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Leaf functional traits and ecological strategies of common plant species in evergreen broad-leaved forests on Huangshan Mountain
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作者 Ningjie Wang Ting Lv +4 位作者 Lu Wang Shuifei Chen Lei Xie Yanming Fang Hui Ding 《Journal of Forestry Research》 2025年第1期223-243,共21页
The survival strategy of plants is to adjust their functional traits to adapt to the environment.However,these traits and survival strategies of evergreen broad-leaved forest species are not well understood.This study... The survival strategy of plants is to adjust their functional traits to adapt to the environment.However,these traits and survival strategies of evergreen broad-leaved forest species are not well understood.This study examined 10 leaf functional traits(LFTs)of 70 common plant species in an evergreen broad-leaved forest in Huangshan Mountain to decipher their adaptive strategies.The phylogenetic signals of these LFTs were assessed and phylogenetically independent contrasts(PIC)and correlation analyses were carried out.LFTs were analyzed to determine their CSR(C:competitor,S:stress-tolerator,R:ruderal)strategies.The results show that plant species exhibit different leaf functional traits and ecological strategies(nine strategies were identified;the most abundant were S/CS and S/CSR strategies).Some traits showed significant phylogenetic signals,indicating the effect of phylogeny on LFTs to an extent.Trait variations among species suggest distinct adaptation strategies to environmental changes.The study species were mainly clustered on the C-S strategy axis,with a high S component.Species leaning toward the C-strategy end(e.g.,deciduous species),favored a resource acquisition strategy characterized by higher specific leaf area(SLA),greater nutrient contents(N and P),lower leaf dry matter content(LDMC),and reduced nutrient utilization efficiency(C:N and C:P).Conversely,species closer to the S-strategy end(e.g.,evergreen species)usually adopted a resource conservative strategy with trait combinations contrary to those of C-strategy species.Overall,this study corroborated the applicability of the CSR strategy at a local scale and provides insights into the varied trait combinations and ecological strategies employed by plant species to adapt to their environment.These findings contribute to a better understanding of the mechanisms involved in biodiversity maintenance. 展开更多
关键词 leaf functional traits Phylogenetic signals Phylogenetically independent contrasts CSR ecological strategy
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Addition Formulas of Leaf Functions and Hyperbolic Leaf Functions 被引量:1
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作者 Kazunori Shinohara 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第5期441-473,共33页
Addition formulas exist in trigonometric functions.Double-angle and half-angle formulas can be derived from these formulas.Moreover,the relation equation between the trigonometric function and the hyperbolic function ... Addition formulas exist in trigonometric functions.Double-angle and half-angle formulas can be derived from these formulas.Moreover,the relation equation between the trigonometric function and the hyperbolic function can be derived using an imaginary number.The inverse hyperbolic function arsinher(r)■ro 1/√1+t^(2)dt p1tt2 dt is similar to the inverse trigonometric function arcsiner(r)■ro 1/√1+t^(2)dt p1t2 dt,such as the second degree of a polynomial and the constant term 1,except for the sign−and+.Such an analogy holds not only when the degree of the polynomial is 2,but also for higher degrees.As such,a function exists with respect to the leaf function through the imaginary number i,such that the hyperbolic function exists with respect to the trigonometric function through this imaginary number.In this study,we refer to this function as the hyperbolic leaf function.By making such a definition,the relation equation between the leaf function and the hyperbolic leaf function makes it possible to easily derive various formulas,such as addition formulas of hyperbolic leaf functions based on the addition formulas of leaf functions.Using the addition formulas,we can also derive the double-angle and half-angle formulas.We then verify the consistency of these formulas by constructing graphs and numerical data. 展开更多
关键词 leaf functions hyperbolic leaf functions lemniscate functions Jacobi elliptic functions ordinary differential equations nonlinear equations
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Differences in leaf functional traits between red and green leaves of two evergreen shrubs Photinia×fraseri and Osmanthus fragrans 被引量:13
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作者 Congyan Wang Hongguang Xiao +1 位作者 Jun Liu Jiawei Zhou 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第3期473-479,共7页
Leaf functional traits are adaptations that enable plants to live under different environmental conditions. This study aims to evaluate the differences in leaf functional traits between red and green leaves of two eve... Leaf functional traits are adaptations that enable plants to live under different environmental conditions. This study aims to evaluate the differences in leaf functional traits between red and green leaves of two evergreen shrubs Photinia × fraseri and Osrnanthus fragrans. Specific areas of red leaves are higher than that of green leaves in both species. Thus, the material investment per unit area and per lamina of red leaves is significantly lower than that of green leaves, implying an utmost effort of red leaves to increase light capture and use efficiency because of their low leafchlorophyll concentration. The higher petiole length of green leaves compared with that of red leaves indicates that adult green leaves may have large fractional biomass allocation to support the lamina structures in capturing light with maximum efficiency and obtaining a high growth rate. The high range of the phenotypic plasticity of leaf size, leaf thickness, single-leaf wet and dry weights, and leaf moisture of green leaves may be beneficial in achieving efficient control of water loss and nutrient deprivation. The high range of phenotypic plasticity of leaf chlorophyll concentration of red leaves may be advantageous in increasing resource (especially light) capture anduse efficiency because this leaf type is juvenile in the growth stage and has low leaf-chlorophyll concentration. 展开更多
关键词 Foliage color leaf functional traits Osmanthus fragrans Photinia × fraseri Red robin Specific leaf area
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Variations in leaf functional traits and physiological characteristics of Abies georgei var.smithii along the altitude gradient in the Southeastern Tibetan Plateau 被引量:2
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作者 GUO Qi-qiang LI Hui-e ZHANG Wen-hui 《Journal of Mountain Science》 SCIE CSCD 2016年第10期1818-1828,共11页
Variations in leaf functional traits of Abies georgei var. smithii at 3700, 3900, 4100, 4300, and 4390 m altitude were investigated in 15 typical plots in the Southeastern Tibetan Plateau. In each plot, three seedling... Variations in leaf functional traits of Abies georgei var. smithii at 3700, 3900, 4100, 4300, and 4390 m altitude were investigated in 15 typical plots in the Southeastern Tibetan Plateau. In each plot, three seedlings were selected, of which functional leaves in current-year sunny branches were chosen for the measurement of morphological, photosynthetic, and physiological and biochemical characteristics, and their variations were analyzed. Results showed that significant variations existed among the leaf functional traits of A. georgei var. smithii along the altitudinal gradient, as well as their physiological adaption indicators. Leaf area decreased, while the mass per area and thickness of leaf increased at an altitude above 4,100 m. The maxima of pigment, total nitrogen concentration, net photosynthesis rate during light-saturated, and when water use efficiency appeared at 4100 m altitude. In addition, A. georgei var. smithii seedlings regulated the activities of superoxide dismutase and ascorbate peroxidase to resist abiotic stress under 4100 m altitude. Meanwhile, malondialdehyde concentration and the dark respiration rate rapidly increased, which indicates that A. georgei var. smithii seedlingssuffered from heavy abiotic stress from 4100 m to 4390 m altitude. Basing on variations in leaf functional traits along the altitude gradient, we inferred that 4100 m altitude was the suitable region for A. georgei var. smithii growth in the Sygera Mountain. Moreover, the harsh environment was the main limiting factor for A. georgei var. smithii population expansion to high altitude. 展开更多
关键词 Alpine plant Abies georgei leaf functional traits Photosynthetic parameters Enzyme activity and malondialdehyde concentration
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Lemniscate of Leaf Function
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作者 Kazunori Shinohara 《Computer Modeling in Engineering & Sciences》 SCIE EI 2021年第1期275-292,共18页
A lemniscate is a curve defined by two foci,F_(1) and F_(2).If the distance between the focal points of F_(1)−F_(2) is 2a(a:constant),then any point P on the lemniscate curve satisfy the equation PF_(1)·PF_(2)=a^... A lemniscate is a curve defined by two foci,F_(1) and F_(2).If the distance between the focal points of F_(1)−F_(2) is 2a(a:constant),then any point P on the lemniscate curve satisfy the equation PF_(1)·PF_(2)=a^(2).Jacob Bernoulli first described the lemniscate in 1694.The Fagnano discovered the double angle formula of the lemniscate(1718).The Euler extended the Fagnano’s formula to a more general addition theorem(1751).The lemniscate function was subsequently proposed by Gauss around the year 1800.These insights were summarized by Jacobi as the theory of elliptic functions.A leaf function is an extended lemniscate function.Some formulas of leaf functions have been presented in previous papers;these included the addition theorem of this function and its application to nonlinear equations.In this paper,the geometrical properties of leaf functions at n=2 and the geometric relation between the angle θ and lemniscate arc length l are presented using the lemniscate curve.The relationship between the leaf functions sleaf_(2)(l)and cleaf_(2)(l)is derived using the geometrical properties of the lemniscate,similarity of triangles,and the Pythagorean theorem.In the literature,the relation equation for sleaf_(2)(l)and cleaf_(2)(l)(or the lemniscate functions,sl(l)and cl(l))has been derived analytically;however,it is not derived geometrically. 展开更多
关键词 GEOMETRY lemniscate of Bernoulli leaf functions lemniscate functions Pythagorean theorem triangle similarity
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Differences in leaf functional traits between exotic and native Compositae plant species 被引量:5
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作者 WANG Cong-yan LIU Jun +1 位作者 ZHOU Jia-wei XIAO Hong-guang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第10期2468-2474,共7页
This study aims to determine the differences in leaf functional traits and phenotypic plasticity of leaf functional traits between exotic and native Compositae plant species. Leaf width of exotic plants was significan... This study aims to determine the differences in leaf functional traits and phenotypic plasticity of leaf functional traits between exotic and native Compositae plant species. Leaf width of exotic plants was significantly lower than that of native species. Leaf length, specific leaf area(SLA), single-leaf wet and dry weights, leaf moisture, and leaf thickness of exotic plants were also lower than those of native species but not significantly. The leaf shape index of exotic plants was higher than that of native species but not significantly. This implies that the relatively low leaf construction cost for exotic plants may play an important role in the success of their invasions. The higher leaf shape index and lower leaf width of exotic plants can enhance the efficiency of resource capture(especially sunlight capture) via adjustments to leaf shape and size, thereby increasing the survival of exotic plants. The plasticity indices of single-leaf wet weight and leaf thickness of exotic plants were significantly lower than those of native species. The lower phenotypic plasticity of single-leaf wet weight and leaf thickness of exotic plants may be the result of a cost to plasticity. That is, if the plasticity is too high, the fitness of plant species might be reduced sharply under unfavorable environments. Thus, lower plasticity of leaf functional traits may compensate for the negative impact of adverse environments and stabilize leaf construction costs for exotic plants. Moreover, reduced phenotypic plasticity might be one of the key competitive strategies by which exotic plants successfully invade new habitats. Overall, exotic plants did not always exhibit higher values of leaf functional traits or increased phenotypic plasticity of leaf functional traits compared with native species. 展开更多
关键词 leaf functional TRAITS specific leaf area (SLA) PHENOTYPIC plasticity EXOTIC plants COMPOSITAE
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Latitudinal pattern and the driving factors of leaf functional traits in 185 shrub species across eastern China 被引量:12
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作者 Yongkai Luo Huifeng Hu +3 位作者 Mengying Zhao He Li Shangshi Liu Jingyun Fang 《Journal of Plant Ecology》 SCIE CSCD 2019年第1期67-77,共11页
Aims To explore the pattern of the leaf functional traits of shrub species along a latitudinal gradient in eastern China and determine the driv-ing factors of leaf trait variation at a large scale.Methods We investiga... Aims To explore the pattern of the leaf functional traits of shrub species along a latitudinal gradient in eastern China and determine the driv-ing factors of leaf trait variation at a large scale.Methods We investigated the leaf thickness(LT),leaf area(LA),specific leaf area(SLA)and leaf dry mass content(LDMC)of 185 shrub species from 13 sites across eastern China.The trends of these four-leaf traits were ana-lyzed with respect to latitude,and the differences between different life forms(e.g.,evergreen and deciduous)and habitats(e.g.,understory and typical)were compared.We quantified the effects of the plant life forms and environmental factors on the leaf traits via mixed-model analyses.Important Findings The LT and LA decreased,whilst and the LDMC increased,as the latitude increased,and significant differences in these traits were observed between the different plant life forms.The LT and LA were smaller,whereas the SLA and LDMC were larger in decidu-ous shrubs than in evergreen shrubs.Among the different habitats,the LA and SLA were larger,while the LDMC was smaller in under-story shrubs than in typical shrub species.These results indicate that typical shrub species are better adapted to drier environments,as indicated by a reduced LT and increased LDMC.Furthermore,general linear models showed that variations in the four-leaf traits with respect to latitude were mainly caused by a shift in plant life forms. 展开更多
关键词 shrub species leaf functional traits latitude trend different life forms eastern China
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矿区6种藤本植物的叶功能性状及其对覆土厚度的响应
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作者 刘仁 袁小东 +6 位作者 孙韵 蔡宗明 何平 宋云霞 喻龙华 张华聪 厉月桥 《西南大学学报(自然科学版)》 北大核心 2026年第1期99-114,共16页
明确6种藤本植物在不同覆土厚度下的适应性差异,筛选出耐薄土或厚土的优势物种,为矿区人工植被重建提供科学选种和覆土厚度依据,提升生态修复效率。以矿区中6种藤本植物(五叶地锦、葛藤、常春藤、凌霄、常春油麻藤、爬山虎)为试验材料,... 明确6种藤本植物在不同覆土厚度下的适应性差异,筛选出耐薄土或厚土的优势物种,为矿区人工植被重建提供科学选种和覆土厚度依据,提升生态修复效率。以矿区中6种藤本植物(五叶地锦、葛藤、常春藤、凌霄、常春油麻藤、爬山虎)为试验材料,利用主成分分析法、隶属函数法研究3种覆土厚度下6种藤本植物叶功能性状及氮磷养分策略的差异,对6种藤本植物各项指标进行综合分析及评价。结果表明:①在覆土厚度20 cm下五叶地锦生长状况最佳;在覆土厚度40 cm下爬山虎和凌霄生长优势较高;在覆土厚度60 cm下葛藤、常春藤和常春油麻藤表现出较好的适应性和生长优势。②五叶地锦和凌霄在覆土厚度20 cm下增加根系投资以增强养分获取,在覆土厚度60 cm下则转向增加叶生物量以优化光合作用;葛藤和常春油麻藤在各厚度下均表现出较高的生物量积累,显示出较强的适应潜力;在覆土厚度20 cm下葛藤和常春油麻藤表现为“快投资-回报”资源获取型策略,具有高比叶面积、低叶干物质含量特征,利于快速生长与资源捕获,而爬山虎和常春藤则倾向于“慢投资-回报”资源保守型策略,具有高比叶质量和叶干物质含量,增强了其对贫瘠环境的耐受性。③所有藤本植物生长均受氮磷限制,不同藤本植物在不同覆土厚度下对氮磷养分的吸收与分配策略存在差异。五叶地锦在薄土层(20 cm)下茎根氮磷吸收量突出;葛藤与常春油麻藤则在厚土层(60 cm)下各器官养分吸收量较高,体现了豆科植物的固氮优势。总的来看,藤本植物通过调整生物量分配、叶片形态和养分吸收策略来适应不同覆土厚度以提升生长和竞争力。 展开更多
关键词 藤本植物 叶功能性状 叶经济谱 覆土厚度
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Genetic differentiation in functional traits among wild cherry (Prunus avium L.) half-sib lines 被引量:1
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作者 Srđan Stojnić Branislav Kovačević +4 位作者 Marko Kebert Verica Vasić Vanja Vuksanović Branislav Trudić Saša Orlović 《Journal of Forestry Research》 SCIE CAS CSCD 2022年第3期991-1003,共13页
Understanding intra-specific variation in leaf functional traits is one of the key requirements for the evaluation of species adaptive capacity to ongoing climate change, as well as for designing long-term breeding an... Understanding intra-specific variation in leaf functional traits is one of the key requirements for the evaluation of species adaptive capacity to ongoing climate change, as well as for designing long-term breeding and conservation strategies. Hence, data of 19 functional traits describing plant physiology, antioxidant properties, anatomy and morphology were determined on 1-year-old seedlings of wild cherry (Prunus avium L.) half-sib lines. The variability within and among half-sib lines, as well as the estimation of multi-trait association, were examined using analysis of variance (ANOVA) followed by Tukey's honestly significant difference test and multivariate analyses: principal component analysis (PCA), canonical discriminant analysis (CDA) and stepwise discriminant analysis (SDA). Pearson’s correlation coefficient was used to evaluate linear correlation between the study parameters. The results of the ANOVA showed the presence of statistically significant differences (P < 0.01) among half-sib lines for all study traits. The differences within half-sib lines, observed through the contribution of the examined sources of variation to the total variance (%), had higher impact on total variation in the majority of the examined traits. Pearson’s correlation analysis and PCA showed strong relationships between gas exchange in plants and leaf size and stomatal density, as well as between leaf biomass accumulation, intercellular CO_(2) concentration and parameters related to antioxidant capacity of plants. Likewise, the results of SDA indicate that transpiration and stomatal conductance contributed to the largest extent, to the discrimination of the wild cherry half-sib lines. In addition, PCA and CDA showed separation of the wild cherry half-sib lines along the first principal component and first canonical variable with regards to humidity of their original sites. Multiple adaptive differences between the wild cherry half-sib lines indicate high potential of the species to adapt rapidly to climate change. The existence of substantial genetic variability among the wild cherry half-sib lines highlights their potential as genetic resources for reforestation purposes and breeding programmes. 展开更多
关键词 Wild cherry Common garden experiment VARIABILITY Multivariate statistics leaf functional traits
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基于叶经济谱特征的宿迁园林植物景观提升策略研究
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作者 罗东志 毛安元 +1 位作者 姜璐 高飞 《国土与自然资源研究》 2026年第1期88-93,共6页
随着城市化进程的加快,城市生态环境问题日益凸显,城市绿地作为城市生态系统的重要组成部分,其生态服务功能愈发重要。园林植物作为城市绿地的核心要素,它的叶功能性状可以直接反映出植物对环境的适应策略。本文以宿迁市7座城市公园的5... 随着城市化进程的加快,城市生态环境问题日益凸显,城市绿地作为城市生态系统的重要组成部分,其生态服务功能愈发重要。园林植物作为城市绿地的核心要素,它的叶功能性状可以直接反映出植物对环境的适应策略。本文以宿迁市7座城市公园的51种常见园林植物为研究对象,通过测定15项叶功能性状指标,运用单因素方差分析(one-way ANOVA)、主成分分析(PCA)及模糊隶属函数等方法,分析区域内的园林植物叶经济谱特征及现存的景观问题,并结合叶功能性状与环境适配性原理,提出具有针对性的景观提升策略,并以古黄河水景公园为例进行实证验证。研究表明,宿迁园林植物叶功能性状存在显著种间及生长型差异,且性状间呈现稳定协变关系,基于此构建的植物遴选与配置体系可以有效的提升景观生态质量。本研究为宿迁及长三角北翼等同类城市的园林植物景观优化提供了科学支撑。 展开更多
关键词 风景园林 宿迁市 园林植物 叶功能性状 植物景观优化策略
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Leaf N and P stoichiometry of 57 plant species in the Karamori Mountain Ungulate Nature Reserve,Xinjiang,China 被引量:18
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作者 TAO Ye WU Ganlin +1 位作者 ZHANG Yuanming ZHOU Xiaobing 《Journal of Arid Land》 SCIE CSCD 2016年第6期935-947,共13页
Nitrogen (N) and phosphorus (P) are the major nutrients that constrain plant growth and development, as well as the structure and function of ecosystems. Hence, leaf N and P patterns can contribute to a deep under... Nitrogen (N) and phosphorus (P) are the major nutrients that constrain plant growth and development, as well as the structure and function of ecosystems. Hence, leaf N and P patterns can contribute to a deep understanding of plant nutrient status, nutrient limitation type of ecosystems, plant life-history strategy and differentiation of functional groups. However, the status and pattern of leaf N and P stoichiometry in N-deficiency desert ecosystems remain unclear. Under this context, the leaf samples from 57 plant species in the Karamori Mountain Ungulate Nature Reserve, eastern Junggar Desert, China were investigated and the patterns and interrelations of leaf N and P were comparatively analyzed. The results showed that the average leaf N concentration, P concentration, and N:P ratio were 30.81 mg/g, 1.77 mg/g and 17.72, respectively. This study found that the leaf N concentration and N:P ratio were significantly higher than those of studies conducted at global, national and regional scales; however, the leaf P concentration was at moderate level. Leaf N concentration was allometrically correlated with leaf P and N:P ratio across all species. Leaf N, P concentrations and N:P ratio differed to a certain extent among plant functional groups. C4 plants and shrubs, particularly shrubs with assimilative branches, showed an obviously lower P concentration than those of C3 plants, herbs and shrubs without assimilative branches. Shrubs with assimilative branches also had lower N concentration. Fabaceae plants had the highest leaf N, P concentrations (as well as Asteraceae) and N:P ratio; other families had a similar N, P-stoichiometry. The soil in this study was characterized by a lack of N (total N:P ratio was 0.605), but had high N availability compared with P (i.e. the available N:P ratio was 1.86). This might explain why plant leaves had high N concentration (leaf N:P ratio〉16). In conclusion, the desert plants in the extreme environment in this study have formed their intrinsic and special stoichiometric characteristics in relation to their life-history strategy. 展开更多
关键词 leaf stoichiometry desert plant functional group nutrient limitation Junggar Desert Karamori Mountain
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Relationship Between Allelopathic Effects and Functional Traits of Different Allelopathic Potential Rice Accessions at Different Growth Stages 被引量:1
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作者 XU Gaofeng SHEN Shicai +3 位作者 ZHANG Fudou ZHANG Yun Kato-Noguchi HISASHI Roy Clements DAVID 《Rice science》 SCIE CSCD 2018年第1期32-41,共10页
In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions... In this study,effects of temperature,light and their interactions on allelopathic effects and the functional traits specific leaf area(SLA)and stem mass fraction(SMF)of different allelopathic potential rice accessions at different growth stages were analyzed.The main results were as follows:Allelopathic responses to temperature and light varied with different allelopathic potential rice accessions at different growth stages.With the rise of temperature and the extension of photoperiod,allelopathic effect increased firstly and then decreased at 2–3 leaf stage,but increased constantly at the 4–5 and 7–8 leaf stages in strong allelopathic rice accessions[O.longistaminata,F1(O.longistaminata×RD23),F2(RL159 and RL169)].Temperature had significant impact on allelopathic effect without considering light factors,but light showed little effect on rice allelopathy at the same temperature conditions.The greatest allelopathic effect was attained with moderate temperature and long photoperiod at 2–3 leaf stage in strong allelopathic rice accessions,but all the rice accessions showed weak allelopathic effects at the low temperature condition(15oC/10oC),and the influence of different factors on allelopathy followed a general trend as temperature>leaf stage>light,indicating that among the multiple factors impacting rice allelopathy,temperature was the main factor.Allelopathic characteristics of F1 and F2 to various temperature and light were similar to O.longistaminata,showing that allelopathic genes from wild rice can be expressed in its descendants.Temperature and light also had significant effects on SLA and SMF,and rice allelopathy was closely correlative to SLA in strong allelopathic rice accessions at the 4–5 and 7–8 leaf stages,but there was no correlation between rice allelopathy and SMF at different growth stages.These results suggested that rice adjust the relationship between allelopathy and SLA and adapt to the varied environments,and that high temperature and long photoperiod can enhance rice allelopathic activity. 展开更多
关键词 RICE ALLELOPATHY environment change functional TRAIT specific leaf area stem mass FRACTION temperature-light interaction
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沙冬青叶绿素荧光及叶功能性状对脱水胁迫的响应及生态适应性研究
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作者 王方琳 柴成武 +2 位作者 贺访印 胡小柯 王理德 《干旱区资源与环境》 北大核心 2025年第7期84-91,共8页
为探究民勤沙生植物园中蒙古沙冬青和新疆沙冬青的生态适应性,文中测定了离体脱水胁迫下两种沙冬青的叶绿素荧光参数,并对叶片功能性状特征进行了分析。结果表明:两种沙冬青叶绿素荧光参数均随脱水时间的延长而降低,蒙古沙冬青叶绿素荧... 为探究民勤沙生植物园中蒙古沙冬青和新疆沙冬青的生态适应性,文中测定了离体脱水胁迫下两种沙冬青的叶绿素荧光参数,并对叶片功能性状特征进行了分析。结果表明:两种沙冬青叶绿素荧光参数均随脱水时间的延长而降低,蒙古沙冬青叶绿素荧光参数值均高于新疆沙冬青,说明蒙古沙冬青叶片具有较强的光合作用能力。蒙古沙冬青叶片厚度、叶干物质含量、比叶面积等功能性状指标均优于新疆沙冬青,相对水分亏缺低于新疆沙冬青,说明在同样的生境条件下,蒙古沙冬青对水分和养分的吸收效率较高,而当生境条件缺水时,叶片又表现出较强的保水性能,并能将养分储存到器官中。综合上述分析,蒙古沙冬青对民勤当地环境条件具有较强的适应性,而新疆沙冬青虽然也能在引种地生长,但适应性不如蒙古沙冬青。为了更好地适应民勤恶劣的气候条件,蒙古沙冬青主要通过增加叶片厚度、提高叶片干物质含量、提高叶片储水性等策略,延长叶片寿命,从而获得较强的竞争优势,增强对干旱、盐碱等自然条件的适应能力。 展开更多
关键词 新疆沙冬青 蒙古沙冬青 脱水胁迫 叶功能性状 叶绿素荧光
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A NEW QUANTITATIVE WAY FOR DETERMINING LEAF AREA INDEX AND NET PRIMARY PRODUCTIVITY IN REGIONAL SCALE 被引量:7
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作者 Zhang Renhua(Institute of Geography, CAS, Bejing 100101, P.R. China)Andres Kuusk(Estorua Observatory, Tatu, Estorua)Chen Gang(Ground Station of Satellite Remote Sensing, CAS, Behing 100086, P.R. China)Alan Strahler Li Xiaonen(Remote Sensing Cater, Boston 《Journal of Geographical Sciences》 SCIE CSCD 1996年第4期1-17,共17页
An inversion of bidirectional reflection distribution fiJnedon (BRDF) wastested using NK Model and NOAA AVHRR datu. The test involVed sensitiveanalysis, optimum inversion selecting, ground simulated expenment, calibra... An inversion of bidirectional reflection distribution fiJnedon (BRDF) wastested using NK Model and NOAA AVHRR datu. The test involVed sensitiveanalysis, optimum inversion selecting, ground simulated expenment, calibrahngmeasuremed with satellite and computer image processmg. Results of comparisonwith NDVI indicatal that inversion of BRDF will have brigh developing prospect inthe next decade. 展开更多
关键词 leaf area index transmission coefficient inversion sensitivity bidirectional refectance distribution function
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激活函数LeafSpring的构建及多数据集对比研究 被引量:3
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作者 郜天柱 《信息与控制》 CSCD 北大核心 2020年第3期306-314,322,共10页
针对神经网络中ReLU激活函数存在返回值非负及神经元未激活等问题,提出了一种全新的类ReLU激活函数——LeafSpring. LeafSpring既继承了ReLU的优势,又可以返回负值,通用性更强. LeafSpring函数的推导及函数性质也会被讨论.该激活函数还... 针对神经网络中ReLU激活函数存在返回值非负及神经元未激活等问题,提出了一种全新的类ReLU激活函数——LeafSpring. LeafSpring既继承了ReLU的优势,又可以返回负值,通用性更强. LeafSpring函数的推导及函数性质也会被讨论.该激活函数还引入了刚度系数k,可以通过训练主动调节相邻两层的权重系数.为了减少计算量, LeafSpring可以在一定情况下简化为ReLU或Softplus.为了展现LeafSpring激活函数的性能,还将其与ReLU、 Softplus及Sigmoid在4种不同类型的数据集上进行拟合精度对比.对比结果表明, LeafSpring在不同的数据集上均能兼顾拟合精度和收敛速度且在小网格规模可以更快、更准确地拟合复杂非线性函数. 展开更多
关键词 激活函数 神经网络 线性整流函数(ReLU) leafSpring
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调控大白菜花青素合成基因的研究进展
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作者 张德双 辛晓云 +8 位作者 李玉各 张凤兰 于拴仓 苏同兵 汪维红 李佩荣 余阳俊 赵岫云 卢桂香 《中国蔬菜》 北大核心 2025年第9期33-41,共9页
紫色大白菜球色艳丽,富含花青素。由于花青素具有抗氧化、防癌、增强人体免疫力等保健功能,所以紫色大白菜及其花青素功能基因的研究与应用一直是国内外的热点话题。本文基于近20年来国内外有关大白菜紫色性状基因的来源途径及其叶球的... 紫色大白菜球色艳丽,富含花青素。由于花青素具有抗氧化、防癌、增强人体免疫力等保健功能,所以紫色大白菜及其花青素功能基因的研究与应用一直是国内外的热点话题。本文基于近20年来国内外有关大白菜紫色性状基因的来源途径及其叶球的紫色性状表现、控制不同紫色性状的花青素合成途径基因及其应用等文献报道,综述了大白菜花青素合成途径的转录因子和结构基因,旨在梳理调控紫色大白菜花青素生物合成的分子机制,总结大白菜花青素合成的关键功能基因等突破性成果,以期进一步阐释不同紫色性状基因导致大白菜呈现不同紫色表型与紫色叶球剖面的原因,并辅助于紫色大白菜新品种选育。 展开更多
关键词 紫色大白菜 叶球 花青素功能基因 调控网络 综述
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静脉应用银杏叶制剂治疗急性缺血性卒中有效性和安全性的meta分析
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作者 胡燕琴 赵陶丽 +2 位作者 李申 郭东兴 赵志刚 《中国卒中杂志》 北大核心 2025年第4期462-469,共8页
目的系统评价静脉应用银杏叶制剂治疗急性缺血性卒中(acute ischemic stroke,AIS)的有效性和安全性。方法计算机检索PubMed、Embase、Cochrane Library等英文数据库,以及万方、中国知网、维普等中文数据库,分析银杏叶制剂静脉注射治疗AI... 目的系统评价静脉应用银杏叶制剂治疗急性缺血性卒中(acute ischemic stroke,AIS)的有效性和安全性。方法计算机检索PubMed、Embase、Cochrane Library等英文数据库,以及万方、中国知网、维普等中文数据库,分析银杏叶制剂静脉注射治疗AIS的随机对照试验,检索时限为建库至2024年7月30日。使用Cochrane RevMan偏倚风险评估表评价纳入研究的质量。使用RevMan 5.3软件,对银杏叶制剂治疗AIS的预后、早期神经功能改善、神经功能缺损、总有效率、不良反应等指标进行meta分析。结果本研究共纳入9篇文献,其中英文文献3篇,中文文献6篇,共6111例患者,其中对照组3103例,试验组3008例。meta分析结果显示,静脉应用银杏叶制剂可提高AIS患者的预后良好(mRS评分≤2分)率(OR 1.95,95%CI 1.72~2.22,P<0.001),降低mRS评分[标准化均数差(standardized m ean difference,SMD)-0.67,95%CI-0.76~-0.58,P<0.001],提高患者的早期神经功能改善率(OR 1.23,95%CI 1.07~1.41,P=0.003),降低患者的NIHSS评分(SMD-1.36,95%CI-1.54~-1.17,P<0.001)。另外,静脉应用银杏叶制剂可以提高AIS治疗的总有效率(OR 3.68,95%CI 1.81~7.49,P<0.001),且不增加不良反应的发生率(OR 1.01,95%CI 0.85~1.20,P=0.870)。结论静脉应用银杏叶制剂对AIS具有脑细胞保护作用,可改善患者的预后,且不增加不良反应。 展开更多
关键词 急性缺血性卒中 银杏叶提取物 神经功能 预后 不良反应
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河西走廊荒漠植物优势种叶片功能性状变异及权衡
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作者 李善家 李来周 +2 位作者 缪潆祥 苟伟 苏培玺 《干旱区研究》 北大核心 2025年第3期480-488,共9页
河西走廊不同生活型植物叶片功能性状的变异特征及其权衡关系对保持该地区生态系统稳定具有重要意义。为了解不同生活型植物对干旱环境的适应机制及其生态适应策略,沿河西走廊由东南向西北自然降水递减梯度设置东段、中段、西段调查样地... 河西走廊不同生活型植物叶片功能性状的变异特征及其权衡关系对保持该地区生态系统稳定具有重要意义。为了解不同生活型植物对干旱环境的适应机制及其生态适应策略,沿河西走廊由东南向西北自然降水递减梯度设置东段、中段、西段调查样地,选取26种优势荒漠植物,其中灌木14种,草本12种,分析了14项叶片关键功能性状的变异特征和区域格局,探讨了叶片功能性状间的权衡关系与适应策略。结果表明:(1)河西走廊荒漠植物优势种叶片束缚水含量(BW)、碳磷比(C:P)、植株高度(H)、叶片自由水含量(FW)变异系数超过100%。(2)河西走廊东、中、西段不同区域植物表现出多样化的生存策略,东段灌木、草本植物在叶经济谱(LES)中的位置更靠近“缓慢投资-收益”型物种一端,中段灌木位于LES“缓慢投资-收益”型物种一端,草本则更靠近“快速投资-收益”型物种一端,西段灌木在资源丰富条件下采取“快速投资-收益”型策略,草本植物则在不利的土壤条件下采取“缓慢投资-收益”型策略。综上所述,植物生存策略受多种生态因素影响,通过性状间的优化组合与资源权衡分配实现对干旱环境的适应。 展开更多
关键词 荒漠植物 功能性状 叶经济谱 河西走廊
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叶形与叶色在园林景观设计中的应用 被引量:3
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作者 赵莹 《分子植物育种》 北大核心 2025年第2期622-627,共6页
叶形与叶色在园林景观设计中起着至关重要的作用,能显著提升景观的视觉效果和生态价值。本研究系统性地分析和总结不同叶形与叶色在园林景观设计中的应用效果和实际案例,为未来的设计实践提供理论支持和参考依据。通过国内外相关研究成... 叶形与叶色在园林景观设计中起着至关重要的作用,能显著提升景观的视觉效果和生态价值。本研究系统性地分析和总结不同叶形与叶色在园林景观设计中的应用效果和实际案例,为未来的设计实践提供理论支持和参考依据。通过国内外相关研究成果和优秀设计案例的整理和分析,本研究归纳出不同叶形与叶色在园林景观设计中的应用特点和规律。研究发现,不同的叶形如针状、心形、掌状等,以及多样的叶色如绿色、红色、紫色等,在不同类型的景观设计中都能产生独特的视觉效果和空间感受。此外,叶形与叶色的搭配使用还能够强化景观的层次感和深度,增强环境的美观性和生态功能。未来的园林景观设计应更加注重多样性的体现,通过创新设计手法和科学管理,提升城市绿地的整体品质和人居环境的舒适度。本研究为叶形与叶色在园林景观设计中的应用提供了系统的理论支持和实践指导,对未来景观设计的创新和优化具有重要参考价值。 展开更多
关键词 叶形 叶色 园林景观设计 视觉效果 生态功能
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Comparing the compositions and influence of aerosol particles retained on trees,shrubs,and herbs
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作者 Fangmin Fei Siqi Chen +2 位作者 Yaobin Song Ming Dong Hua Yu 《Journal of Environmental Sciences》 2025年第11期645-661,共17页
Aerosol particle pollution has become an increasing serious environmental problem,and urban vegetation plays a long-lasting and positive role in mitigating it.This study compared the particle capture abilities of tree... Aerosol particle pollution has become an increasing serious environmental problem,and urban vegetation plays a long-lasting and positive role in mitigating it.This study compared the particle capture abilities of trees,shrubs,and herbs,and examined the compositions and influence of aerosol particles accumulated on leaf functional traits.Retained particles primarily contained Ca^(2+),K^(+),SO_(4)^(2-),NO_(3)^(-)and NH_(4)^(+),indicating their anthropogenic origins.The leathery-leaved tree Osmanthus fragrans and the papery-leaved herb Alternanthera sessilis demonstrated the higher competence in particle accumulation than other plants,and leaf morphologic structures(e.g.,leaf grooves,trichomes,waxy layers,and stomata characteristics)were closely associated with particle capture by plant species.Particle retention negatively impacted stomata,impeding photosynthesis,and reducing transpiration.In response to particle accumulation,plants tended to decrease specific leaf area and adjust stomatal conductance.Both growth form and leaf texture significantly influenced the particle capture abilities of different plant species.The substantial contribution of plants,particularly herbs in the lower vegetation strata,to particle removal should not be overlooked.Vegetation with a tree-shrub-herb configuration excels at particle capture,offering potential advantages in mitigating particle pollution and enhancing ecological benefits. 展开更多
关键词 Aerosol particles leaf texture leaf functional traits Particle capture Plant growth form
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