Abstract:Most of the petroleum delivering pipe-line jetties running across wilderness are bare or grassless. In annual rainy season,precipitation washes heavily away pipe-line jetties' soil. It is one of the principle problemsof the normal operation. By lots of indoor and outside experiments,the formation of the bare pipe-line jetties and the mechanism of soil erosion are analyzed. Then a vegetation regeneration method for the light-mediated alkalized pipe-line jetties is put forward,and the feasibility of applying cement soil lining to the serious bare alkalized pipeline jetties is analyzed. The cost of construction is less than 1/5 of cement-rubble lining,so a new preventive measure is provided for the alkalized pipe-line jetties.

Abstract:Based on the measured data and the model of plotted watershed hydrology,the benefits of water reduction by different harnesses of soil and water conservation are firstly separated in watershed scale,which are the basis of evaluating the effect of rebuilding ecological environment of the loess plateau on the water resources of the Yellow river. The results indicate that the benefit of watershed water reduction by engineering harness of soil and water conservation was 18. 1%on what had been achieved in the period of the sixth five-year plan,and that the benefit by ecological and agricultural harnessof soil and water conservation was 10.9 %on what had been achieved in the period of the seventh five-year plan. For reducing the effect of ecological and environmental construction in the loess plateau on water resources of the Yellow river,the ecological and agricultural harnesses should be main measurements.

Abstract:Using the 10 year observed data of runoff and sediment in the loess hilly forest region and the field antiscourability tests,the anti-scourability in the forest-land and the reclaimed lands were analyzed. The results showed that the forest-land had the strong anti-scourability. After reclaimed,the anti-scourability of reclaimed lands had the decrease tendency from 4.01g/L to 25.51g/L in the flow of 3 L/min,which would increase the soil erosion intensity. Correlation analyses found that the soil shear strength had the biggest effect on soil anti-scourability,and then,the water stable aggregate and the organic content. So it could control effectively soil erosion to return reclaimed lands into forest or grass land,and recover or reconstruct vegetation.

Abstract:With the experimental data,the processes and dynamicsof the water,soil and nutrient losses and the effect of the treatments of cultivation and rotation systems were analyzed in hilly red soil regions. T he comprehensively harnessing techniques for eroded red soils were proposed. T he area of land subjected to soil erosion was 21. 5% of the total. The interannual variations of the water loss and soil erosion were largely up to eighteen to twenty-fold,its seasonal changes were mainly influenced by rainfall distribution,vegetation cover and human activity. The application of protected cultivation measures decreased obviously the loss of water,soil and nutrient. The development of the comprehensively harnessing techniques and the establishment of the suitable water and nutrient conditions were the effective measures for the quick rehabilitation of vegetation and soil fertility in eroded soil regions.

Abstract:Tangnaihe hydro-station is one of major controlling station of the Yellow river in Qinghai province. The average annual runoff through the hydro-station is 2. 0×10¹⁰m³,with 34. 5 %of the annual runoff 5. 8×10¹⁰m³ of Yellow river and 91. 0%of the runoff in the main aspect among the Qinghai province. The place beyond Tangnaihe is one of the major water supply and conserving area for the Yellow river. Through analyzing statical character of runoff and sediment across the station from 1919 to 1999,the years that low and partial low flow year appeared frequently were in the 1920' s and 1990' s,and the years that high and partial high flow year appeared frequently were in the 1940' s,1960' s and 1980' s. Changes of annual sediment mainly depended on annual runoff,they changed synchronously and were significantly related with each other. The decrease of runoff and sediment on the mainstream of the Yellow river in 1980' s was mainly due to periodic changes of annual runoff. And 1990' s belong to a partial high flow period. Compared with low and high flow degrees in history,the partial low flow period in 1990' s is normal. Changes of annual runoff on the Yellow river in Qinghai province have not developed towards decline,and changes of runoff and sediment were stable.

Abstract:The effects of soil erosion control and soil improvement were researched through the observation of runoff and soil erosion,and through the analysis of some indexes of soil property in the plots of three kinds of artificial forest,Pinusyunnanesis community,Eucalyptus maidensii and mixed Acacia mearsii -Eucalyptus maidensii community and the non-forest contrast from March 1,1998 to March 1,1999. The results indicated that mixed E. maidensii -A. mersii community,P. yunnanensis were able to efficiently control surface runoff and soil erosion and there were high percentages of Si/V,stable-water aggregate,non-capillary porosity in the soil of these two artificial forests. Meanwhile,less loss of main nutrient elements happened,which was in favor of the fertility better improved and more organic matter,available N,P,K were accumulated in soil of mixed E. maidensii -A. mearsii community and P. yunnanensis community. To the contrary,both the soil erosion control and the improvement of soil were poor for the contrast and E. maidensii community. So,mixed E. maidensii -A. meamsu communities,P. yunnanensis community should be recommended for afforestation in the harnessof soil and water erosion.

Abstract:The transporting characteristics of debris flow of different types (viscous,diluent and water-stoneat Guxiang accumulation fan in the Tibet Autonomous region are studied by indoor model tests. The reseach focuses on the transportation of debris flow,the erosion and deposition of debris flow fan,the changesof sediment concen- tration. The results show that they are controlled by the characteristics of debris flow body and the longtudinal slope of accumulation fan.

Abstract:Erosive rainfall standard,which can pick out erosive rainfall from all rainfall events,has to be determined based on the rainfall samples. How the sample size influences the erosive rainfall standard has not been reported yet. According to the rainfall and runoff data during 1962-1969 attained from Zizhou experiment station in the Yellow river basin,the effects of sample size on the valuesof erosive rainfall standards were studied. To get the stable rainfall standard,large sampleswere needed. But considering the data available and not too much work,5- year data were enough for determining the erosive rainfall standard.

Abstract:Taking Jiuyuan valley in the loess hill and gully area as a test site,the accuracy of terrain variables derived from 1∶50000 scaled DEMs by means of a careful comparison with high accuracy DEMsof 1∶10000 scaled is probed into. The experiment shows a big error between the terrain variables(i. e. slope gradient,surface curvature,channel networks etc. derived from the both information sources. At present,1∶50 000 scaled DEM has been set up in the whole country,which will be applied as an important base for soil erosion investigation as well as soil and water conservation project planning in the loess plateau region.

Abstract:The notion of landscape of soil erosion is brought forward for the first time. The meansof expression on types of soil erosion and grading of intension is the paper medium long-term in soil erosion scopes. Quantitative study aims at the aspects of soil erosion mechanism and erosion quantity of small catchment or sidehill before. In the course of possession of the digital information on soil erosion figures,the integration of RS and GIS technique is used based on ARC/ INFO. The texture of soil erosion landscape is figured out by the digital information of patterning. The method of the regional location quotient is quoted,which is one of the typical methods on urban economical basic theory. The missdistance of soil erosion between one of soil zoology region with the other region can be assessed. Based on three facts discussing before,the patterning information is analyzed,and landscape diversity and the regional location quotient are calculated. The results show that there are different valuesin different soil ecology region in Hubei province. The method provided the train of new thought for quantitative study in erosion soil scopes,and it makes great sense for valuation in separated soil erosion area of Hubei province.

Abstract:The main factors affecting the soil erosion are analyzed synthetically,Which includes meteorology,to-pography,soil,rainfall and human activity. Combined the data gained and the result researched,the grades of soil anti-scourablity,erode force of rainfall and relief of topography are confirmed as the indexes of China potential soil and water loss based on GIS,which could be applied on macro assessment of China soil and water loss.

Abstract:Based on the investigation of current status of the cellar construction project for water harvesting in loess plateau of china. It is pointed out that the existed problem in the project,which included of superfluous of cellars along the supperways and roadways,shortage of ground for water producing,and also problems in cellar construction and sand sinking pound. According to the analysis of potential water harvested and water needed for human and livestock and irrigation,a system of cellar quota is given for the along road cellar construction. And also,some countermeasures to well build the cellar water harvesting system and better sand sinking pound are recommended.

Abstract:A long-term experiments was carried out in Tanguanyao and Masangping site in dry valley of Jinsha river with a climate of more than 90%of its rainfall in monsoon from May to Oct since 1991. The long-term experiments involved five treatments with three replicates(CK:control,conventional slope tillage,T2 and T3 :Leucaena leucocephala hedgerow with or without fertiliszr|T4 :Tephrosia candida hedgerow with fertilizer,and T5 : mulberry trees within Leucaena hedgerows with fertiliszr. The pruning of contour hedgerow of Leucaena and Tephrosia were used as mulch. The crops were the same in the same site. The results showed that contour hedgerow intercropping could reduce runoff of sloping cropland significantly. Compared with the control,contour hedgerow intercropping decreased runoff by 26 %～ 60%. Regression analysis showed that linear dependence exists between events runoff under contour hedgerow and that of CK. The data of events runoff indicated that surface flow of sloping cropland mainly occurred in the metaphase and anaphase of monsoon.

Abstract:The phenomenon of wind erosion and desertification is widespread in mountain area of Hebei province,and it plays an important role in sand-dust storm in 2000. The reason of wind erosion and desertification in Hebei province is analyzed,one is drought,the another is human absurd produce activity that make the vegetation destroyed and land desertification. In order to control wind erosion,5 measures are brought out that to increase artificial rainfall,to develop irrigated farming and to rise using rate of water resource,to control soil erosion,to optimize the frame of crops and solid expoiting,and to establish control and forecast system.

Abstract:Ginseng is suitable to growing at deep layer and fertile soil. To plant ginseng,people generally adopt allcuting forestland and clearing away root stubble and longitudinal slope to made bed. From cultivation to harvest,it need change bed once in six years. After planting,ginseng land could not be used for 30～ 40 years,it causes serious soil and water loss. At soil prepared and basked,the land lose the protection of vegetation|At management period,there have 20～ 25 percent ginseng land area' s production way bear all ginseng land' s rainfall |discard land after plant ginseng,soil texture is porousand surface soil isuncovered. In the three different stage,appropriate soil and water conservation measures are taken to prevent and control soil and water loss.

Abstract:Anxi county isone of the seven main county with serioussoil and water lossin Fujian province. The area of soil and water loss is wide and the degree is acute. Based on analysis of the history and present situation of soil and water lossin Anxi county,the formation and developing trend of soil and water loss isanalyzed by the numbers and several integrative countermeasures of prevention and cure are put forward.

Abstract:Based on the procedure and technological process of the national survey with remote sensing and geographic information system(RS and GISof soil erosion,the system of quality assurance and quality control is put forward,which is named as which managing whole technological process,taking practices of quality control in every link”. The system included three steps,which are the technological training before the survey,quality control during the investigation of provinces,and checking and accepting the works of provinces and integration of digital maps of whole country. Every step included necessary links and measures. The practice proved that the system was effective which could meet the demands of the national survey of soil erosion.

Abstract:The quantity,quality status,and temporal and spatial change of water resources of Haihe river basin are analyzed. Combining with the analysis on water resources changes and causes of Huaihe river basin in history,the impact factors on sustainable use of water resources are explored. The water resources change is the interaction result of multiple factors,such as natural,social,and economic factors. To realize sustainable use of water resources of Huaihe river basin,people should apply systematic harness and management method. From the sustainable use of water resources and the practical status of Huaihe river basin,some countermeasures are proposed.

Abstract:It is thought that serious soil erosion of Huangshan city is resulted by natural and social environment : the former including broad distribution of granite and much precipitation,the latter including fault of macrodecision,deviation of value choosing,and sharpen of man -land contradiction. Therefor,in order to restore and reconstruct agriculture ecological environment of the mountain area,people in the district must intensify consciousness of preserving agriculture ecological environment,adjust industrial structure,improve mode of production,and carry out soil and water conservation measures.

Abstract:By visiting the peasant households,the main participator the behavior of peasant on soil and water conservation in the gully area of the losses plateau is studied. It is found that there is a big difference between peasant and the government of their goals in soil and water conservation,the peasant use soil and water conservation measures to maximize their income,but the government. s purpose is to improve the environment in this area and let the Yellow river and its drainage area be safety. Finally,some policy countermeasures proposes to harmonize their goals and encourage the peasant to take soil and water conservation measures.