长江中游江湖生物通道恢复的关键生物学问题与框架构建——以武汉市涨渡湖群为例

围绕生物通道恢复面临的科学、技术问题进行方案设计与分析，搭建生物通道恢复技术框架，为推动长江中下游江湖生态保护和修复工作提供技术思路与借鉴参考。以涨渡湖群为研究试点，系统总结了该水域江湖洄游鱼类在“长江-湖泊”的迁徙、洄游规律，掌握鱼类入湖和出湖习性。围绕幼鱼入湖、成鱼入湖与出湖等不同生活史阶段的需求，结合河湖水位变化特征与影响、现有工程及调度措施的局限性，提出了“季节性灌江纳苗”“生态水网+过鱼设施”及调度运行等方案，从保障江湖洄游性鱼类生活史完成的角度搭建生物通道恢复框架。工程建设、综合调度和管理措施旨在解决江湖复合生态系统江湖阻隔问题，以达到洄游鱼类及生物多样性恢复、河湖水生生境修复的目标。

Biological Problem and Framework Construction of Biological Corridor Restoration for River-lake Connection in the Middle and Lower Yangtze River: a Case Study of Zhangdu Lake

The restoration of the biological corridor between the rivers and lakes is one of the direct measures to relieve the impact of river-lake blocking and human activities on the biodiversity. The construction of biological corridor is helpful for fish migration between rivers and lakes. In this study, Zhangdu?Lake?group in Wuhan City of Hubei Province was selected as research, we discussed the scientific and technological problem for the restoration?of?biological?corridors and developed a technical framework for the restoration of biological passage in Zhangdu Lake group. First, we summarized?the?movement and migration?patterns?of?the?river-lake?migratory?fishes?in?this?water?area,?and characterized the different biological requirements of larval fish and adult fish as well as the migration periods of key life stages for migratory fish species, bidirectional migration routes between rivers and affiliated lakes. Then, we proposed a systematical construction scheme for the restoration of biological corridors connecting the Zhangdu River and the Yangtze River. The optimized scheme includes filling water flow to rivers to satisfy the requirements of larval fish drifting from river to lake during the periods from June to August, constructing ecological-friendly water network and fish passage facilities in consider of bidirectional migration requirements and water fluctuations resulted from the operation and regulation of sluice stations. In conclusion, the proposed schemes in this study met the?needs?of?migrotary fish species to complete different?life?history?stages?such?as?fish fries?entering?the?lake,?adult?fish?entering?and?leaving?the?lake.?Meanwhile, engineering?construction,?comprehensive?scheduling?and?management?measures?solved?the?problem?of?river-lake?separation?in?the?river-lake?complex?ecosystem. The present study provided restoration framework of biological corridors for river-lake connection, from which ecological protection and restoration in the middle and lower Yangtze River is benefited.