Abstract:From the macroscopic decision it is advanced that developing "tworinged belts" and to renovate "two regions" should be the general concep-tion for agricultural construction and comprehensive dredging and explo-ration of the loess plateau. The two circles distribute on plain, basinand adjacent mountain of the area, the inner circles is a golden range,mainly producing commercial grain, the outer one is a green one withthe construction of shelter-forest. The two regions are hill and sandarea in central part of the area, the southeast part is for farming andbreeding taking soil and water conservation as the major work, and thenorthwest for breeding taking control of sand and wind harm as stress.The conception would help the country to map out policy and strategyand to investing for the dredge and exploration of the loess plateau.

Abstract:The small watershed harness undertaken by household are at stablenumber, being without great fluctuation, and that the benefit more thaninput, which enhances peasants in mountainous region to take off poor-ness and get rich.The households undertaking the harness are transittingfrom harness-type to the ecnomy-type through the construction of capitalfarmland, orchard, grass planting and animal raising, and the building ofcommercial forest, etc. .The province accepted the combined ways of var-ious types,including establishment of special team in soil and water con-servation to uphold harness year in year out, harness being concentratedor in stretch using accumulated labours according to unified plan of com-mune or village,partial recover of soil and water conservation investmentby building commercial economic land through establishment of co-opera-tive body with the share of source, foundation, manpower and techno-logy, setting of land development company to manage land in market ma-chanism and change manage station of water conservancy and soil conser-vation into economic entities. Only if could these types be complementedeach other, better results may be obtained.

Abstract:Ailinghe is one of the poor communes in Weichang County. From theyear of 1984 on, masses there set off great upsurge to develop mountain-ous region through soil harness and foundation solidification, soil enri-hing to produce property, water transforming and benefit promotion.In five years 47 branch ditches and 1,319 hair ditches have been harnessed,more than 3,800 hectares of mountainous area have been tackled, makingamount to 63.3% of the total area, which strides the first step to elimi-nate poor root and from which a magnificent prospect of new villagewith rich peasants and picturesque scenery is initially realized.

Abstract:The focal points of soil loss harness in the country, including threegreat stretches,i.e.,the middle and lower reaches of Jialin River, the reser-voir area of the, Three-Gorge, and the lower reaches of the Jinsha River,are located in Sichuan province.It is suggested to take the advantage ofthe harness time to take the lead in exploiting the resources of water ener-gy, minerals, agriculture and forestry and tourist,which is not only re-lated to the economic promotion of Sichuan and the upper reaches of theYangtze River, but also to the fundamental interest of the middle and lowerTeaches as well as other provinces along the river.Three points are raisedto give high notice and to impliment urgently, one being to work on theprinciple of systimatic engineering, the second to change the way of"running electricity by one side", and the third,to carry out the policy of"self-support of electricity".

Abstract:The region governed by Sichuan Province at lower reaches of Jing-shajiang River is mostly lived in by national minority, being a poor andbackward place. According to local geographical condition, soil and waterloss level and the current state of agricultural development as well as itsdeveloping trend it is divided into dry and hot valley area, middle moun-tain, hills, high and middle mountain and mountainous area.It is raisedto work out combrehensive measures to control, to suit measures to localconditions, to develop rationally and to protect actively, to combine soiland water conservation with the development of commercial economy inorder to enhance virtuous ecological circle.

Abstract:The longitudinal and transverse vally gadient in Xingzhihe water-shed was measured, it decreases progressively from upper to lower rea-ches.There is a componet function relation between transverse valleygradient (first order branches) and valley length. In this watershed thepopulation density,precipitation and temperature increase by degrees butsoil erosion intensity decreases with decreasing of altitude. According tofour factors above,the authors have suggested macroscopic control patternthrough longitudinal, transverse and vertical zones in whole Xingzhihewatershed,so the Xingzhihe watershed is divided into three zories: Aero-sowing herbs and shrubs zone; mixed zone of forest, shrubbery, pastureand agriculture; agriculture zone with basic farmlands.

Abstract:On the basis of data obtained from field investigation and the meas-urement of topographical map, the present paper dealt with the originof soil erosion in a certain small watershed in Chunhua Model County.The relations among soil erosion and erosion causes are shown by the for-mula E= f(J·ρ·C·S). It was found by relation analysis among erosive mo-dulus and erosion causes that topographic grade, channel frequency, thenumbers of active gully head, the vegetation coverity of slope, and thesize of watershed area had close relations to erosive modulus. However,the forest coverage and the level of Yuanmian control did not have closerelation to erosive modulus. It was considered that those results werecaused by few measurements, low level, poor quality, nonorganizationsystem of soil and water conservation practices nowadays in the area.

Abstract:Through wide field inventory, remote sensed image and topographicmap analysis, we found landslide groups and obtained the moving direction data of 162 landslides in southern Ansai county of Shaanxi Province.The moving directions of landslides have the preferential orientationsNNE-SSW and EW. In order to find a possible connection of landslideswith neotectonic stress field conditions, the 926 valley orientations havebeen measured on 1:100,000 scale topographic map. The preferential valleyorientations are N8°E and N77°E. Accordingly, they are considered asthe two shear directions of the local neotectonic stress field. Thus, oneof the principal stress directions has an orientation near N43°E, theother near S133°E, the first of these azimuths corresponding to the maxi-mum compression. Two of the shears can be compared with the movingdirections of landslides.

Abstract:Caragana microphglla is a stable shrub species for afforestation in thesemiarid loess hilly region. Its root system belongs to the tillering ca-tegory of taproot type and is relatively developed. The biennial-tetren-nial plant root system ranges from 1.5 to 4.0m deep and from 1.0 to 3.0wide. Most of the roots are distributed in the depth of less than 50cmsoil layer, and the distribution form changes gradually from column tocone-shaped as time goes on. The root system of C. microphylla has quite good plasticity and dif-fers evidently in growth under different locality that depends mainly onsoil structure, fertility and moisture. The way and quality of soil pre-paration exerts great influence on the growth of root system. There is certain correlation in growth between root system and thepart on ground of the plant. The length of biennial-tetrennial plant rootis about 5-6 times of plant height. The weight ratio of C. microphyllaroots to the part on the ground decreases with the increases of its age.

Abstract:Based on evaporation from water surface (the emended E601's evapo-ration) in Changwu tableland, the revised Penman's formula is tested inthis paper after having briefly been introduced, and the result is relati-vely satisfactory. Besides, the cause of the deviation, the influence of itat abvection and the computation of potential evapotranspiration are dis-cussed in the paper.

Abstract:The debris flow should be managed with the principle that takesprevention as the major point and combines with renovation as otherengineering disaster is done. To ensure the development of mountainoustown and industry as well as the safty of railway, road and shipping,on performing the study of distribution mechanism, causes and nature ofdebris flow, it is suggested that while conducting engineering renovation(hard control) the study on soft control be paid special attention,that is,to research forecasting and warning system to inspect, to establish thewarning and disaster prevention system suitable to this department ordistrict, to set up laws and regulation, to bring the power of flood preven-tion branch into full play, social organization and individual person in or-der to keep the debris flow harm within limit and decrease the disasterloss to the least level through various kind of propagating intermediumand population of disaster prevention practices.