Dear Editor,Urea is a vital nitrogen(N)fertilizer in farmland soils and the natural intermediate product of various organonitrogen compounds,such as purines and amino acids(Mobley and Hausinger,1989;Glibert et al.,201...Dear Editor,Urea is a vital nitrogen(N)fertilizer in farmland soils and the natural intermediate product of various organonitrogen compounds,such as purines and amino acids(Mobley and Hausinger,1989;Glibert et al.,2014).Urea in soils is rapidly hydrolyzed to ammonium by urease secreted from ureolytic microorganisms,and then assimilated by plants and microbes or involved in other N cycling pathways,including aerobic and anaerobic ammoxidation(Mobley et al.,1995;Pajares and Bohannan,2016).展开更多
To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyse...To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria（PGPB）. It shows that： Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF（Cation Diffusion Facilitator）, Hup E/Ure J and CHR（chromate ion transporter） family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative Cop A/Cue O system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while Znt A transporter, assisted with putative Czc D, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid（IAA） secretion,indicating a potential in-site phytoremediation usage in the mining tailing regions of China.展开更多
Soil abundant taxa diversity positively related to multifunctionality under Hg stress.•Microbial network complexity of soil abundant taxa supported the strength of SBF.•Stochastic assembly of soil abundant subcommunit...Soil abundant taxa diversity positively related to multifunctionality under Hg stress.•Microbial network complexity of soil abundant taxa supported the strength of SBF.•Stochastic assembly of soil abundant subcommunity supported the strength of SBF.•Stochastic ratio was the most important predictor for the strength of SBF.It is known that soil microbial communities are intricately linked to multiple ecosystem functions and can maintain the relationship between soil biodiversity and multifunctionality(SBF)under environmental stresses.However,the relative contributions and driving forces of abundant and rare taxa within the communities in maintaining soil biodiversity-multifunctionality relationship under pollution stresses are still unclear.Here,we conducted microcosm experiments to estimate the importance of soil abundant and rare taxa in predicting these relationships under heavy metal mercury(Hg)stress in paired paddy and upland fields.The results revealed that the diversity of abundant taxa,rather than rare taxa,was positively related to multifunctionality,with the abundant subcommunity tending to maintain a larger proportion of soil functions including chitin degradation,protein degradation,and phosphorus mineralization.Soil multitrophic network complexity consisting of abundant species showed positive correlations with biodiversity and multifunctionality,and supported the strength of SBF within a network complexity range.Stochastic assembly processes of the abundant subcommunity were positively correlated with the strength of SBF,although stochastic processes decreased the biodiversity and the multifunctionality,respectively.After simultaneously accounting for multiple factors on the strength of SBF,we found that the stochastic community assembly ratio of abundant taxa was the most important predictor for SBF strength under Hg stress.Our results highlight the importance of abundant taxa in supporting soil multifunctionality,and elucidate the linkages between community assembly,network complexity and SBF relationship under environmental stresses.展开更多
基金supported by the Funds for International Cooperation and Exchange of the National Natural Science Foundation of China(No.42020104003)。
文摘Dear Editor,Urea is a vital nitrogen(N)fertilizer in farmland soils and the natural intermediate product of various organonitrogen compounds,such as purines and amino acids(Mobley and Hausinger,1989;Glibert et al.,2014).Urea in soils is rapidly hydrolyzed to ammonium by urease secreted from ureolytic microorganisms,and then assimilated by plants and microbes or involved in other N cycling pathways,including aerobic and anaerobic ammoxidation(Mobley et al.,1995;Pajares and Bohannan,2016).
基金supported by the National High Technology Research and Development Program (863) of China (No.2012AA101402)the National Science Foundation of China (Nos.31125007,31370142)
文摘To better understand the diversity of metal resistance genetic determinant from microbes that survived at metal tailings in northwest of China, a highly elevated level of heavy metal containing region, genomic analyses was conducted using genome sequence of three native metal-resistant plant growth promoting bacteria（PGPB）. It shows that： Mesorhizobium amorphae CCNWGS0123 contains metal transporters from P-type ATPase, CDF（Cation Diffusion Facilitator）, Hup E/Ure J and CHR（chromate ion transporter） family involved in copper, zinc, nickel as well as chromate resistance and homeostasis. Meanwhile, the putative Cop A/Cue O system is expected to mediate copper resistance in Sinorhizobium meliloti CCNWSX0020 while Znt A transporter, assisted with putative Czc D, determines zinc tolerance in Agrobacterium tumefaciens CCNWGS0286. The greenhouse experiment provides the consistent evidence of the plant growth promoting effects of these microbes on their hosts by nitrogen fixation and/or indoleacetic acid（IAA） secretion,indicating a potential in-site phytoremediation usage in the mining tailing regions of China.
基金financially supported by the National Natural Science Foundation of China(42177022 and 41877120)Natural Science Foundation of Hubei Province,China(2020CFA013).
文摘Soil abundant taxa diversity positively related to multifunctionality under Hg stress.•Microbial network complexity of soil abundant taxa supported the strength of SBF.•Stochastic assembly of soil abundant subcommunity supported the strength of SBF.•Stochastic ratio was the most important predictor for the strength of SBF.It is known that soil microbial communities are intricately linked to multiple ecosystem functions and can maintain the relationship between soil biodiversity and multifunctionality(SBF)under environmental stresses.However,the relative contributions and driving forces of abundant and rare taxa within the communities in maintaining soil biodiversity-multifunctionality relationship under pollution stresses are still unclear.Here,we conducted microcosm experiments to estimate the importance of soil abundant and rare taxa in predicting these relationships under heavy metal mercury(Hg)stress in paired paddy and upland fields.The results revealed that the diversity of abundant taxa,rather than rare taxa,was positively related to multifunctionality,with the abundant subcommunity tending to maintain a larger proportion of soil functions including chitin degradation,protein degradation,and phosphorus mineralization.Soil multitrophic network complexity consisting of abundant species showed positive correlations with biodiversity and multifunctionality,and supported the strength of SBF within a network complexity range.Stochastic assembly processes of the abundant subcommunity were positively correlated with the strength of SBF,although stochastic processes decreased the biodiversity and the multifunctionality,respectively.After simultaneously accounting for multiple factors on the strength of SBF,we found that the stochastic community assembly ratio of abundant taxa was the most important predictor for SBF strength under Hg stress.Our results highlight the importance of abundant taxa in supporting soil multifunctionality,and elucidate the linkages between community assembly,network complexity and SBF relationship under environmental stresses.
