1995—1999年黄河三角洲东部自然保护区湿地景观格局变化

基于1995和1999年的Landsat TM遥感影像，结合地理信息系统技术，分析黄河改道清8汊（1996年）前后的1995—1999年黄河三角洲东部自然保护区（位于黄河现行流路入海口处）湿地景观格局的变化特征，以及影响湿地景观格局变化的驱动因素.结果表明：1995—1999年，保护区湿地仍以天然湿地为主，人工湿地比重极小，期间非湿地面积大幅增加，而天然湿地和人工湿地面积则呈下降趋势，其中，裸露淤泥质滩涂和沼泽湿地面积明显萎缩；尽管保护区湿地景观类型、形状、结构的变化程度不均一，且各景观类型在空间分布上的团聚程度变化不均衡，但总的看来，保护区景观整体结构趋于复杂化，破碎化程度有所加深，内部各景观类型从大块连续的镶嵌分布向小块离散分布转变；影响保护区湿地景观格局变化的主要因素有3个：黄河改道、黄河断流和人类活动.

Changes of wetland landscape pattern in Eastern Yellow River Delta Nature Reserve from 1995 to 1999.

Based on the 1995-1999 Landsat TM images and geographic information systems, this paper analyzed the change characteristics of wetland landscape pattern in the Eastern Yellow River Delta Nature Reserve (an inlet of current flow path emptying into the sea), and related driving factors during the past few years pre and post the Yellow River diverting into Qing 8 anabranches in 1996. In 1995-1999, natural wetland was still the matrix of the wetlands in the Reserve, while constructed wetland only had a very small proportion. A substantial increase was observed in the area of nonwetlands, and a decline was found in the area of natural and constructed wetlands, among which, bare muddy tidal flats and marshes shrank significantly. Though the landscape types in the reserve had no homogeneity in the changes of shape and structure, and their aggregation degree in spatial distribution varied, the overall landscape structure became more complicated and fragmented, and the distribution of inner landscape types converted from continuously large blocks to discretely small patches. River diversion, flow break, and human activities were the main three driving factors leading to the changes of the wetland landscape pattern in the reserve.