基于森林资源二类调查数据的黄龙山森林景观分类

以黄土高原黄龙山林业局蔡家川林场为例,选取优势树种(组)、海拔、坡度和坡向作为分类因子,利用ArcGIS,按分类因子分割林场森林景观空间为56 672个空间基本单元,建立起量化的、与植被和环境因子相关的森林景观空间基本单元数据库,在此基础上采用聚类分析方法把所有基本单元聚合为不同相似水平上的景观要素类型,结合生态特征和经营需要对聚类结果进行分析,最终确定了7种景观要素类型,生成了景观要素类型斑块图。斑块特征和空间格局分析结果表明:该林区森林景观中以小斑块要素比例最大,中、小和巨大斑块数占总斑块数的91.91%。栎类林具有最大的面积、平均斑块面积、斑块周长、最大生境面积和内部生境指数,是该地区受人为干扰相对较小、仍需要进行保护的景观要素类型。在森林经营中,应注意保护大型斑块的景观要素类型。景观多样性和均匀度较高,优势度相对较低,表明景观异质性好。

Classification of Forest Landscape Components Based on Forest Resource Inventory Data for Huanglongshan Frestry

With the data of Caijiachuan Forest Farm of Huanglong mountain Forestry Bureau in Shaanxi Province,the quantitative and spatial database of vegetation and environment factors was es- tablished for the purpose of classification. Dominant tree species（or groups）, elevation, gradient and slope--aspect were selected as influential factors for classification, and the spatial range of the forest farm was segmented into 56 672 elementary units by the projection division of vector layers of the 4 in- fluencing factors with ArcGIS. Cluster analysis was then conducted with the 56 672 elementary units and 7 types of landscape components were determined as the key elements of forest landscape composi- tion, and the related patch map was created respectively. Results of patch features and patterns analy- sis showed that：the small class of the landscape patch constituted the majority,and the small ,middle and huge classes of landscape patch accounted for 91.91% of the total patches. The oaks occupied the biggest area and also are of the longest average patch area, the longest patch perimeter and the inner habitat index,etc. , showing a relatively fewer man--made interference and then should be carefully protected in the process of forest management. The landscape diversity index and evenness index are higher, while dominance of the whole district is low, indicating that the spatial heterogeneity is good.