Variation In Leaf Functional Traits Research Articles

Facilitation drives tree seedling survival at alpine treelines

Abstract Alpine treelines are considered ecological monitors recording the impacts of climate change on trees and forests. To date, most treeline research has focused on how climate change drives treeline dynamics. However, little is known about how biotic interactions mediate treeline shifts, particularly in the case of tree recruitment, a bottleneck of treeline dynamics. We hypothesized that inter- and intraspecific facilitation determined the establishment and survival of tree seedlings at alpine treelines. To test this hypothesis, 630 Abies georgei var. smithii seedlings with different ages (4–6, 7–9 and 10–15 years old) were transplanted into three growth habitats (canopy-in, canopy-out and meadow) across the alpine treeline ecotone (4300–4500 m) in the Sygera Mountains, on the southeastern Qinghai-Tibetan Plateau. Microclimate, height growth, mortality rates and leaf functional traits of transplanted seedlings were measured over 3 years. We found that the variations in leaf functional traits were driven by microclimate. After the transplantation, the leaf concentrations of soluble sugars and starch and C:P ratio increased, whereas leaf size decreased. The resource use of seedlings gradually shifted to a more conservative strategy as indicated by changes in non-structural carbohydrates and nutrient concentrations. Radiation, temperature and moisture conditions, mediated by plant interactions, influenced seedling mortality and annual growth by affecting leaf morphological traits. Our findings illustrate how facilitation plays a crucial role in altering solar radiation and leaf trait functioning, determining seedling survival and growth at alpine treelines. We provide new insights into the underlying mechanisms for tree establishment and alpine treeline shifts in response to climate change.

Spatial variations in leaf trichomes and their coordination with stomata in Quercus variabilis across Eastern Asia

Abstract Leaf trichomes are derived from epidermal cells and serve an important function in regulating leaf heat balance and gas exchange. Variation in leaf functional traits is critical for predicting how plants will react to global climate change. In this study, we aimed to investigate how leaf trichome densities vary along large geographic gradients and how they interact with with stomata in response to environmental change. We investigated the leaf trichome densities of 44 Quercus variabilis populations in Eastern Asia (24° to 51.8° N, 99° to 137° E) and their correlation with climatic factors and stomatal traits. In addition, 15 populations were grown in a common garden to study their adaptive variation and coordination with stomata. The mean value of trichome density in situ conditions was 459.78 trichome mm-2 with a range of 325.79 to 552.38 trichome mm-2. Trichome density increased with latitude and decreased with longitude. Both temperature and precipitation reduced the trichome density. Moreover, trichome density was positively correlated with stomatal density whether in situ or in the common garden, and both increased with drought. Our results suggested that leaf trichomes possess highly adaptive variation and are in close coordination with stomata in response to climate change. Our findings provide new insights toward elucidating the interactions between leaf traits and the adaptive strategies of plants under climate change.

Foliar spectra accurately distinguish most temperate tree species and show strong phylogenetic signal.

Spectroscopy is a powerful remote sensing tool for monitoring plant biodiversity over broad geographic areas. Increasing evidence suggests that foliar spectral reflectance can be used to identify trees at the species level. However, most studies have focused on only a limited number of species at a time, and few studies have explored the underlying phylogenetic structure of leaf spectra. Accurate species identifications are important for reliable estimations of biodiversity from spectral data. Using over 3500 leaf-level spectral measurements, we evaluated whether foliar reflectance spectra (400-2400 nm) can accurately differentiate most tree species from a regional species pool in eastern North America. We explored relationships between spectral, phylogenetic, and leaf functional trait variation as well as their influence on species classification using a hurdle regression model. Spectral reflectance accurately differentiated tree species (κ = 0.736, ±0.005). Foliar spectra showed strong phylogenetic signal, and classification errors from foliar spectra, although present at higher taxonomic levels, were found predominantly between closely related species, often of the same genus. In addition, we find functional and phylogenetic distance broadly control the occurrence and frequency of spectral classification mistakes among species. Our results further support the link between leaf spectral diversity, taxonomic hierarchy, and phylogenetic and functional diversity, and highlight the potential of spectroscopy to remotely sense plant biodiversity and vegetation response to global change.

Vertical variation in leaf functional traits of Parashorea chinensis with different canopy layers.

Canopy species need to shift their ecological adaptation to improve light and water resources utilization, and the study of intraspecific variations in plant leaf functional traits based at individual scale is of great significance for evaluating plant adaptability to climate change. In this study, we evaluate how leaf functional traits of giant trees relate to spatial niche specialization along a vertical gradient. We sampled the tropical flagship species of Parashorea chinensis around 60 meters tall and divided their crowns into three vertical layers. Fourteen key leaf functional traits including leaf morphology, photosynthetic, hydraulic and chemical physiology were measured at each canopy layer to investigate the intraspecific variation of leaf traits and the interrelationships between different functional traits. Additionally, due to the potential impact of different measurement methods (in-situ and ex-situ branch) on photosynthetic physiological parameters, we also compared the effects of these two gas exchange measurements. In-situ measurements revealed that most leaf functional traits of individual-to-individual P. chinensis varied significantly at different canopy heights. Leaf hydraulic traits such as midday leaf water potential (MWP) and leaf osmotic potential (OP) were insignificantly correlated with leaf photosynthetic physiological traits such as maximal net assimilation rate per mass (A mass). In addition, great discrepancies were found between in-situ and ex-situ measurements of photosynthetic parameters. The ex-situ measurements caused a decrease by 53.63%, 27.86%, and 38.05% in A mass, and a decrease of 50.00%, 19.21%, and 27.90% in light saturation point compared to the in-situ measurements. These findings provided insights into our understanding of the response mechanisms of P. chinensis to micro-habitat in Xishuangbanna tropical seasonal rainforests and the fine scale adaption of different resultant of decoupled traits, which have implications for understanding ecological adaption strategies of P. chinensis under environmental changes.

Leaf functional traits vary among growth forms and vegetation zones in the Himalaya

Compression of life zones along elevational gradients in mountains supports diverse vegetation types, and therefore offers ideal setting to study plant functional traits. Functional traits, the features that enable plants to live in varied environmental conditions, help in understanding ecological interactions, evolutionary adaptations, and predicting plant response to global change drivers. To date, little is known how the trait diversity varies across different growth forms and vegetation zones in mountains. Here, we aimed to investigate interspecific leaf trait variability among different growth forms and vegetation zones along a wide elevation gradient (2000–4200 m) in Kashmir Himalaya. We measured leaf functional traits (specific leaf area—SLA, leaf thickness — LT, leaf dry matter content —LDMC) of 76 plant species corresponding to three growth forms (trees, shrubs and herbs) and three vegetation zones (Himalayan dry temperate forests, subalpine forests and alpine grasslands). Our results revealed high trait variability across the regional species pool studied. We found significant variation in leaf functional traits among the different growth forms, with higher values of LT and LDMC recorded for woody species than herbaceous ones. Among different vegetation zones, the SLA was found to be significantly higher at lower to middle elevations, while the other leaf traits (LT and LDMC) showed an opposite trend. Across all the vegetative zones, we also found a negative correlation between SLA and the other leaf traits, and the latter showed a positive trait-trait correlation. Overall, our study contributes to a deeper understanding of trait-trait, trait-growth form and trait-vegetation zone relationships. Our findings suggest that the variation in leaf functional traits among different growth forms seems to be a trade-off mechanism between resource acquisition and leaf construction, and also help in identifying species' adaptive functional traits that are critical for plant survival in the face of ongoing climate change in the Himalaya.

Plant economic strategies in two contrasting forests

BackgroundPredicting relationships between plant functional traits and environmental effects in their habitats is a central issue in terms of classic ecological theories. Yet, only weak correlation with functional trait composition of local plant communities may occur, implying that some essential information might be ignored. In this study, to address this uncertainty, the objective of the study is to test whether and how the consistency of trait relationships occurs by analyzing broad variation in eight traits related to leaf morphological structure, nutrition status and physiological activity, within a large number of plant species in two distinctive but comparable harsh habitats (high-cold alpine fir forest vs. north-cold boreal coniferous forest).ResultsThe contrasting and/or consistent relationships between leaf functional traits in the two distinctive climate regions were observed. Higher specific leaf area, photosynthetic rate, and photosynthetic nitrogen use efficiency (PNUE) with lower N concentration occurred in north-cold boreal forest rather than in high-cold alpine forest, indicating the acquisitive vs. conservative resource utilizing strategies in both habitats. The principal component analysis illuminated the divergent distributions of herb and xylophyta groups at both sites. Herbs tend to have a resource acquisition strategy, particularly in boreal forest. The structural equation modeling revealed that leaf density had an indirect effect on PNUE, primarily mediated by leaf structure and photosynthesis. Most of the traits were strongly correlated with each other, highlighting the coordination and/or trade-offs.ConclusionsWe can conclude that the variations in leaf functional traits in north-cold boreal forest were largely distributed in the resource-acquisitive strategy spectrum, a quick investment-return behavior; while those in the high-cold alpine forest tended to be mainly placed at the resource-conservative strategy end. The habitat specificity for the relationships between key functional traits could be a critical determinant of local plant communities. Therefore, elucidating plant economic spectrum derived from variation in major functional traits can provide a fundamental insight into how plants cope with ecological adaptation and evolutionary strategies under environmental changes, particularly in these specific habitats.

Variations and driving factors of leaf functional traits in the dominant desert plant species along an environmental gradient in the drylands of China

Leaf functional traits (LFTs) of desert plants are responsive, adaptable and highly plastic to their environment. However, the macroscale variation in LFTs and driving factors underlying this variation remain unclear, especially for desert plants. Here, we measured eight LFTs, including leaf carbon concentration (LCC), leaf nitrogen concentration (LNC), leaf phosphorus concentration (LPC), specific leaf area (SLA), leaf dry matter content (LDMC), leaf mass per area (LMA), leaf thickness (LTH) and leaf tissue density (LTD) across 114 sites along environmental gradient in the drylands of China and in Guazhou Common Garden and evaluated the effect of environment and phylogeny on the LFTs. We noted that for all species, the mean values of LCC, LNC, LPC, SLA, LDMC, LMA, LTH and LTD were 384.62 mg g−1, 19.91 mg g−1, 1.12 mg g−1, 79.62 cm2 g−1, 0.74 g g−1, 237.39 g m−2, 0.38 mm and 0.91 g cm−3, respectively. LFTs exhibited significant geographical variations and the LNC, LMA and LTH in the plants of Guazhou Common Garden were significantly higher than the field sites in the drylands of China. LDMC and LTD of plants in Guazhou Common Garden were, however, considerably lower than those in the drylands of China. LCC, LPC, LTH and LTD differed significantly among different plant lifeforms, while LNC, SLA, LDMC and LMA didn't show significant variations. We found that the environmental variables explained higher spatial variations (3.6–66.3 %) in LFTs than the phylogeny (1.8–54.2 %). The LCC significantly increased, while LDMC and LTD decreased with increased temperature and reduced precipitation. LPC, LDMC, LMA, and LTD significantly increased, while SLA and LTH decreased with increased aridity. However, leaf elements were not significantly correlated with soil nutrients. The mean annual precipitation was a key factor controlling variations in LFTs at the macroscale in the drylands of China. These findings will provide new insights to better understand the response of LFTs and plants adaptation along environmental gradient in drylands, and will serve as a reference for studying biogeographic patterns of leaf traits.

Intraspecific variations in leaf functional traits of Cunninghamia lanceolata provenances

BackgroundStudies on intra-specific variability in leaf functional traits is important to evaluate adaptation of the species to predicted climate change, and to develop long-term conservation strategy. The main objectives were to investigate the relationship between the functional traits leaves and C, N, P stoichiometry of Chinese fir from different geographical provenances and their relationship with the main environmental factors of provenance.ResultsIn this study, we measured 12 leaf functional traits on 36-year-old Cunninghamia lanceolata trees from 13 provenances. Analysis of variance (ANOVA) was performed to examine the variability. Redundancy analysis (RA) was computed to examine the relationship between geo-climatic factors of provenance origin and leaf functional traits while Pearson’s correlation coefficient was computed to assess inter-trait correlations. The results showed statistically significant differences (P < 0.01) in intraspecific leaf traits among provenances, except leaf P content. The relationships among leaf traits are consistent with the general trend observed in the leaf economic spectrum. Mean annual temperature appeared to be a key factor that influences intraspecific leaf traits variability compared to mean annual precipitation.ConclusionThese results provide useful insights about adaptation of leaf trait of Chinese fir in a changing climatic condition. Thus, our findings shed light on the importance of interspecific trait variability in Chinese fir and the potential effect of climate change.

Altitudinal Variations in Leaf Functional Traits of some Woody Species in the Savannahs of Ngaoundere (Adamaoua, Cameroon)

In order to contribute to the sustainable management of the Ngaoundere savannahs, experiments in natural environments were carried out to assess interspecific and altitudinal variations in leaf functional traits. To do this, 20 leaves per plant were collected from 7 individuals per species, giving a total of 140 leaves per species for each of the three sites (Dang, Tchabbal and the Cliff) in the Ngaoundere Cameroon savannahs. The leaves were photographed and the images were processed using image j software to estimate leaf area. The data obtained related to certain traits such as dry mass, leaf area, thickness, leaf specific area, specific mass, dry matter content and leaf density. For each of the three sites, dry mass decreased significantly with increasing altitude, from 1.12 g at the Dang site to 0.68 g at the Cliff site. Overall, the water content is higher at the Cliff (47.33%) and lower at Tchabbal (41.93%). Thickness increases with altitude, rising from 0.20 mm at low altitudes (Dang) to 0.30 mm at high altitudes (at the Cliff) and intermediate (0.25 mm) at medium altitudes (Tchabbal). Leaf area decreased significantly with increasing altitude, from 70.45 cm2 at low altitudes (Dang) to 53.05 cm2 at high altitudes (at the Cliff) and intermediate (57.70 cm2) at medium altitudes (Tchabbal). The leaf specific area decreases significantly with altitude, from 115.95 cm2/g at the Dang site to 78.16 cm2/g at the Cliff. Dry matter content increased with altitude, rising from 0.30 g/g at Dang to 0.58 g/g at the Cliff. Specific mass increased with altitude, rising from 0.00 g/cm2 at Dang to 0.02 g/cm2 at the Cliff. Leaf density increased with altitude, from Dang (0.06 g/mm3) to the Cliff (0.10 g/mm3). Finally, the height of the woody plants decreased with altitude, from 5.08 m at Dang to 3.80 m at the Cliff. Overall, leaf traits decreased with altitude, except for thickness and density. These results would thus contribute to an understanding of the functioning of savannah ecosystems in general, and those of Ngaoundere in particular, with a view to their sustainable management.

Vertical variations in leaf functional traits of three typical ferns in mixed broadleaved- Korean pine forest

Vertical variations in leaf functional traits of three typical ferns in mixed broadleaved- Korean pine forest

Linking Leaf Functional Traits with Soil and Climate Factors in Forest Ecosystems in China.

Plant leaf functional traits can reflect the adaptive strategies of plants to environmental changes. Exploring the patterns and causes of geographic variation in leaf functional traits is pivotal for improving ecological theory at the macroscopic scale. In order to explore the geographical variation and the dominant factors of leaf functional traits in the forest ecosystems of China, we measured 15 environmental factors on 16 leaf functional traits in 33 forest reserves in China. The results showed leaf area (LA), carbon-to-nitrogen ratio (C/N), carbon-to-phosphorus ratio (C/P), nitrogen-to-phosphorus ratio (N/P), phosphorus mass per area (Pa) and nitrogen isotope abundance (δ15N)) were correlated with latitude significantly. LA, Pa and δ15N were also correlated with longitude significantly. The leaf functional traits in southern China were predominantly affected by climatic factors, whereas those in northern China were mainly influenced by soil factors. Mean annual temperature (MAT), mean annual precipitation (MAP) and mean annual humidity (MAH) were shown to be the important climate factors, whereas available calcium (ACa), available potassium (AK), and available magnesium (AMg) were shown to be the important climate factors that affect the leaf functional traits of the forests in China. Our study fills the gap in the study of drivers and large-scale geographical variability of leaf functional traits, and our results elucidate the operational mechanisms of forest-soil-climate systems. We provide reliable support for modeling global forest dynamics.

Effect of Salinity on Leaf Functional Traits and Chloroplast Lipids Composition in Two C3 and C4 Chenopodiaceae Halophytes.

Salt stress is one of the most common abiotic kinds of stress. Understanding the key mechanisms of salt tolerance in plants involves the study of halophytes. The effect of salinity was studied in two halophytic annuals of Chenopodiaceae Salicornia perennans Willd. and Climacoptera crassa (Bied.) Botsch. These species are plants with C3 and C4-metabolism, respectively. We performed a comprehensive analysis of the photosynthetic apparatus of these halophyte species at different levels of integration. The C3 species S. perennans showed larger variation in leaf functional traits—both at the level of cell morphology and membrane system (chloroplast envelope and thylakoid). S. perennans also had larger photosynthetic cells, by 10–15 times, and more effective mechanisms of osmoregulation and protecting cells against the toxic effect of Na+. Salinity caused changes in photosynthetic tissues of C. crassa such as an increase of the mesophyll cell surface, the expansion of the interface area between mesophyll and bundle sheath cells, and an increase of the volume of the latter. These functional changes compensated for scarce CO2 supply when salinity increased. Overall, we concluded that these C3 and C4 Chenopodiaceae species demonstrated different responses to salinity, both at the cellular and subcellular levels.

Variation in leaf traits among and within dominant shrubs of contrasting Pine Barrens habitats

Leaf anatomical and physiological traits influence rates of individual plant and ecosystem function. Although leaf trait variation among different species can be largely attributed to broad climatic gradients, variation at finer spatial scales and within species is less known for many habitats and taxa. Pine barrens are particularly understudied despite regional and ecological significance in northeastern North America. We assessed variation in specific leaf area (SLA), leaf dry matter content (LDMC) and leaf thickness (Lth) for three dominant understory shrub species in the New Jersey Pine Barrens. We hypothesized that traits would vary among and within species along an environmental gradient from upland forest to lowland bog. We further hypothesized that SLA would be larger and LDMC and Lth would be smaller in the upland forest than in the wetter, more nutrient-poor bog, reflective of stress tolerant plant strategies. Unexpectedly, all three species had smaller SLA and larger Lth in the forest than in the bog. LDMC was larger in the forest for Black Huckleberry (Gaylussacia baccata) and Sweetgale (Myrica gale) but smaller in the forest for Lowbush Blueberry (Vaccinium angustifolium). A trade-off between SLA and Lth appears constrained and potentially adaptive in multiple ecological contexts. However, trait-trait correlations involving LDMC were inconsistent across scales. These shrub species may be responding in similar ways to dominant environmental variables in the bog, while multiple environmental variables in the forest may promote species-specific responses and divergent trait correlations. Differences in light and water availability may be influencing leaf trait variation more than soil nutrient availability, while soil pH may be an additional driver of variation in leaf functional traits for these understory temperate shrubs.

Broad‐ and small‐scale environmental gradients drive variation in chemical, but not morphological, leaf traits of vascular epiphytes

Abstract Variation in leaf functional traits along environmental gradients can reveal how vascular epiphytes respond to broad‐ and small‐scale environmental gradients. Along elevational gradients, both temperature and precipitation likely play an important role as drivers of leaf trait variation, but these traits may also respond to small‐scale changes in light, temperature and humidity along the vertical environmental gradient within forest canopies. However, the relative importance of broad‐ and small‐scale environmental gradients as drivers of variation in leaf functional traits of vascular epiphytes is poorly understood. Here, we examined variation in morphological and chemical leaf traits of 102 vascular epiphyte species spanning two environmental gradients along Cofre de Perote mountain in Mexico: (i) a broad‐scale environmental gradient approximated by elevation as well as by species' lower and upper elevational limits, and (ii) small‐scale environmental gradients using the relative height of attachment of an epiphyte on a host tree as a proxy for variation in environmental conditions within the forest canopy. We also assessed whether variation in morphological and chemical leaf traits along these gradients was consistent across photosynthetic pathways (CAM and C3). Broad‐ and small‐scale environmental gradients explained more variation in chemical traits (marginal R2: 11%–89%) than in morphological traits (marginal R2: 2%–31%). For example, leaf carbon isotope signatures (δ13C), which reflects water‐use efficiency, varied systematically across both environmental gradients, suggesting a decrease in water‐use efficiency with increasing lower and upper elevational limits and an increase in water‐use efficiency with relative height of attachment. The influence of lower and upper elevational limits on trait variation differed between photosynthetic pathways, except for leaf dry matter content and leaf nitrogen‐to‐phosphorus ratio. Contrary to our expectations, broad‐ and small‐scale environmental gradients explained minimal variation in morphological leaf traits, suggesting that environmental conditions do not constrain morphological leaf trait values of vascular epiphytes. Our findings suggest that assessing multiple drivers of leaf trait variation among photosynthetic pathways is key for disentangling the mechanisms underlying responses of vascular epiphytes to environmental conditions. Read the free Plain Language Summary for this article on the Journal blog.

Intraspecific trait variation of grassland species in response to grazing depends on resource acquisition strategy

AbstractQuestionGrazing is an important disturbance for maintenance of structure and functioning of the plant communities in grassy ecosystems. Functional characteristics of plants, which are responsible for their response to grazing, vary at inter‐ and intraspecific levels. Here, we assessed: (1) the extent of intraspecific trait variation when compared to interspecific variability; and (2) how grazing regime affects intraspecific trait variation in leaf functional traits of species with different leaf economics strategies.LocationA multisite grazing experiment in subtropical grasslands, southern Brazil.MethodsFor 30 dominant grassland plant species we measured functional traits related to resource acquisition strategy and grazing response (SLA, specific leaf area; LDMC, leaf dry matter content; LA, leaf area; and FT, leaf resistance to traction) under three grazing treatments (grazing exclusion, traditional, or deferred grazing) arranged in a randomized block design. We quantified the overall proportion of intra‐ and interspecific variation and, for each species, we tested for the grazing treatment effects on intraspecific trait variation through Bayesian analysis of variance.ResultsThe overall contribution of intraspecific variation was up to 37% of the total variation. For most grass species, grazing exclusion led to lower values of SLA and higher values of LA, while no effect of grazing treatments was detected on intraspecific variation of LDMC and FT. Altogether, the effect of grazing management on intraspecific trait variation was more prevalent in species presenting a conservative strategy than in species with an acquisitive strategy.ConclusionThe expression of leaf traits is variable within species, especially for those species with a conservative strategy of resource acquisition. The extent of intraspecific trait variation in response to grazing depends on the considered traits and the resource acquisition strategy of the studied species.

Phylogenetic independence in the variations in leaf functional traits among different plant life forms in an arid environment

Leaf traits of global plants reveal the fundamental trade-offs in plant resource acquisition to conservation strategies. However, which leaf traits are consistent, converged, or diverged among herbs, shrubs, and subshrubs in an arid environment remains unclear. In the present study, we evaluated the trade-offs in six leaf functional traits (LFTs): leaf fresh mass (LFM), leaf dry mass (LDM), leaf dry matter content (LDMC), leaf area (LA), specific leaf area (SLA), and leaf thickness (LTh) of 37 desert plant species. LFTs differed between different plant life forms; LFM, LDM, and LA were slightly higher in herbs, LDMC and LTh in shrubs, and SLA in subshrubs. Conversely, the correlations among LFTs were inconsistent in different life forms, which may indicate their different adaptation strategies in an arid environment. Legumes and C3 plants exhibited slightly higher LDMC, LA, and SLA than non-legumes and C4 plants, whereas non-legumes and C4 plants showed higher (nonsignificant) LFM, LDM, and LTh than legumes and C3 plants. A significant phylogenetic signal (PS) and maximum K-value were found for SLA (K = 0.32). LFTs exhibited convergent and divergent variations among different life forms. However, these variations in LFTs were not influenced by phylogeny. Together, these findings increase our understanding of the variations in ecological adaptations of desert plants as well as adaption strategies of different life forms in an arid environment.

柯-青冈常绿阔叶林优势树种叶片性状变异及适应策略

PDF HTML阅读 XML下载 导出引用 引用提醒 柯-青冈常绿阔叶林优势树种叶片性状变异及适应策略 DOI: 10.5846/stxb202103100659 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 湖南省教育厅重点项目（17A227）；国家自然科学基金青年科学基金项目（31901136） Variation in leaf functional traits and adaptation strategies of dominant tree species in a Lithocarpus glaber-Cyclobalanopsis glauca evergreen broad-leaved forest Author: Affiliation: Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:厘清叶片功能性状的变异及性状间的权衡关系，对揭示植物对环境变化的响应及适应策略具有重要意义。以中亚热带柯(Lithocarpus glaber)-青冈(Cyclobalanopsis glauca)常绿阔叶林为对象，测量了1 hm2固定监测样地内6个优势树种的叶面积(LA)、比叶面积(SLA)、干物质含量(LDMC)、叶片厚度(LT)、叶片碳(LC)、叶片氮(LN)、叶片磷(LP)含量和叶片碳氮比(LC ∶ LN)8个功能性状，采用多重比较、主成分分析(PCA)法分析了群落叶片功能性状的生活型、种内和种间变异及性状间关系。结果表明：(1)群落内叶片功能性状种内、种间差异显著，变异中等(CV： 0.02-0.59)，其结构性状的可塑性较化学性状保守，变异格局符合"性状空间变异分割假说"；针叶树种的LA、SLA显著低于阔叶树种，常绿树种的LC和LDMC最小，而落叶树种的SLA、LN和LP最大以及LT和LC ∶ LN最小。(2)群落叶片功能性状变异主要来源于生活型和种间变异，种内变异亦有显著贡献；生活型对多数性状的贡献率较大，其对LDMC、LC ∶ LN的贡献分别高达93.11%和91.76%；种间变异(LDMC除外)对结构性状的贡献率均高于化学性状；种内变异对LP的贡献率(23.66%)较种间变异高。(3)叶片性状之间多表现出显著相关关系，针叶树和阔叶树在PCA排序图中聚集于不同区域，叶经济型谱在柯-青冈群落中具有适用性。不同树种通过叶片结构、化学性状之间的权衡策略来适应环境变化，从而实现群落物种共存。结果可为理解森林群落物种的环境适应策略、预测群落动态变化和制定植被恢复措施提供科学依据。 Abstract:Elucidating the variation in leaf functional traits and the trade-off relationships among those traits are of great significances to reveal the response mechanism's and adaptation strategies of plants towards changing environment. The variation of plant functional traits organically links the species adaptation strategy with the ecosystem functions and processes, and the ranges including interspecific and intraspecific variations vary with species and are closely related to environmental gradients. Meanwhile, the leaf economics spectrum (LES) at the global scale can reflects the trade-off relationships between the main structural, chemical and physiological traits. However, local community puts environmental factors and functional traits in the same system, and the main reasons responsible for the variation in functional traits and the applicability of LES still need to be deeply investigated. In this study, we collected 8 leaf functional traits of 6 dominant tree species in a 1 ha permanent monitoring plot of a Lithocarpus glaber-Cyclobalanopsis glauca subtropical evergreen broad-leaved forest, and the studied traits included leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf thickness (LT), leaf carbon (LC), leaf nitrogen (LN), leaf phosphorus (LP) content and carbon-nitrogen ratio (LC :LN). We used multiple comparison and principal component analysis (PCA) to explore the variation in leaf functional traits at the interspecific, intraspecific and life form levels, and to analyze the relationship among those functional traits. The results showed that:(1) Leaf functional traits were significantly different at the intraspecific and interspecific levels in this community. There was a moderate variation with a coefficient variation (CV) ranging from 0.02 to 0.59, and the structural traits were more conservative than chemical traits. The variation pattern of leaf functional traits conformed to "a spatial trait variance partitioning hypothesis". Leaf functional traits significantly differed among life forms, with lower SLA and LA for coniferous tree species compared to those for broad-leaved tree species, lowest LC and LDMC for evergreen trees, yet the deciduous tree species exhibited the highest SLA, LN and LP along with the lowest LT and LC :LN. (2) Life form and interspecific differences contributed the most to the variation in leaf functional traits, and intraspecific differences also contribute significantly to those variations with lower contribution rate. Life forms had relative higher contribution to the variation in most functional traits with the contribution rate reaching 93.11% and 91.76% for LDMC and LC:LN, respectively. The contribution rate of interspecific variation (except LDMC) to structural traits was higher than that to chemical traits. Intraspecific variation had a higher contribution rate to LP (23.66%) than interspecific variation. (3) There was a significant correlation between leaf functional traits. Conifers and broad-leaved trees clustered in different areas of PCA ordination chart. The leaf economics spectrum was applicable in the subtropical evergreen broad-leaved forest, and diverse tree species could coexist in this community by the trade-off strategies among leaf structural and chemical traits. The results could provide a scientific basis for understanding the adaptation strategies of diverse tree species to environment, predicting the dynamic changes of community and formulating vegetation restoration strategy. 参考文献 相似文献 引证文献

基于树形结构的木棉叶功能性状差异性研究

PDF HTML阅读 XML下载 导出引用 引用提醒 基于树形结构的木棉叶功能性状差异性研究 DOI: 10.5846/stxb202006031431 作者: 作者单位: 作者简介: 通讯作者: 中图分类号: 基金项目: 国家自然科学基金项目（31860206） Variation in leaf functional traits of Bombax ceiba Linnaeus communities based on tree structure Author: Affiliation: Fund Project: The National Natural Science Foundation of China (General Program, Key Program, Major Research Plan) 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:叶功能性状不仅反应植物对资源的利用能力，还涉及植物对自身结构和环境的生存适应策略。以不同生长阶段的木棉为研究对象，于2019年12月实地测量树高、冠幅等5个主要树形因子和采样测定叶面积、比叶面积、叶干物质含量、叶片含水量等14个叶功能性状，分析其在不同生长阶段的变化规律和相互关系，探讨叶功能性状对树形结构的响应。结果表明：不同生长阶段的木棉叶功能性状之间存在差异（P<0.05），且表现出一定的相关性（P<0.05，P<0.01）；木棉叶片的面积、长度、宽度、周长、鲜重、饱和重、干重、比叶质量和干物质含量等功能性状是随生长阶段变化的主要指标。影响木棉叶片各性状的树形因子也不相同，其中叶面积主要受到冠幅的影响，叶片鲜重和饱和重主要受到枝下高的影响，叶片干重和相对含水量主要受到树高的影响，比叶面积、叶片含水量和干物质含量主要受到树高、尖削度的影响，比叶质量主要受到胸径、尖削度、树高的影响。随着木棉的生长，叶功能性状表现出受树形结构的影响而具有较强的表型可塑性，有利于其适应内外环境的变化。因此，叶功能性状之间的变化差异和相关组合，反映了不同生长阶段的木棉对树形结构的适应性调整和对资源的利用策略，在一定程度上为探索西双版纳热带雨林区的生态保护和可持续发展提供相关科学依据。 Abstract:The leaf functional traits of plants not only reflect their abilities to use resources, but also represent their adaptation strategies to structural and environmental changes. Therefore, leaf functional traits are critical indicators of biogeochemical coupling in terrestrial ecosystems. In the present study, Bombax ceiba Linnaeus at different growth stages was taken as the main research subject, five main tree shape factors (i.e., height and crown breadth) were measured, and 14 leaf functional traits were quantified, including leaf area, specific leaf area, leaf dry matter content and leaf water content. We conducted the research in Menglun Town, Mengla County, Xishuangbanna Autonomous Prefecture in December 2019. We analyzed the changing patterns and mutual relations at different growth stages, and explored the responses of leaf functional traits to tree structure based on a variety of statistical analysis methods (i.e., One-way analysis of variance and multiple linear stepwise regression analysis). The results showed that leaf functional traits of Bombax ceiba Linnaeus differed in different growth periods (from primary growth stage to tertiary growth stage)(P<0.05), although they were also correlated certainly (P<0.05,P<0.01). Principal component analysis showed that leaf area, leaf length, leaf width, leaf perimeter, leaf fresh weight, leaf saturated weight, leaf dry weight, leaf mass per area, and leaf dry matter content were the main indicators with the increasing growth stage. The pattern of leaf functional traits was affected by various tree factors, which formed the best functional combination through the functional coordination among multiple characters so that plants could well adapt to environmental changes. We found that leaf area was mainly affected by the crown breadth. The leaf fresh weight and leaf saturated weight were mainly affected by the height to crown base. The leaf dry weight and leaf relative water content were mainly affected by the height, specific leaf area, leaf water content and leaf dry matter content were mainly affected by the height and taperingness, and leaf mass per area was mainly affected by the diameter, taperingness and height. With the growth of Bombax ceiba Linnaeus, the leaf functional traits showed strongly phenotypic plasticity influenced by tree structure, which was helpful to adapt to the changes in internal and external environment. Therefore, the variation and related combinations of leaf functional traits at different periods reflect the adaptability of Bombax ceiba Linnaeus to the tree structure and resource utilization strategies, which to a certain extent also provide relevant scientific basis for the exploration of the ecological protection and sustainable development of the tropical rain forest in Xishuangbanna. 参考文献 相似文献 引证文献

Trade-Off Relationships of Leaf Functional Traits of Lycium ruthenicum in Response to Soil Properties in the Lower Reaches of Heihe River, Northwest China

Soil properties affect plant growth and cause variation in leaf functional traits. Lycium ruthenicum Murray is one of the desert dominant shrubs and halophytes in the lower reaches of Heihe River, Northwest China. We analyzed the trade-off relationships of 14 leaf functional traits of eight L. ruthenicum populations growing at varying distances from the river and discussed the effects that soil properties have on leaf functional traits. The results showed that: Lower leaf nitrogen (N) content indicated that L.ruthenicum was located at the slow investment–return axis of the species resource utilization graph. Compared with non-saline and very slightly saline habitats, populations of slightly saline habitats showed a higher carbon to nitrogen ratio (C:N). Redundancy analysis (RDA) revealed a relatively strong relationship between leaf functional traits and soil properties, the first RDA axis accounted for 70.99 and 71.09% of the variation in 0–40 and 40–80 cm of soil properties. Relative importance analysis found that in the 0–40 cm soil layer, leaf traits variations were mainly influenced by soil moisture (SWC), HCO3− and CO32− ions content, while leaf traits variations in the 40–80 cm soil layer were mainly influenced by HCO3− and SO42−. L.ruthenicum has a foliar resource acquisition method and a resource conservation trade-off with a flexible life history strategy in habitats with drought and salinity stress. In the shallow soil layers, water affects leaf traits variation greater than salt, and in both shallow and deep soil layers, HCO3− plays a dominant role on leaf traits. This study provides insights into the adversity adaptation strategies of desert plants and the conservation and restoration of arid-saline ecosystems.

Genetic differentiation in functional traits among wild cherry (Prunus avium L.) half-sib lines

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 CO2 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.