中文摘要：

通过调查取样,对比分析了海南岛中部山区天然林地及林地转变为橡胶林后的土壤物理和化学性质差异。结果表明：（1）不同林地对砂、粉粒和黏土粒度分布的影响显著,天然林地0～30cm、30～60cm和60～120cm三个深度的土壤的物理性黏粒含量均高于人工林地。（2）天然林地和人工橡胶林三层的土壤容重和田间持水量均存在显著差异,天然林地0～30cm和30～60cm的土壤田间持水量大于人工橡胶林。（3）两种林地的上、中、下三层土壤的有机质、全氮、碱解氮均有很大差异。天然林地土壤上层（0～30cm）有机质、全氮、全磷和速效磷含量均高于人工橡胶林。（4）人工橡胶林的土壤C：N和C：P比均大于天然林地。

英文摘要：

Natural forest and artificial rubber plantation are the dominant land covers in the central mountainous areas of Hainan.In this paper a comparative study is conducted on soil physical and chemistry properties for the two different forests.The results show that：1）Different forests significantly affect the sand,silt and clay contents.The contents of physical clay particle in natural forest are higher than those in rubber plantation at the layers of 0-30cm,30-60cm,and 60-120cm in depth.2）Soil bulk density and field capacity significantly differ in the different forests.Field-moisture capacity in rubber plantation is lower than that of natural forest at layers of 0-30cm and 30-60cm.3）There are obviously differences in the two kinds of forests for soil organic matter,total nitrogen,and available nitrogen.The contents of soil organic matter,total nitrogen,total phosphorus and available phosphorus in natural forest are greater than those in rubber plantation.4）The ratios of soil nutrients（C﹕N and C﹕P）in artificial rubber plantation are larger than those in natural forest.