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China has set up ecological protection and high-quality development of the Yellow River Basin as its national strategy. However, the fragile natural ecosystem and intensive human disturbances pose challenges to it. This study evaluates habitat quality change and analyzes its drivers in a representative county of this region, aiming to provide scientific basis for ecological protection and sustainable development. We took Liulin, a representative county of middle Yellow River Basin as the study area and evaluated the spatiotemporal variation of habitat quality from 2000 to 2020 with the InVEST model. Further, the influencing factors of habitat quality pattern were explored using GeoDetector, and their gradient ranges dominating the habitat quality change were determined by gradient analysis. The results showed that: (1) Areas of low and medium-low habitat quality grades were distributed interactively in the whole county; medium grade areas were scattered in the northeast and southwest parts of the county; and medium-high and high grades area were distributed sporadically along the Yellow River and its branches. (2) Habitat quality of the county almost unchanged from 2000 to 2010. However, from 2010 to 2020, with the rapid expansion of construction land (increased by 9.62 times), the area proportion of medium, medium-high, and high habitat quality grades decreased from 7.01% to 5.31%, while that of low and medium-low habitat quality grades increased from 92.99% to 94.69%. (3) The habitat quality was influenced by multiple natural-human factors. The main influencing factor was land use, followed by elevation. (4) Most changes of habitat quality occurred in areas with lower elevation, gentler slope, and higher vegetation coverage, which were affected by intensive human activities. These results suggest that in future land use policy making and, the construction land expansion in Liulin County should be restricted and differentiated ecological protection and restoration strategies should be implemented in areas with different habitat quality.

The concentrations of pollutants in soil samples collected in and around a dumpsite in Heze, Shandong, China, were investigated, and the potential ecological and health risks of these pollutants were assessed. Seventeen soil samples from five different locations were analysed for pollution characteristics, and the target pollutants included inorganic pollutants and heavy metals as well as volatile organic compounds/semivolatile organic compounds (VOCs/SVOCs). Results showed that the mean concentration level of each pollutant from the interior area was relatively higher than that from the boundary area of the dumpsite. Inorganic pollutants and heavy metals were detected in all of the soil samples. According to potential ecological risk assessment with environmental background values of Shandong as screening values, heavy metals in majority of the samples pose low ecological risk to the ecosystem except Hg. Hg poses a considerable or very high risk because of its high levels of accumulation. In consideration of future land use pattern, human health risks derived from environmental exposure to heavy metals were assessed. Carcinogenic risk and noncarcinogenic hazards for adults are acceptable, while noncarcinogenic hazards for children exceed the safety threshold. The health risks are primarily attributed to oral exposure to As and Cr.

The distribution of antibiotic resistance genes (ARGs) derived from compost in soil–plant systems is a serious issue. One possible remedy is the application of biochar-containing compost. In this study, cucumber quality and the abundance of ARGs in soil–cucumber systems under different compost treatments, namely, traditional pig manure and corn straw compost (PC); pig manure, corn straw, and large particle size biochar (5–10 mm) compost (PCLB); and pig manure, corn straw, and small particle size biochar (<2 mm) compost (PCSB); were investigated. The results showed that, under PCSB, the yield, vitamin C and soluble protein content of the cucumbers were the highest, while the absolute abundance of intI2 was reduced in the soil. The amount of available potassium in the soil contributed the most to changes in cucumber yield and quality. The total absolute abundance of ARGs in the soil was highest in PC, followed by PCLB, PCSB, and CK (control treatment without fertilization) treatments. Compared to CK treatments, PCLB and PCSB applications to the soil decreased the abundance of sul1 and tetG by 42–57% and 38–80%, respectively, in the cucumbers. In summary, the PCSB application was more beneficial in increasing soil nutrient content; improving cucumber yield, vitamin C, and soluble protein content; and reducing the risk of input and transport of ARGs in the soil–cucumber system.