大沽河流域滨海湿地景观格局变化及其驱动机制

Effects of human activities on landscape alteration and aquatic environment of coastal wetland in Dagu River Basin

以大沽河流域滨海湿地为研究区域,以2000、2010及2019年的Landsat 5 TM和Landsat 8 OLI遥感数据为数据源,提取大沽河流域滨海湿地信息,采用训练分析法和景观格局指数的时空分异规律,分析不同时期人类活动对滨海湿地景观格局变化的影响。结果表明,2000-2019年间湿地、水体总面积变化较小,自然湿地景观面积整体呈现逐年增加的趋势,而人工湿地景观面积整体呈现逐年减小的趋势。大沽河河道在近20年间总体河流面积增加,河道变宽,大沽河流域滨海湿地总面积整体变化较小,其中,自然湿地景观中除滩涂湿地景观面积逐年减小外,湖泊、浅海水域、季节性河流和永久性河流湿地景观面积均增大。大沽河流域滨海湿地的斑块密度指数和斑块破碎化指数均呈现出先增后降的趋势。围垦、人口增长、城镇化发展、污染、海水入侵和环保举措等人为因素是引起大沽河流域滨海湿地面积和景观格局变化的主要驱动因素。

The information of coastal wetland of Dagu River basin,Qingdao,Shandong,East China,was extrac-ted from long-term series of Landsat 5 TM and Landsat 8 OLI remote sensing data of 2000,2010,and 2019.The effects of human activities on the alteration of coastal wetland landscape in different periods were analyzed by data training analysis and spatio-temporal differentiation of landscape pattern index.Results show that the total area of wetland and water body changed slightly from 2000 to 2019,and the natural wetland landscape area showed a trend of increasing year by year,while the constructed wetland landscape area showed a trend of de-creasing year by year.In recent 20 years,the river area of Dagu River has increased and the river channel has be-come wider.The total area of coastal wetland in Dagu River basin changed a little as a whole.In the natural wet-land landscape,except for the wetland area where tidal flat decreased year by year,the wetland area of lakes,shal-low sea waters,seasonal rivers,and permanent rivers all were increasedThe patch density index and patch frag-mentation index of the coastal wetland increased first and then decreased in Dagu River basin.Reclamation,popu-lation growth,urbanization,pollution,seawater intrusion,and environmental protection measures are the main factors and forces for the alteration of the coastal wetland area and landscape pattern in Dagu River basin.