Abstract: Understanding the impacts of climate change on the distribution of plant species is crucial for the conservation of biodiversity. On the basis of distribution data and environmental variables, we used a maximum entropy model (MAXENT) and GIS tools to estimate the potential distribution range, spatial pattern, and change of Haloxylon ammodendron under reference climate and in 2050 and 2070 (according to the RCP2.6 and RCP6.0 scenarios of IPCC). We obtained the following results: (1) The potential distributions under the reference climate were mainly concentrated in the arid areas of northwest China, especially in Xinjiang: Gurbantunggut Desert, the northern margin and western tip of the Tarim Basin, Alax Left Banner and eastern Alax of Inner Mongolia; Hexi Corridor of Gansu Province; western and northern Ningxia; eastern and southern Qaidam Basin in Qinghai Province. Furthermore, small fragmented patches of suitable area were identified in mngovǐ and Dornogovǐ of Mongolia. (2) Annual precipitation, mean temperature of the wettest quarter, precipitation of the driest quarter and precipitation seasonality (coefficient of variation) mainly limited the distributions of H. ammodendron, and their total cumulative contribution rate was 85.03%. (3) In 2050 and 2070, the range suitable for H. ammodendron would increase significantly, whereas only a few distribution areas in the western tip of the Tarim Basin would fragment and decrease in size. The distribution range and gravity center would shift to northwest and northeast.

Key words: driving factor, MOD17A3, NPP, vegetation, Shaanxi Pro-vince., spatio-temporal change