利用离心法进行土壤颗粒分级

Soil particle size fractionation with centrifugation method.

按照离心机MandalRC5C的转子尺寸 ,根据Stocks公式对Anderson和Tiessen的土壤颗粒分级方法中的离心时间重新设定 .用新设计出的土壤颗粒分级方法对 3种黄土高原的土壤 (黄绵土、灰褐土、黑垆土 )和 2种加拿大北美大草原的土壤 (典型褐灰钙土、典型黑灰钙土 )进行了分组 ,其结果与吸管法所得的结果相吻合 ,表明这一分级方法的分析误差小、适用的土壤范围广 ,可用于土壤有机质、土壤中N、P、S等元素在不同粒径中分布等研究 .同时 ,讨论了利用超声波进行土壤颗粒分散技术的使用条件 。

According to the rotor size of Mandal RC5C and Stoks' law,a segregation procedure for soil particle size fractionation was designed,and used for the particle separation of Huangmian soil(Calcaric cambisols,FAO),Huihe soil(Haplic greyxems,FAO),and Helu soil(Calcic kastanozems,FAO) in the Loess Plateau of China,and of Orthic Brown Chernozem,and Orthic Black Chernozem in Canadian Prairie.The fractionation results of the 5 soils by using this procedure were in line with those of the standard pipette method.