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Nitrate leaching risk from livestock manures (Previously NT0310) - NT1410

This study will build on existing work examining the risks of nitrate leaching associated with the recycling of organic manures to agricultural land. The study will be composed of 3 specific objectives outlined as follows, together with ways in which they might be achieved: 1. Assess the long term effects of annual applications of cow slurry or farmyard manure (FYM) on nitrate leaching and nitrogen availability in grassland. Nitrate leaching losses and crop N recoveries will be measured and compared from accumulative applications of cattle slurry and FYM applied annually and at different times of the year. The N value of these manures and N release when applied over several years to grassland and the effect on nitrate leaching and responsiveness of N fertilisers will also be measured; 2. Determine leaching of nitrate following autumn and winter application of animal manures to grassland. Risks of nitrate leaching losses from animal manures applied during autumn and winter on light sandy soil will be assessed, and periods during which various types of manures should not be applied to grassland in nitrate vulnerable zones will be defined. Recovery of N from manures applied at different times to grassland and the effect on soil mineral N residues will also be assessed; and 3. Examine leaching of nitrate following autumn and winter applications of animal manures. Similar studies will be conducted to those outlined in the previous objective, but will be applied to arable cropping rather than grassland. The benefits of catch crops in minimising nitrate leaching losses from autumn and winter applied manures will be assessed. Results obtained in the initial stage of the study have already confirmed the significance of organic manures in contributing to the nitrate problem; the extra information provided by this study will increase confidence in interpretation of the data and will hopefully extend the range of climatic conditions experienced following unusually dry autumns and winters in the initial stage of the work.
Time-Scale and Cost
From: 1994

To: 1997

Cost: £172,137
Contractor / Funded Organisations
University - Harper Adams Agricultural College
Fields of Study
Fertilisers and Nitrate Pollution