南疆土壤的属性分类及其类间界限指标的初步研究

本文通过大量剖面资料,应用综合数值分析法分类,取得了南疆各类土壤的主成份方程、散点图和类间界限指标等结果,为南疆例行分类系统的修订,提供了较充分依据。经32个剖面验证表明,其结果可供今后南疆土壤调查制图参考。这样的属性分类,还有利于野外识别土壤和确定其改良的难易程度,使调查成果发挥实效。着重讨论了南疆盐土与盐化土壤的分类(级)的界限指标。其划分盐土的指标主要有五项,关键是整盐、Na⁺和3.43%的表盐。

PRELIMINARY STUDY ON THE CLASSIFICATION OF SOIL PROPERTIES AND THE INDEXES OF INTERCLASS DELIMITATION OF SOILS IN SOUTH XINJIANG

The statistical values of various properties of the soils developed on pluvial-alluvial and alluvial plains in South Xinjiang were obtained by analytical method of synthetic value (AMSV) on the basis of large amounts of data of soil properties, which is helpful for comprehension of the characteristics of the soils in the region. Simultanously, the principal composition equation, scattered point graph a.nd indexes of interclass delimitation of soils in the region were obtained, which provides the possibility for correction of the existing soil classification system of the region. Results from 32 profiles showed that the results obtained from this approach could be used as the reference for the classification of the soils in the region.This classification has also been proved advantageous not only to discriminate the soils from the data of field survey or remote sensing, but also to determine the poAssibility of soil improvement. It was showed from the results obtxined that all residual saline soil was not suitable for reclamation.In addition, the indexes of interclass delimitation for saline and salinized soils in the region are discussed. Five factors including salts in whole profile (0-100 cm),Na⁺, salts in surface soil (0-30 em),Cl^- and salts in subsoil (31-100 cm)were used as the indexes in which salts in whole profile, Na⁺ and salts in surface soil are oonsidered as the more important indexes.