Research Of The Best Effect On Soil And Water Conservation And Environment Build In Mahua Valley Of Mu Danjiang City

A further study was made in this paper on the ecological project concerning water and soil conservation in watershed of outskirts, which has an immediate influence upon urban areas. Meanwhile, it listed the main research contents, approaches together with other relative problems. Taking the mountainous areas (Mu Danjiang city) in eastern Hei Longjiang province for example, the article summarized the special characteristics of water and soil conservation in small water valley of outskirts compared with that of rural areas, making it clear how water and soil run away and adverse effects to cities, proposing a theoretical method of the optimized-structure model. A representative watershed (Ma Hua valley of Mu Danjiang outskirts, Hei Longjiang province) was taken in this study, using superior programming method to design a optimized model for the water and soil conservation. According to the natural characteristics of Ma Hua Valley, considered with the specialty and requirements of soil and water conservation ecological project of city, three object functions were established. First one, pure income of soil and water conservation was maxim. Secondly, quantity of running away was minimum. Thirdly, investment of soil and water conservation was minimum.More objective program is a superior planning method. It overcomes the single shortcomings of traditional linear program objective, the limited shortcomings that the objective program method requires every objective function has expectation value, it settles the claims of meeting more objective of program at the same time. More objective policy decisions of program adopt numerical policy decision and experience decision (expert appraising method) to compare. Numerical policy decision is on the basis of the indefinite policy decision 'regret value' standard of operational and adopts mathematics formula, tabulate or the relevant method of <> through calculating the lowest grand totai value after nearing every objective function unified measure unit. So it can avoid the influence of experience to people subjective factor. Then linking experiment with production to build substance model to finish the ecological project concerning water and soil conservation in watershed of outskirts and beneficial study from information feedback.In the model construction, all the optional measures promoted and the 10 principles applied must take the city' s need as their basis and show the discrepancy between conservation in small water valley of outskirts and that of rural areas, hence make the mould more representative, more applicable and more valuable for extended use.Significant ecological profits, economic profits and social profits were obtained through ten years of research. Soil erosion intensity was reduced to 847t/km2 from the original 6196t/km2. Each item attained or surpassed the requirements of the optimum model. Quantity of drainage into city each year was reduced from 34.7 thousand tons to 6.5 thousand tons. Quantity of running earth and sands into city of the outskirts each year was reduced to 0.4 thousand tons from original 2.9 thousand million tons. Pure income and income of per person in 2002 were increased 194% and 176%, respectively.The rate of keeping water and keeping soil of every measure is defined by experimentobserving means of institute of soil and water conservation of Hei Longjiang province...