Analysis of Soil Fertility Quality and Heavy Metal Pollution in the Dawen River Basin, China

Abstract

Understanding the soil fertility status and heavy metal pollution is of great significance for targeted environmental management and governance in a basin. The Dawen River Basin (DRB), a sub-basin in the lower Yellow River area in China, was taken as the study area. A total of 107 surface soil samples were collected in the DRB in October 2019, and the sampling points were mainly located within 10 km of the mainstream of the Dawen River. Based on the measured soil nutrient indicators (organic matter, total nitrogen, total phosphorus, and total potassium) and heavy metal contents (As, Hg, Cd, Cr, and Pb), the status and spatial distribution of soil fertility and heavy metal pollution in the DRB were evaluated by combining the use of the Nemerow index method, the land accumulation index method, and the general Kriging interpolation method. The results showed that the soil fertility in the DRB was generally at a normal level or below, while some areas of Taian City, Xintai City, and Ningyang County had relatively high soil nutrient content. The content of heavy metals in the soil of the DRB was mainly at a safe level, but the single pollution index and geo-accumulation index implied that there was light to moderate pollution of heavy metals in individual samples, and the content of heavy metals in urban and industrial agglomerations is relatively high.