河口潮滩湿地景观格局变化及其受圈围开发影响的分析——以崇明东滩为例

以崇明岛2期SPOT遥感图像为数据源,以遥感图像处理和分类技术及景观格局分析软件FRAGSTAS为研究手段,分析了近十几年来的景观变化和人类圈围滩涂等活动对研究区景观的影响。结果表明,人类围筑海塘和开发活动导致景观在以海塘为界的不同区域逐渐分异,各区域具有各自独特的景观格局;人类大规模的干扰活动一方面在直接改造着景观,在92塘内开垦区域呈现出集约农业景观,另一方面也间接影响了景观,在92塘和98塘之间已圈围而未开垦区域内导致了严重的芦苇带破碎化,在98塘外的自然潮滩区域导致了潮沟减少和退化、盐沼草滩周围斑块类型的丰富性和均匀性下降及潮滩湿地景观整体异质性下降等后果。

Analysis of the Landscape Pattern Change and the Influence Caused by Diking and Development Activities in Estuarine Tidal Flat Wetland

By using two-period SPOT image of Chongming Island as information resource and with the support of remote sensing image classification technique and a landscape indices computing software FRAGSTAS,the landscape pattern of this area was examined.Furthermore,the landscape change and the impact of anthropogenic activities such as diking on the landscape were analyzed.The results showed that diking and other development activities led to the landscape differentiation of the zones distinguished by sea walls,which obtained their particular characteristics gradually.The anthropogenic activities altered the landscape directly,and affected it indirectly at the same time.The result included the tidal flat landscape's conversion to intensive cultivation landscape within the diked area enclosed by 92-bank,the serious fragmentation of reed marsh within the diked but not assarted area enclosed by 92-bank and 98-bank,the reduction and degradation of tidal creeks,the decrease of patches' richness and evenness around the salt marsh,and the decline of landscape heterogeneity in the natural tidal flat wetland area outside the 98-bank.