Natural and anthropogenic sources of atmospheric dust at a remote forest area in Guizhou karst region, southwest China

Abstract

The abundance and distribution patterns of Rare Earth Elements (REE) in atmospheric dust in a typical karst forest area of the Maolan National Nature Reserve Park in Southwest China were determined during the period from May 2009 to January 2011. Total REE concentrations (ΣREE) recorded moderate seasonal variation, ranging from 31.0 mg kg −1 to 88.2 mg kg −1 , with an average of 53.5 mg kg −1 , similar to the ΣREE of local topsoil. The values of ΣREE were negatively correlated with the corresponding dust deposition fluxes, which may be due to different rates of deposition as a function of particulate size. PAAS-normalized REE patterns of the dust showed slightly positive Ce anomalies and enrichment in light REE. Most dust samples had similar PAAS-normalized REE patterns to local topsoil, whereas others were similar to the anthropogenic input material from urban areas.