title: Habitat inventory at a regional scale: a comparison of estimates of terrestrial Broad Habitat cover from stratified sample field survey and full census field survey for Wales, UK.
abstract: Estimates of terrestrial Broad Habitat cover for Wales from the Countryside Survey 2000 stratified sample field mapping programme in Britain are compared with the findings of a full census field mapping project, the Habitat Survey of Wales. The Countryside Survey sampling regime comprised a stratified random sample of 1 km squares [corrected] covering <0.5% of the land surface. Comparative assessment indicates that although few of the sample-derived estimates for individual Broad Habitats are within 30% of the full census survey results, relative extents accord with data from the complete census survey for all Broad Habitats apart from Arable & Horticultural. The accuracy of this estimate is improved when the national boundary of Wales is taken into account in the sample stratification scheme. It is suggested that cultural land-use differences between countries render cropland habitat extent less predictable from physical environmental parameters than semi-natural habitat extent. It is also shown that the precision of sample-derived cover estimates is influenced by habitat pattern: the error term associated with habitats of broadly equal extent is greater for those with the most clumped distributions.
authors.affiliation: Countryside Council for Wales, Maes-y-Ffynnon, Penrhosgarnedd, Bangor, Gwynedd LL57 2DW, UK.
authors.forename: T H
authors.initials: TH
authors.lastname: Blackstock
authors.forename: C R
authors.initials: CR
authors.lastname: Burrows
authors.forename: E A
authors.initials: EA
authors.lastname: Howe
authors.forename: D P
authors.initials: DP
authors.lastname: Stevens
authors.forename: J P
authors.initials: JP
authors.lastname: Stevens
mesh_terms: D003625:Data Collection; D017753:Ecosystem; D014852:Wales