内蒙古典型草原土壤斥水性有机物质促进机理

项目名称： 内蒙古典型草原土壤斥水性有机物质促进机理

项目编号： No.41471198

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 地质学

项目作者： 阿拉木斯

作者单位： 中国农业科学院草原研究所

项目金额： 90万元

中文摘要： 土壤斥水性是水分不能或很难湿润土壤矿物质颗粒表面的物理现象，目前对土壤斥水性原因与机理缺乏了解。本研究以内蒙古典型草原为例，在调查了解土壤斥水性空间变化、季节变化和土壤剖面变化的基础上，深入研究土壤斥水性与土壤理化及生物学性质、植被、优势植物疏水成分、放牧强度、草原退化等之间的内在和外在联系。重点研究斥水性土壤有机物质组成成分和特性，以及在土壤团聚体中分布特点与变化规律；主要优势植物根茎叶中疏水性有机物质组成成分及其在土壤中的分解转化过程，土壤斥水性与微生物群落结构及活性的关系。以期寻找:(1)能够指示土壤斥水强度的土壤有机物质指标，(2)建立基于土壤斥水性的典型草原土壤有机质质量评价指标与标准，(3)提出基于降低土壤疏水性有机物质含量，增强土壤亲水性的植被种群结构模式。

中文关键词： 土壤有机碳组分；土壤腐殖质；结构分析；土壤腐殖质功能；土壤腐殖质结构

英文摘要： Soil water repellency is a physical phenomenon resisting wetting, which greatly reduces plant production and induces in environmental and ecological risks as well. There is little understanding on the reasons and mechanisms inducing soil hydrophobicity. We will use the steppe grassland of Inner Mongolia as a study case. We will survey the natures of soil hydrophobicity in the steppe. The spatial and seasonal changes of soil repellency will be involved in the soil with difference degrees of hydrophobicity. The links will be identified between soil hydrophobicity and soil physical, chemical and microbiological parameters, vegetation, grazing intensity and soil degradation as well. It will be investigated for the composition, natures and distribution within soil aggregates of the organic components which are responsible for soil repellency. The hydrophobic compounds will be assayed for the advantageous grasses. And the contribution of these grasses to soil hydrophobicity will be studied through a lab experiment. One test will touch the microbiological mechanism of soil repellency. The aim of this research is : 1) to identify the soil organic components indicating soil hydrophobicity; 2) to establish the method and index for evaluating organic matter equality of the steppe grassland soil based upon soil repellency; 3)to bring forward a vegetation model for reducing soil repellency, but enhancing soil hydrophilicity.

英文关键词： soil organic carbon fractions;soil humus;structural analysis;soil humus function;soil humus structure