THE SENSITIVITY OF SURFACE WATERS OF GREAT-BRITAIN TO ACIDIFICATION PREDICTED FROM CATCHMENT CHARACTERISTICS

Using a combination of soil, land use and geological information, a ma p of Great Britain has been derived which indicates the sensitivity of surface waters to acidification. For the geological information, a sl ightly modified version of an available map was used which indicated t he sensitivity of groundwaters to acidification. For soils, 1-km datab ases of soil information for England and Wales and for Scotland were e mployed to map the soil sensitivity as determined by buffering capacit y. The derived soils map was modified to take account of agricultural liming in arable and managed grassland areas using the ITE Land Classi fication. The final map of surface water sensitivity was obtained by u sing a geographic information system overlay procedure which enabled e ach combination of soil and geology sensitivity to be uniquely defined . The final sensitivity classification was based upon expert knowledge and the experience of a similar sensitivity mapping exercise for Wale s.