气候变化对澜沧江下游梯级电站发电及生态调度的影响

近年来伴随气候变化地表径流呈极端化分布，为水电生态调度带来了挑战。为探究气候变化对电站发电和生态调度的影响、发电和生态目标间协调关系对气候变化的响应，以澜沧江下游梯级电站为例，结合多模式多情景未来径流预估结果及水库发电调度模型，针对发电及生态效益目标实施了单/多目标最优化。结果表明：在气候变化影响下，未来澜沧江径流总量将有所增加，水文变率将显著增强，河道生态所受影响也将增大；电站发电保证率及生态流量破坏率指标受不同调度方案的影响程度较气候变化影响更高，未来发电和生态效益的冲突依然存在；气候变化导致的水文变率增强可加剧发电与生态效益间的冲突，导致保持现有发电效益的同时增大对河道生态的影响。     

气候变化对澜湄流域气象水文干旱时空特性的影响

受全球气候变化影响,澜沧江-湄公河流域气象水文干旱发生了较大变化,预测未来流域干旱的时空变化与传播特征是应对气候变化、开展澜湄水资源合作的基础。利用SWAT模型通过气陆耦合方式模拟了澜沧江-湄公河流域历史（1960—2005年）和未来时期（2022—2050年,2051—2080年）的水文过程,采用标准化降水指数和标准化径流指数预估并分析了流域未来气象水文干旱时空变化趋势。结果表明:①澜沧江-湄公河流域未来降水呈增长趋势,气象干旱将有所缓解,但降水年内分配不均与流域蒸发的增加,将导致水文干旱更为严峻,干旱从气象到水文的传播过程加剧;②水文干旱具有明显的空间异质性,允景洪和清盛站的水文干旱最为严重,琅勃拉邦、穆达汉和巴色站次之,万象站最弱;③未来流域水文干旱事件发生频次略有减少,但其中重旱、特旱事件占比增加,极端干旱将趋多趋强,且空间变化更加显著。     

高寒山区河道径流的形成与水文调节机制研究进展

高寒山区河道径流的形成与水文调节机制是认识流域水资源形成与转化过程,以及预测气候变化下流域水文过程响应规律的基础. 通过分析国内外相关文献,从高寒山区河道径流的水分来源及其气候变化下的影响机制、高寒山区不同类型下垫面对河道径流的调节机制、高寒山区不同类型地下水对河道径流的调节机制三个方面综述其研究进展,总结问题与不足,发现气候变化是影响高寒山区河道径流形成过程的主导因素,探究水文输入、下垫面、地下水等次要影响因素与气候变化之间的响应规律是揭示高寒山区河道径流水文调节机制的关键科学问题,并提出未来研究的总体趋势和改进建议,为高寒山区河道径流形成机制及其对气候变化的响应规律研究提供参考依据.      

气候变化对天山伊犁河上游河川径流的影响

用水量平衡模型研究气候变化对天山降雪比较丰富的伊犁河上游山区河川径流的影响。研究表明，作为西北干旱区水资源主要形成区的山区，由于气温较低和降水丰富，未来气候变化对水资源量的影响将主要取决于降水量的变化，气温升高的影响相对较小。气候的变暖，一方面使径流的年内分配发生变化，月径流峰值减少，时间提前，春季径流增加，而其余季节径流减少，其中夏季减少最多；另一方面将使年径流量的变率增大，这对水资源的利用极淡     

雅砻江下游梯级水库生态友好型优化调度

根据雅砻江下游梯级水库水电站的布置和河道生态环境要求,分别设置了两个流量控制断面:锦屏二级电站引水闸址下减水河段、二滩电站坝址下游河段.针对这两个控制断面河道流量的要求,提出了25组生态流量控泄方案,建立了以梯级水电站群发电量最大为目标的长期优化调度模型,并采用动态规划法进行求解,获得各个方案下梯级水电站群多年平均发电量及水库调度出流过程.比较分析了减水河段生态流量及二滩水库泄流控制方案对发电量的影响,定义并计算了生态需水电能损失指标.对梯级水库调度出流过程进行了初步评价.结果表明:二滩水库出流维持天然径流模式,将限制水库调节能力和减少梯级电站发电效益.     

气候变化对陆地水文、水资源影响的研究与进展

阐述了水文、水资源受气候变化影响的分析方法及近期研究结果。研究证实,温室效应引起的气候变化,将明显改变径流与水质等水文状况及未来水资源的规划与管理。     

气候变化对大凌河流域径流影响研究

利用区域气候模型PRECIS RCM模拟结果分析了研究流域未来温室气体在A2排放模式下规划水平年气候变化情况。将PRECIS模型模拟降水、蒸散发数据输入水文降雨径流NAM模型中,分析未来气候变化对研究流域径流影响。分析结果表明,未来气候变化条件下,受降水、蒸发变化影响,大凌河流域径流量会显著增加。     

黄河枯水期河道径流损耗估算及误差来源分析

为实施黄河水量精细调度，建立符合实际的水量调度数学模型，需要通过水量平衡计算。提供不同区段的水流传播时间和河道径流损耗等水文资料。通过对河道径流损耗量的分析计算，探讨了在水量平衡计算中影响河道径流损耗量的误差源及其对计算结果的影响程度，并提出了对各项误差源的控制措施。     

天山南坡高冰川覆盖率的木扎提河流域水文过程对气候变化的响应

木扎提河是天山南坡冰川面积覆盖率最大（48.2%）的河流, 流域径流过程对气候变化极为敏感, 为了合理管理和规划水资源, 确保水资源的可持续利用, 亟需定量评估气候变化对该流域水文过程的影响。以VIC-CAS分布式水文模型为计算平台, 利用实测的径流和两次冰川编目间的冰川面积变化数据开展了模型的多目标参数化校正和验证, 有效提高了模拟结果的“真实性”, 然后通过数值模拟结果结合观测数据定量解析了流域径流的组成、 变化特征及对气候变化的响应机理。结果表明： 木扎提河总径流集中在暖季（5 - 9月）, 占全年总径流量的77.9%, 冰川径流、 融雪径流和降雨径流分别占总径流量的66.6%、 26.4%和7.0%。1971 - 2010年木扎提河流域气温和降水呈显著增加趋势, 由于降水的增加, 降雨和融雪径流均呈增加趋势, 但冰川径流呈现明显减少趋势, 导致总径流呈现下降趋势。在RCP4.5情景下, 未来该流域气温呈现明显升高趋势, 降水表现为微弱下降趋势; 气候变暖后, 更多降水以降雨形式发生, 未来降雨径流将明显增加, 降雪和融雪径流已于20世纪90年代达到峰值, 随后明显减少; 冰川面积将持续萎缩, 冰川径流于21世纪10年代达到拐点, 随后明显减少, 导致河道总径流量也将明显减少。     

一种基于DS理论的水库适应性调度规则

针对适应性管理研究领域中GCMs集合子情景的权重取值尚不统一问题,通过DS理论综合考虑了3种权重分配方式:等权重、考虑年径流统计特征参数值变化的权重和基于相对月径流变幅的权重。基于得到的综合权重,进一步提出了一种基于DS理论的水库适应性调度规则,以规避气候变化对水库调度造成的不利影响。该调度规则,以多情景多年的加权平均发电量最大化为水库优化调度的目标函数,采用模拟优化法提取规则参数。以锦西水库的研究案例可知:在不确定的气候变化环境下,与基于历史径流的调度规则和基于等权重分配的适应性调度规则相比,基于DS理论的水库适应性调度规则不仅能够获取更多的发电效益（多发电量:0.76亿kWh、0.61亿kWh）与发电可靠性（多增发电保证率:0.5%~11.17%、3.50%~9.34%）,还具有更高的水库决策稳健性。因此,基于DS理论的水库适应性调度规则是有助于水库管理者应对气候变化。     

气候变化对江河流量变化趋势影响研究进展

气候变化对基于自然稳定气候假定的流量变化趋势的检测和水资源评价方法提出了挑战。在流量变化趋势的检测中分离出气候变化的影响,不仅对水资源管理和水利工程设计有重要的应用价值,而且有助于了解气候变化以何种方式、在何时、何地、已经或尚未对水文循环产生影响,对改进气候模型的模拟与预测有重要的科学价值。 统计方法是检验流量变化趋势显著性的有效工具。直接用气候模型模拟和预测未来径流变化的可靠性取决于模型对当代降水模拟的可信度。多个气候模型集合分析有可能在一定程度上减少模型对降水、径流模拟的不确定性。近年发展起来的多个气候模型集合分析与统计显著性检验技术结合的方法,有可能模拟并预测出气候强迫导致大尺度径流空间分布的变化。随着气候模型尤其是陆—气耦合的区域气候模型对降水模拟的改进,可以预见径流变化的检测、归因和预测的趋同化模拟已为期不远。将温室气体外强迫导致的水文气候变化作为一个因子引入到水资源评价中,对于水资源管理经济与生态评估,以及未来的发展规划将是一件十分重要的变革。      

Impact of water demand on hydrological regime under climate and LULC change scenarios

The present study focuses on an assessment of the impact of future water demand on the hydrological regime under land use/land cover (LULC) and climate change scenarios. The impact has been quantified in terms of streamflow and groundwater recharge in the Gandherswari River basin, West Bengal, India. dynamic conversion of land use and its effects (Dyna-CLUE) and statistical downscaling model (SDSM) are used for quantifying the future LULC and climate change scenarios, respectively. Physical-based semi-distributed model Soil and Water Assessment Tool (SWAT) is used for estimating future streamflow and spatiotemporally distributed groundwater recharge. Model calibration and validation have been performed using discharge data (1990–2016). The impacts of LULC and climate change on hydrological variables are evaluated with three scenarios (for the years 2030, 2050 and 2080). Temperature Vegetation Dyrness Index (TVDI) and evapotranspiration (ET) are considered for estimation of water-deficit conditions in the river basin. Exceedance probability and recurrence interval representation are considered for uncertainty analysis. The results show increased discharge in case of monsoon season and decreased discharge in case of the non-monsoon season for the years 2030 and 2050. However, a reverse trend is obtained for the year 2080. The overall increase in groundwater recharge is visible for all the years. This analysis provides valuable information for the irrigation water management framework.     

Assessing the effects of climate change on the hydrological regime of the Limay River basin

The electricity generation capacity in the Limay River basin is approximately 26% of the total electrical power generation in Argentina. Assessing the potential effects of climate change on the hydrological regime of this basin is an important issue for water resources management. This study explores the presence of trends in streamflow series, evaluates climate sensitivity and studies the effects on the flow regime of predicted changes in precipitation in the basin. In order to identify and quantify changes in observed streamflow series, the Mann–Kendall test, with a modification for autocorrelated data, and an estimator of the magnitude of the trend are applied. In order to evaluate the sensitivity of streamflow to changes in climate, the concept of elasticity is used. Precipitation elasticity of streamflow is used to quantify the sensitivity of streamflow to changes in precipitation and is estimated using a power law model and a linear statistical model in two sub-basins, Aluminé and Nahuel Huapi. The effects on flow regime of the predicted changes in precipitation under different scenarios are studied. Climatic results for different scenarios of growth in greenhouse gases from some General Circulation Models are used as inputs into the proposed models. The analysis identifies decreasing trends in mean and minimum annual flows and in the low flow season. The estimates of the precipitation elasticity imply that changes in precipitation produce similar changes in streamflow and the climatic results for different scenarios show that the variations are moderate.     

Modeling and assessing land-use and hydrological processes to future land-use and climate change scenarios in watershed land-use planning

Effective information regarding environmental responses to future land-use and climate change scenarios provides useful support for decision making in land use planning, management and policies. This study developed an approach for modeling and examining the impacts of future land-use and climate change scenarios on streamflow, surface runoff and groundwater discharge using an empirical land-use change model, a watershed hydrological model based on various land use policies and climate change scenarios in an urbanizing watershed in Taiwan. The results of the study indicated that various demand and conversion policies had different levels of impact on hydrological components in all land-use scenarios in the study watershed. Climate changes were projected to have a greater impact in increasing surface runoff and reducing groundwater discharge than are land use changes. Additionally, the spatial distributions of land-use changes also influenced hydrological processes in both downstream and upstream areas, particularly in the downstream watershed. The impacts on hydrological components when considering both land use and climate changes exceeded those when only considering land use changes or climate changes, particularly on surface runoff and groundwater discharge. However, the proposed approach provided a useful source of information for assessing the responses of land use and hydrological processes to future land use and climate changes.     

气候自然变异在气候变化对水资源影响 评价中的贡献分析——Ⅱ.未来期应用分析

基于模型率定期(基准期)气候自然变异的模拟方法及气候自然变异引起的径流变化的可能情况分析,此部分研究未来期(2021~2051年,2061~2091年)气候变化下径流变化情况及气候自然变异的影响。基于CSIRO、NCAR、MPI三种气候模式及A1B、A2、B1三种排放方式共7种未来气候情景,应用和基准期相同的水文模型和研究流域,引入基准期模型率定出的参数,考虑气候自然变异的影响,对未来气候变化对水资源的影响进行分析。为消除气候模式本身的系统误差,采用δ差值方法得到各模式各排放情景下的未来气候情景。该项研究主要说明如何在气候变化的影响评价中将气候自然变异的贡献分离出来,从而实现更客观的气候变化的影响评价。研究结果表明,气候变异的影响在整个气候变化进程中的贡献随时间的推移将有所不同。未来2021~2051年期间,气候自然变异的影响相对较大;未来2061~2091年期间,由温室气体引起的气候变化的影响占主导。     

Assessing the impact of future climate change on groundwater recharge in Galicia-Costa, Spain

Climate change can impact the hydrological processes of a watershed and may result in problems with future water supply for large sections of the population. Results from the FP5 PRUDENCE project suggest significant changes in temperature and precipitation over Europe. In this study, the Soil and Water Assessment Tool (SWAT) model was used to assess the potential impacts of climate change on groundwater recharge in the hydrological district of Galicia-Costa, Spain. Climate projections from two general circulation models and eight different regional climate models were used for the assessment and two climate-change scenarios were evaluated. Calibration and validation of the model were performed using a daily time-step in four representative catchments in the district. The effects on modeled mean annual groundwater recharge are small, partly due to the greater stomatal efficiency of plants in response to increased CO₂ concentration. However, climate change strongly influences the temporal variability of modeled groundwater recharge. Recharge may concentrate in the winter season and dramatically decrease in the summer–autumn season. As a result, the dry-season duration may be increased on average by almost 30 % for the A2 emission scenario, exacerbating the current problems in water supply.     

Climate change impacts on water demand and availability using CMIP5 models in the Jaguaribe basin,semi-arid Brazil

The objective of this study was to analyze climate change impacts on irrigation water demand and availability in the Jaguaribe River basin, Brazil. For northeastern Brazil, five global circulation models were selected using a rainfall seasonal evaluation screening technique from the Intergovernmental Panel on Climate Change named Coupled Model Intercomparison Project Phase 5. The climate variables were generated for the base period of 1971–2000, as were projections for the 2025–2055 future time slice. Removal of maximum and minimum temperature and rainfall output bias was used to estimate reference evapotranspiration, irrigation water needs, and river flow using the rainfall—river flow hydrological model Soil Moisture Accounting Procedure for the baseline and future climate (Representative Concentration Pathways 4.5 and 8.5 scenarios). In addition, by applying improved irrigation efficiency, a scenario was evaluated in comparison with field observed performance. The water-deficit index was used as a water availability performance indicator. Future climate projections by all five models resulted in increases in future reference evapotranspiration (2.3–6.3%) and irrigation water needs (2.8–16.7%) for all scenarios. Regarding rainfall projections, both positive (4.8–12.5%) and negative (??2.3 to ??15.2%) signals were observed. Most models and scenarios project that annual river flow will decrease. Lower future water availability was detected by the less positive water-deficit index. Improved irrigation efficiency is a key measure for the adaptation to higher future levels of water demand, as climate change impacts could be compensated by gains in irrigation efficiency (water demand changes varying from ??1.7 to ??35.2%).     

生态水文科学研究的现状与展望

生态水文科学研究是区域生态系统研究和区域水文科学研究的交叉领域 ,其核心内容是揭示不同环境条件下植物与水的相互关系机理 ,探索各种植被的生态水文作用过程。近年来 ,生态与水文相互作用过程的数学模拟和专门模型研制日益成为重要的发展领域 ,同时 ,生态水文学的研究十分注重尺度效应 ,把在一定尺度上获得的水文与生态原理或模型向其它不同尺度转换已成为最具挑战性的问题。山地生态系统成为全球变化研究最为重要的研究场所 ,开展与全球变化相关的生态系统物质与能量循环、生态过程的梯度效应及其与水文过程的耦合关系、生态系统结构与功能及其变化等方面的研究 ,是生态水文学研究最具活力的方向 ,其中建立包含区域气候变化因素的多元生态过程动态模拟模型 ,并使该模型具有不同时空尺度、不同地貌和生态带的广泛适应性是目前广泛关注的热点问题。     

Future climate change impact evaluation on hydrologic processes in the Bharalu and Basistha basins using SWAT model

Urbanisation and climate change can have adverse effects on the streamflow and water balance components in river basins. This study focuses on the understanding of different hydrologic responses to climate change between urban and rural basins. The comprehensive semi-distributed hydrologic model, SWAT (Soil and Water Assessment Tool), is used to evaluate how the streamflow and water balance components vary under future climate change on Bharalu (urban basin) and Basistha (rural basin) River basins near the Brahmaputra River in India based on precipitation, temperature and geospatial data. Based on data collected in 1990–2012, it is found that 98.78% of the water yield generated for the urban Bharalu River basin is by surface runoff, comparing to 75% of that for the rural Basistha basin. Comparison of various hydrologic processes (e.g. precipitation, discharge, water yield, surface runoff, actual evapotranspiration and potential evapotranspiration) based on predicted climate change scenarios is evaluated. The urban Bharalu basin shows a decrease in streamflow, water yield, surface runoff, actual evapotranspiration in contrast to the rural Basistha basin, for the 2050s and 2090s decades. The average annual discharge will increase a maximum 1.43 and 2.20 m³/s from the base period for representative concentration pathways (RCPs) such as 2.6 and 8.5 pathways in Basistha River and it will decrease a maximum 0.67 and 0.46 m³/s for Bharalu River, respectively. This paper also discusses the influence of sensitive parameters on hydrologic processes, future issues and challenges in the rural and urban basins.