Study Region: Jinsha River Basin (JRB), situated in the upper sections of the Yangtze River basin, China Study Focus: The Jinsha River Basin (JRB), renowned as the world's largest hydropower base. In this study, we proposed a novel approach for separating the reservoir's influence on streamflow and the response mechanisms in diverse watersheds. We integrated XGBoost (the eXtreme Gradient Boosting), CNN-LSTM (Convolutional Neural Networks, Long Short-Term Memory) and Informer with 6 hydrological stations data for streamflow reconstruction. Traditional hydrological model SWAT (Soil and Water Assessment Tool) served as a benchmark. New Hydrological Insights for the Region: Reservoir groups were exerting average 40.7 % influence on streamflow after 2010, altering the streamflow with maximum 20 % in the upstream, 42 % midstream and 60 % downstream in August in JRB. Also, reservoir regulation significantly shifted the seasonal streamflow pattern (especially low water season) in the JRB. Under extreme wet (SDI >= 2) in flood season (June-November), the maximum reservoir regulated streamflow offsetting varied between 14.3 % and 28.6 % (2000-4000 m3/s out of Qmax=14000 m3/s). Conversely, under extreme drought (SDI <=-2) in the low water season, reservoir regulated streamflow accumulation accounted for 25-44.4 % (100-800 m3/s out of Qmax=1800 m3/s). Moreover, the XGBoost model can provide a new way for streamflow reconstruction and forecast, particularly in the quantification of the reservoir groups under climate change. Reservoir storage efficiency was more obvious in the midstream, especially after 2015 (with normalized difference (Sreconstruction-Sobservation)> 0 more frequent), while released more in the downstream after 2010 (with normalized difference<0 more frequent). The streamflow reconstruction simulation had a stronger correlation with the catchment streamflow than large-scale atmospheric circulation indices. In summary, our study demonstrates models forecast reliability in streamflow reconstruction under climate change and reservoirs, providing a new reasoning approach for extreme streamflow event early warning resulting from large reservoir operations.

为客观评价特定地区的生物质能源生产潜力,以宁夏为例,考虑到当地有限的耕地资源和稀缺的水资源,选取适宜在宁夏边际土地上种植的3种能源作物(甜高粱、菊芋、柳枝稷);并依据当地的天然降水、能源作物的需水特征和能源产量理论最低需水量,确定能有效提高当地的生物质能源生产潜力的能源作物组合,定量计算宁夏生物质能源的最大生产潜力.结果表明:1)宁夏边际土地总面积为31305.49 km2,占宁夏全区的62.13％,主要分布区域为宁夏中部和西南部,其中适宜种植甜高粱、菊芋、柳枝稷的边际土地面积依次分别为25053.82、21287.12、3900.54 km2;2)甜高粱和菊芋能源作物组合可有效提高宁夏的生物质能源生产潜力.在无人工灌溉的情况下,宁夏生物质能源的最大生产潜力每年可达10.93×107 GJ.

近年来,海河流域滨海湿地退化现象严重,为科学合理地对其实施恢复和保护,须探究湿地退化的影响因素,辨识主要退化成因.广泛收集关于海河流域滨海湿地退化评价的实证研究案例,采用集萃法中的Meta-regression模型,对湿地退化因素及其影响程度进行了综合性的对比与分析.结合57个研究案例,提取525个观察值,筛选出自然和人为两类共9种退化影响因素,通过模型拟合得到各因素对湿地退化的影响程度.模型结果显示:海河流域滨海湿地的退化受到人为与自然因素的双重影响.人为因素中,水资源开采(1.512)、水质污染(0.813)、水产养殖(0.593)、围垦与建设占用(0.436)对湿地退化均为正效应,政策法规(-1.202)呈负效应;自然因素中,降水量(-0.788)与河流径流量(-1.176)对湿地退化呈显著负效应,气温(0.037)与生物多样性损失(0.072)呈较弱的正效应.海河流域滨海湿地的退化影响因素按照影响程度大小排序为:水资源开采>政策法规>河流径流量>水质污染>降水量>水产养殖>围垦与建设占用>生物多样性损失>气温,湿地退化的核心成因在于湿地水资源的补给与存蓄受到了威胁.据此建议,海河流域滨海湿地的恢复与保护应优先解决水源问题,同时应加强相关政策、规划和法律的制定与执行.

To protect ecologies and the environment by preventing floods, analysis of the impact of climate change on water requires a tool capable of considering the rainfall-runoff processes on a small scale, for example, 10 m. As has been shown previously, hydrologic models are good at simulating rainfall-runoff processes on a large scale, e.g., over several hundred km2, while hydraulic models are more advantageous for applications on smaller scales. In order to take advantages of these two types of models, this paper coupled a hydrologic model, the Xinanjing model (XAJ), with a hydraulic model, the Graphics Processing Unit (GPU)-accelerated high-performance integrated hydraulic modelling system (HiPIMS). The study was completed in the Misai basin (797 km2), located in Zhejiang Province, China. The coupled XAJ–HiPIMS model was validated against observed flood events. The simulated results agree well with the data observed at the basin outlet. The study proves that a coupled hydrologic and hydraulic model is capable of providing flood information on a small scale for a large basin and shows the potential of the research.

<span id="ChDivSummary" name="ChDivSummary" class="abstract-text">为准确测算现有农业生产科技水平下的中国粮食生产能力,以2012—2016年最新粮食作物审定品种的区域试验产量为基础,构建测度模型,估算中国（不包括香港和澳门特别行政区及台湾省）耕地粮食的育种生产能力,测算中国耕地粮食产量差（增产潜力）及生产能力开发程度,并分析省际差异规律。结果表明:1)中国现有耕地粮食生产能力是8.46×10⁸ t,实际粮食产量是5.48×10⁸ t,差值达2.98×10⁸ t,占粮食实际产量的54.38%,耕地生产能力开发率为0.63,说明中国耕地粮食潜力有待进一步挖掘。2)中国耕地粮食总生产能力和潜力较大的省市自治区是:黑龙江省、河南省、山东省、河北省、吉林省、安徽省、内蒙古自治区、江苏省、湖南省、四川省、辽宁省、湖北省、云南省和江西省,应作为未来耕地保护和农田建设的重点对象,可通过土地整治和栽培技术等手段,提高耕地质量。3)同时,开发耕地生产潜力需因地制宜,实现提高粮食产量和保护生态的平衡。在江西省、福建省和浙江省,建议加大农田基础设施建设,提高耕地生产能力;在河北省,需提高水资源利用率,实现节水保粮;在宁夏回族自治区、甘肃省和陕西省,需协调农业-能源-水资源关系,实现绿色可持续发展;在广西壮族自治区、贵州省和云南省,可以利用气候优势,在缓坡丘陵区种植茶树、花卉,发展特色农业;在内蒙古自治区、西藏自治区和青海省,不建议过度开发粮食生产潜力。</span>

Due to natural change and special human destruction, the area of wetland is greatly decreasing. To recover the wetland ecological system has become an urgent task that must be faced. Water plays an important role in the course of wetland recovery. With Yongnian wetland as a case study, the ecological function method was used, based on structures and functions of the wetland ecological system, the ecological water requirement was divided into four parts: water requirement of wetland vegetation, water requirement of wetland soil, water requirement of wildlife habitats and water requirement of recharging ground water. According to the indexes that were presented in the paper, each part was classified to three grades, respectively. According to the formulas that were given in the paper, all kinds of ecological water requirement of Yongnian wetland were calculated; the results showed that the least ecological water requirement is 1.256 × 108 m3. The proper ecological water requirement is between 3.041 × 108 m3 and 4.301 × 108 m3, and the most ecological water requirement is 6.350 × 108 m3.

为提升水资源配置效率,应用数据挖掘技术,对全国首次重点用水单位监控工作中所获得的约26万个用水数据进行了特征选择和用水模式区分.依据DB index准则,从用水特征中筛选出现状、愿景和波动3个特征.从这3个特征入手,采用k-means算法,将用水主体划分为5种用水模式,即均衡扩张型、均衡紧缩型、集中稳定型、波动收缩型和波动扩张型.结果 表明:全国大多数用水单位现状特征集中在[0.7,0.9]、愿景特征集中在[0.8,1.0]、波动特征集中在[0.1,0.5],较内地用水,东南沿海用水量在年内各月间波动较小.用水模式以波动收缩型为主,该模式涵盖多数产能过剩的高耗水行业;农业的用水模式为集中稳定型;高新技术与服务业的用水模式多为波动扩张型与均衡扩张型.结合不同的用水特征和用水模式,在法律、制度、监控等层面分别提出了管理建议,可为精准化、差异化节水管理提供参考.

Inter-basin water transfer projects are widely used in water-stressed areas. North China is facing severe imbalance between water demand and water supply. The South-to-North Water Diversion (SNWD) Project was built to transfer water from the Yangtze River Basin to the Hai River Basin. The Fuyang River Basin in the southern part of the Hai River Basin, passing through the Handan city, was chosen as the study area. To identify the effects of the SNWD Project on the water-receiving area, this paper used the decision support system AQUATOOL to simulate the water-dispatching scheme while using the water from the SNWD Project for domestic need in different level years. The results indicate that the SNWD Project provided 128.32 × 106 m3 of water in a wet year, 109.88 × 106 m3 in a normal year and 135.14 × 106 m3 in a dry year to this area. The added quantity of recycled water is 56.75 × 106 m3, 50.59 × 106 m3 and 57.52 × 106 m3, respectively. The water shortage in normal years was covered by the SNWD Project and the water shortage in dry years was reduced by 62.4%. Local environment was improved because of the SNWD Project, i.e., the SNWD water replaced and reduced the use of groundwater and increased the inflow to the Fuyang River and the Yongnian Wetland by increasing the recycled water. This research has demonstrated the SNWD Project has started to play a key role in securing water use and improving the environment in the water-receiving area since its completion in 2014.

This paper reviews the cognitive processes of uncertainty and equifinality to understand the idea debates on hydrological models.It briefs various doctrines on uncertainty sources,summarizes the supporting and opposing views of the discussion and analyzes the hotspots and trends of relevant research work.It also conducts an analysis on the equifinality of hydrological model in terms of academic background,research progress,main achievements and challenges faced.In the regards of the four-source doctrines,hydrology marginalization,minority views and equifinality,it comments on different points of view concerning uncertainty and equifinality and gives some reflections on the epistemology and methodology adopted by different research schools.

Given the substantial impacts that are expected due to climate change, it is crucial that accurate rainfall–runoff results are provided for various decision-making purposes. However, these modeling results often generate uncertainty or bias due to the imperfect character of individual models. In this paper, a genetic algorithm together with a Bayesian model averaging method are employed to provide a multi-model ensemble (MME) and combined runoff prediction under climate change scenarios produced from eight rainfall–runoff models for the Yellow River Basin. The results show that the multi-model ensemble method, especially the genetic algorithm method, can produce more reliable predictions than the other considered rainfall–runoff models. These results show that it is possible to reduce the uncertainty and thus improve the accuracy for future projections using different models because an MME approach evens out the bias involved in the individual model. For the study area, the final combined predictions reveal that less runoff is expected under most climatic scenarios, which will threaten water security of the basin.

Conflicts between water supply and water demand are intensifying in irrigation districts along the Lower Yellow River, China, due to climate change and human activities. To ensure both adequate food supply and water resource sustainability in the region, this paper investigated the relationship between wheat yield and meteorological variables in 7 provinces within the Yellow River Basin. The key meteorological variables that influenced wheat yield were identified, and the regression functions between climate relevant wheat yield and these variables were established. Combining with the climate change scenarios in the future, the impact of climate change on crop yield were assessed. To cope with limited water resources in this region, it is necessary to properly irrigate crops based on soil water content and take full advantage of precipitation and surface runoff during the summer maize season.

To simulate flood processes at the basin level, the GPU-based High-Performance Integrated Hydrodynamic Modelling System (HiPIMS) is gaining interest as computational capability increases. However, the difficulty of coping with rainfall input to HiPIMS reduces the possibility of acquiring a satisfactory simulation accuracy. The objective of this study is to test the sensitivity of the surface runoff coefficient in the HiPIMS source term in the Misai basin with an area of 797 km2 in south China. To achieve this, the basin was divided into 909,824 grid cells, to each of which a Manning coefficient was assigned based on its land use type interpreted from remote sensing data. A sensitivity analysis was conducted for three typical flood processes under four types of surface runoff coefficients, assumed a priori, upon three error functions. The results demonstrate the crucial role of the surface runoff coefficient in achieving better simulation accuracy and reveal that this coefficient varies with flood scale and is unevenly distributed over the basin.

近年来,我国城市内涝灾害频发,对城市交通造成了巨大的负面影响.以邯郸市为研究对象,使用空间分析软件Arcgis处理其土地利用数据,将处理过的空间属性数据输入城市暴雨管理模型SWMM,模拟城市雨洪过程,计算城市区域淹没水量,并实现其可视化,绘制不同降雨条件下的邯郸市内涝交通风险等级分布图,并进一步对内涝区域的分布特征进行分析.分析结果表明,邯郸市内涝严重区域的面积随降雨强度增大急剧增加,邯郸市现有排水体系的内涝防治系统无法应对当前20年一遇的洪涝灾情,城市路口的内涝交通风险高于当地平均风险水平.基于此,本文提出改变地表覆被情况、增设蓄水池、改善城市排水系统等可行性建议,对内涝风险灾害预警及其防治具有一定的借鉴和参考价值.

湿地的恢复与保护是近年来环保领域的热点.用历史视角研究湿地及其周边的演化历程,能极大地丰富对湿地的认识,使湿地的恢复和保护更有针对性.本文以华北地区典型的受高强度人类活动长期影响的自然湿地永年洼为例,尝试从历史视角审视其演变,证明这一方法的有效性,并指出:①广府古城的历史长于永年洼的历史,永年洼始终受高强度人类活动影响;②永年洼在1949年以后的剧烈萎缩主要是因为水利工程控制来水量和围垦造田,永年洼仍具备成为湿地的条件;③永年洼以防洪功能为主、生态功能为次,永年洼的恢复保护应借建设湿地公园的契机,保障湿地来水的水量和水质.

This study concerns the management functions, institutional and legal frameworks to foster IRBM in the Yangtze River Basin. It is implemented as part of the EU China River Basin Management Programme funded by the EU.The overall objective of the study is to contribute to an enabling framework of policies, legislation and institutions that will promote IRBM in China and assist the government to harmonise social and economic development and water and environmental protection within the Yangtze River Basin. Specifically, the study will provide the CWRC with a better basis for informed decisions on adjustment of its organization, responsibilities and management functions to be incorporated in the Yangtze River Master Plan. Based on stakeholder mapping an assessment has been made to characterise the present situation of water resources management in China and provide direction for future changes. The assessment found that 1) China has established a legal framework supporting water management in a river basin context, 2) plans embodying IRBM are drafted at national, river basin and provincial levels, and 3) the existing funding of water management is dominated by government investment. A diagnosis and evaluation of the management functions of the CWRC is presented with focus on gaps and overlaps providing recommendations for a more effective governance structure in accordance with internationally accepted principles that have emerged during the past 10 years. The diagnosis is based on key informant interviews and questionnaires and indicated that 1) Chinese legislation enables decentralized river basin management, 2) river basin, regional and provincial management functions are not clearly defined, 3) some management functions of the CWRC are difficult to implement due to discrepancies between authority and responsibilities 4) there are no efficient consultation and coordination mechanisms among stakeholders within the river basin, 5) the implementation of IRBM lacks support of provincial and local authorities, and 6) the CWRC sees stakeholder participation as the key to better river basin governance. Water management in the Yangtze River Basin has been analysed with the Rhine River, Danube River, France and the European Union as reference. The comparisons indicate that 1) legislation or formal agreements between different administrative units, nations or provinces, are required for efficient cooperation, 2) an inter-provincial river basin organization is an ideal platform to promote IRBM and resolve conflicts between nations or provinces within a river basin, 3) political governance and technical support should be separated, 4) stakeholder participation is imperative for efficient IRBM, and 5) pollution of the Yangtze River is at risk of increasing while the Rhine River and to some extent the Danube River have passed a turning point (top of Kuznet’s curve), where pollution is effectively managed and declining.Strategically institutional arrangements for IRBM will be conditional on central government initiative. At the national level four initiatives are proposed as umbrella for basin level action, 1) a national water framework plan to be inspired by the EU Water Framework Directive (WFD), 2) an assessment of basin institutional arrangements inspired by the Rhine and Danube rivers, 3) an assessment of provincial institutions inspired by France and 4) an assessment of legal efficiency taking the EU WFD as benchmark.In close consultation with the CWRC an action plan to foster IRBM in the Yangtze River Basin has been formulated in terms of legislation, institutions, capacity building, financing, information disclosure and stakeholder participation.The principal recommendations of the study are:1) Water Law to be amended or supplemented with legislation, which clearly defines the division of responsibilities between the national, river basin and provincial level authorities.2) A National Water Resource Commission to be established to strengthen cross-sectorial coordination and cooperation and mitigate the current fragmentation of responsibilities, especially the overlapping responsibilities of the Ministry of Water Resources (MWR) and Ministry of Environmental Protection (MEP) in water pollution management and of the Ministry of Water Resources and Ministry of Land and Resources in groundwater management.3) Reform of the CWRC may take one of three basic models: Unified management as branch of central government, essentially the current structure; Coordinated management governed by stakeholders, including central government; Autonomous enterprise authorised by central government.4) Institutions and responsibilities for water resources management and water service delivery to be separated and clearly defined.5) River basin commissions to be assigned responsibility for coordination of water resources management at basin scale and provinces for implementation in accordance with overall management objectives.6) River basin commissions to be responsible for operation of multipurpose infrastructure and bulk water supply.7) Provinces and municipalities to be the responsible for management and delivery of water supply and sanitation services in both rural and urban areas.8) Cost recovery for water resources management, bulk water supply, water supply and sanitation services to be scaled up and serve as water demand management tool as well as a significant source of funding for infrastructure development.9) National Water Resources Council to be set up at national level to supervise and regulate water resources management and services delivery by benchmarking of river basin commissions, provincial administrations and water utility companies using clear and well defined performance indicators. 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Land use/cover change (LUCC) is one of the crucial factors influencing the hydrological process, thus the flood characteristics in time and space. Therefore the evaluation of the change of flood characteristics implies an integrated analysis of LUCC and hydraulic simulation. In this study, the effect of LUCC on flood is examined based on an approach composed of three parts: (1) reproduction of spatially explicit LUCC; (2) application of a 2D hydraulic modelling for flood simulation; (3) demonstration of results for Beijing. The approach is applied to a flood-prone area in Beijing. The results show that 8% and 21% of the study area experienced LUCC during 1991–2001 and 2001–2011, respectively, and these changes greatly influenced the characteristics of the 20-year flood, i.e.: (1) the flood zone is doubled during 1991–2001 and about four-fold during 2001–2011; (2) the water depth is increased for most of the study area; and (3) the flow velocity becomes faster. It indicates that flooding still exists within Beijing and is even more dangerous than 40 years ago and suggests that actual land use pattern and existing flood protection works should be re-evaluated regarding the flood characteristics change due to LUCC.

In this study, a mix inexact-quadratic fuzzy water resources management model of floodplain (IQT-WMMF) has developed, through incorporating techniques of credibility-constrained programming (CP), two-stage programming (TP), interval-parameter programming (IPP) and quadratic programming (QP) within a general framework for limited data availability. The IQT-WMMF can provide an effective linkage between system benefit and the associated economic penalty attributed to the violation of the pre-regulated water target under limited data availabilities expressed probabilistic distributions and interval values; meanwhile, imprecise and no-linear economic data would be resolved. The developed method is applied to a real case of planning water resources in the Dahuangbaowa floodplain, China, with the aim to develop a sustainable water resources management in the study region. A number of scenarios with wet land expansion strategies under various credibility levels are analyzed, implying that different policies can lead to varied water-allocation patterns, system benefits, and system-failure risks. The results discover that water deficits and flood damages have brought negative effects on economic development synchronously, which need to effective plans to reduce losses of shortages and floods for achieving higher system benefits. Tradeoffs between economic benefit and system-failure risk can support generating an increased robustness in risk control for water resources allocation under uncertainties, which is beneficial to adjust the current water-allocation sustainably.

GR3模型结构简单,只有3个可自动优选的参数,已在欧洲、非洲、南美等地取得理想的应用效果.为验证其在我国的适用性,特选择分布于长江、黄河、淮河、松花江水系的7个代表流域,与国内普遍应用的三水源新安江模型进行对比.结果表明,GR3模型可媲美新安江模型,在我国具有相同的适用性.

GR3 has a simple structure, a parsimonious number of parameters which are easy to be calibrated. It is a lumped and conceptual hydrological model for rainfall-runoff simulation. In order to test its applicability in China, seven representative basins were selected from the river systems of the Yangtze, Yellow, Huaihe and Songhuajiang. The simulation was assessed with 4 criteria. The study demonstrates that GR3 is satisfactory in long term continuous and event simulation and water balance, stable between the periods of simulation and validation, and has better performance in humid areas than semi-humid ones. It can be concluded that GR3 is applicable in China.