The use of land facets as biodiversity surrogates during reserve selectionat a local scale

Where species distribution data are inadequate reserve selection procedures have to rely on surrogate measures of biodiversity. The informativeness of land facets (the simplest units of a landscape with uniform slope, soils a nd hydrological conditions) as a local scale environmental surrogate was in vestigated in the Venetia-Limpopo Nature Reserve, South Africa. Multivariat e analysis (MDS, ANOSIM) revealed that the land facets adequately represent distinct bird and dung beetle assemblages and are therefore useful surroga tes. These land facets/assemblages were subsequently used as attributes in the following reserve selection procedures: (i) Percentage Area Representat ion (PAR-represent a nominated percentage area of each assemblage); (ii) Sp ecies-Assemblage Representation (SAR-represent each species within the smal lest number of assemblages); (iii) Assemblage Diversity (AD-maximising dive rsity by first selecting areas containing most dissimilar assemblages). The influence of grid cell size, target representation percentages and an over -representation constraint on the efficiency of the algorithms were illustr ated. The SAR procedure did not represent assemblages lacking distinguishin g species and were thus more efficient in terms of total area selected. The AD procedure selected a slightly larger area than the PAR procedure, but w as highly effective at rapidly increasing the diversity of the reserve netw ork. (C) 1999 Elsevier Science Ltd. All rights reserved.