Ei. Lord et Sg. Anthony, MAGPIE: A modelling framework for evaluating nitrate losses at national and catchment scales, SOIL USE M, 16, 2000, pp. 167-174
A national agri-environmental database and nitrate modelling system has bee
n developed to support the UK government's nitrate policy development. The
framework, 'MAGPIE', consists of a database and models linked within a Geog
raphical Information System and provides a user interface which allows deta
iled spatial and statistical investigation of the current state (data and m
odel output) and the impact of changes in conditions or agricultural practi
ce. Data on crops and livestock numbers taken from the annual agricultural
census were modified in relation to land cover data derived from remote sen
sing, and other sources. These data and data on climate, soils and altitude
were interpolated to a 1 km grid. The models of nitrate loss were adapted
to work with this data set while retaining as far as possible the salient f
eatures of the more detailed models and data from which they were derived.
The resulting Policy Decision Support System was found to give estimates of
mean annual flow and nitrate load for agricultural catchments which matche
d measured data closely. The system has contributed to work on a number of
policy issues both within the UK and in the UK's contribution to internatio
nal policy development on pollution derived from agriculture.