黄河下游湿地演变与实测径流相关性研究

Correlation Analysis of Wetland Evolution and Measured Runoff in the Lower Yellow River

探索不同类型河道湿地面积与水文站实测径流量的相关性,为黄河流域生态保护修复和管理工作提供支撑。选择黄河下游花园口-利津河段为研究对象,基于1986、1990、2000、2010和2020年5期遥感解译黄河下游湿地的类型、面积和格局,分析湿地动态变化及原因,结合黄河下游重要水文站实测径流量数据,探索黄河下游不同类型河道湿地面积变化与径流相关性。结果表明:(1)河流水面湿地为黄河下游河段湿地的主要组成部分,占湿地面积的45.9%~65.9%;(2)黄河下游河段的湿地面积从20世纪80年代至今呈现萎缩趋势,面积减少约35.6%,但萎缩速度在不断减缓,湿地面积逐渐趋于稳定;(3)黄河下游游荡型、弯曲型和顺直型河段的湿地面积与径流量的相关性存在差异。游荡型和弯曲型河段河流水面面积与流量均呈正相关关系,但变化幅度不同,顺直型河段河流水面面积受流量的影响较弱,游荡型、弯曲型和顺直型河段滩地面积随径流量增大而减少,减少幅度各有差异。

The Huayuankou-Lijin reach of the lower Yellow River was selected for study in this research, and we explored the relationship between the wetland areas of different river channel types and the measured runoff at hydrological stations in the lower Yellow River. The objective was to provide support for ecological protection, restoration, and management in the Yellow River basin. Based on the remote sensing images of the Huayuankou-Lijin reach in 1980, 1990, 2000, 2010 and 2020, the types, areas, and distribution patterns of wetlands for the five periods were interpretated to explore the dynamic changes of wetlands and the factors driving the changes. Then, combined with the measured runoff data recorded at hydrological stations(Huayuankou, Jiahetan, Gaocun, Aishan, Luokou and Lijin) in the lower Yellow River, the correlation between wetland area changes and runoff in different types of rivers were analyzed. Results show that:(1) River surface flow wetlands were the primary type of wetland in the lower reach of the Yellow River, accounting for 45.9%-65.9% of the total wetland area.(2) Although the wetland area in the lower reach of the Yellow River has been shrinking since the 1980s, decreasing by 35.6%of the total area,the rate is decreasing and the wetland area is gradually stabilizing.(3) The correlation between river surface area and runoff differed with channel type in the lower Yellow River. In wandering and meandering sections, there was a positive correlation between the river surface area and runoff with different ranges in variation, while the river area of straight sections were weakly affected by runoff. The river beach areas of all channel types decreased with runoff, but to different degrees. The wetland areas of the three channel types remained stable up to a certain flow but increased with flow thereafter.