Analysis of relationships among leaf functional traits and economics spectrum of plant species in the desert steppe of Nei Mongol

Aims Grassland desertification is being accelerated because of adverse climate change effects and unsustainable land uses, resulting in several major environmental problems. However, there are few studies on the economics spectrum of different plant functional types in desert steppe. The objectives of the current study are to examine the relationships among leaf functional traits of native plant species, to compare the functional traits among different plant functional types, and to determine whether an economic spectrum exists for the majority of species in the desert steppe of Damao Banner, Nei Mongol, China.
Methods Photosynthetic and chlorophyll fluorescence parameters, specific leaf area (SLA), and leaf nitrogen contents across 24 species of different functional types were measured in situ in the desert steppe ecosystem. Non-parametric tests were used to analyze leaf trait differences in plant species of different functional types. Linear regression analysis was used to determine the relationships among leaf traits in different plant species. Finally, a comprehensive analysis on these leaf traits in different plant species was conducted using the principal component analysis. All data analyses were performed using SPSS 16.0 (SPSS, Chicago, USA).
Important findings Significant differences among plant functional types were found in most of the leaf traits. SLA and mass-based nitrogen concentration (N_mass) in grasses were 2.39 and 1.20 folds, respectively, of that in shrubs; area-based photosynthetic capacity (A_area), SLA, and photosynthetic nitrogen use efficiency (PNUE) in annual species were 1.93, 2.13, and 4.24 folds, respectively, of that in perennial species; and A_area, SLA, and PNUE in C₄ species were 2.25, 1.73, and 3.61 folds, respectively, of that in C₃ species. Almost all relationships significantly differed (p < 0.01) among the leaf traits, with exception of the relationships between A_area and area-based nitrogen concentration (N_area) and between quantum yield of PSII electron transport (Φ_PSII) and SLA, implying that an economic spectrum may exist in the desert steppe ecosystem. The relationships of N_area, mass-based photosynthetic capacity (A_mass), and PNUE with SLA were most significantly strong (R² = 0.54, 0.62, 0.60, respectively; p < 0.01). Results in this study suggest that the annuals, grasses, and C₄ species might be located at the end of the leaf economic spectrum with high area-based photosynthetic rate, high nitrogen concentration on mass basis, short leaf lifespan, and high SLA; whereas the perennials, shrubs, and C₃ species could be located at the another end of the economic spectrum with contrasting traits.     

翅果油树及其群落中7种优势木本种类的叶性特征比较

Taking Elaeagnus mollis Diels and seven dominant woody species in its community from Yicheng County of Shanxi Province as research objects, leaf traits including specific leaf area (SLA), nitrogen content in leaf per unit area ( Narea ) , leaf dry matter content ( LDMC ) and photosynthetic nitrogen use efficiency ( PNUE ) were compared, and correlations of SLA value with LDMC and PNUE values were analyzed. The results show that there are different degree variations in four indexes of leaf traits of E. mollis, Vitex negundo var. heterophylla ( Franch.) Rehd., Broussonetia papyrifera ( Linn.) L' Hér. ex Vent., Lespedeza bicolor Turcz., Caragana microphylla Lam., Rosa xanthina Lindl., Amygdalus davidiana ( Carrière) de Vos ex Henry and Periploca sepium Bunge, in which, SLA value with the largest coefficient of variation ( 404%) , and LDMC value with the lowest coefficient of variation ( 103%) . Compared with other tested species, SLA and PNUE values of E. mollis are the lowest ( 103 cm-2 · g-1 and 108 μmol · mol-1 · s-1 , respectively) , while its Narea value is the highest ( 0243 g · m-2 ) , and its LDMC value is also relatively high ( 0380 g·g-1 ) . SLA value of eight tested species show an extremely significant positive correlation ( P<001) with PNUE value, and a significant negative correlation ( P<005 ) with LDMC value, correlation coefficient are 0923 and -0718, respectively, indicating that SLA value is an important parameter of leaf photosynthetic capacity and resource utilization ability. It is suggested that compared with other dominant woody species, E. mollis is more sensitive to environmental change, and has a poor environmental adaptability.     

去除干扰对内蒙古典型草原植物叶片功能属性的影响

以内蒙古典型草原为研究对象,选取放牧和割草、去除放牧、去除放牧和割草样地进行群落调查和叶片属性测量,比较分析各样地土壤性质、群落生产力及主要物种的比叶面积(SLA,Specific Leaf Area)、叶片干物质含量(LDMC,Leaf Dry Matter Content)、叶片氮含量(LNC,Leaf Nitrogen Concentration)在个体、功能群和群落水平对去除干扰的响应。结果表明,1)去除干扰处理在短期对土壤特性和群落生产力的影响不显著;2)多数物种在放牧和割草样地SLA较低,说明典型草原多数物种的SLA表现为放牧逃避;3)不同功能群植物叶片属性对去除干扰的响应不一致,去除放牧后,多年生杂类草的SLA和LDMC不受影响,但LNC变小;多年生禾草的SLA增加,而LDMC和LNC无显著变化。一年生植物在去除放牧和割草后,LNC显著增加。去除割草后,多年生禾草SLA减小,而多年生杂类草SLA、LNC增加,LDMC减小;4)在群落水平,放牧和割草样地由于较占优势的多年生禾草SLA较低,群落比叶面积最低,在去除放牧和割草样地,群落叶片氮含量显著增加;5)在内蒙古典型草原,LDMC能够很好地将多年生禾草和多年生杂类草区分,SLA在个体、功能群和群落水平均比LDMC敏感。     

北京植物园不同功能型植物叶经济谱

通过对北京植物园不同功能型植物的叶片光合参数、叶绿素荧光参数、叶面积、叶干质量以及叶氮含量等性状参数进行测定,分析了不同功能型植物的叶经济谱.结果表明: 生活型中草本植物、生活史中一年生植物、光合型中C4植物靠近叶经济谱中快速投资-收益型物种的一端,而生活型中乔木和灌木、生活史中多年生植物、光合型中C3植物位于缓慢投资-收益型物种的一端,表明不同功能型植物通过叶片性状间的权衡采取不同的环境适应策略,验证了不同功能型植物叶经济谱的存在.不同功能型植物叶片性状具有明显差异,其中不同生活型间的叶片比叶面积(SLA)、叶氮含量(N_mass)、最大净光合速率(A_mass)、光合氮利用效率(PNUE)均表现出草本植物>藤本植物>灌木>乔木;不同生活史间一年生植物的SLA、N_mass、A_mass、PNUE均显著高于多年生植物;不同光合型间植物的A_mass、PNUE、PSⅡ实际光化学效率(Φ_PSⅡ)均表现出C4>C3.N_mass、A_mass、SLA两两之间呈显著正相关,而PSⅡ有效光化学量子产量(F_v′/F_m′)与SLA呈显著负相关;PNUE与SLA呈显著正相关.     

Diversification and phylogenetic correlation of functional traits for co-occurring understory species in the Chinese boreal forest

Functional traits impact species interactions, community composition, and ecosystem functioning. However, few studies have focused on the diversification and phylogenetic correlation of multiple functional traits over geological time. We conducted phylogenetic comparative analysis for boreal forest understory species in northeast China to examine the diversification and phylogenetic correlation in several functional traits: leaf area (LA), leaf carbon content (LCC), leaf dry matter content (LDMC), leaf nitrogen content (LNC), plant height (PH), and specific leaf area (SLA). Phylogenetic signals showed that there were very low levels of phylogenetic niche conservatism (PNC) in understory leaf-related traits and plant height, suggesting divergence of functional traits for the co-occurring understory species. The disparity through time analyses (DTT) indicated that trait disparities mainly originated during recent divergence events and there were no differences in the observed trait disparities compared with that expected under Brownian motion. Furthermore, we found both positive and negative phylogenetic correlations among the measured functional traits. The very low levels of PNC suggest that these functional traits diverged among co-occurring understory species, and that those species are distantly phylogenetically related. The phylogenetic correlations among traits may be caused by both positively and negatively correlated adaptions that correspond to resource acquisition strategies. This study provides evidence that divergence in functional traits may reflect understory adaptions to boreal conditions.     

黄土高原子午岭不同森林群落叶功能性状

对黄土高原子午岭地区5种主要森林群落中重要值>0.1的物种叶功能性状进行了比较,结果表明:1)叶干物质含量(LDMC)与比叶面积(SLA)呈负相关;SLA与叶厚度(LT)呈负相关,但与叶氮含量(LNC)和叶磷含量(LPC)呈正相关;LT与LNC、LPC和叶钾含量(LKC)呈负相关;LNC、LPC和LKC三者之间均呈正相关。2)坡位是影响叶大小(LS)、LT、LNC和LKC的主要地形因子,海拔对LPC和SLA的影响最大,而坡向则是影响LDMC的主要因子。因此,叶功能性状之间所呈现的特征及其对立地条件的适应都表现出了植物的生态策略。3)各群落间的乔木层叶功能性状均有显著差异,灌木层的叶功能性状无显著差异,而草本层除了LDMC无显著差异(P>0.05)外,其他叶功能性状均有显著差异,说明群落的叶功能性状的大小取决于群落内物种的叶功能性状及其重要值。     

翅果油树叶性特征的动态变化

以山西翼城翅果油树(Elaeagnus mollis)自然保护区的翅果油树为研究对象,利用LI-3000A叶面积测定仪测量其单叶面积,用Li-6400便携式光合作用测定系统测定单位叶面积饱和光合速率(Aaraa),用H2SO4-H2O2消煮法测定叶氮含量,计算叶性参数比叶面积(SLA)、单位叶重量饱和光合速率(Amass)、光合氮利用率(PNUE)和单位重量叶氮含量(Nmass)的值,并研究它们与径级之间的关系.结果表明:随着翅果油树径级的增加,SLA、Nmass、Aarea、Amass和PNUE值先下降后上升,当翅果油树径级为7.5 cm左右时,SLA、Nmass、Aarea、Amass和PNUE值均降到最小值,表明径级为7.5 cm左右的翅果油树其光合能力最弱、光合氮利用率较低且生存压力较大.翅果油树叶性参数是研究翅果油树种群动态变化的有效指标,可为研究翅果油树种群动态提供更为便捷的方法.     

Variations in leaf morphological and chemical traits in response to life stages,plant functional types,and habitat types in an old-growth temperate forest

Intraspecific leaf trait variations are becoming a topic of interest for many ecologists because individual-based traits are essentially the drivers of variations at the community level. Six coexisting major tree species in an old-growth temperate forest, Northeast China (i.e., Abies nephrolepis, Pinus koraiensis, Acer mono, Fraxinus mandshurica, Tilia amurensis, and Ulmus laciniata) were sampled, and three habitat types (i.e., Hab I: high soil organic carbon with a moderate slope; Hab II: low soil organic carbon with a gentle slope; and Hab III: low soil organic carbon with a strong slope) were used in the plot. We performed a two-way ANOVA to compare the specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen content (LNC), leaf phosphorus content (LPC), and leaf carbon content (LCC) between saplings (1 < DBH ≤ 5 cm) and adults (DBH ≥ 10 cm) and between habitat types within species. We simultaneously evaluated the effects of life stage, plant functional type, and habitat type on the six leaf traits. Our results showed that life stage and habitat type had varied influences on the leaf traits of the six species. Life stage was an important determinant for all leaf traits. Plant functional type was included in the best models for SLA, LNC, and LCC. Habitat type had a greater influence on LDMC than SLA. Meanwhile, habitat type had a greater influence on LNC and LPC than LCC. The correlation between leaf traits with local environmental factors varied across different plant functional types and life stages. We suggest conducting individual-based analyses of leaf trait variations according to plant functional type and life stage to understand the plant life strategies along an environmental gradient may improve understanding of the forest dynamics in an old-growth temperate forest.     

Leaf trait variation captures climate differences but differs with species irrespective of functional group

Aims To clarify whether variation in leaf traits with climate differs with scale, i.e. across species and within a species, and to detect whether plant functional group affects species-specific response.Methods Leaf dry matter content (LDMC), specific leaf area (SLA), mass- and area-based leaf N (N mass, N area) and leaf P concentrations (P mass, P area) and leaf chlorophyll concentration (SPAD) were measured for 92 woody plant species in two botanical gardens in China. The two gardens share plant species in common but differ in climate. Leaf trait variation between the two gardens was examined via mean comparison at three scales: all species together, species grouped into plant functional groups and within a species. A meta-analysis was performed to summarize the species-specific responses.Important findings At the scale of all species together, LDMC, SLA, P mass and N mass were significantly lower in the dry-cold habitat than in the wet-warm one, whereas N area and SPAD showed an inverse pattern, indicating a significant environmental effect. The meta-analysis showed that the above-mentioned patterns persisted for SLA, N area and SPAD but not for the other variables at the species-specific scale, indicating that intraspecific variation affects the overall pattern of LDMC, P mass and N mass and P area. In terms of species-specific response, positive, negative or nonsignificant patterns were observed among the 92 species. Contrary to our prediction, species-specific responses within a functional group were not statistically more similar than those among functional groups. Our results indicated that leaf trait variation captured climatic difference yet species-specific responses were quite diverse irrespective of plant functional group, providing new insights for interpreting trait variability with climate.     

Congruency analysis of species ranking based on leaf traits: which traits are the more reliable?

Nine leaf traits (area, fresh weight, dry weight, volume, density, thickness, specific leaf area (SLA), dry matter content (LDMC), leaf nitrogen content (LNC)) from ten plant species at eight sites in southern mediterranean France were investigated in order to assess their variability along a climatic gradient and their ranking congruency power. After examination of trait correlation patterns, we reduced the nine initial leaf traits to four traits, representative of three correlation groups: allometric traits (dry weight), functional traits (SLA and dry matter percentage) and Leaf Thickness. We analysed the variability of these four leaf traits at species and site level. We observed that between species variation (between 64.5 for SLA and 91% for LDMC) is higher than within species variation. Allowing a good congruency of species ranking assessed by spearman rank correlation () and a good reallocation of individuals to species by discriminant analysis. A site level variability (between 0.7% for Dry weight and 6.9% for SLA) was identified and environmental parameters (altitude, temperature, precipitation, nitrogen, pH) were considered as probable control factors. We found significant correlation between SLA, LDMC and the average minimum temperature (respectively r=0.87 and r=-0,9) and no correlation for the other traits or environmental parameters. Furthermore, we conclude that two leaf traits appear to be central in describing species: specific leaf area (SLA), percentage of dry matter (LDMC. While, SLA and LDMC are strongly correlated, LDMC appears to be less variable than SLA. According to our results the Dry Matter Content (or its reversal Leaf Water Content) appears the best leaf trait to be quantified for plant functional screening. Leaf thickness appeared to be rather uncorrelated with other leaf traits and show no environmental contingency; its variability could not have been explained in this study. Further studies should focus on this trait. This revised version was published online in June 2006 with corrections to the Cover Date.     

Do higher resource capture ability and utilization efficiency facilitate the successful invasion of native plants?

The great damage caused by native invasive species on natural ecosystems is prompting increasing concern worldwide. Many studies have focused on exotic invasive species. In general, exotic invasive plants have higher resource capture ability and utilization capacity, and lower leaf construction cost (CC) compared to noninvasive plants. However, the physiological mechanisms that determine the invasiveness of native plants are poorly understood. We hypothesized that native invaders, like exotic invaders, may have higher resource capture ability and utilization efficiency compared to native noninvaders. To test this hypothesis, ecophysiological traits including light-saturated photosynthetic rate (A_max), specific leaf area (SLA), photosynthetic nitrogen use-efficiency (PNUE), photosynthetic energy-use efficiency (PEUE), and mass-based and area-based leaf construction cost (CC_mass and CC_area) were measured. We compared the above traits between three pairs of native invasive and noninvasive native species, and between three pairs of exotic invasive and noninvasive species in Guangzhou, southern China. Our results showed that the native invaders had higher A_max, SLA, PNUE, PEUE and lower CC_mass, CC_area, compared to native noninvaders and that these traits were also found in the exotic invaders. PNUE and PEUE in the native invaders were 150.3 and 129.0% higher, respectively, than in noninvasive native species, while these same measures in exotic invaders were 43.0 and 94.2% higher, respectively, than in exotic noninvasive species. The results indicated that native invaders have higher resource capture ability and resource utilization efficiency, suggesting that these traits may be a common biological foundation underlying successful invasion by both native and exotic invasives.     

亚热带常绿落叶阔叶混交林植物功能性状的种间和种内变异

不同物种间的功能性状差异是自然生态系统中物种共存的基础, 而物种内个体间的性状变异对物种的共存和分布同样具有重要作用。本文以湖北星斗山自然保护区亚热带常绿落叶阔叶混交林内28种主要树种(通过物种多度排序获得, 其中常绿和落叶树种各14种)为研究对象, 探讨不同叶习性树种的4种功能性状(比叶面积、叶干物质含量、叶面积和比茎密度)在种间和种内的差异程度。结果表明: (1)常绿和落叶树种在4种功能性状上均存在显著差异, 常绿树种的比叶面积和叶面积显著低于落叶树种, 但叶干物质含量和比茎密度则显著高于落叶树种; (2)比叶面积的变化主要来源于叶习性(57.49%), 叶面积变化主要来源于种间(66.80%)和种内变异(27.52%), 叶干物质含量的变化主要来源于种间(38.12%)和种内(33.88%)变异, 但比茎密度的变化主要来源于种内变异(51.50%), 其次为种间变异(32.52%); (3)常绿和落叶树种种间水平的性状相关性可能掩盖各功能性状之间的相关性。种内变异能够显著影响群落间的植物功能性状差异, 但不同功能性状的种内变异程度存在差异。     

38个榛种质资源叶功能性状与光合特征变异及其相关性

研究了38个榛种质资源叶功能性状与光合特征参数的变异特征及其相关关系,为优良种质资源的选择以及进一步理解叶功能性状对光合特征的影响机制提供科学依据。结果表明:38个种质资源的叶面积(LA)、叶形指数(LI)、叶干重(LDW)、比叶面积(SLA)和叶干物质含量(LDMC)平均值分别为78.39 cm²、1.24、0.73 g、109.95 cm²·g^-1和38.31%,LDW变异最大,其次为LA和SLA,LI和LDMC变异最小;净光合速率(Pn)、蒸腾速率(Tr)、气孔导度(gs)、胞间CO2浓度(Ci)、气孔限制值(Ls)和水分利用效率(WUE)平均值分别为9.92μmol·m^-2·s^-1、3.88 mmol·m^-2·s^-1、153.04μmol·m^-2·s^-1、238.73μmol·mol^-1、0.41和2.54μmol·mmol-1,gs变异最大(27.89%),Pn、Ci、Ls和WUE次之(10.37%~15.14%),Tr最小(9.99%)。不同种质资源叶功能性状与光合特征参数之间均存在极显著差异。Pearson相关分析表明:Pn与LA、LDW、LDMC均呈显著正相关,与SLA则呈显著负相关;Tr与LA呈显著正相关;gs和Ci与LDMC分别呈显著负相关和正相关;WUE与LDW、LDMC均呈显著正相关,与SLA则呈显著负相关。冗余分析表明:第1、2排序轴共同解释了叶片光合特征总变异的88.6%,其中,对光合特征产生显著影响的叶功能性状因子为SLA和LDMC。平欧210号、F-03、平欧11号、平欧88号、平欧119号、85-162、平欧48号、玉坠、平欧110号表现出较高的水分和光能利用效率。     

海岛植物不同演替阶段植物功能性状与环境因子的变化规律

植物功能性状与环境之间的关系是功能性状研究的重点,环境因子驱使植物功能性状发生变化,进而推动群落发生演替。以平潭岛4个不同演替阶段的森林植被(灌草丛、针叶林、针阔混交林、常绿阔叶林)为研究对象,结合不同群落演替阶段的物种特征和群落结构,分析海岛不同演替阶段茎、叶功能性状的变化规律,以及功能性状与环境因子的关系。结果表明:(1)随着演替的进行,土壤养分和水分逐渐增加,土壤pH逐渐下降。比叶面积(SLA)、叶片氮含量(LNC)、叶片磷含量(LPC)、茎氮含量(SNC)、茎磷含量(SPC)下降后上升,叶厚度(LT)、叶片碳含量(LCC)、茎碳含量(SCC)与之相反,叶干物质含量(LDMC)、茎组织密度(STD)逐渐上升。(2)冗余分析表明,演替早期植物主要分布在土壤pH、容重高的贫瘠环境,拥有较高SLA、SNC、SPC、LPC的性状组合;演替后期植物主要分布在土壤养分和水分高的肥沃环境,拥有较高的STD、LDMC、LCC、LNC的性状组合。其中,土壤有机质和全氮含量是影响海岛植物演替过程中功能性状变化的关键环境因子。研究海岛植物功能性状与环境之间的关系随演替的变化规律,探讨各演替阶段功能性状和环境特征,以及功能性状如何响应环境变化。旨在为今后选择合适的树种进行海岛植被修复和重建提供依据。     

环境因子对海岛植物茎、叶功能性状的影响

植物功能性状与环境之间的关系是功能性状研究的重点,海岛作为独特的生态系统,其植物功能性状必然和大陆存在差异。为了明确海岛植被的生态适应机制,该文以平潭岛森林群落为研究对象,通过测定茎、叶10个功能性状,以及地形和土壤9个环境因子,探讨了植物功能性状之间的权衡关系,分析了环境因子对海岛植物功能性状的影响。结果表明:(1)比叶面积(SLA)与叶氮含量(LNC)、叶磷含量(LPC)呈正相关,与叶厚度(LT)、叶干物质含量(LDMC)、茎组织密度(STD)、叶碳含量(LCC)呈负相关; LDMC与LNC、茎氮含量(SNC)呈负相关; LT与STD呈正相关,与LNC和LPC呈负相关; LPC与LNC、SNC呈正相关;茎和叶C、N含量均呈正相关。(2)土壤有机质和TN是海岛植物功能性状的主要土壤影响因子。然而,由于土壤中磷含量的缺乏,LNC、茎磷含量(SPC)、SNC均与土壤全磷呈正相关; LDMC与土壤全氮呈正相关;STD与土壤有机质呈正相关; SLA随着土壤pH的增加而增加。(3)坡位和坡度是海岛植物功能性状的主要地形影响因子。SLA、SPC随着海拔上升而下降; STD、LDMC随着海拔和坡度增大而增大; LNC、LPC阴坡大于阳坡。该研究为海岛植被修复和重建提供了参考依据。     

Temporal intraspecific trait variability drives responses of functional diversity to interannual aridity variation in grasslands

Interannual climate variation alters functional diversity through intraspecific trait variability and species turnover. We examined these diversity elements in three types of grasslands in northern China, including two temperate steppes and an alpine meadow. We evaluated the differences in community‐weighted means (CWM) of plant traits and functional dispersion (FDis) between 2 years with contrasting aridity in the growing season. Four traits were measured: specific leaf area (SLA), leaf dry matter content (LDMC), leaf nitrogen concentration (LNC), and the maximum plant height (H). CWM for SLA of the alpine meadow increased in the dry year while that of the temperate steppe in Qinghai showed opposing trends. CWM of LDMC in two temperate steppes became higher and CWM of LNC in all grasslands became lower in the dry year. Compared with the wet year, FDis of LDMC in the alpine meadow and FDis of LNC in the temperate steppe in Qinghai decreased in the dry year. FDis of H was higher in the dry year for two temperate steppes. Only in the temperate steppe in Qinghai did the multi‐FDis of all traits experience a significant increase in the dry year. Most of the changes in CWM and FDis between 2 years were explained by intraspecific trait variation rather than shifts in species composition. This study highlights that temporal intraspecific trait variation contributes to functional responses to environmental changes. Our results also suggest it would be necessary to consider habitat types when modeling ecosystem responses to climate changes, as different grasslands showed different response patterns.     

Assessing the generality of global leaf trait relationships

Global-scale quantification of relationships between plant traits gives insight into the evolution of the world's vegetation, and is crucial for parameterizing vegetation-climate models. A database was compiled, comprising data for hundreds to thousands of species for the core 'leaf economics' traits leaf lifespan, leaf mass per area, photosynthetic capacity, dark respiration, and leaf nitrogen and phosphorus concentrations, as well as leaf potassium, photosynthetic N-use efficiency (PNUE), and leaf N : P ratio. While mean trait values differed between plant functional types, the range found within groups was often larger than differences among them. Future vegetation-climate models could incorporate this knowledge. The core leaf traits were intercorrelated, both globally and within plant functional types, forming a 'leaf economics spectrum'. While these relationships are very general, they are not universal, as significant heterogeneity exists between relationships fitted to individual sites. Much, but not all, heterogeneity can be explained by variation in sample size alone. PNUE can also be considered as part of this trait spectrum, whereas leaf K and N : P ratios are only loosely related.     

东灵山地区不同森林群落叶功能性状比较

植物功能性状(plant functional trait)是近年来生态学研究的热点.其中叶功能性状(leaf functional trait)与植株生物量和植物对资源的获得、利用及利用效率的关系最为密切.研究了东灵山地区叶功能性状之间的关系、叶功能性状与地形因子的关系,并对不同群落叶功能性状进行了比较.通过Pearson相关分析发现,叶干物质含量(LDMC)与比叶面积(SLA)、叶氮浓度(LNC)、叶磷浓度(LPC)、叶钾浓度(LKC)负相关;叶大小与叶厚度正相关;SLA与 LNC、LPC、LKC正相关;LNC与LPC、LKC正相关;LPC与LKC正相关.通过灰色关联度分析发现,对叶大小、LNC、LKC来讲,海拔是各项地形因子中的首要影响因子;对LDMC、叶厚度来讲,坡度对其影响最大;对SLA、LPC来讲,坡位是其首要影响因子.依据乔木层的SLA和LDMC将5种群落分成3类,第一类是黑桦林和山杨林,第二类是辽东栎林,第三类是胡桃楸林和糠椴林.群落的分类情况符合该地带性植被优势度类型的分类情况,LDMC和SLA是最能体现群落间差异的叶功能性状.     

松嫩草地66种草本植物叶片性状特征

植物叶片功能性状及其相互关系越来越受到关注.以松嫩草地66种草本植物为研究对象,测量叶片干物质含量、比叶面积、叶片厚度、叶片氮含量、叶片磷含量、叶绿素含量和类胡萝卜素含量,检验性状间的相互关系,比较不同功能群(多年生根茎禾草,多年生丛生禾草,多年生杂类草,1年生或2年生草本)间性状的差异性.结果表明,叶片厚度变异系数最大,比叶面积、叶片氮含量、叶片磷含量、叶绿素含量和类胡萝卜素含量之间存在显著的正相关关系;叶片于物质含量与叶片磷含量没有显著的相关关系,与其它叶片性状呈显著的负相关关系;叶片厚度只与叶片干物质含量和比叶面积呈显著的负相关关系,与其它叶片性状不相关.叶片干物质含量、比叶面积、叶片厚度、叶片氮、磷含量在4个功能群间差异显著,叶绿素含量和类胡萝卜素含量在各个功能群间差异不显著;多年生根茎禾草和多年生丛生禾草叶片的7个性状差异不显著;多年生根茎禾草和多年生丛生禾草的叶片干物质含量高于多年生杂类草和1年生或2年生草本,其它性状小于这两个功能群.