渗滤液泄漏对周围土壤和地下水的安全构成严重的环境风险。更快地反映垃圾填埋场渗漏的方法是减轻垃圾填埋场生态风险的前提。在这项研究中,选择了两个垃圾填埋场(BJ和WZ)来研究沿渗流土壤深度的各种污染物的浸出特征。底层土壤的理化性质,包括NO3--N,NO2--N,NH4+-N,OM,TN,EC和Cl-沿深度表现出典型的浸出动力学。其中,TN,NH4+-N,OM,NO3--N,和EC可用作特征污染物来评估垃圾填埋场的渗滤液泄漏问题。硫假单胞菌属,不动杆菌,假单胞菌,和Hydrogenispora在底层土壤中占主导地位。与BJ样品相比,在WZ样品中观察到能够进行碳和氮循环的更加多样化和活跃的微生物组,这主要归因于不同类型土壤中含有的养分和元素。在环境因素中,含氮化合物,SO42-,pH和EC对底层土壤微生物群落结构有显著影响。Hydgenispora和Caldicopropacter的相对丰度可用作特征性微生物,以评估垃圾填埋场的渗滤液泄漏问题。这些结果提供了对底层土壤渗滤液渗漏影响的深入了解,特别是污染物的垂直分布和相应的微生物群落结构。
Leachate leakage poses a serious environmental risk to the safety of surrounding soils and groundwater. A much faster approach to reflect landfill leakage is the premise to mitigate the ecological risk of landfills. In this study, two landfills (BJ and WZ) were selected to investigate the leaching characteristics of various pollutants along the vadose soil depths. The physiochemical properties of underlying soils including NO3--N, NO2--N, NH4+-N, OM, TN, EC and Cl- exhibited a typical leaching dynamic along the depths. Among them, TN, NH4+-N, OM, NO3--N, and EC might be used as characteristic pollutants to evaluate the leachate leakage issues in landfilled sites. The genera Thiopseudomonas, Acinetobacter, Pseudomonas, and Hydrogenispora dominated in underlying soils. Compared to BJ samples, a more diverse and active microbiome capable of carbon and nitrogen cycles was observed in WZ samples, which was mainly ascribed to nutrients and elements contained in different types of soils. Among the environmental factors, nitrogenous compounds, SO42-, pH and EC had significant effects on the microbial community structures in the underlying soils. The relative abundances of Hydrogenispora and Caldicoprobacter might be used as characteristic microorganisms to evaluate the leachate leakage issues in landfilled sites. These results provided a deep insight into effects of leachate leakage in underlying soils, especially the pollutants vertical distribution and the corresponding microbial community structures.