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Analysis of water balance in the middle reaches of the Yellow River is important for the effective water resources management, ecological protection, and high-quality development in the Yellow River Basin. The Qinhe River Basin, located at the end of the middle reaches of the Yellow River, has serious water problems, such as, river interruption and insufficient inflow into the Yellow River, due to the implementation of the upstream water diversion policy and the increase in domestic and industrial water use. To address the water problems, the water resource demand, water supply capacity, and supply-demand balance of the basin were analyzed based on the ecological water demand. The results show that (1) the spatial distribution of water supply and water demand in the Qinhe River basin is heterogeneous. All the upstream river reaches in the Shanxi Province are able to guarantee the ecological water demand in the river channel, while in the downstream Henan Province, only the minimum water demand can be met; (2) the total suppliable water resources in the Qinhe River basin is 10.04×108 m3, and the sum of industrial, domestic, and ecological water use outside the river channel is 8.89×108 m3. The remaining water in the river channel is only 1.15×108 m3, which can only meet the minimum ecological water demand; (3) the amount of surface water used by industrial production and life in the basin will be 6.98×108 m3 in 2030, and the total amount of water use will be 9.81×108 m3, resulting in that the remaining water cannot support the minimum ecological water demand. We pose five suggestions for the water problem in the Qinhe River Basin: Reducing the industrial water consumption, improving the water utilization rate of agricultural irrigation, promoting water conservation technologies with high effectiveness, and improving the ecological environment. This study can provide basic information for the effective water resources management in the Qinhe River basin.

[Objective] The impacts of a metal mine on the surrounding grassland were studied, and the ecological environment was evaluated using remote sensing technology as a significant aid to ecological restoration and environmental protection of mining areas. [Methods] The study was conducted at a desert-steppe gold mine located in an ecologically fragile area. Spatial and temporal dynamics of normalized difference vegetation index (NDVI) in the mine area were analyzed based on long time series remote sensing data to conduct a comprehensive evaluation of the ecological quality of the study area using the remote sensing ecological index (RSEI). [Results] The impacted area of desert-steppe gold mining was determined as the area with a radius of 5 km outward from the mine boundary. There was a fluctuating increase in NDVI values in the mine and impact areas that varied with the duration of mining in the steppe from 2009 to 2021. The annual average value of NVDI within the mine area during the underground mining operation period was 51.9% higher than during the open pit mining operation period. In addition, the impact of open pit mining on vegetation in the study area was higher compared with underground mining. The RSEI values in the mining area and the impacted area initially increased, then decreased, and then stabilized, resulting in an overall non-significant increase. The spatial distribution of RSEI indicated that the areas with poor ecological environmental quality in the mine and impact areas were mainly the waste dump and surrounding area. [Conclusion] Gold mining influenced the surrounding desert grassland within a radius of 5 km from the mine. The ecological environment of the mine and the impacted area gradually improved through management efforts during mining. Ecological restoration and environmental management of the waste dump and the surrounding area should be strengthened during the process of mine ecological construction.

Due to their significant environmental impact, there has been a gradual restriction of the production and utilization of legacy per- and polyfluoroalkyl substances (PFAS), leading to continuous development and adoption of novel alternatives. To effectively identify the potential environmental risks from crop consumption, the levels of 25 PFAS, including fourteen perfluoroalkyl acids (PFAAs), two precursor substances and nine novel alternatives, in agricultural soils and edible parts of various crops around a fluoride industrial park (FIP) in Changshu city, China, were measured. The concentration of ΣPFAS in the edible parts of all crops ranged from 11.64 to 299.5 ng/g, with perfluorobutanoic acid (PFBA) being the dominant compound, accounting for an average of 71% of ΣPFAS. The precursor substance, N-methylperfluoro-octanesulfonamidoacetic acid (N-MeFOSAA), was detected in all crop samples. Different types of crops showed distinguishing accumulation profiles for the PFAS. Solanaceae and leafy vegetables showed higher levels of PFAS contamination, with the highest ΣPFAS concentrations reaching 190.91 and 175.29 ng/g, respectively. The highest ΣAlternative was detected in leafy vegetables at 15.21 ng/g. The levels of human exposure to PFAS through crop consumption for various aged groups were also evaluated. The maximum exposure to PFOA for urban toddlers reached 109.8% of the standard value set by the European Food Safety Authority (EFSA). In addition, short-chained PFAAs and novel alternatives may pose potential risks to human health via crop consumption.