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Elevational patterns of warming effects on plant community and topsoil properties: focus on subalpine meadows ecosystem

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Journal of Mountain Science 2024年第1期21卷 146-159页

作者： HAO Aihua LUO Zhengming CHEN Xiaojiang Department of Geography Xinzhou Normal UniversityXinzhou 034000China Department of Biological Sciences Xinzhou Normal UniversityXinzhou 034000China

Climate warming profoundly affects plant biodiversity, community productivity, and soil properties in alpine and subalpine grassland ecosystems. However, these effects are poorly understood across elevational gradients in subalpine meadow ecosystems. To reveal the elevational patterns of warming effects on plant biodiversity, community structure, productivity, and soil properties, we conducted a warming experiment using open-top chambers from August 2019 to August 2022 at high(2764 m a. s. l.), medium(2631 m a. s. l.), and low(2544 m a. s. l.) elevational gradients on a subalpine meadow slope of Mount Wutai, Northern China. Our results showed that three years of warming significantly increased topsoil temperature but significantly decreased topsoil moisture at all elevations(P<0.05), and the percentage of increasing temperature and decreasing moisture both gradually raised with elevation lifting. Warming-induced decreasing proportions of soil organic carbon(SOC, by 19.24%), and total nitrogen(TN, by 24.56%) were the greatest at high elevational gradients. Experimental warming did not affect topsoil C: N, p H, NO_(3)^(-)-N, or NH_(4)^(+)-N at the three elevational gradients. Warming significantly increased species richness(P<0.01) and Shannon-Weiner index(P<0.05) at low elevational gradients but significantly decreased belowground biomass(P<0.05) at a depth of 0–10 cm at three elevational gradients. Warming caused significant increases in the aboveground biomass in the three elevational plots. Warming significantly increased the aboveground biomass of graminoids in medium(by 92.47%) and low(by 98.25%) elevational gradients, that of sedges in high(by 72.44%) and medium(by 57.16%) elevational plots, and that of forbs in high(by 75.88%), medium(by 34.38%), and low(by 74.95%) elevational plots. Species richness had significant linear correlations with SOC, TN, and C: N(P<0.05), but significant nonlinear responses to soil temperature and soil moisture in the warmed treatm

关键词： Warming effect Plant diversity pattern Community structure change Elevation gradient Alpine meadow ecosystem Mount Wutai

Small-sized Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C for efficient alkaline and acidic hydrogen evolution reaction by an anchoring calcination strategy

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Frontiers of Chemical Science and Engineering 2024年第5期18卷 95-103页

作者： Jianxia Gu Ying Zhu Haiyan Zheng Chunyi Sun Zhongmin Su Department of Chemistry Xinzhou Normal UniversityXinzhou 034000China School of Chemistry Northeast Normal UniversityChangchun 130024China

A novel,cheap and highly efficient Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen *** in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions,which avoids the aggregation of catalyst particles during the pyrolysis *** optimization,the obtained Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C possesses small size(3-8 nm),large specific surface area and hierarchical pore *** importantly,Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L^(-1)H_(2)SO_(4)(102.3 mV)and 1 mol·L^(-1)KOH(95 mV)to afford the current density of 10 mA·cm^(-2),as well as small Tafel slopes of 82.49 and 99.92 mV·dec^(-1),***,this catalyst also shows outstanding stability for 12 h without a significant change in current *** excellent catalytic performance of Ni-Co/Mo_(2)C/Co_(6)Mo_(6)C_(2)@C can put down to the synergistic effect between multiple components and the small size of the *** work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.

关键词： polyoxometallates layered double hydroxide transition metal-based electrocatalysts hydrogen evolution reaction

Rayleigh-like distribution of particle transverse momenta in collisions at high energies

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Chinese Physics C 2010年第7期34卷 964-971页

作者：邵贵成李惠玲 Department of Physics Xinzhou Normal University Department of Physics Shanxi Normal University

The transverse momentum distributions of final-state particles produced in collisions at high en-ergies are studied by using a two-component Rayleigh-like *** representation is based on Liu＇s multisource ideal gas model which describes protons and fragments in high energy nucleus-nucleus *** calculated results are in good agreement with the experimental data of Au-Au,Cu-Cu,d-Au,and pp collisions at the relativistic heavy ion collider *** experimental particle momentum distributions of p-Be collisions at 6.4,12.3,and 17.5 GeV/c,as well as Au-Au collisions at 1.5 AGeV are well described by a model based on a single Rayleigh-like distribution of particle transverse momenta.

关键词： transverse momentum distribution Rayleigh-like distribution high energy collisions

Multiparticle azimuthal correlations in central nucleus-nucleus collisions at high energy

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Chinese Physics C 2010年第3期34卷 340-343页

作者：邵贵成 Department of Physics and Electronic Xinzhou Normal University

Multiparticle azimuthal correlations in central nucleus-nucleus collisions at high energy are described by a simple formula. The calculated results are in agreement with the experimental data of carbon and oxygen induced interactions at Dubna energy. The comparison between the calculated results and experimental data shows that particles are emitted isotropically in the rest frame of the emission sources, and the emission sources have movements in momentum space.

关键词： Dubna energy nucleus-nucleus collisions multiparticle azimuthal correlation

Daily SPEI Reveals Long-term Change in Drought Characteristics in Southwest China

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Chinese Geographical Science 2018年第4期28卷 680-693页

作者： JIA Yanqing ZHANG Bo MA Bin College of Geography and Environmental Science Northwest Normal University Department of Geography Xinzhou Normal University

Drought is the most widespread and insidious natural hazard, presenting serious challenges to ecosystems and human society. The daily Standardized Precipitation Evapotranspiration Index(SPEI) has been developed to identify the regional spatiotemporal characteristics of drought conditions from 1960 to 2016, revealing the variability in drought characteristics across Southwest China. Daily data from142 meteorological stations across the region were used to calculate the daily SPEI at the annual and seasonal time scale. The Mann-Kendall test and the trend statistics were then applied to quantify the significance of drought trends, with the following results. 1) The regionally averaged intensity and duration of all-drought and severe drought showed increasing trends, while the intensity and duration of extreme drought exhibited decreasing trends. 2) Mixed(increasing/decreasing) trends were detected, in terms of intensity and duration, in the three types of drought events. In general, no evidence of significant trends(P < 0.05) was detected in the drought intensity and duration over the last 55 years at the annual timescale. Seasonally, spring was characterized by a severe drought trend for all drought and severe drought conditions, while extreme drought events in spring and summer were very severe. All drought intensities and durations showed an increasing trend across most regions, except in the northwestern parts of Sichuan Province. However, the areal extent of regions suffering increasing trends in severe and extreme drought became relatively smaller. 3) We identified the following drought hotspots: Guangxi Zhuang Autonomous Region from the 1960 s to the 1990 s, respectively. Guangxi Zhuang Autonomous Region and Guizhou Province in the 1970 s and 1980 s, and Yunnan Province in the 2000 s. Finally, this paper can benefit operational drought characterization with a day-to-day drought monitoring index, enabling a more risk-based drought management strategy in the conte

关键词： drought spatial-temporal characteristics variability daily Standardized Precipitation Evapotranspiration Index (SPEI) Southwest China

Synthesis and Crystal Structure of Complex: [Co（cdm）2（H2O）4].2H2O （cdm=Carbamyldicyanomethanide Anion）

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Chinese Journal of Structural Chemistry 2002年第2期21卷 178-181页

作者： SHI Jing-Min②1 YIN Hai-Liang1 SUN Li-Jing1 YU Wen-Tao2 XU Wen1 ZHAO Ming-Gen3 1(Department of Chemistry, Shandong normal University, Jinan 250014, China) 2(institute of Crystal Matrials, Shandong University, Jinan 250010, China) 3(Department of Che Shandong normal Univ Dept Chem Jinan 250014 Peoples R China Shandong Univ Inst Crystal Mat Jinan 250010 Peoples R China xinzhou normal inst Dept Chem Xinzhou 034000 Peoples R China

Mononuclear complex [Co(cdm)2(H2O)4]?H2O was synthesized by sodium carbamyldicyanomethanide (Nacda) and cobalt perchlorate. The crystal belongs to monoclinic system, space group P21/n with a = 9.366(3), b = 7.392(3), c = 12.039(4)? = 108.335(4)? V = 791.2(5)?, Z = 2, Mr (C8H16CoN6O8) = 383.2, Dc = 1.608 g/cm3, F(000) = 394, = 1.135 mm-1, = 0.71073 ? The structure was refined to R = 0.0240 and wR = 0.0632 for 1267 observed reflections (I > 2(I)). The cobalt(II) atom in the complex is coordinated by two nitrile-nitrogen atoms and four oxygen atoms of H2O, which forms a slightly distorted coordination octahedron around the cobalt(II) ion. The mononuclear complexes are connected by hydrogen bondings and in the crystal there exists a cavity where the uncoordinated H2O molecules are trapped.

关键词： synthesis crystal structure cobalt complex

Seasonal Changes in Soil Respiration with An Elevation Gradient in Abies nephrolepis(Trautv.)*** in North China

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Phyton-International Journal of Experimental Botany 2022年第7期91卷 1543-1556页

作者： Zhijie Tian Xueying Jia Tingting Liu Eryan Ma Lamei Xue Yanqiu Hu Qingrong Zheng xinzhou Teachers University Xinzhou034000China School of Geography Science Taiyuan Normal UniversityTaiyuan030619China

Soil respiration(Rs)plays an important role in regulating carbon cycle of terrestrial ecosystems and presents temporal and spatial *** nephrolepis is a tree species that prefers the cold and wet environment and is mainly distributed in Northeast Asia and East *** Rs variations of Abies nephrolepis forests communities are generally environmental-sensitive and can effectively reflect the adaptive responses of forest ecosystems to climate *** this study,the growing-seasonal variations of Rs,soil temperature,soil water content and soil properties of Abies nephrolepis forests were analyzed along an altitude gradient(2000,2100,2200 and 2300 m)over two years on Wutai Mountain in North *** the main results showed,soil respiration keeps the same change trend as soil temperature and reached peaks in July at 2000 m in 2019 and *** 26th July to 25th October in 2019 and 27th May to 23rd October in 2020,on the whole,the soil temperature independently explained 76.2%of Rs variations while the soil water content independently explained 26.8%.Soil temperature and soil water content jointly explained 81.8%of Rs *** properties explained 61.8%and 69.6%of Rs variation in 2019 and 2020,*** organic carbon content and soil enzyme activity had the signifi-cant(P<0.01)negative and positive relationships,respectively,with Rs *** altitudes evaluated from 2000 to 2300 m,soil respiration temperature sensitivity(Q10)and the soil organic carbon content increased by 12.4%and 10.4%,respectively,while invertase activity,cellulase activity and urease activity dropped by 41.2%,29.45%and 38.19%,*** results demonstrate that(1)soil temperature is the major factor affecting Rs variations in Abies nephrolepis forests;(2)weakened microbial carbon metabolism in high-altitude areas results in the accumulation of soil organic carbon;(3)with a higher Q10,forest ecosystems in high-altitude areas might be more easily affected

关键词： Soil respiration Abies nephrolepis altitude soil respiration temperature sensitivity soil organic carbon

Emission of Neutral Pions with High Transverse Momenta in A-A and p-p Collisions at Energies Available at the BNL Relativistic Heavy Ion Collider

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Chinese Physics Letters 2010年第5期27卷 58-61页

作者：范三红孟彩荣刘福虎 School of Life Science Shanxi University Taiyuan 030006 Department of Physics Xinzhou Normal University Xinzhou 034000 institute of Theoretical Physics Shanxi University Taiyuan 030006

Invariant neutral pion （π^0） yields in Au-Au and Cu-Cu collisions and invariant π^0 cross sections in p-p collisions are studied in the framework of a two-cylinder model. The considered distributions of neutral pions at the maximum energy of the relativistic heavy ion eollider （RFIIC） have a tail part in the region of high transverse momentum. A two-component distribution based upon the two-cylinder model is used to describe the experimental data of the PHENIX collaboration.

关键词： PIONS ANGULAR momentum (Nuclear physics) HEAVY ion collisions DISTRIBUTION (Probability theory) FORCE & energy RELATIVITY (Physics) CROSS sections (Nuclear physics) SCATTERING

Probabilistic resumable quantum teleportation in high dimensions

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Chinese Physics B 2022年第3期31卷 165-169页

作者： Xiang Chen Jin-Hua Zhang Fu-Lin Zhang Department of Physics School of ScienceTianjin UniversityTianjin 300072China Department of Physics Xinzhou Teacher's UniversityXinzhou 034000China School of Mathematical Sciences Capital Normal UniversityBeijing 100048China

Teleportation is a quantum information process without classical counterparts, in which the sender can disembodiedly transfer unknown quantum states to the receiver. In probabilistic teleportation through a partial entangled quantum channel,the transmission is exact(with fidelity 1), but may fail in a probability and the initial state is destroyed *** propose a scheme for nondestructive probabilistic teleportation of high-dimensional quantum states. With the aid of an ancilla in the hands of the sender, the initial quantum information can be recovered when teleportation fails. The ancilla acts as a quantum apparatus to measure the sender’s subsystem. Erasing the information recorded in it can resume the initial state.

关键词： probabilistic teleportation entanglement successful probability