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To develop strategies to reduce N loss from grassland (New codes NT1602/NT1902) - NT0601

Description
See NT1602/NT1902.


NT0601. Strategies for nitrate pollution control in grasslands.

Practical management strategies are required to reduce the flow of nitrate and other pollutants to waters from grassland production systems, in order to comply with EC directives. This study will aim to investigate factors influencing flow of N from grassland and provide guidelines for its control. N losses from different grassland sites, under various management regimes, will be quantified. An empirical model of N cycling in grassland systems will be developed, tested and extended to mixed farming. Surface run-off and leaching interactions in grassland soils will be quantified, together with N flows into surface and sub-surface aquifers. Techniques will be developed for tactical adjustment of N fertiliser use to minimise nitrate losses, and test-bed grassland N management regimes will be produced to optimise utilisation of N (and other nutrients) in grassland systems. The effects of long-term grassland management will be determined on nitrate release after ploughing and on interactions with denitrification at depth. In addition, interactions between N cycling and losses of other nutrients, such as Ca and P, will be quantified and the use of deep rotting herbage species to scavenge nutrients and reduce leaching will be evaluated. It is anticipated that this research programme will contribute to current understanding of cycling and loss of nitrate and other nutrients from grassland soils, and will provide useful information concerning gaseous emissions (e.g. ammonia, nitrous oxide), atmospheric chemistry and the impact of acid rain.
Objective
Quantification from grassland under different management's over a range of sites Develop and test application of empirical model of N cycling in grassland systems and extend to mixed farming Characterise and quantify surface run-off and leaching interactions in grassland soils and N flows into surface and sub-surface acquifers. Develop and test techniques for tactical adjustment of N fertiliser use to minimise losses of nitrate from grass lands Produce 'test-bed' grassland N management regimes to optimise utilisation of N (and other nutrients) in grassland systems Determine effects of long term grassland management on release of nitrate after ploughing and on interactions with denitrification at depth Quantify the interactions between N cycling and losses and those of other nutrients, e.g P and Ca- Investigate the use of deep rotting herbage species to scavenge nutrients and reduce leaching
Time-Scale and Cost
From: 1991

To: 1995

Cost: £1,488,000
Contractor / Funded Organisations
Institute of Grassland and Environment Research (IGER)
Keywords
              
Fields of Study
Fertilisers and Nitrate Pollution