Discrimination between climate and human-induced dryland degradation.

摘要: In this study we present a technique to discriminate between climate or human-induced dryland degradation, based on evaluations of AVHRR NDVI data and rainfall data. Since areas typically have high inter-annual variations has dominant role in determining vegetation growth, minor biomass trends imposed by human influences are difficult verify. By performing many linear regression calculations different periods accumulated precipitation the annual NDVImax, identify period that is best related NDVImax proportion triggered rainfall. Positive negative deviations from relationship, expressed residuals, interpreted as human-induced. We discuss several approaches use either temporally fixed peaking time an absolute one, mean for entire drylands each individual pixel. Advantages disadvantages approach one its combinations discriminating degradation discussed. Depending particular land-use method advantages. To locate with likelihood therefore recommend combining results approach.