If we are to believe the rhetoric of the great agricultural reformers writing at the end of the 19th century, the answer is nothing. But here the witness of other times and places should not be ignored. In India there is now considerable debate about the future of farming as international conglomerates aggressively push forward monocultural practices using high-yield crops underpinned with the use of agrochemical fertilizers. This is threatening not only the livelihoods of smallscale farmers but also having an immediate and deleterious impact on the ecosystem itself.

This apparent ‘need’ for chemical fertilisers to feed the large proportion of the world's human population is now the major source of nitrates in the environment. As a result of all this release of nitrogen compounds, the natural cycle of nitrogen in the environment has become swamped by what is called the ‘nitrogen cascade’ (Galloway et al., 2003).

This is having considerable environmental impact. As we saw in chapter 2, nitrous oxide is a significant greenhouse gas but there are also other environmental effects, as outlined in the following slide:

The increased use of nitrogen compounds in agriculture is also indirectly implicated in:

• marked increase in the incidence of asthma in many developed countries.

• the formation of algal bloom which ‘choke’ lakes, rivers and streams. The blooms may contain a type of bacteria, called cyanobacteria, which produce toxins, killing water life and posing a threat to people

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