Research to look at reducing nitrogen fertilisers at farms in the warmest regions, to combat air pollution and CO2 emissions A team of US scientists have been granted $500,000 funding to investigate whether or not reducing farm fertiliser use in some of the US' hottest farming regions could improve air quality and cut CO2. The three-year grant has been awarded by the National Institute of Food and Agriculture – part of the US Department of Agriculture – to test the effectiveness of different farming techniques for the use of nitrogen fertiliser. According to the research team, high-temperature agricultural regions are already prevalent in the southern US and other parts of the world, but are set to become even more common globally as a result of climate change. Meanwhile, farms in regions with high temperatures – defined as above 95°F (35°C) – lose "an unusual amount of nitrogen to the air" from common agricultural fertilisers in which the chemical element is prominent. As a result, farmers need to use more fertiliser, which increases their costs. And fertilised soils produce large amounts of nitrogen oxides, which when released into the air play an important role in the formation of the toxic air pollutant ozone as well as greenhouse gas (GHG) emissions. However, a team of scientists led by Darrel Jenerette – a riverside landscape ecologist from the University of California – have been working on a method of modifying agricultural fertilisation and irrigation practices in high-temperature environments, which they claim can reduce losses of nitrogen to the atmosphere by as much as 50 per cent. High-temperature agriculture practices are underappreciated," said Jenerette, an associate professor in the university's department of botany and plant sciences. "It is remarkable how different they can be, compared with agriculture in temperate regions." The research team, which also includes academics from the University of Iowa and California State University, plans to use the funding to conduct measurements of nitrous oxide and nitrogen oxides in fields of the common summertime crops alfalfa and sorghum in the San Joaquin Valley and Imperial Valley in California, where average summer temperatures are around 40°C. Previous work by the scientists in these areas found the Imperial Valley to have some of the highest soil nitrogen oxide emissions ever observed, which they say are capable of influencing regional air quality and making a large contribution to GHG emissions. The research grant follows a recent survey which found more than half of farmers in England do not believe it important to consider greenhouse gas emissions when making decisions about their crops, land management and livestock.