Subsidising Food Crisis
Synthetic fertilisers lead to poor soil and less food

Intensive agriculture, with high use of synthetic fertilisers and chemical pesticides, was introduced in India in the 1960s as part of the Green Revolution. As a result, synthetic fertilisers’ consumption increased from a mere 0.07 million tonnes (Mt) in 1950-51 to a staggering 23.15 Mt in the year 2008-09. This contributed to the growth of food production in the country, but nearly five decades down the line, indiscriminate use of these chemicals has degraded the natural resource base, especially the soil. As a consequence, food production is no longer increasing and is now affected by diminishing returns and falling dividends in agriculture intensive areas.

The synthetic fertiliser usage in the country shows significant variation from region to region. However, in the most agriculture intensive districts (78 districts out of 528 major districts in India), synthetic N-P-K (nitrogen, phosphorus and potassium) fertiliser consumption is more than 200 kg/ha, a rate that is twice the country average. Six crops (rice, wheat, cotton, sugar cane, rapeseed and mustard) consume about two-thirds of the synthetic fertiliser applied. The irrigated area, accounting for 40 per cent of the total agricultural area, receives 60 per cent of the total fertiliser applied.

Synthetic fertilisers are released into the agrarian system at highly subsidised rates. The amount of subsidy outgo on synthetic N-P-K fertilisers (domestic and imported) in India during the last three decades has grown exponentially from a mere Rs. 60 crore during 1976-77 to an astronomical Rs. 40,338 crore during 2007-08. In 2008-09, this rose to Rs 96,606 crores. 

Urea accounts for 82 per cent of the total consumption of nitrogen fertilisers in the country. Several field surveys point to the fact that the huge fertiliser subsidy is one of the main reasons behind imbalance and overuse of synthetic nitrogen fertilisers in India. A majority of the surveyed farmers reported that they used higher doses of nitrogen to replace other nutrients, since as a result of government subsidies, synthetic nitrogen is relatively cheaper to procure. Farmers also expressed their willingness to use more ecological fertilisers if they were easily available and subsidised.
 
Overuse of synthetic nitrogen fertilisers, catalysed by skewed subsidy policies, is causing long-term damage to soil health locally and to the environment at a larger scale (e.g. climate gases and dead zones in the oceans). Soil degradation problems such as soil acidification and alkalisation, as well as deterioration of the soil’s physical properties, such as infiltration, soil aeration, soil structure and bulk density, have all been linked to over emphasis on synthetic fertilizers and neglect of organic fertilization. Several long-term fertiliser trial experiments by the Indian Council of Agricultural Research (ICAR) indicate that the continuous use of synthetic nitrogen alone has resulted in declining yield and has deleterious effects on long-term soil fertility and the sustainability of agricultural systems.

Introspection on results from the multiple long-term fertiliser trials in rice-wheat systems have revealed gradual deterioration of soil health and thus long-term productivity due to overuse and imbalance use of synthetic fertilisers. In Punjab, the state with highest use of synthetic fertilisers in India, data on the relationship between food grain production and fertiliser consumption from 1960 to 2003 show that in spite of consistent increment in N-P-K fertiliser consumption, grain yield has not only practically stagnated but also showed a declining trend with fertiliser application during the later period, 1992 to 2003. Soil degradation, mainly the decline in soil organic matter both in quality and quantity, is one of the major reasons linked to stagnation and decline in yields in most intensive agriculture areas in India.

The response of additional fertiliser application to food grain production has shown a distinct declining trend in recent years: the increased use of synthetic fertilisers no longer contributes to higher soil productivity. The average crop response to fertiliser use was around 25 kg of grain per kg of fertiliser during 1960s, the said value has reduced drastically to eight kg/kg only during late 1990s.  High use of chemical fertilisers is mostly associated with high level of water consumption and micro-nutrient deficiency in soil leading to decline in water table and further deterioration of the soil.

Manufacture and use of synthetic nitrogen fertilisers also contributes significantly to emissions of greenhouse gases, and thus climate change. The total emissions from the manufacture and use of synthetic nitrogen fertilisers represent six per cent of India’s total anthropogenic emissions, comparable to sectors like cement or iron and steel industries, and to emissions from the entire road transport system. There is a significant potential to mitigate these emissions. Savings from the efficient use of nitrogen fertilisers and a shift from synthetic to ecological fertilisation could reduce total emissions from fertilisers in India to 36 Mt of CO2-eq from the current 100 Mt of CO2-eq, and the contribution of fertilisers to the country’s emissions would drop from six to two per cent.

Studies in multiple locations have clearly shown that the deleterious effects of synthetic fertilisers on soil health can be improved by adopting ecological methods of farming and by using low-cost organic alternatives. Application of organic manure appears to be the most important option of sustainable nutrient management programmes under the prevailing Indian conditions, where low organic matter content of soils is a major threat to the maintenance of soil health. Organic matter can improve physical, chemical and biological properties of the soil, while synthetic fertilisers cannot perform any of these roles, apart form supplying a few major plant nutrients.

The amount of nitrogen that could be potentially recovered in organic residues is similar to the total amount of synthetic nitrogen applied to Indian soils every year, ~14 Mt. This highlights the potential feasibility of a complete shift from synthetic to organic nitrogen fertilisation. In addition, recent global meta-analysis have also shown that cover crops such as legumes can provide enough nitrogen to substitute the amount of synthetic nitrogen used worldwide while maintaining the same food production.

The Government needs to

1. Create an alternate subsidy system that promotes ecological farming and use of organic soil amendments.
2. Shift the irrational subsidy policy for synthetic fertilisers to sustainable ecological practices in agriculture.
3. Refocus scientific research on ecological alternatives, to identify agro-ecological practices that ensure future food security under a changing climate.