Integration of satellite remote sensing, simple bioclimatic models and GIS for assessment of pastoral development for a commercial grazing enterprise

Abstract

Satellite imagery, climatic, edaphic and topographic data, and a simple bioclimatic model were used to analyse the pastoral potential of a large cattle grazing enterprise, 'Cooplacurripa', on the central coast of New South Wales. Landsat Thematic Mapper and Spot XS satellite images were processed to create pasture growth status maps describing timbered and cleared areas, and priority areas for phosphorus fertiliser application. A digital elevation model was used to describe slope and aspect, and as a basis for interpolation of monthly surfaces of rainfall, temperature, radiation and evaporation from the Australian Climate Surfaces. These data were combined with a simple growth index model to create production surfaces for tropical, subtropical and temperature pasture types. The property was classified into zones defined by the seasonal growth patterns of the 3 pasture classes. The database was used to identify potential areas for further pasture improvement by a series of logical rules and map overlays to define pasture suitability for currently timbered areas with a slope of less than 20¦. The northern section of the property with the highest rainfall, best suitability for temperate pasture and good road access was chosen for land capability and fauna impact studies on the basis of this analysis. The study provides an example of the application of spatial data to practical management issues in pastoral agriculture.