2001—2018年鄱阳湖区土地利用及景观格局时空演变

The Spatial-Temporal Evolution Analysis of Land Utilization and Landscape Pattern in Poyang Lake Area from 2001 to 2018

基于2001年、2006年、2011年、2016年、2018年5期鄱阳湖区土地利用数据,采用土地利用转移矩阵、景观格局指数和移动窗口法,定量分析了鄱阳湖区的土地利用变化及景观格局演变.结果表明:(i)鄱阳湖区的土地利用类型呈环状分布,以鄱阳湖为核心向外围过渡为耕地、林地等主要地类;人类活动及生态退化的双向递推导致城市空间面状扩张和林地流失严重;(ii)在土地利用动态转移方面,这18年间鄱阳湖区约17.63%的土地发生了转移,林地转化为耕地、耕地转化为林地、林地转化为草地成为主要转化类型;(iii)从斑块类型水平看,林地和耕地是鄱阳湖区的优势景观类型,2者置换趋势明显;从景观水平看,鄱阳湖区的景观破碎化程度加剧;(iv)鄱阳湖区南部的景观分离度高于北部,水陆交错带的景观分离度较高,形成了环鄱阳湖水域的景观分离圈.

Based on the land utilization data in Poyang Lake area in 2001,2006,2011,2016,and 2018 year,the land utilization transfer matrix,landscape pattern index and moving window method are used to quantitatively analyze the land utilization change and landscape pattern evolution of Poyang Lake area.The results show that the land utilization types of Poyang Lake area are distributed in a circle,with Poyang Lake as the core to the periphery as the main land types such as cultivated land and forest land,the bidirectional recursion of human activities and ecological degradation lead to urban spatial expansion and the loss of forest land.In terms of land dynamic use transfer,the land area that has changed in the Poyang Lake area in the past 18 years accounts for 17.63%of the total area.The main conversion types are forest land output as cultivated land,cultivated land output as forest land,and forest land output as grassland.From the perspective of the patch type level,forest land and cultivated land are the dominant landscape types in the Poyang Lake area,and the replacement trend between them is obvious.From the landscape level,the degree of landscape fragmentation in the Poyang Lake area is intensified.The landscape separation degree in the south of the Poyang Lake area is higher than that in the north,and the landscape separation degree in the water-land interlaced zone is high,forming a landscape separation circle around the Poyang Lake.