With the development of transgenic crops, there is an increasing concern about the possible adverse effects of their vegetation and residues on soil environmental quality. This study was carried out to evaluate the po...With the development of transgenic crops, there is an increasing concern about the possible adverse effects of their vegetation and residues on soil environmental quality. This study was carried out to evaluate the possible effects of the vegetation of transgenic Bt rice lines Huachi B6 （HC） and TT51 （TT） followed by the return of their straw to the soil on soil enzymes （catalase, urease, neutral phosphatase and invertase）, anaerobic respiration activity, microbial utilization of carbon substrates and community structure, under field conditions. The results indicated that the vegetation of the two transgenic rice lines （HC and TT） and return of their straw had few adverse effects on soil enzymes and anaerobic respiration activity compared to their parent and distant parent, although some transient differences were observed. The vegetation and subsequent straw amendment of Bt rice HC and TT did not appear to have a harmful effect on the richness, evenness and community structure of soil microorganisms. No different pattern of impact due to plant species was found between HC and TT. It could be concluded that the vegetation of transgenic Bt rice lines and the return of their straw as organic fertilizer may not alter soil microbe-mediated functions.展开更多
The aim of this work was to assess the effect of applying three different doses of fluxapyroxad on microbial activity, community structure and functional diversity as measured by respiration, microbial biomass C, phos...The aim of this work was to assess the effect of applying three different doses of fluxapyroxad on microbial activity, community structure and functional diversity as measured by respiration, microbial biomass C, phospholipid fatty acid （PLFA） and community-level physiological profiles （CLPPs）. Our results demonstrated that substrate-induced respiration （on day 15） and microbial biomass C （on days 7 and 15） were inhibited by fiuxapyroxad, but stimulation was observed thereafter. In contrast, fluxapyroxad addition increased the basal respiration and metabolic quotients （qCO2） and respiratory quotients （QR）. Analysis of the PLFA profiles revealed that the total and bacterial biomass （both Gram-positive bacteria （GP） and Gram-negative bacteria （GN）） were decreased within the initial 15 days, whereas those as well as the GN/GP ratio were increased at days 30 and 60. Fluxapyroxad input decreased the fungi biomass but increased the bacteria/fungi ratio at all incubation time. Moreover, high fluxapyroxad input （75 mg fluxapyroxad kg-1 soil dry weight） increased the microbial stress level. A principal component analysis （PCA） of the PLFAs revealed that fluxapyroxad treatment significantly shifted the microbial community structure, but all of the observed effects were transient. Biolog results showed that average well color development （AWCD） and functional diversity index （H′） were increased only on day 60. In addition, the dissipation of fluxa- pyroxad was slow in soil, and the degradation half-lives varied from 158 to 385 days depending on the concentration tested.展开更多
Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental ...Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental characteristics especially organic carbon availability after 15-yr different organic and inorganic fertilizer inputs on soil bacterial community structure and functional metabolic diversity of soil microbial communities were evaluated in a 15-yr fertilizer experiment in Changping County, Beijing, China. The experiment was a wheat-maize rotation system which was established in 1991 including four different fertilizer treatments. These treatments included： a non-amended control（CK）, a commonly used application rate of inorganic fertilizer treatment（NPK）; a commonly used application rate of inorganic fertilizer with swine manure incorporated treatment（NPKM）, and a commonly used application rate of inorganic fertilizer with maize straw incorporated treatment（NPKS）. Denaturing gradient gel electrophoresis（DGGE） of the 16 S r RNA gene was used to determine the bacterial community structure and single carbon source utilization profiles were determined to characterize the microbial community functional metabolic diversity of different fertilizer treatments using Biolog Eco plates. The results indicated that long-term fertilized treatments significantly increased soil bacterial community structure compared to CK. The use of inorganic fertilizer with organic amendments incorporated for long term（NPKM, NPKS） significantly promoted soil bacterial structure than the application of inorganic fertilizer only（NPK）, and NPKM treatment was the most important driver for increases in the soil microbial community richness（S） and structural diversity（H）. Overall utilization of carbon sources by soil microbial communities（average well color development, AWCD） and microbial substrate utilization diversity and evenness indices（H＇ and E） indicated that long-term inorganic fertilizer with organic amendments incorporated（NPKM, NPKS） could significantly stimulate soil microbial metabolic activity and functional diversity relative to CK, while no differences of them were found between NPKS and NPK treatments. Principal component analysis（PCA） based on carbon source utilization profiles also showed significant separation of soil microbial community under long-term fertilization regimes and NPKM treatment was significantly separated from the other three treatments primarily according to the higher microbial utilization of carbohydrates, carboxylic acids, polymers, phenolic compounds, and amino acid, while higher utilization of amines/amides differed soil microbial community in NPKS treatment from those in the other three treatments. Redundancy analysis（RDA） indicated that soil organic carbon（SOC） availability, especially soil microbial biomass carbon（Cmic） and Cmic/SOC ratio are the key factors of soil environmental characteristics contributing to the increase of both soil microbial community structure and functional metabolic diversity in the long-term fertilization trial. Our results showed that long-term inorganic fertilizer and swine manure application could significantly improve soil bacterial community structure and soil microbial metabolic activity through the increases in SOC availability, which could provide insights into the sustainable management of China＇s soil resource.展开更多
Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated...Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated under variable nutrient levels is lacking.Here,biofilm colonization patterns and community structures responding to variable levels of ammonia and sulfate were explored.From field sampling,NH_(4)^(+)-N was proven key factor governing community structure in attached biofilms,verifying the reliability of selecting target nutrient species in batch experiments.Biofilms exhibited significant compositional differences in field sampling and incubation experiments.As the nutrient increased in batch experiments,the growth of biofilms gradually slowed down and uneven distribution was detected.The proportions of proteins and β-d-glucose polysaccharides in biofilms experienced a decrease in response to elevated levels of nutrients.With the increased of nutrients,themass losses of concretes exhibited an increase,reaching a highest value of 2.37%in the presence of 20 mg/L of ammonia.Microbial communities underwent a significant transition in structure and metabolic functions to ammonia gradient.The highest activity of nitrification was observed in biofilms colonized in the presence of 20 mg/L of ammonia.While the communities and their functions remained relativelymore stable responding to sulfate gradient.Our research provides novel insights into the structures of biofilms attached on HCSs and the metabolic functions in the presence of high level of nutrients,which is of significance for the operation and maintenance of hydraulic engineering structures.展开更多
Mountain systems harbor an evolutionarily unique and exceptionally rich biodiversity,especially for amphibians.However,the associated elevational gradients and underlying mechanisms of amphibian diversity in most moun...Mountain systems harbor an evolutionarily unique and exceptionally rich biodiversity,especially for amphibians.However,the associated elevational gradients and underlying mechanisms of amphibian diversity in most mountain systems remain poorly understood.Here,we explored amphibian phylogenetic and functional diversity along a 2600 m elevational gradient on Mount Emei on the eastern margin of the Qinghai-Tibetan Plateau in southwestern China.We also assessed the relative importance of spatial(area)and environmental factors(temperature,precipitation,solar radiation,normalized difference vegetation index,and potential evapotranspiration)in shaping amphibian distribution and community structure.Results showed that the phylogenetic and functional diversities were unimodal with elevation,while the standardized effect size of phylogenetic and functional diversity increased linearly with elevation.Phylogenetic net relatedness,nearest taxon index,and functional net relatedness index all showed a positive to negative trend with elevation,indicating a shift from clustering to overdispersion and suggesting a potential change in key processes from environmental filtering to competitive exclusion.Overall,our results illustrate the importance of deterministic processes in structuring amphibian communities in subtropical mountains,with the dominant role potentially switching with elevation.This study provides insights into the underlying assembly mechanisms of mountain amphibians,integrating multidimensional diversity.展开更多
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore...In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques： such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals.展开更多
Multi-generational planting of Eucalyptus species degrades soil quality but the introduction of legumes can improve soil fertility and microbial diversity.However,the effects of introducing non-legume native tree spec...Multi-generational planting of Eucalyptus species degrades soil quality but the introduction of legumes can improve soil fertility and microbial diversity.However,the effects of introducing non-legume native tree species on soil nutrients and bacterial community structure remain poorly understood.This study investigated the impacts of the conversion of third generation monoculture Eucalyptus plantations to mixed systems including Eucalyptus urograndis with Cinnamomum camphora(EC)and E.urograndis with Castanopsis hystrix(EH),on soil chemical and biochemical properties and bacterial community structure,diversity and functions.First generation E.urophylla plantations were the control.Results show that planting the third generation Eucalyptus led to a significant decrease in p H,organic matter,nutrient content,enzyme activities(invertin,acid phosphataes,and urease),and bacterialα-diversity compare to the controls.However,the mixed planting showed significant improvement in soil chemical and biochemical attributes and bacterialα-diversity,although the E.urograndis and C.hystrix planting had no improvement.Chloroflexi(oligotrophic bacteria)were significantly enriched in third generation Eucalyptus and Eucalyptus+C.hystrix,while proteobacteria increased significantly in the E.urograndis with C.camphora plantings.The relative abundance of multiple metabolic pathways increased significantly in the third generation Eucalyptus plantations whereas membrane transportrelated genes were enriched in soils of the mixed systems.The changes in bacterial community structures in the two mixed systems were driven by diversity,organic matter and acid phosphatase,while bacterial functions were affected by invertase,NO_(3)^(-)-N,diversity and urease.These results suggest that the transformation of successive monoculture Eucalyptus plantations into mixed plantations reduces the depletion of soil nutrients and enhances the ecological function of soil microorganisms.展开更多
Wettability affects the immiscible flow process of the gas-water phases in coalbed methane reservoirs,which has an important effect on coalbed methane production.The sessile drop method,infrared spectroscopy and atomi...Wettability affects the immiscible flow process of the gas-water phases in coalbed methane reservoirs,which has an important effect on coalbed methane production.The sessile drop method,infrared spectroscopy and atomic force microscopy(AFM)were used to study the wettability,functional groups and pore structure of 8 coal rocks with middle ranks from the Qinshui Basin,North China,and the Junggar Basin,Northwest China.The pore structure of the coal sample,including the porosity,number of pores,pore area,pore diameter,percentage of different types of pores and roughness under the scale of 50 mm,was determined using the Nanoscope and Gwyddion analysis methods.The relationships between the pore structure,functional groups,coal surface roughness and wettability were studied.The results show that the larger the proportion of macropores on the coal surface is,the stronger the hydrophilicity of coal.The more oxygen-containing functional groups there are,the better the wettability of coal and rock.The contact angle has a sinusoidal relationship with the roughness due to the change in the adsorption point.For coal with very low or very high roughness,the contact angle is negatively correlated with the roughness,while for coal with low to average roughness,the contact angle is significantly positively correlated with the roughness.This work provides new insights into the interactions between water molecules and the coal pore surface.展开更多
Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed （Phragmites communis） colonizatio...Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed （Phragmites communis） colonization. The structures of bacterial communities were investigated using culture-independent 16S rRNA gene sequencing method. The bacterial diversity in the bare mine tailing was lower than that of the vegetated mine tailing. The former was dominated by sulfur metabolizing bacteria, whereas the latter was by nitrogen fixing bacteria. The bare mine tailing was acidic （pH = 3.78）, whereas the vegetated mine tailing was near neutral （pH ： 7.28）. The contents of organic matter, total nitrogen, and ammonium acetate-extractable potassium in vegetated mine tailings were significantly higher than those in the bare mine railings （P 〈 0.01）, whereas available phosphorus and electrical conductivity were significantly lower than those in the bare mine tailings （P 〈 0.01）. The results demonstrated that 16S rRNA gene sequencing could be successfully used to study the bacterial diversity in mine tailings. The colonization of the mine tailings by reed significantly changed the bacterial community and the chemical properties of tailings. The complex interactions between bacteria and plants deserve further investigation.展开更多
It has been well documented that organic amendment affects soil nematode community structure.However,little is known about the effect of organic amendment amount on soil nematodes.To assess the effect of the amount of...It has been well documented that organic amendment affects soil nematode community structure.However,little is known about the effect of organic amendment amount on soil nematodes.To assess the effect of the amount of organic amendments on soil nematode community structure and metabolic activity,the community composition,abundance,and metabolic footprints of soil nematodes were determined in a long-term field experiment with various amounts of organic amendment in Northeast China.Fertilization treatments included an unfertilized control(CK),chemical fertilizer without manure amendment(OM0),manure applied at 7.5 Mg ha^-1 plus chemical fertilizer(OM1),and manure applied at 22.5 Mg ha^-1 plus chemical fertilizer(OM2).A total of 46 nematode genera were found.Treatments with the largest amount of organic amendment had the smallest number of plant parasite genera(5),but a largest number of dominant genera(7).Soil nematodes,bacterivores,and fungivores were the most abundant in OM2,followed by OM1,and the lowest in OM0 and CK.Organic amendment increased the enrichment index(EI),and the large amount of organic amendment increased the metabolic footprints of bacterivore(Baf)and fungivore(Fuf)and enrichment footprint(Ef).The relationships between Baf(or Fuf)and the increases in soil organic carbon(?SOC)and total nitrogen(?TN)were stronger than those of bacterivore(or fungivore)abundance with?SOC and?TN,except for the relationship between bacterivore abundance and ?SOC.The EI and Ef were positively correlated with ?SOC and ?TN.These findings suggest that the amount of organic amendment affects soil nematode activity and function at entry levels in soil food web,and that metabolic footprints of soil nematodes may be better indicators than their abundances in assessing their relationships with soil nutrients.展开更多
Aims Functional group composition of a plant community is mainly driven by environmental factors and is one of the main determinants of grassland biodiversity and productivity.Therefore,it is important to understand t...Aims Functional group composition of a plant community is mainly driven by environmental factors and is one of the main determinants of grassland biodiversity and productivity.Therefore,it is important to understand the role of plant functional groups(PFGs)in mediating the impact of environmental conditions on ecosystem functions and biodiversity.Methods We measured plant biomass and species richness(SR)of grasslands in 65 sites on the Mongolian Plateau and classified 157 perennial herbaceous plants into two main PFGs(namely grasses and forbs).Using the random forest model and ordinary least squares regression,we identified that environmental factors(i.e.aridity index,soil total nitrogen[STN]and pH)were significantly related to the SR and aboveground biomass(AGB)of PFGs.We then used structural equation modeling to explore the relationship between the identified environmental factors and community SR and biomass,and the role of PFGs in driving this relationship.Important Findings We found that aridity index had unimodal relationships with both AGB and SR of the PFGs and the whole community.All SR and biomass metrics were significantly related to STN and pH.The relationship between aridity index and community biomass was mediated by an increase in the AGB of grasses.The influence of STN and pH on community SR was mainly due to their regulation in the SR of forbs.Our results indicate that community composition and the identity of the PFGs play a key role in linking environmental factors to ecosystem functioning.展开更多
The incredibly complex soil microbial communities at small scales make their analysis and identification of reasons for the observed structures challenging.Microbial community structure is mainly a result of the inocu...The incredibly complex soil microbial communities at small scales make their analysis and identification of reasons for the observed structures challenging.Microbial community structure is mainly a result of the inoculum(dispersal),the selective advantages of those organisms under the habitat-based environmental attributes,and the ability of those colonizers to sustain themselves over time.Since soil is protective,and its microbial inhabitants have long adapted to varied soil conditions,significant portions of the soil microbial community structure are likely stable.Hence,a substantial portion of the community will not correlate to often measured soil attributes.We suggest that the drivers be ranked on the basis of their importance to the fundamental needs of the microbes:(i)those that supply energy,i.e.,organic carbon and electron acceptors;(i)environmental effectors or stressors,i.e.,pH,salt,drought,and toxic chemicals;(ii)macro-organism associations,i.e.,plants and their seasonality,animals and their fecal matter,and soil fauna;and(iv)nutrients,in order,N,P,and probably of lesser importance,other micronutrients,and metals.The relevance of drivers also varies with spatial and time scales,for example,aggregate to field to regional,and persistent to dynamic populations to transcripts,and with the extent of phylogenetic difference,hence phenotypic differences in organismal groups.We present a summary matrix to provide guidance on which drivers are important for particular studies,with special emphasis on a wide range of spatial and temporal scales,and illustrate this with genomic and population(rRNA gene)data from selected studies.展开更多
The potential ecotoxicologial risks of methamidophos,copper,and their combinations on microbial community of black soil ecosystem in the Northeast China were assessed in species richness and structures by using 16S rD...The potential ecotoxicologial risks of methamidophos,copper,and their combinations on microbial community of black soil ecosystem in the Northeast China were assessed in species richness and structures by using 16S rDNA-PCR-DGGE analysis approach,and functional characteristics at community levels by using BIOLOG^(GN) system analysis method as well as two conventional methods(DHA and SIR).All results of DGGE banding fingerprint patterns(amplified by bacterial specific 16S rDNA V_(3) high variable region universal primer)indicated that the species richness of bacterial community in tested soil was significantly decreased to different extents by using different concentrations of single methamidophos,copper,especially some of their combinations had worse effects than their corresponding single factors.In addition,the structures of soil bacterial community had been disturbed under all stresses applied in this study because of the enrichment of some species and the disappearance of other species from the bacterial community.The effects of the single factors with lower concentrations on the communiy structure were weaker than those with higher concentrations.Moreover,the bacterial community structures under the combined stresses of methamidophos and copper were significantly different from those of control and their corresponding single factors.The change of DHA and carbon source substrate utilizing fingerprint patterns based on BIOLOG^(GN)system were two relatively sensitive directors corresponding to the stress presented in this study.Between methamodophos and copper,there happened the significant joint-toxic actions when they were used in combination on DHA and carbon source substrate utilizing fingerprint patterns of soil bacterial communities.The DHA of soil under the combined stresses was lower than that of the control and that under the single factors,and the BIOLOG^(GN) substrate utilizing patterns of soil treated by combinations were distinctively differentiated from the control and their corresponding single factors.From all of above,the methamidophos,copper,especially their combinations had the clearly potential ecotoxicological risks to influence the natural soil microbial ecological system by changing the structure,richness,and the functional characteristics of microbial community.展开更多
Anaerobic digestion(AD),as an eco-friendly biological process,shows potential for the decomposition of leachate produced by waste incineration power plants.In this study,the effects of Fe oxides nano-modified pumice(F...Anaerobic digestion(AD),as an eco-friendly biological process,shows potential for the decomposition of leachate produced by waste incineration power plants.In this study,the effects of Fe oxides nano-modified pumice(FNP)were investigated on the fresh leachate AD process.Firstly,a simple hydrothermal method was used to prepare FNP,then introduced into the UASB reactor to evaluate its AD efficiency.Results showed that the inclusion of FNP could shorten the lag phase by 10 days compared to the control group.Furthermore,cumulative methane production in the FNP group was enhanced by 20.11%.Mechanistic studies suggested that hydrogenotrophic methanogenesis in the FNP group was more pronounced due to the influence of key enzymes(i.e.,dehydrogenase and coenzyme F420).Microbial community analysis demonstrated that FNP could enhance the abundance of Methanosarcina,Proteobacteria,Sytrophomonas,and Limnobacter,which might elevate enzyme activity involved in methane production.These findings suggest that FNP might mediate interspecies electron transfer among these microorganisms,which is essential for efficient leachate treatment.展开更多
Few studies have examined the succession of plant communities in the alpine zone.Studying the succession of plant communities is helpful to understand how species diversity is formed and maintained.In this study,we us...Few studies have examined the succession of plant communities in the alpine zone.Studying the succession of plant communities is helpful to understand how species diversity is formed and maintained.In this study,we used species inventories,a molecular phylogeny,and trait data to detect patterns of phylogenetic and functional community structure in successional plant communities growing on the mounds of Himalayan marmots(Marmota himalayana)on the southeast edge of the Qinghai-Tibet Plateau.We found that phylogenetic and functional diversities of plant communities on marmot mounds tended to cluster during the early to medium stages of succession,then trended toward overdispersion from medium to late stages.Alpine species in early and late stages of succession were phylogenetically and functionally overdispersed,suggesting that such communities were assembled mainly through species interactions,especially competition.At the medium and late stages of succession,alpine communities growing on marmot mounds were phylogenetically and functionally clustered,implying that the communities were primarily structured by environmental filtering.During the medium and late stages of succession the phylogenetic and functional structures of plant communities on marmot mounds differed significantly from those on neighboring sites.Our results indicate that environmental filtering and species interactions can change plant community composition at different successional stages.Assembly of plant communities on marmot mounds was promoted by a combination of traits that may provide advantages for survival and adaptation during periods of environmental change.展开更多
The presence of oxygen functional groups is detrimental to the capacitive performance of porous carbon electrode in organic electrolyte. In this regards, hydrogen thermal reduction has been demonstrated effective appr...The presence of oxygen functional groups is detrimental to the capacitive performance of porous carbon electrode in organic electrolyte. In this regards, hydrogen thermal reduction has been demonstrated effective approach in removing the unstable surface oxygen while maintaining the high porosity of carbon matrix. However, the exact evolution mechanism of various oxygen species during this process, as well as the correlation with electrochemical properties, is still under development. Herein, biomass-based porous carbon is adopted as the model material to trace its structure evolution of oxygen removal under hydrogen thermal reduction process with the temperature range of 400–800 °C. The optimum microstructure with low oxygen content of 0.90% and proper pore size distribution was achieved at 700°C. XPS, TPRMS and Boehm titration results indicate that the oxygen elimination undergoes three distinctive stages(intermolecular dehydration, hydrogenation and decomposition reactions). The optimum microstructure with low oxygen content of 0.90% and proper pore size distribution was achieved at 700 °C. Benefiting from the stable electrochemical interface and the optimized porous structure, the as-obtained HAC-700 exhibit significantly suppressed self-discharge and leak current, with improved cycling stability, which is attributable to the stabilization of electrochemical interface between carbon surface and electrolyte. The result provides insights for rational design of surface chemistry for high-performance carbon electrode towards advanced energy storage.展开更多
Improving soil quality while achieving higher productivity is the major challenge in the agricultural industry. Wheat(Triticum aestivum L.)–maize(Zea mays L.)(W–M) rotation is the dominant planting pattern in the Hu...Improving soil quality while achieving higher productivity is the major challenge in the agricultural industry. Wheat(Triticum aestivum L.)–maize(Zea mays L.)(W–M) rotation is the dominant planting pattern in the Huang-HuaiHai Plain and is important for food security in China. However, the soil quality is deteriorating due to the W–M rotation’s long-term, intensive, and continuous cultivation. Introducing legumes into the W–M rotation system may be an effective way to improve soil quality. In this study, we aimed to verify this hypothesis by exploring efficient planting systems(wheat–peanut(Arachis hypogaea L.)(W–P) rotation and wheat rotated with maize and peanut intercropping(W–M/P)) to achieve higher agricultural production in the Huang-Huai-Hai Plain. Using traditional W–M rotation as the control, we evaluated crop productivity, net returns, soil microorganisms(SMs), and soil organic carbon(SOC) fractions for three consecutive years. The results indicated that wheat yields were significantly increased under W–P and W–M/P(382.5–579.0 and 179.8–513.1 kg ha-1, respectively) compared with W–M. W–P and W–M/P provided significantly higher net returns(58.2 and 70.4%, respectively) than W–M. W–M/P and W–M retained the SOC stock more efficiently than W–P, increasing by 25.46–31.03 and 14.47–27.64%, respectively, in the 0–20 cm soil layer. Compared with W–M, W–M/P improved labile carbon fractions;the sensitivity index of potentially mineralizable carbon, microbial biomass carbon(MBC), and dissolved organic carbon was 31.5, 96.5–157.2, and 17.8% in 20–40, 10–40, and 10–20 cm soil layers, respectively. The bacterial community composition and bacteria function were altered as per the soil depth and planting pattern. W–M/P and W–M exhibited similar bacterial community composition and function in 0–20 and 20–40 cm soil layers. Compared with W–P, a higher abundance of functional genes, namely, contains mobile elements and stress-tolerant, and a lower abundance of genes, namely,potentially pathogenic, were observed in the 10–20 cm soil layer of W–M and the 0–20 cm soil layer of W–M/P. SOC and MBC were the main factors affecting soil bacterial communities, positively correlated with Sphingomonadales and Gemmatimonadales and negatively correlated with Blastocatellales. Organic input was the main factor affecting SOC and SMs, which exhibited feedback effects on crop productivity. In summary, W–M/P improved productivity, net returns, and SOC pool compared with traditional W–M rotation systems, and it is recommended that plant–soil–microbial interactions be considered while designing high-yield cropping systems.展开更多
为了系统探讨煤自燃倾向性的影响因素,基于逐步回归分析方法,提出以煤样的工业分析参数、孔隙结构参数、官能团含量和燃烧活化能为自变量,燃点温度为因变量预测煤自燃模型,揭示煤自燃特性与微观结构间的关联。结果表明:6个煤样的孔隙分...为了系统探讨煤自燃倾向性的影响因素,基于逐步回归分析方法,提出以煤样的工业分析参数、孔隙结构参数、官能团含量和燃烧活化能为自变量,燃点温度为因变量预测煤自燃模型,揭示煤自燃特性与微观结构间的关联。结果表明:6个煤样的孔隙分形维数平均值为2.770,孔隙结构较为复杂,煤氧反应时可以提供更多的吸附位点;XL3的燃点温度最低为486℃,燃烧活化能也最低,为82.01 k J/mol;燃点温度y=381.152-1.494S_(BET)+21.550I_(C-O),R^(2)=0.998,表明了BET比表面积和C—O峰强度可以解释燃点温度99.8%变化的原因,且C—O峰强度对燃点温度的影响更为显著。研究结果揭示了煤体孔隙比表面积与含氧官能团是控制自燃倾向性的核心因素,为煤自燃风险评估提供了理论依据。展开更多
[Objectives]This study was conducted to analyze species composition, community appearance, plant life-type spectrum, flora distribution, plant community structure and plant diversity indexes of Mingyue Park in Jingzho...[Objectives]This study was conducted to analyze species composition, community appearance, plant life-type spectrum, flora distribution, plant community structure and plant diversity indexes of Mingyue Park in Jingzhou City, as well as the ecological functions of plants in cooling, humidification, shading, and noise reduction. [Methods] A quadart method was used to investigate plant communitues of Mingyue Park in Jingzhou City. [Results] There were 141 species in the park, including 44 tree speceies, 35 shrub speceies, and 62 herb speceies. The arber-shrub-grass structure was the dominant plant community structure. The Simpson index(D), Shannon-Wiener index(H) and Pielou index(J) of the herb layer were higher than those of the tree layer and the shrub layer, and the shrub layer was the lowest. The results of ecological function research showed that the plant communities had a significant shading effect and a certain ability to reduce noise. The comprehensive conclusion showed that the ecological function indexes of the arbor-shrub-grass structure in Mingyue Park were significantly higher than those of the arbor-shrub structure and the single-tree structure. In order to improve the ecological benefits of plant communities in Mingyue Park, the plant diversity can be increased in the later construction to enrich community structures. [Conclusions] This study evaluated the ecological benefits of plant communities in Mingyue Park, and provides a scientific basis for the plant configuration of parks in Jingzhou and other regions.展开更多
基金supported by the Genetically Modified Organisms Breeding Major Projects (No. 2009ZX08011-014B, 2009ZX08011-008B)the Major State Basic Research Development Programme of China (No.2009CB119006)the National Natural Science Foundation of China (No. 20877068, 30771254)
文摘With the development of transgenic crops, there is an increasing concern about the possible adverse effects of their vegetation and residues on soil environmental quality. This study was carried out to evaluate the possible effects of the vegetation of transgenic Bt rice lines Huachi B6 （HC） and TT51 （TT） followed by the return of their straw to the soil on soil enzymes （catalase, urease, neutral phosphatase and invertase）, anaerobic respiration activity, microbial utilization of carbon substrates and community structure, under field conditions. The results indicated that the vegetation of the two transgenic rice lines （HC and TT） and return of their straw had few adverse effects on soil enzymes and anaerobic respiration activity compared to their parent and distant parent, although some transient differences were observed. The vegetation and subsequent straw amendment of Bt rice HC and TT did not appear to have a harmful effect on the richness, evenness and community structure of soil microorganisms. No different pattern of impact due to plant species was found between HC and TT. It could be concluded that the vegetation of transgenic Bt rice lines and the return of their straw as organic fertilizer may not alter soil microbe-mediated functions.
基金supported by the National Natural Science Foundation of China (31171879 and 31000863)the Special Fund for Agro-Scientific Research in the Public Interest, China (201203098)
文摘The aim of this work was to assess the effect of applying three different doses of fluxapyroxad on microbial activity, community structure and functional diversity as measured by respiration, microbial biomass C, phospholipid fatty acid （PLFA） and community-level physiological profiles （CLPPs）. Our results demonstrated that substrate-induced respiration （on day 15） and microbial biomass C （on days 7 and 15） were inhibited by fiuxapyroxad, but stimulation was observed thereafter. In contrast, fluxapyroxad addition increased the basal respiration and metabolic quotients （qCO2） and respiratory quotients （QR）. Analysis of the PLFA profiles revealed that the total and bacterial biomass （both Gram-positive bacteria （GP） and Gram-negative bacteria （GN）） were decreased within the initial 15 days, whereas those as well as the GN/GP ratio were increased at days 30 and 60. Fluxapyroxad input decreased the fungi biomass but increased the bacteria/fungi ratio at all incubation time. Moreover, high fluxapyroxad input （75 mg fluxapyroxad kg-1 soil dry weight） increased the microbial stress level. A principal component analysis （PCA） of the PLFAs revealed that fluxapyroxad treatment significantly shifted the microbial community structure, but all of the observed effects were transient. Biolog results showed that average well color development （AWCD） and functional diversity index （H′） were increased only on day 60. In addition, the dissipation of fluxa- pyroxad was slow in soil, and the degradation half-lives varied from 158 to 385 days depending on the concentration tested.
基金funded by the National Natural Science Foundation of China(NSFC31301843)the National Nonprofit Institute Research Grant of Chinese Academy of Agricultural Sciences(IARRP-202-5)
文摘Exploration of soil environmental characteristics governing soil microbial community structure and activity may improve our understanding of biogeochemical processes and soil quality. The impact of soil environmental characteristics especially organic carbon availability after 15-yr different organic and inorganic fertilizer inputs on soil bacterial community structure and functional metabolic diversity of soil microbial communities were evaluated in a 15-yr fertilizer experiment in Changping County, Beijing, China. The experiment was a wheat-maize rotation system which was established in 1991 including four different fertilizer treatments. These treatments included： a non-amended control（CK）, a commonly used application rate of inorganic fertilizer treatment（NPK）; a commonly used application rate of inorganic fertilizer with swine manure incorporated treatment（NPKM）, and a commonly used application rate of inorganic fertilizer with maize straw incorporated treatment（NPKS）. Denaturing gradient gel electrophoresis（DGGE） of the 16 S r RNA gene was used to determine the bacterial community structure and single carbon source utilization profiles were determined to characterize the microbial community functional metabolic diversity of different fertilizer treatments using Biolog Eco plates. The results indicated that long-term fertilized treatments significantly increased soil bacterial community structure compared to CK. The use of inorganic fertilizer with organic amendments incorporated for long term（NPKM, NPKS） significantly promoted soil bacterial structure than the application of inorganic fertilizer only（NPK）, and NPKM treatment was the most important driver for increases in the soil microbial community richness（S） and structural diversity（H）. Overall utilization of carbon sources by soil microbial communities（average well color development, AWCD） and microbial substrate utilization diversity and evenness indices（H＇ and E） indicated that long-term inorganic fertilizer with organic amendments incorporated（NPKM, NPKS） could significantly stimulate soil microbial metabolic activity and functional diversity relative to CK, while no differences of them were found between NPKS and NPK treatments. Principal component analysis（PCA） based on carbon source utilization profiles also showed significant separation of soil microbial community under long-term fertilization regimes and NPKM treatment was significantly separated from the other three treatments primarily according to the higher microbial utilization of carbohydrates, carboxylic acids, polymers, phenolic compounds, and amino acid, while higher utilization of amines/amides differed soil microbial community in NPKS treatment from those in the other three treatments. Redundancy analysis（RDA） indicated that soil organic carbon（SOC） availability, especially soil microbial biomass carbon（Cmic） and Cmic/SOC ratio are the key factors of soil environmental characteristics contributing to the increase of both soil microbial community structure and functional metabolic diversity in the long-term fertilization trial. Our results showed that long-term inorganic fertilizer and swine manure application could significantly improve soil bacterial community structure and soil microbial metabolic activity through the increases in SOC availability, which could provide insights into the sustainable management of China＇s soil resource.
基金supported by the National Key Research and Development Project of China(No.2021YFB2600200)the National Natural Science Foundation of China(Nos.52470185 and 52170159)the Open Research Fund of National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,the Fund of National Key Laboratory of Water Disaster Prevention and Key Research and Development Program of Jiangsu Province(No.BE2022601).
文摘Microbial corrosion of hydraulic concrete structures(HCSs)has received increasing research concerns.However,knowledge on the morphology of attached biofilms,as well as the community structures and functions cultivated under variable nutrient levels is lacking.Here,biofilm colonization patterns and community structures responding to variable levels of ammonia and sulfate were explored.From field sampling,NH_(4)^(+)-N was proven key factor governing community structure in attached biofilms,verifying the reliability of selecting target nutrient species in batch experiments.Biofilms exhibited significant compositional differences in field sampling and incubation experiments.As the nutrient increased in batch experiments,the growth of biofilms gradually slowed down and uneven distribution was detected.The proportions of proteins and β-d-glucose polysaccharides in biofilms experienced a decrease in response to elevated levels of nutrients.With the increased of nutrients,themass losses of concretes exhibited an increase,reaching a highest value of 2.37%in the presence of 20 mg/L of ammonia.Microbial communities underwent a significant transition in structure and metabolic functions to ammonia gradient.The highest activity of nitrification was observed in biofilms colonized in the presence of 20 mg/L of ammonia.While the communities and their functions remained relativelymore stable responding to sulfate gradient.Our research provides novel insights into the structures of biofilms attached on HCSs and the metabolic functions in the presence of high level of nutrients,which is of significance for the operation and maintenance of hydraulic engineering structures.
基金supported by the National Natural Science Foundation of China(31770568,32071544)Natural Science Foundation of Shanghai(20ZR1418100)“Light of West China”Program of the Chinese Academy of Sciences。
文摘Mountain systems harbor an evolutionarily unique and exceptionally rich biodiversity,especially for amphibians.However,the associated elevational gradients and underlying mechanisms of amphibian diversity in most mountain systems remain poorly understood.Here,we explored amphibian phylogenetic and functional diversity along a 2600 m elevational gradient on Mount Emei on the eastern margin of the Qinghai-Tibetan Plateau in southwestern China.We also assessed the relative importance of spatial(area)and environmental factors(temperature,precipitation,solar radiation,normalized difference vegetation index,and potential evapotranspiration)in shaping amphibian distribution and community structure.Results showed that the phylogenetic and functional diversities were unimodal with elevation,while the standardized effect size of phylogenetic and functional diversity increased linearly with elevation.Phylogenetic net relatedness,nearest taxon index,and functional net relatedness index all showed a positive to negative trend with elevation,indicating a shift from clustering to overdispersion and suggesting a potential change in key processes from environmental filtering to competitive exclusion.Overall,our results illustrate the importance of deterministic processes in structuring amphibian communities in subtropical mountains,with the dominant role potentially switching with elevation.This study provides insights into the underlying assembly mechanisms of mountain amphibians,integrating multidimensional diversity.
基金supported by grants from the Natural Sciences and Engineering Research Council of Canada (NSERC)SaskCanola Funding+1 种基金Saskatchewan Agricultural Development Fund (ADF)Ministry of Agriculture Strategic Research Chair Fund (Saskatchewan,Canada)
文摘In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques： such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals.
基金fully funded by the Natural Science Foundation of Guangdong Province(Grant No.2020A1515011404)Guangxi Major Science and Technology Project(Grant No.AA17204087-9)+2 种基金Guangdong Forestry SciTech Innovation Platform Project(Grant No.2020-KYXM-09)China National Key R&D Program during the 13th Five-year Plan Period(Grant No.2016YFD0600504)the Operation Project for Guangdong Zhanjiang Eucalyptus Forest Ecosystem National Positioning Observation and Research Station(Grant No.2019132141)。
文摘Multi-generational planting of Eucalyptus species degrades soil quality but the introduction of legumes can improve soil fertility and microbial diversity.However,the effects of introducing non-legume native tree species on soil nutrients and bacterial community structure remain poorly understood.This study investigated the impacts of the conversion of third generation monoculture Eucalyptus plantations to mixed systems including Eucalyptus urograndis with Cinnamomum camphora(EC)and E.urograndis with Castanopsis hystrix(EH),on soil chemical and biochemical properties and bacterial community structure,diversity and functions.First generation E.urophylla plantations were the control.Results show that planting the third generation Eucalyptus led to a significant decrease in p H,organic matter,nutrient content,enzyme activities(invertin,acid phosphataes,and urease),and bacterialα-diversity compare to the controls.However,the mixed planting showed significant improvement in soil chemical and biochemical attributes and bacterialα-diversity,although the E.urograndis and C.hystrix planting had no improvement.Chloroflexi(oligotrophic bacteria)were significantly enriched in third generation Eucalyptus and Eucalyptus+C.hystrix,while proteobacteria increased significantly in the E.urograndis with C.camphora plantings.The relative abundance of multiple metabolic pathways increased significantly in the third generation Eucalyptus plantations whereas membrane transportrelated genes were enriched in soils of the mixed systems.The changes in bacterial community structures in the two mixed systems were driven by diversity,organic matter and acid phosphatase,while bacterial functions were affected by invertase,NO_(3)^(-)-N,diversity and urease.These results suggest that the transformation of successive monoculture Eucalyptus plantations into mixed plantations reduces the depletion of soil nutrients and enhances the ecological function of soil microorganisms.
基金funded by the National Natural Science Foundation of China(Grant Nos.41922016,42130806,41830427 and 41872179).
文摘Wettability affects the immiscible flow process of the gas-water phases in coalbed methane reservoirs,which has an important effect on coalbed methane production.The sessile drop method,infrared spectroscopy and atomic force microscopy(AFM)were used to study the wettability,functional groups and pore structure of 8 coal rocks with middle ranks from the Qinshui Basin,North China,and the Junggar Basin,Northwest China.The pore structure of the coal sample,including the porosity,number of pores,pore area,pore diameter,percentage of different types of pores and roughness under the scale of 50 mm,was determined using the Nanoscope and Gwyddion analysis methods.The relationships between the pore structure,functional groups,coal surface roughness and wettability were studied.The results show that the larger the proportion of macropores on the coal surface is,the stronger the hydrophilicity of coal.The more oxygen-containing functional groups there are,the better the wettability of coal and rock.The contact angle has a sinusoidal relationship with the roughness due to the change in the adsorption point.For coal with very low or very high roughness,the contact angle is negatively correlated with the roughness,while for coal with low to average roughness,the contact angle is significantly positively correlated with the roughness.This work provides new insights into the interactions between water molecules and the coal pore surface.
基金the National Natural Science Foundation of China (Nos.39830310 and 30070134)the NationalKey Basic Research Support Foundation (NKBRSF) of China (No.2002CB111504).
文摘Soil samples were collected from both bare and vegetated mine railings to study the changes in bacterial communities and soil chemical properties of copper mine tailings due to reed （Phragmites communis） colonization. The structures of bacterial communities were investigated using culture-independent 16S rRNA gene sequencing method. The bacterial diversity in the bare mine tailing was lower than that of the vegetated mine tailing. The former was dominated by sulfur metabolizing bacteria, whereas the latter was by nitrogen fixing bacteria. The bare mine tailing was acidic （pH = 3.78）, whereas the vegetated mine tailing was near neutral （pH ： 7.28）. The contents of organic matter, total nitrogen, and ammonium acetate-extractable potassium in vegetated mine tailings were significantly higher than those in the bare mine railings （P 〈 0.01）, whereas available phosphorus and electrical conductivity were significantly lower than those in the bare mine tailings （P 〈 0.01）. The results demonstrated that 16S rRNA gene sequencing could be successfully used to study the bacterial diversity in mine tailings. The colonization of the mine tailings by reed significantly changed the bacterial community and the chemical properties of tailings. The complex interactions between bacteria and plants deserve further investigation.
基金supported by the National Key Research and Development Program of China (No.2016YFD02003096)National Natural Science Foundation of China (Nos.41371296 and 41571219)Young Scientist Group of Northeast Institute of Geography and Agroecology, Chinese Academy of Sciences (No.DLSXZ1605)
文摘It has been well documented that organic amendment affects soil nematode community structure.However,little is known about the effect of organic amendment amount on soil nematodes.To assess the effect of the amount of organic amendments on soil nematode community structure and metabolic activity,the community composition,abundance,and metabolic footprints of soil nematodes were determined in a long-term field experiment with various amounts of organic amendment in Northeast China.Fertilization treatments included an unfertilized control(CK),chemical fertilizer without manure amendment(OM0),manure applied at 7.5 Mg ha^-1 plus chemical fertilizer(OM1),and manure applied at 22.5 Mg ha^-1 plus chemical fertilizer(OM2).A total of 46 nematode genera were found.Treatments with the largest amount of organic amendment had the smallest number of plant parasite genera(5),but a largest number of dominant genera(7).Soil nematodes,bacterivores,and fungivores were the most abundant in OM2,followed by OM1,and the lowest in OM0 and CK.Organic amendment increased the enrichment index(EI),and the large amount of organic amendment increased the metabolic footprints of bacterivore(Baf)and fungivore(Fuf)and enrichment footprint(Ef).The relationships between Baf(or Fuf)and the increases in soil organic carbon(?SOC)and total nitrogen(?TN)were stronger than those of bacterivore(or fungivore)abundance with?SOC and?TN,except for the relationship between bacterivore abundance and ?SOC.The EI and Ef were positively correlated with ?SOC and ?TN.These findings suggest that the amount of organic amendment affects soil nematode activity and function at entry levels in soil food web,and that metabolic footprints of soil nematodes may be better indicators than their abundances in assessing their relationships with soil nutrients.
基金This study was supported by the National Key Research and Development Program of China(2016YFC0500503 and 2016YFC0500501)by the Department of Science and Technology of Inner Mongolia Autonomous Region for studying steppe ecosystems on the Mongolian Plateau(20140409 and 201503001).
文摘Aims Functional group composition of a plant community is mainly driven by environmental factors and is one of the main determinants of grassland biodiversity and productivity.Therefore,it is important to understand the role of plant functional groups(PFGs)in mediating the impact of environmental conditions on ecosystem functions and biodiversity.Methods We measured plant biomass and species richness(SR)of grasslands in 65 sites on the Mongolian Plateau and classified 157 perennial herbaceous plants into two main PFGs(namely grasses and forbs).Using the random forest model and ordinary least squares regression,we identified that environmental factors(i.e.aridity index,soil total nitrogen[STN]and pH)were significantly related to the SR and aboveground biomass(AGB)of PFGs.We then used structural equation modeling to explore the relationship between the identified environmental factors and community SR and biomass,and the role of PFGs in driving this relationship.Important Findings We found that aridity index had unimodal relationships with both AGB and SR of the PFGs and the whole community.All SR and biomass metrics were significantly related to STN and pH.The relationship between aridity index and community biomass was mediated by an increase in the AGB of grasses.The influence of STN and pH on community SR was mainly due to their regulation in the SR of forbs.Our results indicate that community composition and the identity of the PFGs play a key role in linking environmental factors to ecosystem functioning.
基金supported through funding from CSIRO Business Unit Agriculture&Food,MOSH-Future Science Platform in Australia,and Michigan State University in the USA.J.T.was also supported by a CSIRO McMaster fellowship when in Adelaide,Australia,and by the US Department of Energy Office of Science,awards DE-FC02-07ER6449 and DE-FG02-99ER62848the US National Science Foundation Award DBl-1759892.
文摘The incredibly complex soil microbial communities at small scales make their analysis and identification of reasons for the observed structures challenging.Microbial community structure is mainly a result of the inoculum(dispersal),the selective advantages of those organisms under the habitat-based environmental attributes,and the ability of those colonizers to sustain themselves over time.Since soil is protective,and its microbial inhabitants have long adapted to varied soil conditions,significant portions of the soil microbial community structure are likely stable.Hence,a substantial portion of the community will not correlate to often measured soil attributes.We suggest that the drivers be ranked on the basis of their importance to the fundamental needs of the microbes:(i)those that supply energy,i.e.,organic carbon and electron acceptors;(i)environmental effectors or stressors,i.e.,pH,salt,drought,and toxic chemicals;(ii)macro-organism associations,i.e.,plants and their seasonality,animals and their fecal matter,and soil fauna;and(iv)nutrients,in order,N,P,and probably of lesser importance,other micronutrients,and metals.The relevance of drivers also varies with spatial and time scales,for example,aggregate to field to regional,and persistent to dynamic populations to transcripts,and with the extent of phylogenetic difference,hence phenotypic differences in organismal groups.We present a summary matrix to provide guidance on which drivers are important for particular studies,with special emphasis on a wide range of spatial and temporal scales,and illustrate this with genomic and population(rRNA gene)data from selected studies.
基金This work was supported in part by the Knowledge Innovation Engineering Action,the Chinese Academy of Sciences(KZCX2-SW-416)the National Natural Science Foundation of China(Grant No.20225722).
文摘The potential ecotoxicologial risks of methamidophos,copper,and their combinations on microbial community of black soil ecosystem in the Northeast China were assessed in species richness and structures by using 16S rDNA-PCR-DGGE analysis approach,and functional characteristics at community levels by using BIOLOG^(GN) system analysis method as well as two conventional methods(DHA and SIR).All results of DGGE banding fingerprint patterns(amplified by bacterial specific 16S rDNA V_(3) high variable region universal primer)indicated that the species richness of bacterial community in tested soil was significantly decreased to different extents by using different concentrations of single methamidophos,copper,especially some of their combinations had worse effects than their corresponding single factors.In addition,the structures of soil bacterial community had been disturbed under all stresses applied in this study because of the enrichment of some species and the disappearance of other species from the bacterial community.The effects of the single factors with lower concentrations on the communiy structure were weaker than those with higher concentrations.Moreover,the bacterial community structures under the combined stresses of methamidophos and copper were significantly different from those of control and their corresponding single factors.The change of DHA and carbon source substrate utilizing fingerprint patterns based on BIOLOG^(GN)system were two relatively sensitive directors corresponding to the stress presented in this study.Between methamodophos and copper,there happened the significant joint-toxic actions when they were used in combination on DHA and carbon source substrate utilizing fingerprint patterns of soil bacterial communities.The DHA of soil under the combined stresses was lower than that of the control and that under the single factors,and the BIOLOG^(GN) substrate utilizing patterns of soil treated by combinations were distinctively differentiated from the control and their corresponding single factors.From all of above,the methamidophos,copper,especially their combinations had the clearly potential ecotoxicological risks to influence the natural soil microbial ecological system by changing the structure,richness,and the functional characteristics of microbial community.
基金supported by the National Key Research and Development Program of China(No.2019YFC0408500)the Scientific Research Project of China State Construction Engineering Corporation Limited(CSCEC-2022-K-(36))the Scientific Research Project of CSCEC AECOM Consultants Corporation Limited(XBSZKY2216).
文摘Anaerobic digestion(AD),as an eco-friendly biological process,shows potential for the decomposition of leachate produced by waste incineration power plants.In this study,the effects of Fe oxides nano-modified pumice(FNP)were investigated on the fresh leachate AD process.Firstly,a simple hydrothermal method was used to prepare FNP,then introduced into the UASB reactor to evaluate its AD efficiency.Results showed that the inclusion of FNP could shorten the lag phase by 10 days compared to the control group.Furthermore,cumulative methane production in the FNP group was enhanced by 20.11%.Mechanistic studies suggested that hydrogenotrophic methanogenesis in the FNP group was more pronounced due to the influence of key enzymes(i.e.,dehydrogenase and coenzyme F420).Microbial community analysis demonstrated that FNP could enhance the abundance of Methanosarcina,Proteobacteria,Sytrophomonas,and Limnobacter,which might elevate enzyme activity involved in methane production.These findings suggest that FNP might mediate interspecies electron transfer among these microorganisms,which is essential for efficient leachate treatment.
基金the National Natural Science Foundation of China(NSFC)(Grant No.31560063)Applied Basic Research Program of Yunnan Province,China(2018FB067).
文摘Few studies have examined the succession of plant communities in the alpine zone.Studying the succession of plant communities is helpful to understand how species diversity is formed and maintained.In this study,we used species inventories,a molecular phylogeny,and trait data to detect patterns of phylogenetic and functional community structure in successional plant communities growing on the mounds of Himalayan marmots(Marmota himalayana)on the southeast edge of the Qinghai-Tibet Plateau.We found that phylogenetic and functional diversities of plant communities on marmot mounds tended to cluster during the early to medium stages of succession,then trended toward overdispersion from medium to late stages.Alpine species in early and late stages of succession were phylogenetically and functionally overdispersed,suggesting that such communities were assembled mainly through species interactions,especially competition.At the medium and late stages of succession,alpine communities growing on marmot mounds were phylogenetically and functionally clustered,implying that the communities were primarily structured by environmental filtering.During the medium and late stages of succession the phylogenetic and functional structures of plant communities on marmot mounds differed significantly from those on neighboring sites.Our results indicate that environmental filtering and species interactions can change plant community composition at different successional stages.Assembly of plant communities on marmot mounds was promoted by a combination of traits that may provide advantages for survival and adaptation during periods of environmental change.
基金National Science Foundation for Excellent Young Scholars of China (21922815)Key Research and Development (R&D) Projects of Shanxi Province (201903D121007)+3 种基金Natural Science Foundations of Shanxi Province (201801D221156)DNL Cooperation Fund of CAS (DNL180308)Science and Technology Service Network Initiative of CAS (KFJ-STS-ZDTP-068)Youth Innovation Promotion Association of CAS。
文摘The presence of oxygen functional groups is detrimental to the capacitive performance of porous carbon electrode in organic electrolyte. In this regards, hydrogen thermal reduction has been demonstrated effective approach in removing the unstable surface oxygen while maintaining the high porosity of carbon matrix. However, the exact evolution mechanism of various oxygen species during this process, as well as the correlation with electrochemical properties, is still under development. Herein, biomass-based porous carbon is adopted as the model material to trace its structure evolution of oxygen removal under hydrogen thermal reduction process with the temperature range of 400–800 °C. The optimum microstructure with low oxygen content of 0.90% and proper pore size distribution was achieved at 700°C. XPS, TPRMS and Boehm titration results indicate that the oxygen elimination undergoes three distinctive stages(intermolecular dehydration, hydrogenation and decomposition reactions). The optimum microstructure with low oxygen content of 0.90% and proper pore size distribution was achieved at 700 °C. Benefiting from the stable electrochemical interface and the optimized porous structure, the as-obtained HAC-700 exhibit significantly suppressed self-discharge and leak current, with improved cycling stability, which is attributable to the stabilization of electrochemical interface between carbon surface and electrolyte. The result provides insights for rational design of surface chemistry for high-performance carbon electrode towards advanced energy storage.
基金National Natural Science Foundation of China (42107376)the earmarked fund for China Agriculture Research System (CARS-13)。
文摘Improving soil quality while achieving higher productivity is the major challenge in the agricultural industry. Wheat(Triticum aestivum L.)–maize(Zea mays L.)(W–M) rotation is the dominant planting pattern in the Huang-HuaiHai Plain and is important for food security in China. However, the soil quality is deteriorating due to the W–M rotation’s long-term, intensive, and continuous cultivation. Introducing legumes into the W–M rotation system may be an effective way to improve soil quality. In this study, we aimed to verify this hypothesis by exploring efficient planting systems(wheat–peanut(Arachis hypogaea L.)(W–P) rotation and wheat rotated with maize and peanut intercropping(W–M/P)) to achieve higher agricultural production in the Huang-Huai-Hai Plain. Using traditional W–M rotation as the control, we evaluated crop productivity, net returns, soil microorganisms(SMs), and soil organic carbon(SOC) fractions for three consecutive years. The results indicated that wheat yields were significantly increased under W–P and W–M/P(382.5–579.0 and 179.8–513.1 kg ha-1, respectively) compared with W–M. W–P and W–M/P provided significantly higher net returns(58.2 and 70.4%, respectively) than W–M. W–M/P and W–M retained the SOC stock more efficiently than W–P, increasing by 25.46–31.03 and 14.47–27.64%, respectively, in the 0–20 cm soil layer. Compared with W–M, W–M/P improved labile carbon fractions;the sensitivity index of potentially mineralizable carbon, microbial biomass carbon(MBC), and dissolved organic carbon was 31.5, 96.5–157.2, and 17.8% in 20–40, 10–40, and 10–20 cm soil layers, respectively. The bacterial community composition and bacteria function were altered as per the soil depth and planting pattern. W–M/P and W–M exhibited similar bacterial community composition and function in 0–20 and 20–40 cm soil layers. Compared with W–P, a higher abundance of functional genes, namely, contains mobile elements and stress-tolerant, and a lower abundance of genes, namely,potentially pathogenic, were observed in the 10–20 cm soil layer of W–M and the 0–20 cm soil layer of W–M/P. SOC and MBC were the main factors affecting soil bacterial communities, positively correlated with Sphingomonadales and Gemmatimonadales and negatively correlated with Blastocatellales. Organic input was the main factor affecting SOC and SMs, which exhibited feedback effects on crop productivity. In summary, W–M/P improved productivity, net returns, and SOC pool compared with traditional W–M rotation systems, and it is recommended that plant–soil–microbial interactions be considered while designing high-yield cropping systems.
文摘为了系统探讨煤自燃倾向性的影响因素,基于逐步回归分析方法,提出以煤样的工业分析参数、孔隙结构参数、官能团含量和燃烧活化能为自变量,燃点温度为因变量预测煤自燃模型,揭示煤自燃特性与微观结构间的关联。结果表明:6个煤样的孔隙分形维数平均值为2.770,孔隙结构较为复杂,煤氧反应时可以提供更多的吸附位点;XL3的燃点温度最低为486℃,燃烧活化能也最低,为82.01 k J/mol;燃点温度y=381.152-1.494S_(BET)+21.550I_(C-O),R^(2)=0.998,表明了BET比表面积和C—O峰强度可以解释燃点温度99.8%变化的原因,且C—O峰强度对燃点温度的影响更为显著。研究结果揭示了煤体孔隙比表面积与含氧官能团是控制自燃倾向性的核心因素,为煤自燃风险评估提供了理论依据。
基金Supported by National Natural Science Foundation of China (31270740)Natural Science Foundation of Hubei Province (2017CFB390)。
文摘[Objectives]This study was conducted to analyze species composition, community appearance, plant life-type spectrum, flora distribution, plant community structure and plant diversity indexes of Mingyue Park in Jingzhou City, as well as the ecological functions of plants in cooling, humidification, shading, and noise reduction. [Methods] A quadart method was used to investigate plant communitues of Mingyue Park in Jingzhou City. [Results] There were 141 species in the park, including 44 tree speceies, 35 shrub speceies, and 62 herb speceies. The arber-shrub-grass structure was the dominant plant community structure. The Simpson index(D), Shannon-Wiener index(H) and Pielou index(J) of the herb layer were higher than those of the tree layer and the shrub layer, and the shrub layer was the lowest. The results of ecological function research showed that the plant communities had a significant shading effect and a certain ability to reduce noise. The comprehensive conclusion showed that the ecological function indexes of the arbor-shrub-grass structure in Mingyue Park were significantly higher than those of the arbor-shrub structure and the single-tree structure. In order to improve the ecological benefits of plant communities in Mingyue Park, the plant diversity can be increased in the later construction to enrich community structures. [Conclusions] This study evaluated the ecological benefits of plant communities in Mingyue Park, and provides a scientific basis for the plant configuration of parks in Jingzhou and other regions.
