Assessment of the effectiveness of desertification rehabilitation measuresin Yulin, north-western China using remote sensing

In China tremendous efforts have gone into the rehabilitation of desertifie d land for productive use such as grazing, crop cultivation and afforestati on. In this study the effectiveness of these agro-ecological measures to co mbat desertification in Yulin, Shaanxi Province of north-western China, is evaluated from multi-temporal aerial photographs in a geographical informat ion system ( GIS). The trend of desertification between 1960 and 1987 is mo delled from changes in other land covers. It is found that desertified area s have decreased by 717.91 ha during the study period as a result of rehabi litation efforts. Plantation of grass is the least effective measure for ha lting sand dune encroachment whereas the planting of shrubs is the most eff ective. The trend of desertification is most accurately modelled from the c hanges in grassland and farmland at an R-2 value of 0.90.