回汉聚居区土地利用变化对比分析

Comparative Analysis of Land Use Change in Han and Hui Nationality Settlements

利用1978~2015年Landsat数据,以宁夏盐池县和同心县为例,对回汉聚居区近40 a土地利用变化时空特征进行了对比分析。结果表明,(1)盐池、同心两县耕地、林地面积总体呈增长态势,盐池县耕地、林地面积分别增加了5.18×10~4 hm^2和6.67×10~4 hm^2,同心县耕地、林地面积分别增加了2.66×10~4 hm^2和3.28×10~4 hm^2。两县草地面积以1987年为转折点,之前大幅减少,而后持续增加。(2)同心县土地利用程度指数高于盐池县,均呈增大趋势。1978~1996年,盐池县土地利用集中化程度高于同心县,而2007~2015年,同心县土地利用集中化程度超过了盐池县,土地利用类型主要集中于草地、耕地和林地,呈现以农牧为主的土地利用格局。(3)两县土地利用信息熵均呈上升趋势,表明土地系统的有序化程度逐步降低。

Based on the remote sensing data from 1978 to 2015, this paper compared and analyzed the spatio-temporal characteristics of land use change between Yanchi and Tongxing County in Ningxia Hui Autonomous Region over the past 40 years. The results show that:(1) over the past 40 years, the cultivated land and forest land area show a growing tendency overall in both Yanchi and Tongxing County. Yanchi County increased cultivated land and forest land area by 5.18×10~4 hm^2 and 6.67×10~4 hm^2, while the cultivated land and forest land area of Tongxing County increased 2.66×10~4 hm^2 and 3.28×10~4 hm^2. The grass land area decreased before 1987 in both Yanchi and Tongxing County, but after 1987, the grass land area increased continuously.(2) The integrated indexes of land use in Yanchi and Tongxing County both have a tendency of increase, but the integrate index of Tongxing County is obviously higher than Yanchi County. Analyzing the land use concentration degree by Lorenz curve, it shows that the concentration degree of Yanchi County is higher than Tongxing County from 1978 to 1996, while from 2007 to 2015 it is just contrary. The main land use types are grass land, cultivated land and forest land both in Yanchi and Tongxing County.(3) The information entropy of land use shows an increasing tendency in Yanchi and Tongxing County, which shows that the order degree of land system is decreased gradually.