The addition of simple substrates could affect the microbial respiration in soils. This substrate-induced respiration is widely used to estimate the soil microbial biomass, but little attention has been paid to its in...The addition of simple substrates could affect the microbial respiration in soils. This substrate-induced respiration is widely used to estimate the soil microbial biomass, but little attention has been paid to its influence on the changes of community-level physiological profiles. In this study, the process of microbial communities responding to the added substrate using sole-carbon-source utilization (BIOLOG) was investigated. BIOLOG is biased toward fast-growing bacteria; this advantage was taken to detect the prompt response of the active microbial communities to the added substrate. Four soil samples from agricultural fields adjacent to heavy metal mines were amended with L-arginine, citric acid, or D-glucose. Substrate amendments could, generally, not only increase the metabolic activity of the microbial communities, but also change the metabolic diverse patterns compared with no-substrate control. By tracking the process, it was found that the variance between substrate-induced treatment and control fluctuated greatly during the incubation course, and the influences of these three substrates were different. In addition, the application of these induced changes to discriminate soil microbial communities was tested. The distance among all samples was greatly increased, which further showed the functional variance among microbial communities in soils. This can be very useful in the discrimination of microbial communities even with high similarity.展开更多
In the present work, bacterial soil communities of different grapevine exploitation samples are studied in order to elucidate the possible influence of different agrarian management techniques (use of fertilizers, ir...In the present work, bacterial soil communities of different grapevine exploitation samples are studied in order to elucidate the possible influence of different agrarian management techniques (use of fertilizers, irrigation with river water) may have on the rhizospheric microbiome of Vitis vinifera plants. Therefore, it is postulated the Cenophenoresistome as a novel methodology to evaluate complex communities' global resistance against different antibiotics, by using and adjusting a serial of techniques traditionally applied to evaluate a monospecific population's resistance against antibiotics (Vitek, ATB and disk diffusion methods). Likewise, the metabolic profile (CLPP: comunity level physiological profile) of bacterial communities is studied by Biolog ECO. In relation to the functional structure of the bacterial communities, it is observed that the metabolic profile (diversity, kinetics and CLPP) of unexploited soils differs from soils under anthropic influence. It is discussed the causes of resistance in the human clinic antibiotic treatment based on the agrarian management, especially with the contamination transmitted by irrigation water, which could be associated with changes in edaphic communities. The results obtained in the present study through two different approaches (Cenophenoresistome and metabolic profiles) are consistent with each other, suggesting that both methods can be good bioindicators of the state of humankind-altered soils that host natural ecosystems. Likewise, the concept of Cenophenoresistome is proposed as a bioindicator of soil response to alteration processes, as well as a possible predictor of its evolution in edaphic remediation processes.展开更多
Alpine grasslands with a high soil organic carbon(SOC)storage on the Tibetan Plateau are experiencing rapid climate warming and anthropogenic nitrogen(N)deposition;this is expected to substantially increase the soil N...Alpine grasslands with a high soil organic carbon(SOC)storage on the Tibetan Plateau are experiencing rapid climate warming and anthropogenic nitrogen(N)deposition;this is expected to substantially increase the soil N availability,which may impact carbon(C)cycling.However,little is known regarding how N enrichment influences soil microbial communities and functions relative to C cycling in this region.We conducted a 4-year field experiment on an alpine grassland to evaluate the effects of four different rates of N addition(0,25,50,and 100 kg N ha^-1 year^-1)on the abundance and community structure(phospholipid fatty acids,PLFAs)of microbes,enzyme activities,and community level physiological profiles(CLPP)in soil.We found that N addition increased the microbial biomass C(MBC)and N(MBN),along with an increased abundance of bacterial PLFAs,especially Gram-negative bacterial PLFAs,with a decreasing ratio of Gram-positive to Gram-negative bacteria.The N addition also stimulated the growth of fungi,especially arbuscular mycorrhizal fungi,reducing the ratio of fungi to bacteria.Microbial functional diversity and activity of enzymes involved in C cycling(β-1,4-glucosidase and phenol oxidase)and N cycling(β-1,4-N-acetyl-glucosaminidase and leucine aminopeptidase)increased after N addition,resulting in a loss of SOC.A meta-analysis showed that the soil C/N ratio was a key factor in the response of oxidase activity to N amendment,suggesting that the responses of soil microbial functions,which are linked to C turnover relative to N input,primarily depended upon the soil C/N ratio.Overall,our findings highlight that N addition has a positive influence on microbial communities and their associated functions,which may reduce soil C storage in alpine grasslands under global change scenarios.展开更多
The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last decade.In an attempt to preferably interpret the soil microbiological characteristic...The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last decade.In an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern Guizhou Province,China.The community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial communities.The results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land stage.Similar trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2) decreased with vegetation restoration,and remained at a constantly low level in the arboreal community stage.Analyses of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional diversity.Average utilization of specific substrate guilds was highest in the arboreal community stage.Principle component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three stages.In conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2,thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions.展开更多
基金supported by the National Natural Science Foundation of China(No.30470289,30670039).
文摘The addition of simple substrates could affect the microbial respiration in soils. This substrate-induced respiration is widely used to estimate the soil microbial biomass, but little attention has been paid to its influence on the changes of community-level physiological profiles. In this study, the process of microbial communities responding to the added substrate using sole-carbon-source utilization (BIOLOG) was investigated. BIOLOG is biased toward fast-growing bacteria; this advantage was taken to detect the prompt response of the active microbial communities to the added substrate. Four soil samples from agricultural fields adjacent to heavy metal mines were amended with L-arginine, citric acid, or D-glucose. Substrate amendments could, generally, not only increase the metabolic activity of the microbial communities, but also change the metabolic diverse patterns compared with no-substrate control. By tracking the process, it was found that the variance between substrate-induced treatment and control fluctuated greatly during the incubation course, and the influences of these three substrates were different. In addition, the application of these induced changes to discriminate soil microbial communities was tested. The distance among all samples was greatly increased, which further showed the functional variance among microbial communities in soils. This can be very useful in the discrimination of microbial communities even with high similarity.
文摘In the present work, bacterial soil communities of different grapevine exploitation samples are studied in order to elucidate the possible influence of different agrarian management techniques (use of fertilizers, irrigation with river water) may have on the rhizospheric microbiome of Vitis vinifera plants. Therefore, it is postulated the Cenophenoresistome as a novel methodology to evaluate complex communities' global resistance against different antibiotics, by using and adjusting a serial of techniques traditionally applied to evaluate a monospecific population's resistance against antibiotics (Vitek, ATB and disk diffusion methods). Likewise, the metabolic profile (CLPP: comunity level physiological profile) of bacterial communities is studied by Biolog ECO. In relation to the functional structure of the bacterial communities, it is observed that the metabolic profile (diversity, kinetics and CLPP) of unexploited soils differs from soils under anthropic influence. It is discussed the causes of resistance in the human clinic antibiotic treatment based on the agrarian management, especially with the contamination transmitted by irrigation water, which could be associated with changes in edaphic communities. The results obtained in the present study through two different approaches (Cenophenoresistome and metabolic profiles) are consistent with each other, suggesting that both methods can be good bioindicators of the state of humankind-altered soils that host natural ecosystems. Likewise, the concept of Cenophenoresistome is proposed as a bioindicator of soil response to alteration processes, as well as a possible predictor of its evolution in edaphic remediation processes.
基金supported by the National Program on Key Basic Research Project(No.2014CB954002)the National Natural Science Foundation of China(No.31561143011)。
文摘Alpine grasslands with a high soil organic carbon(SOC)storage on the Tibetan Plateau are experiencing rapid climate warming and anthropogenic nitrogen(N)deposition;this is expected to substantially increase the soil N availability,which may impact carbon(C)cycling.However,little is known regarding how N enrichment influences soil microbial communities and functions relative to C cycling in this region.We conducted a 4-year field experiment on an alpine grassland to evaluate the effects of four different rates of N addition(0,25,50,and 100 kg N ha^-1 year^-1)on the abundance and community structure(phospholipid fatty acids,PLFAs)of microbes,enzyme activities,and community level physiological profiles(CLPP)in soil.We found that N addition increased the microbial biomass C(MBC)and N(MBN),along with an increased abundance of bacterial PLFAs,especially Gram-negative bacterial PLFAs,with a decreasing ratio of Gram-positive to Gram-negative bacteria.The N addition also stimulated the growth of fungi,especially arbuscular mycorrhizal fungi,reducing the ratio of fungi to bacteria.Microbial functional diversity and activity of enzymes involved in C cycling(β-1,4-glucosidase and phenol oxidase)and N cycling(β-1,4-N-acetyl-glucosaminidase and leucine aminopeptidase)increased after N addition,resulting in a loss of SOC.A meta-analysis showed that the soil C/N ratio was a key factor in the response of oxidase activity to N amendment,suggesting that the responses of soil microbial functions,which are linked to C turnover relative to N input,primarily depended upon the soil C/N ratio.Overall,our findings highlight that N addition has a positive influence on microbial communities and their associated functions,which may reduce soil C storage in alpine grasslands under global change scenarios.
基金Supported by the National Basic Research Program (973 Program) of China (No. 2006CB403206)the Key Project in the NationalScience & Technology Pillar Program in the Eleventh Five-year Plan Period of China (Nos. 2006BAC01A09 and 2006BAD03A1006)National Natural Science Foundation of China (No. 30872076)
文摘The mechanism of vegetation restoration on degraded karst regions has been a research focus of soil science and ecology for the last decade.In an attempt to preferably interpret the soil microbiological characteristic variation associated with vegetation restoration and further to explore the role of soil microbiology in vegetation restoration mechanism of degraded karst regions,we measured microbial biomass C and basal respiration in soils during vegetation restoration in Zhenfeng County of southwestern Guizhou Province,China.The community level physiological profiles(CLPP) of the soil microbial community to were estimated determine if vegetation changes were accompanied by changes in functioning of soil microbial communities.The results showed that soil microbial biomass C and microbial quotient(microbial biomass C/organic C) tended to increase with vegetation restoration,being in the order arboreal community stage > shrubby community stage > herbaceous community stage > bare land stage.Similar trend was found in the change of basal respiration(BR).The metabolic quotient(the ratio of basal respiration to microbial biomass,qCO 2) decreased with vegetation restoration,and remained at a constantly low level in the arboreal community stage.Analyses of the CLPP data indicated that vegetation restoration tended to result in higher average well color development,substrate richness,and functional diversity.Average utilization of specific substrate guilds was highest in the arboreal community stage.Principle component analysis of the CLPP data further indicated that the arboreal community stage was distinctly different from the other three stages.In conclusion,vegetation restoration improved soil microbial biomass C,respiration,and utilization of carbon sources,and decreased qCO 2,thus creating better soil conditions,which in turn could promote the restoration of vegetation on degraded karst regions.