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人类为实现经济与防灾的需求目标,在天然河道修建水库或对天然湖泊进行改造形成水库。从经济的角度看,水库的建设满足了人们对于灌溉、发电、供水、航运以及旅游等方面的需求;从防灾减灾方面看,水库通过拦蓄洪水削减洪峰,有效地防止或减轻了洪水对人类的侵害。但与此同时,水库的修建也给库区及库区下游带来了许多生态问题。随着生态价值理念的日益提升,人们开始更加重视对大坝生态的研究,以大坝生态修复与补偿为主要内容的生态调度理论成为研究热点。文章选取在西藏经济社会发展中具有举足轻重地位的拉萨河流域为研究对象,分析流域内直孔水电站水库建成后对拉萨河流域生态的影响,并对拉萨河流域生态调度提出建议。 相似文献
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水库生态调度研究的若干思考 总被引:1,自引:0,他引:1
传统的水库调度方式在保障防洪安全的基础上力求最大限度发挥河流水资源的经济效益,对库区及下游的生态环境考虑较少,在防洪兴利的同时危及了河流健康。改变传统的水库调度方式,将生态目标纳入到水库调度中来,开展以维护或改善河流健康为重要目标的水库生态调度是十分必要和迫切的。从水库修建运用的生态效应出发,在国内外相关研究的基础上系统分析了水库生态调度的概念、内涵及研究热点,并重点讨论基于生态水文模拟的水库生态调度方式及其研究中的一些关键技术问题,以期能够对水库生态调度研究提供参考。 相似文献
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人类活动尤其是大规模的水利工程建设,极大地影响了河道径流的一致性,因此考虑径流年际变异的河道生态径流研究具有重要意义。以洮河流域为例,采用Mann-Kendall突变检验法和滑动t检验法对洮河中游岷县站、下游李家村站1950—2016年逐月实测径流做突变检验,借助逐月次最小值法、逐月频率计算法计算了两站河道最小、适宜生态径流,分析了水文变异前后生态径流满足情况以及流域发展带来的可能影响。结果表明:岷县站和李家村站年径流存在显著水文变异,突变点分别出现在1989、1991年;逐月次最小值法得到的最小生态径流和逐月频率计算法得到的适宜生态径流均可保证河流生境处于"好"及以上的流量范围内;水文变异后,河流最小、适宜生态径流满足情况均变差,尤其是在鱼类产卵育幼期(4—8月);现状河流来水存在显著减少变化,未来人类活动强度和影响范围将进一步加大,应立足流域角度,统筹考虑河流生态用水与经济社会用水。研究成果可为流域未来更好地开展水资源开发与利用工作提供一定的参考。 相似文献
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采用逐月频率计算法,分别计算水库修建前后河道生态径流,并对其变化情况进行比较,确定水库调度是否符合河道生态径流的要求。根据襄阳站水文资料对丹江口水库的调度进行分析,结果表明:丹江口水库目前的调度方式对汉江流域生态系统的影响比较大,提出了减小丹江口水库调度对汉江生态系统影响的措施:为减少这种影响,应以建坝前的最大、最小和适宜生态径流过程为准,对现有的调度规程进行适当修改,使以后运行的最小生态径流不小于建坝前的最小生态径流,最大生态径流不大于建坝前的最大生态径流过程,减小水库对生态系统的影响。 相似文献
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水利工程建设在促进社会经济发展的同时也给河流生态系统带来了一些负面影响,为了减轻水利工程对水生态系统造成的不利影响,结合中国的实际情况本文建立了在考虑水库原有功能的基础上,兼顾河流生态需求的水库生态调度模型。计算了河流最小生态流量、适宜生态流量和生态洪水。本文将建立的生态调度模型应用于南水北调中线工程的水源区丹江口水库,采用逐步优化算法求解生态调度模型,分析计算生态目标的加入对水库原有功能的影响。研究通过水库调度满足河流适宜生态流量,尽量不低于最小生态流量的调度方式;探讨通过水库调度模拟“人造洪水”,为鱼类的繁殖和生长创造适宜的水力条件。计算结果表明,丰水年在满足生态流量的情况下,对水库原有功能影响不大,然而平水年和枯水年在考虑生态需求时,对水库原有功能将产生一定程度的影响。因此需要在生态环境和经济效益之间均衡利用水资源,通过水库的生态调度保持河流天然适宜的径流过程,维护河流生态系统健康及水资源的可持续利用。
关键字:水库生态调度;河流生态需水量;生态洪水 相似文献
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中国分区域生态需水研究 总被引:7,自引:1,他引:6
概略介绍了国家“十五”科技攻关重大课题“中国分区域生态用水标准研究”成果。从基础理论、应用技术、管理决策三个层面.研究提出一系列相互关联的关键技术,形成符合我国实际的生态需水理论与计算方法体系。提出了水循环生态效应理论。建立了区域生态需水类型划分的三大准则,为区域生态需水计算奠定理论基础。提出了多参数河流生态需水理论,建立了多参数全过程河道生态需水计算方法。提出了湿地生态水文结构理论,建立了湿地生态水文结构模型计算方法。以生态需水特征值建立生态用水分析机制,提出处理经济用水与生态用水关系的准则;以生态河流的标准为基础,建立河流生态调度管理机制。 相似文献
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面向河流生态完整性的黄河下游生态需水过程研究 总被引:1,自引:0,他引:1
提供适宜的生态流量对维护河流健康和支撑人类社会发展具有重要意义。尽管栖息地模拟法物理机制清晰、应用广泛,但对生物群落考虑不足、生命节律信号缺失等问题长期存在。以维护河流土著生物群落完整性为目标,本文将天然水文情势作为参照系统,结合栖息地模拟与水文参照系统特征值,建立了一种面向河流生态完整性的生态需水过程评估方法,兼顾指示物种生存繁衍和土著生物群落基本生存。黄河下游利津断面评估结果显示:利津断面年最小生态需水量119亿m3,适宜生态需水量130~137亿m3,涨水期需提供1~2次持续时间不低于7 d、流量不低于1220 m3/s的高流量脉冲。对比历史实测流量过程与本文生态需水成果,发现利津断面水量充足,但流量过程不满足生态需求。黄河需加强水库群调度,协调径流年际和年内分布,塑造适宜的生态流量过程,并适时塑造高流量脉冲。 相似文献
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陈昂 《水利水电科技进展》2019,39(2):1-6
为了应对水文、气候和生态系统变化背景下环境流量研究的新挑战,梳理了国内外环境流量研究成果,指出目前环境流量研究主要存在5个方面的不足,也是该研究目前的前沿问题与挑战:①全球环境变化与非稳定性;②生态水文过程的动态模拟,重点是水文情势静态评价向动态特征评价研究的转变;③生态水文关系的时空特性,重点是生态系统状态、过程变量和物种特征的耦合研究,环境流量的生态特征和时空尺度研究;④环境流量评估的关键指标;⑤环境流量预测的生态学延展。为解决这些问题,提出了人类世背景下环境流量研究的发展方向,认为未来环境流量研究应加强生态目标的动态适应性管理,加强局域到区域的生态学基础研究,完善基于过程的生态水文响应机理,强化环境流量分阶段实施的非水文指标耦合,加强适应性管理方式下的环境流量评估和实践,以保障适应性管理框架下的生态完整性。 相似文献
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D. A. Hughes 《河流研究与利用》2005,21(8):899-908
The paper reviews the generic characteristics of ephemeral rivers compared with seasonal and perennial systems in the context of southern Africa. The difficulties of estimating the natural characteristics of ephemeral systems are discussed as well as the difficulties of estimating the impacts of water resource management strategies. Many of the problems are associated with the potentially discontinuous occurrence of flow in both time and space and the fact that static pools, as well as flowing water, may be of ecological importance. The most obvious impact of water resource developments on ephemeral rivers may be a reduction in the number and size of flow events. However, delays in the onset of flow in seasonal rivers and changes in the duration, quantity and quality of in‐channel pool storage may be of equal importance. In a number of South African ephemeral channels the major impacts have been caused by the importation of water from elsewhere and a consequent reduction in streamflow variability. The paper suggests that there are a number of gaps in the understanding of the hydrology of ephemeral rivers, but perhaps more importantly, in the methods that are available to supply the type of information required by ecological specialists to be able to determine ecological water requirements under managed flow situations. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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河流生态流量是维持河流生态系统健康的重要条件。选取湘江(湘潭)作为控制性断面,采用生态流量年内展布法和IHA-RVA法计算河道最小和适宜生态流量,并以Tennant法进行合理性验证。结果表明:最小生态流量为639.6 m~3/s,占多年平均天然流量的32.2%;适宜生态流量为983.4 m~3/s,占多年平均天然流量的49.5%。该方法计算的生态流量结果能够满足河流生态目标的需求,与天然河流年内丰枯变化状态相吻合,计算结果较为合理。研究可为湘江湘潭的水资源管理以及生态系统的保护和恢复提供科学依据。 相似文献
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Considerable attention has been paid to the downstream effects of reservoirs on the ecology of rivers, streams and wetlands. However, most reservoirs were constructed well before ecological concerns became prominent. Little attention has been given to the question of what extent existing structures and management systems can accommodate changes. The paper discusses this matter and a range of associated issues. It is concluded that many problems can be rectified by structural means but that such rectification will be very expensive. While based primarily on Australian systems, the conclusions and examination are considered to be globally applicable. 相似文献
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South African water resources legislation requires that environmental flow requirements are included as part of water resource management. An operational management method is presented that relies upon simulating natural flow conditions based on inputs of near real‐time observations of rainfall and a set of operating rules. The operating rules define the reservoir releases and water use supply curtailments that ensure downstream environmental flow objectives will be met. The focus is on managing the variability of continuous low flows, while a suitable method for managing event‐based high flow releases remains elusive. The main limitation to the successful implementation of the low flow approach is the lack of legislated control over run‐of‐river water abstractions. While this limitation is expected to be overcome, as the provisions of new legislation are implemented, water managers may still lack the capacity to exercise the necessary controls over abstraction. There is no reason why the method could not be applied outside South Africa, given compatibility in the definition of environmental flow requirements. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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Water management agencies throughout Australia are attempting to find a balance between the water requirements of ecological and socio‐economic environments as part of a holistic approach to managing flow‐dependent river ecosystems. Environmental water provisions are under consideration for the Ord River in far northern Western Australia. This river has been regulated for irrigation and there are plans for substantial expansion. Like other semi‐arid and tropical rivers, however, the hydrology of the Ord River is highly variable and unpredictable, and therefore, proportionate water release strategies for the environment that are based on average monthly flows are unsuitable. Regulation continues to produce pronounced ecological changes throughout the river system as the impacts of flow regime are negated. There is a dichotomy in optimal flow regimes for the contrasting management aspirations of ecological restoration based on low seasonal flows, and the dilution flows required for the drainage of agricultural effluent. Whilst current agricultural land and water management practices continue, the two cannot coincide, and consequently, a decision should be made regarding which environmental water allocation holds the primary value. Such a decision would guide the appropriate dry season flow regime on the lower Ord River. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
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针对太湖流域目前面临的湖体水质持续改善压力增大、水生态系统脆弱等问题,2012—2013年对太湖流域87个点位丰、平、枯水期进行生态调查。结果表明:底栖生物53%的点位、浮游植物65%的点位和浮游动物35%的点位Shannon-Wiener指数评价等级为贫乏;其次是面源污染日益突出,面源对太湖的污染贡献中COD、NH3-N、TP、TN分别占到总量的53%、46%、68%和45%;再次是工程缺乏长效运行管理机制,出现"重工程建设、轻运行管理"的现象。提出治理措施:1建立水生态功能分区,恢复生态系统完整性;2加大面源及农村黑臭河道治理力度;3制定严格的污染物排放标准;4提高治理工程运行管理水平。 相似文献