【摘 要】
：
The Yangtze River Watershed in China is a climate change hotspot featuring strong spatial and temporal variability;hence,it poses a certain threat to social development.Iden-tifying the characteristics of and regions vulnerable to climate change is signif
【机 构】
：
Institute of International Rivers and Eco-security,Yunnan Key Laboratory of International Rivers and
论文部分内容阅读
The Yangtze River Watershed in China is a climate change hotspot featuring strong spatial and temporal variability;hence,it poses a certain threat to social development.Iden-tifying the characteristics of and regions vulnerable to climate change is significantly im-portant for formulating adaptive countermeasures.However,with regard to the Yangtze River Watershed,there is currently a lack of research on these aspects from the perspective of natural and anthropogenic factors.To address this issue,in this study,based on the temper-ature and precipitation records from 717 meteorological stations,the RClimDex and random forest models were used to assess the spatiotemporal characteristics of climate change and identify mainly the natural and anthropogenic factors influencing climate change hotspots in the Yangtze River Watershed for the period 1958-2017.The results indicated a significant increasing trend in temperature,a trend of wet and dry polarization in the annual precipitation,and that the number of temperature indices with significant variations was 2.8 times greater than that of precipitation indices.Significant differences were also noted in the responses of the climate change characteristics of the sub-basins to anthropogenic and natural factors;the delta plain of the Yangtze River estuary exhibited the most significant climate changes,where 88.89％of the extreme climate indices varied considerably.Furthermore,the characteristics that were similar among the identified hotpots,including human activities(higher Gross Do-mestic Product and construction land proportions)and natural factors(high altitudes and large proportions of grassland and water bodies),were positively correlated with the rapid climate warming.
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