金沙江流域云南片水文极小值演变及生态基流保障分析

基于金沙江流域云南片内主要支流1968—2017年水文径流极小值及年月平均流量数据,采用一元线性回归、Mann-Kendall等分析其极小值演变特征,采用Tennant法及地区经验综合分析其河道生态基流,并对其生态基流保障程度进行了评价。结果表明:东北区、西北区为年极小值对应每100 km~2产流高值区,滇中区为低值区,地区差异显著,东北区年径流极小值呈现显著波动减少趋势,滇中区、中北区及西北区变化趋势不一;主要支流平均仅有47%的年份生态基流得到全部保障,53%年份水文极小值低于生态基流,其中东北区及西北区保障程度较高,滇中区保障程度低;预计东北区受天然来水影响、西北区部分河流受水利水电工程调度影响,生态基流保障压力将逐步加大,滇中区除昆明、曲靖部分河流生态基流保障程度将逐步得到改善外,其他大部分河流将持续处于高压状态。     

河道生态基流保障引起的农业损失量计算

为了科学协调水资源短缺地区农业用水与生态基流的矛盾问题,推动生态基流保障工作开展,从优先保障生态基流后农业受到影响的角度出发,确定了不同保障水平下的农业损失量。以渭河干流宝鸡段为例,定量计算了生态基流调控值在5～10 m~3/s之间时宝鸡峡灌区的农业产值损失与产量损失,并分析了生态基流保障前后保障率变化情况。结果表明:生态基流调控值在5～10 m~3/s之间时,平水年农业产值损失在1. 04×10~8～2. 54×10~8元之间,枯水年农业产值损失在2. 99×10~8～4. 06×10~8元之间,特枯年农业产值损失在4. 78×10~8～6. 61×10~8元之间。减少农业灌溉引水后,河道生态基流保障率明显提高。     

河道生态基流生态经济价值及其时间变化研究

为了解决普遍采用单方水资源价值计算河道生态基流价值的缺陷,以及探索河道生态基流价值定量化计算新方法,采用水力学方法将河道生态基流从径流量中分离出来,并确定河道生态基流对应水面面积,进而采用当量因子法计算河道生态基流价值和并探索分析了河道生态基流价值的时间变化特征。以渭河干流宝鸡段为例进行研究,结果表明:渭河干流宝鸡段的丰水年、平水年以及枯水年的年平均河道生态基流量分别为5.82 m~3/s、3.59 m~3/s和2.76 m~3/s。近21 a来,该段河道生态基流价值在时间上总体呈下降趋势,该价值多年平均值为5.61亿元,单方河道生态基流价值为6.27元/m~3,单方价值与价值总量变化趋势相反。河道生态基流价值年内变化具有明显的周期性,总体呈倒"V"字型,汛期河道生态基流价值比非汛期大,单方河道生态基流价值与之相反。通过相同区域以及相近区域的河道生态基流价值研究成果以及价值变化特征的对比分析,证明研究成果较为合理。该方法可为河道生态基流合理保障提供定量化依据。     

长江中游典型河段底栖动物的物理栖息地模型构建与应用

考虑水生生物生境需求的物理栖息地模型被认为是评估河流流量变化对水生态系统影响的最可信的方法之一。本研究选取长江干流含有河漫滩的监利江段为实例,建立底栖动物各类群的物理栖息地模型,计算变化流量下栖息地适宜面积的时间序列,并据此进行生态流量决策。结果显示长江中游底栖动物最敏感的环境参数是流速,适宜范围为0～0.2 m/s;其次是水深,适宜范围为0～6 m。在考虑敏感环境参数的前提下,得出监利江段底栖动物的最佳生态流量为20 000 m3/s。三峡大坝蓄水后枯水期和平水期底栖动物适宜面积的低值部分减小,丰水期适宜面积增加。为了保护底栖动物栖息地,建议三峡大坝在防洪蓄水的同时能兼顾底栖动物的生态流量需求,调节枯水期和平水期的流量,让监利江段接近4000 m3/s,丰水期接近20 000 m3/s。在枯水年增大枯水期和平水期的流量,平水年增大枯水期的流量,丰水年减少丰水期的流量。本研究方法可以供长江其他河段目标物种的生态流量决策和生态修复方案设计参考。     

基于3E决策的崆峒水库优化调度

传统的水库调度以兴利和除害为主要目的,而基于3E决策的水库调度则实现了水库经济、社会和生态的多目标优化调度。首先采用逐月最小和频率计算方法计算最小生态流量和适宜生态流量,选定适宜于崆峒水库的生态流量;然后建立3E模型,采用二元比较模糊决策分析方法确定各个目标的不同权重,将多目标单一化;最后采用粒子群算法对模型进行求解。求解结果表明:使水库供水效益最大的供水量为4 622×10~4m~3,其中农业总供水量3 630×10~4m~3,工业和生活总供水量992×10~4m~3,而维持生态基流的生态用水量为2 311×10~4m~3。这可为水库的后期调度提供决策依据,也为水库的供水矛盾体提出了加强水利改革的建议。     

考虑水文改变生态指标的丹江口水库多目标优化调度

对水文改变指标进行分类、筛选并赋权,构建流量等级和流量波动 2 个生态指标;使用高斯径向基函数拟合 水库调度规则,以供水量、发电量和水文改变生态指标为目标函数,在丹江口水库开展多目标优化调度研究;分析 供水、发电与生态效益各指标间的竞争关系,寻求社会经济和生态效益均较佳的调度方案,论证生态流量的合理 性。结果表明：丹江口水库调度的供水、发电和生态效益之间存在目标冲突;同时考虑供水、发电、流量等级、流 量波动 4 个目标的推荐方案,可在确保防洪安全并维持供水和发电量不变的前提下,保证流量等级和流量波动水 文改变生态指标与天然状态相近;推荐方案尽可能达到适宜生态流量,满足了汉江中下游水生物自然繁衍需求。 研究成果可为丹江口水库优化调度以及汉江中下游水生态环境保护提供参考。     

基于开源和节流的乌伦古河流域水库群生态调度

针对乌伦古河流域水资源短缺、灌溉挤占生态用水等问题,以生活、工业、灌溉、河道生态基流、河谷林草及补湖生态用水为调度目标,设置开源、节流方案集,建立了以生态缺水量和社会经济缺水量最小为目标的水库群生态调度模型,采用人机对话模拟优化算法求解模型。结果表明：各节流方案的河谷林草和补湖供水保证率能够满足设计要求,缓解了灌溉用水与生态用水间的矛盾,但2017现状水平年和2025远景水平年需水方案的灌溉保证率未满足设计要求;当开源+节流方案调水量超过1.0亿m³时,满足农业灌溉、河谷林草和补湖的供水保证率要求,消除了灌溉用水与生态用水间的矛盾;随着调水量超过1.0亿m³且持续增加,对河谷林草、补湖缺水量、破坏深度等影响不大,推荐1.0亿m³为最佳调水量。     

Comparison of potential water supply and demand in Taiwan

The authors estimated the potential water supply in Taiwan based on hydrologic and water resource data sets pertaining to 233 rainfall stations, 145 stage stations and 109 reservoirs. The comparison between potential water supply estimates and predicted water demand indicated a slight water shortage, even though Taiwan normally receives a large amount of rainfall. This predicted water shortage likely occurred due to the uneven distribution of rainfall in Taiwan. Taken together, the results of this study demonstrate the importance of conservation of forests and paddy fields for the maintenance of base flow and effective management of reservoirs in Taiwan.     

基于黄河鲤栖息地水文-生态响应关系的黄河下游生态流量研究

本研究采用野外生物监测、栖息地同步观测和实验室控制实验等技术手段,应用生物学、鱼类生态学、生态水力学、水文学等多学科理论,基于河流栖息地模拟法,研究了黄河下游指示物种黄河鲤生态学特性及其栖息生境与流速、水深、水温等水文水环境因子之间的关系,将径流条件与目标物种不同生长阶段生物学信息相结合,建立了代表物种繁殖期、越冬期栖息地适宜度指数,构建了黄河下游重点河段河流栖息地模型,建立了指示物种栖息地状况与河川径流条件定量响应关系,提出黄河下游花园口和利津断面繁殖期最小生态流量为300 m³/s和100 m³/s、适宜生态流量为600~700 m³/s和190~250 m³/s。该研究在水生生物习性及其与河川径流响应关系方面实现突破,解决了黄河生态需水研究中关键技术问题。     

于桥水库流域水源供给服务的空间分布格局

空间定量评估流域生态系统水源供给服务功能对水源区可持续发展及生态补偿机制的建立具有重要意义。基于研究区土地利用数据、气象数据和土壤数据,应用In VEST模型评估了于桥水库流域生态系统的水源供给量,并定量分析了流域水源供给能力的空间分布格局特征。结果表明:当Zhang系数为3.2时,流域的年径流深为161 mm,流域内年总产水量为3.14亿m~3。从空间分布格局来看,流域水源供给量存在显著的空间异质性;南部和中东部平原区单位面积水源供给量较高,水库南岸水源供给能力高于北岸;遵化市和蓟县对水源供给总量的贡献率达到85%;流域内不同景观类型的水源供给能力由大到小的排序为:耕地林地人工表面裸地灌草地,耕地、林地和人造表面对水源供给总量的贡献率达到82%。流域南部和中东部平原区是水源供给功能保护的重点区域,但同时也是防控城镇面源污染的关键地区。     

汉江桥闸工程下游河段典型鱼种栖息地模拟研究

探究水利工程干扰下的鱼类生境变化特征是维护河流生态健康的基础性研究。以汉中平川段内汉江三桥桥闸下游10 km为研究河段,利用水文学法和栖息地模拟法计算了生态流量。建立了河段二维水动力学模型,选用宽鳍鱲为目标鱼种,依据其对水深和流速的适宜性曲线确定了流量变化下的生境面积,并采用生境质量分级分析了不同流量响应鱼类生境的变化特征。研究结果表明:两种方法计算出河流生态流量相近,分别为54.3和53.1m~3/s,最终适宜流量为47.8～54.3 m~3/s;在流量8.8～212.7 m~3/s时,相比中等和低质量生境,高质量生境面积随流量的波动更为显著,呈现先升后降的趋势,212.7 m~3/s以上流量的各级生境面积随流量变化较小;高质量生境多分布于两岸和冷水河交汇口,中等质量生境主要分布在河段下游;低质量生境位置相对不固定;研究成果可为桥闸运行和河流鱼类保护提供重要参考依据。     

基于径流还原的桑干河生态基流及其盈缺分析研究

考虑到流域内水循环及降雨径流关系,通过对径流还原后,采用生态基流计算方法,确定桑干河生态基流量,进行桑干河生态基流分析。针对桑干河罗庄-固定桥、固定桥-册田水库逐年计算时,采取逐项还原法,逐项还原断面以上未实测到的水量,加上断面实测径流,还原为断面天然径流量。采用Tennant法计算桑干河生态基流量,并与最小月平均流量法的计算结果进行对比。Tennant法生态基流量多年平均计算值介于25%和50%频率年的计算结果,符合实际情况。通过对桑干河灌区引水与河道实测径流变化对比,发现其引水对河道生态基流起到了制约作用,需要采取措施来解决生态基流的缺水问题。     

渭河关中段生态基流保障对灌区的影响及补偿研究

针对枯水期河道生态基流保障造成的农业灌溉用水短缺问题,研究其对灌区的影响及生态补偿量,以推动基流保障工作的持续开展和日益完善。定性分析灌溉用水短缺可能产生的影响,明确不同方案引起的灌区灌溉缺水量,并应用水分生产函数模型估算造成的农作物减产损失,进而确定对灌区的生态补偿量。以渭河关中段为例,对3种基流保障方案造成的灌区灌溉用水短缺问题进行分析计算。结果表明:3种基流保障方案对宝鸡峡塬上、塬下灌区及交口抽渭灌区冬小麦的生态总补偿量分别为2800.30×10~4元、32392.58×10~4元、98817.98×10~4元。     

Ecological impact assessment of dam construction: A case study of Diamer Basha Dam Gilgit-Baltistan,Pakistan

Dam construction poses significant ecological impact, both during the initial construction phase and long after the dam is completed. The Diamer Basha Dam, situated on the River Indus in the Gilgit-Baltistan district of Pakistan, is receiving significant attention due to the ecological consequences of the proposed and ongoing construction. The Dam is a 272-m-tall reservoir with a 9867.912 Mm³ (million cubic meter) capacity and will be the world's highest roller compact concrete dam. The assessment of local ecological impacts was compiled in a checklist and matrices format to discuss the impacts on the status of species diversity in the study area. Using a random sample methodology, line transects, and quadrats were employed to evaluate phytosociological properties of vegetation. The floral parameters recorded were percent cover, species richness, vegetation composition, frequency, and density. The ecological analysis included principal component analysis to compare the distributions of sustained and lost vegetation in response to water flow variables. This research showed that several plant species withstand periods of high peak flow, like Salix tetrasperma, Rumex dentatis, Trifolium resupinatum, and Polygonum. Additionally, visual observations, plot surveys, transects, and published reports were used to compile the faunal data used to determine habitat distribution. According to the analysis, immediate effects of dam construction activities such as blasting, quarrying, and traffic noise cause severe disturbances to existing biodiversity and habitats with high ecological vulnerability, and have long-term effects on ecological integrity and environmental health in downstream and upstream habitats. The study presents the present status of biological and ecological conditions, as a baseline reference datum for a comparative analysis of the changes caused by the dam's construction.     

基于栖息地模型的新安江坝下生态流量研究

通过水力学模型与物理栖息地模型的耦合建立,揭示水文水力学与河流生物生命过程的响应关系,探索水生生物最佳生境所需的生态流量,为构建系统理论提供依据。基于物理栖息地模型,运用MIKE 21二维水力学模型模拟新安江坝下江段不同流量条件下的水深、流量分布,利用PHABSIM栖息地模型作出流量-WUA关系曲线,并得出虹鳟鱼适宜生态流量为160 m3/s,该值介于tennant评价标准极好与最佳之间,分析认为该计算结果更为合理,可为虹鳟鱼的保护和新安江水库的生态调度提供参考。     

Estimating the Ungauged Natural Flow Regimes for Environmental Flow Management

Regime-based approach recently becomes an important strategy while considering aquatic ecosystems in environmental flow management. The key element for supporting this strategy is long streamflow data which is usually not available for determining natural flow regimes. This study uses a back-propagation network to estimate ungauged natural flow regimes. A set of the upper reaches of Taiwan’s 42 flow stations with non-human control streamflow and at least 20 years daily flow data is used to quantify the natural flow regimes using 31 Indicators of Hydrologic Alteration (IHA). Watershed geomorphologic characteristic factors and rainfall parameters are used to classify homogeneous flow regime areas. The results show that there are three types of flow regimes from the flow stations, and each group of indicators in the IHA has different correlations with different geomorphologic characteristic factors and rainfall parameters. The results of using an artificial neural network model to estimate IHA show that the group average percent error fell from 21 % to 8 % and the average correlation coefficient was over 0.7, indicating that the model presented in this study is able to accurately estimate the natural flow regime in ungauged stations. Instead of predicting daily streamflow, this study estimates indicator values for ease of ecological water resources management.     

基于生态水文阈值调控的内陆干旱区水资源多维均衡配置研究

针对内陆干旱区城市发展和生态环境保护的强烈互斥性,在整体识别内陆干旱区水循环与生态演变耦合作用机理上,构建基于生态水文阈值调控的水资源多维均衡配置模型。模型分3个层次:以流域为单元的水资源系统耗水总量和地下水采补平衡;以行政分区为单元的经济社会系统水量平衡和水土平衡;以河道关键控制断面和灌区为单元的生态环境系统水生态平衡和水盐平衡,并给出相应的多重循环迭代算法。将该模型方法应用于我国内陆干旱区——塔里木河流域,结果显示:在平枯水平年通过累计新增节水灌溉面积85.1万hm~2,累计退减基本农田外灌溉面积41.5万hm~2,累计退减国民经济用水量为75亿m~3,可实现该地区水资源-经济社会-生态环境复合系统的有序良性演化和高效均衡发展,验证了该方法的可行性。     

淮河流域环境流变化及其对洪泽湖鱼类栖息地的生态影响

为分析淮河流域环境流要素的变化趋势及其对洪泽湖鱼类栖息地的生态影响,以淮河中下游河段为研究区,采用IHA法,将蚌埠水文站1950—2015年径流序列划分为2002年蚌埠闸扩建前后两个时期,采用5种流量事件筛选出32种环境流评价指标,分析了水文变异条件下5种环境事件的生态效应;以鳜鱼为洪泽湖指示鱼类,综合考虑栖息地限制因子,运用PHABSIM模型得到栖息地加权可利用面积-流量曲线,计算了鳜鱼产卵期的生态流量。结果表明:淮河中下游环境流组成趋于单一化,大洪水事件减少,枯水流量增大,高脉冲流量持续时间缩短,出现次数增加,对下游生态环境不利;洪泽湖鳜鱼4—6月产卵期的最小生态流量为300 m~3/s,适宜生态流量为550 m~3/s;需合理调控环境流,增加鱼类补充和物质循环,并采取湖泊生态修复等措施,维持洪泽湖的生态平衡。     

基于干旱河道生态修复的岳城水库生态调度

根据干旱风沙河道生态修复目标,结合水库的防洪、兴利、生态调度,建立了多目标水库生态调度模型,研究漳河岳城水库的生态调度。结果表明:枯水年岳城水库向下游河道生态供水0.277×10~8m~3,平水年岳城水库向下游河道生态供水0.327×10~8m~3,丰水年可以满足下游生态需水量2.66×10~8m~3。     

An Optimal Reservoir Operation Model Based on Ecological Requirement and Its Effect on Electricity Generation

Rather than optimizing water regimes for one or a few species, a better approach is to approximate the natural flow regime that maintains the entire panoply of species. RVA method generally describes flow regimes through 32 hydrologic indicators, quantifies the changes of the indicators post-dam, and distinguishes the highly changed indicators. Based on this function, an ecological objective which takes natural flow regimes into consideration is established. The objective synthesize highly changed indicators selected from the 32 hydrologic indicators and minimize their degree of change to approximate the natural status. The function of the hydrologic indicators are quantified through fuzziology according to their effect on river environment when changed. The model is applied to Xiangyang section of the Han River downstream the Danjiangkou reservoir, which maximizes the ecological objective to close to a natural flow regime. By optimization, model results indicate that the maximum synthetical membership of the selected indicators is 0.5, which means that the post-regulation optimum release is 50?% closer to the natural flow regime. It is much better than the traditional power generation regulation model, the membership of which is only 0.2. The result indicates that the ecological model is better in improving the river ecosystem, but with reduced power generation because of excessive abandon water. However, when deeply evaluate the effect of the new model, it shows the possibility of a win-win scenario between maintaining ecosystem health and power generation.