New insights into the controversy of reactive mineral-controlled arsenopyrite dissolution and arsenic release.

Serious arsenic (As) contaminations could commonly result from the oxidative dissolution of As-containing sulfide minerals, such as arsenopyrite (FeAsS). Pyrite (Py) and calcite (Cal) are two typically co-existing reactive minerals and represent different geological scenarios. Previous studies have shown that a high proportion of Py can generate a stronger galvanic effect and acid dissolution, thereby significantly promoting the release of arsenic.

Organic-mineral colloids regulate the migration and fractionation of rare earth elements in groundwater systems impacted by ion-adsorption deposits mining in South China.

Ion-adsorption rare earth element (REE) deposits distributed in the subtropics provide a rich global source of REEs, but in situ injection of REEs extractant into the mine can result in leachate being leaked into the surrounding groundwater systems. Due to the lack of understanding of REE speciation distribution, particularly colloidal characteristics in a mining area, the risks of REEs migration caused by in situ leaching of ion-adsorption REE deposits has not been concerned. Here, ultrafiltration and asymmetric flow field-flow fractionation coupled with inductively coupled plasma mass spectrometry (AF4-ICP-MS) were integrated to characterize the size and composition of REEs in leachate and groundwater from mining catchments in South China.

New Insights into the Role of Natural Organic Matter in Fe-Cr Coprecipitation: Importance of Molecular Selectivity.

Coprecipitation of Fe/Cr hydroxides with natural organic matter (NOM) is an important pathway for Cr immobilization. However, the role of NOM in coprecipitation is still controversial due to its molecular heterogeneity and diversity. This study focused on the molecular selectivity of NOM toward Fe/Cr coprecipitates to uncover the fate of Cr via Fourier transform-ion cyclotron resonance-mass spectrometry (FT-ICR-MS).

Co-transport of biochar nanoparticles (BC NPs) and rare earth elements (REEs) in water-saturated porous media: New insights into REE fractionation.

The present study investigated the co-transport behavior of three REEs (La, Gd, and Yb) with and without biochar nanoparticles (BC NPs) in water-saturated porous media. The presence of REEs enhanced the retention of BC NPs in quartz sand (QS) due to decreased electrostatic repulsion between BC NPs and QS, enhanced aggregation of BC NPs, and the contribution of straining. The distribution coefficients (K) in packed columns in the co-transport of BC NPs and three REEs were much smaller than in batch experiments due to the different hydrodynamic conditions.

Heavy metal contamination affects the core microbiome and assembly processes in metal mine soils across Eastern China.

Mining activities in metal mine areas cause serious environmental pollution, thereby imposing stresses to soil ecosystems. Investigating the ecological pattern underlying contaminated soil microbial diversity is essential to understand ecosystem responses to environment changes. Here we collected 624 soil samples from 49 representative metal mines across eastern China and analyzed their soil microbial diversity and biogeographic patterns by using 16 S rRNA gene amplicons.

Untangling microbial diversity and assembly patterns in rare earth element mine drainage in South China.

Ion-adsorption rare earth element (REE) deposits are the main reservoirs of REEs worldwide, and are widely exploited in South China. Microbial diversity is essential for maintaining the performance and function of mining ecosystems. Investigating the ecological patterns underlying the REE mine microbiome is essential to understand ecosystem responses to environmental changes and to improve the bioremediation of mining areas.

Genome- and community-level interaction insights into the ecological role of archaea in rare earth element mine drainage in South China.

Microbial communities play crucial roles in mine drainage generation and remediation. Despite the wide distribution of archaea in the mine ecosystem, their diversity and ecological roles remain less understood than bacteria. Here, we retrieved 56 archaeal metagenome-assembled genomes from a river impacted by rare earth element (REE) mining activities in South China.

Indicator species drive the key ecological functions of microbiota in a river impacted by acid mine drainage generated by rare earth elements mining in South China.

Acid mine drainage (AMD) generated by rare earth elements (REEs) deposits exploration contains high concentrations of REEs, ammonium and sulfates, which is quite different from typical metallic AMD. Currently, microbial responses and ecological functions in REEs-AMD impacted rivers are unknown. Here, 16S rRNA analysis and genome-resolved metagenomics were performed on microbial community collected from a REEs-AMD contaminated river.

Factors influencing heavy metal availability and risk assessment of soils at typical metal mines in Eastern China.

China exemplifies the serious and widespread soil heavy metal pollution generated by mining activities. A total of 420 soil samples from 58 metal mines was collected across Eastern China. Total and available heavy metal concentrations, soil physico-chemical properties and geological indices were determined and collected.

Cadmium stable isotope variation in a mountain area impacted by acid mine drainage.

The pollution of natural waters and sediments with metals derived from acid mine drainage (AMD) is a global environmental problem. However, the processes governing the transportation and transformation of AMD metals such as Cd in mountainous areas are poorly understood. In this study, the Cd isotopic composition and Cd concentration of river water and sediments (16 sampling sites) from an AMD-affected river in southern China were determined.