Department of Ecology, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China.
Department of Ecology, College of Natural Resources and Environment, South China Agricultural University, Guangzhou, 510642, China; Guangdong Provincial Key Laboratory of Eco-circular Agriculture, South China Agricultural University, Guangzhou, 510642, China; Guangdong Engineering Technology Research Centre of Modern Eco-agriculture and Circular Agriculture, Guangzhou, 510642, China; Key Laboratory of Agro-Environment in the Tropics, Ministry of Agriculture and Rural Affairs, South China Agricultural University, Guangzhou, 510642, China.
Environ Pollut. 2022 Aug 15;307:119549. doi: 10.1016/j.envpol.2022.119549. Epub 2022 May 26.
Additives are considered a promising approach to accelerate the composting process and alleviate the dissemination of pollutants to the environment. However, nearly all previous articles have focused on the impact of additive amounts on the reduction of HMs, which may not fully represent the main factor shaping HMs bioavailability status during composting. Simultaneously, previous reviews only explored the impacts, speciation, and toxicity mechanism of HMs during composting. Hence, a global-scale meta-analysis was conducted to investigate the response patterns of HMs bioavailability and compost parameters to different additives, composting duration, and composting factors (additive types, feedstock, bulking agents, and composting methods) by measuring the weighted mean values of the response ratio "[ln (RR)]" and size effect (%). The results revealed that additives significantly lessened HMs bioavailability by ≥ 40% in the final compost products than controls. The bioavailability decline rates were -40%, -60%, -57%, -55%, -42%, and -44% for Zn, Pb, Ni, Cu, Cr, and Cd. Simultaneously, additives significantly improved the total nitrogen (TN) (+16%), pH (+5%), and temperature (+5%), and decreased total organic carbon (TOC) (-17%), moisture content (MC) (-18%), and C/N ratio (-19%). Furthermore, we found that the prolongation of composting time significantly promoted the effect of additives on declining HMs bioavailability (p < 0.05). Nevertheless, increasing additive amounts revealed an insignificant impact on decreasing the HMs bioavailability (p > 0.05). Eventually, using zeolite as an additive, chicken manure as feedstock, sawdust as a bulking agent, and a reactor as composting method had the most significant reduction effect on HMs bioavailability (p < 0.05). The findings of this meta-analysis may contribute to the selection, modification, and application of additives and composting factors to manage the level of bioavailable HMs in the compost products.
添加剂被认为是一种很有前途的方法，可以加速堆肥过程并减轻污染物向环境的扩散。然而，几乎所有以前的文章都集中在添加剂数量对减少重金属的影响上，而这可能不能完全代表在堆肥过程中塑造重金属生物利用度状态的主要因素。同时，以前的综述只探讨了重金属在堆肥过程中的影响、形态和毒性机制。因此，进行了一项全球范围内的荟萃分析，通过测量响应比“[ln (RR)]”和大小效应（%）的加权平均值，研究不同添加剂、堆肥时间和堆肥因素（添加剂类型、原料、膨松剂和堆肥方法）对重金属生物利用度和堆肥参数的响应模式。结果表明，与对照相比，添加剂在最终堆肥产品中使重金属生物利用度降低了≥40%。Zn、Pb、Ni、Cu、Cr 和 Cd 的生物利用度下降率分别为-40%、-60%、-57%、-55%、-42%和-44%。同时，添加剂显著提高了总氮（TN）（+16%）、pH（+5%）和温度（+5%），降低了总有机碳（TOC）（-17%）、水分含量（MC）（-18%）和 C/N 比（-19%）。此外，我们发现堆肥时间的延长显著促进了添加剂对降低重金属生物利用度的效果（p < 0.05）。然而，增加添加剂的用量对降低重金属的生物利用度没有显著影响（p > 0.05）。最终，使用沸石作为添加剂、鸡粪作为原料、木屑作为膨松剂和反应器作为堆肥方法对降低重金属生物利用度的效果最为显著（p < 0.05）。这项荟萃分析的结果可能有助于选择、修改和应用添加剂和堆肥因素来管理堆肥产品中生物可利用的重金属水平。
Zotero 插件