水电工程影响下黄河下游重要湿地生态水文过程演变及调控机制研究

Hydrological process is the principle drive to wetland ecosystem evolution. The hydropower projects not only change the hydrological processes of rivers, but also significantly impact on the structure and function of wetland ecosystem. Dynamic response relationship between the hydropower projects and wetland ecosystems has become a hot issue in the field of wetland eco-hydrology research. The ecological conservation areas of wetlands in the lower Yellow River are chosen as the typical research area. The effect degree of the hydropower project on the eco-hydrological regimes is assessed quantitatively with eco-hydrology and related statistical methods based on the long term hydrological data. Through the quantitative remote sensing interpretation and sample surveys in the field observation, the evolution trends of wetland vegetation distribution and landscape pattern are analyzed and the influence degree of hydropower project on the wetland vegetation is ascertained. The modelling model containing hydrological process, landscape pattern and wetland vegetation is established. The quantitate relationship between the key eco-hydrological indicators and landscape pattern index and vegetation biomass is stipulated. The ecological flow under different ecological protection goals of wetlands in the lower Yellow River is put forward. The multi-objective optimization model of ecological operation is established combining the objectives about ecological protection of wetlands and other socio-economic indexes of hydropower projects in the Yellow River. The schemes of ecological regulation are proposed for the wetlands in the lower Yellow River. The study will provide scientific basis for ecological protection and restoration of wetlands in the lower Yellow River.

水文过程是湿地生态系统演替重要驱动力，水电工程建设运行在改变河流水文过程同时，也对湿地生态系统结构与功能造成重要影响。研究水电工程与湿地生态系统之间动态响应关系，已成为当前湿地生态水文学研究领域的热点问题。本研究选择黄河下游湿地生态保护区为典型研究区域，基于长序列水文数据，运用生态水文学和相关统计学方法，定量评估水电工程建设运行对湿地生态水文情势改变程度；通过定量遥感解译与实地样方调查观测，解析湿地植被分布与景观格局演变趋势规律，探明水电工程对湿地植被影响程度；构建“水文过程-景观格局-湿地植被”耦合模拟模型，厘定关键生态水文指标与景观格局指数和植被生物量之间量化关系，提出不同生态保护目标的黄河下游湿地生态需水过程；耦合湿地生态保护目标和水电工程调度其它目标，构建水电工程多目标生态调度优化模型，提出黄河下游湿地生态水文调控方案。研究将为黄河下游湿地生态保护以及开展生态修复工作提供科学依据。

黄河中下游湿地系统是黄河流域生态系统的重要组成部分，在调蓄洪水、维持河流生态系统良性发育、生物多样性以及区域生态环境良性循环等方面起着十分重要的作用。自1960年以来，黄河干流三门峡、刘家峡、龙羊峡、小浪底等大中型水利工程相继建成，河流的天然径流和泥沙过程由于不同时期的水库修建和调节运用发生了巨大的变化，同时也改变了黄河下游湿地植被以及景观格局，影响了黄河下游湿地生态系统健康。从维护黄河下游湿地生态健康角度出发，分析黄河上游来水和三门峡水库、小浪底水库调蓄双重影响下黄河中下游水沙演变规律，厘清了气候变化和人类活动对水沙影响贡献率大小；以遥感影像为基础，结合土地利用类型图、野外调查、实地考察结果划分黄河下游湿地景观类型，分析小浪底水库运行前后黄河中下游地区典型湿地面积与植被覆盖度的变化情况；确定了水沙演变和湿地植被演替相互关系；为黄河中下游地区的可持续发展和生态保护提供科学的理论支撑。.通过4年的研究，在国内外学术刊物发表学术论文11篇，其中SCI5篇，EI1篇；出版专著1部；发明专利6项；获奖励1项；培养硕士研究生3名；参加国内会议6次。总体上来看，较好完成了项目计划书中预期成果目标。该成果内容丰富，对于黄河高质量发展具有较强指导作用。