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Nitrogen addition reduced carbon mineralization of aggregates in forest soils but enhanced in paddy soils in South China

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Ecological Processes 2021年第1期10卷 597-607页

作者： Ruirui Cao longchi Chen Xincun Hou xiaotao lü Haimei li College of landscape Architecture and Forestry Qingdao Agricultural UniversityQingdao 266109China. Huitong Experimental Station of Forest Ecology CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China. Hunan Key laboratory for Structure and Ecosystem Service of Subtropical Forest Huitong National Research Station of Forest EcosystemHuitong 418307China. Research and Development Center for Grasses and Environment Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China.

Background:Despite the crucial role of nitrogen(N)availability in carbon(C)cycling in terrestrial ecosystems,soil organic C(SOC)mineralization in different sizes of soil aggregates under various land use types and their responses to N addition is not well *** investigate the responses of soil C mineralization in different sized aggregates and land use types to N addition,an incubation experiment was conducted with three aggregate-size classes(2000,250,and 53μm)and two land use types(a Chinese fir plantation and a paddy land).Results:Cumulative C mineralization of thelowest in both forest and paddy soils,indicating that soil aggregates enhanced soil C stability and reduced the loss of soil *** C mineralization in all sizes of aggregates treated with N addition decreased in forest soils,but that in microaggregates and thels treated with 100μgNg−***,the effect sizes of N addition on C mineralization of forest soils were below zero,but those of paddy soils were above *** data indicated that N addition decreased SOC mineralization of forest soils but increased that of paddy ***:Soil aggregates play an important role in soil C sequestration,and decrease soil C loss through the increase of soil C stability,regardless of land use types.N addition has different effects on soil C mineralization in different land use *** results highlight the importance of soil aggregates and land use types in the effects of N deposition on the global terrestrial ecosystem C cycle.

关键词： Ultisol land use type Microaggregates Soil organic carbon

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leaf nutrient dynamics and nutrient resorption:a comparison between larch plantations and adjacent secondary forests in Northeast China

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Journal of Plant Ecology 2016年第2期9卷 165-173页

作者： Tao Yan xiaotao lü Kai Yang Jiaojun Zhu State Key laboratory of Forest and Soil Ecology Institute of Applied EcologyChinese Academy of SciencesNo.72 Wenhua RoadShenhe DistrictShenyang 110164China Qingyuan Forest CERN Chinese Academy of SciencesNo.72 Wenhua RoadShenhe DistrictShenyang 110016China University of Chinese Academy of Sciences No.19A Yuquan RoadShijingshan DistrictBeijing 100049China

Aims Conversion of secondary forests to pure larch plantations is a common management practice driven by the increasing demand for timber production in Northeast China,resulting in a reduction in soil nutrient availability after a certain number of years following *** resorption prior to leaf senescence was related to soil fertility,an important nutrient conservation strategy for plants,being especially significant in nutrient-poor ***,the seasonal dynamics of leaf nutrients and nutrient resorption in response to secondary forest conversion to larch plantations is not well *** A comparative experiment between larch plantations(larix spp.)and adjacent secondary forests(dominant tree species including Quercus mongolica,Acer mono,Juglans mandshurica and Fraxinus rhynchophylla)was *** examined the variations in leaf nutrient(macronutrients:N,P,K,Ca and Mg;micronutrients:Cu and Zn)concentrations of these tree species during the growing season from May to October in *** resorption efficiency and proficiency were compared between larix *** the broadleaved species in the secondary *** Findings Results show that the seasonal variation of nutrient concentrations in leaves generally exhibited two trends,one was a downward trend for N,P,K,Cu and Zn,and another was an upward trend for Ca and *** variations in foliar nutrient concentrations were mainly controlled by the developmental stage of leaves rather than by tree *** of the observed seven elements varied among the five tree species during leaf *** resorption efficiency varied 6–75%of N,P,K,Mg,Cu and Zn,while Ca was not retranslocated in the senescing leaves of all species,and Mg was not retranslocated in larix ***,larix *** to be more efficient and proficient(higher than 6–30%and 2–271%of nutrient resorption efficiency and resorption proficiency,respectively)in resorbing nutrients than the broa

关键词： seasonal variation nutrient resorption efficiency soil nutrient availability natural secondary forest larix spp.

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Regenerative Role of Soil Seed Banks of Different Successional Stages in A Saline-alkaline Grassland in Northeast China

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Chinese Geographical Science 2018年第4期28卷 694-706页

作者： MA Hongyuan lI Jingpeng YANG Fan lü xiaotao PAN Yuepeng lIANG Zhengwei Da'an Sodic land Experiment Station Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun 130102China Erguna Forest-Steppe Ecotone Research Station Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesShenyang 110016China State Key laboratory of Atmospheric Boundary layer Physics and Atmospherie Chemistry Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China

Soil seed banks can act as a potential seed source for natural revegetation and restoration. However, in a saline-alkaline grassland, it remains unclear how the stages of vegetation succession affect the characteristics of soil seed banks and the potential of soil seed banks of different successional stages for vegetation restoration. In this study, seasonal changes of the soil seed bank, and seed production and dispersal dynamics along degradation successional gradients were investigated in a saline-alkaline grassland in Northeast China, where the dominant grass during the 1960 s, leymus chinensis was replaced with the secondary successional order of Puccinellia chinampoensis, Chloris virgata, and Suaeda salsa, together with bare patches. It was found that the soil seed bank composition varied according to the changing vegetation and had the highest species richness(7–16) in the climax successional stage, but had a low S?rensen similarity(0.22–0.37) with the aboveground vegetation. There was a high seed density of the soil seed bank(21 062–62 166/m2 in August and December) and also high S?rensen similarity index values(0.47–0.60) in the secondary successional stages of P. chinampoensis, C. virgata, and S. salsa. In bare patches, there were many seeds in the soil seed bank and some seedlings also appeared in the aboveground vegetation, indicating the existence of a persistent soil seed bank. Seed density and species richness differed substantially among the different successional stages, which was related to the reproductive characteristics of the standing plants in vegetation communities. Due to the lack of propagules of perennial species, especially the climax species of l. chinensis, in the soil, the successful restoration of the degraded saline-alkaline grassland was not possible. The study proved that in a degraded saline-alkaline grassland dominated by biennial or annual species, the soil seed bank was important for the revegetation of the current dominant pla

关键词： soil seed bank seed dispersal ecological restoration phenology succession seed rain

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Effects of the frequency and the rate of N enrichment on community structure in a temperate grassland

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Journal of Plant Ecology 2018年第5期11卷 685-695页

作者： Yunhai Zhang Jing Wang Carly J.Stevens xiaotao lü Nianpeng He Changhui Wang Xingguo Han State Key laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesNo.20 NanxincunXiangshanBeijing 100093China lancaster Environment Centre Lancaster UniversityLancaster LA14YQUK Department of Agroecology Aarhus UniversityBlichers Allé20Tjele 8830Denmark University of the Chinese Academy of Sciences No.19 Yuquan RoadShijingshan DistrictBeijing 100049China Erguna Forest-Steppe Ecotone Research Station CAS Key Laboratory of Forest Ecology and ManagementInstitute of Applied EcologyChinese Academy of SciencesNo.72 Wenhua RoadShenhe DistrictShenyang 110016China Synthesis Research Center of Chinese Ecosystem Research Network Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of Sciences11ADatun RoadChaoyang DistrictBeijing 100101China

Aims Nitrogen(N)enrichment caused by human activities threatens bio-diversity and alters plant community composition and *** has been found that heavy and infrequent N inputs may over-estimate species extinction,but it remains unclear whether plant community structure will equally respond to frequent reactive N enriched *** We independently manipulated the rates and the frequencies of N addition in a temperate steppe,northern China,between 2008 and *** Findings We found that plant community structure changes,measured by‘Euclidean distance’involving species richness,composition and productivity,were significantly positively related to increasing N enrichment rates rather than *** in aboveground net primary productivity(ANPP),plant species richness and shifts in dominant species were *** ANPP increased with N enrichment,whereas species richness *** frequency of N enrichment increased species richness but had no impacts on community ANPP and the relative ANPP of the two dominant spe-cies,C3 perennial bunchgrass Stipa grandis and C3 perennial rhi-zome grass leymus *** ANPP and relative ANPP of the two dominant species were significantly negatively correlated with each ***,changes in the relative ANPP of *** was negatively associated with the changes in community *** 5 years’treatment,direct influence of the frequency of N en-richment on plant community structure was not observed,but the effects of the rate of N enrichment were *** results sug-gested that further study in various ecosystems and with long-term and well-controlled comparisons the frequency *** rate of N enrichment may still be needed.

关键词： biodiversity dominance effect nitrogen addition frequency nitrogen deposition productivity

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Variations in leaf carbon isotope composition along an arid and semi-arid grassland transect in northern China

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Journal of Plant Ecology 2016年第5期9卷 576-585页

作者： Chao Wang Dongwei liu Wentao luo Yunting Fang Xiaobo Wang xiaotao lü Yong Jiang Xingguo Han Edith Bai Key laboratory of Forest Ecology and Management Institute of Applied EcologyChinese Academy of SciencesShenyang 110164China

Aims We aimed to quantify the variation of leafδ^(13)C along an arid and semi-arid grassland transect in northern *** also evaluated the effects of environmental factors(***,temperature and altitude)on the spatial variation of leafδ^(13)C in northern grasslands and Tibetan Plateau,*** We sampled leaves of plant species belonging to three herb genera(Stipa spp.,leymus *** Cleistogenes spp.)and three shrub genera(Caragana spp.,Reaumuria *** Nitraria spp.)for carbon isotope analysis from 50 locations along a 3200-km arid and semiarid grassland transect in northern ***δ^(13)C data in Tibetan Plateau and northern grasslands in China were also compiled from studies in *** Findings Along the transect,leafδ^(13)C for C_(3)plants ranged from−28.0‰to−23.3‰,and from−16.3‰to−13.8‰for C_(4)plant Cleistogenes spp..The change in leafδ^(13)C ranged from−0.26‰to−3.51‰with every 100 mm increase of annual precipitation,and leafδ^(13)C of shrubs(Nitraria spp.,Reaumuria *** Caragana spp.)responded more markedly to climatic factors(precipitation and temperature)than that of herbs(Stipa spp.,leymus *** Cleistogenes spp.),indicating higher sensitivity of shrubδ^(13)C to climatic *** most important factor regulating spatial variations of leafδ^(13)C in Tibetan Plateau was altitude,while it was precipitation in northern *** results suggested that shrubs are more adapted to increasing drought in arid and semi-arid *** of environmental factors on leafδ^(13)C depended on the most limiting factors in arid grassland(precipitation)and Tibetan grasslands(atmospheric CO_(2)concentration).

关键词： carbon isotope water use efficiency plant life-form rainfall gradient climate change

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Controllable Exciton Diffusion length and Ultrafast Charge Generation in Ternary Organic Solar Cells

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Chinese Journal of Chemistry 2024年第11期42卷 1275-1283页

作者： Sixuan Cheng Jiawei Qiao Peng lu Wei Qin xiaotao Hao School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinanShandong250100 China School of Physics National Demonstration Center for Experimental Physics EducationShandong UniversityJinanShandong250100 China ARC Centre of Excellence in Exciton Science School of ChemistryThe University of MelbourneParkvilleVictoria3010 Australia

Charge generation,a critical process in the operation of organic solar cell(OSC),requires thorough investigation in an ultrafast *** work demonstrates that the utilization of alloy model for the non-fullerene acceptor(NFA)component can regulate the crystallization properties of active layer films,which in turn affects exciton diffusion and hole transfer(HT),ultimately influencing the charge generation *** incorporating BTP-eC7 as a third component,without expanding absorption range or changing molecular energy levels but regulating the ultrafast exciton diffusion and HT processes,the power conversion efficiency(PCE)of the optimized PM6:BTP-eC9:BTP-eC7 based ternary OSC is improved from 17.30%to 17.83%,primarily due to the enhancement of short-circuit current density(JSC).Additionally,the introduction of BTP-eC7 also reduces the trap state density in the photoactive layer which helps to reduce the loss of *** study introduces a novel approach for employing ternary alloy models by incorporating dual acceptors with similar structures,and elucidates the underlying mechanism of charge generation and JSC in ternary OSCs.

关键词： Organic photovoltaics Ternary strategy Exciton diffusion Hole transfer Trap state Kinetics Alloys Photophysics

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Supertetragonal BaZrS_(3):A promising perovskite sulphide with giant ferroelectricity and low band gap

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Science China(Physics,Mechanics & Astronomy) 2024年第8期67卷 126-133页

作者： Menglu li Sa Zhang Chenhan liu xiaotao Zu liang Qiao Haiyan Xiao School of Physics University of Electronic Science and Technology of ChinaChengdu 611731China College of Mathematics and Physics Chengdu University of TechnologyChengdu 610059China Micro-and Nano-scale Thermal Measurement and Thermal Management laboratory Ministry of Education Key Laboratory of Numerical Simulation of Large-Scale Complex SystemsSchool of Energy and Mechanical EngineeringNanjing Normal UniversityNanjing 210023China

Over the past century,ferroelectricity has offered exciting opportunities for fundamental research and device ***,most of the discovered excellent ferroelectrics are oxide materials with large band gaps,limiting their potential for optoelectronics *** using first-principles calculations we identify a new narrow-gap ferroelectric beyond oxides,i.e.,ferroelectric perovskite sulphide BaZrS_(3).Under large compressive strains,BaZrS_(3)can be stabilized into a unique supertetragonal phase with an extraordinary polarization of 67.16μC/cm^(2),which is even stronger than that of conventional oxide ***,the supertetragonal BaZrS_(3)exhibits a direct narrow band gap of 1.2 eV and excellent electronic *** on the chemical bonding analysis,we attribute the formation of supertetragonal phase to charge re-ordering in which theπbond overlap along the long〈Zr-S〉bond completely vanishes and the antibonding states of theσbond appear below the Fermi *** work provides a conceptual strategy for designing new ferroelectrics for electronic and photovoltaic applications.

关键词： supertetragonal phase perovskite sulphide ferroelectricity

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Percarbonate activation catalyzed by nanoblocks of basic copper molybdate for antibiotics degradation: High performance, degradation pathways and mechanism

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Chinese Chemical letters 2024年第10期35卷 401-404页

作者： xiaotao Jin Yanlan Wang Yingping Huang Di Huang Xiang liu Engineering Research Center of Eco-Environment in Three Gorges Reservoir Region of Ministry of Education College of Materials and Chemical EngineeringChina Three Gorges University Department of chemistry and chemical engineering Liaocheng University

Sodium percarbonate（Na2CO3·1.5H2O2, SPC） has been extensively employed as a solid substitute of H2O2for Fenton process in water treatment, because of its high stability during the production, transport, storage and usage. In addition, SPC can be applied in a wider range of work pH, it is also applied as a buffer in Fenton reaction for preventing a drop in pH. Herein, we have synthesized basic copper molybdate（BCM） nanoblocks with the molecular formula of Cu3（MoO4）2（OH）2as an efficient and heterogeneous catalyst for antibiotics degradation via percarbonate activation. First, fully physical characterizations confirmed BCM nanocomposite exhibited a structure of nanoblocks. We also found that BCM/SPC system could work in a much wider pH range, compared with H2O2. Then, BCM/SPC system presented a good anti-interference ability for natural organic matter in OTC degradation. EPR results and Quenching tests confirmed that the co-presence of·CO3-,·O2-,1O2and·OH in BCM/SPC system.

关键词： Copper molybdate Fenton process Nanoblocks Sodium percarbonate Water treatment

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Atmospheric iron deposition in a megacity of northwest China:Solubility,speciation,and deposition fluxes

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Particuology 2024年第7期90卷 383-393页

作者： xiaotao Yang Pingping liu Zhiwei Xue Hao Zhang Xuan li Hongmei Xu Zhenxing Shen Department of Environmental Science and Engineering Xi'an Jiaotong UniversityXi'anChina State Key laboratory of loess and Quaternary National Key R&D of China Geology Institute of Earth EnvironmentChinese Academy of SciencesXi'anChina No.203 Research Institute of Nuclear Industry Xi'an710086China Xi'an Environmental Monitoring Station Xi'an 710054China

Atmospheric iron has crucial effects on biogeochemical cycles,atmospheric processing,global climate,and human *** this study,atmospheric dustfall samples were collected from six functional areas in Xi'an,China,from 2020 to *** spatiotemporal distributions and deposition fluxes of total and water-soluble(ws)Fe as well as the speciation and potential sources of ws-Fe were *** areas had the highest concentrations of total Fe and ws-Fe,which were mainly due to copious emissions of heavy metals during *** total Fe concentrations peaked in spring,primarily due to the substantial input of crustal dust,which also led to the lowest Fe solubility in this *** contrast,the highest levels of ws-Fe occurred during winter due to an increase in biomass *** the water-soluble forms,ws-Fe(II)was dominant and accounted for 74.8%of the total amount of *** dust was the main contributor to total Fe,whereas biomass burning primarily contributed to peak ws-Fe *** average total and ws-Fe deposition fluxes in Xi'an were the highest in spring and lowest in autumn,which were related to the distributions of the dustfall deposition fluxes and their Fe contents during these *** study provided a broader and comprehensive understanding of atmospheric iron deposition in Chinese urban area,which is of positive significance for understanding atmospheric chemistry and global climate change.

关键词： Atmospheric dustfall Iron Speciation distribution Seasonal variation Functional area Sources

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Epidemiological Characterization of Dengue Fever—Yunnan Province,China,2010-2021

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China CDC weekly 2024年第20期6卷 457-462,I0002-I0007页

作者： Xiaoxiang Zhu Songwang Wang Yanfei li Yu Cao Xuemei Su xiaotao Zhao National Key laboratory of Intelligent Tracking and Forecasting for Infectious Diseases Chinese Center for Disease Control and PreventionBeijingChina Yunnan Institute of Parasitic Diseases Pu’er CityYunnan ProvinceChina

Objective:The goal of this study is to analyze the epidemiological patterns of dengue fever across different districts and counties in Yunnan Province from 2010 to ***:In this study,we employed joinpoint regression analysis,spatial autocorrelation analysis,and space-time scan analysis to illustrate the spatiotemporal propagation and demographic influence of dengue fever,using both graphical and tabular presentations to clearly demonstrate the ***:Yunnan Province reported 14,098 cases of dengue fever during the period from 2010 to *** these,11,513 cases were caused by local transmission,2,566 were imported internationally,and 19 were inter-provincial *** trends emerged,revealing a surge in incidences during the summer and autumn *** sex ratio of male to female cases was 1:0.88,with a significant majority of 82.00%of cases involving individuals belonging to the age group of *** service workers constituted the most impacted occupational group,forming 20.96%of total cases.A spatio-temporal scan identified significant clustering of dengue fever cases across space and time,with the most pronounced cluster observed in southern Yunnan,primarily between 2015 and ***:Dengue fever in Yunnan Province manifests as biennial outbreaks,underscoring the necessity for increased surveillance,particularly in counties bordering other regions.

关键词： counties district revealing

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