| Panzhihua is in the valley of Jinshajiang River which is the major ecological construction section at the upper reaches of Changjiang River. The silt from Panzhihua will cause the accumulation at the lower reaches of Jinshajiang River, which will threaten the flood draining and shipping. The large part of the silt would run into Sanxia Reservoir and accumolate, which would definitely reduce the profit and duration of Sanxia Project. The discharge of silt in reservoir has always been the biggest problem in concerning academia, and there has not been an effective solution yet.According to the analysis on the intensity of main water,landscape evaluation of investigation area and soil loss source in Panzhihua and the impact factors, the erosion law can be found, which will be helpful for this city to take the pointed measures of cure, to cut the discharge of silt into Jinshajiang River and Changjiang River and to do the unified plan and research on the construction of ecological environment, as well as the water and soil conservation, so that the concemning work could be steadily, ordered moved on. It is also convenient for the agency to make specific annual implementation schedule and it can be the basis of application for the cure budget, which would be brought into the annual plan of investment.This paper mainly focuses on the following points: the key factor, which contains the climate, topography, geology, soil, plant, analysis of water and soil loss in Panzhihua; conneting the formula of soil erosion modulus with local investing data to analyze and calculate the concerning factors and the moduluse, analyze the landscape impact level of investigated area; integrating the results of indoor analysis with outdoor investment to propose the effective cure measures for various of source. The survey indicates that:1) According to the data of field investment in Panzhihua, the summary suggests that the water and soil loss source can be divided into eight kinds: mining sites, quarry, closed or abandoned mine/ quarry, ballast area, remnant slope, digging breach, constructing grading, land reclamation and dust.2) The R value of annual average rain erosion in Panzhihua is 275.27. in terms of the local soil type and the destruction on upper soil layer by exploitation, the range of soil erodability factor is from 0.278 to 0.374, the gradient and slope length factor is from 0.148 to 6.384, the vegetational cover factor is 0.67 to 1 and the measures of water and soil conservation factor is from 0.5 to 1. the most serious loss site is ballast area, whose soil erosion modulus reaches 73340t/km~2·a, while the lightest one is remnant slope, whose modulus is only 570t/km~2·a3) There have been significant differences of various soil erosion moduluse. Those of ballast area, mining sites and constructing grading of stone is the largest. It respectively reaches to 48118 t/km~2·a and 41249 t/km~2·a, so the water and soil loss is the most serious; while those of remnant slope, digging breach, constructing grading, natural soil and water loss area and steep slope exploitation areas relatively have the larger average ones which respectively reaches to 20942 t/km~2·a, 28237 t/km~2·a, 21766 t/km~2·a, 15785 t/km~2·a, 27511 t/km~2·a and the intensity level of water and soil loss is fierce. Additionally, those of closed or abandoned mine/ quarry are the smallest ones which reaches to 10515 t/km~2·a and the intensity level is intense. Combined with all the impact factors, it can be concluded that when the rain factor is fixed, the most crucial factor is the gradient and slope length, whose degree of influence can reach the most significant, while other factors, such as soil erodability, vegetational cover and the measures of water and soil conservation, may vary with the variety of soil types.4) Integrated the above modulus and impact factors, it can be speculated that the gradient and slope length factor of those with the largest modulus, such as mining sites, quarry and ballast area, is more significant than others. The soil erodability of constructing or operating grading, mining site and quarry is easier for the surface soil has been destructed. As the restored mines/ quarry by natural vegetation and the natural water and soil loss area, the soil erosion modulus is lower. However, because of the faultiness in measures of water and soil conservation, each water and soil conservation factor is quite large, which should be the main target of the measures for preventionand cure.5) According to the statistical analysis conducted on the landscape effect degree of investigate areas, the results show that: of all the investigated areas, 20 areas have very serious landscape impact level, 30 areas have serious landscape impact level, and accounts for 64%; the general ones have 24, account for 30%; the lighter ones have 5, account for 6%.6) There are corresponding measures of prevention and cure provided according to different original water-and-soil-loss places, mainly include such engineering measures as cutting slope, hardening and flattening soil surface, constructing gutter, setting grit-aggrading pit, sediment storage dam and ballast bar wall etc. and eco-restoration measures as returning land use from farming to forestry etc..
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