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Relative position of seeds driven the seedling growth are mediated by root-leaf traits

JOURNAL OF PLANT ECOLOGY 2024年第2期17卷 24-35页

作者： Zhu, Jing Wang, Xue-Lin Jin, Xing Jiang, Lan Lin, Hong-Yu Hu, Yang Liu, Jin-Fu he, zhong-sheng Fujian Agr & Forestry Univ Coll Forestry Fuzhou 350002 Peoples R China Fujian Agr & Forestry Univ Key Lab Fujian Univ Ecol & Resource Stat Fuzhou 350002 Peoples R China Zhenjiang Nat Resources & Planning Bur Econ & Technol Dev Zone Branch Zhenjiang 212132 Peoples R China

Variations in plant traits are indicative of plant adaptations to forest environments, and studying their relationships with tree growth provides valuable insights into forest regeneration. The spatial arrangement of plant seeds within the forest litter or soil critically influences the variations of root-leaf traits, thereby affecting the adaptive strategies of emerging seedlings. However, our current understanding of the impacts of individual root-leaf traits on seedling growth in different relative position, and whether these traits together affect growth, remains limited. This study focuses on the dominant tree species, Castanopsis kawakamii, within the Sanming C. kawakamii Nature Reserve of China. The present experiment aimed to examine the variations in root-leaf traits of seedling, focus on the relative positions of seeds within different layers: beneath or above the litter layer, or within the bare soil layer (without litter). Our findings provided evidence supporting a coordinated relationship between root and leaf traits, wherein leaf traits varied in conjunction with root traits in the relative positions of seeds. Specifically, we observed that seedlings exhibited higher values for specific leaf area and average root diameter, while displaying lower root tissue density. The mixed model explained 86.1% of the variation in root-leaf traits, surpassing the variation explained by the relative positions. Furthermore, soil nitrogen acted as a mediator, regulating the relationship between seedling growth and root-leaf traits, specifically leaf dry matter content and root tissue density. Therefore, future studies should consider artificially manipulating tree species diversity based on root-leaf traits characteristics to promote forest recovery.

关键词： relative growth rate coordination leaf traits root traits soil nitrogen content seed relative positions FUNCTIONAL TRAITS LIFE-HISTORY DISPERSAL MORTALITY DENSITY LITTER STEM

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Leaf litter decomposition dynamics in unmanaged Phyllostachys pubescens stands at high elevations in the Daiyun Mountain National Nature Reserve

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Journal of Mountain Science 2017年第11期14卷 2246-2256页

作者： XU Dao-wei LIU Jin-fu Peter MARSHALL he zhong-sheng ZheNG Shi-qun Cross-strait Nature Reserve Research Center Fujian Agriculture and Forestry University Key Laboratory of Fujian Universities for Ecology and Resource Statistics Faculty of Forestry University of British Columbia

Due to its rapid growth and high rate of spread, Phyllostachys pubescens can suppress other species, eventually leading to pure P. pubescens forests. Research on the patterns of litter decomposition and nutrient release from P. pubescens across stand mixtures are helpful to understand the decomposition and nutrient dynamics during the invasion process. However, little is known for unmanaged conditions at high elevations. Therefore, we studied the decomposition of four litter compositions comprised of different combinations of P. pubescens and Cunninghamia lanceolata foliage for one year to explore the pattern of litter decomposition and nutrient release at the Daiyun Mountain National Nature Reserve. The results show that:(1) the litter decomposed faster with a higher proportion of P. pubescens based on Olson's decay model;(2) the remaining litter compositions followed a trigonometric function model better than Olson'sdecay model and fluctuated periodically in tandem with changing temperature and precipitation;(3) the litter mixture decompositions did not support the biomass-ratio hypothesis test; and(4) there were significant binomial, power and exponential relationships between initial concentration and final amounts remaining after 1 year decomposition for C, N and P. The correlations between litter decomposition and nutrient releases were significant. The results may be used to explain the rapid spread of P. pubescens and to guide the natural management of plantations.

关键词： Decomposition models Biomass-ratiohypothesis Nutrient release pattern Phyllostachyspubescens Litter decomposition

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Ecological Species Groups and Interspecific Association of Dominant Tree Species in Daiyun Mountain National Nature Reserve

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Journal of Mountain Science 2015年第3期12卷 637-646页

作者： SU Song-jin LIU Jin-fu he zhong-sheng ZheNG Shi-qun HONG Wei XU Dao-wei Fujian Agriculture and Forestry University Fujian Sanming Forest School Cross-Strait Nature Reserve Research Centre Fujian Agriculture and Forestry University

Abstract： Research on the ecological species groups and interspecific association of plant species are helpful to discover species coexistence processes and mechanisms, and to more fully understand plant community structure, function, and its taxonomy. However, little is known about the ecological species groups （ESG） and the interspecific association of dominant species in Daiyun Mountain National Nature Reserve of Fujian Province, China. Therefore, the main goal of this paper is to explore the ESG using maximal tree, and to analyze interspecific associations of 32 dominant species selected from lo2 sample plots using the chi-square test. The results show that：（1） 32 dominant species have a significant overall positive interspecific association, which indicates that the natural forest in Daiyun Mountain National Nature Reserve is stable, （a） The species pairs with weak associations, non-associations and positive associations account for lo.88%, 29.64% and 59.48% of the total 496 species pairs respectively, which suggests that the population distributions of the dominant species investigated are relatively independent, （3） The following species pairs may be useful for practical application, 〈Pinus taiwanensis, Rhododendron farrerae〉, 〈Castanopsis carlesii, Altingia chinensis〉, 〈C. carlesii, Castanopsis fargesii〉, 〈Castanopsis eyrei, C. fargesii〉, 〈P. taiwanensis, Fagus lucida〉 , 〈Machilus thunbergii, Castanopsis nigrescens〉, and （4） The results of clustering analysis based on the maximal tree method indicates that the 32 dominant species can be divided into 3 ESGs when A at o.6o, that is ESG I {Pinus massoniana, Cunning hamia lanceolata}, ESG II {P. taiwanensis, R. farrerae, Enkianthus quinqueflorus}, ESG III {C. carlesii, A. chinensis, C. eyrei, Castanopsis fabri, C. fargesii, Schima superba, Machilus thunbergii, Rhododendron latoueheae}. The results may be used for the selection of afforestation tree species in South China Forest Areas and guide the natural manag

关键词： Ecological Species Groups InterspecificAssociation Daiyun Mountain National NatureReserve Maximal Tree

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Influences of shale microstructure on mechanical properties and bedding fractures distribution

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Petroleum Science 2024年第3期21卷 1944-1954页

作者： Ming-Zhe Gu Mao sheng Shi-zhong Cheng Fan-Hao Gong Gen-sheng Li State Key Laboratory of Petroleum Resources and Engineering China University of Petroleum-BeijingBeijing2249China College of Petroleum Engineering China University of Petroleum-BeijingBeijing102249China Shenyang Center of China Geological Survey ShenyangLiaoning110034China

The difference in microstructure leads to the diversity of shale mechanical properties and bedding fractures distribution *** this paper,the microstructure and mechanical properties of Longmaxi marine shale and Qingshankou continental shale were studied by X-ray diffractometer(XRD),field emission scanning electron microscope(FE-SEM)with mineral analysis system,and ***,the typical bedding layers area was properly stratified using Focused Ion Beam(FIB),and the effects of microstructure and mechanical properties on the distribution patterns of bedding fractures were *** results show that the Longmaxi marine shale sample contains more clay mineral grains,while the Qingshankou continental shale sample contains more hard brittle mineral grains such as *** Longmaxi marine shale sample,hard brittle minerals with grain sizes larger than 20μm is18.24%and those with grain sizes smaller than 20μm is 16.22%.For Qingshankou continental shale sample,hard brittle minerals with grain sizes larger than 20μm is 40.7%and those with grain sizes smaller than 20μm is 11.82%.In comparison to the Qingshankou continental shale sample,the Longmaxi marine shale sample has a lower modulus,hardness,and *** shales are formed by alternating coarse-grained and fine-grained layers during *** average single-layer thickness of Longmaxi marine shale sample is greater than Qingshankou continental shale *** two types of shale have similar bedding fractures distribution patterns and fractures tend to occur in the transition zone from coarse-grained to fine-grained *** orientation of the fracture is usually parallel to the bedding plane and detour occurs in the presence of hard brittle *** fracture distribution density of the Longmaxi marine shale sample is lower than that of the Qingshankou continental shale sample due to the strong heterogeneity of the Qingshankou continental *** current resea

关键词： Shale Nanoindentation Microstructure Mechanical property Fracture

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Effect of Mo and cold forging deformation on strength and ductility of cobalt-based alloy L605

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Journal of Iron and Steel Research International 2024年第7期31卷 1811-1823页

作者： zhong-lin Wang Zhi-hua Gong Quan Li Han-sheng Bao School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014017Inner MongoliaChina Institute of Special Steels Central Iron and Steel Research Institute Co.Ltd.Beijing 100081China

Mo element was added to cobalt-based alloy L605,and cold forging deformation was *** effects of the addition and cold forging deformation on the microstructure and mechanical properties of the alloy were studied by thermodynamic calculation,electron backscatter diffraction,transmission electron microscopy,and X-ray *** stacking fault energy(SFE)of the alloy decreased after the addition,and the formation of stacking faults and intersections were promoted to improve the strength and *** tensile strength of the alloy with Mo increased from 1190 to 1702 MPa after 24%cold deformation,producing significant work *** strengthening mechanism is strain-induced martensitic transformation(SIMT)and deformation *** alloy,combined with Mo and after 24%deformation,had both high strength and ductility in comparison with the original cobalt-based alloy *** is attributed to the lower SFE which caused the increase in stacking fault *** the tensile process,theε-hcp phase was easily generated at the stacking fault to reduce the stress concentration and increase the *** SIMT by adjusting the density of stacking faults can improve the mechanical properties of cobalt-based ***ε-hcp phase,the interaction between deformation twins and dislocations,and the interaction between e-hcp phases during cold forging deformation caused local stress concentration,lowering ductility and toughness.

关键词： Cobalt-based alloy-Stacking fault energy Strain-induced martensitic transformation Deformation twin Cold forging deformation

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Unraveling the hydrothermal history of the Xinshuijing Na-metasomatite uranium deposit in the Longshoushan metallogenic belt， Northwest China by coupled hydrothermal zircon U–Pb and albite Ar–Ar dating

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Journal of Earth Science 2024年

作者： JUN zhong MARK MIHALASKY MICheL CUNEY sheng he JUN-JIE LI National Key Laboratory of Uranium Resource Exploration-Mining and Nuclear Remote Sensing， Beijing Research Institute of Uranium Geology International Atomic Energy Agency (IAEA)， Nuclear Fuel Cycle and Materials Section， Division of Nuclear Fuel Cycle and Waste Technology， Vienna International Center Université de Lorraine， GéoRessources CNRS State Key Laboratory of Lithospheric Evolution (SKLLE)， Institute of Geology and Geophysics， Chinese Academy of Sciences

Na-metasomatite uranium deposits are an important type of large-tonnage low-grade uranium deposit. They are characterized by an intimate association between uranium minerals and albite， and by the common development of syn-ore hydrothermal zircons. Similar to other types of uranium deposits， constraining an accurate age of mineralization remains a challenge for the Na-metasomatite type ones. In this study， we present for the first time， an approach that combines age dating results from the syn-ore albites (40Ar-39Ar) and hydrothermal zircons （U-Pb） for a typical Na-metasomatite uranium deposit， the Xinshuijing deposit in the Longshoushan metallogenic belt of northwest China. The hydrothermal zircon U-Pb and albite40Ar-39Ar ages are consistent with each other （378-366 Ma; within error）， but also identical to the previously reported uraninite chemical U-Pb ages （approximately 370 Ma）. The coupled application of hydrothermal zircon U-Pb and albite40Ar-39Ar age dating is thus regarded as a robust approach for constraining the age of mineralization for Na-metasomatite uranium deposits. An age gap of approximately 70 m.y. between uranium mineralization （～ 370 Ma） and host granitoid emplacement （about 440 Ma） suggests no direct genetic linkage between the two. Further exploration in the surrounding metamorphic units is therefore suggested， rather than only focusing on the host granitoids， especially where intensive wallrock alteration and structural features are pervasive. The varied hydrothermal zircon δ18O isotope compositions are attributed to the significant fluid-wallrock interaction during the uranium mineralization， which is consistent with our previous fluid inclusion and geochemical studies. Our study highlights the importance of selecting appropriate isotopic dating methods， which is informed by detailed paragenetic and geochemical analysis of dateable minerals formed before or coeval to the main-stage uranium mineralization. Moreover， it is underlined that the e

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Unbalanced private set intersection with linear communication complexity

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Science China(Information Sciences) 2024年第3期67卷 79-93页

作者： Quanyu ZHAO Bingbing JIANG Yuan ZHANG heng WANG Yunlong MAO sheng zhong Department of Computer Science and Technology Nanjing University Purple Mountain Lab

The private set intersection(PSI) protocol allows two parties holding a set of integers to compute the intersection of their sets without revealing any additional information to each other. The unbalanced PSI schemes consider a specific setting where a client holds a small set of the size n and a server holds a much larger set of the size m(n ■ m). The communication overhead of state-of-the-art balanced PSI schemes is O(m + n) and the unbalanced PSI schemes are O(nlogm). In this paper, we propose a novel secure unbalanced PSI protocol based on a hash proof system. The communication complexity of our protocol grows only linearly with the size of the small set. In other words, our protocol achieves communication overhead of O(n). We test the performance on a personal computer(PC) machine with a local area network(LAN)setting for the network. The experimental results demonstrate that the client only takes 2.01 s of online computation, 4.27 MB of round trip communication to intersect 1600 pieces of 32-bit integers with 220pieces of 32-bit integers with the security parameter λ = 512. Our protocol is efficient and can be applied to resource-constrained devices, such as cell phones.

关键词： unbalanced private set intersection Hash proof system linear communication complexity small set resource-constrained devices

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江西省中小学教师职后教育调查报告

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教师教育研究 2015年第5期27卷 78-83页

作者：何声钟南昌师范学院基础教育研究中心江西南昌330032

教师职后教育是教师专业发展的基本要求和途径,具有系统性、层次性和灵活性等特征。教师专业发展意识和需求与职后教育实施效果具有显著的正相关性。当前,由于应试教育局面未得到根本性扭转,教育本质异化严重,教师职后教育实施状况不尽... 详细信息

教师职后教育是教师专业发展的基本要求和途径,具有系统性、层次性和灵活性等特征。教师专业发展意识和需求与职后教育实施效果具有显著的正相关性。当前,由于应试教育局面未得到根本性扭转,教育本质异化严重,教师职后教育实施状况不尽人意,主要表现为:教师职后教育意识薄弱、功利思想严重、动力缺乏、学校顶层设计缺失、职后教育盲目性大、政府、高师院校、中小学和教师职后教育主体责任不明、制度或措施落实不力、教研组功能严重弱化、学习文化消极、氛围缺失等。对此,笔者在分析问题产生原因的基础上,提出了自己的思考。

关键词：江西中小学教师职后教育现状分析与对策

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江西省高师教育学生实践能力培养的调查与分析

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教师教育研究 2013年第2期25卷 42-47页

作者：何声钟江西教育学院基础教育研究中心江西南昌330032

教育实践能力的培养是促进师范生教师专业化的重要准备和前提,同时也是衡量学生是否具备有良好从教素质的标志。关注学生教育实践能力培养是教师职前教育发展阶段的关键。文章根据对江西省三所高师院校学生教育实践能力培养的调查和分析... 详细信息

教育实践能力的培养是促进师范生教师专业化的重要准备和前提,同时也是衡量学生是否具备有良好从教素质的标志。关注学生教育实践能力培养是教师职前教育发展阶段的关键。文章根据对江西省三所高师院校学生教育实践能力培养的调查和分析,就如何解决当前该省学生教育实践能力培养中存在的问题,提出了建议和对策。

关键词：江西高师教育学生实践能力

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Unconventional phonon spectra and obstructed edge phonon modes

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Science China(Physics,Mechanics & Astronomy) 2024年第4期67卷 114-118页

作者： Ruihan Zhang Haohao sheng Junze Deng zhong Fang Zhilong Yang Zhijun Wang Beijing National Laboratory for Condensed Matter Physics and Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China

Based on the elementary band representations(EBR),many topologically trivial materials are classified as unconventional ones(obstructed atomic limit),where the EBR decomposition for a set of electronic states is not consistent with atomic valenceelectron band *** the work,we identify that the unconventional nature can also exist in phonon spectra,where the EBR decomposition for a set of well-separated phonon modes is not consistent with atomic vibration band representations(ABR).The unconventionality has two types:typeⅠis on an empty site;and typeⅡis on an atom site with non-atomic vibration *** unconventionality is described by the nonzero real-space invariant at the *** detailed calculations show that the black phosphorus(BP)has the typeⅠunconventional phonon spectrum,while 1H-Mo Se_(2)has the typeⅡone,although their electronic structures are also ***,the obstructed phonon modes are obtained for two types of unconventional phonon spectra.

关键词： unconventional phonon spectra obstructed edge phonon mode typeⅠ&typeⅡunconventionality

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