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Hydrochemistry is an important parameter for wetland water environmental assessment. To study the hydrochemistry and main ion sources in the Qilihai wetland in Tianjin, river water, groundwater, and water in the marsh were collected and analyzed. The results show that① The river and marsh waters are SO4·Cl-Na in type and groundwater water is HCO3-Na and HCO3-Na·Ca in type. The water in the marshes is mainly recharged by river water and the exchange of shallow groundwater with river water is notable; ② Precipitation has little effect on the chemical composition of the water. Na+ and K+ were derived from the dissolution of salt rock and evaporative concentration. Ca2+, Mg2+, and HCO3- in the river and marsh water are mainly derived from the dissolution of evaporite salt rock. Ca2+, Mg2+, and HCO3- in the groundwater are mainly derived from carbonate mineral dissolution; ③ The hydrochemical composition of the river water and groundwater is notably affected by ion exchange, but this was not observed in the marsh water. Furthermore, SO42- and NO3- are affected by human activity. During the dry season, the river and marsh water are affected by evaporite salt rock dissolution, evaporation, and human effects, while in wet season, river water is mainly affected by carbonate dissolution and human activities. These observations demonstrate how that hydrochemical composition of this wetland is controlled by a combination of natural factors and human activities.Groundwater is an important water source in the central Guohe River basin but pollution and water quality deterioration present a significant challenge. Here, 80 groups of groundwater samples were collected between June and September 2019 including 61 groups of shallow groundwater samples, 9 groups of middle groundwater samples, and 10 groups of deep groundwater samples. The hydrochemical characteristics and formation mechanisms of groundwater at these different depths were analyzed using statiatical techniques, Piper triangular diagrams, Gibbs figures, and ion ratios. The following results were noted① Groundwater is weakly alkaline overall, and the dominant anion and cation at different depths were HCO3- and Na+. The shallow and deep groundwater mainly consist of fresh water while the middle groundwater is mainly brackish water. The hydrochemical typology of the shallow groundwater was mainly HCO3-Ca·Mg and HCO3-Na·Mg. HCO3·SO4·Cl-Na was found to be the dominant hydrochemical typology in the middle and deep f ground subsidence and the contamination of the deep water with middle brackish water, deep groundwater exploitation wells should be carefully positioned and regulated.Antibiotic resistance genes (ARGs) are considered emerging contaminants posing an increasing threat to the ecological environment and global human health. Profiling ARGs in tailings ponds is essential to better understand their spatial and temporal dynamics. In this study, high-throughput quantitative polymerase chain reaction (PCR) techniques were used to investigate the occurrence, diversity, abundance, and distribution of ARGs in a tailings pond. A total of 97, 52, 44, and 56 ARGs were detected in WK0, WK1, WK2, and HS, respectively, with 11, 6, 3, and 6 mobile genetic elements (MGEs) also being detected, respectively. The absolute abundance of ARGs in the pond water ranged from 6.39×107 to 1.75×108 copies·L-1. Additionally, the abundance of MGEs were higher than ARGs in WK1 and WK2, indicating the potential for horizontal gene transfer (HGT). Furthermore, Cu, TOC, and MGEs were significantly associated with ARGs. Indeed, redundancy analysis (RDA) revealed that Cu, TOC, and MGEs explained 61.64% of the alteration of the ARG profiles, implying their potential roles in the spread and evolution of ARGs in tailings ponds.Emerging contaminants including antibiotics and antibiotic resistance genes (ARGs) have been frequently detected in drinking water resources. In this study, the occurrence of antibiotics and ARGs in various environmental matrices in representative drinking water sources in Jiangsu Province and their influencing factors were explored. Five representative drinking water sources in northern, central, and southern Jiangsu were selected. Water, surface sediment, and epilithic biofilm samples were harvested near the water intakes of each water resource in December 2018 and June 2019. The concentrations and abundances of ten antibiotics, one integrase gene intl1, and seven common ARGs were measured. The results suggest that the concentrations of the target antibiotics and ARGs are relatively low compared to previously reported data in China and elsewhere in the world. The target antibiotics were detected in all of the water sources. The concentrations of sulfonamides in the water, surface sediment, and epilithic biocal basis for ARGs pollution control and safety guidelines for drinking water resources.To explore water-air carbon dioxide (CO2) exchange and its nutritional controls in karst rivers, water sampling and analyses were conducted in the Furong River as a representative karst river system. Regional hydrometeorological characteristics, carbonate system parameters, total organic carbon (TOC), nutrients and their stoichiometric ratios, and the riverine pressure of aqueous CO2 (pCO2) and its couplings to trophic status were analyzed. The results showed that gas transfer velocity of CO2 (k) varied between 2.71 and 13.0 m·d-1. Riverine pCO2 varied from 78.5 Pa to 21491.2 Pa and was significantly higher in the tributaries than the main stem. Riverine TOC, total nitrogen (TN), and total phosphorus (TP) concentrations were (302.8±50.1), (128.9±67.9), and (0.65±0.98) μmol·L-1, respectively, demonstrating the trophic status of P-limitation. Riverine pCO2 was tightly linked to P-related parameters, suggesting that in-situ metabolism triggered aquatic CO2 supersaturation. Water-air CO2 flux (F) averaged (534.5±801.4) mmol·(m2·d)-1 in the Furong River, which is higher than most of the world's rivers, and thus indicates high potential CO2 emissions.Methane is an important greenhouse gas and whether reservoirs act as a source or sink of methane has attracted great attention worldwide. However, unrepresentative sampling periods and a lack of consideration of unfavorable weather conditions have limited the accurate estimation of CH4 emission from reservoirs. This study focused on the middle reach of Xiangxi Bay in the Three Gorges Reservoir to track an entire rainfall-runoff event via on-site measurements in the summer of 2019, and initiatively investigated the impact of rainfall and inflow processes on methane concentration and emission. NSC 27223 Results showed that from before to after the rainfall event, methane flux at the air-water interface ranged between 0.011 and 0.326 mg·(m2·h)-1, indicating a net source of methane to the atmosphere. Both wind velocity and rainfall affected methane evasion from the surface by altering the gas transfer velocity, with the effect of wind being more prominent. Methane concentrations at the bottom layer significantly increased when rainfall-induced density flow from the watershed arrived at the sampling section.