Abstract

Research on the vertical differentiation of sierozem profile characteristics can provide a basis to implement soil resource assessment and develop sustainable land management system. In this study, 189 sampling data from 50 sierozem profiles along Yili River-valley in northwest of China were chosen to analyze the vertical change of edaphic characteristics and soil ionic composition – including soil organic matter (SOM), pH value, electrical conductivity (EC), total salinity (TS), contents of CO₃^2-, HCO₃^-, Cl^-, SO₄^2-, K⁺, Na⁺, Ca²⁺and Mg²⁺ in soluble salt. Then sierozem characteristics in Yili-River valley were compared with those in central Asia, Ningxia and Gansu provinces to reveal the vertical change and regional difference. The results showed that vertical difference of sierozem profile characteristics in different regions had some common: SOM content decreased with soil depth, while pH value, EC, contents of TS and most ions increased with soil depth. But there was obvious regional difference in spatial variation and intensity of sierozem characteristics due to more arid climate in Yili-River valley. The results could be used for regional ecological construction and sustainable development.

Key words: Yili-River valley, sierozem, vertical differentiation.