盐城滨海湿地景观变化分段研究

Study on Landscape Changes at Various Segments of Yancheng Coastal Wetlands

在ERDAS、ArcGIS等软件支持下,利用3S技术将1期研究区植被分布图和3期遥感影像,提取出4期盐城滨海湿地景观分布图,并对这4期的湿地景观属性数据进行分段对比,即按照控制研究区湿地景观分布的不同影响因素,将研究区从北向南分为3段区域进行对比分析。结果表明:盐城滨海湿地在1980—2008年期间,自然景观,包括河口水域、盐蒿滩、芦苇沼泽、互花米草滩等面积减少41 692.8 hm2,减少了49%。人工景观,包括养殖水域、盐田、建设用地、耕地等面积增加97 890.4 hm2,增加了180%;控制三个区域湿地景观变化的主要原因分别表现为:侵蚀作用、侵蚀淤积混合作用和淤积作用;控制整个研究区湿地景观变化的主要人为原因是围垦。

By means of the ERDAS and ArcGIS softwares and the 3S technology, the landscape distribution informations respectively corresponding to 4 time periods are ex tracted from a vegetation map and 3 remote-sensing images to compare with each other of the 4 time peariod. The studied wetland area can be divided into 3 segments which are dependent upon the causative factors for the landscape changes. The 3 segments can be put in geographic order from north to south . Also the 3 segments are compared with each other. It is learnt from the analysis results that the landscape was changed in the period from 1980 to 2008. The natural landscape area, including estuary area, salt Artemisia beach, reed marsh, and Spartina aherni flora marsh, etc became 49% decreased in the period, and the decreased area was as much as 41692.8 hm^2. The artificial landscape area, including fishery cultivating waters, salt pans, land used for construction, and land used for agriculture, etc became 180% increased, and the increased area was as much as 97890.4 hm^2. The causative factors for the landscape change respectively in the 3 segments are the erosion only, the joint effects of erosion and deposition, and the deposition only. The main factor for the artificial change is the reclamation.