubble.
Burning of rice straw remains emits trace gases like carbon dioxide, methane, carbon monoxide, nitrogen oxide, sulphur oxide and large amount of particulate matters, which adversely affect human health as well as the environment. In 2013, the magnitude of stubble burning was so high that it received international attention. The National Aeronautics and Space Administration (NASA) released a satellite image showing large numbers of fires across millions of hectares of agriculture fields in Punjab and Haryana.
Farmers in the state complain that rice straw is a huge problem for them because they follow mechanised agriculture. When rice is harvested by a combine harvester, it leaves a significant length of straw on the field. So crop residues in combine-harvested fields are burnt. Besides, both wheat and rice are long-duration crops. With a short period available between rice harvesting and wheat plantation, burning is the easiest and quickest way to get rid of rice straw. A Jat farmer adds that increasing labour cost is another reason farmers prefer setting fire to their vast swathes of paddy fields after they have harvested the crop.
After China, India is the world’s largest producer of paddy. India produces 98 million tonnes of paddy with roughly 130 million tonnes of straw. Of this, about half is used as animal fodder. The rest is mostly burned in the fields, though a small amount is also consumed by brick kilns and the paper and packaging industry. Despite such huge amounts of rice straw generated, farmers in the country are yet to realise the potential of this agricultural waste as a form of manure and as a profitable raw material for various industries.
Where’s the profit?
According to the local farmers, on average one gets about two tonnes of rice straw per acre (0.4 hectare). ‘The combine owner or operator charges an additional Rs. 850 per acre for harvesting that leftover portion which is of no use to us’, says a farmer. It cannot even be fed to the cattle. Blades of fodder cutter easily get blunt by the thick and sharp straw.
Moreover, in the area only brick kilns buy rice straw, but they are limited. Besides, selling rice straw to kilns is not profitable. ‘They pay the farmers Rs. 600-700 a tonne, which means farmers get Rs. 1,200-1,400 per acre. Now, subtract Rs 850 [forming] the rental cost of the combine harvester and the transportation cost [coming to] Rs. 300, which is borne by the farmer, from the amount. All the farmers get is between Rs. 50 and Rs. 250. Where is the profit?’
Another farmer says: ‘Of late, power companies are approaching us to buy rice straw. They are offering between Rs. 500 and Rs. 700 a tonne. Last year, the paper and packaging industry had bought straw for Rs. 1,400-1,700 a tonne’. That was a one-off deal though. In the absence of assured returns, farmers find stubble burning an economic way of managing the agro-waste.
Back in the soil …
Every year about 12 million tonnes of rice straw is burned in the state of Punjab only. According to agricultural specialists, this leads to nutrient loss from the soil which is equivalent to $18 million worth of urea. Scientists from Haryana Agricultural University (HAU) and Punjab Agricultural University (PAU), India, have developed a simple and rapid composting technique to convert huge piles of rice straw into organically rich soil.
It takes about 45 days to prepare this rice straw compost which helps conserve nitrogen and other nutrients contained in the straw, they say. The compost contains 1.7 to 2.1 per cent of nitrogen, 1.5 per cent of phosphorous and 1.4 to 1.6 per cent of potassium. It helps improve crop yield by 4 to 9 per cent.
However, the problem is that farmers find it labour-intensive. The problem with the farmers is that they want quick solutions. That is why the rice straw compost technique is unsuccessful in India.
Another scientist offers another use of rice straw – mulching. In this method, straw is spread across the soil surface and allowed to decompose naturally into the soil by the activity of worms and other organisms. A few farmers in Haryana have adopted it. Farmers in Andhra Pradesh, another rice-growing state of India, have also resorted to this method as it helps maintain soil fertility. Moreover, crops like pigeon pea, soybean and maize can also be easily grown with mulch on the surface.
But environment-friendly agriculture asks for extra effort and time. With farming becoming less remunerative, farmers are looking for easy and quick solutions. This is perhaps the reason why burning of rice straw continues unabated across Punjab and Haryana despite advisories by agricultural universities and the district administration as well as FIRs by agriculture officers against erring farmers.
Power industry offers a way out …
For the past two years, the people of Haryana and Punjab are witnessing relief from choking air during harvesting seasons. Complaints of respiratory problems have also reduced. This is attributed to hundreds of farmers who decided to sell their rice straw to a power company, Punjab Biomass Power Ltd (PBPL), in Ghanaour village.
The company’s agents approached the farmers to harvest the straw for a dividend in cash. The proposal was luring enough, but the farmers had strict time constraints. The company offered its own machinery to harvest and collect straw on time so that farmers would not experience delays for the next crop. The farmers agreed.
Last year PBPL generated 12 MW while helping farmers reduce the pollution levels considerably. According to statistics, ‘A 12 MW rice-straw power plant typically needs 120,000 tonnes of stubble, which can be collected from about 15,000 farmers’.
Power sector pundits say that energy demand may increase by 50 per cent by 2030 and, as sources say, power production from rice straw is a promising way to meet the demand. If enough biomass power plants are set up, it will provide a new source of income to farmers.
But the power industry pays less to farmers than the packaging industry. The paper and packaging industries need straw in small amounts and hence are spoiling the market. The requirement of power units is 350 to 400 tonnes a day and they pay about Rs. 800 a tonne for non-basmati rice straw and Rs. 1,500 for basmati straw as it has high calorific value. These prices may increase in the future as the market becomes competitive. Though PBPL is currently incurring losses it is hoped that it will be able to make profits in the coming two to three years.
With several applications, increasing demand and competitive prices, it seems farmers have no dearth of options for managing the agro-waste in a profitable way. However, convincing them of the economic viability of the options could be a challenge.
Farmers will give up burning rice straw only if they receive a lucrative incentive. For this there is a suggestion: policy makers can devise a plan to offer incentives to farmers to stop the polluting stubble burning and later credit the incentives through international carbon trading.