烷烃胁迫下土壤微生物类群的应激响应及其降解特性  

The response of soil microbial groups to alkane stress and hydrocarbon biodegradation characteristics

作　　者：欧娅雯 陈龙 李丹洁 吴蔓莉[1] 许殷瑞 王琪 冯爽 OU Yawen;CHEN Long;LI Danjie;WU Manli;XU Yinrui;WANG Qi;FENG Shuang(Shaanxi Key Laboratory of Environmental Engineering,Key Laboratory of Northwest Water Resource,Environment and Ecology,Xi’an University of Architecture and Technology,Xi’an,710055,China;The Eighth Oil Production Plant of Changqing Oilfield,PetroChina,Yulin,718699,China)

机构地区：[1]陕西省环境工程重点实验室,西北水资源与环境生态教育部重点实验室,西安建筑科技大学环境与市政工程学院,西安710055 [2]中国石油长庆油田分公司第八采油厂,榆林718699

出　　处：《环境化学》2024年第9期3032-3042,共11页Environmental Chemistry

基　　金：国家自然科学基金(52070154);陕西省重点研发项目(2023-YBNY-251)资助.

摘　　要：污染物胁迫条件下土壤微生物会发生应激响应,然而目前对于烷烃污染土壤中微生物类群应激响应的时效性尚不清楚.论文以人工配制的十六烷污染黄绵土为对象,利用磷脂脂肪酸-稳定同位素技术(phospholipid fatty acid technology-stable isotope probing,PLFA-SIP)探究了烷烃污染对黄绵土中生物群落组成和结构影响的时效性及烷烃降解情况.结果表明,土壤土著微生物对十六烷有一定的降解作用,培养30 d时,十六烷含量由5000 mg·kg^(-1)降低至4693 mg·kg^(-1),降解率为6.14%.土壤中各微生物类群活性在受到十六烷污染3 d时无明显变化,随污染时长的增加,各微生物类群表现出“毒性响应(污染7 d)—毒性适应(污染15 d)—生长代谢(污染30 d)”的应激过程.在污染前期(污染7 d时),G^(-)细菌的^(13)C-PLFA含量为14.52 ng·kg^(-1),占总细菌^(13)C-PLFA总量的43.40%,说明在污染前期G^(-)细菌是土壤中存在的可利用十六烷的主要优势类群;污染中后期(污染15—30 d),G^(+)细菌和真菌的^(13)C-PLFA含量分别占^(13)C总量的33.81%和22.95%,说明污染后期G^(+)细菌和真菌对十六烷的降解代谢起到主要作用.研究表明土壤中十六烷的降解需要各微生物类群的协同代谢作用,污染前期主要由r—策略微生物(G^(-)细菌)降解十六烷,污染后期则主要由k—策略微生物(G^(+)细菌和真菌)执行降解功能.研究可为探明土壤微生物类群对烷烃污染响应的时效性及不同微生物类群对污染物的利用特征提供科学依据.Soil microorganisms present the stress response to the contaminants.However,the timeliness response of the microbial community under hydrocarbon stress is unclear.In this study,the loessal soil collecting from the northern of Shaanxi province of China was used to study the effects of hexadecane pollution on the compositions and structures of microbial communities using phospholipid fatty acid technology-stable isotope probing(PLFA-SIP)techniques.Results showed that the indigenous microorganisms in the polluted soil had certain degradation capacity toward hexadecane through natural attenuation.After 30 days of incubation,the hexadecane content decreased from 5000 mg·kg^(-1) to 4693 mg·kg^(-1),with a degradation rate of 6.14%.Soil microbial community had no significant changes at the 3th days of pollution and the toxic effects appeared at the 7th days.Then soil microorganisms was adapted to alkane stress and finally exhibited growth after 15th days of incubation.In the early stage of hexadecane pollution(7 days of pollution periods),the ^(13)C-PLFA content of G^(-)bacteria was 14.52 ng·kg^(-1) which accounting for 43.40%of the total ^(13)C-PLFA.In the medium and later stages of pollution(15—30 days of pollution durations),the ^(13)C-PLFA content of G^(+)bacteria and fungi accounted for 33.81%and 22.95%of the total ^(13)C-PLFA,respectively.Result indicated that the G^(-)bacteria were the dominant microorganisms which could utilize hexadecane in the soil during the early stage,but the G^(+)bacteria and fungi played a major role for hexadecane degradation in the later stages of pollution.Studies suggested that hexadecane biodegradation in soil involved the synergistic metabolism of various microbiomes.In the early stage of incubation,r-strategic microorganisms(G—bacteria)mainly utilized easily degradable carbon components,and k-strategic microorganisms(composed of G^(+)bacteria and fungi)utilized the refractory carbon components in the later stage.This study provided a theoretical basis for the pollution timeli

关 键 词：烷烃污染土壤 PLFA-SIP 微生物群落 应激响应 生物降解 

分 类 号：X-1[环境科学与工程] O6[理学—化学]