Abstract:According to the climatic features and the production condition of south Ningxia mountain area,we take the water-storage pIanting ditches,protected furrows and plastic film cover as an integrated techniques,by using of the methods such as tillage,cultivating,rotation planting,fertilizing,water saving and soil moisture maintaining etc.,planting crops singly or intercropping,multiping storage ditches on hilly farmland,and establishing a tillage technical system to conserve water and maintain soil moisture,and to promot the water conversing and to raise the famland productivity on such hilly land.The resuIt shows that this tillage technique is very useful in saving the precipitation and controlling the soil and water loss,so it can strengthen the drought resistance of crops,raise the water use efficiency and productivity of crops.As an average grain and oilcrop yield can get raise of 60% in single planting and intercropping planting;the rate of drought resistance,soil moisture maintain in growth period can raise of 14. 6% ~ 17.85%;soll molsture storage efficiency reached 42.5% ~71.5% higher than the traditional tillage method;the efficiency of water productivity can get of more than 40%.

Abstract:By using the method of ¹³⁷Cs to study soil erosion in the loess gully area of east Gansu province,the erosion and sediment yield coming from Yuan,slope and gully are analysised quantitively.The results show that use the biological and engineering measure to control gullies,the erosion is declined,but on the surface of Yuan,it is relatively sticking out and not be ignored.

Abstract:After studing on the distribution characteristics of soil agro-hydrology and the factors related to them in the loess region of Shaanxi province,the loess region of whole province is divided into seven sub-regions according to the leading index of soil physical clay content,and absolute moisture in the 100cm soil layer.and the differece between the precipitation and evapotranspiration. Soil agro-hydrological characteristics in each subregion are discussed,and the appropriate measures for soil improvement are put forward.

Abstract:The relationship between crop yield and both of the soil covered thickness and properties of reclaimed land within copper mine area in Shanxi province was studied.The result shows soil Physical properties as well as the capability of drought resistance are different duing to the differences of soil covered thickness.The fertility level of one--year new reclaimed land after green manuring and fertilizing is almost equivalent to that of the fifteen years old reclaimed land.The crop yield increases with the thickness of covered soil increasing.

Abstract:To take effective measures for management of young growth land,the soil structure improver hydropolyacrylonitrile was used to treat Huangmian soil in the experiment.The results show that the effects are very significant that Huangmian soil is improved by hydropolyacrylonitrile,using of which,the production of waterstable aggregates is advanced,soil density is lowered,and soil permeability raised.Moreover,within the concentration range 0.05%~0.40% of the improver,the improvemental effects to Huangmian soil will strengthened with increasing concentration.Also it is preliminarily indicated that using the improver in young growth land might increase soil moisture. Thus it is advisable that soil structure improvers would be applied to tending of young growth in poor site.

Abstract:The content of single rare--earth element at different stages and positions in corn were measured by INAA.The results show that rare--earth element absorbed by corn is mainly transported to the ripening and high living positions,corn absorbs La,Ce,Nd sensitively in each growing stage.The three elements are probably main active material in crops.

Abstract:After analysing the data of typical investigation and hydrological survey in Northwestern Shanxi province,the result shows that the calculating result would fit to the basic characteristic of storing more flood and sediment by silt arrester in the year of more flood and sediment than mormal year if we calculate the amount of annual flood and sediment reducing.A new method of calculating the sediment retaining in middle reaches of the Yellow river is suggested,it has used in the analyses of sediment and flood reducing benefits on the eight tributaries of Yellow river in northwestern Shanxi province,and a good result has been obtained.

Abstract:Jinsha river is a main sediment source in the upper reaches of the Yangzi river.Through statistical analysis to water and sediment data of major hydrological control station in Jinsha river basin,the sediment transport characteristics of the basin which include sediment sources and distribution,annual variation and annual distribution of sediment discharge,the relationship between runoff and sediment discharge,and the genesis of sediment are discussed.It provides a scientific basis for the rule of soil eorsion and sediment transportation researching,and soil and water resources reasonable developing and utilizing in Jinsha river basin.

Abstract:Urban soil and water loss is trending towards seriousness and universality.It is more necessary to control urban soil and water loss.It takes place at urban fringes,and the building actions are the radical cause of its forming.Compared with natural soil and water loss,urban soil and water loss has the features of artificiality,complexity,seriousness and regulation. Urban soil and water loss should be comprehensively controlled by coordinating the relationship between building actions and environment and restraining unreasonable action of man-kind

Abstract:Based on the observation data in cutover areas at home and abroad,soil erosion in forestry land is analysed comprehensively.The mechanism of soil erosion caused by logging operation is expounded.Meanuhile,some countermeatures to reduce soil erosion at cutover areas have been suggested

Abstract:Based on the previous researches,after comprehensively analysing to the geological and geomorphic structure,the calamity type and its influencing and stimulating factors,the rainfall intensity index at the eruption of the most serious compound debris flow,and strategies on economical development are proposed.

Abstract:Based on explaining some concepts of urban soil erosion and soil and water conservation and the necessity of developing soil and water conservation in urbanized areas,the characteristics of soil erosion occurred in urbanized areas,such as being mainly humanaffected,complexity of erosion patterns,concealment of erosive intensity and multifold sources of eroded materials etc.,have beed further discussed.There are some relative characteristics of soil and water conservation in urbanized areas also being studied,which includes special purposes and demands,key point of controlling erosion caused by human activities,involving many different aspects and regional structure of urban area,the basis of control measures for soil and water conservation etc.Furthermore,types and contents of soil and water conservation in urbanized areas have been analysed.