Anaerobic oxidation of methane driven by different electron acceptors: A review.

Methane, the most significant reduced form of carbon on Earth, acts as a crucial fuel and greenhouse gas. Globally, microbial methane sinks encompass both aerobic oxidation of methane (AeOM), conducted by oxygen-utilizing methanotrophs, and anaerobic oxidation of methane (AOM), performed by anaerobic methanotrophs employing various alternative electron acceptors. These electron acceptors involved in AOM include sulfate, nitrate/nitrite, humic substances, and diverse metal oxides.

Coupled processes involving ammonium inputs, microbial nitrification, and calcite dissolution control riverine nitrate pollution in the piedmont zone (Qingshui River, China).

Rivers in agricultural countries widely suffer from diffuse nitrate (NO) pollution. Although pollution sources and fates of riverine NO have been reported worldwide, the driving mechanisms of riverine NO pollution associated with mineral dissolution in piedmont zones remain unclear. This study combined hydrogeochemical compositions, stable isotopes (δO-NO, δN-NO, δO-HO, and δH-HO), and molecular bioinformation to determine the pollution sources, biogeochemical evolution, and natural attenuation of riverine NO in a typical piedmont zone (Qingshui River).

Evolution of groundwater hydrochemical characteristics and formation mechanism during groundwater recharge: A case study in the Hutuo River alluvial-pluvial fan, North China Plain.

A pilot project for groundwater recharge from rivers is currently being carried out in North China Plain. To investigate the influence of river recharge on groundwater hydrochemical characteristics, dynamic monitoring and analysis of groundwater samples were conducted at a typical recharge site in the Hutuo River alluvial-pluvial fan in the North China Plain from 2019 to 2021. Hydrochemical, isotopic, and multivariate statistical analyses were used to systematically reveal the spatiotemporal variation of groundwater chemistry and its driving factors during groundwater recharge process.

Spatio-temporal analysis of the sources and transformations of anthropogenic nitrogen in a highly degraded coastal basin in Southeast China.

Nitrogen transport from terrestrial to aquatic environments could cause water quality deterioration and eutrophication. By sampling in the high- and low-flow periods in a highly disturbed coastal basin of Southeast China, hydrochemical characteristics, nitrate stable isotope composition, estimation of potential nitrogen source input fluxes, and the Bayesian mixing model were combined to determine the sources and transformation of nitrogen. Nitrate was the main form of nitrogen.

Pollution characteristics and health risk assessment of arsenic transformed from feed additive organoarsenicals around chicken farms on the North China Plain.

Arsenic is frequently found in poultry waste, most of which is transformed from feed additive organoarsenicals, resulting in arsenic pollution of soils and water around poultry farms. The North China Plain, an important area for livestock breeding of China, was chosen to investigate the pollution characteristics and assess the health risk of arsenic around chicken farms. Among the 138 chicken farms sampled, almost no roxarsone, a common organoarsenical, was detected in chicken feeds, manure, and surface soils, while the detectable rate of other arsenic species was high.

Determining the origin and fate of nitrate in the Nanyang Basin, Central China, using environmental isotopes and the Bayesian mixing model.

Identifying sources of nitrate contamination has been a long-term challenge in areas with different land uses. We investigated the biogeochemical processes and quantified the contribution of potential nitrate sources in the Nanyang Basin, the source area of the South to North Water Diversion Project in China. Hydrogeochemical characteristics, the dual-isotope method (δN-NO and δO-NO), and the Bayesian mixing model (SIAR) were combined.

Iodine enrichment and the underlying mechanism in deep groundwater in the Cangzhou Region, North China.

The lack of information on the origin and behavior of iodine in deep groundwater restricts the development and use of groundwater resources. To address this issue, the Cangzhou region in the eastern North China Plain (NCP) was selected for a case study. In total, 296 deep groundwater samples were collected, their iodine concentrations were determined, and the distribution characteristics of iodine concentrations were analyzed.

[A clinical study on clamp technique of intraocular lens on anterior capsule in cases with big rupture of posterior capsule of lens].

Objective: To investigate the long-term results of the clamp technique of the posterior chamber intraocular lens (IOL) on the anterior capsule of lens in cases with big rupture of posterior capsule of lens.

Methods: The clamp technique of the posterior chamber IOL on the anterior capsule of lens were performed on 48 eyes of 48 cases with big rupture of the posterior capsule of lens following extracapsular cataract extraction for senile, traumatic, complicated and diabetic cataract. After 3-60 months follow-up, the vision acuity, position of IOL, capsular opacity and post-operative complications were investigated.