| The soil erosion is serious in Hubei province with complex topography, concentrated rainfall, large population density and strong artificial disturbance on soil. The Fourth Remote Sensing Census in 2005 showed that the soil erosion area in Hubei was up to 55,900 km2,30% part of the province's total,area and middle degree erosion area up to 26,600 km2.20cm topsoil gone per year, there would be lose 875,000 mu of plow layer soil, also losing 27,300 ton of soil organic matters. By 2007, slope farmlands area were up to 62,700 hm2,13.45% of the total farmlands in Hubei. The area of farmlands with more than 25°slope and unsuitable for cropping between 15°to 25°were up to 41,500 hm2,66.25% of total slope farmland area. The area of farmlands with the slope more than 35 was as large as 133,300 hm2, being 2.12% part of total slope farmland area. In the past 50 years,600 million mu of farmlands in Hubei have been subjected to water and sand damage, making plow layer thinning and productivity declining.To make less loss in water and soil and improve the condition of ecology, economy and society, conservation of water and soil is being practical used in Hubei Province. Numerous soil conservation monitor stations were founded in whole province range to accumulate a lot of runoff plots'data after monitoring for several decades. These data are very essential for soil erosion study and soil conservation measure in this region. Base on that above, this study would widely get the data together from all over of the monitor stations in Hubei to analyze impact on slop runoff and sediment by using Meta-analysis in 3 aspects of land use, water and soil conservation measure and slope degree.Meta-analysis is a specialized statistic technology that can integrate the individual data under independent research,and now it has been developed into a research method. This paper describes the theory and steps of Meta-analysis in detail. It compares with the traditional overview as well in order to elucidate the advantages of this method. In this paper meta-analysis is used to analysis the land use, water and soil conservation measure and slope degree impacts on slope runoff and sediment. Then it discusses the results.The following major conclusions are obtained:(1)Due to the variance of vegetation coverage and infiltration properties in different land use patterns, farmland, garden plot, woodland and grassland have different effects on runoff and sediment declining. To sum up, farmland has heavier soil erosion than garden land, woodland and grassland.(2) Due to different water and soil conservation measures, slope farmlands are of different water and soil loss situation. The analysis result shows that slope runoff and sediment yield on straight ploughing is more than that on Contour ploughing; Grass-bush intercropping, slope terrace and level terrace all have good effect on controlling runoff and sediment on slope.(3)On certain slope degree scale, slope runoff and sediment yield increase with slope degree going up. In this paper it has a grate promoting effect on runoff when slope degree is more than 15°;the slopes with degree between 10°to 20°are less in sediment yield, and more than 25°are obvious in increasing sediment yield.(4) This paper shows that major harness on soil conservation in hillside area should put on slope farmlands, barren slope and barren hill, putting an end in blindly reclamation in slope region. Implement grain-grass-bush intercropping and rotation, developing agroforestry on slope farmland less than 15°;adapting to local conditions and transforming slope into terrace on farmland over 15°,meanwhile developing economic forests; carry on conversion of cropland to forest and grass step by step on slope above 25°;planting trees and grasses on low coverage rate regions as barren hill slope.Through this study we expect to provide an integrated configuration in water and soil conservation measures, a sustainable development of soil ecological environment and a theoretical basis of adjust land use structure in hillside of Hubei Province.
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