Drought produces a large number of impacts that affects the social, environmental, and economical standard of living in arid regions. Assessing vulnerability for drought is crucial. Legacies of land use activities continue to influence ecosystem structure and function for decades or centuries or even longer after those activities ceased. Extreme climatic event affect community assembly and evolution. We hypothesized that if there is long history of one ecosystem, vulnerability is low for typical land use and extreme climate (drought).

We compared the variation of NDVI at the places with different history of landuse. Rainfed agriculture would be affected by drought strongly; therefore we focus only on rainfed agricultural land in arid regions. Aridity index was calculated to abstract the arid region (0.05 < AI < 0.65). Precipitation and potential evapotranspiration data were from Climatic Research Unit (CRU), University of East Anglia ver.3.10.01, 2012. Anthropogenic biomes (Ellis et al., 2010) was served as the historical landuse data from 1700s. A digital global map of irrigated areas (Siebert and Döll., 2001) was served for avoiding the area of irrigation.