基于GIS和LSA的林地质量评价与保护分区

合理划定林地利用保护分区,对于稳定森林资源,维持生态平衡,协调经济建设与生态文明建设起到积极指导和规范作用.论文以海南省屯昌县为例,在科学评价林地质量的基础上,采用局部空间自相关分析法(LSA),探索林地质量在空间上的分布特性,耦合林地自然条件,社会经济及其空间属性,以作为林地保护分区的依据.结果显示:屯昌县林地质量分值在[5.40, 8.56]之间,整体水平中等偏上,内部差异性较小,其中,高等别林地主要分布在南坤镇与枫木镇交界处以及西昌镇西南部,低等别林地主要分布在坡心镇及南吕镇;全县林地质量在空间分布上表现出较强的正相关性,存在一定的空间聚集性特征;基于林地质量局部空间自相关分析的林地保护分区方案与林地质量评价结果基本吻合,可将全县分为重点保护区,积极保护区和一般保护区,不同保护区根据自相关类型的差异可采取不同的管护措施.该研究将空间属性纳入到林地保护分区方案的制定中,拓展了林地保护分区的手段,可为合理制定林地利用规划提供科学依据和思路借鉴.

Quality Evaluation and Protection Zoning of Forest Land Based on Local Spatial Autocorrelation

Designing a suitable zoning scheme for forest land protection can play active role in guiding and regulating the sustainable usage of forest resources, the balance of ecology and the coordinated development of economic and ecological civilization. This paper takes the spatial distribution properties of forest land into account when formulating a scientific protection scheme of forest land, taking the Tunchang County locating in Hainan Province as an example. Firstly, the quality of forest land was evaluated scientifically, and the local spatial autocorrelation analysis was introduced to explore the spatial characteristics of forest land quality. Then, the natural and socio-economic properties of forest land are combined with the spatial distribution characteristics to form the basis for protection zoning of forest land. Results indicate that: 1) the quality value of forest land varies from 5.40 to 8.56 in the whole county with little variation, overall being in moderate and upper levels. In detail, 13.71% of the forest land is the first-grade land which mainly locates in the southwestern Xichang Town and along the border between Nankun and Fengmu Town, while 18.35% of the forest land is the fourth-grade which mostly spreads over Poxin and Nanlü Town. The second-grade and third-grade forest land take 32.57% and 35.26% respectively which disperse all over the county. 2) The index of Moran's I is 0.531 7, which means strong positive spatial autocorrelation of forest land quality. Therefore, it reveals that the forest land quality has a certain spatial clustering characteristics in the county. 3) According to the local spatial autocorrelation analysis, the protection scheme of forest land in Tunchang County was designed. It is consistent with the quality evaluation results basically, which divides the forest land into key protected region, active protected region and general protected region. Different protection measures can be implied in different kinds of protected regions. In conclusion, taking the spatial distribution property of forest land into consideration in the design of protection zoning is a method for forest land protection division, and it provides a new idea for rational forest land use planning.