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Grassland manuring. Nitrogen loss and efficiency from use of organic manures (Previously NT0301) - NT1404

This study will aim to provide guidance on the efficient use of organic manures, especially cattle slurry and farmyard manure (FYM), as nutrient sources for grassland and forage crops and on the control of nitrate leaching and other nutrient loss pathways. Current strategies for use of cattle slurry for cut grass production and longer term residual effects on N fertiliser requirements and N losses to the environment will be examined. An existing field experiment (conducted at ADAS Trawsgoed) will be extended to include an assessment of residual N effect of cumulative slurry treatments on 2 grass cuts, against a fertiliser N-yield response curve. At another site (ADAS Bridgets), N recovery in grass cut for silage from cumulative applications of cattle slurry and FYM on sandy/shallow chalk soils will also be studied; subsequent release of N from mineralization of organic manure residues, and the effect of nitrate leaching losses and grass response to fertiliser N will be quantified. At 3 additional experimental sites, studies will be conducted to investigate the following: apparent recovery of organic manure N by forage maize; effect of high rate applications of manure on N leaching; and the effect of manure type, application timing and time of incorporation on N losses from a succession of forage maize cropping. Data generated by the study will be related to N cycling as well as fate of manure N in grassland systems following land application. This will be achieved by utilising data from both this study and from project NT1402, in order to develop, validate and improve a manure N model. Results will be communicated in the form of publications in refereed journals, publications in trade journals and presentations to scientists and industry.
Time-Scale and Cost
From: 1995

To: 1998

Cost: £199,363
Contractor / Funded Organisations
Fields of Study
Fertilisers and Nitrate Pollution