AMERICAN researchers say governments should require manufacturers to sell nitrogen fertiliser with compounds designed to increase their efficiency and reduce pollution.
They say such a policy could substantially reduce air and water pollution from nitrogen use, including greenhouse gases.
The Princeton University and New York University team estimates using this approach on US corn farms alone could reduce nitrogen pollution by 16 per cent, earn farmers millions of dollars through higher crop yields, and reduce costs of nitrogen pollution by up to US$7 billion.
“Global and US nitrogen pollution have been growing relentlessly, causing ocean dead zones, unhealthy air and large greenhouse gases,” research scholar Tim Searchinger says in a statement.
“Fertilisers contribute greatly to this and will do so more as food production expands. Governments should consider flexible policies that shift more of the responsibility to manufacturers to produce fertilisers with more efficient compounds and continue to innovate for even better compounds.”
Searchinger and David Kanter of New York University recommend a policy similar to US fuel economy rules requiring vehicle manufactures to improve the average fuel use of vehicles.
Globally more than half of the nitrogen applied to crops is lost to the water or air without being used by the crops. This is because nitrogen fertiliser is transformed by microbes in soils in ways that make them susceptible to being dissolved into the air or to runoff in water.