论土种单元的划分

我国土壤基层分类的研究尚属薄弱环节.解放前,土壤基层分类采用美国的土系制;解放初期采用苏联的土种制和连续命名法;1958年全国第一次土壤普查中,改用农民习用的土壤名称,独立命名,一直沿用至今,而未对这些命名加以系统提炼和整理,对土壤基层分类缺乏明确的原则和标准.

ON THE CLASSIFICATION OF SOIL AT SOIL SPECIES LEVEL

The patterns of solum structure for distinguishing taxa at soil species level consist of basic horizons including surface (ploughing) horizon,and other special horizons,which are naturally differentiated and arranged within the soil profile.For comparative study,the thickness and positron of the basic horizons and speaal horizons in the profile of a depth or 1m.are delimited and defined according to the criteria designed especially for delimitation of the pattern of solum structure.Within a soil genus,the pattern of solum structure is the basis for distinguishing soil species.Under the conditions of soil formation including the integrated influence of natural factors and human activity,the development degree of the diagnostic horizons combined with the differences of soil fertility in surface (ploughing) horizons may serve as the criteria for distinguishing soil species.In this paper,the procedure for classification of soil at the soil species level is discussed.