基于生态保护格局的塞罕坝森林景观特征分析

Analysis of landscape characteristics of forests in Saihanba based on ecological protection pattern

以塞罕坝地区森林资源二类调查资料等信息为基础,利用Arcgis和Fragstats软件,从土地利用类型、优势树种和树种龄组3个角度,对森林景观的空间结构特征、斑块及景观水平上的空间异质性进行分析。结果表明:有林地占景观面积的80.39%,作为土地利用类型中的主要景观要素主导着土地利用类型,在森林景观中占据绝对优势,对景观整体结构、功能及其变化的控制作用较强;森林景观中优势树种和龄组景观的优势度不明显,空间结构较为复杂,斑块破碎化程度较高,连通性较差;优势树种以华北落叶松、桦树和樟子松为主,其面积分别占景观面积的41.51%、18.95%、10.22%,多种阔叶树在该地区以培育防护林和特种用材林为目标,虽景观面积小,多数低于1 000hm^2,破碎化程度高,但它们提高了该地区树种多样性;各龄组景观结构不尽合理,成、过熟林景观面积占比极低,分别为3.19%和0.22%。塞罕坝地区土地利用类型景观格局有利于维持和稳定森林生态环境,但优势树种和龄组景观格局有待进一步改善。

Based on the forest resources inventories and other information,the landscape spa tial characteristics and heterogeneity were analyzed in Saihanba by using Arcgis and Frag stats. The landscape spatial characteristic and heterogeneity were studied in terms of landuse types, dominant tree species and age groups. Results showed that areas of forest land ac counted for 80.39% of landscape, which was the main landscape element and dominant in whole land use types. Forest land occupied an absolute advantage in the whole landscape, and had a strong control over the whole structure, function and change in landscape. In the forest landscape, the dominance of dominant species and age groups was not clear, the spatial structure was complex, the patch fragmentation was high, and the connectivity was poor. The dominant tree species were mainly included Latin principis rupprechtii, Pinus sylvestris vat. mongolica and Betula L. ,and the proportions of these patch areas in the landscape were 41.51%, 18. 95% and 10. 22%, respectively. Many broad leaved trees in this area were cultivated for shelterbelts or special timber forests. The species diversity was increased in this region, although their landscape areas were small, with majority less than 1 000 hm2 and high degree of fragmentation. The age group landscape structure was not reasonable, and proportions of mature and over mature forests were very low, which were only 3.19% and 0.22%, respectively. Landscape pattern in Saihanba area was conducive to maintaining and stabilizing forest ecological environment, and the landscape structure of dominant tree species and age groups needed further improvement.