摘要
【目的】探讨原始及铁改性生物质炭对复合污染农田土壤中养分及砷(As)、铅(Pb)生物有效性的影响。【方法】分别采用质量分数为2%的原始细叶榕Ficus microcarpa生物质炭(FMB)和聚合硫酸铁改性细叶榕生物质炭(Fe-FMB)与受砷铅复合污染土壤混合,以未施加生物质炭的土壤作为对照,进行水稻Oryza sativa盆栽试验,测定不同生长阶段土壤养分、土壤酶活性以及水稻各器官和土壤中As和Pb的质量分数。【结果】与对照组相比,Fe-FMB显著提高了土壤中磷(P)、硅(Si)等养分的有效性(P<0.05),显著改变了土壤中硅(Si)的形态分布,主要增加了无定型硅(增加25.2%)和铁锰氧化态硅质量分数(增加11.1%)。Fe-FMB对于土壤和水稻稻谷中As的钝化效果更为显著(P<0.05);而FMB在钝化土壤Pb方面表现更佳,对Pb有效性最高降低了24.9%。此外,Fe-FMB还显著提升了土壤中亮氨酸氨基肽酶、酸性磷酸酶及过氧化氢酶的活性(P<0.05),增幅分别达121.1%、99.1%及33.2%。Pearson’s相关性分析结果表明,土壤酶活性与pH及土壤As有效性显著相关(P<0.05),说明施用生物质炭可通过调节土壤pH及As有效性来影响土壤酶活性。【结论】原始细叶榕生物质炭适用于修复单一Pb污染土壤。相比之下,铁改性生物质炭在修复砷铅复合污染土壤方面展现出更好的应用前景。
[Objective]To investigate the effects of raw and iron-modified biochar on the nutrient content and bioavailability of arsenic(As)and lead(Pb)in con-contaminated agricultural soil.[Method]An experiment using rice potted in soil mixed with 2%raw Ficus microcarpa biochar(FMB)and Polyferric Sulfate(iron)-modified biochar(Fe-FMB)was conducted,no biochar soil as control.Soil nutrient availability,soil enzyme activity,rice biomass and As and Pb concentrations in various plant organs at different growth stages were measured.The bioavailable As and Pb in the soil were determined using the NH_(4)H_(2)PO_(4)and DTPA extraction methods,respectively.[Result]The results indicated that,compared to the control,Fe-FMB significantly enhanced the availability of nutrients such as phosphorus(P)and silicon(Si)in the soil and significantly altered the distribution of Si forms in the soil(P<0.05),primarily increasing the content of amorphous silicon(by 25.2%)and iron-manganese oxidized silicon(by 11.1%).Fe-FMB was more effective in immobilizing soil As(P<0.05),reducing it by 37.9%compared to the control,while original biochar(FMB)was more effective for soil Pb immobilization,reducing it by 24.9%.Application of Fe-FMB led to a 67.2%reduction in As content in rice grains as compared to the control.Furthermore,Fe-FMB significantly increased the activities of leucine aminopeptidase,acid phosphatase,and catalase(P<0.05),with maximum increases of 121.1%,99.1%,and 33.2%,respectively.Pearson correlation analysis showed that soil enzyme activity was significantly related to pH and As availability(P<0.05),indicating that biochar application can regulate soil enzyme activity by influencing soil pH and As bioavailability.[Conclusion]While F.microcarpa biochar is effective in remediating soils contaminated with Pb only,it is not suitable for the treatment of soils co-contaminated with As and Pb.On the other hand,iron-modified biochar shows a better prospect for remediating soils co-contaminated with As and Pb.
作者
毛浩楠
杨兴
陆扣萍
吴家森
王海龙
MAO Haonan;YANG Xing;LU Kouping;WU Jiasen;WANG Hailong(College of Environment and Resources/College of Carbon Neutrality,Zhejiang A&F University,Hangzhou 311300,Zhejiang,China;School of Ecology and Environment,Hainan University,Haikou 570228,Hainan,China;School of Environmental and Chemical Engineering,Foshan University,Foshan 528000,Guangdong,China)
出处
《浙江农林大学学报》
CAS
CSCD
北大核心
2024年第6期1222-1232,共11页
Journal of Zhejiang A&F University
基金
国家自然科学基金资助项目(22276031)。
关键词
生物质炭
重金属
土壤修复
硅
土壤酶
biochar
heavy metal
soil remediation
silicon
soil enzyme
