Sources of and Control Measures for PTE Pollution in Soil at the Urban Fringe in Weinan, China

Lei Han,Leshi Li,Zhao Liu,Shanshan Chang,Risheng Li,Rui Chen,Yonghua Zhao,Longfei Xia

doi:10.3390/land10070762

Abstract

The environment of the urban fringe is complex and frangible. With the acceleration of industrialization and urbanization, the urban fringe has become the primary space for urban expansion, and the intense human activities create a high risk of potentially toxic element (PTE) pollution in the soil. In this study, 138 surface soil samples were collected from a region undergoing rapid urbanization and construction—Weinan, China. Concentrations of As, Pb, Cr, Cu, and Ni (Inductively Coupled Plasma Mass Spectrometry, ICP-MS) and Hg (Atomic Fluorescence Spectrometry, AFS) were measured. The Kriging interpolation method was used to create a visualization of the spatial distribution characteristics and to analyze the pollution sources of PTEs in the soil. The pollution status of PTEs in the soil was evaluated using the national environmental quality standards for soils in different types of land use. The results show that the content range of As fluctuated a small amount and the coefficient of variation is small and mainly comes from natural soil formation. The content of Cr, Cu, and Ni around the automobile repair factory, the prefabrication factory, and the building material factory increased due to the deposition of wear particles in the soil. A total of 13.99% of the land in the study area had Hg pollution, which was mainly distributed on category 1 development land and farmland. Chemical plants were the main pollution sources. The study area should strictly control the industrial pollution emissions, regulate the agricultural production, adjust the land use planning, and reduce the impact of pollution on human beings. Furthermore, we make targeted remediation suggestions for each specific land use type. These results are of theoretical significance, will be of practical value for the control of PTEs in soil, and will provide ecological environmental protection in the urban fringe throughout the urbanization process.

Highlights

As the provider of resources and the recipient of emissions from human activities, soil is an important contributor to the survival of the human environment
The current study focuses on Weidong New District in Weinan, Shaanxi Province, China, which is an area located on an urban fringe with numerous industrial facilities, such as cement, chemical, vehicle repair, machinery, and coal plants, which may cause heavy metal pollution in the soil
In the process of urbanization, due to the broad range of land use changes and the distribution of small and medium-sized enterprises, the environment is strongly affected by human activities and there is a potential risk of potentially toxic element (PTE) pollution in the soil

Summary

Introduction

As the provider of resources and the recipient of emissions from human activities, soil is an important contributor to the survival of the human environment. With the acceleration of industrialization and urbanization, the pollutants discharged from industry, transportation, and daily life are increasing, which brings about new challenges to the environment [4,5,6,7]. Due to their potential toxicity, high degree of concealment, and irreversible characteristics, potentially toxic elements (PTEs) are representative pollutants in industrialized societies and have become a problem that people urgently need to understand and solve [8,9,10]. Mercury can sink into the liver, causing great damage to the brain, nerves, and vision, and cadmium can cause hypertension, cardiovascular disease, and cerebrovascular disease, but can damage bones, the liver, and kidneys and cause renal failure [11,12]

Methods

Results

Conclusion