Abstract:Field experiments on the plantation of Sesbania aegyptica were carried out on the saline soils of Pan-chin,Liaoning,during the years of 1957-1964.Its effect on the amelioration of saline soils was studied.Results obtained may be summarized as follows:Sesbania aegyptica is a legume plant highly tolerent both to salinity and waterlogging.The plant will stand at the salt concentrations of 0.42-1.04% in the seedling stage and of 0.93-1.39% toward the maturity.It may survive for 15-20 days on water-logged soil with flooding water to a depth of 5-30 cm.

Abstract:Field experiments concerning the effect of magnesium fertilizers on the growth and yield of soybean,peanut,rice and milk vetch (Astragalus Sinicus) were carried out on some upland and paddy soils derived from red clay and red sandstone in Kiangsi Province.Results revealed that an application of MgS0₄ (at a rate of 15 Kg Mg/hectare) to upland soils could increase the yield of soybean and peanut to about 20%.In paddy soils,a better response to magnesium fertilizer was found in milk vetch than in the succeeding rice plants.

Abstract:1.По признакам почвенных профилей,их физическим и химическим свойствам изучилн осбенности обеспеченности этихпочв питательными вешествамн.

Abstract:Рисовые почвы со свойством быстрого оседания являются одной из самых салопронзводительных почв на территории красноземых холмов.

Abstract:For the purpose of systematic study of the effect of winter wheat,field experiments were made in the central part of Shensi Province,China.The results obtained were summarized as follows:1.Summer plowing can improve the physical,chemical and biological properties of soil,and may be used as an important method for increasing the yield of winter wheat on the upland regions.

Abstract:The present paper deals with the physical and morphological studies of soil structure.In view of the fact that the aggregates formed by organic colloids are high both in water stability and porosity,effective on the improvement of soil structure and on the augmentation of soil fertility,and that those formed by clay and other cemented inorganic materials,though high in water.stability,are low in porosity,unable to ameliorate soil structure and to increase soil fertility.The soil fertility,as affected by the content of water stable aggregates,depends,on the whole,upon the conditions in which the aggregates are formed.In the soil of good structure,well developed porosity represented by the augmentation of the total and non-capillary porosity,the porasity of aggregates and the porosity filled with capillary water may improve the physical properties of soils,increase aeration and water percolation and prevent to some extent from water evaporation.

Abstract:Pot culture experiments were carried out on the black soil from Harbin and the paichiang soil from Hwachuan Hsien,both of Heilungkiang Province.Application of superphosphate alone increased the yield of wheat in the paichiang soil but not in the black soil.Combined application of nitrogenous and phosphatic fertilizers increased the yield of wheat in both soils.

Abstract:For the purpose of calculating the banding energies of sodium and potassium ions in relation to the electric charge of soils,ration activities of the suspension in equilibrium with various types of soils or clays carrying different electric charge were measured with glass electrode.It was found that far the same soil type the bonding energy was a function of the relative proportion of the clay concentration to the total concentration of rations in the system.The bonding energy of a lateritic soil was changed when the soil particles were coated with a layer of ferric oxides so as to alter their electric charge.Changes of bonding energy were also found when the ration-exchange capacity of a bentonne clay was decreased by thermal treatment.With respect to the soil type,it was shown that the bonding energies of the yellowish brown earth were almost double thar of the lateritic soil.The pH of the medium affected the bonding energy markedly,even for the bentonite clay or ration-exchange resin with little or no variable electric charge.

Abstract:A mica-like mineral with 12.5 Å basal spacing found in the soils of western Hopei was identified as biotite-vermiculite interstratified mineral.Treatment with N KCl at room temperature changed this mineral into 10 Å biotite readily,while the N MgCl₂ treatment at 100℃ gradually converted it into 14Å vermiculite.39 mini-equivalents of potassium per 100℃ grams of sample were fixed during the KCl treatment,and consequently the ration exchange capacity of the mineral was reduced in about the same amount.This interstratified mineral seems to be a weathering product of biotite.

Abstract:The viscosity of the solution of humic acid,fulvic acid and hvmatomelanic acid extracted from some soils was studied.Results obtained indicaed that they are all nonspherical colloid.The intrinsic viscosity of them in 0.1N NaCl is of following decending order:fulvic acid>humic>hymatomelanic acid.

Abstract:Главными почвамн в этом районе являются красноэёмы.