河北省平山县卸甲河流域各土地系统植被的比较研究

以河北省平山县卸甲河流域作为个例研究，划分了８个土地系统。在研究了各土地系统土地利用类型结构的基础之上，进一步比较了它们之间植物群系（林）的分布：植物种数量，乔木、灌木及草本植物状况，以及植物群系的组成结构。各土地系统之间差别很大。研究说明，封山育林、植树造林恢复植被，以及保护天然林，是保护生物多样性唯一有效的办法。另一方面，也说明生态土地分类注意人类影响程度和土地利用，更加易于和土地分类规划相结合

VEGETATION COMPARISON OF DIFFERENT LAND SYSTEMS IN XIEJIAHE RIVER VALLEY,PINGSHAN COUNTY,HEBEI PROVINCE

Land system is the basic unit of ecological land classification which is different from the site classification.The later had been known for a long time.The ecological land classification is based on the landscape ecology.In this system,the land is treated as the landscape mosaic.In this paper,with case study,the eight land systems were classificated in Xiejia river valley.Based on researches,some differences in the plant formations about fields had been compared.The author demonstrate that closing hillsides to facilitate afforestation,planting tree,and recovering vegetation,specially conserving natural forest are effective measures for conserving the biological diversify.Meanwhile,the degree of mankind's impacts and land use had been considered,so the ecological land classification is easily combined with land program.