为探究盐城市围填海空间格局的变化特征,选取1984~2015年Landsat 4/5/7/8影像数据,利用景观指数计算方法,对盐城市新增围填海的面积、强度、聚集度和质心等4个方面变化特征进行分析。结果如下：(1)1984~2015年,盐城市新增和侵蚀破坏围填海面积分别为95182.71 ha和1970.45 ha,且随时间变化围填海侵蚀破坏区不断向南扩张。1984~2015年,围填海利用类型经历了从已围待利用地为主到盐养用地为主的演变过程。(2)1984~2015年的3个时间段内港池蓄水围填海强度指数均较小,最大围填海强度指数仅为0.19 ha/km。建设填海造地、已围待利用地和盐养用地的围填海强度指数呈现不断上升的变化趋势,最大围填海强度指数分别为2.15,27.53和77.33 ha/km。农业填海造地的围填海强度指数呈现先上升后下降的变化趋势,最大围填海强度指数为18.51 ha/km；(3)1984~2015年,盐城市围填海各类型的聚集度指数均较高,平均聚集度指数高达96.98。盐城市围填海质心不断向东南方向迁移,说明盐城市围填海开发的重点区域逐渐向南迁移。%To explore the spatial pattern of reclamation in Yancheng City, we chose Landsat 4/5/7/8 data from 1984—2015 and analyzed the intensity, aggregation indices, and barycenter of the newly increased reclamation areas with a landscape-index-calculation method. The results show that (1) the newly increased and erosion areas were 95 182.71 ha and 1 970.45 ha, respectively, during 1984—2015. In addition, the erosion area tended to expand from north to south over time. The type of reclamation has transformed from unused marine reclamation land to salt and cultivation marine land during 1984—2015. (2) During 1984—2015, the intensity indices of reclamation were small, with a maximum of 0.19 ha/km. Intensity indices of developed marine land, unused marine land, and culti-vated marine land increased gradually with maxima of 2.15, 27.53, and 77.33 ha/km, respectively. However, the intensity indices of reclaimed agricultural marine land presents a trend, first rising then falling, and the maximum reclamation is 18.51 ha/km. (3) The aggregation indices of different types of reclamation during 1984—2015 in Yancheng City are higher than those during other periods, and the average of these indices is 96.98. In addition, the barycenter of reclamation shows a tendency to expand from northwest to southeast over time, which indicates that the main developing region of reclamation is moving from north to south.
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