Bioretention systems are a low-impact development (LID) measure to effectively control stormwater runoff and reduce pollutant concentrations. In this paper, three groups of bioretention cells with different filling materials (1# bioretention soil media (BSM), 2# BSM + 5% biochar, and 3# BSM +5% biochar +biological filler) were constructed to analyze the pollutant removal characteristics and microbial action under different simulated rainfall conditions. Results showed that the overall pollutant removal capacity of systems 2# and 3# was higher than that of system 1#, with system 3# having the lowest effluent concentrations of 2.71 mg/L for total nitrogen (TN) and 64.3 mg/L for chemical oxygen demand (COD). The load reduction effect for heavy metals of the three systems was ranked as 2# > 1# > 3#, and average load reduction rates were 80.3, 75.1, and 84.8% for Cu, Pb, and Zn in 2#. Microbial community analysis indicated that Proteobacteria and Firmicutes were the absolute dominant bacteria of the three bioretention systems, and the dominant genera included Bacillus, Hyphomicrobium, Micrococcaceae, and Nitrospira. In addition, the total number of denitrifying functional bacteria genera in systems 2# and 3# was increased by 1.39 and 52.1% compared to system 1#.

生物滞留系统是一种低影响开发（LID）措施，可有效控制雨水径流并降低污染物浓度。本文构建了三组不同填充材料的生物滞留池（1#生物滞留土壤介质（BSM）、2#BSM+5%生物炭、3#BSM+5%生物炭+生物填料）来分析污染物去除效果不同模拟降雨条件下的微生物特征及作用。结果表明，2#、3#系统总体污染物去除能力高于1#系统，其中3#系统出水浓度最低，总氮（TN）为2.71 mg/L，总氮（TN）为64.3 mg/L。化学需氧量（COD）。 3个系统重金属减载效果排序为2#>1#>3#，2#中Cu、Pb、Zn平均减载率分别为80.3%、75.1%、84.8%。微生物群落分析表明，变形菌门和厚壁菌门是三个生物滞留系统的绝对优势菌，优势菌属包括芽孢杆菌属、丝微菌属、微球菌科和硝化螺菌属。此外，系统2#和3#中反硝化功能菌属总数较系统1#分别增加了1.39%和52.1%。