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Simulation results showed groundwater level drawdown would not occur synchronously in spatial, but always occurred around the tunnel axis at first and gradually expanded towards far away over time. The maximum disturbance on groundwater system can reach to approximately 25 m vertically and 3000 m horizontally for present modeling tunnel. With the aid of numeral simulation, three response stages were identified for the karst groundwater system behavior to the tunnel disturbance. The impacts of tunnel practice on groundwater and surface water bodies can be gradually eliminated since the second stage, but would continue if existing failure of tunnel waterproof until a new balance state achieved. The present research can improve the understanding of the impacts of tunnel excavation on karst groundwater system and dependent geo-environment, and provide reference to the protection of water resources and geo-environment in karst regions like Chongqing worldwide.Constructed wetland is a common measure for water purification and biodiversity conservation, but the mechanism of carbon storage is still unclear. Here, we researched the content and composition of soil organic carbon (SOC) and the influencing factors in surface sediment in surface flow constructed wetlands (SFCW) and subsurface flow constructed wetlands (SSFCW). Results showed that the content and storage of SOC in SSFCW were significantly higher than those in SFCW. However, the higher proportion of light fraction organic carbon (LFOC) and lower proportion of heavy fraction organic carbon (HFOC) in SSFCW indicated that SSFCW had less stable organic carbon storage than SFCW. 3,4-Dichlorophenyl isothiocyanate mouse The composition of SOC in the two types of constructed wetlands was mainly affected by total nitrogen, which suggesting carbon-nitrogen coupling in constructed wetlands. The abundant microbial species in SSFCW and their positive correlation with SOC could explain the higher carbon storage in SSFCW than in SFCW. In addition, plant biomass was the principle factor limiting LFOC proportion in SFCW, while it was moisture content in SSFCW. The study has important implications for understanding and management of ecological function of carbon sequestration in contrasted wetlands, and also provides a special perspective to understand the carbon storage mechanism in wetlands.Louhajang River, Bangladesh, which crosses Tangail as a densely industrialized and urbanized city, supplies water for different purposes. This study reports the levels of pH, electrical conductivity (EC), and some toxic heavy metals in 40 water samples collected during the summer and winter seasons from Louhajang River. The winter season reported higher levels of the examined parameters than the summer season with significant variation (p 1.0 × 10-6, indicating possible cancer risk. The adopted collection of different approaches (comparison against standard levels of toxicants, statistical analysis, spatial distribution, and health risk assessment) successfully demonstrates a whole picture of the environmental status of Louhajang River, Bangladesh.Passivation of heavy metals is one of the most efficient techniques to remediate soil pollution. However, passivators with single component are usually unsatisfactory in the case of multi-metal contaminated soils. To resolve this problem, a series of combined passivators containing different ratios of Fe-Mn ore, Fe powder, zeolite, bentonite, etc. were designed and used to study their effects on the growth, heavy metal accumulation, and the antioxidant response of Chinese cabbage (Brassica chinensis L.) as well as the soil available forms of heavy metals in a copper refinery's multi-metal (As, Cd, Pb, Cu) contaminated yellow-brown soil and an artificially contaminated (As, Cd, Pb, Cu) calcareous alluvial soil. The results showed that compared with the control, the addition of combined passivators significantly promoted cabbage growth, with the biomass increase up to 1.77 and 3.54 times in yellow-brown soil and calcareous alluvial soil, respectively. The activity of antioxidant enzymes (SOD, CAT, POD) and the content of malondialdehyde (MDA) and glutathione (GSH) decreased, while the chlorophyll content increased significantly, as compared with no passivators. In addition, passivator application decreased As, Cd, Pb, and Cu contents in shoots and roots by 34.8%, 45.6%, 34.9%, and 11.1% and 49.2%, 63.8%, 38.6%, and 46.4% in yellow-brown soil and by 29.8%, 27.3%, 26.8%, and 25.5% and 45.8%, 55.2%, 61.8%, and 5.7% in calcareous alluvial soil, respectively. Besides, the content of soil available heavy metals was reduced by 8.0-17.1% in yellow-brown soil and 3.3-19.1% in calcareous alluvial soil after the application of passivators. The results indicated that the combined passivators formulated in this experiment could efficiently reduce the content of the multi-metals in cabbage and relieve the oxidant stress and could be used as a way to remediate multi-metal polluted soils.Cyanobacteria are prolific producers of numerous toxic compounds, among which microcystins (hepatotoxins) are the most frequently found. Cyanobacterial bloom in freshwaters is an increasing problem, and there is still a need for rapid and reliable methods for the detection of toxic cyanobacterial samples. In the present study, the toxicity of crude extracts of 11 cyanobacterial strains from different genera has been assessed on two cell lines (human hepatocellular carcinoma HepG2 and rainbow trout (Oncorhynchus mykiss) liver-derived RTL-W1 cells), crustaceans (Daphnia magna and Artemia salina), and zebrafish (Danio rerio) embryos, as well as by protein phosphatase 1 (PP1) inhibition assay and ELISA test to determine whether the toxicity could be due to the presence of hepatotoxins/microcystins. All the tested strains exhibited toxicity on HepG2 cell line (IC50 from 35 to 702 μg mL-1), including Arthrospira (Spirulina) strains, while toxicity against the RTL-W1 cells was detected only in the positive reference Microcystis PCC 7806 and Nostoc 2S9B. Tested strains expressed higher toxicity to D. magna and zebrafish embryos in comparison to A. salina, whereby Nostoc LC1B and Nostoc S8 belonged to the most toxic strains. The PP1-inhibiting compounds have been detected by PP1 assay only in four strains (Microcystis PCC 7806, Oscillatoria K3, Nostoc LC1B, and Nostoc S8), indicating that their toxic potency can be attributed to these compounds. On the other hand, very low levels of microcystins, as confirmed by ELISA, were insufficient to explain toxicity and different toxic potencies of tested cyanobacteria. Results presented in this study suggested HepG2 cell line as a particularly suitable model for cyanobacterial toxicity assessment. In addition, they highlight terrestrial cyanobacterial strains as potent producers of toxic compounds.