Risk of Soil Salinization Exists in Yanqi Basin of Northwest China

2014-11-27

The soil salinization processes may operate at a local or regional scale and the problem of soil salinity is becoming increasingly widespread in arid regions. Knowledge of soil salinity and its variability is essential to evaluate the extent of salt build-up. The assessment of the risk of soil salinization can contribute to sustainable land planning aimed at mitigating soil degradation and increasing crop production.

Yanqi Basin, a typical oasis in the southern Xinjiang of northwest China, has experienced soil salinization recent years as a result of economic development and human activity. So, ZHANG Zhaoyong et al. selected the Yanqi Basin as the study area to evaluate the soil salinization risk in the arid region of China. Correlation analysis, principle component analysis and cluster analysis of the classic multivariate statistical method were used to process data and identify the soil salinity.

The main salt ions were K⁺, Ca²⁺, Na⁺, Cl^-, Mg²⁺ and SO₄^2-, accounting for 84.41% of the total salt content. However, the concentrations of HCO^3- and CO₃^2- were very low. Land use types significantly influenced the soil salt properties. For example, the amounts of K⁺ and Ca²⁺ were higher in the farmland than in the forest, grassland, urban construction areas and desert. The maximum average values of K⁺, Ca²⁺, Na⁺, Mg²⁺ and SO₄^2- and total amount of salts in the farmland were higher than those in the desert, grassland and areas of urban construction.

According to the multivariable statistics analyses, all of the soil properties could be divided into four groups. Group 1 (Na⁺, Cl^-, SO₄^2-, EC and pH) and group 2 (K⁺, Ca²⁺, Mg²⁺ and total amount of salts) were mainly affected by human activities, whereas group 3 (CO₃^2-) and group 4 (HCO^3-) were mainly influenced by natural resources. Although the risk of soil salinization in the Yanqi Basin is low, soil salinization and alkalization in this basin should be noticed for sustainable development.

This research can provide helpful reference to reduce soil salinization in the Yanqi Basin. The study was published in PLOS ONE in Seotember 2014.