四川酸性土壤石灰需求量方法的比较研究

Comparison of several lime requirement methods on acid soils in Sichuan

四川盆地的部分土壤由于酸性氮肥的大量使用以及雨水的冲刷淋蚀作用而呈现越来越酸化的趋势,故有必要通过化学法确定土壤石灰需求量。该研究的目的是比较SMP-SB、SMP-DB在确定四川酸性土石灰需要量上的准确度,并提出一种全新的确定土壤石灰需要量的方法,即滴定法。在四川盆地8处采样点采集的土壤分别用这3种方法确定石灰需要量,将土壤实际培养所得的石灰用量作为标准方法,再将上述3种方法的测定结果分别与标准法进行线形相关分析,得到与标准曲线之间的线形方程,结果发现3种方法与标准方法之间均成线性相关,在确定石灰需求量上都具有一定的准确度,但相对而言,文章提出的滴定法更准确,更适合确定四川土壤的石灰施用量。

A part of soils in Sichuan are becoming progressively more acid as a result of the irrigation and subsequent use high N fertilizer amounts for plants. It is very necessary to decide the lime requirement through chemical method. The objective of this research was to compare the abilities of selected chemical methods of determination of lime requirement to predict lime needs of Sichuan acid soil. In this experiment, we propose a new chemical method, which can predict the lime needs more accurate and large range of soil. The lime requirement values of 8 acid soils from Sichuan were determined by three methods. Three single-buffer method, double-buffer method and titration method were verified by comparing the estimated to the incubation LR, using correlation and regression techniques.