Past and future influence of climate change on spatially heterogeneous vegetation activity in China

Abstract. Climate change is a major driver of vegetation activity, and thus their complex relationships become a frontier and difficulty in global change research. In this paper, the spatial distribution and dynamic variation of climate change impacts on vegetation activity from 1980s to 2050 in China were investigated by the Geographically Weighted Regression (GWR) model, based on the combined datasets of satellite vegetation index, climate observation and projection, and future vegetation productivity simulation. Our results noted that the significant positive precipitation–vegetation relationship was and will be almost distributed in the north of China, except the northeast and northwest China with significant but varying influence of temperature rising, while the regions with temperature dominated vegetation activity mainly located in the southern part of China. There will be different climatic dominators for vegetation activity in some regions such as northwest China, and even opposite correlation in the northeast China, and further the responding patterns of vegetation activity to precipitation variation will be moving southward in the future three decades. It is indicated that although high warming rate will restrain the vegetation activity, precipitation variability can mediate the hydrothermal conditions for vegetation activity, for example the enhanced vegetation activity in the Tibetan Plateau and the weakened vegetation activity in the East and Middle China in the future. Furthermore, coupling the responding patterns and the dynamic variation, it can be found that during the period from 2021 to 2050, vegetation in most of north China may adapt to an arid environment, while in many southern parts it will be repressed due to water shortage. However, the continuous and dynamic responding process of vegetation activity to climate change will be determined by the spatial heterogeneity in climate change and vegetation cover.