作为外来物种的樟子松人工林在生长发育过程中对引种区土壤的物理、化学性质会产生深刻影响。基于林龄和密度变化的沙地樟子松人工林土壤特性演变规律研究揭示樟子松人工林在生长发育过程中对沙地土壤变化过程的作用规律。项目将10-60年跨度的沙地樟子松人工林作为研究对象，从樟子松人工林不同林龄入手，通过现场调查、取样、实验室测定、数据处理、综合分析，揭示樟子松人工林在整个生长发育阶段对沙地土壤理化性质的影响规律；在每个林龄阶段，通过研究樟子松人工林林分密度变化对沙地土壤物理、化学性质的影响，揭示林分密度对沙地土壤理化性质变化的作用规律；通过研究沙地樟子松人工林在不同林分密度下的生长发育状况，揭示沙地樟子松人工林生长发育与土壤特性变化的相关关系。从而达到揭示樟子松人工林在整个生长发育阶段不同林分密度下对土壤特性的影响过程，为沙地樟子松人工林的合理经营提供理论支撑。

As an alien species, Pinus sylvestris var. mongolica planted forest in the process of growth and development will have a profound impact on soil physical and chemical properties of the introduced area.Studying on soil characteristics evolution of Pinus sylvestris var. mongolica planted forest in sandy land based on changes in forest age and density, revealed the role and law of Pinus sylvestris var. mongolica planted forest in the growth and development for the sand land soil.The research object of this project is 10-60 years of Pinus sylvestris var. mongolica planted forest. Starting with different ages of Pinus sylvestris var. mongolica plantations, discovered that the effects law of Pinus sylvestris var. mongolica planted forest in the whole growth and development stage on the sand land soil physicochemical properties, through field survey and sampling, laboratory determination, data processing and comprehensive analysis. In each stage of forest age, the study has shown that different density plantations of Pinus sylvestris var. mongolica have an impact on the sand land soil physicochemical properties and discovered that the effects law of stand density on changes of physical and chemical properties of the sandy soil.By analyzing the growth status of Pinus sylvestris var. mongolica plantation in sandy land in different stand densities, concluded the correlation between growth of Pinus sylvestris var. mongolica and changes of soil characteristics.The process of revealing different density of Pinus sylvestris var. mongolica plantations throughout the growth stage of the impact on soil properties has provided theoretical support for the rational management of Pinus sylvestris var. mongolica plantation.