1.State Key Laboratory of Coastal and Offshore Engineering,Dalian;2.National Marine Environmental Monitoring Center University of Technolog;3.y;4.National Marine Environmental Monitoring Center;5.State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology
National Key Research and Development Program of China(No.2017YFC0505901)
实现湿地内水文连通对黄河三角洲湿地生态系统的完整性具有重要意义。本研究利用Google Eearth Engine在大尺度上从湿地水体面积、整体水文连通指数、像元月均淹没频率对黄河三角洲湿地水文连通量化，并利用灰色关联进行驱动力分析；在淡咸水交互的典型区域尺度上选择水文网络连通指数进行分区水文连通分析。研究结果发现：1）整体上黄河三角洲湿地水体面积上升和整体连通性指数减少趋势，研究区域内发生了连通阻断，重度淹没和永久性淹没主要集中在浅海区域。2）黄河三角洲湿地水体面积和整体连通性指数均呈现季节性趋势,湿地水体面积变化驱动要素年平均气温>径流量>降水量>输沙量。3）依据水文连通评价标准，从区域尺度黄河三角洲湿地水文连通性30年一直保持中等水平。整体上黄河三角洲湿地水文连通性呈下降趋势，气温的变化对水文连通影响较大。该研究结果可为黄河三角洲湿地水文连通保护和修复提供参考。
Achieving hydrological connectivity within wetlands is important for the integrity of wetland ecosystems in the Yellow River Delta. In this study, at the large scale, this study used Google Eearth Engine to quantify the hydrological connectivity in terms of wetland water area, overall hydrological connectivity index, and average monthly inundation frequency. The driving force analysis was conducted using gray correlation; at the typical regional scale of fresh and saline water interaction, three hydrological network connectivity indices were selected for the zonal hydrological connectivity. The results of the study found that: 1) Overall the area of the Yellow River Delta wetland water area rose and the overall connectivity index decreased trend, connectivity blockage occurred in the study area. Heavy inundation and permanent inundation were mainly concentrated in the shallow sea area. 2) Both the area of wetland water and overall connectivity index of Yellow River Delta showed seasonal trends. Driving factor of wetland water area change:annual average temperature> runoff> precipitation> sediment transport. (3)According to the hydrological connectivity evaluation criteria, the hydrological connectivity of the Yellow River Delta wetlands has been maintained at a medium level for 30 years from the regional scale. The overall hydrological connectivity of the Yellow River Delta wetland was declining, and the temperature changes had a great impact on the hydrological connectivity. The results of this study can provide a reference for the conservation and restoration of hydrological connectivity in the Yellow River Delta wetlands.