The intensification of the hydrological cycle has altered the spatiotemporal redistribution of terrestrial water storage (TWS). The long-term evolutionary mechanism controlling global TWS droughts and their bivariate risks (i.e., drought and severity) remain uncertain. Using machine learning-based TWS reconstructions, we explored the drivers, changes, and impacts of TWS droughts during 1940-2022 at the global scale. We developed a machine learning framework to detect the dominant climate/vegetation factors governing TWS. During 1940-1970, precipitation and vapor pressure deficit were the primary factors influencing TWS; however, the leaf area index was the dominant factor during 1992-2022. We evaluated past changes in drought frequency, duration, severity, and intensity, and found a substantial intensification tendency in most land areas. Subsequently, we evaluated the bivariate risks by combing a copula-based modeling approach and the most likely realization method, revealing a fivefold intensification over most regions. Changes in the marginal distributions of duration and severity accounted for 40-60% of the overall changes in bivariate drought risk, while the contribution from their dependence varied globally. Approximately 80-90% of the global population and gross domestic product were exposed to increasing bivariate drought risk, indicating the need to improve the adaptivity of society and ecosystems to climate change.

采用青海省1965—2018年50个气象站月降水资料和同时段太阳黑子相对数资料,将青海省划分为长江和澜沧江源区、黄河源区、东部低海拔区和柴达木盆地区,运用集中度和集中期、线性倾向估计、M-K检验法和Morlet小波分析法对青海省时空降水变化特征进行分析.结果表明:青海省降水量在空间分布上呈现由西北向东南增加的特征,在年际变化上,青海省和4个分区年降水量都具有上升趋势,其中青海省平均上升0.81 mm/a;青海省降水年内分配不均,降水集中度具有逐渐趋向均匀的趋势;青海省出现微弱的降水突变信号,青海省主体和东部低海拔区突变始于2006年前后,长江和澜沧江源区突变始于2003年前后,柴达木盆地区突变于2001年前后,而黄河源区存在4个可能突变点;柴达木盆地降水变化具有22～23 a的主周期,青海省和其他3个分区都具有28～30 a的主周期,在28 a尺度上青海省和4个分区降水量与太阳黑子相对数的小波系数都分别达到了0.95、0.86、0.91、0.93和0.75的正相关性,且显著性水平均为0.01.

开展安徽省江北产业集中区污水处理厂入河排污口设置论证,目的在于合理开发利用与保护水资源,保障水域生活、生产和生态用水安全,为各级水行政主管部门审批入河排污口以及建设单位合理设置入河排污口提供科学依据.经过现场查勘、资料收集整理及补充监测,根据排污口位置所涉及江段的水文水质、水生态、水功能区划成果及取排水状况,分析了废污水排放的受纳水体(长江)水质和水生态环境状况.本文结合水功能区划,采用MIKE21数学模型模拟的方法,对排污口设置后废污水排放进行了模拟预测,论证分析了排污口设置对受纳水体水质和水生态环境的影响,以及对有利害关系的第三者产生的影响,并对排污口设置的可行性和合理性进行了分析.

abcd水量平衡模型在国外得到了广泛应用,但在国内应用基本处于空白状态.为了探究该模型在我国中小流域应用的适应性及有效性,在介绍abcd模型的原理及结构的基础上,将其应用于新安江流域的径流预报模拟.在国内首次对abcd模型的4个参数进行敏感性分析,采用单变量法和多变量法分别探讨模型的性能指标对参数变化的响应程度.结果 表明:校验阶段汛期与非汛期Nash确定性系数(Nash-Sutcliffe efficiency,NSE)分别为0.929和0.863,表明拟合程度较高;参数敏感性分析对于提高abcd模型参数率定的效率和精度具有显著意义;单变量法与多变量法结果相近,NSE对参数c最为敏感.通过对比径流模拟值与实测值,得出该模型模拟精度高、具有较高的适应性,能够广泛应用于我国中小流域.