Straw addition increases enzyme activities and microbial carbon metabolism activities in bauxite residue  

作　　者：Hao Wu Wei Sun Feng Zhu Yifan Jiang Shiwei Huang Johnvie Goloran Shengguo Xue 

机构地区：[1]School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China [2]School of Metallurgy and Environment,Central South University,Changsha 410083,China [3]School of Environment and Science,Griffith University,Brisbane,QLD 4072,Australia

出　　处：《Journal of Environmental Sciences》2024年第1期332-344,共13页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.42077379 and 42177391);the Natural Science Foundation of Hunan Province,China (No.2022JJ20060);the Central South University InnovationDriven Research Program (No.2023CXQD065)。

摘　　要：Recovery of microbial functions is one of the critical processes in the nutrient cycling of bauxite residue for improving revegetation.Straw is considered to be effective to increase microbial diversity and drive the development of the microbial community,but its effect on microbial carbon metabolism has not been illustrated.The present study evaluated the effects of phosphogypsum(PG),straw(SF)and phosphogypsum plus straw(PGSF)on physicochemical properties,enzyme activities,and microbial carbon metabolism activities in bauxite residue.After 180 days incubation,PG,SF and PGSF treatment significantly reduced the residue pH from 10.85 to 8.64,9.39 and 8.06,respectively.Compared to CK treatment,SF treatment significantly increased the content of total organic carbon(TOC)and organic carbon fractions(DOC,MBC,EOC,and POC).In addition,straw addition significantly increased glucosidase,cellulose,urease,and alkaline phosphatase by 7.2-9.1 times,5.8-7.1 times,11.1-12.5 times,and 1.1-2.2 times,respectively.The Biolog results showed that straw addition significantly increased microbial metabolic activity(AWCD)and diversity in bauxite residue.Redundancy analysis indicated total nitrogen(TN)and carbon fractions(POC,MBC and DOC)were the most important environmental factors affecting microbial metabolic activity and diversity in bauxite residue.These findings provided us with a biogeochemical perspective to reveal soil formation in bauxite residue and suggested that nutrient supplement and regulation of salinity-alkalinity benefit the establishment of microbial communities and functions in bauxite residue.

关 键 词：Bauxite residue Labile organic carbon fractions Enzyme activities Community-level physiological profiles Soil formation in bauxite residue 

分 类 号：X75[环境科学与工程—环境工程]