Effect of superphosphate addition on heavy metals speciation and microbial communities during composting

• Published in: Bioresource technology Vol. 359; p. 127478
• Main Authors: Li, Shuxin, Chen, Wenjie, Liu, Dun, Tao, YueYue, Ma, Hongting, Feng, Ziwei, Li, Songrong, Zhou, Kaiyun, Wu, Juan, Li, Ji, Wei, Yuquan
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2022
• Subjects: Heavy metal fractions; Microbial community; Network analysis; Pig manure composting; Superphosphate addition; Superphosphate addition; Pig manure composting; Network analysis; Microbial community; Heavy metal fractions
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2022.127478

[Display omitted] •Heavy metal and microbial community in composting with SSP addition were compared.•SSP addition limited the passivation of HMs and increased potential ecological risk.•SSP addition increased 16% core bacteria-fungi positive interactions compared to CK.•HM fractions were key factors driving microbial communities in composting added SSP.•Proteobacteria and Ascomycota were resistant and active to HM stress when SSP added. Superphosphate fertilizer (SSP) as an additive can reduce the nitrogen loss and increase available phosphorus in composting but few studies investigated the effect of SSP addition on heavy metal and microbial communities. In this study, different ratios (10%, 18%, 26%) of SSP were added into pig manure composting to assess the changes of heavy metal (Cu, Mn, As, Zn, and Fe) fractions, bacterial and fungal communities as well as their interactions. SSP addition at 18% had lower ecological risk but still increased the bioavailability of Cu, Mn, and Fe in composts compared to control. Adding 18% SSP into compost decreased bacterial number and increased the fungal diversity compared to CK. Redundancy analysis indicated heavy metal fractions correlated significantly with bacterial and fungal community compositions in composting with 18% SSP. Network analysis showed adding 18% SSP increased microbial interaction and positive cooperation especially enhanced the proportion of Proteobacteria and Ascomycota.