文献类型：期刊文献

英文题名：Toxic responses of microorganisms to nickel exposure in farmland soil in the presence of earthworm (Eisenia fetida)

作者：Xia, Xiaoqian[1];Lin, Siyuan[1];Zhao, Jun[1];Zhang, Wei[1];Lin, Kuangfei[1];Lu, Qiang[1];Zhou, Bingsheng[2]

机构：[1]East China Univ Sci & Technol, Sch Resource & Environm Engn, State Environm Protect Key Lab Environm Risk Asse, Shanghai 200237, Peoples R China;[2]Chinese Acad Sci, Inst Hydrobiol, Wuhan 430072, Hubei, Peoples R China

年份：2018

卷号：192

起止页码：43

外文期刊名：CHEMOSPHERE

收录：;EI(收录号：20174404330131);WOS:【SCI-EXPANDED(收录号:WOS:000418313900006)】；

基金：This research was supported by the projects of Research on Migration/Transformation and Safety Threshold of Heavy Metals in Farmland Systems (2016YFD0800405), National Key Research and Development Program of China; the National Natural Science Foundation of China (21737005, 41371467, 51708223); and the Shanghai Pujiang Program (15PJD013).

语种：英文

外文关键词：Nickel; Soil; Microorganism; Toxic response; Earthworm

摘要：Nickel (Ni)-contamination impairs soil ecosystem, threatening human health. A laboratory simulation of Ni-polluted farmland soil study, in the presence or absence of earthworm, was carried out to investigate the toxic responses of soil microorganisms, including microbial biomass C (MBC), soil basal respiration (SBR), metabolic quotient (qCO(2)), urease (UA) and dehydrogenase activities (DHA). Additionally, the variations of Ni bioavailability were also explored. Results manifested that MBC and SBR were stimulated at 50 and 100 mg.kg(-1) of Ni but inhibited by further increasing Ni level, showing a Hormesis effect. Earthworm input delayed the occurrence of a maximum SBR inhibition rate under the combined double factors of time and dose. No specific effect of Ni concentration on the qCO(2) was observed. UA was significantly suppressed at 800 mg.kg(-1) Ni (P < 0.05 or 0.01), whereas DHA was more sensitive and significantly inhibited throughout all the treatments (P < 0.01), indicating a pronounced dose-response relationship. The addition of earthworm facilitated all the biomarkers above. The time-dependent of dose-effect relationship (TDR) on MBC and SBR inhibition rates suggested that the peak responsiveness of microorganisms to Ni stress were approximate on the 21st day. The bioavailable form of per unit Ni concentration declined with time expanded and concentration increased, and the changeable process of the relative amount of bioavailability was mainly controlled by a physicochemical reactions. (C) 2017 Elsevier Ltd. All rights reserved.