生态用地空间稳定性及其格局分析——以咸阳市为例

生态用地是生态空间规划与生态保护的最核心土地利用类型集合。利用生态用地指数及空间统计学方法，对陕西省咸阳市2000-2010和2010-2020两个时段的生态用地空间稳定性的数量与格局特点进行了分析。结果表明：（1）稳定性生态用地的空间分布呈现了北部数量多、中部数量少、南部关中平原极少的空间格局；在2000-2010和2010-2020两个时段，其面积从266935.14hm²增加到了275851.17hm²。（2）在2000-2010和2010-2020两个时间段内，全市的生态用地稳定性指数基本上都维持在26%-28%之间，其中以黄土丘陵沟壑区最高，在43%-45%之间，黄土台塬在14%-15%，关中平原区都在0.2%以下。（3）从生态稳定性指数的动态来看，20年间全市平均增幅为0.87个百分点，其中以黄土丘陵沟壑区增幅最大，后10年比前10年增加了1.61个百分点，关中平原区增加了0.02个百分点，只有黄土台塬区降低了0.15个百分点；生态用地稳定性指数的分级结果表明，其总体呈现低稳定等级区域在减少，而中、高稳定等级区域在扩大。（4）生态用地稳定性指数的局部空间自相关分析表明，整个市域以高-高聚集区和低-低聚集区为主，其市域面积占比区间分别为48%-49%和47%-48%，前者主要分布在北部的黄土丘陵沟壑区，后者主要分布在南部的关中平原区和中部的黄土台塬区。热点分析结果表明，具有统计意义的冷点空间主要分布在南部的关中平原区和中部黄土台塬区，而热点空间则以北部的黄土丘陵沟壑区为主，仅在该区域的东南角有极小部分属于冷点区域。

Ecological land and its spatial stability analysis-Taking Xianyang City as an example

Ecological land is the core set of several land use types in ecological space planning and ecological protection. In this paper, the stability index was put forward as a tool to measure the spatial stability of ecological land. Based on the village-level ecological land stability index from 2000 to 2010 and from 2010 to 2020 in Xianyang City, Shaanxi Province, the quantity and pattern characteristics of the stability of ecological land use were revealed, using transition probability matrix and spatial correlation statistics method. The results showed that:(1) according to land cover in 2000, 2010 and 2020, ecological land was mainly distributed in the northern Loess Plateau Hilly and Gully Region and the northern part of the central Loess Tableland, the southern Guanzhong Plain region was the most scarce. In the past 20 years, the total area of ecological land decreased by 4509.81hm², and in the last 10 years, the area of ecological land decreased by 3058.92hm², which was 2.11 times that of the previous 10 years. (2) The spatial distribution of stable ecological land presented the same as that of ecological land, and its area increased from 266935.14hm² in 2000-2010 to 275851.17hm² in 2010-2020. (3) In 2000-2010 and 2010-2020, the ecological land stability index of the whole city maintained 26%-28%, among which the Loess Hilly and Gully Regionbasically kept 43%-45%, Loess Tableland was 14%-15%, and Guanzhong Plain area was below 0.2%. From 2000-2010 to 2010-2020, the ecological land stability index increased by 0.87% in the whole city, in which the Loess Hilly and Gully Regionincreased by 1.61%, the Guanzhong Plain Region increased by 0.02%, and the Loess Tableland Region decreased by 0.15%. The classification results of ecological land stability index indicated that the areas with low stability grade were decreasing, while the areas with medium and high stability grade were expanding. (4) From the analysis of the spatial pattern of ecological land use stability, the local spatial autocorrelation analysis of ecological land stability index showed that, the whole city was dominated by high-high agglomerations and low-low agglomerations, accounting for 48%-49% and 47%-48% of the whole city area, respectively. The high-high agglomerations were mainly distributed in the Loess Hilly and Gully Region, while the low-low agglomerations were mainly distributed in the Guanzhong Plain Region, and the Loess Tableland region. Hot spot analysis showed that, cold spots region with statistical significance (on behalf of the low stability of ecological land) was mainly concentrated in the Guanzhong Plain and the Loess Tableland Region. The hot region (on behalf of the high stability of ecological land) was mainly concentrated in the loess Hilly and Gully Region.