沙漠化

China has made some progress in understanding and combating the process of aeolian desertification through many years of hard work.

通过对沙漠化发展和逆转过程的研究，特别是基于多年来我国沙漠化治理的成果，文章就防治沙漠化的战略和途径进行了进步的探讨。

The result shows that desertification is serious in the study area. Various types of desertification land add up to 370000hm~2, accounting for 39% of the total land. From l995 to 2000,the serious desertification land, where vegetation cover is below 30%, extends with the speed of 61hm~2 per year. The increasing landscape fragment reflects the intense intervene that human activities act on landscape. Shape index changes indicate the growing ratio of interior -edge, which is disadvantageous to natural recover of land.

结果表明，研究地区沙漠化现象严重，各种类型沙漠化土地总面积37万hm~2占总土地面积的39％；植被盖度小于 30％的较严重的沙漠化土地从1995年到2000年的五年间以61hm~2／年的速度扩展；景观破碎度变大，反映出人类活动对景观的干预作用不断增强；沙漠化景观要素的形状指数变化表现出内、缘比变大，不利于沙漠化土地的自然恢复。

This dissertation focuses on land desertification of the middle reaches of the Tarim River. Taking the train of thought and methods that combining aerial remote sensing and historical material with ground investigation and indoor comprehensive analysis, macroanalysis with micro-analysis, qualitative research with quantitative research, and expressing the result of research by means of mapping, the author makes a systematic research on land desertification.

本文以塔里木河中游地区为研究区域，并以英巴扎地区作为典型区，根据对前人已有成果的学习和吸收，采用航空遥感与地面调查、历史资料与室内综合分析工作相结合，宏观分析与微观分析相结合，定性研究与定量研究相结合，最终以制图手段表现研究结果，并据此进一步综合阐述和探讨研究区域土地沙漠化特征与形成机制以及发展趋势和沙漠化的防治对策的思路方法，对研究区土地沙漠化进行了系统研究。

The preventing and remedying desertification puts into practice prevention as main,principle of combining ecology protection with Prevensing and remedying,principle of preventing and remedy and economy development and utilization coodinated and promoting,comprehensive preventing and remedying and chassified control combines,public particlpation and renovating person benifits combine for different responsibility body bearing different responsibility bearing principle,becanse of man-made fault causing desartification preventing and remedying responsibility carrying out action-person bearing principle,principle of gorernment mainly bearing desertification recovery caused by nature action and benifit's person undertaking reasonable burban and decide unified planing system,systen of desertification status investigation and monitoring early warning system,fallow,limited cultivating hand and help-the poor combined systen,prohibitory systan,priority region and urgent-action region system.

文摘：沙漠化防治实行预防为主，生态保护与防治结合原则，防治与经济开发利用相协调促进原则；综合防治与分类控制相结合；公众参与和整治者受益结合；对不同责任主体实行不同责任承担原则，由人为不当活动造成的沙漠化治理责任，实行行为者负担原则；对自然作用造成的沙漠化治理实行政府负担为主，受益者合理负担原则；确立统一规划制度；沙漠化状况调查评估与监测预警制度，休耕限耕和扶贫结合制度，禁限制度，优先区域与紧急行动区域制度。

At the South Edge of the Tengger Desert, the sampled sites of mobile sanddune, semi-fixed sand-dune and fixed sanddune were selected as the different stages of the reversion process of desertification with the method of substituting time with space, and topsoil mineral elements of the decertified land were studied reversion process of desertification.

以腾格里沙漠南缘沙漠化土地为研究对象，应用时空替代法选择流动沙丘、半固定沙丘、固定沙丘的沙漠化逆转序列样地，研究了沙漠化逆转过程土壤矿质元素的变化特征。

Fortunately, the desertification degree decreased obviously, and moderate and light desertification took the leading position. From 1986 to 2003, the spatial centroid of desertification landscape patches expanded southwestward and northeastward, giving serious threat to the ecological safety of the southeast and northeast loess gully and hilly areas.

沙漠化程度明显下降，沙漠化主导类型已由严重沙漠化转变为中度和轻度沙漠化。1986-2003年沙漠化景观整体上向西南和东北方向扩展，严重威胁着西南和东北部黄土丘陵区的生态安全。

This project was conducted starting with the three interrelated subjects the structural characteristics of desertification landscapes in different bioclimatic zones, desertification driving factors and their function mechanism, and the dynamic model of landscape space for the occurrence and development of desertification in representative desertification regions and on the basis of in-depth studies of the relations between landscape structural characteristics and processes of desertification and their stability; the driving force of different time-space scales of desertification and their proportion, manifestation form, and action mechanism in the desertification processes; and the establishment of threshold conditions for the surface wind erosion and has achieved important progress in the definition of desertification conception

本课题从三个相互联系的专题（即不同生物气候区荒漠化景观的结构特征、荒漠化驱动因素及其作用机理、典型荒漠化地区荒漠化发生与发展的景观空间动力学模型）入手，在深入研究荒漠化景观结构特征与过程的关系及其稳定性，不同时空尺度的荒漠化过程驱动力及其在荒漠化过程中所占比重、表现形式及作用机制，地表风蚀临界条件的确定等内容的基础上，虽未建立荒漠化景观空间动力学模型，但在沙漠化概念，末次间冰期以来沙漠化过程时间序列和特征冷暖时期沙漠、沙地空间分布格局，现代沙漠化过程中自然因素和人文因素的作用、贡献率、沙漠化土地对气候的反馈作用以及风蚀临界值，沙粒跃移轨迹参数和能量分布，我国沙漠化防治思路和对策，沙尘暴区划和沙尘暴指数等方面取得了重要进展。

The historical process of transition between cultivation and pasture animal husbandry and its ecological impact has been analyzed by demonstration to explore the large-scale laws.(2). The driving process has been analyzed and behavior mechanism of local people was also construed.(3) The new interpretation of desertification causes has been made to search root of estrepement, overgrazing and excessive firewood gathering.(4) The comparison and selection have been made to explore new changing direction of integrated land desertification control strategy.

主要进行了：①农、牧业变化的历史轨迹与生态环境演变的实证研究，从大的历史尺度寻求农、牧业变化与沙漠化之间的互动关系；②农、牧业选择变化的驱动过程研究，从较短的时间尺度进行高分辨率的过程跟踪与解析，重点分析农牧民的行为机制；③农、牧业选择变化对沙漠化过程的动因解析研究，重点解析&滥垦、滥牧、滥樵&产生的深层次根源，为沙漠化防治战略的制定提供理论依据；④生态建设策略的比较与转型方向的研究。

In order to explore the grain-size distribution characteristics and geo-genetic types of land desertification in Mo Us desert, the research on the grain-size characteristics of sediments since late Pleistocene has been carried out in the desert area and neighboring area such as inside desert, sand covered loess plateau, loess plateau and river valley. The research result shows that sediments of different geologic genetic types are the fundamental material source of sandy desertification in these areas and the distinguishing of different types of the sediments is the theoretical basis of classification of different geogenetic type of sandy desertification. The contribution of different geological roles on the land desertification and its significance to prevent and deal with the land desertification have also discussed.

为了研究毛乌素沙地沉积物的粒度特征与土地沙漠化的地质成因类型，通过系统研究沙地及相邻地区晚更新世以来在沙地内部、覆沙黄土区、黄土高原和河流谷地与湖泊等不同地质构造地貌条件下所形成的沉积物粒度特征，指出不同地质成因类型的沉积物是这些地区土地沙漠化的物质基础，区分不同类型的沉积物也是构成不同地质成因类型土地沙漠化分类的理论基础，探讨了不同地质作用对土地沙漠化的贡献及其对土地沙漠化防治方面的意义。

Surface-consistent deconvolution using variable prediction step, and suppression of sand dune ringing;2. Spatiotemporal distribution of moisture content in sand dune s of the unirrigated forestation along the southern marginal zone of Gurbantunggut Desert;3. The concepts of sand land, sand dune and desertified land etc.

在实地调查和多年定位研究的基础上，根据目前沙漠化过程研究的需要，介绍了沙地、沙丘、沙漠化土地等相关概念及其主要区别，阐述了沙地、沙丘、沙漠化土地类型的划分标准以及类型互换使用中应该注意的问题；通过分析影响沙漠化发展方向和过程的关键因素，建立了沙漠化正、逆发展过程的地面判别指标体系，并讨论了不同类型沙丘的主要来源、发展方向及转换过程的判别方法。

According to the clear water experiment, aeration performance of the new equipment is good with high total oxygen transfer coefficient and oxygen utilization ratio.

曝气设备的动力效率在叶轮转速为120rpm～150rpm时取得最大值，此时氧利用率和充氧能力也具有较高值。

The environmental stability of that world - including its crushing pressures and icy darkness - means that some of its most famous inhabitants have survived for eons as evolutionary throwbacks, their bodies undergoing little change.

稳定的海底环境─包括能把人压扁的压力和冰冷的黑暗─意谓海底某些最知名的栖居生物已以演化返祖的样态活了万世，形体几无变化。