Datasets for the graphs of the paper (Fig. 2 to Fig. 7)

Investigating the relationship between factors (climate change, atmospheric CO2 concentrations enrichment, and vegetation structure) and hydrological processes is important for understanding and predicting the interaction between the hydrosphere and biosphere. The Integrated Biosphere Simulator (IBIS) was used to evaluate the effects of climate change, rising CO2, and vegetation structure on hydrological processes in China at the end of the 21st century. Seven simulations were implemented using the assemblage of the IPCC climate and CO2 concentration scenarios, SRES A2 and SRES B1. Analysis results suggest that (1) climate change will have increasing effects on runoff evapotranspiration (ET), transpiration (T), and transpiration ratio (transpiration/evapotranspiration, T/E) in most hydrological regions of China except in the southernmost regions; (2) elevated CO2 concentrations will have increasing effects on runoff at the national scale, but at the hydrological region scale, the physiology effects induced by elevated CO2 concentration will depend on the vegetation types, climate conditions, and geographical background information with noticeable decreasing effects shown in the arid Inland region of China; (3) leaf area index (LAI) compensation effect and stomatal closure effect are the dominant factors on runoff in the arid Inland region and southern moist hydrological regions, respectively; (4) the magnitudes of climate change (especially the changing precipitation pattern) effects on the water cycle are much larger than those of the elevated CO2 concentration effects; however, increasing CO2 concentration will be one of the most important modifiers to the water cycle; (5) the water resource condition will be improved in northern China but depressed in southernmost China under the IPCC climate change scenarios, SRES A2 and SRES B1.

探究气候变化、大气CO₂浓度富集与植被结构等因子与水文过程之间的关联，对于理解和预测水圈与生物圈间的相互作用具有重要意义。本研究采用生物圈集成模拟器（Integrated Biosphere Simulator, IBIS），评估21世纪末气候变化、CO₂浓度升高以及植被结构对中国区域水文过程的影响。研究基于政府间气候变化专门委员会（Intergovernmental Panel on Climate Change, IPCC）排放情景特别报告（Special Report on Emissions Scenarios, SRES）的A2与B1情景组合，共开展7组模拟试验。分析结果显示：（1）除中国最南部区域外，气候变化对我国多数水文分区的径流蒸散发（ET）、蒸腾作用（T）及蒸腾比（蒸腾量/蒸散发量，T/E）均呈现增强效应；（2）CO₂浓度升高在全国尺度上会提升径流量，但在水文分区尺度上，其引发的生理效应取决于植被类型、气候条件与地理背景信息，在中国干旱内陆区则表现出显著的负向效应；（3）叶面积指数（Leaf Area Index, LAI）补偿效应与气孔关闭效应分别是干旱内陆区与南部湿润水文分区径流变化的主导影响因子；（4）气候变化（尤其是降水格局变化）对水循环的影响幅度远大于CO₂浓度升高的影响；不过，CO₂浓度升高仍将是影响水循环的关键调控因子之一；（5）在IPCC的SRES A2与B1气候变化情景下，中国北方地区的水资源状况将得到改善，而中国最南部区域的水资源状况则会恶化。