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一、前言土壤是一个极为复杂而又极不均一的群体。其成分包括无机的和有机的;有生命的和无生命的等等,加上它的数量之多,单是一公顷田的表土就达225万公斤左右。因此,在这样一个极不均一而且数量又如此之大的群体中,要采集1—2公斤甚至几百克样品来代表它的全体,应该说是相当困难的。有人应用统计研究来确定在一定面积范围内的采样数目。毫无疑问,这自然是一种十分简便的办法。但由于每种土壤甚至每块土地不均一的程度绝不是千
I. Introduction Soil is an extremely complex and extremely inhomogeneous group. Its composition includes inorganic and organic; living and inanimate, etc., plus its quantity as much as 2.25 million kilograms of topsoil per hectare of field alone. Therefore, in such a very heterogeneous and so large population, it is rather difficult to collect 1-2 kg or even a few hundred grams of sample to represent its entire population. Someone uses statistical research to determine the number of samples over a range of areas. There is no doubt that this is a very easy way. However, the degree of inhomogeneity of each type of soil or even each type of soil is by no means a thousand