珠江河口形态变化下湿地生态流量核算方法研究

保障适宜生态流量是维持和恢复河口湿地生态系统健康的关键性因素。现有生态流量核算方法缺乏考虑河口形态变化下生态流量规律的改变机制，应用于高强度人类干扰环境时存在局限性。本项目以珠江河口陆海交互作用下近岸水域-潮间带湿地为典型研究区，开展河口形态变化下湿地生态流量规律及核算方法研究：首先基于遥感解译、GIS空间分析、元胞自动机模型等分析近几十年来河口湿地格局和形态结构的演变趋势，揭示长时间尺度河口湿地演变对水文、水质、形态结构的响应机制；进而兼顾识别的关键驱动因子，构建以不同形态特征为边界条件的序列水动力-食物网动态耦合模型，阐明河口湿地生态系统结构和功能对淡水输入及局地形态变化的响应及长期适应机制；最终通过情景分析和突变检验方法确定不同形态特征下维持河口湿地生态系统动态稳定的适宜生态流量过程，提出适用于高强度人类干扰环境的河口湿地生态流量核算方法，为河口湿地生态系统的保护与修复提供科学依据。

Determining appropriate environmental flow is a key factor in maintaining and restoring health of the estuarine wetland ecosystem. However, the existing environmental flow assessment methods usually take historical or natural flow regime as the template target and lack of consideration on human activities induced morphological structure alteration. It makes them have limitations when applied to high-intensity human interference environment, especially in the estuarine regions. The proposed study takes the coastal shallow water-intertidal wetlands formed by the land-sea interaction in the Pearl River Estuary as the typical research area. Firstly, we analyze the evolution trend of estuarine wetland and morphological structure pattern in recent decades based on remote sensing interpretation, GIS spatial analysis and cellular automata model, and reveal the response mechanism of long-term estuarine wetland evolution to hydrology, water quality and morphological structure. Then, by further coupling the sequence hydrodynamic model with different morphological structures as the boundary conditions, we are to build an estuarine hydrodynamic-food-web model to determine the estuarine eco-hydrological response and adaptation process at ecosystem structure and function level, and quantify the ecological effects of upstream reservoir operation induced freshwater inflow alteration and regional human activities induced local morphological structure changes. Finally, appropriate environmental flow to maintain dynamic stability of the estuarine wetland ecosystem under different morphological characteristics are determined based on scenario analysis and mutation test method. The proposed study will enhance our theoretical understanding of the eco-hydrological response in high-intensity human interference regions, which has important theoretical and practical implication for the protection and restoration of estuarine wetland ecosystem.