AI 中文总结
该研究揭示2000年以来中国生长季非均匀水文极端事件急剧增加，其“北湿南干”格局对植被生长造成净负面影响，凸显需加强水文管理以降低风险。
AI 中文摘要
温室变暖下降雨空间非均匀性加剧，意味着可能触发更多非均匀水文极端事件（IHEs），即极端降雨或干旱共存。中国的植被生长对水文灾害敏感，但IHEs的变率及其生态影响仍未得到充分探索。本研究发现，2000年以来中国生长季的IHEs显著增加（每十年增加2.1次或14.52天），过去五年急剧上升至年均6.4次或42.0天。主要驱动因素是水汽-动力耦合天气条件的非均匀性增强，同时伴随气候降水分布的北移。这导致IHEs影响呈现“北湿南干”格局，对中国植被生长造成严重且不对称的威胁，干旱区域扩张对植被的胁迫强于降雨的补偿效应。研究表明，IHEs的急剧上升往往对植被生长产生净负面影响，凸显了加强水文管理以降低未来风险的必要性。
英文摘要
The intensifying spatial inhomogeneity of rainfall under greenhouse warming implies that more inhomogeneous hydrological extremes (IHEs), i.e., coexistence of extreme rainfall or drought, may be triggered. While vegetation growth in China is sensitive to hydrological hazards, the variability of IHEs and their ecological impacts remain underexplored. Here, we find a significant increase in IHEs during China's growing season since 2000 (+2.1 events or +14.52 days per decade), with a rapid sharp rise to an annual average of 6.4 events or 42.0 days in the past five years. The primary driver is the enhanced inhomogeneity of moisture-dynamic coupled weather conditions, overlapping with a northward shift of climatological precipitation distribution. This results in a "Wet-North and Dry-South" pattern of IHE impacts, which poses severe and asymmetric threats to vegetation growth in China, with the expansion of drought areas exerts stronger stress on vegetation than the compensatory effects of rainfall. Our findings suggest that the sharp rises of IHEs tend to yield net negative impacts on vegetation growth, highlighting the need for stronger hydrological management to reduce future risks.
Comments21 pages, 5 figures
