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Geographical differences of leaf traits of the endangered plant Litsea coreana *** and its relationship with climate

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Journal of Forestry Research 2023年第1期34卷 125-135页

作者： Gangyi Yuan qiqiang guo Yaqin Zhang Qin Gui Na Xie Siqiong Luo Institute for Forest Resources and Environment of Guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceCollege of ForestryGuizhou UniversityGuiyang 550025People’s Republic of China

Seventeen morphological and anatomical characteristics of the leaves were selected from five natural populations to explore the variation in leaf traits of Lits ea core ana *** and the effects of geographical environment on these *** analysis of variance,multiple comparisons,principal component analysis(PCA),and correlation analysis were conducted to explore the variations within and between populations and their correlation with geographical and climatic *** differences in the 17 leaf traits were observed within and among *** average,the relative contribution of within population variation to total variation was 24.8%,which was lower than among population variation(54.6%).The average differentiation coefficient of the traits was 65.8%,and the average coefficient of variation 11.8%,ranging from6.7%for main vein thickness to 21.4%for petiole *** PC A results showed that morphological characteristics were divided into two categories,and the level of variation was greater than that of leaf *** of the leaf traits were significantly correlated with geography and climate and showed a gradual variation with longitude,latitude,and *** areas with high temperatures,less rainfall,and strong seasonal rainfall,the leaves are larger,longer and *** study shows that variations in leaf traits of *** *** mainly come from variations among *** level of trait differentiation among populations is high and the level of variation within populations *** findings help further understand leaf morphological characteristics of this species and can provide a valuable reference for the protection and sustainable utilization of this natural resource.

关键词： Litsea coreana var.sinensis Climate Leaf trait variations Natural populations Endangered species

Analysis of genetic diversity and prediction of Larix species distribution in the Qinghai–Tibet Plateau,China

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Journal of Forestry Research 2023年第3期34卷 705-715页

作者： qiqiang guo Huie Li Weilie Zheng Jinwen Pan Jie Lu Jiangrong Li Yu Zheng Institute for Forest Resources&Environment of Guizhou Key Laboratory of Forest Cultivation in Plateau Mountain of Guizhou ProvinceGuizhou UniversityGuiyang 550025People’s Republic of China College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China College of Agriculture Guizhou UniversityGuiyang 550025People’s Republic of China Institute of Tibet Plateau Ecology Tibet Agriculture and Animal Husbandry UniversityNyingchi Tibet 860000People’s Republic of China Key Laboratory of Forest Ecology in Tibet Plateau(Tibet Agriculture and Animal Husbandry University) Ministry of EducationNyingchi Tibet 860000People’s Republic of China Plant Research Center Chengdu Botanical GardenChengdu 610083People’s Republic of China

Larix resources in the Qinghai-Tibet Plateau have important ecological and economic ***,the lack of genetic diversity background and related research hinders the development of conservation *** this study,genetic diversity and distribution of fi ve Larix species were *** 19 polymorphic microsatellite markers to study 272 representative individuals from 13 populations,the results show low genetic diversity at the population level,with variation explained mainly by diff erentiation among *** Larix populations were classifi ed into two clades,one formed by eight populations,including three of the species in this study,***,***,and *** *** other clade consists of fi ve populations,including the other two species in this study,*** thii and *** distance of the species was aff ected by geographical isolation and genetic diversity was mainly aff ected by *** area suitable for Larix *** during the Last Glacial Maximum compared to the current distribution according to the niche model,but should increase in future climate scenarios(2050s),expanding westward along the *** results provide an important scientifi c basis for the development of conservation strategies and further the sustainable utilization of Larix resources in the Qinghai-Tibet Plateau.

关键词： Larix spp. Genetic diversity Phylogenetic relationship Genetic structure Ecological niche modeling Qinghai-Tibet Plateau

Comparison of photosynthesis and antioxidative protection in Sophora moorcroftiana and Caragana maximovicziana under water stress

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Journal of Arid Land 2014年第5期6卷 637-645页

作者： qiqiang guo WenHui ZHANG HuiE LI Ministry of Education Key Laboratory of Environment and Ecology in West China Northwest A&F University Tibet Agricultural and Animal Husbandry College National Key Station for Field Scientific Observation&Experiment

This study aims to investigate the protective roles of photosynthetic characteristics and antioxidative systems in the desiccation tolerance of Sophora moorcroftiana and Caragana maximovicziana as they adapt to arid environments. A variety of physiological and biochemical parameters in the leaves of two Leguminosae species were monitored for 1, 7, 14, 21 and 28 d of drought stress. Soil water content decreased from 38.58% to 7.33% after exposure to 28 d of water stress. The photosynthetic carbon-assimilation rates of the two Leguminosae plants decreased for non-stomatal limitation with processing water stress. The malondialdehyde content and cell membrane relative conductivity of the two species increased significantly from 1 to 21 d and then decreased. S. moorcroftiana showed higher superoxide dismutase and peroxidase activities than C. maximovicziana during the 28 d treatment period. However, the catalase activities and proline content of C. maximovicziana were higher than those of S. moorcroftiana before the water stress treatment reached 21 d. Nine physiological and biochemical parameters were selected to comprehensively evaluate the two species＇ drought-resistance by the membership function values（MFV）. The mean MFV indicated that S. moorcroftiana has a relatively stronger drought defense capability than C. maximovicziana. S. moorcroftiana mainly uses carbon-assimilation rate and osmotic adjustment to combat water deficiency.

关键词： Sophora moorcroftiana Caragana maximovicziana photosynthesis characteristic antioxidative protection drought stress

Comparative study on the chloroplast genomes of five Larix species from the Qinghai-Tibet Plateau and the screening of candidate DNA markers

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Journal of Forestry Research 2021年第5期32卷 2219-2226页

作者： qiqiang guo Huie Li Zengqiang Qian Jie Lu Weilie Zheng Institute for Forest Resources&Environment of Guizhou/College of Forestry Guizhou UniversityGuiyang 550025People’s Republic of China College of Agriculture Guizhou UniversityGuiyang 550025People’s Republic of China College of Life Sciences Shaanxi Normal UniversityXi’an 710062People’s Republic of China Key Laboratory of Forest Ecology in Tibet Plateau(Tibet Agriculture&Animal Husbandry University) Ministry of EducationNyingchi 860000TibetPeople’s Republic of China Institute of Tibet Plateau Ecology Tibet Agriculture&Animal Husbandry UniversityNyingchi 860000TibetPeople’s Republic of China

Five Larix species(***,***,***,***,and *** ***),have survived on the Qinghai-Tibet Plateau(QTP)under specific climate conditions for *** lack of genomic information seriously hinders research on the evolution,conservation and ecology of these Larix *** this study,complete chloroplast(cp)genomes of the 5 species were assembled and compared based on next generation sequencing technology combined with polymerase chain reaction *** results show that the 5 cp genomes are relatively conservative in size,gene content and arrangement,and border *** analysis showed that the species are closely related as well as to seven other species of the same *** addition,the 5 cp genomes contained few simple sequence repeats and relatively low nucleotide variability;thus,12 candidate polymorphic cp DNA markers will be helpful for further research on relevant population *** results will provide valuable genetic information for the conservation,evolution and ecology of these species and their relatives.

关键词： Larix species Plastid genome Microsatellite Phylogenetic analysis Qinghai-tibet plateau

Wear-resistant Ag-MAX phase 3D interpenetrating-phase composites:Processing,structure,and properties

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Nano Research 2024年第2期17卷 806-819页

作者： Yu guo Xi Xie Zengqian Liu Longchao Zhuo Jian Zhang Shaogang Wang qiqiang Duan Qing Jia Dake Xu Weihai Xue Deli Duan Filippo Berto Zhefeng Zhang Rui Yang Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Electrobiomaterials Institute Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education)Northeastern UniversityShenyang 110819China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Department of Chemical Engineering Materials and EnvironmentSapienza University of RomeRoma 00185Italy

Electrical contact materials are generally Ag-or Cu-based composites and play a critical role in ensuring the reliability and efficiency of electrical equipments and electronic *** MAX(M is an early transition metal,A is an element from III or IV main groups,and X is carbon or/and nitrogen)phase ceramics display a unique combination of properties and may serve as an ideal reinforcement phase for electrical contact *** biological materials evolved in nature generally exhibit three-dimensional(3D)interpenetrating-phase architectures,which may offer useful inspiration for the architectural design of electrical contact ***,a series of bi-continuous Ag-Ti_(3)SiC_(2) MAX phase composites with high ceramic contents exceeding 50 vol.%and having micron-and ultrafine-scaled 3D interpenetrating-phase architectures,wherein both constituents were continuous and mutually interspersed,were exploited by pressureless infiltration of Ag melt into partially sintered Ti_(3)SiC_(2) *** mechanical and electrical properties as well as the friction and wear performance of the composites were investigated and revealed to be closely dependent on the ceramic contents and characteristic structural *** composites exhibited a good combination of properties with high hardness over 2.3 GPa,high flexural strength exceeding 530 MPa,decent fracture toughness over 10 MPa·m^(1/2),and good wear resistance with low wear rate at an order of 10^(-5)mm^(3)/(N·m),which were much superior compared to the counterparts made by powder metallurgy *** particular,the hardness,electrical conductivity,strength,and fracture toughness of the composites demonstrated a simultaneous improvement as the structure was refined from micron-to ultrafine-scales at equivalent ceramic *** good combination of properties along with the facile processing route makes the Ag-Ti_(3)SiC_(2)3D interpenetrating-phase composites appealing for electrical contact applicatio

关键词： three-dimensional(3D)interpenetrating-phase architecture Ag-MAX(M=early transition metal A=element from III or IV main groups and X=carbon or/and nitrogen)phase composites melt infiltration electrical contact materials mechanical

Innovations in metallurgical and materials processes:advancing liquid theory and honoring ***-jie guo's contributions to physical chemistry in metallurgy

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Journal of Iron and Steel Research International 2024年第1期31卷 1-2页

作者： Shuai Liu Jing guo Han-jie guo School of Artificial Intelligence Beijing Technology and Business UniversityBeijing100048China School of Metallurgical and Ecological Engineering University of Science and Technology Beijing(USTB)Beijing100083China

Spanning three decades,***-jie guo's research group has dedicated itself to exploring the fundamental theories and practical applications of physical chemistry within the realm of *** under the assumption that molecul... 详细信息

关键词： chemistry liquid complexes

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青藏高原特有种砂生槐的核心种质构建

植物生理学报 2022年第6期58卷 1133-1144页

作者：杨兰李慧娥郭其强贵州大学农学院贵阳550025 贵州大学贵州省森林资源与环境研究中心贵阳550025

以300份砂生槐代表样本为研究对象,结合砂生槐形态特征、生物碱含量、抗旱等级与分子标记,对砂生槐资源进行核心种质构建。结果显示:用作分子标记的20对SSR引物多态百分率为89.33%,6个形态特征(冠幅、基径、分蘖数、株高、花序长、种子... 详细信息

以300份砂生槐代表样本为研究对象,结合砂生槐形态特征、生物碱含量、抗旱等级与分子标记,对砂生槐资源进行核心种质构建。结果显示:用作分子标记的20对SSR引物多态百分率为89.33%,6个形态特征(冠幅、基径、分蘖数、株高、花序长、种子数)和1种生物碱(苦参碱)含量的变异系数均在30%以上,但砂生槐资源的6个抗旱相关指标的变异系数低于10%。因此,将形态特征与生物碱含量进行10级分类,与SSR分型结果一起,采用位点优先取样策略构建核心种质,最终筛选出38份核心种质。进一步对所筛选出的核心种质相对于原始种质进行评价与确认,所构建的38份核心种质在形态特征、生物碱含量、抗旱性、地区分布及分子水平上均能够代表原始种质的遗传多样性。

关键词：砂生槐核心种质位点优先取样遗传多样性种质资源

不同马尾松林下光环境中油茶叶片和光合特征比较及其与主要环境因子的相关性

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植物资源与环境学报 2022年第6期31卷 25-33页

作者：张亚琴郭其强罗丝琼盘金文姚珊郭有燕贵州大学林学院贵州省森林资源与环境研究中心贵州贵阳550025 河西学院乡村振兴研究院甘肃张掖734000

以光下无遮挡处为对照(光照强度1719μmol·m^(-2)·s^(-1)),对马尾松(Pinus massoniana Lamb.)林缘(光照强度859μmol·m^(-2)·s^(-1))和林内(光照强度181μmol·m^(-2)·s^(-1))10年生油茶(Camellia oleifera Abel)的叶片和光合特征进行研究,对3种林下光环境中气温、空气水汽压亏缺和光合有效辐射的日变化进行比较,并对油茶叶片和光合特征指标与上述3个主要环境因子的相关性进行分析。结果表明:林缘油茶叶片的面积、周长、厚度、比叶面积、气孔密度和叶绿素含量均最高,且基本上显著(P<0.05)高于林内和对照,但气孔面积却显著低于林内和对照。在光合有效辐射为300~1800μmol·m^(-2)·s^(-1)时,林缘油茶叶片的净光合速率也明显高于林内和对照。供试3种林下光环境中,油茶叶片的最大净光合速率、表观量子效率、光饱和点和暗呼吸速率均在林缘最高、在林内最低,而光补偿点则在对照最高、在林内最低,且这5个指标在不同林下光环境间差异显著。从油菜叶片光合参数的日变化看,林内油茶叶片的净光合速率、气孔导度、蒸腾速率和水分利用效率在多数时刻最低,且3种林下光环境中这些指标的日变化趋势各异;3种林下光环境中油茶叶片胞间CO_(2)浓度和气孔限制值在不同时刻无明显规律,且其日变化趋势恰好相反。3种林下光环境中气温、空气水汽压亏缺和光合有效辐射的日变化总体上表现为先升高后降低的趋势。相关性分析结果表明:油茶叶片净光合速率、蒸腾速率和气孔限制值与3个主要环境因子均呈显著或极显著正相关,其胞间CO_(2)浓度和水分利用效率基本上与3个主要环境因子呈显著或极显著负相关,另外,比叶面积和气孔面积与光合有效辐射呈极显著正相关。综上所述,马尾松林缘油茶的叶片生长较好且光合能力较强。

关键词：油茶林下光环境叶片特征光合特征环境因子相关性分析

Emerging direct current triboelectric nanogenerator for high-entropy mechanical energy harvesting

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Science China(Technological Sciences) 2024年第5期67卷 1297-1316页

作者： CHEN Jie guo RuiLong guo HengYu College of Physics and Electronic Engineering Chongqing Normal UniversityChongqing 401331China Department of Applied Physics Chongqing UniversityChongqing 401331China

In the era of the Internet of Things(IoT),the provision of sustainable power to distributed,mobile,and low-power-consumption electronic devices is a critical *** overcome this challenge,the triboelectric nanogenerator(TENG),a highly efficient high-entropy mechanical energy harvesting device,was developed in *** device enables the direct conversion of irregular and low-frequency mechanical energy into pulsed alternating current(AC)***,the incompatibility of most electronic devices with AC signals necessitates rectifier circuits or generators that deliver direct current(DC)*** recent years,DC-TENGs have undergone extensive development,achieving significant milestones in various application fields while also facing crucial challenges that require *** this review,three categories of DC-TENG devices with distinct operating mechanisms are comprehensively explored:multiphase coupling,mechanical rectification,and air *** typical structures and working mechanisms are thoroughly discussed,and specific output performance limitations,along with corresponding optimization strategies,are ***,the applications of DC-TENGs in various scenarios are ***,the challenges faced by DC-TENGs and potential solutions are analyzed to guide further advancements in this technology.

关键词： TENG direct current working mechanisms output performance limitations optimization strategies