摘要
为探究外源添加物如何影响水稻根际微环境,进而对水稻Cd积累过程产生影响,采用生物炭(BC)和丛枝菌根真菌(arbuscular mycorrhiza fungi,AMF)作为非生物与生物制剂的代表,联合添加修饰水稻根际环境应对土壤Cd污染。结果表明:生物炭和AMF的添加均促使土壤有机质质量分数提高,且对土壤有效磷、速效钾质量分数以及土壤碳、氮固定具有积极的影响,同时缓解了Cd胁迫对土壤脲酶的活性抑制作用,使土壤DTPA-Cd占比从58.95%提高到64.42%;Cd胁迫影响了水稻根际土壤微生物群落的丰富度和多样性,而生物炭和AMF的添加促使土壤中变形菌门的丰度由29.7%恢复到33.1%;土壤Cd质量分数为1 mg/kg时,BC+AMF处理组较CK处理组Bacillus群落丰度提高88.5%;在5 mg/kg土壤Cd胁迫下,生物炭和AMF的联合施加使水稻根系Cd积累量占比由CK处理组的60.4%提高到联合处理组的77.1%,而籽实Cd积累量占比由4.4%降低到1.6%;生物炭和AMF的施加可通过提高水稻根际土壤的营养条件和微生物群落结构和功能,促进Cd在水稻根系的固定,减少了向地上部籽实的迁移。这一结果为联合生物和非生物因子对重金属污染土壤环境的改善提供了理论支持。
This study aims to elucidate the effects of exogenous additives on the rhizospheric microenvironment of rice and their subsequent influence on Cd accumulation.Biochar(BC)and arbuscular mycorrhizal fungi(AMF)were utilized as representatives of abiotic and biotic agents,respectively,jointly added to modify the rice rhizosphere in response to soil Cd contamination.Results show that the incorporation of both biochar and AMF significantly enhanced the soil organic matter content,thereby exerting a positive impact on the levels of available phosphorus,available potassium,and soil carbon-nitrogen fixation.Furthermore,these additives mitigated the inhibitory effects of Cd stress on soil urease activity,resulting in an increase in the proportion of DTPA-extractable Cd from 58.95%to 64.42%.Cd stress significantly influenced the richness and diversity of the microbial community within the rice rhizosphere soil.The addition of biochar and AMF facilitated the recovery of the abundance of the proteobacteria phylum,increasing from 29.7%to 33.1%.At the 1 mg/kg soil Cd,the abundance of the Bacillus community in the BC+AMF treatment group increased by 88.5%compared to the CK treatment group.Under a stress condition of 5 mg/kg soil Cd,the synergistic application of biochar and AMF resulted in an increase in the proportion of Cd accumulation within the rice root system,rising from 60.4%in the CK group to 77.1%in the BC+AMF treatment group,concurrently reducing the proportion of Cd accumulation in the seeds from 4.4%to 1.6%.The addition of biochar and AMF improved the nutritional conditions and the structure and functionality of the microbial community in the rice rhizosphere soil,thereby facilitating the sequestration of Cd within the rice root system and diminishing its translocation to the aboveground seeds.These findings offer substantial theoretical support for the integrated application of biotic and abiotic factors in the remediation of heavy metal-contaminated soil environments.
作者
赵廷
杨基先
汤丁丁
薛强
刘东斌
王立
ZHAO Ting;YANG Jixian;TANG Dingding;XUE Qiang;LIU Dongbin;WANG Li(State Key Laboratory of Urban Water Resource and Environment(Harbin Institute of Technology),Harbin 150090,China;China Construction Third Bureau Green Industry Investment Co.,Ltd.,Wuhan 430074,China)
出处
《哈尔滨工业大学学报》
北大核心
2025年第5期11-21,共11页
Journal of Harbin Institute of Technology
基金
国家自然科学基金(52270154)。
关键词
重金属
根际固定
丛枝菌根真菌
秸秆生物炭
水稻
heavy metal
rhizosphere immobilization
arbuscular mycorrhizal fungi
straw biochar
rice
