Abstract:The given eco-geoenvironmental setting has evident control action on land rocky desertification, rocky deserted land mostly distributes in the river-valley regions where karst very developed and tectogenesis was violent in Guizhou province. Warm and humid monsoon climate provides corrosion condition for rocky desertification;Tectogenesis sculptured steep and fragmentized karst land feature with sharp topographic relief, which offer rocky desertification a latent energy;Paleoenvironment supplied rich carbonate for rocky desertification, four carbonate sedimentary formations had developed from late Sinian to late Trias in Guizhou province, pure carbonate rock constitute the substantial foundation of land rocky desertification.

Abstract:Vegetation coverage represents an important role in lessening soil loss, protecting environment and improving the standard of living.USLE, as a convenient model, is applied widely.The studies mainly on method extracting vegetation coverage by using spatial and temporal remote sensing data.As a result of mixing pixels, there is something itself shortcoming for the technique of NDVI monitoring vegetation coverage, and it needs much manpoer and time for field sampling.Linear spectral unmixing is a simpler way reducing workload and improving accuracyof extracting vegetation coverage in remo te sensing image.It need not field sampling and regressive analysis.The value extent of vegetation coverage factor C in USLE model lies between 0 and 1, but the value changed greatly.So the precision of C value is a key to USLE model.

Abstract:Taking＂Two Rivers and Two Stations＂engineering in the Chao Lake catchment as an example,the indicators and fuzzy cluster method for comprehensive environmental impact assessment of large-scale water conservancy engineering are discussed.The engineering effects to regional society,economy and eco-env ironment were analyzed according to the engineering location and characteristics,and to regional environmental background. Based on these, main effect factors were determined through field investigation,analogical analysis,expert consu-ltation and analytic hierarchy process.The compressive environmental impact assessment of the engineering was carried out by using fuzzy cluster analysis.

Abstract:Soil erosion under different elevation was analyzed by using remote sensing and geographical information system technologies.It is shown that the maximum of percentage of water erosion above light and water soil erosion index are 49.2% and 180 respectively, it takes place in the region with the altitude between 1000 and 3500 meters. The maximum of the wind erosion index and soil erosion integrative index are 599 and 367 respectively, takes place in the region with the altitude between 1000 and 3500 meters. The maximum of frozen soil erosion index, 218, in the region with altitude above 5000 meters. The water erosion dominates in the region with altitude under 1000 meters. The Water erosion and wind soil erosion dominate in the region with altitude between 1000 and 3500 meter. The frozen soil erosion dominates in the region with altitude above 3500 meters.

Abstract:There are so many environmental background factors in soil erosion region,such as slope,land use,DEM,etc.However, not all factors play a role in soil erosion equally.Problem about how to identify the main factors in water erosion in China are discussed.Firstly, according to the conditions of study area, environmental background factors that are translated into 100m×100m data format in GRID are choosen.Secondly, degrees for each factor according to the difference degree to soil erosion are set.Each environmental background has different degrees.Thirdly, with the MGE and GIS, we resample in study area in China in equal distance, so that we get lots of samples that can illustrate the study area.Then according to actualsi tuation of each sample, values are put into each sample in line with degrees in the step 2. Finally, all datum are put into software package SPSS for factor analysis.Through factor analysis, the main factors can be choosen.This model is based on expert knowledge and object analysis, overcoming the man-made factor and showing the situation objectively.

Abstract:Based on experiments and comparing analysis, the physicochemical characteristics of crust above the loess soil is discussed mainly, and some results were obtained. Crust formation is a physical process that the framework formed by fine sand and coarse silt is filled by small grain(< 0.01mm). The content of humus is nearly same as that of soil while the content of CaCO₃ is slightly lower. Crust hardness has negative relation with the water content of earlier stage, and has positive relation with bulk density and thickness. The relat ion of bulk density and thickness is more complicated.

Abstract:In order to analyze the influence of land use on soil and water resources,the character of runoff and sediment in different land use should be studied, particularly the relation with rainfall character.The laws of runoff and sediment in different land use varying with rainfall, intensity and erosivity of rainstorm, are pointed out, and their subsection character are laid stress on. Runoff and sediment, and their reduction in different land use all mainly occur in I₃₀≥0. 4 mm/ min,P≥50 mm, as well as their differences. Meantime, runoff and sediment and their reduction in different land use showed a seasonal characteristic.

Abstract:In Hubei province,the soil eroded to inner-city is coupling with formidable soil erosion to backg round in the spatial phase, and they form overlying effect together.Integral structure of soil erosion landscape ecosystem is unbalanced in spatial owing to the differences of the climate, geology, geomorphy in Hubei province.In microscale, the Yangtze river and Jianghan plain are the center of sediment and transporting sand, the currents of soil are assemble successively from north, south to the center section, and from west to east walking through center axes.The spatial structure pattern is unsymmet rical block-ring model.The soil erosion to inner-city is come into being of both social and natural factor.

Abstract:During the process of preliminary designing for soil and water conservation of the Yufeng watershed,Suining city,Sichuan province,ArcView,one software of Geographic Information System, is applied to complete the spatial analysis, to obtain the fundamental data of prelimilary design for soil and water conservation, to map and print required layouts, and to make the system demonst ration.Finally, the relationship between geographic information system and soil and water conservation system is discussed.

Abstract:Delimiting of key zones for soil and water loss control is an important work during soil and water conservation plan.It is different from delimiting of type zones for soil and water conservation with an important directive significat ion for recent conservation. With a case of Guangzhou city, based on comprehensive investigation of soil loss and correlative data, the key zones for soil and water loss control were delimited, including 4 key harness zones,3 key supervised zones and 2 protected zones. The control directions of everyone were also indicated.

Abstract:The macroscopical survey and mapping of soil erosion are generally carried out by many units that use many maps, thus there are some errors of attribute and position of polygons between these units and maps.The seamless joint of map comes true through GIS (Geographic Information System), but GIS can not resolve attribute errors.The procedure, principal and the methods of vector map joint are put forward.For the high work efficiency, three methods based on GIS can be selected according to the size of maps and corresponding images, which are jointed in a single coverage reunited by two coverages, switch in the current and backg round coverages and joint the part/parts split form original map/maps.

Abstract:Selecting a cutting rock slope as test spot at Heng jiang stat ion in Nei-kun railway, the composition ratio of planting material is designed.Else,a test on slope eco-engineering by wet spraying a thick layer material is conducted. The results indicated that effect of slope eco-engineering by spraying a thick layer material is obvious,and that main index of planting material can meet growth of vegetation.

Abstract:The actualities of rocky desertification on sloping field southward in China is summarized,and the reason of it is analyzed.It is mainly due to the vegetation dest ruction, unreasonable cultivation measures, rainstorm and the physiognomy of sloping field according to the analysis of factors on soil lose in Henshan mountains.To prevent the rocky desertification of sloping field, the cultivation measures must be changed, the forest must be protected,and a series of measures of engineering and biochemistry must be taken.

Abstract:Through analyzing the effects of road construction on soil erosion of Jiangsu province,the relationship between soil erosion and road construction is probed into.And several countermeasures to effectively deal with soil erosion from road construction and to protect ecological environment in such an economically developed and impacted area of Jiangsu province are putforward.

Abstract:Based on analyses of the characteristics and causes of soil and water loss in Quanzhou city, Fujiang province, it is clear that the frequent typhoon and rainstorm, and geographical characteristics of mountain and hills, are the strong potential erosive power.The low resistant erosion ability of ground substance, especially the development of granite weathering crust is the inner cause of severe soil and water loss.And the human unreasonable land use, such as vegetation dest ruction, slope land cultivation, cultivation down the slope and the basic economic constructions, is the primary causes of soil and water loss.It is necessary to reconst ruct slope land, and carry out soil and water conservation tillage measures. What is more, comprehensive control in the small watershed as a basic unit is needed in order to control soil and water loss effectively.

Abstract:Water resources is the key factor influencing on western ecological environment.The problems existed in western ecological environment are analyzed.It indicates that these problems are all relating to water resources. The current situation of northwest water resources utilization is analyzed.A scientific way for water resources utilization is raised. Ecological environment construction is a complicated system project, only surmounting difficulty of water resources and scientificaly exploiting and utilizing water resources could ecological environment of northwest China be improved.

Abstract:The problems which restrict the development of Chinese economy are the increasing distance between east and west region, the sharpen contridiction between population and resources, the worse and worse eco-environment,and the insufficient demand.There have a great demand potentiality in west China, and the condition and environment of middle and west region are tending toward ripe.It has great significance of economy and society to develop west China.

Abstract:The situation of global land degradation,its influence on land productivity and threat to food security are comprehensively dealt with. The controlling strategies according to the pattern of land use are proposed.

Abstract:Acid deposition and soil erosion have deteriorated human living environment, w hich has aroused a general concern from people all over the world.The erodibility of acid deposition on soil from the angle of aggregate is studied.Analyzing of the e fects of acid deposition on soil system showed that acid deposition affects soil aggreeation and organo-mineral complex mainly by altering soil acid-based condition,soil colloidal stability and the amount and property of soil cemedins.The influences made soil aggregation decreased,clay content increased and finally soil erodibility enhanced.Obviously, long-time acid deposition plays an important role in soil erosion.

Abstract:The serious soil and water loss and the worsening of ecological environment characteristics in Gansu province are analyzed comprehensively.It showed that the soil and water loss and the worsening of ecological environment are the rest ricting factors of development in Gansu province.The fragile ecology and overloaded population have entailed great pressure on the region.It has been proposed that soil and water conserv ation and ecological construction and protection are the basis and safeguard for sustainable development of the whole area.The combination of ecological construction and economical development is the only way for Gansu province.We have put forward the orientation of ecological construction of Gansu province,that is,(1) to foster the thought of sustainable development ecological construction;(2) to establish eco-agriculture of soil and water conversation pattern and developing small watershed eco-economy;(3) to implement engineering of ecological construction which can make farmers rich.