AUTHOR=Yu Yang , Zhang Jiapeng , Qin Jifa , Yang Jisong , Wang Zhikang , Song Ningning , Yu Junbao 

TITLE=Characteristics and influencing factors of metal distribution in different wetlands of the Liaohe Delta, Northeastern China

JOURNAL=Frontiers in Marine Science

VOLUME=Volume 9 - 2022

YEAR=2022

URL=https://www.frontiersin.org/journals/marine-science/articles/10.3389/fmars.2022.1011457

DOI=10.3389/fmars.2022.1011457

ISSN=2296-7745

ABSTRACT=The metal distribution in different wetlands under the complex influence of natural and anthropogenic activities in the Liaohe Delta was analyzed to better protect and manage delta areas. Ninety-six soil samples were collected from six wetland types and the levels, depth distributions, risk, and influencing factors of metals (i.e., As, Cd, Cr, Ni, Cu, Pb, Zn, Mn, Al, Fe) were analyzed. The results showed that the concentrations of As, Cd, Cr, Ni, Zn and Al in more than 70% of soil samples were higher than the background value of Liaoning Province. The concentrations of As decreased with the distance from the estuary, while those of Cr were higher downstream of Liaohe. The spatial distributions of Cd, Ni, Cu, Pb, and Zn were similar. The concentrations of most metals in the topsoil were higher than those in the subsoil. According to the Nemerow pollution index, higher pollution was observed in the area far away from the Liaohe River and Bohai Sea for the topsoil layer, while for the subsoil layers, higher pollution was observed in the area near the Liaohe estuary. Correlation analysis showed that wetland types were clearly correlated with Cd, Cu, Al, and S. The concentrations of Cd, Pb, Zn, C, N, P, S and electrical conductivity obviously decreased with soil depth, while the concentration of Mn was positively correlated with soil depth. Mn was negatively correlated with TOC, TN, and TP, whereas Cd, Pb, and Zn were positive correlation with TOC, TN and TS. The general Linear Modal indicated that wetland types had a significant effect on As, Cd, Ni, Cu, Pb, Zn, Al, and Fe (P< 0.01), and depth had a significant effect on Cd, Cr, and Pb (P< 0.01). The findings of this work will contribute to pollution control and ecosystem health conservation of the Liaohe Delta.