India's agriculture will be badly affected by global warming, but timely action could help mitigate the impact considerably.

Climate change is bound to affect almost all walks of life. But its impact on agriculture will be direct and relatively more pronounced. The production of not only food, vegetables and fruit crops, but also that of livestock and fish can come under severe strain.

The wheat crop has already been the victim of temperature rise in recent years. Other crops and sectors could begin displaying the impact in the near future if measures are not put in place to cope with the menace that has already begun unfolding itself.

Under normal circumstances, the increased concentration of carbon dioxide in atmosphere (called the greenhouse effect) is deemed beneficial for several crops, including wheat, rice, pulses and oilseeds, because it improves photosynthesis (the process of utilisation of solar energy for economic, or edible, produce).

But the deleterious effects of the global warming-induced rise in temperature and the vagaries of weather are likely to more than offset the positive consequences.

A study by the Delhi-based Indian Agricultural Research Institute has indicated that the overall wheat production could drop by 4 to 5 million tonnes with every increase of 1 degree Celsius in temperature throughout the growing season of this crop. The output of other crops, too, would be adversely hit by changes in the climate.

Even minor variations in temperature and rainfall, for instance, could have a significant bearing on the quality of fruits and vegetables, besides that of tea leaves, coffee and aromatic and medicinal produce. This could, in turn, impact the prices and trade of these products.

Recent reports released by the United Nations Inter-governmental Panel on Climate Change have reckoned that India could witness a 10 to 40 per cent loss in crop production due to the rise in atmospheric temperature by 2080-2100. Some other global bodies have also come to similar, albeit scarier, conclusions.

The issue of the impact of climate change on agriculture and the possible ways to cope with it were discussed at a recent meeting of the Parliamentary consultative committee attached to the agriculture ministry. An elaborate note on the subject, put together by the Indian Council of Agricultural Research for this meeting, brings out what can possibly happen and what can be done to combat it.

It points out that temperature rise and other anticipated atmospheric changes could reduce crop duration, increase crop respiration rate, affect equilibrium between crops and pests, lower fertiliser-use efficiency and increase evapo-transpiration. The net result of such changes would be that the water and fertiliser requirement of the crops would increase and the threat from pests and diseases would enhance. The decline of glaciers that sustain river flows could reduce the availability of water for irrigation and other purposes.

Besides, the rise in sea level and sea water temperature could adversely affect fisheries. Many of the precious coral reefs could vanish. Livestock could face heat stress, resulting in a decline in their productivity.

However, the silver lining to this dismal scenario is that it is not impossible to mitigate the impact by suitably adapting to the impending changes. As the official note points out, small changes in climatic parameters can be managed reasonably well by altering the dates of planting, plant density in the fields and input management. Even the projected wheat production loss of 4 to 5 million tonnes could be contained to mere 1 to 2 million tonnes by planting the crop on time and using appropriate varieties.

Besides, crop breeding strategies can be altered to evolve heat-tolerant varieties. Efforts need to be stepped up to improve the photosynthetic capacity of crop plants to make them better converters of solar energy into edible produce by incorporating relevant genes into them. New technologies, including energy and natural resource conservation techniques, can help improve the efficiency of applied inputs like water and fertilisers without sacrificing the yields.

Indeed, the ICAR has launched a national network to study the vulnerability of Indian agriculture to climate change and evolve adaptation strategies to minimise the effect. Some 11 research institutes and agriculture universities have been made part of this network initiative.

However, what is needed urgently is to ensure adequate funding for research and the development of strategies to change agriculture systems in tandem with the changing climatic conditions. The government will also have to come out with policies to help farmers switch over to new farming systems capable of yielding high returns under changed circumstances.