Abstract:The effect of human reclamation on modern erosion was puantitively analyzed by study on relationship between human reclamation and evalution process of sloping surface. It was estimated that in loess hilly and gully region, the slope erosion might be increased about 25% by reclamation and cultivation.

Abstract:This paper studies mainly soilanti-erodibility indices of mixture-planted and pure-planted forest. Results show that soil organic material and water stable aggregate contents of mixed forest are greater than those of pure forest by 38% and 23% respectively, rate and coefficient of soil dispectively in 0-100 cm soil layers under the same condition. The difference of organic material and water stable aggregate contents between mixed and pure forest-land is extremely significant. The difference of rate and coefficient of dispersion between mixed and pure forest-land is significant, but the indices of various sooil layers is irregular.

Abstract:From the small watershed data since libration and materials in experimental runoff plots under different controlling measures in early 1970's as well as precipitation, the connotative relationship between precipitation and soil and water loss was found by frequency and mathmatical statistics and analysis. The result showed that the soil and water loss in small watershed could be estimated by precipitation regression equation, and in experimental plot by experimential model with main component method, which provided a scientific basis for soil erosion and loss research as well as small watershed comprehensive control.

Abstract:The soil and water conservation division of Shandong province was discussed in this paper. Based on the nature and social conditions. The factors which affect soil erosion and water loss and erosion situation, the principle of soil and water conservation division in Shandong province was proposed under the premise of water conservancy ministry for unified division of fiest and second grade. According to this principle, whole province was divided into third grades and 12 subgades.

Abstract:The present situation investigation of soil and loss and 1985-2000 soil and water conservation planning had been carried out from 1984 to 1987 in Jiangxi province. The economic benefit of the plan was analyzed by dynamic method. The result showed that the benefit-cost ratio was 4.79 and the investment returning period was 2,41 with internal return ratio of 22.48%. This reasonable plan should be carried out as quickly as possible to obtain the benefit.

Abstract:The development of soil and water conservation of Anhui province were reviewed in this paper. Based on the reason why the work rose and fell and summrized the experience, the author pointed out that the soil conservation, which was not a pure technique problem but a economic and social one, should be foused on "Law system" perfection so that the significant benefit could be gained.

Abstract:There was a catestrophic flood in Yeerqiang river of Xinjiang in Aug.30,1984, which lost about 500000 yuan on damage water conservancy projects along the river and cost 300000 yuan for rush repairing. Since 1949, there had been carried out in th source of the river by a united team of department of water conservancy of Xinjiang and Institute of Glaciology and Geocryology, Academia Sinica etc. It was found that the flood, coming from the modern glacier area of the source, was caused by breaking of ice-dam and coffer-dam lakes formed by blocking of river with glacier movement.

Abstract:The situation, damage, develping trend and reason of erosion are analyzed by investigation in this paper. The number of counties and cities with soil erosion in the province has increased from 34 to 87 since 1950's and sediment transported to Dongting Lake raised by 34.2%. The total siltation in the Lake has got as high as 40 billion m³ in 30 years, which harm the farming, forestry, animal husbandry and fishery production drectly. Some suggestions for soil and water conservation were pointed out: 1) strenghten vegetation construction and improve slopiing field; 2) popularize comprehensive control; 3) carry out household or families responsibility for soil erosion control; 4) collect funds from multi-source to increase outlay; 5) consummate control and management policy and carry on active propaganda.

Abstract:The Yunan Dabie mountain range with area of 2 million heectares is an important wood and grain base in Henan Province. The soil erosion and water loss is serious because of nature and social conditions. The situation of soil erosion problems and their controls were investigated and analyzed, which presented some suggestions for soil and water conservatian and production development.

Abstract:The experimental data of sediment runoff in 3 years were analyzed in this paper. The results showed that: 1) The sediment runoff in slope wasteland was smaller than in slope cropland. 2) In cropland where the coverage was less than 30%, its silt runoff was greater than in wasteland. 3) If the gradient was greater than 25, the yield would decrease significantly after 3years cultivation though better output might get at start, and caused seriously soil erosion. So the perennial heeded to be planted. The results from the experiment also showed that the sediment mainly came from sloping field in granite area, the comprehensive control in slope cropland was the main way in increasing per unit yield and soil and water conservation.

Abstract:Based on the experimental results, the law of soil erosion blackland of Changbei mountain, northeastern China, was expounded in this paper, and the conservation and yield increasing benefit under different controlling measures in hilly sloping field of national commodity grain base were analyzed. The effective measures for transforming middle and low yield field and increasing the agricultural developing Stamina were proposed. The achievemment of this experiment had a great value for popularizaton and utilization, and for new steps of agriculture development.

Abstract:In this paper, the GM(1,1) model for developing sheep husbandry is built, that is, X_（k+1）⁰=135919.6772e^0.0283062081+8715.3224e⁽-2.638216866-26187.4039. Besides, after a suggestion having been put forward the composition of sheep colony is optimized by using the methods both linear programming and traditional, and the result shows that the sheep quantity will be 200000 in 2000 and the ratio of the goat guantity and the sheep is 3.23:1.