水沙变异对黄河三角洲湿地面积演变的影响

Effect of flow and sediment variation on the Yellow River Delta wetland area evolution

水沙过程是塑造湿地生态系统结构与功能的重要驱动力,控制着湿地的形成与演化。利用1976年-2014年近40年黄河三角洲湿地面积变化的遥感影像数据,系统分析湿地面积、湿地重心和南北区域湿地类型的动态变化进特征。研究结果显示:近40年来黄河三角洲人工湿地面积增加约1 000倍,自然湿地面积呈波动下降趋势,减少约41.9%;芦苇、滩涂、养殖及盐田湿地等典型湿地面积重心整体由西北向东南方向位移;南北部区域的湿地类型的演变出现呈现较为明显的差异特征,其中北部芦苇湿地、滩涂湿地面积呈减少趋势,南部芦苇湿地面积整体呈增加趋势,滩涂湿地面积先增加后减少。研究结果可为水沙变异条件下黄河三角洲湿地生态系统的保护与修复提供科学依据。

Flow and sediment process controlled the formation and evolution of wetlands.They were recognized as significant driving forces of shaping structure and function of wetland ecosystems.In this paper,the dynamic changes were studied about the area,center of gravity and wetland types of delta wetland,based on the remote sensing data of the Yellow River Delta wetland area from 1976 to 2014.The results showed that constructed wetland area had remarkably increased 1000 times.However,natural wetland area had reduced 41.9% with fluctuation during the 40 years.The gravity center of reed,beach-land,culture and salt field wetlands had shifted from northwest to southeast.There were significant difference between south and north of wetland evolution.Northern reed and beach-land areas had a decreasing trend.While reed wetland area showed an increasing trend,and beach-land area firstly increased,then decreased in southern.The results may provide a scientific basis for protection and restoration of the Yellow River Delta wetland ecosystem under the condition of flow and sediment variation.