南京市区景观破碎化过程中的斑块规模结构动态

基于南京市1988、1998和2003年3期TM影像,将农田、林地、居民聚居地及在建用地按斑块面积分为16个级别,研究了景观破碎化过程中,不同级别斑块数量的变化情况。结果表明,农田面积持续萎缩,破碎度上升,中小型斑块数量以较稳定速度增长;林地总面积略有波动,大中型斑块数量较为稳定,而中小型斑块受城市化进程影响,数量高度不稳定;居民聚集地在1988~1998年以在原有基础上扩张为主,在1998~2003年出现了大量新斑块,且两个时段的各级别斑块数量增长率呈极显著负相关;在建用地数量迅速增长,土地利用更加规模化。以上表明,斑块类型和大小对斑块的稳定性及变化趋势均有影响。

Dynamics of patch size structure in landscape fragmentation process in Nanjing urban district

Based on three scenes of TM imagery in 1988,1998 and 2003,the patch size area of the farmland,forestland,resident area,and constructing area in Nanjing urban district was classified into sixteen levels,and the quantitative variation of different level patches in the process of landscape fragmentation was studied.The results showed that farmland displayed diminished area and increased fragmentation degree,with the number of small-to-medium sized patches increased steadily.Forestland had a little fluctuation in its total area,with a stable amount of medium-to-large sized patches but a greatly varied number of small-to-medium sized patches.Resident area expanded much based on the existed patches from 1988 to 1998,but new patches mushroomed from 1998 to 2003.Constructing area developed rapidly,and its land use scale enlarged.All of these indicated that both the type and size of patch had definite effects on the patch stability and its change trend.