城镇河网水系受自然条件和人为因素的干扰,内涝灾害频发,亟需开展区域水系排涝优化方案研究工作.文章以广东省佛山市九江镇水系为例,通过构建一维河网模型,采取新开河道、水系连通、人工湖、水闸、泵站、清淤拓宽等整治措施,控制九江镇内河涌水位在管控水位1.7 m以下,以保障九江镇的内涝水安全.文章旨在研究九江镇内水系排涝优化方案的可行性,为后续镇区水系整治、调整提供重要依据.

水库调控下的水文情势、河道环境与鱼类行为之间如何驱动响应,促进生态良性循环的反馈调节机制如何科学建立,现有水库生态调度方案如何优化调整,是近年来我国试验性生态调度工作中面临的一连串新问题,也是我国马上步入后水电时代水库可持续运行与适应性管理迫切需要考虑的问题.通过系统调研和梳理总结,综述了水库调度环境下的鱼类生态响应与生态调度方面的研究进展,认为适应性管理闭环的顶层设计、人工调度环境下的鱼类行为响应机理、刺激鱼类行为响应的水文过程反馈调节机制,以及生态调度实践初期面临的小样本问题,是当前研究的难点和下一步亟待攻克的科学问题.在此基础上,提出了从"驱动力—状态—响应"这一逻辑链条有机串联和系统研究"水文过程—河道环境—鱼类行为"之间复杂响应与互馈关系的设想,并对未来生态水文学、生态水力学和鱼类生态学等多学科的贯通发展,以及新一代计算机和信息技术在本领域的尝试应用进行了展望.

Reservoir ecological operation creates artificial hydrological and hydrodynamic conditions to meet the demand of fish during key life periods, which provides eco-environmental protection to alleviate the negative impact of hydropower development on ecosystems. However, based on practical ecological operation experience, the flow experiments were rough in terms of plan design, most of which were implemented over short time frames, and circumstances where downstream flow conditions existed were inconsistent with fish requirements during periods affected by different local reservoir operation conditions. This finding suggests that current ecological operations leave considerable space for strategy refinement. This study proposed a methodology for designing refined operation strategies incorporating more ecological demands into reservoir operation releases to create and improve suitable ecological conditions for the spawning of representative fish species. A joint water quantity operation model of cascade reservoirs and an under dam-river hydrodynamic model coupling the operation conditions of hydroelectric generators was built. The proposed methodology was applied to the Three Gorges Dam (TGD) and Gezhouba (GZB) Dam cascade reservoirs in China. The simulation results indicated that (1) in most cases, the target of continuous flow increase on an hourly scale could be simply accomplished via hourly joint water quantity operation of TGD-GZB cascade reservoirs. (2) Maintenance of the average Dajiang and Erjiang generator output during the spawning period of Chinese sturgeon at a high outflow of 15000 m3/s could more effectively expand the integrated suitable space of Chinese sturgeon. We aimed to provide suggestions and references suitable for cascade reservoirs in China and worldwide to develop and optimize ecological operation conditions in more refined and diverse ways.

全球主要河流已成为受梯级水库控制的人工调节系统.河流鱼类作为淡水生态系统的重要组成部分,在人类对河流水能资源开发利用的进程中,面临着种群退化、多样性丧失的巨大胁迫.水库生态调度是在鱼类关键生命期人为营造满足鱼类需求的水文水动力条件,减缓水库不利生态影响的一种生态环保措施.然而,在生态调度的实践过程中,受水库不同运行方式影响,下游水流条件在局部时段存在与鱼类需求相悖的情况,有进一步提升空间.本文选择了当前世界上规模最大的三峡水电站和其下游的葛洲坝水电站为案例,建立了梯级水库联合调度模型,模拟分析了梯级水库协同运行改善下游河道鱼类繁殖条件的可行性,并探讨了优化调整策略.结果 表明,目前三峡、葛洲坝梯级水库生态调度的运行方式,大多数情况下仅通过葛洲坝水库小时尺度的精细调度,就可实现下游四大家鱼产卵繁殖所需的小时尺度连续涨水目标,并可一定程度提升发电出力,达到生态与经济共赢的良好成效.研究结果表明葛洲坝水库有能力在生态调度的特定时期内充分运用反调节库容调节三峡日出库流量过程,可为梯级水库生态调度的优化实践提供积极参考.