Population and Food

In one line

India fed a population that trebled by raising yield rather than area, and the environmental cost of doing so is one of the environmental problems this paper is about.

In the wording a student can write in an exam: India met the food demand of a rapidly growing population through the Green Revolution of the later 1960s onwards, which raised yield per hectare through high-yielding varieties, chemical fertiliser, assured irrigation, pesticides and mechanisation, supported by assured procurement at a minimum support price. It converted India from a food-importing country to a food-surplus one, and its environmental consequences, being groundwater depletion, soil degradation, loss of crop diversity and the pollution associated with fertiliser and pesticide, are among the pressures this module examines.

What the Green Revolution did

The package. High-yielding dwarf varieties of wheat and later rice, which respond to fertiliser without lodging; chemical nitrogen, phosphorus and potassium; assured irrigation, principally from tubewells; pesticides; mechanised ploughing and threshing; and credit and extension to deliver all of it.

The policy. Procurement of the output at an announced minimum support price, so that the farmer bore no price risk; subsidised fertiliser; and subsidised or free electricity for pumping, which is the single most consequential subsidy in this chapter.

The result. Foodgrain production rose by a multiple, India ceased to depend on imports, and the famine that the neo-Malthusian literature of the period had predicted did not occur.

That last point should be made in any answer about Malthus, because it is the strongest empirical reply to the prediction.

What it cost

Five costs, and each is an environmental problem elsewhere in this book.

Groundwater. The package depends on assured water, and in the absence of surface irrigation that means tubewells. Free or subsidised electricity removed the marginal cost of pumping, and the water table has fallen across large parts of the north-west and the peninsula. That is the subject of the next chapter and it is the largest of the five.

Soil. Continuous cultivation of two irrigated crops a year, without fallow and with declining organic matter, has reduced soil health. Where irrigation has been applied without drainage the result has been salinity and waterlogging.

Crop diversity. A small number of varieties replaced a very large number of local ones. The chapter on ecology explains why that matters: diversity within a species is what allows it to survive a disease or a change in climate, and the Biological Diversity Act 2002 expressly names the conservation of landraces, folk varieties and farmers' varieties among the functions of a Biodiversity Management Committee under section 41.

Fertiliser and pesticide pollution. Nitrogen not taken up by the crop reaches groundwater and surface water; pesticide residues persist.