Sedimentary characteristics of ion-adsorption rare earth elements and assessment of their resource reuse potential due to soil and water erosion in western Fujian

Abstract

With severe soil and water erosion, the crucial ion-adsorption rare earth elements (REEs) have attracted much global attention. REEs play a vital role in tracing material sources and exploring sedimentary characteristics due to their unique and stable geochemistry properties. In the present work, three representational possible redeposition areas in western Fujian were selected as the study areas. The geochemical characteristics of REEs in the sediments of the study areas were evaluated to elucidate that REEs are the products of soil and water erosion and to assess their redeposition characteristics. The results of the geochemical analysis indicated that the parent rocks of the study areas are primarily upper continental felsic rocks with similar geochemical characteristics, and the sediments in the study areas are the products of migration and redeposition caused by soil and water erosion. Moreover, the statistical analysis highlighted a negative correlation between REEs and elevation as well as REEs and the relief degree on the land surface (RDLS). Thus, as a result of soil and water erosion, ion-adsorption REEs in the surface sediments migrate and redeposit in the soil and water of the downstream redeposition areas. This leads to a high re-utilization potential of REEs in the current situation of scarcity of such resources.