Tuesday, February 3, 2015

Soil fertility-Do the inorganic fertilizers really serve to restore soil health?

The famed green revolution that catapulted India into the major league vis-a-vis grain production had lost its sting long ago and productivity has been stagnating ever since due to progressive decline in soil health. Massive application of inorganic fertilizers did help to increase productivity up to a point and response to these fertilizers is constrained by the poor over all health of the soil caused by intensive cultivation practices. According to many krishi pundits massive subsidies being paid by the government to farmers in the purchase of fertilizers cannot set this distortion right unless farmers take corrective measures to deal with impact of chemicals on micronutrients  and soil acidity. Here is a commentary on this often neglected aspect of modern agriculture.

"Soil fertility, particularly in the northern parts of the country, is steadily declining, thus raising concern for national food security. The situation, according to a Senior Research Fellow of the International Food Policy Research Institute (IFPRI), Mr Shashidhara Kolavalli, is partly the result of some farming practices such as overcropping. "Current agricultural practices 'mine' soil nutrients in the sense that nutrients extracted from soils through crops are not adequately replenished," he stated. The senior fellow was addressing selected journalists on soil fertility management and fertiliser subsidies to Ghanaian farmers. Mr Kolavalli informed the journalists of the arrival of a team of 10 experts in the country to offer recommendations to the government on how to solve challenges associated with offering fertiliser subsidies to farmers. He expressed the hope that the team's exchanges with stakeholders and policy makers would enable the government to structure policies that would address the issues of soil fertility management and fertiliser supply. Following significant increases in world food and fertiliser prices, Ghana and a number of other countries began to subsidise inorganic fertilisers in 2008. The aim was to encourage fertiliser use and also offer uniform prices of the product across the country. However, the cost of subsidies and the quantity of fertilisers attracting subsidies have increased tremendously over the years. Available figures show that a total of GH¢862.39 million was spent on subsidies between 2008 and 2011 by the Ministry of Food and Agriculture (MOFA) and COCOBOD. Meanwhile, the MOFA fertiliser subsidy bill is projected to rise to GH¢136 million and account for over 35 per cent of its budget in 2020. Although inorganic fertiliser was required to replace lost nutrients, Mr Kolavalli said differences in soil characteristics such as active soil organic carbon, micronutrients and acidity might depress crop response to inorganic fertiliser. "The evidence is increasingly indicating that crop response to fertiliser can be significantly constrained by farmers' inability to manage and augment their soils over time."  Mr Kolavalli noted that, "Chemical fertiliser has a role but we cannot just focus on it as the panacea to solving soil fertility problems."

Organic farming may be the right answer to address this problem but where do we go for supply of huge quantities of organic and bio fertilizers to meet the demand if use of chemical fertilizers is to be restrained. Under such a scary situation what will the world at large, do to augment food production to meet the demands of a population expected to burgeon to more than 9 billion by the year 2050? Genetically modified foods are being promoted relentlessly by the genetic engineering industry as a "sure" solution to the stagnation in food production but there is not scientific evidence that GMO route can boost food production to any significant extent. Besides the safety of these unnatural foods obtained by gene manipulation cannot be adjudged absolutely safe based on the present knowledge we have so far. A whole new paradigm shift in the preset practices cannot be postponed further and it is time farmers are retrained to undertake rejuvenation of their farm lands through intervention by the agri varsities where adequate extension personnel are available. Over a period of time sufficient trained field workers must be produced for doing this task on an emergency basis. There seems to be no other option available to the world to stave off large scale scarcity of of essential foods in the coming years. 


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