https://www.selleckchem.com/products/as1517499.html The concentrations of Cd and Cu in soil profile samples decreased with depth, with highest concentrations at the surface, indicating the strong effect of industrial activities. Arsenic concentrations varied little with soil depth due to its strong migration ability in alkaline soil, again suggesting an industrial source. Among them, the soil of study area was severely contaminated by Cd and Cu (Level 5). Cd poses a severe potential ecological risk (Level 5) and Cu poses a medium risk (Level 2) in the study soils, while other heavy metals show low potential ecological risk (Level 1). The order of the risk identified was Cd > Cu > Ni > As > Pb > Cr > Zn. In addition, the combined potential ecological risk of heavy metals in the target area is severe. The principal component analysis showed that the high As, Cd, and Cu contents are mainly derived from industrial areas. Therefore, it is urgent to remediate Cd and Cu soil contamination in this area and implement precautions to limit As contamination.Focusing on low biogas yields in the anaerobic co-digestion of waste activated sludge and food waste, the enhancing effects and mechanisms of microscale zero valent iron (mZVI) on anaerobic co-digestion was investigated. The results indicated that the addition of mZVI enhanced the methanogenesis stage of co-digestion but had no significant effect on the solubilization, hydrolysis, and acidification stages. With a dosage of 10 g·L-1 mZVI, the cumulative methane yield (based on VS) within 15 days reached 238.68 mL·g-1, which was 20.05% higher than the control group. The mechanism analysis showed that mZVI promoted electron transport system (ETS) activity (based on INTF/TS), which increased to 21.50 mg·(g·h)-1 with 10 g·L-1 mZVI compared to 13.43 mg·(g·h)-1 in the control group. Furthermore, mZVI enhanced direct interspecies electron transfer (DIET) between specific bacteria and methanogens. Microbial community analysis demonst