Potentially Toxic Elements in Oasis Agricultural Soils Caused by High-Intensity Exploitation in the Piedmont Zone of the Tianshan Mountains, China

Wen Liu,Jilili Abuduwaili,Long Ma

doi:10.3390/agriculture11121234

Abstract

Considering the pollution of potentially toxic elements (PTEs) in the soils of China, the present study analyzed the current state and influencing factors of PTEs in oasis soils using the model of absolute principal component score–multiple linear regression in the piedmont zone of the Tianshan Mountains. The possible non-carcinogenic and carcinogenic risks of PTEs at current concentrations were also explored using a human-health risk-assessment model. The results suggested that the extent to which potentially toxic elements in the soils of different geographical units in the study area is affected by human activities varies considerably. The PTEs Cd and As in the soils of the Yili River Watershed were the most strongly influenced by human activities, reaching levels of 40% and 59%, respectively. However, in the Bortala River Watershed, Cu, Cd, and As were the most strongly influenced by human activities, reaching levels of 33%, 64%, and 76%, respectively. Geographical units with a high degree of economic development (e.g., the Yili River Watershed) had, in contrast, low levels of PTE pollution caused by human activities, which may be related to the regional economic development structure. The human health risk assessment showed that the non-carcinogenic and carcinogenic risks of PTEs are currently below the threshold. However, increasing the arsenic content to 1.78 times the current level in the Bortala River Watershed would lead to carcinogenic risk. For the Yili River Watershed, a 3.33-fold increase in the arsenic content above its current level would lead to a carcinogenic risk. This risk should be addressed, and targeted environmental-protection measures should be formulated. The present research results will provide important decision support for regional environmental protection.

Highlights

Introduction iationsAnthropogenic modifications of the natural environment have become more prevalent over the past century and have altered the structure and functional relationships of different ecosystems at a range of scales [1,2,3]
To quantify whether high-intensity exploitation in Xinjiang, China, has commensurately affected the potentially toxic elements (PTEs) composition and soil quality in the region, we present data from soil surveys of the PTE compositions of surface soils (0–20 cm in depth) from two major oases
There are some differences between the concentrations of key elements analyzed in the soil samples and those reported for the upper continental crust (UCC) [66]

Summary

Introduction

Anthropogenic modifications of the natural environment have become more prevalent over the past century and have altered the structure and functional relationships of different ecosystems at a range of scales [1,2,3]. Soil is the foundation of sustainable agricultural development [4,5], and soil quality has significant effects on human health. With population growth and economic development, soil environmental problems in many countries have become increasingly prominent [8,9,10]. Among soil’s geochemical components, potentially toxic elements (PTEs) are the main pollutants in farmland soils [11,12]. The pollution from PTEs in farmland soil is related to the quality and safety of agricultural products and the health of farmland ecosystems [13]

Methods

Results

Conclusion