Abstract:The present paper deals with results of preliminary studies on the microbiological properties of the sand dunes in Tengkeli desert of Ninghsia province.It reveals the following facts:1.The relative number of microorganisms and the composition of microflora in the fixed sand dunes are quite different from those in the mobile sand dunes.Larger number of microorganisms with higher activity have been found in the fixed sand dunes than in mobile sands.It also indicates that the fixation of the sands under the influence of the growth of high plants is an essential factor in improving soil fertility.2.In the fixed sand dunes,more microorganisms with higher activity exist in soils of rhizosphere of high plants.It shows that the root development of high plants has a significant influence to the microflora.3.A greater number of microorganisms also exist in the surface crust of sand dunes in comparison with the corresponding subsoils.The activity of microorganisms may give a definit affect on the formation of soil surface crust.The role of microorganisms in the process of fixing the sand dunes needs further investigations.

Abstract:Tatung basin is situated in the Northern part of Shansi province.The genetic soil type is light chestnut earth formed under the dry steppe condition.The alkalized soils are scattered among the light chestnut earths on the higher river terraces,while on the depressed low terraces and in the flood plain large areas of saline soils arc formed under the high water table and mineralized ground water conditions.In the joint position of these two terraces the soda-saline soils are distributed.From the analytical data of ground water,soils and rocks,the soda is originated from the transformation of sodium silicates in weakly mineralized ground water as proposed by Professor Kovda.Moreover the analytical data also show that there are large quantities content of sodium compounds in the igneous rocks in the surrounding mountainous regions.This might be another origin furnishing large amount of soda to both ground water and soils.

Abstract:"Дуншуйтяиь" распространяются на платформе,сложенной из переотложения Поелеяанского периода.

Abstract:Краасноземовидные рисовые почвы широко распространеы в центральной части провинции Цзянси.

Abstract:"Лоуту" является старопахотной окультуренной почвой,образующейся на мощной лессовой материнской породе.

Abstract:The determination of mineral nitrogen in soils has been successively done by Conway's diffusion method.Owing to the high content of amraonical nitrogen present in most manures,and also to the turbidity of their extracts,this method fails to give good duplicates in ammonia determination from separated aliquots.The present article gives a modified technique of Conway's procedure for the extraction and determination of ammonical nitrogen in manures with percentage recovery ranging 97.2-104%.5 drams of sample are extracted by a 10% KCl-0.1N HCl solution with sample-extractant ratio from 1:10 to 1:20 or even wider in case of manures with exceedingly high content of ammonical nitrogen.A 2 ml aliquot,containing NH₄-N-100γ is used for analysis.The distillation of NH₄-N can be completed in 24 hrs by MgO displacement in Conway's dish at room temperature.