ECOLOGICAL SURVEYS OF GREAT BRITAIN

The database includes information collected in field surveys of selected 1 km squares of the British National Grid, representative of 32 distinct land classes (classified according to environmental characteristics such as geology, climate derived from maps). Information includes botanical data (occurrence and cover within quadrats), soil type and strata, and land cover, and the data have been collected from up to 508 sample squares, surveyed in 1978, 1984 and 1990. (Countryside Survey 1990, sponsored by the Department of the Environment, the British National Space Centre and the Natural Environment Research Council). The data are regarded as being representative of the land classes and, by classifying every 1 km square of the Nationnal Grid, it is possible to make statistical predictions of the ecological characteristics of each square (see the entry for the Countryside Information System). The national database comprises the land class assignment for each of circa 250,000 1 km squares of the British National Grid together with the characteristics of each land class. The map data are held digitally within Arc-Info GIS and the attribute information and summary data on the land classification are recorded in an Oracle database.