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Improvement of nutrient loss modelling systems and data: national and catchment scale - NT2202

Description
The catchment modelling system is designed to predict nitrate losses to ground and surface waters from agricultural land and to determine the impact of changes in practice or climate on these losses. It uses agricultural census data, the spatial accuracy of which is dependent on the spatial accuracy with which parish boundaries are assigned; however, current parish maps have significant discrepancies. This study will aim to improve the quality of data used by the model by improving the spatial precision of census data. In addition, a regionalised calculation of nutrient balances derived from national crop and livestock-specific nutrient balance estimates will be performed, as will a preliminary regionalised estimate of ammonia emissions. The study will be composed of 3 specific objectives outlined as follows, together with ways in which they might be achieved: 1. Development of a complete link between parish census data and a spatial map of the UK at 1 km resolution or less, and modification of this link to match earlier census data sets. The link will be constructed by amendment of digitised boundaries and cross-referencing between old and new parish identities; 2. Estimation of a set of nutrient balance coefficients, and the classes of crops and livestock to which they refer, and application of these coefficients to England and Wales using data on land use, livestock and environmental conditions. This, together with the map, will allow calculation of nutrient balances for any catchment and data set; and 3. Estimation of a set of ammonia loss coefficients on the basis of land use and livestock numbers using published data and simple models, and application of these coefficients to England and Wales using data on land use, livestock and environmental conditions. This will allow calculation of ammonia emissions for any defined area and data set, and assessment of the uncertainty of estimates. Additional information (e.g. climate, soil type) needed to modify estimates locally will also be determined.
Time-Scale and Cost
From: 1998

To: 1999

Cost: £28,140
Contractor / Funded Organisations
ADAS UK Ltd.
Keywords
              
Fields of Study
Fertilisers and Nitrate Pollution