Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of pl...Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of plantings on soil microbial diversity.The results showed that the overall effect of afforestation on soil microbial diversity was positive across the country.Random forest algorithm suggested that soil carbon was the most important factor regulating microbial diversity and the positive response was only found with new plantings on low-carbon bare lands but not on high-carbon farmlands and grasslands.In addition,afforestation with broadleaved species increased microbial diversity,whereas planting with conifers had no effect on microbial diversity.This study clarified the effects of plantings on soil microbial diversity,which has an important implication for establishing appropriate policies and practices to improve the multiple functionalities(e.g.,biodiversity conservation and climate change mitigation)during plantation establishment.展开更多
BACKGROUND: The study aims to investigate the performance of a metagenomic next-generationsequencing (NGS)-based diagnostic technique for the identifi cation of potential bacterial and viral infectionsand eff ects of ...BACKGROUND: The study aims to investigate the performance of a metagenomic next-generationsequencing (NGS)-based diagnostic technique for the identifi cation of potential bacterial and viral infectionsand eff ects of concomitant viral infection on the survival rate of intensive care unit (ICU) sepsis patients.METHODS: A total of 74 ICU patients with sepsis who were admitted to our institution from February1, 2018 to June 30, 2019 were enrolled. Separate blood samples were collected from patients for bloodcultures and metagenomic NGS when the patients’ body temperature was higher than 38 °C. Patients’demographic data, including gender, age, ICU duration, ICU scores, and laboratory results, were recorded.The correlations between pathogen types and sepsis severity and survival rate were evaluated.RESULTS: NGS produced higher positive results (105 of 118;88.98%) than blood cultures(18 of 118;15.25%) over the whole study period. Concomitant viral infection correlated closelywith sepsis severity and had the negative effect on the survival of patients with sepsis. However,correlation analysis indicated that the bacterial variety did not correlate with the severity of sepsis.CONCLUSIONS: Concurrent viral load correlates closely with the severity of sepsis and thesurvival rate of the ICU sepsis patients. This suggests that prophylactic administration of antiviraldrugs combined with antibiotics may be benefi cial to ICU sepsis patients.展开更多
The dynamic changes in microbial diversity during the aerobic composting of agricultural crop straw with additives were evaluated using high-throughput sequencing at four phases of composting(mesophilic,thermophilic,c...The dynamic changes in microbial diversity during the aerobic composting of agricultural crop straw with additives were evaluated using high-throughput sequencing at four phases of composting(mesophilic,thermophilic,cooling and maturation phases).In addition,the physicochemical parameters of the composting system were determined in this study.The fermentation time of the thermophilic period was prolonged with the addition of urea or urea combined with a microbial agent.The ratio of C/N and germination index variation indicated that the additives were favorable for composting,because the additives directly changed the physicochemical properties of the compost and had effects on the diversity and abundance of bacteria and fungi.The abundance of operational taxonomic units(OTUs),diversity index(Shannon)and richness index(Chao1)of fungi and bacteria were found to significantly increase when urea+microbial agents were added to straw in the thermophilic phase.The relative abundance of the predominant bacteria and fungi at the phylum and genus levels differed during different composting phases.The abundance of the phyla Firmicutes and Proteobacteria declined in the order of treatments SNW>SN>S(S is straw only compost;SN is straw+5 kg t^(–1) urea compost;and SNW is straw+5 kg t^(–1) urea+1 kg t^(–1) microbial agent compost)in the thermophilic phase.The abundance of the genera Staphylococcus,Bacillus and Thermobifida followed the same order in the mesophilic phase.Ascomycota accounted for more than 92%of the total fungal sequences.With the progression of the composting process,the abundance of Ascomycota decreased gradually.The abundance of Ascomycota followed the order of S>SN>SNW during the thermophilic phase.The abundance of Aspergillus accounted for 4–59%of the total abundance of fungi and increased during the first two sampling periods.Aspergillus abundance followed the order of SNW>SN>S.Additionally,principal component analysis(PCA)revealed that the community compositions in the straw and straw+urea treatments were similar,and that the bacterial communities in treatments S,SN and SNW in the mesophilic phase(at day 1)were different from those observed in three other phases(at days 5,11,and19,respectively),while the fungal communities showed only slight variations in their structure in response to changes in the composting process.Canonical correlation analysis(CCA)and redundancy analysis(RDA)showed that total carbon(TC),NO_(3)^(–)-N(NN),electrical conductivity(EC)and p H were highly correlated with community composition.Therefore,this study highlights that the additives are beneficial to straw composting and result in good quality compost.展开更多
Saline lakes represent a particularly interesting aquatic environment for harboring high microbial diversity.However,the microbial diversity in different states and locations of saline lake is often overlooked.We stud...Saline lakes represent a particularly interesting aquatic environment for harboring high microbial diversity.However,the microbial diversity in different states and locations of saline lake is often overlooked.We studied for the first time the diversity and relative composition of the microbial communities in the Chagan Lake,NE China,and investigated the dif ferences in microbial species and physical and chemical factors in different geographical localities of the lake.After extracting the total DNA of the sample,we tested the library with the established library,sequenced the qualified library with Illumina HiSeq 2500,and studied the bacterial diversity by 16 S rRNA targeted metagenomics analysis.Results reveal that the highest microbial abundance in Chagan Lake at genus level was Proteobacterium followed by Actinomycetes and Bacteroides.In addition,we compared the microbial composition within the lake using alpha-and beta-diversity indices,showing that both diversity and evenness were the highest in the middle of the lake and lowest in the west of lake areas,and in the upper,middle,and lower depth of water columns,the low water column had the highest species number in the whole water environment,but the dif ference was not significant.We believe that physicochemical factors contribute to the formation of microbial community composition and diversity.In aquaculture industry,it is impossible apply horticulture for making full use of the spatial dif ferences in the microbial composition of the water.Therefore,combining cultured aquatic animal with the most suitable microbial species is a good way to boost the breeding ef fect for greater economic value.展开更多
Fumigation is a widely applied approach to mitigate the soil-borne diseases.However,the potential effects of currently applied fumigants on ammonification remain unclear.An 84-day incubation experiment was conducted b...Fumigation is a widely applied approach to mitigate the soil-borne diseases.However,the potential effects of currently applied fumigants on ammonification remain unclear.An 84-day incubation experiment was conducted based on non-fumigated soil(CK)and fumigated soil using three common fumigants,i.e.,chloropicrin(CP),1,3-dichloropropene(1,3-D),and metam sodium(MS).The results showed that,the three fumigants all decreased the microbial C,and the largest reduction(84.7%)occurred with the application of CP.After fumigation,the microbial diversity in the CP treatment rapidly recovered,but that in the 1,3-D treatment decreased and did not recover by the end of the experiment.The application of MS showed no impact on the microbial diversity during the assay,indicating that significantly different microbial diversity can be achieved by choosing different fumigants.Futhermore,the three fumigants showed divergent effects on the enzymes involved in ammonification.The analysis showed that the enzyme variation with CP application was mainly associated with the changed microbial C and N(P<0.05),and not with the microbial community,which was different from the observed effects of 1,3-D or MS application.In addition,the soil quality index showed that CP was still significantly harmful at the end of incubation compared with the good resilience of MS,indicating that CP may not be a suitable fumigant.展开更多
Rural domestic reclaimed water(RDRW)is rural domestic sewage that being safely treated,the irrigation and reuse of RDRW are an effective way to alleviate the contradiction between supply and demand of water resources ...Rural domestic reclaimed water(RDRW)is rural domestic sewage that being safely treated,the irrigation and reuse of RDRW are an effective way to alleviate the contradiction between supply and demand of water resources in South China.In this study,four kinds of irrigation water sources(primary and secondary treated water R1 and R2,purified water R3 and river water CK)and three kinds of water level regulations(low,medium,and high field water level control of W1,W2 and W3)were set to study the impact of RDRW on soil and crop safety,water and nitrogen utilization and biodiversity for establishing the regulation mechanism of RDRW irrigation with field experiment,and monitoring was carried out in RDRW irrigation demonstration area to assess the effectiveness of RDRW.The results showed that,under RDRW irrigation,the contents of Cd and Pb increased slightly,while the contents of Cr,Cu and Zn decreased in paddy soil.The heavy metals content decreased along the direction of stem,leaf and grain in rice plants,but did not increase significantly in rice grains.With the increase of field water level,pharmaceutical and personal care products(PPCPs)content in 60-80 cm soil layer was accumulated,and the PPCPs content in rice husks was higher than that in grains,but it was at a very low level.Compared to CK,RDRW irrigation can effectively increase rice yield,rainwater use efficiency(RUE)and nitrogen use efficiency(NUE)by 5.4%-7.6%,6.7%-9.4%and 21.7%-24.2%,respectively,and the species diversity,community diversity and richness in rice fields were improved.Additionally,water level regulation of W3 with R2 water resource irrigation was conducive to the exertion of comprehensive benefits.The monitoring of demonstration area showed that the consumption of fresh water was reduced by 530 mm,yield was increased by 9.6%,and the soil and crop were both safety.Short-term irrigation of RDRW did not cause soil and crops pollution,however,it is still necessary to track and monitor the effect of the system on soil,crop,and underground water with long-term reclaimed water irrigation.展开更多
Agroecosystems in the Senegalese groundnut basin experience long periods of high temperatures and drought, which disrupt the stability of soil microbial communities. This study evaluated how that stability is affected...Agroecosystems in the Senegalese groundnut basin experience long periods of high temperatures and drought, which disrupt the stability of soil microbial communities. This study evaluated how that stability is affected by homefields and outfields’ agricultural practices and the duration of heat stress. Specifically, we collected soils from organically farmed fields that receive continual high inputs of manure (homefields), and from fields that are rarely manured (outfields). Soil samples were submitted to artificial heat stress at 60°C for 3, 14, and 28 days, followed by 28 days of recovery at 28°C. We examined the functional stability of microbial communities by quantifying C mineralization, and characterized the stability of the communities’ taxonomic compositions via high-throughput DNA sequencing. We found that the microbial communities have a low resistance to heat stress in soils from both types of fields. However, the manuring practice does affect how the functional stability of microbial communities responds to different durations of heat stress. Although functional stability was not recovered fully in either soil, microbial community resilience seemed to be greater in homefield soils. Differences in manuring practices also affected the structural taxonomic stability of microbial communities: relative abundances of Bacilli, Chloroflexia, Actinobacteria and Sordariomycetes increased in the homefield stressed-soils, but decreased significantly in outfield soils. In contrast, relative abundances of α-Proteobacteria, γ-Proteobacteria and Eurotiomycetes increased significantly in outfield stressed-soils, while decreasing significantly in the homefield soils. Relative abundances of Bacilli changed little in outfield soils, indicating that this taxon is resistant to heat stress. In summary, the microbial communities’ capacities to resist heat stress and recover from it depend upon the organic richness of the soil (i.e., manuring practice) and the adaptation of soil microbes to environmental conditions.展开更多
The soil microorganisms at different depths play an important role in soil formation,ecosystem biogeochemistry,recycling of nutrients,and degradation of waste products.The aims of this study were to observe the microb...The soil microorganisms at different depths play an important role in soil formation,ecosystem biogeochemistry,recycling of nutrients,and degradation of waste products.The aims of this study were to observe the microbial diversity in the profile of an agricultural soil in northern China,and to research the correlation between soil microbes and geochemistry.First,the soil geochemistry of the profile was investigated through 25 chemical elements.Secondly,the various physiological groups of microorganisms w...展开更多
Biochar is a widely known soil amendment.Here we synthesize the available information on influence of biochar application on different soil properties and crop productivity using meta-analysis.Global data on influence...Biochar is a widely known soil amendment.Here we synthesize the available information on influence of biochar application on different soil properties and crop productivity using meta-analysis.Global data on influence of biochar applications on different soil physical,chemical,microbial properties,and crop productivity were extracted from literature and statistically analyzed.Based on selection criteria,59 studies from the literature published between 2012 and 2021 were selected for the meta-analysis.Correlations were developed between effect size of biochar application on different soil properties and crop productivity.Application of biochar increased soil pH,cation exchange capacity,and organic carbon by 46%,20%,and 27%,respectively,with greater effects in coarse and fine-textured soils.Effects on chemical properties were variable among biochar prepared from different feedstocks.Among physical properties,biochar application reduced bulk densities by 29%and increased porosity by 59%.Biochar prepared at higher pyrolytic temperatures(>500℃)improved bulk density and porosity to greater extents(31%and 66%,respectively).Biochar prepared at lower pyrolytic temperatures(<500℃)had a greater effect on microbial diversity(both bacterial and fungal),with more diverse bacterial populations in medium and coarse textured soils,while fungal diversity increased in fine textured soils.Biochar applications increased crop productivity only in fine and coarse textured soil.The effect size of biochar application on crop productivity was correlated with responses to physical properties of soils.The meta-analysis highlighted the need to conduct long-term field experiments to provide better explanations for changes in biochar properties as it undergoes aging,its longer-term effects on soil properties,and timing of re-application of different biochars.展开更多
Microbial populations in the gastrointestinal tract contribute to host health and nutrition.Although gut microbial ecology is well studied in livestock and domestic animals,little is known of the endogenous population...Microbial populations in the gastrointestinal tract contribute to host health and nutrition.Although gut microbial ecology is well studied in livestock and domestic animals,little is known of the endogenous populations inhabiting primates or carnivora.We characterized microbial populations in fecal cultures from gorillas(Gorilla gorilla gorilla),common chimpanzees(Pan troglodytes),Hamadryas baboons(Papio hamadryas)and binturongs(Arctictis binturong)to compare the microbiomes associated with different gastrointestinal morphologies and different omnivorous feeding strategies.Each species was fed a distinct standardized diet for 2 weeks prior to fecal collection.All diets were formulated to reflect the species’feeding strategies in situ.Fresh fecal samples were pooled within species and used to inoculate in vitro batch cultures.Acetate,propionate,butyrate and valerate were measured after 24 h of incubation.Eubacterial DNA was extracted from individual fecal samples,pooled,and the cpn60 gene region was amplified and then sequenced to identify the major eubacterial constituents associated with each host species.Short chain fatty acids(P<0.001)and methane(P<0.001)were significantly different across species.Eubacterial profiles were consistent with fermentation data and suggest an increase in diversity with dietary fiber.展开更多
Information on the gut microbiome composition of different mammals could provide novel insights into the evolution of mammals and succession of microbial communities in different hosts.However,there is limited informa...Information on the gut microbiome composition of different mammals could provide novel insights into the evolution of mammals and succession of microbial communities in different hosts.However,there is limited information on the gut microbiome composition of marine mammals,especially cetaceans because of sampling constraints.In this study,we investigated the diversity and composition of microbial communities in the stomach,midgut,and hindgut of 2 stranded short-finned pilot whales(Globicephala macrorhynchus)and hindgut of a stranded pygmy sperm whale(Kogia breviceps)by using 16S rRNA gene amplicon sequencing technology.On the basis of the 50 most abundant operational taxonomic units,principal coordinate analysis,and non-metric multidimensional scaling analysis,we confirmed that the gut microbial communities of the 3 whales were different.Our results revealed that the gut microbiome of 1 stranded short-finned pilot whale GM16 was dominated by Firmicutes(mainly Clostridium)and Fusobacteria;whereas that of the other pilot whale GM19 was composed of Gammaproteobacteria and Bacteroidetes(mainly Vibrio and Bacteroides,respectively),probably caused by intestinal disease and antibiotic treatment.The gut microbiome of the pygmy sperm whale was dominated by Firmicutes and Bacteroidetes.Moreover,different gastrointestinal tract regions harbored different microbial community structures.To our knowledge,this is the first report of the gut microbiome of short-finned pilot whales,and our findings will expand our current knowledge on microbial diversity and composition in the gastrointestinal tract of cetaceans.展开更多
This study assessed the performance and diversity of microbial communities in multi-stage sub-surface flow constructed wetland systems(CWs). Our aim was to assess the impact of configuration on treatment performance a...This study assessed the performance and diversity of microbial communities in multi-stage sub-surface flow constructed wetland systems(CWs). Our aim was to assess the impact of configuration on treatment performance and microbial diversity in the systems. Results indicate that at loading rates up to 100 g BOD5/(m2·day), similar treatment performances can be achieved using either a 3 or 4 stage configuration. In the case of phosphorus(P), the impact of configuration was less obvious and a minimum of 80% P removal can be expected for loadings up to 10 g P/(m2·day) based on the performance results obtained within the first16 months of operation. Microbial analysis showed an increased bacterial diversity in stage four compared to the first stage. These results indicate that the design and configuration of multi-stage constructed wetland systems may have an impact on the treatment performance and the composition of the microbial community in the systems, and such knowledge can be used to improve their design and performance.展开更多
Background: Studies had shown many diseases affect the stability of human microbiota, but how this relates to benign prostatic hyperplasia(BPH) has not been well understood. Hence, this study aimed to investigate the ...Background: Studies had shown many diseases affect the stability of human microbiota, but how this relates to benign prostatic hyperplasia(BPH) has not been well understood. Hence, this study aimed to investigate the regulation of BPH on gut microbiota composition and metabonomics.Methods: We analyzed gut samples from rats with BPH and healthy control rats, the gut microbiota composition and metabonomics were detected by 16S rDNA sequencing and liquid chromatography tandem mass spectrometry(LC–MS/MS).Results: High-throughput sequencing results showed that gut microbiota beta-diversity increased(P<0.01) in the BPH group vs. control group. Muribaculaceae(P<0.01), Turicibacteraceae(P<0.05), Turicibacter(P<0.01) and Coprococcus(P<0.01) were significantly decreased in the BPH group, whereas that of Mollicutes(P<0.05) and Prevotella(P<0.05)were significantly increased compared with the control group. Despite profound interindividual variability, the levels of several predominant genera were different. In addition, there were no statistically significant differences in several bacteria. BPH group vs. control group: Firmicutes(52.30% vs. 57.29%, P>0.05), Bacteroidetes(46.54% vs. 41.64%,P>0.05), Clostridia(50.89% vs. 54.66%, P>0.05), Ruminococcaceae(25.67% vs. 20.56%, P>0.05). LC–MS/MS of intestinal contents revealed that differential metabolites were mainly involved in cellular processes, environmental information processing, metabolism and organismal systems. The most important pathways were global and overview maps, lipid metabolism, amino acid metabolism, digestive system and endocrine system. Through enrichment analysis, we found that the differential metabolites were significantly enriched in metabolic pathways, steroid hormone biosynthesis,ovarian steroidogenesis, biosynthesis of unsaturated fatty acids and bile secretion. Pearson correlation analysis(R=0.94) showed that there was a strong correlation between Prevotellaceae, Corynebacteriaceae, Turicibacteraceae,Bifidobacteriaceae and differential metabolites.Conclusions: Our findings suggested an association between the gut microbiota and BPH, but the causal relationship between the two groups is unclear. Thus, further studies are warranted to elucidate the potential mechanisms and causal relationships between BPH and gut microbiota.展开更多
The Southwest Indian Ridge,which is the slowest-spreading of the main ridges,separates the African and Antarctic plates.The slow expanding rate is associated with less density of hydrothermal vent fields,shorter longe...The Southwest Indian Ridge,which is the slowest-spreading of the main ridges,separates the African and Antarctic plates.The slow expanding rate is associated with less density of hydrothermal vent fields,shorter longevity of hydrothermal activity,cold mantle temperatures and thick lithosphere.However,the microbial communities adapting to such specific characteristics of this area have remained largely unexplored.To study the microbial diversity at the Southwest Indian Ridge,we sampled three sediment cores in a newly found inactive vent field,the Tianzuo field,and used high-throughput sequencing of 16S rRNA genes to reveal the microbial composition.Microbial communities of three sampling sites were very similar at the surface,and underwent a gradient change along depth.Gammaproteobacteria,namely Alteromonadaceae,Nitrosococcus and the JTB255 marine benthic group,were the most dominant bacterial taxa.Marine Group I was the dominant archaeal taxon in our samples.In addition,microbial populations capable of ammonia oxidation,nitrite oxidation,sulfur oxidation and manganese oxidation were detected to be the main chemolithoautotrophs.The enrichment of sulfur-oxidizing and manganese-oxidizing bacteria was observed in deep layers.When compared with other vent fields along different ocean ridges,the Tianzuo field showed distinct composition in both archaeal and bacterial communities.These results provide the first view of microbial communities of the Tianzuo field at the Southwest Indian Ridge,and give a better understanding of metabolic potential possessed by the microbial populations.展开更多
Robinia pseudoacacia L.(RP)restoration has increased vegetation cover in semi-arid regions on the Loess Plateau of China,but ecological problems have also occurred due to RP restoration,such as reduced soil moisture.F...Robinia pseudoacacia L.(RP)restoration has increased vegetation cover in semi-arid regions on the Loess Plateau of China,but ecological problems have also occurred due to RP restoration,such as reduced soil moisture.Further,it is still uncertain how microbial diversity,composition and assembly processes change with RP restoration in semi-arid regions.Therefore,amplicon sequencing of small subunit ribosomal ribonucleic acid(16S rRNA)and internal transcribed spacer(ITS)genes was performed to study soil bacterial and fungal diversity,composition and assembly processes at four study sites with different stand ages of RP plantations(Y10,RP plantation with stand ages less than 10 a;Y15,RP plantation with stand ages approximately 15 a;Y25,RP plantation with stand ages approximately 25 a;and Y40,RP plantation with stand ages approximately 40 a)along a 40-a chronosequence on the Loess Plateau.The diversity of soil bacteria and fungi increased significantly during the restoration period from 10 to 15 a(P<0.05).However,compared with Y15,bacterial diversity was lower at Y25 and Y40,and fungal diversity remained stable during the restoration period between 25 and 40 a.The relative abundances of Proteobacteria and Ascomycota increased during the restoration period from 10 to 15 a.Conversely,after 15 a of restoration,they both decreased,whereas the relative abundances of Actinomycetes,Acidobacteria and Basidiomycota gradually increased.The variations in soil bacterial communities were mainly related to changes in soil total nitrogen,nitrate nitrogen and moisture contents,while soil fungal communities were mainly shaped by soil organic carbon and nitrate nitrogen contents.Bacterial communities were structured by the heterogeneous selection and stochastic process,while fungal communities were structured primarily by the stochastic process.The RP restoration induced an increase in the relative importance of heterogeneous selection on bacterial communities.Overall,this study reveals the changes in microbial diversity,community composition and assembly processes with RP restoration on the Loess Plateau and provides a new perspective on the effects of vegetation restoration on soil microbial communities in semi-arid regions.展开更多
In this study,PCR-denaturing gradient gel electrophoresis(DGGE)was applied to analyze the microbial communities in lake sediments from Lake Xuanwu,Lake Mochou in Nanjing and Lake Taihu in Wuxi.Sediment samples from se...In this study,PCR-denaturing gradient gel electrophoresis(DGGE)was applied to analyze the microbial communities in lake sediments from Lake Xuanwu,Lake Mochou in Nanjing and Lake Taihu in Wuxi.Sediment samples from seven locations in three lakes were collected and their genomic DNAs were extracted.The DNA yields of the sediments of Lake Xuanwu and Lake Mochou were high(10 mg/g),while that of sediments in Lake Taihu was relatively low.After DNA purification,the 16S rDNA genes(V3 to V5 region)were amplified and the amplified DNA fragments were separated by parallel DGGE.The DGGE profiles showed that there were five common bands in all the lake sediment samples indicating that there were similarities among the populations of microorganisms in all the lake sediments.The DGGE profiles of Lake Xuanwu and Lake Mochou were similar and about 20 types of micro-organisms were identified in the sediment samples of both lakes.These results suggest that the sediment samples of these two city lakes(Xuanwu,Mochou)have similar microbial communities.However,the DGGE profiles of sediment samples in Lake Taihu were significantly different from these two lakes.Furthermore,the DGGE profiles of sediment samples in different locations in Lake Taihu were also different,suggesting that the microbial communities in Lake Taihu are more diversified than those in Lake Xuanwu and Lake Mochou.The differences in microbial diversity may be caused by the different environmental conditions,such as redox potential,pH,and the concentrations of organic matters.Seven major bands of 16S rDNA genes fragments from the DGGE profiles of sediment samples were further reamplified and sequenced.The results of sequencing analysis indicate that five sequences shared 99%-100%homology with known sequences(Bacillus and Brevibacillus,uncultured bacteria),while the other two sequences shared 93%-96%homology with known sequences(Acinetobacter,and Bacillus).The study shows that the PCR-DGGE technique combined with sequence analysis is a feasible and efficient method for the determination of microbial communities in sediment samples.展开更多
Timely removal of the flower is a key agricultural measure to ensure the concentrated supply of nutrients for the growth of underground bulbs and to increase the yield of lilies. Removing flowers and returning them to...Timely removal of the flower is a key agricultural measure to ensure the concentrated supply of nutrients for the growth of underground bulbs and to increase the yield of lilies. Removing flowers and returning them to the field is one of the tradi‐tional ways of treatment, and field litter is formed at this time. Previous study showed that the decomposition of litter changes the soil properties. In order to study the effects of lily litter decomposition on soil physical and chemical proper‐ties and microbial structure, three treatments were set up in reference to the Decomposition Bag Method: control (CK), Lanzhou lily flower treatment (LZF), and Zhongbai No.1 flower treatment (ZBF). The effects of lily decomposition on soil physical and chemical properties and microbial community composition were studied in order to provide a scientific basis and theoretical guidance for the planting process of Lanzhou lily. The results show that the decomposition of lily flowers significantly increased the contents of soil organic matter, soil total nitrogen, soil total phosphorus and soil avail‐able potassium, and decreased soil pH. RDA shows that soil available nutrients and pH were the driving factors for the change of the soil microbial community. A short-term change of soil microenvironment caused by the decomposed lily flower is beneficial to growing the Lanzhou lily. However, under the correlation analysis of environmental factors, the long-term effects of returning the Lanzhou lily flower to the field, such as the trend of soil acidification, need to be further studied.展开更多
Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determi...Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains uncertain.In this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical forests.The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality.Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity.Stand structure-played an important role in modulating the effects of tree diversity on multifunctionality.The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.展开更多
Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In...Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In order to provide a basis for the prevention and treatment of peony powdery mildew,we examined the microbial diversity,the malondialdehyde(MDA)concentrations and antioxidant enzyme activities of peony leaves infected with three levels of powdery mildew to determine any modifications to the leaf's antioxidant enzyme systems and microbial community structure following the onset of disease.The results show that the MDA content rose as the degree of infection became worse.Antioxidant enzyme activity rose and then declined.Following the initiation of powdery mildew,fungal community diversity decreased,whereas there was not any appreciable change in bacterial communities according to microbial diversity sequencing.The relative abundance of more than half of fungal species decreased,with the bacterial genera displaying both abundant and diminished communities with less pronounced alterations in their community structure after the disease spread.Significant different taxa that were critical to the organization of each microbiome were found.Correlation analysis showed that the relative abundance of powdery mildew pathogenic fungal genus Erysiphe was correlated with those of 11 fungal genera and one bacterial genus.Among them,Aureobasidium,Neosetophoma and Sclerostagonospora showed significant positive correlations with Erysiphe and MDA.展开更多
The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chrom...The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.展开更多
基金supported by the National Key Research and Development Program of China(2021YFD2200401)the National Natural Science Foundation of China(31901293)。
文摘Afforestation has an important role in biodiversity conservation and ecosystem function improvement.A meta-analysis was carried out in China,which has the largest plantation area globally,to quantify the effects of plantings on soil microbial diversity.The results showed that the overall effect of afforestation on soil microbial diversity was positive across the country.Random forest algorithm suggested that soil carbon was the most important factor regulating microbial diversity and the positive response was only found with new plantings on low-carbon bare lands but not on high-carbon farmlands and grasslands.In addition,afforestation with broadleaved species increased microbial diversity,whereas planting with conifers had no effect on microbial diversity.This study clarified the effects of plantings on soil microbial diversity,which has an important implication for establishing appropriate policies and practices to improve the multiple functionalities(e.g.,biodiversity conservation and climate change mitigation)during plantation establishment.
基金supported by grants from Scienceand Technology Committee of Shanghai (18411951400)KeyClinical Medical Specialties Project in Shanghai Pudong NewArea (PWZzk2017-22)+1 种基金Science and Technology Action Plan(19495810200)Leading Talent Project in Shanghai Pudong NewArea Health System (PWRl2018-08).
文摘BACKGROUND: The study aims to investigate the performance of a metagenomic next-generationsequencing (NGS)-based diagnostic technique for the identifi cation of potential bacterial and viral infectionsand eff ects of concomitant viral infection on the survival rate of intensive care unit (ICU) sepsis patients.METHODS: A total of 74 ICU patients with sepsis who were admitted to our institution from February1, 2018 to June 30, 2019 were enrolled. Separate blood samples were collected from patients for bloodcultures and metagenomic NGS when the patients’ body temperature was higher than 38 °C. Patients’demographic data, including gender, age, ICU duration, ICU scores, and laboratory results, were recorded.The correlations between pathogen types and sepsis severity and survival rate were evaluated.RESULTS: NGS produced higher positive results (105 of 118;88.98%) than blood cultures(18 of 118;15.25%) over the whole study period. Concomitant viral infection correlated closelywith sepsis severity and had the negative effect on the survival of patients with sepsis. However,correlation analysis indicated that the bacterial variety did not correlate with the severity of sepsis.CONCLUSIONS: Concurrent viral load correlates closely with the severity of sepsis and thesurvival rate of the ICU sepsis patients. This suggests that prophylactic administration of antiviraldrugs combined with antibiotics may be benefi cial to ICU sepsis patients.
基金the National Key R&D Program of China(2017YFD0801304)the National Natural Science Foundation of China(31972943)。
文摘The dynamic changes in microbial diversity during the aerobic composting of agricultural crop straw with additives were evaluated using high-throughput sequencing at four phases of composting(mesophilic,thermophilic,cooling and maturation phases).In addition,the physicochemical parameters of the composting system were determined in this study.The fermentation time of the thermophilic period was prolonged with the addition of urea or urea combined with a microbial agent.The ratio of C/N and germination index variation indicated that the additives were favorable for composting,because the additives directly changed the physicochemical properties of the compost and had effects on the diversity and abundance of bacteria and fungi.The abundance of operational taxonomic units(OTUs),diversity index(Shannon)and richness index(Chao1)of fungi and bacteria were found to significantly increase when urea+microbial agents were added to straw in the thermophilic phase.The relative abundance of the predominant bacteria and fungi at the phylum and genus levels differed during different composting phases.The abundance of the phyla Firmicutes and Proteobacteria declined in the order of treatments SNW>SN>S(S is straw only compost;SN is straw+5 kg t^(–1) urea compost;and SNW is straw+5 kg t^(–1) urea+1 kg t^(–1) microbial agent compost)in the thermophilic phase.The abundance of the genera Staphylococcus,Bacillus and Thermobifida followed the same order in the mesophilic phase.Ascomycota accounted for more than 92%of the total fungal sequences.With the progression of the composting process,the abundance of Ascomycota decreased gradually.The abundance of Ascomycota followed the order of S>SN>SNW during the thermophilic phase.The abundance of Aspergillus accounted for 4–59%of the total abundance of fungi and increased during the first two sampling periods.Aspergillus abundance followed the order of SNW>SN>S.Additionally,principal component analysis(PCA)revealed that the community compositions in the straw and straw+urea treatments were similar,and that the bacterial communities in treatments S,SN and SNW in the mesophilic phase(at day 1)were different from those observed in three other phases(at days 5,11,and19,respectively),while the fungal communities showed only slight variations in their structure in response to changes in the composting process.Canonical correlation analysis(CCA)and redundancy analysis(RDA)showed that total carbon(TC),NO_(3)^(–)-N(NN),electrical conductivity(EC)and p H were highly correlated with community composition.Therefore,this study highlights that the additives are beneficial to straw composting and result in good quality compost.
基金Supported by the National Natural Sciences Foundational of China(No.30972191)the 948 Program from the Ministry of Agriculture of China(No.2014Z34)
文摘Saline lakes represent a particularly interesting aquatic environment for harboring high microbial diversity.However,the microbial diversity in different states and locations of saline lake is often overlooked.We studied for the first time the diversity and relative composition of the microbial communities in the Chagan Lake,NE China,and investigated the dif ferences in microbial species and physical and chemical factors in different geographical localities of the lake.After extracting the total DNA of the sample,we tested the library with the established library,sequenced the qualified library with Illumina HiSeq 2500,and studied the bacterial diversity by 16 S rRNA targeted metagenomics analysis.Results reveal that the highest microbial abundance in Chagan Lake at genus level was Proteobacterium followed by Actinomycetes and Bacteroides.In addition,we compared the microbial composition within the lake using alpha-and beta-diversity indices,showing that both diversity and evenness were the highest in the middle of the lake and lowest in the west of lake areas,and in the upper,middle,and lower depth of water columns,the low water column had the highest species number in the whole water environment,but the dif ference was not significant.We believe that physicochemical factors contribute to the formation of microbial community composition and diversity.In aquaculture industry,it is impossible apply horticulture for making full use of the spatial dif ferences in the microbial composition of the water.Therefore,combining cultured aquatic animal with the most suitable microbial species is a good way to boost the breeding ef fect for greater economic value.
基金Supported by the National Key Research and Development Program of China(2018YFD0300505)the National Key Technologies Project of China in Urban Agriculture during the 12th Five-Year Plan(2014BAD14B03).
文摘Fumigation is a widely applied approach to mitigate the soil-borne diseases.However,the potential effects of currently applied fumigants on ammonification remain unclear.An 84-day incubation experiment was conducted based on non-fumigated soil(CK)and fumigated soil using three common fumigants,i.e.,chloropicrin(CP),1,3-dichloropropene(1,3-D),and metam sodium(MS).The results showed that,the three fumigants all decreased the microbial C,and the largest reduction(84.7%)occurred with the application of CP.After fumigation,the microbial diversity in the CP treatment rapidly recovered,but that in the 1,3-D treatment decreased and did not recover by the end of the experiment.The application of MS showed no impact on the microbial diversity during the assay,indicating that significantly different microbial diversity can be achieved by choosing different fumigants.Futhermore,the three fumigants showed divergent effects on the enzymes involved in ammonification.The analysis showed that the enzyme variation with CP application was mainly associated with the changed microbial C and N(P<0.05),and not with the microbial community,which was different from the observed effects of 1,3-D or MS application.In addition,the soil quality index showed that CP was still significantly harmful at the end of incubation compared with the good resilience of MS,indicating that CP may not be a suitable fumigant.
基金supported by National Key Research and Development Program(2019YFC0408803)Basic Public Welfare Research Project of Zhejiang Province(LGN20E090001)and Water conservancy science and technology in Zhejiang Province(RC1918,RC2029).
文摘Rural domestic reclaimed water(RDRW)is rural domestic sewage that being safely treated,the irrigation and reuse of RDRW are an effective way to alleviate the contradiction between supply and demand of water resources in South China.In this study,four kinds of irrigation water sources(primary and secondary treated water R1 and R2,purified water R3 and river water CK)and three kinds of water level regulations(low,medium,and high field water level control of W1,W2 and W3)were set to study the impact of RDRW on soil and crop safety,water and nitrogen utilization and biodiversity for establishing the regulation mechanism of RDRW irrigation with field experiment,and monitoring was carried out in RDRW irrigation demonstration area to assess the effectiveness of RDRW.The results showed that,under RDRW irrigation,the contents of Cd and Pb increased slightly,while the contents of Cr,Cu and Zn decreased in paddy soil.The heavy metals content decreased along the direction of stem,leaf and grain in rice plants,but did not increase significantly in rice grains.With the increase of field water level,pharmaceutical and personal care products(PPCPs)content in 60-80 cm soil layer was accumulated,and the PPCPs content in rice husks was higher than that in grains,but it was at a very low level.Compared to CK,RDRW irrigation can effectively increase rice yield,rainwater use efficiency(RUE)and nitrogen use efficiency(NUE)by 5.4%-7.6%,6.7%-9.4%and 21.7%-24.2%,respectively,and the species diversity,community diversity and richness in rice fields were improved.Additionally,water level regulation of W3 with R2 water resource irrigation was conducive to the exertion of comprehensive benefits.The monitoring of demonstration area showed that the consumption of fresh water was reduced by 530 mm,yield was increased by 9.6%,and the soil and crop were both safety.Short-term irrigation of RDRW did not cause soil and crops pollution,however,it is still necessary to track and monitor the effect of the system on soil,crop,and underground water with long-term reclaimed water irrigation.
文摘Agroecosystems in the Senegalese groundnut basin experience long periods of high temperatures and drought, which disrupt the stability of soil microbial communities. This study evaluated how that stability is affected by homefields and outfields’ agricultural practices and the duration of heat stress. Specifically, we collected soils from organically farmed fields that receive continual high inputs of manure (homefields), and from fields that are rarely manured (outfields). Soil samples were submitted to artificial heat stress at 60°C for 3, 14, and 28 days, followed by 28 days of recovery at 28°C. We examined the functional stability of microbial communities by quantifying C mineralization, and characterized the stability of the communities’ taxonomic compositions via high-throughput DNA sequencing. We found that the microbial communities have a low resistance to heat stress in soils from both types of fields. However, the manuring practice does affect how the functional stability of microbial communities responds to different durations of heat stress. Although functional stability was not recovered fully in either soil, microbial community resilience seemed to be greater in homefield soils. Differences in manuring practices also affected the structural taxonomic stability of microbial communities: relative abundances of Bacilli, Chloroflexia, Actinobacteria and Sordariomycetes increased in the homefield stressed-soils, but decreased significantly in outfield soils. In contrast, relative abundances of α-Proteobacteria, γ-Proteobacteria and Eurotiomycetes increased significantly in outfield stressed-soils, while decreasing significantly in the homefield soils. Relative abundances of Bacilli changed little in outfield soils, indicating that this taxon is resistant to heat stress. In summary, the microbial communities’ capacities to resist heat stress and recover from it depend upon the organic richness of the soil (i.e., manuring practice) and the adaptation of soil microbes to environmental conditions.
文摘The soil microorganisms at different depths play an important role in soil formation,ecosystem biogeochemistry,recycling of nutrients,and degradation of waste products.The aims of this study were to observe the microbial diversity in the profile of an agricultural soil in northern China,and to research the correlation between soil microbes and geochemistry.First,the soil geochemistry of the profile was investigated through 25 chemical elements.Secondly,the various physiological groups of microorganisms w...
基金a National Institute of Food and Agriculture,United States Department of Agriculture research award(Number 2019-68012-29888)the Sustainable Intensification Innovation Lab funded by the United States Agency for International Development(Grant Number AID-OAA-L-14-00006)+1 种基金funds allocated to the USDA-ARS project 3070-21610-003-00Dthe sole responsibility of authors and do not reflect the views of funding agencies and representing organizations.Contribution No.21-310-J from the Kansas Agricultural Experiment Station.The US Department of Agriculture(USDA)is an equal opportunity employer and provider of services in all its programs and activities.
文摘Biochar is a widely known soil amendment.Here we synthesize the available information on influence of biochar application on different soil properties and crop productivity using meta-analysis.Global data on influence of biochar applications on different soil physical,chemical,microbial properties,and crop productivity were extracted from literature and statistically analyzed.Based on selection criteria,59 studies from the literature published between 2012 and 2021 were selected for the meta-analysis.Correlations were developed between effect size of biochar application on different soil properties and crop productivity.Application of biochar increased soil pH,cation exchange capacity,and organic carbon by 46%,20%,and 27%,respectively,with greater effects in coarse and fine-textured soils.Effects on chemical properties were variable among biochar prepared from different feedstocks.Among physical properties,biochar application reduced bulk densities by 29%and increased porosity by 59%.Biochar prepared at higher pyrolytic temperatures(>500℃)improved bulk density and porosity to greater extents(31%and 66%,respectively).Biochar prepared at lower pyrolytic temperatures(<500℃)had a greater effect on microbial diversity(both bacterial and fungal),with more diverse bacterial populations in medium and coarse textured soils,while fungal diversity increased in fine textured soils.Biochar applications increased crop productivity only in fine and coarse textured soil.The effect size of biochar application on crop productivity was correlated with responses to physical properties of soils.The meta-analysis highlighted the need to conduct long-term field experiments to provide better explanations for changes in biochar properties as it undergoes aging,its longer-term effects on soil properties,and timing of re-application of different biochars.
文摘Microbial populations in the gastrointestinal tract contribute to host health and nutrition.Although gut microbial ecology is well studied in livestock and domestic animals,little is known of the endogenous populations inhabiting primates or carnivora.We characterized microbial populations in fecal cultures from gorillas(Gorilla gorilla gorilla),common chimpanzees(Pan troglodytes),Hamadryas baboons(Papio hamadryas)and binturongs(Arctictis binturong)to compare the microbiomes associated with different gastrointestinal morphologies and different omnivorous feeding strategies.Each species was fed a distinct standardized diet for 2 weeks prior to fecal collection.All diets were formulated to reflect the species’feeding strategies in situ.Fresh fecal samples were pooled within species and used to inoculate in vitro batch cultures.Acetate,propionate,butyrate and valerate were measured after 24 h of incubation.Eubacterial DNA was extracted from individual fecal samples,pooled,and the cpn60 gene region was amplified and then sequenced to identify the major eubacterial constituents associated with each host species.Short chain fatty acids(P<0.001)and methane(P<0.001)were significantly different across species.Eubacterial profiles were consistent with fermentation data and suggest an increase in diversity with dietary fiber.
基金This study was supported by grants from the National Key R&D Program of China(Grant numbers 2017YFC0306702 and 2016YFC0300803)National Natural Science Foundation of China(Grant No.41506139)Youth Innovation Promotion Association of Chinese Academy of Sciences.This study was performed under Ethical Statement number IDSSE-SYLL-MMMBL-01.
文摘Information on the gut microbiome composition of different mammals could provide novel insights into the evolution of mammals and succession of microbial communities in different hosts.However,there is limited information on the gut microbiome composition of marine mammals,especially cetaceans because of sampling constraints.In this study,we investigated the diversity and composition of microbial communities in the stomach,midgut,and hindgut of 2 stranded short-finned pilot whales(Globicephala macrorhynchus)and hindgut of a stranded pygmy sperm whale(Kogia breviceps)by using 16S rRNA gene amplicon sequencing technology.On the basis of the 50 most abundant operational taxonomic units,principal coordinate analysis,and non-metric multidimensional scaling analysis,we confirmed that the gut microbial communities of the 3 whales were different.Our results revealed that the gut microbiome of 1 stranded short-finned pilot whale GM16 was dominated by Firmicutes(mainly Clostridium)and Fusobacteria;whereas that of the other pilot whale GM19 was composed of Gammaproteobacteria and Bacteroidetes(mainly Vibrio and Bacteroides,respectively),probably caused by intestinal disease and antibiotic treatment.The gut microbiome of the pygmy sperm whale was dominated by Firmicutes and Bacteroidetes.Moreover,different gastrointestinal tract regions harbored different microbial community structures.To our knowledge,this is the first report of the gut microbiome of short-finned pilot whales,and our findings will expand our current knowledge on microbial diversity and composition in the gastrointestinal tract of cetaceans.
文摘This study assessed the performance and diversity of microbial communities in multi-stage sub-surface flow constructed wetland systems(CWs). Our aim was to assess the impact of configuration on treatment performance and microbial diversity in the systems. Results indicate that at loading rates up to 100 g BOD5/(m2·day), similar treatment performances can be achieved using either a 3 or 4 stage configuration. In the case of phosphorus(P), the impact of configuration was less obvious and a minimum of 80% P removal can be expected for loadings up to 10 g P/(m2·day) based on the performance results obtained within the first16 months of operation. Microbial analysis showed an increased bacterial diversity in stage four compared to the first stage. These results indicate that the design and configuration of multi-stage constructed wetland systems may have an impact on the treatment performance and the composition of the microbial community in the systems, and such knowledge can be used to improve their design and performance.
基金supported(in part)by the Fundamental Research Funds for the Central Universities(2042021kf1041,2042021kf1041)the Medical Science and Technique Foundation of Henan Province(SBGJ202002097)the National Key Research and Development Plan of China(2016YFC0106300)。
文摘Background: Studies had shown many diseases affect the stability of human microbiota, but how this relates to benign prostatic hyperplasia(BPH) has not been well understood. Hence, this study aimed to investigate the regulation of BPH on gut microbiota composition and metabonomics.Methods: We analyzed gut samples from rats with BPH and healthy control rats, the gut microbiota composition and metabonomics were detected by 16S rDNA sequencing and liquid chromatography tandem mass spectrometry(LC–MS/MS).Results: High-throughput sequencing results showed that gut microbiota beta-diversity increased(P<0.01) in the BPH group vs. control group. Muribaculaceae(P<0.01), Turicibacteraceae(P<0.05), Turicibacter(P<0.01) and Coprococcus(P<0.01) were significantly decreased in the BPH group, whereas that of Mollicutes(P<0.05) and Prevotella(P<0.05)were significantly increased compared with the control group. Despite profound interindividual variability, the levels of several predominant genera were different. In addition, there were no statistically significant differences in several bacteria. BPH group vs. control group: Firmicutes(52.30% vs. 57.29%, P>0.05), Bacteroidetes(46.54% vs. 41.64%,P>0.05), Clostridia(50.89% vs. 54.66%, P>0.05), Ruminococcaceae(25.67% vs. 20.56%, P>0.05). LC–MS/MS of intestinal contents revealed that differential metabolites were mainly involved in cellular processes, environmental information processing, metabolism and organismal systems. The most important pathways were global and overview maps, lipid metabolism, amino acid metabolism, digestive system and endocrine system. Through enrichment analysis, we found that the differential metabolites were significantly enriched in metabolic pathways, steroid hormone biosynthesis,ovarian steroidogenesis, biosynthesis of unsaturated fatty acids and bile secretion. Pearson correlation analysis(R=0.94) showed that there was a strong correlation between Prevotellaceae, Corynebacteriaceae, Turicibacteraceae,Bifidobacteriaceae and differential metabolites.Conclusions: Our findings suggested an association between the gut microbiota and BPH, but the causal relationship between the two groups is unclear. Thus, further studies are warranted to elucidate the potential mechanisms and causal relationships between BPH and gut microbiota.
基金the National Science Foundation of China(41530967,41776173,41576129)the National Key Research and Development Program of China(2016YFC03007).
文摘The Southwest Indian Ridge,which is the slowest-spreading of the main ridges,separates the African and Antarctic plates.The slow expanding rate is associated with less density of hydrothermal vent fields,shorter longevity of hydrothermal activity,cold mantle temperatures and thick lithosphere.However,the microbial communities adapting to such specific characteristics of this area have remained largely unexplored.To study the microbial diversity at the Southwest Indian Ridge,we sampled three sediment cores in a newly found inactive vent field,the Tianzuo field,and used high-throughput sequencing of 16S rRNA genes to reveal the microbial composition.Microbial communities of three sampling sites were very similar at the surface,and underwent a gradient change along depth.Gammaproteobacteria,namely Alteromonadaceae,Nitrosococcus and the JTB255 marine benthic group,were the most dominant bacterial taxa.Marine Group I was the dominant archaeal taxon in our samples.In addition,microbial populations capable of ammonia oxidation,nitrite oxidation,sulfur oxidation and manganese oxidation were detected to be the main chemolithoautotrophs.The enrichment of sulfur-oxidizing and manganese-oxidizing bacteria was observed in deep layers.When compared with other vent fields along different ocean ridges,the Tianzuo field showed distinct composition in both archaeal and bacterial communities.These results provide the first view of microbial communities of the Tianzuo field at the Southwest Indian Ridge,and give a better understanding of metabolic potential possessed by the microbial populations.
基金supported by the National Natural Science Foundation of China(41471437)the National Key R&D Program of China(2016YFA0600801,2017YFC0504504)+1 种基金the West Light Foundation of the Chinese Academy of Science(XAB2016A04)the Key R&D Program of Ningxia Hui Autonomous Region,China(2022BBF02033)。
文摘Robinia pseudoacacia L.(RP)restoration has increased vegetation cover in semi-arid regions on the Loess Plateau of China,but ecological problems have also occurred due to RP restoration,such as reduced soil moisture.Further,it is still uncertain how microbial diversity,composition and assembly processes change with RP restoration in semi-arid regions.Therefore,amplicon sequencing of small subunit ribosomal ribonucleic acid(16S rRNA)and internal transcribed spacer(ITS)genes was performed to study soil bacterial and fungal diversity,composition and assembly processes at four study sites with different stand ages of RP plantations(Y10,RP plantation with stand ages less than 10 a;Y15,RP plantation with stand ages approximately 15 a;Y25,RP plantation with stand ages approximately 25 a;and Y40,RP plantation with stand ages approximately 40 a)along a 40-a chronosequence on the Loess Plateau.The diversity of soil bacteria and fungi increased significantly during the restoration period from 10 to 15 a(P<0.05).However,compared with Y15,bacterial diversity was lower at Y25 and Y40,and fungal diversity remained stable during the restoration period between 25 and 40 a.The relative abundances of Proteobacteria and Ascomycota increased during the restoration period from 10 to 15 a.Conversely,after 15 a of restoration,they both decreased,whereas the relative abundances of Actinomycetes,Acidobacteria and Basidiomycota gradually increased.The variations in soil bacterial communities were mainly related to changes in soil total nitrogen,nitrate nitrogen and moisture contents,while soil fungal communities were mainly shaped by soil organic carbon and nitrate nitrogen contents.Bacterial communities were structured by the heterogeneous selection and stochastic process,while fungal communities were structured primarily by the stochastic process.The RP restoration induced an increase in the relative importance of heterogeneous selection on bacterial communities.Overall,this study reveals the changes in microbial diversity,community composition and assembly processes with RP restoration on the Loess Plateau and provides a new perspective on the effects of vegetation restoration on soil microbial communities in semi-arid regions.
基金This study is supported by the National Basic Research Program(2002CB412307)the National High Technology Research and Development Program of China(Water Environment Program)(2002AA601011).
文摘In this study,PCR-denaturing gradient gel electrophoresis(DGGE)was applied to analyze the microbial communities in lake sediments from Lake Xuanwu,Lake Mochou in Nanjing and Lake Taihu in Wuxi.Sediment samples from seven locations in three lakes were collected and their genomic DNAs were extracted.The DNA yields of the sediments of Lake Xuanwu and Lake Mochou were high(10 mg/g),while that of sediments in Lake Taihu was relatively low.After DNA purification,the 16S rDNA genes(V3 to V5 region)were amplified and the amplified DNA fragments were separated by parallel DGGE.The DGGE profiles showed that there were five common bands in all the lake sediment samples indicating that there were similarities among the populations of microorganisms in all the lake sediments.The DGGE profiles of Lake Xuanwu and Lake Mochou were similar and about 20 types of micro-organisms were identified in the sediment samples of both lakes.These results suggest that the sediment samples of these two city lakes(Xuanwu,Mochou)have similar microbial communities.However,the DGGE profiles of sediment samples in Lake Taihu were significantly different from these two lakes.Furthermore,the DGGE profiles of sediment samples in different locations in Lake Taihu were also different,suggesting that the microbial communities in Lake Taihu are more diversified than those in Lake Xuanwu and Lake Mochou.The differences in microbial diversity may be caused by the different environmental conditions,such as redox potential,pH,and the concentrations of organic matters.Seven major bands of 16S rDNA genes fragments from the DGGE profiles of sediment samples were further reamplified and sequenced.The results of sequencing analysis indicate that five sequences shared 99%-100%homology with known sequences(Bacillus and Brevibacillus,uncultured bacteria),while the other two sequences shared 93%-96%homology with known sequences(Acinetobacter,and Bacillus).The study shows that the PCR-DGGE technique combined with sequence analysis is a feasible and efficient method for the determination of microbial communities in sediment samples.
基金study was funded by Major Special Science & Technology Project of Gansu Province (Grant No. Y839C01001).
文摘Timely removal of the flower is a key agricultural measure to ensure the concentrated supply of nutrients for the growth of underground bulbs and to increase the yield of lilies. Removing flowers and returning them to the field is one of the tradi‐tional ways of treatment, and field litter is formed at this time. Previous study showed that the decomposition of litter changes the soil properties. In order to study the effects of lily litter decomposition on soil physical and chemical proper‐ties and microbial structure, three treatments were set up in reference to the Decomposition Bag Method: control (CK), Lanzhou lily flower treatment (LZF), and Zhongbai No.1 flower treatment (ZBF). The effects of lily decomposition on soil physical and chemical properties and microbial community composition were studied in order to provide a scientific basis and theoretical guidance for the planting process of Lanzhou lily. The results show that the decomposition of lily flowers significantly increased the contents of soil organic matter, soil total nitrogen, soil total phosphorus and soil avail‐able potassium, and decreased soil pH. RDA shows that soil available nutrients and pH were the driving factors for the change of the soil microbial community. A short-term change of soil microenvironment caused by the decomposed lily flower is beneficial to growing the Lanzhou lily. However, under the correlation analysis of environmental factors, the long-term effects of returning the Lanzhou lily flower to the field, such as the trend of soil acidification, need to be further studied.
基金financially supported by the National Natural Science Foundation of China(Nos.32071561 and 31870431)the Science and Technology Innovation Program of Hunan Province(No.2021RC3104)+1 种基金the Research Foundation of the Education Bureau of Hunan Province(No.19B586)the Huitong Forest Ecological Station Funds provided by the State Forestry and Grass Administration of China(No.2021132078)。
文摘Tree species diversity is assumed to be an important component in managing forest ecosystems because of effects on multiple functions or ecosystem multifunctionality.However,the importance of tree diversity in determining multifunctionality in structurally complex subtropical forests relative to other regulators(e.g.,soil microbial diversity,stand structure,and environmental conditions)remains uncertain.In this study,effects of aboveground(species richness and functional and structural diversity)and belowground(bacterial and fungal diversity)biodiversity,functional composition(community-weighted means of species traits),stand structure(diameter at breast height and stand density),and soil factors(pH and bulk density)on multifunctionality(including biomass production,carbon stock,and nutrient cycling)were examined along a tree diversity gradient in subtropical forests.The community-weighted mean of tree maximum height was the best predictor of ecosystem multifunctionality.Functional diversity explained a higher proportion of the variation in multifunctionality than that of species richness and fungal diversity.Stand structure-played an important role in modulating the effects of tree diversity on multifunctionality.The work highlights that species composition and maximizing forest structural complexity are effective strategies to increase forest multifunctionality while also conserving biodiversity in the management of multifunctional forests under global environmental changes.
基金supported by grants from“Cataloguing,flora study and database establishment of mini-type fungi in Northeast Asia”from the Northeast Asia Biodiversity Research Center。
文摘Chinese peony(Paeonia lactiflora Pall.)is both medicinally and aesthetically beneficial.Powdery mildew is a common fungal disease that seriously jeopardizes the value of numerous species,including peonies as a crop.In order to provide a basis for the prevention and treatment of peony powdery mildew,we examined the microbial diversity,the malondialdehyde(MDA)concentrations and antioxidant enzyme activities of peony leaves infected with three levels of powdery mildew to determine any modifications to the leaf's antioxidant enzyme systems and microbial community structure following the onset of disease.The results show that the MDA content rose as the degree of infection became worse.Antioxidant enzyme activity rose and then declined.Following the initiation of powdery mildew,fungal community diversity decreased,whereas there was not any appreciable change in bacterial communities according to microbial diversity sequencing.The relative abundance of more than half of fungal species decreased,with the bacterial genera displaying both abundant and diminished communities with less pronounced alterations in their community structure after the disease spread.Significant different taxa that were critical to the organization of each microbiome were found.Correlation analysis showed that the relative abundance of powdery mildew pathogenic fungal genus Erysiphe was correlated with those of 11 fungal genera and one bacterial genus.Among them,Aureobasidium,Neosetophoma and Sclerostagonospora showed significant positive correlations with Erysiphe and MDA.
基金supported by Major Science and Technology Projects of Yunnan Science and Technology Plan(2019ZG003)Yunnan Young and Middle-aged Academic and Technical Leader Reserve Talent Project(202105AC160068)。
文摘The internal microbial diversity and small molecular metabolites of Nuodeng ham in different processing years(the first,second and third year sample)were analyzed by high-throughput sequencing technology and gas chromatography-time of flight mass spectrography(GC-TOF-MS)to study the effects of microorganisms and small molecular metabolites on the quality of ham in different processing years.The results showed that the dominant bacteria phyla of Nuodeng ham in different processing years were Proteobacteria and Firmicutes,the dominant fungi phyla were Ascomycota and Basidiomycota,while Staphylococcus and Aspergillus were the dominant bacteria and fungi of Nuodeng ham,respectively.Totally,252 kinds of small molecular metabolites were identified from Nuodeng ham in different processing years,and 12 different metabolites were screened through multivariate statistical analysis.Further metabolic pathway analysis showed that 23 metabolic pathways were related to ham fermentation,of which 8 metabolic pathways had significant effects on ham fermentation(Impact>0.01,P<0.05).The content of L-proline,phenyllactic acid,L-lysine,carnosine,taurine,D-proline,betaine and creatine were significantly positively correlated with the relative abundance of Staphylococcus and Serratia,but negatively correlated with the relative abundance of Halomonas,Aspergillus and Yamadazyma.