The hyporheic zone functions as a critical interface mediating hydrological and biogeochemical exchanges between stream water and streambed. Within shallow streambed layers, sediment transport and biofilm colonization can induce dynamic layered clogging, alter hydraulic conductivity, and foster physical stratification that significantly modulates hyporheic exchange patterns. This study develops a coupled hydrodynamic–mass transport model for a representative streambed bedform to examine the impacts of biofilm-driven dynamic clogging on hyporheic exchange dynamics. Results reveal that dynamic layered clogging reduces pore water velocity and total water flux, causing a 45.1% decline in the total inflow to the hyporheic zone. The transport of non-absorbable solutes exhibits a biphasic pattern: initial rapid penetration transitions to gradual deceleration over time, with dynamic clogging extending the penetration time of the solute center of mass distribution (CMD). Notably, when hydraulic conductivity falls below a threshold (K* < 0.25), CMD penetration time exhibits a positive correlation with hydraulic conductivity, attributed to porosity-induced changes in actual flow velocity. When considering the anaerobic growth in deeper layers, the penetration time become longer because of the clogging present there. This research clarifies the mechanistic connections between biofilm-induced clogging and hyporheic exchange, providing valuable insights for the management of hyporheic ecosystems and the modeling of biogeochemical processes.

受三级航道整治工程、区域下垫面条件和极端气候等变化环境影响,苏南运河成为太湖流域"涨水快、退水慢、水位高"的高水河道和防洪排涝突出薄弱处.基于实测水文资料,结合水动力模型手段,对2016年流域特大洪水发生时期苏南运河实况洪水过程开展分析模拟,结果表明,在各项治理措施实施后,可以分段解决运河洪涝水出路,降低运河沿线洪水位.研究发现,在苏南运河上游湖西区段,河道汇流以北排长江和沿运河下泄为主,武澄锡虞区、阳澄淀泖区段水流去向受长江和太湖两侧洪(潮)水位影响,当外部长江水位较高时,通过运河调蓄缓排是主要洪水出路.结合区域治理情况,按照"扩大外排、增加调蓄、控制下泄"的分段治理理念提出相应对策措施.

Study region: The Taihu Lake is located at the downstream of the Yangtze River, China, which serves various functions such as regional flood control, drought resistance, and drinking water for many vital cities in China such as Shanghai, Hangzhou and Suzhou. Since 1950 s, Taihu Lake has experienced three stages of anthropogenic management. Due to these managements, the natural hydrologic properties of Taihu Lake are gradually disappearing, and the Taihu Lake tends to become an artificially controlled lake. Study focus: To understand how anthropogenic activities have impacted the hydrological regime of Taihu Lake at different stages, this study has analyzed daily average water level of Taihu Lake for 70 years and daily average precipitation data of the Taihu Lake Basin for 60 years. And finally it reveals the natural and anthropogenic effects on trend, amplitude, period and extreme water level of Taihu Lake. New hydrological insights for the region: The multi-year average water level of Taihu Lake witnesses an increment of 0.23 m, and the contribution from anthropogenic activities account for 34.78%. The maximum decrements of frequency of extreme high and low water level drops by 29.55% and 7.69% recently due to anthropogenic activities. The anthropogenic activities on the hydrological regime in Taihu Lake has become increasingly pronounced, and these hydrological changes are beneficial for basin flood control and water resources.

城市水网不仅关系防洪、水资源和生态环境安全,同时也是生物多样性的生命之桥.文章以维护河湖健康生命、实现河湖功能永续利用为目标,剖析城市水网特征,以系统治理、协同治理的总体思路,统筹水网多 目标需求,构建城市生态水网建设指标五大体系.在河湖生态保护视角下,探讨城市水网建设策略,着力打造河畅水清、岸绿景美、人水和谐的美丽河湖.

针对无资料地区的洪水预报和设计洪水计算常受到降雨流量等资料制约的问题,以洛阳河流域无资料地区为例,通过DEM数据提取洛阳河流域霍顿地貌参数,计算洛阳河流域地貌单位线,从而建立起流域汇流与地貌参数之间的响应关系,并采用三层蒸散发和蓄满产流模型,构建基于地貌单位线汇流的新安江模型,同时结合遗传算法和客观优选法思路对洛阳河流域洪水进行模拟演算,并与传统的新安江模型结果进行对比分析.结果表明,基于地貌单位线汇流的新安江模型能取得较理想的模拟结果,可为中小河流无资料地区的水文分析计算提供可靠的技术支撑.

基于长荡湖不同位置的风浪实测资料,对实施水利优化工程后的长荡湖风浪特征进行了分析.结果表明,风速较大时,湖心水域总体风浪强度较大,长荡湖谱峰周期与平均波周期和跨零周期都存在显著线性相关.生态潜堤可以有效削减西湖近岸水域风浪强度,有效波高衰减百分比介于56％～81％,平均周期衰减百分比介于14％～31％.西部近岸水域风浪强度的削减,有利于水体透明度增加,从而为近岸水域水生植被的修复提供较好的生境条件.

基于1986—2018年期间环太湖水文巡测资料,分析了环太湖及主要水资源分区出入湖水量的时空变化趋势.研究结果表明,环太湖入湖水量历年变化整体呈增加趋势,在2007年前、后2个时期年均入湖水量增加了29.9亿m3.太湖入湖水量增加主要集中在湖西区,浙西区入湖水量变化则相对稳定,但在年内水资源调度期时浙西区入湖水量表现出减少的趋势.受太湖水位上涨影响,环太湖出湖水量也表现出增加的趋势,这主要反映在流域下游的阳澄淀泖区和杭嘉湖区出湖水量的增加.此外,受供水调度影响,太浦河出湖水量也表现出增加的趋势,特别是在金泽水源地投入使用以后,水资源调度期太浦闸日均下泄流量增幅明显.

深入认识大型湖泊在不同风速、风向和水位下三维风生流结构特征对于湖泊污染控制、生态恢复及资源的开发利用具有重要意义.本文在构建笛卡尔坐标系下洪泽湖三维水动力模型的基础上,利用2次全湖30个点位流场监测数据验证了模型精度.基于1975 2020年长系列风场观测数据,确定了洪泽湖典型风速风向.在此基础上,模拟了16种不同风向,13种不同风速和20种不同水位工况条件下洪泽湖三维风生流结构.结果表明:水动力模型可以较好地刻画洪泽湖三维湖流变化特征.洪泽湖风生流结构随风向变化呈现出较大空间差异.风生流流速随着风速的升高呈加速上升趋势,其中表层水体流速上升幅度远高于其他水层.在2.4 m/s东风驱动下,溧河洼、成子湖和南部湖区垂向平均流速随着水位上升呈先升高后降低的趋势,3个湖区分别在12.7、12.4和12.2 m水位下流速达到最大值.

为了提高通胜山丘区来水模拟精度,解决通胜地区防洪安全问题,分析了洛阳河流域下垫面土地利用类型,并基于遗传算法构建水文模型进行洪水模拟.结果 表明,近20年来,在现有气候、下垫面等变化环境下,洛阳河流域下垫面不同土地类型面积变化较大,快速城镇化使得旱地明显减少,水田增加11％,水面基本保持不变,水文模型参数也在发生动态变化,新水文参数与原始水文参数相差较大,前者模拟结果在径流深、洪峰、峰现时间、确定性系数4个方面均明显优于后者,可见基于遗传算法优化的水文模型参数能较好地反映现状下垫面水文情景.

针对湖西通胜地区整体防洪标准偏低及骨干河道行洪能力不足等问题,建立基于MIKE11模型的通胜地区水利计算模型,评估地区现状防洪排涝能力.围绕通胜防洪设计水位目标,依托流域与区域防洪体系,遵循“上蓄、中滞、下泄”的治理原则,分析研究通胜地区河道整治方案,提出符合通胜地区实际和需求的可持续治理对策,进一步完善通胜地区防洪除涝格局,全面提高通胜地区防洪标准,为地区安全提供有效保障.研究表明:通胜地区现状防洪标准总体不足20年一遇;通过实施通济河、胜利河及简渎河整治工程措施,可有效实现丘陵山区洪水安全有序下泄,满足通胜地区防洪设计水位目标.

随着江南运河沿线城市的快速发展,江南运河由以航运为主要功能转变为具有航运、防洪和排涝等综合功能的河道.2015～2017年,江南运河洪水位屡创历史新高,沿线多处出现险情,逐渐成为了流域防洪的薄弱环节.在对江南运河及流域的综合治理工作开展大量研究的基础上,梳理了江南运河的历史变迁及其与沿线城市发展的关系,总结了江南运河的治理现状.在此基础上,利用所掌握的水文数据,对近年来江南运河洪水的运动规律进行了统计分析,根据统计结果,从经济社会发展、下垫面变化、洪水出路、流域防洪和区域排涝矛盾等方面,对运河的现状防洪形势及其存在的主要问题开展了分析研究,并提出了相应的对策措施,以期为江南运河下一步治理提供技术参考与理论支撑.

选取太湖流域湖西山丘区具有代表性的洛阳河流域,收集了2016—2017年的实测洪水资料,采用API水文模型、新安江模型和太湖流域水文模型进行洪水模拟,分析各模型的适用性和模拟精度.研究表明,各模型在洛阳河流域的适用性较好,均取得了良好的效果,其中新安江模型模拟精度总体优于API模型和太湖流域水文模型,为湖西山丘区其他小流域的洪水模拟提供了参考.

To clarify the spatial distribution and pollution status of nutrients in the surface sediments from a macrophyte-dominated zone in Lake Taihu, total nitrogen (TN), total phosphorus (TP), alkali nitrogen (AN), available phosphorus (AP), and organic matter (OM) were measured at 60 sampling sites in Xukou Bay. A pollution evaluation and source apportionment analysis of these nutrients was also carried out. The average contents of TN, TP, AN, AP, and OM in the surface sediments of Xukou Bay were 1027.5, 423.2, 46.4, 15.3, and 17096.6 mg·kg-1, respectively, with the OM content being significantly higher in the northeast zone than in other areas of the bay. The average value of STN and STP was 1.75 and 0.91, respectively, indicating that TN and TP represent moderate and mild levels of pollution, respectively. The average comprehensive pollution index (FF) was 1.57, indicated that the surface sediment was moderately polluted. The observed organic pollution index indicated that the surface sediments in Xukou Bay were generally clean. Based on C/N values, organic matter in the surface sediments is derived from the bio-deposition of non-fibrous plants and phytoplankton. Based on correlation analysis, OM and TN in the surface sediments of Xukou Bay are derived from the same source, while TP is derived from an alternative source.

The concentrations and spatial distributions of eight heavy metals in surface sediments and sediment core samples from a shallow lake in China were investigated to evaluate the extent of the contamination and potential ecological risks. The results showed that the heavy metal concentrations were higher in the northern and southwestern lake zones than those in the other lake zones, with lower levels of As, Hg, Zn, Cu, Pb, Cr, and Ni primarily observed in the central and eastern lake regions and Cd primarily confined to areas surrounding the lake. The concentrations of the eight heavy metals in the sediment profiles tended to decrease with increasing sediment depth. The contents of Ni, Cu, Zn, Pb, and Cd in the surface sediment were approximately 1.23-18.41-fold higher than their background values (BVs), whereas the contents of Cr, As, and Hg were nearly identical to their BVs. The calculated pollution load index (PLI) suggested that the surface sediments of this lake were heavily polluted by these heavy metals and indicated that Cd was a predominant contamination factor. The comprehensive potential ecological risk index (PERI) in the surface sediments ranged from 99.2 to 2882.1, with an average of 606.1. Cd contributed 78.7 % to the PERI, and Hg contributed 8.4 %. Multivariate statistical analyses revealed that the surface sediment pollution with heavy metals mainly originated from industrial wastewater discharged by rivers located in the western and northwestern portion of the lake.

By determining the nutrient and water contents in surface sediment in different region of Changdang Lake, combined with statistical analysis method, the spatial distribution and pollution characteristics were discussed.The results showed that the concentration of nutrient ranged from 3.47 to 10.80 g/kg for TN, from 0.57 to 1.83 g/kg for TP, from 0.66% to 4.21% for TOC, from 41.71% to 75.78% for water, with an average of 6.86 g/kg, 1.19 g/kg, 1.73% and 60.48%, respectively, which all had spatial distribution of high content in surrounding and low in central in the lake.A significant linear correlation was observed among total nitrogen, total phosphorus and water content, while there was not significant correlation among total organic carbon and total nitrogen, total phosphorus and water content.The enrichment coefficients varied from 0.7 to 2.0 for total nitrogen, from 0.6 to 2.0 for total phosphorus and from 0.4 to 2.5 for total organic carbon, with an average of 1.3, 1.3, 1.0, respectively.And that pollution index varied from 6.3 to 19.6 for total nitrogen, from 1.0 to 3.1 for total phosphorus and from 0.7 to 4.2 for total organic carbon, with the average of 12.5, 2.0 and 1.7, respectively, indicating that nitrogen level was in heavily polluted state and Changdang Lake was under a certain level of pollution of phosphorus, organic carbon in the surface sediment.

在分析河道的生态功能与目前生态河道建设所存在的问题的基础上,提出了生态河道建设的原则,并结合苏南某农村地区河道的现状,分析了该地区河道在生态建设方面所存在的问题,针对这些问题,从截污治污、底泥疏浚、活水工程、深化处理以及护岸工程5个方面规划了生态河道建设所采用的工程措施,为农村相似地区的生态河道规划与建设提供参考及借鉴.

分析了中国水利现代化发展需求,阐述了水利现代化的内涵与特征,评价了水利现代化现状水平,探讨了中国水利现代化基本目标、发展思路及未来发展方向和策略,以江苏省苏州市为例,介绍了苏州市水利现代化水平评估体系和现代化建设体系。

本文分析了苏州水利发展现状与面临形势,阐述了苏州水利现代化的基本内涵与具体特征,评价了苏州水利现代化现状水平,明确了苏州水利现代化建设目标和主要任务,探索了苏州水利现代化的实现路径,为我国走出一条中国特色水利现代化道路积累经验、树立标杆和提供示范。

随着经济社会的快速发展和城市化进程的不断加速,城市排涝的影响和地位日益突出,解决好城市排涝问题是保障地区经济社会稳定发展的基石。本文根据太湖流域典型平原河网城市——无锡中心城区的防洪特点以及无锡市区目前的工情、水情,在大包围设计暴雨标准下,根据包围圈内各片区的排水能力,通过调洪演算,拟定大包围不同启用水位方案的比较,对相应大包围内河道最高控制水位作了进一步分析研究,并针对分析结果提出了对策建议,为城市建设拓展更宽的空间。

作为太湖上游的滆湖是太湖整治与优化的重中之重,本文以大量资料为基础,分析总结了近30年来滆湖水环境变化特点,旨在对滆湖水环境恶化及其原因有一个全面的认识。结果表明:滆湖水质恶化,综合水质类别由III类变为劣ⅴ类,藻类等浮游植物快速繁殖,水生高等植物和鱼类等物种多样性锐减,致使整个湖泊已退化为藻型湖泊,呈现为重度富营养化状态。这主要是因为工业点源污染物排放增加,滆湖上游及周边地区污染物排放量增加,湖泊人工养殖投饵量的增加,湖泊底泥释放量的增加等。