不同尺度喀斯特地区土地利用变化研究

RESEARCH ON CHANGES OF LAND-USE IN DIFFERENT SCALE IN KARST MOUNTAIN

以贵州典型喀斯特地区贞丰县、北盘江镇、花江示范区作为研究样区,讨论了不同尺度喀斯特地区土地利用动态变化过程。结果发现:研究样区土地利用的数量变化主要表现在农用地与未利用地之间的增减变化,而且1997—2000年的土地利用变化速度比2001-2003年的快。在土地利用的结构变化上,北盘江镇园地所占比例增长、未利用地所占比例减少和贞丰县林地面积所占比例变化最大,花江示范区同北盘江镇的结构变化相似。在土地利用的程度变化上,三个研究区土地利用程度综合指数都有所提高,整体趋于平衡。县级尺度的土地利用程度综合指数大于镇级尺度,村级尺度的土地利用综合指数最小。三个研究区的景观偏离度呈有规律的缓慢增长趋势,表明人类活动对土地利用的影响逐渐加强。

This paper chooses three typical areas, Zhenfeng county, Beipanjiang town, Huajiang demonstration area as examples to study the dynamic process of land-use changes in karst area in different spatial scale. It shows that the land-use change in quantity or area has taken place mainly in the increase or decrease between agricultural land and uncultivated land. The changing speed of land-use during 1997 to 2000 is faster than that during 2001 to 2003.In the change of land-use structure, the increasing range of garden fields is the largest and the decreasing range of uncultivated lands is the largest in Beipanjiang, and the range of woodlands changes is the biggest in Zhenfeng. The change of land-use structure in Huajiang is similar to Beipanjiang. In the change of land-use level, the overall index of land-use level is high in all, and the whole tend is in equilibrium. But the overall index of land-use level in county-class is higher than that in town-class, and the village-class is the lowest. The landscape deviation at three sample sites has a trend of slow increase in regulation, which reflects the influence of land-use by human activities is being strengthened gradually.