Human activities affect the concentrations and distributions of trace metals in the heavily sediment-laden Yellow River

Abstract

The increase in population, the development of industry and agriculture, and the exploitation and utilization of natural resources have inevitably caused a series of ecological and environmental problems, including trace metal pollution. Quantifying the influence of human activities on the metal concentrations of an aqueous environment is helpful for understanding the process and the relationship between socioeconomic development and ecological environmental quality at the macro level. We investigated how human activities and natural variabilities influence the concentrations and distributions of trace metals in the aquatic environment of the heavily sediment-laden Yellow River (> 5000 km). The results showed that the relevant indicators of human activities, such as the population density, average GDP, the number of industrial enterprises above a designated size, percent cropland, percent impervious surface, and the proportion of total crops sown area, had significant positive effect on the concentrations and distributions of some metals in the water environment with a weight of 33∼64%. Moreover, percent grassland and percent wetland exhibited a significant negative correlation with metals. Rapid population growth and socioeconomic development have accelerated the production of metals and other pollutants, that eventually enter the aquatic environment via runoff or other methods through a series of migrations and transformations; thus, the scope of pollution has gradually increased. Some artificially constructed prevention, control and repair measures have played a role in mitigating the effects of environmental pollutants, including metals. This study contributes to the development of effective strategies for controlling metal pollution in the Yellow River basin.