汕头市海岸带湿地变化及驱动因素分析

Analysis on the change and driving factors of coastal wetland in Shantou city

本研究利用多期Landsat遥感影像数据,以人机交互解译及GIS分析等手段,获取了20世纪80年代以来汕头市海岸带湿地分布情况,参照湿地分类系统将汕头市海岸带湿地分为自然湿地和人工湿地两大类(一级分类),并在此基础上分为浅海水域、河流、湖泊、海岸/滩涂、红树林、水库/坑塘、水田、盐田、养殖池塘9种湿地类型(二级分类);利用单一湿地类型动态度、湿地转移矩阵和相关性分析研究9个时期汕头市海岸带湿地的变化特征和影响因素。结果表明,1982—2020年,汕头市海岸带湿地总面积略微增加,面积增加了19.08 km^(2),自然湿地面积明显萎缩,面积减少了51.18 km^(2),人工湿地面积显著增长,面积增加了70.26 km^(2),海岸带湿地生态系统退化明显。其变化的主要驱动力来自汕头市快速城镇化进程中发生的滩涂围垦、填海造陆、围海围河养殖、渔港码头以及水利设施修建等一系列人为活动,其次,区内主要河流输沙量以及海平面上升对汕头市海岸带湿地变化也有一定影响。

In this study,according to the human-computer interactive interpretation and GIS analysis,the distribution of coastal wetlands in Shantou city was obtained since 1980s by analyzing the multitemporal landsat remote sensing image data.According to wetland classification system,Shantou coastal wetland was divided into natural wetlands and constructed wetlands(first classification),including 9 types.They were shallow sea areas,rivers,lakes,beaches/coastal,mangroves forest,reservoirs/ponds,water fields,salterns and aquaculture ponds(secondary classification).The variation characteristics and the influencing factors of coastal wetlands in Shantou city were analyzed by dynamic degrees of single wetland type,wetland transition matrix and correlation analysis.The results showed that:from 1982 to 2020,the coastal wetlands in whole area were increased slightly by 19.08 km^(2).The natural wetlands shrank significantly with a total area loss of 51.18 km^(2),while the constructed wetlands expanded significantly,with a total area increase of 70.26 km^(2).The main driving force of the change came from a series of human activities such as tideland reclamation,land reclamation,sea reclamation and river aquaculture,construction of fishing port wharf and water conservancy facilities in the rapid urbanization process of Shantou city.Secondly,the changes of sediment discharge and sea level rise of the major rivers also played a certain role in the wetland change.