Abstract:The flood in Guizhou karst depression becomes more and more serious in recent years. The basic principle of karst flood formation wasdiscussed and the reason of aggravating karst flood wasanalyzed from factorsof geology,climate and human activities. Some suggestions were offered for the prevention and cure of karst flood.

Abstract:Soil anti-shearing intensity in water erosion process of the whole country is preliminarily researched in the article by using the firsthand data obtained through field test,indoor analytic data of the physical and chemical propertiesof soil samples and reference data. The regression model of soil anti-shearing intensity is built. The dominate factors impacting on soil anti-shearing intensity in regional water erosion process are soil capacity,ratio of silt to clay,the water content and organic matter content. Soil antishearing intensity regularly changes keeping pace with the soil type,it has obvious space distribution rules in Chinese water erosion region,including horizontal and vertical distribution rules.

Abstract:A due considerations have been paid to the characteristic features and phenomena of the tremendous loess landslides in crows induced by irrigated water. All of them occurred along Heifangtai edges of platform,Gansu province,China. Based on these features and phenomena,such as large extents,high-speed and long traveling distances,their mechanism,kinematical approach and slope stability are analyzed. The regional prevention rules are presented that to take drainage work as the dominant factor and the simple engineering prevention the second one.

Abstract:Based on rock and soil stability theories,the reasonable section shape of water cellar in loess areas was analysed and the theoretical calculation formulasof principal geometry parameters was put forward. It inquiresinto the mechanic characters of loess and the construction techniques,the reasonable pitch of arch of water cellar in typical soil was calculated. These results could work as reference for water cellar standardize construction.

Abstract:Large high-speed landslide may produce a very high increase in temperature,and convert the water in sliding zone into vapour,creating a cushion which sustains the slide mass. As a result,effective normal pressure reduces significantly under the sliding surface,and the sliding mass acquired the high velocity. It was proved by calculation on Touzhai large high-speed rockslide in Yun' nan province that the water in sliding zone can be vaporized,and the value of steam pressure is calculated.

Abstract:In the research of non-point pollution,how to calculate soil erosion modulus is a very important step. With the technical support of GIS,the universal soil loss equation (USLE)was used to calculate the soil erosion modulus of Changshan region in the watershed of Songhua lake. Topography,vegetation and precipitation that influence the soil erosion mould were considered. The relationships among those factors were discussed and some control measures were proposed based on the results.

Abstract:Utilizing the Fuzzy Comprehensive Evaluation Model,a comprehensive evaluation model of the regional groundwater resources carrying capacity is established. And groundwater resources carrying capacity in Guanzhong plain area is analyzed and evaluated by the model. The evaluated resultsshow that this method is reasonable and reliable. Additionally,the related strategies for rational development and utilization of groundwater resources are suggested.

Abstract:The structural and functional characteristics of the under-forest layer of eight main forest types in the hilly area of southern Jiangsu province are studied systematically. T he results showed that differences were existed in amount and function characteristics among the under-forest layer of main forest types.

Abstract:Fengning line of the 112 national road,where the climate belongs to the semi-humid and semiarid zone,the vegetation is lower and soil is porous because of its loess parent textile. This road is 58. 4km in length,and 6 ～ 8 m in width,which will be reconstructed to 12 m. Constructing road affects the loss of soil and water only in some fixed period,and the affecting time is different in different part of soil,such as it is l a in pavements,5a in places where soilswere used to road construction,or places where soils were discarded on the road sides and slopes,3a in temporary occupied places. According to the erosion modulus and areas under different condition,before the road was constructed,the loss of soil and water from road making is784. 0 t/a,and will be 1456. 1t/a during constructing period. So,the loss of soil and water from road making is 708. 1 t/a,which is mainly resulted from discarded soils,roadsides or slopes. The measure is building walls to block the discarded soils,and plant trees and grasses in them or in the road sides and slopes.

Abstract:In order to explore the methods and ways of supervising the construction of soil and water conservation-based eco-environment project,to quicken supervising the construction of soil and water conservation-based ecoenvironment works development towards regularization,standardization and scientism,the system of supervising the construction at Xihe demonstration area of soil and water conservation in the Yellow river valley was carried out. Practices indicated that,it is positive and feasible,and could yield notable results. It improves the engineering quantity,controls the engineering investment and promotes the engineering progress effectively. T he facing problems and countermeasures are proposed about present supervising the construction of soil and water conservation- based eco-environment according to living example analysis and summing-up experience,so as to advance,to perfect and to popularize the system of supervising construction of soil and water conservation-based eco-environment project.

Abstract:Forest tourism is a new property in forest production and it has developed rapidly in recently years. However,with the development of forest tourism,more and more conflicts occur between recreational activities and environmental protection. Forest eco-environment is affected by some factors,which include the forest vegetation and the soil. Under these effects,the diversity and height of plant,the ability of activity and reproduction of vegetation also decline. They may make forest degraded,and the area of uncovered soil increase. Thus,bring about soil and water lose directly or indirectly,and it will be very difficult to regain. Nowadays nature reserves and national parks not only afford protection to natural environment but also provide pleasant recreational resorts. The negative and positive effects are discussed,which are took by forest tourism to the lose of soil and water. So as to explore a good way to give full play to the forest function.

Abstract:Vegetable,wheat,cotton and melonscrops were tested with the underground film technique. The result shows that under the traditional planting measures,the yield of vegetable with underground film increased by 64. 9 %compared with the contrasting field,wheat 65. 0%,melons crops 79. 0%,and the increment of water use efficiency is 106. 2 %,56. 3 %and 162. 1 %separately. So the underground film technique is one of the new agricultural techniques,which could increase the yield,water-saving and fertilizersaving.

Abstract:A field experiment was conducted to study the spatial variability and scale dependence of soil hydraulic properties. Infiltrometers with three disc diameters (14. 4,20,and 30 cm)and 2 tensions(1 and 10 cm)were used to measure infiltration at 65 locations. With the infiltration data,hydraulic conductivity and macroscopic capillary length were calculated. The frequency distribution of hydraulic conductivity and macroscopic capillary length was log-normal. The spatial continuity of soil hydraulic conductivity and macroscopic capillary length was better displayed by measurements with large disc sizes. When tension was 1cm and disc diameter was 14. 4 cm,the spatial structure of hydraulic conductivity was not displayed. The mean of hydraulic conductivity and macroscopic capillary length tended to decrease as measurement scale (disc sizes)increased. The values of nuggets and sills of the sample variograms of hydraulic conductivity and macroscopic capillary length decreased as measurement scale increased.

Abstract:Guizhou is a province of Karst development,it is affected by mankind action especially,and it isn' t unreasonable to using of land resource,flood disaster take place frequently. It lead to a series of environment problem. So people in karst region,if land desertification isserious,they are very poor. It enhances request of soil erosion work and building of ecological environment in karst region. The grade of land desertification is investigated and its space changeable,affecting parameters,causes and degree are analysed by GIS and remote sensing techniqu in Guizhou province,the map of land desertification in Guizhou karst region are made. Meantime,it is a completing way of science and technology,it is going to provide dependable data for soil erosion preventing and ecological environment managing.

Abstract:The laws of forming flood on sloping fields and soil and water losswere researched by experiment in laboratory and field. According to the condition,Deferent models of preventing flood in centric experimental area are established. The benefit of the models are observed,and a perfect technical system of preventing flood in low mountainous gneiss region is established.

Abstract:分析了田间同深度土壤含水量的半方差和不同深度土壤含水量的交互半方差特征，探讨了土壤含水量的Kriging和Cokriging估值方法。研究表明，同深度土壤含水量与不同深度的土壤含水量之间均具有显着的空间相关性，用Kriging方法进行土壤含水量的估值精度较传统方法高。加入浅层土壤含水量用Cokriging方法来估测深层土壤含水量，可进一步提高估值精度。

Abstract:Agricultural sustainable development is a very important strategic task in the development of arid and sem-i arid region in Northwest China. The successful practice of the deserticultural theory has proved thoroughly that it is prospective,realizable,and is especially meaningful in the agricultural sustainable development of arid and sem-i arid region. The deserticultural comprehensive benefit and achievement in the agricultural development of arid and sem-i arid region are analysed based on deserticultural theory and sample of deserticultural construction in north and central of Ningxia Hui Autonomous Region. Deserticulture is a sustainable agriculture and eco-agriculture in arid and sem-i arid region of Northwest China.

Abstract:The comprehensive control of the Tiewa small watershed project in Xichan country has been carried out for 3 years (from 1994 to 1996). Its total investment was 2 million and 88 thousand yuan. The project prevented and cured 12. 51km²area of the soil and water loss. The control degree of soil and water loss in the control areas reached 91 percent. The utility of land increased from 32 percent to 91 percent. The covering degree of plants increased to 82. 5 percent from 22. 9 percent. The production force for the land increased to 3 750 yuan/hm²from 1750 yuan/hm². The income of each person increased to 1 710 yuan from 680 yuan per year. The project has shown its obvious economic,ecological and social benefits.

Abstract:Flood and drought alternate frequently in hillocky area of the Four-river valley in Hu' nan province because of the soil and water loss for many years. The interweaving situation of outside flood and inside waterlogging is getting more and more seriousin Dong-ting lake plain. Though soil and water conservation eco-environment construction has gained certain achievements for the last several years,the speed of the construction is still restricted. The causes are that they lacks funds,the strength of enforcing the law is small,the content of science and technology is less. The guarantee mechanism of soil water conservation eco-environment of the whole province is brought up. That is to set up and perfect the funds channel,to support with science and technology to supervise enforcing the law,to manage and to build it altogether. Strengthen the construction power so as to realize the near-term,mid-term and long-term objectives of soil and water conservation eco-environment construction in Hu' nan province.

Abstract:Forest vegetation can ameliorate obviously eco-environment,prevent land deterioration,improve the content of soil organic matter and available N,K,and drop soil pH and bulk density,add remarkably the quantity of water aggregate( > 0. 25mm) and micro-aggregate( > 50Lm) of soil,which can make soil construction better,improve the capacity of providing nutrient and water,enhance the formation of clay and more solidity,increase soil ant-i erodibility and ant-i scourability and decrease effectively soil and water loss. Vegetation fertilized and ameliorated soil mechanism is a right direction of abiding feedback,long time and more benefits.