DESERTIFICATION INDICATORS AS DIAGNOSIS CRITERIA FOR DESERTIFICATION RISK ASSESSMENT IN EUROPE

Despite the seriousness of the environmental and socio-economic impact s of desertification, few efforts have been made to devise diagnostic and monitoring techniques for appraising the status and trend of deser tification. Indicators are integrated and synthetic information that c an provide data on threshold levels, status and evolution of relevant physical, chemical, biological and anthropogenic processes. Existing s tudies have taken a global perspective, and most have dealt with range land conditions. Moreover, the zones usually studied have included cou ntries whose socio-economic and cultural backgrounds differ from those prevailing in Europe. This paper presents a methodology and discussio n of indicator requirements, selection and definition, procedures for measuring or making estimates, sensitivity, range of values and intera ctions. Emphasizing the need to use indicators to develop a system of desertification evaluation, this paper outlines the advantages and dif ficulties of using such an evaluation system. (C) 1998 Academic Press Limited.