Near‐Earth monitoring of range condition and trend

Abstract

As remote sensing of rangelands moved from aerial photography to satellite imagery with small scales and low resolution, range managers became increasingly aware of limitations imposed by scale. In this paper applications of large scale, near‐earth, low‐altitude, high‐resolution remote sensing technology are considered and definitions provided. Both large scale aerial photography and airborne digital multispectral videography systems are discussed and their utility for measuring rangeland condition and monitoring trend is reviewed. Large scale aerial photography has very high resolution with excellent potential for measuring many features necessary for monitoring rangeland vegetation and soils. Airborne multispectral videography provides near‐photographic resolution with added advantages of instant digitization, independence from film processing, multispectral capabilities and relatively low cost. Both provide information for identification of species and plant communities, their measurement and change detection. This information is useful for determining rangeland trend. Interpretation and analysis of several detailed rangeland features can be accomplished using features identified with these systems, e.g., percent bareground, erosion, rock/pavement/gravel surfaces, soil color, shadow, cryptogamic cover, dry annual vegetation, and the greenness, grayness or yellowness of perennial grasses and shrubs.