Polyacrylamide (PAM) has been used extensively due to its well-known stable chemical properties, but limited information is available on the biodegradation of soil-containing PAM. In this work, sufficient degradation of PAM was achieved via the addition of the Klebsiella sp. PCX-biochar composite to PAM-containing soil, due to the synergic effect of bio-augmentation and bio-stimulation. The optimal degradation rate of 69.1% over 30-day period was observed under the following conditions: the addition of immobilized bacteria at 0.07 g/g, pH 6.6, and temperature at 38.0 ^oC. In this study, we showed that PAM was successfully hydrolyzed by amidase, and ammonia in the hydrolysis product was then oxidized by the nitrifying bacteria. The decrease of water-extractable organic carbon (WEOC) also demonstrated the chain cleavage in PAM. PAM was utilized as a carbon source not only by Klebsiella sp. PCX but also by some taxa from indigenous bacteria. Last but not least, it was shown in this study that biochar, even though immobilized with exogenous microorganisms, actually enhanced bacterial diversity and stimulated the growth of some indigenous PAM-degrading taxa. Based on the above observations, we concluded that PAM biodegradation via the addition of bacteria-immobilized biochar was a synergy of both bio-augmentation and bio-stimulation strategies.

聚丙烯酰胺（PAM）由于其众所周知的稳定化学性质而被广泛使用，但是有关含土壤PAM的生物降解的信息有限。在这项工作中，通过添加克雷伯氏菌（Klebsiella sp。）实现了PAM的充分降解。由于生物增强和生物刺激的协同作用，PCX-生物炭复合物可与含PAM的土壤形成复合物。在以下条件下，观察到30天的最佳降解率为69.1％：添加固定化细菌的浓度为0.07 g / g，pH值为6.6，温度为38.0 ^oC.在这项研究中，我们表明酰胺酶成功地水解了PAM，然后水解产物中的氨被硝化细菌氧化。水溶性有机碳（WEOC）的减少也证明了PAM中的链断裂。PAM不仅被克雷伯菌（Klebsiella sp。）用作碳源。PCX还可以通过某些分类单元从本地细菌中获得。最后但并非最不重要的一点是，该研究表明，即使被外源微生物固定，生物炭实际上仍可增强细菌多样性并刺激某些降解PAM的本地类群的生长。基于以上观察，我们得出结论，通过添加细菌固定化的生物炭来进行PAM生物降解是生物增强和生物刺激策略的协同作用。