中文摘要：

Horqin 沙的陆地(HSL ) ，在东北中国的半干旱的 agro 牧剧交错群落的最大的沙的陆地，在过去的世纪期间服从于 desertification。在反应，并且到控制 desertification，管理实现了三北方的 Shelter/Protective 福雷斯特程序，世界最大的生态的重新造林 / 造林恢复节目。程序在 1978 开始了并且将为 75 继续 ? 年直到 2050。理解 desertification 和它的驱动力的动力学是为控制 desertification 的一个前提。然而，几乎没有小证据直接与 desertification 过程连接原因的效果(即，在沙的土地的变化区域上)因为 desertification 是一个复杂过程，那能被植被(躲蔽处森林的包括的植被盖子和程度)影响并且浇象 降水那样的因素，表面土壤潮湿，和土壤水分蒸发蒸腾损失总量。这研究的目的是识别怎么影响因素，特别躲蔽处森林，在在一最近的十年的 HSL 的影响 desertification。我们使用了 Landsat TM 形象分析和路径分析在 20002010 期间在水和植被参数里识别时间空间的变化的效果。Desertification 在学习时期期间被控制，以 163.3 的率在荒芜的区域由减少显示了 ? km < 啜 class= “ a-plus-plus ” > 2 ?year ^{在有 desertification 的减少的紧张或程度的区域的 1} 和增加。在 HSL 的全部的植被盖子增加了 10.6 ?% 在减缓 desertification 上在学习时期和这个因素期间施加了最大的直接、间接的效果。到控制 desertification 的全部的植被盖子的贡献与 desertification 的紧张增加了。在稍微并且极其严重的 desertified 区域上，植被盖子贡献了 5 和 42 ? desertification 减小的 % 分别地。在全部的植被盖子和水条件之间有重要关联(即，土壤水分蒸发蒸腾损失总量和降水) 并且躲蔽处森林的区域(P ?

英文摘要：

The Horqin Sandy Land（HSL）, the largest sandy land in the semi-arid agro-pastoral ecotone of Northeast China, has been subject to desertification during the past century. In response, and to control the desertification,government implemented the Three-North Shelter/Protective Forest Program, world＇s largest ecological reforestation/afforestation restoration program. The program began in1978 and will continue for 75 years until 2050. Understanding the dynamics of desertification and its driving forces is a precondition for controlling desertification.However, there is little evidence to directly link causal effects with desertification process（i.e., on the changing area of sandy land） because desertification is a complex process,that can be affected by vegetation（including vegetation cover and extent of shelter forests） and water factors such as precipitation, surface soil moisture, and evapotranspiration.The objectives of this study were to identify how influencing factors, especially shelter forests, affected desertification in HSL over a recent decade. We used Landsat TM imagery analysis and path analysis to identify the effects of spatiotemporal changes in water and vegetation parameters during2000–2010. Desertification was controlled during the study period, as indicated by a decrease in desert area at a rate of163.3 km2year-1and an increase in the area with reduced intensity or extent of desertification. Total vegetation cover in HSL increased by 10.6 % during the study period and this factor exerted the greatest direct and indirect effects on slowing desertification. The contribution of total vegetation cover to controlling desertification increased with the intensity of desertification. On slightly and extremely severe desertified areas, vegetation cover contributed 5 and 42 % of the desertification reduction, respectively. There were significant correlations between total vegetation cover and water conditions（i.e., evapotranspiration and precipitation）and the area of shelter forests（