PREDICTING THE DISTRIBUTIONS OF PLANT-SPECIES AT THE REGIONAL-SCALE -A HIERARCHICAL MATRIX MODEL

This paper describes a model which links four levels in an ecological hierarchy using a series of matrices. The four levels are landscape, l and cover type, community and species. Each matrix quantifies the prob abilistic associations between entities in two adjacent levels in the hierarchy. A landscape classification (1 km resolution) provides a spa tial element to the model enabling the distributions of species to be predicted and presented as maps within a geographical information syst em (GIS). Implementation of the model in Northern England is described . The distributions of 579 species of plants were predicted and compar ed with data from independent field surveys. The predicted distributio ns were found to be accurate for 59% of species. The distributions of rare and non-native (introduced) species of plant were relatively poor ly predicted. The potential of this approach to model plant species di stributions is discussed.