State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin 150090, China; State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
State Key Laboratory of Environmental Criteria and Risk Assessment, and State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
J Hazard Mater. 2024 Jun 5;471:134398. doi: 10.1016/j.jhazmat.2024.134398. Epub 2024 Apr 23.
Livestock manure is often contaminated with heavy metals (HMs) and HM resistance genes (HMRGs), which pollute the environment. In this study, we aimed to investigate the effects of the aqueous phase (AP) produced by hydrothermal carbonization (HTC) of sewage sludge (SS) alone and the AP produced by co-HTC of rice husk (RH) and SS (RH-SS) on humification, HM bioavailability, and HMRGs during chicken manure composting. RH-SS and SS increased the humic acid content of the compost products by 18.3 % and 9.7 %, respectively, and significantly increased the humification index (P < 0.05) compared to the CK (addition of tap water). The passivation of HMs (Zn, Cu, As, Pb, and Cr) increased by 12.17-23.36 % and 9.74-15.95 % for RH-SS and SS, respectively, compared with that for CK. RH-SS and SS reduced the HMRG abundance in composted products by 22.29 % and 15.07 %, respectively. The partial least squares path modeling results showed that SS and RH-SS promoted compost humification while simultaneously altering the bacterial community and reducing the bioavailability of metals and host abundance of HMRGs, which has a direct inhibitory effect on the production and distribution of HMRGs. These findings support a new strategy to reduce the environmental risk of HMs and HMRGs in livestock manure utilization.
畜禽粪便常被重金属（HMs）和重金属抗性基因（HMRGs）污染，从而污染环境。本研究旨在探讨单独热解水热碳化（HTC）污水污泥（SS）产生的水相（AP）和稻壳（RH）和 SS 共热解水相（RH-SS）对鸡粪堆肥腐殖化、HM 生物有效性和 HMRGs 的影响。与 CK（添加自来水）相比，RH-SS 和 SS 分别将堆肥产物中腐殖酸的含量提高了 18.3%和 9.7%，并显著提高了腐殖化指数（P<0.05）。RH-SS 和 SS 对 HMs（Zn、Cu、As、Pb 和 Cr）的钝化作用分别比 CK 提高了 12.17-23.36%和 9.74-15.95%。与 CK 相比，RH-SS 和 SS 分别使堆肥产物中 HMRG 的丰度降低了 22.29%和 15.07%。偏最小二乘路径模型结果表明，SS 和 RH-SS 促进了堆肥腐殖化，同时改变了细菌群落，降低了金属的生物有效性和 HMRGs 的宿主丰度，这对 HMRGs 的产生和分布具有直接的抑制作用。这些发现支持了一种新的策略，可降低畜禽粪便利用中 HMs 和 HMRGs 的环境风险。
