Abstract:The water problems of the Liaohe river catchment were discussed systematically. Based on the evolution of precipitation and run off，the probability of drying-up was derived from the picking-up of erosion,pollution,waterlog and droughts. At the same time,the countermeasures and proposes for the sustainable utilization of water resources in the catchment were pointed out.

Abstract:According to the classification system and methods in“Ramsar Convention”，“Investigation 0utline of Wetlands in China”and other classification systems,the wetlands in Yellow river deltais classified by three times,and their distribution,areas and major character；are outlined respectively. The complexity and diversity of wetland types and eco-environment in Yellow river delta created rich wetland resources,including biological resources,land resources,shell sand resources and sea resources. However,owing to man's unreasonable utilization,eco-environment in Yellow river delta are getting worse gradually，some wetland resources are degenerating or even lost,so it is imperative that wetlands are conserved and utilized reasonably. The countermeasures of sustainable utilization of wetland resources in Yellow river delta are put forward.

Abstract:The year from March till May in 2000,the northern in China take placed 13 times sand-dust storm. It makes everyone feared,be recognized the environment become worsen in Beijing and around area,Sand-dust storm is present soil erosion,serious soil erosion,the serious consequence of the vegetation being destroyed,and serious zoology disaster as liked coast,landslid and debris flow.Zhangjiakou and Chengde areais main sand-place.To control the place of soil erosion,is unimportant thing to keep the sustable development.

Abstract:As a particular mechanism of land salinization, freeze-thaw action is differing from salification process by violent evaporation, it has distinct control action on springtime salification, but it has not been much accounted adequately. In the process of feezing and thawing,soil profile constitution is divided into three layers frozen layer, semi-frozen layer and unfrozen layer, special travel of water and salt was made.In the process of soil freezing, soil water and salt move towards fozen layer from the underlayers,salinity in the frozen layer increased evidently. In the process of soil thawing, the salinity of frozen ayer assembles in the upper soil layer along with violent vaporizing in springtime. Its intensity level of salification like“eruption”this time, the land salinization has no relation with ground water table, because frozen layer by way of waterproof layer insulate unconfined water. So it is unauthentic that the critical depth of unconfined water controlled that“eruption”salification in springtime.

Abstract:Used the method of water-balance, the redistribution of rainfall by mixed forest in Huoditang area of Qinling mountain is studied. The results are as follows (1)Woods canopy 's interception of rainfall,runoff of woods stems and the rainfall under the woods are 126. 58, 11.69 and 588.2mm，which account for 17. 43, 11. 61 and 80. 96 percent of the total rainfall respectively during July to October in experimental area.Most of precipitation falls into forest by the rainfall under woods.(2)Dead leaves and branches under the woods intercept 85. 01mm rainfall, which account for 11. 75 percent of the total rainfall. They play important roles in retaining water.(3) Changing amplitude of water storage in woodland is 53.45mm. Woodland is very important for reducing the crest of runoff, adjusting runoff and shortening dry season.(4) The results of forest eco-system water-balance are that forest evapotranspiration is 521.01mm, the runoff is 155.24 mm，and the change of woodland soil water storage is+50. 09 mm. They make up 71.73, 21.37 and 6.9 percent of the total rainfall, 726. 34mm of the same period. Forest evaportranspiration is the most part of woods water output.

Abstract:Guizhou is a province of karst developing very avidly and intensely, soil erosion intensity and dangerousness of potentiality are very strong.Recently，the present condition of soil erosion is speeding up, and flood disaster takes place frequently, it enhances the request of soil and water conservation work.The authorn investigated soil erosion and analyzed its spatial changeable by GIS and remote sensing technique in Guizhou province.Meantime,completing way of science and technology，it is going to provide dependable data for soil erosion preventing and ecological environment managing.

Abstract:Through analyzing the development of ecological and economic system of agriculture and 3 different constructing models of ecological agriculture,the basic developing thinging for ecological and economic system is pointed out.

Abstract:It has been known from studying on 37 forest types that the water storing level of forest in Hunan province is very low .The average total quantity of water storing is 4102.9 t/hm²,and the effective quantity of it is 830.2t/hm²; The largest effective quantity of water storing in natural forest,artificial forest and ecological forest of simulating natural reaches 1049.7 t/hm²,534.5t/hm² and 764.0 t/hm² respectively. The largest effective quantity of water storing of natural forest,middle-age forest and young growth forest of natural forest reaches 1285.1/hm²,1065.4/ hm²and 798. 5 t/hm² respectively;The 3 ages classifacation of artificial forest are 642.5t/hm²,563.0 t/hm² and 534.5 t/hm². The techniques for water preserving capability improving in forest land were advanced acxeording the low quality and its low function of water storing.

Abstract:In accordance with climates condition for planting different fruit trees.The climates condition of plain,sloping and different slope direction,slope site,the suitablefields in loess hilly-gully region of northern Shaanxi province are put forward. After analyzing the humidity of orchard soil in the area, the water-saved irrigation way and irrigation quantity are put forward.

Abstract:By using a dynamic experimental devices of debris flow，a series of indoor model tests on debris flow passing through drainage canal arc carried out. The shape of cross-section of modddrainage canal is rectangled with a width of 25 cm. The solid material is take from the Jiangjia ravine of which the gravel's maximum diameteris 40 mm. The test results are as follows:(1)Debris flow of the maximum diameter of<0.05mm can move on very small gradient of drainage canal;(2) The larger density of debris flow，the larger gradient of drainage is;(3) The gradient of moving debris flows in the drainge are relation with the density of debris flow，gravel s maximum diameter and fine particles.

Abstract:The steep sloped}and of purple hilly area of Sichuan basin account for 15% of total area.In order to utilize the steep sloped-land completely and rationally,the following designed approaches for soil and water conservation of sloped}and were investigated cover straw(CS),collect water with pond and pits(CW-PP),plant straw}locks along contour(PSB) and plant rye}rass(PR G).The results shown that all this practices bear a certain efficacy as expected.Among this alternatives,PRG ranked first in increasing soil water content for the research conditions,and PSB,CS ranked second. From the aspect of preserving the stability of soil moisture, the desired results appeared in CS and CWPP,from which some rainfall-intercepted was discharged during a few days after raining.

Abstract:The rapid survey and assessment study on region-scaled soil and water loss is very sigificant macro-decision-making of regional soil loss control,quick control to natural disasters and construction poster-regime on soil loss regularly.Based and on the study of region-scaled soil loss and 3S application,the rapid assessing method is put forward and taking the whole loess plateau of China as a sample region,series of indices are defined; the model is set up to help to appraise the soil loss in this region; finally，soil loss of the loess plateau is assessed using the model,and some fine results have been got.

Abstract:The radio telecontrol monitoring warning system aims at the geological hazards in mountainous areas.By the moitoring on the dangerous rockmass and the gliding mass,we can get the new development data about the mass. Rased on the analysis of the data, the stability of the dangerous rockmass and the gliding mass can he assessed.The landslide forecast or the warning information slumping.Gu angiiaya The application of this system gives service to the prevention of natural adversities.The study at Guangiiaya dangerous rockmass in the three gorges of the Changjiang river,is a example how to seize the warning signs of slumping and to reduce the loss caused by landslip to a minimum.

Abstract:The preliminary experiences and lessons for application of contour hedgerow technique in Ningnan county of Sichuan province are presented.As an effective technique for soil erosion control and fertility improvement proved by on-site research and demonstration, contour hedgerow intercropping has been widely adopted by local officers and farmers.In order to improve environment quality and protect slope cropland,many measures will be taken for further promoting the technology extension in the coming years by Ningnan county government.

Abstract:The practical measures used in the comprehensive treatment for soil and water conservation of small watershed are introduced. The benefits comprehensive treatment for produced by treatment,which can be the same kind of small watershed in soil and water comprehensive treatment are analyzed .

Abstract:Through overall discussing the effect of forest management practices such as harvesting, site preparing, soil preparing, tending and agroforestry managing, it indicated that any forest management praotire influencing on land covering and soil properties can increase soil erosion.Further the more the management practice disturbed the forest land, the more soil erosion was, this is especially obvious on the area that erosion durability of soil was low and rainfall erosivity high. Improper cut and site preparation may increase soil erosion; If site preparing,tending,agroforestry management were inappropriately employed, erosion may increase sharply，young stand soil thus may directly affect the long-term maintenance of stand fertility.In order to attain soil and water conservation and maintenance of stand long-term productivity, the overall study on effect of traditional forest management practices on forest ecosystem should be strengthen and the disturbance intensity of management practices on stand be decreased to the full.