摘要
为探讨原始和铁改性生物质炭对污染土壤中砷(As)和铅(Pb)生物有效性和土壤微生物群落结构的影响,利用As-Pb复合污染水稻土进行水稻盆栽试验,分别在土壤中施加3%(质量分数)的原始法国梧桐枝条炭(法桐炭)、铁改性法国梧桐枝条炭(Fe-法桐炭)、原始猪炭(猪炭)、铁改性猪炭(Fe-猪炭).试验结束后测定土壤pH、有机碳等理化性质、土壤养分有效性、土壤有效态As和Pb、稻谷中As和Pb的含量及土壤微生物群落结构等指标.结果表明,与对照相比,施用Fe-法桐炭对土壤中As的钝化效果较好,降幅为39%;施用猪炭对土壤中Pb的钝化效果较好,降幅为19%;Fe-法桐炭的施用使稻谷中As含量降低了80%.施用两种原始生物质炭后,土壤中的微生物群落多样性指数(Chao1、Shannon)和OTUs总数均显著)增加(p<0.05),但相较于原始生物质炭,施用铁改性生物质炭均提高了土壤中优势菌群的相对丰度,且两种铁改性生物质炭处理土壤中的优势菌属为Actinobacteria_unclassified、Gaiellales_unclassified和Nocardioides.冗余分析表明,土壤中微生物群落组成与土壤pH和有效态As关系密切.因此,施用生物质炭可以通过改变土壤pH和降低As胁迫等性质影响土壤微生物群落结构.综上所述,经过铁改性处理的法桐炭更适用于As污染土壤修复,而原始猪炭是一种比较理想的Pb污染土壤修复材料.
To investigate the effects of raw and iron-modified biochars on the bioavailability of arsenic(As)and lead(Pb)and functional diversity of the microbial community in soils,a pot experiment was carried out using a paddy soil contaminated by As and Pb.In the pot experiment,3%(W/W)of raw Platanus orientalis Linn branch-derived biochar(GWB),Fe-modified Platanus orientalis Linn branch-derived biochar(Fe-GWB),raw pig carcass-derived biochar(PB),and Fe-modified pig-derived biochar(Fe-PB)were respectively applied to the soil.Non-amended soil served as the control.Soil pH,organic carbon content,nutrient availability,concentrations of NH4H2PO4-extractable As and DTPA-extractable Pb in soils,the concentrations of As and Pb in rice grains,and the microbial community structure in soils were determined.Results showed that,compared to the control,application of Fe-GWB decreased the concentration of NH4H2PO4-extractable As by 39%,while application of PB decreased the concentration of DTPA-extractable Pb by 19%.Application of Fe-GWB reduced the concentration of As in the rice grains by 80%.The microbial community diversity(Chao1,Shannon)and OTUs number of both raw biochar treatments significantly increased when compared to the control.However,iron-modified biochars were more effective in increasing the abundance of the dominant microflora,which were Actinobacteria Unclassified,Gaiellales Unclassified and Ncardioides.Redundancy analysis showed that the microbial community composition was significantly related to soil pH and the concentration of NH4H2PO4-extractable As in soils.Therefore,application of biochar can affect soil microbial community structure through changing soil pH and reducing As stress.In conclusion,the Fe-modified Platanus orientalis Linn branch-derived biochar was a suitable material for remediation of the soil contaminated with As,whereas the pig carcass-derived biochar was an optimal material for mitigating Pb contamination in the soil.
作者
戴志楠
杨兴
陈翰博
陈俊辉
张妍
王海龙
DAI Zhinan;YANG Xing;CHEN Hanbo;CHEN Junhui;ZHANG Yan;WANG Hailong(School of Environmental and Resource Sciences,Zhejiang A&F University,Hangzhou 311300;School of Environmental and Chemical Engineering,Foshan University,Foshan 528000)
出处
《环境科学学报》
CAS
CSCD
北大核心
2022年第7期456-465,共10页
Acta Scientiae Circumstantiae
基金
国家自然科学基金(No.21876027)
佛山市社会领域科技攻关项目(No.2120001008392)
广东省基础与应用基础研究基金(No.2019A1515111024)。
