scholarly journals Scaling of petiole anatomies, mechanics and vasculatures with leaf size in the widespread Neotropical pioneer tree species Cecropia obtusa Trécul (Urticaceae)

2020 ◽  
Vol 40 (2) ◽  
pp. 245-258 ◽  
Author(s):  
Sébastien Levionnois ◽  
Sabrina Coste ◽  
Eric Nicolini ◽  
Clément Stahl ◽  
Hélène Morel ◽  
...  
Keyword(s):  
Leaf Area ◽  
Leaf Size ◽  
Leaf Traits ◽  
Hydraulic Efficiency ◽  
Cross Sectional ◽  
Leaf Trait ◽  
Key Factor ◽  
Leaf Economic Spectrum ◽  
Geometrical Effect ◽  
Trait Variability

Abstract Although the leaf economic spectrum has deepened our understanding of leaf trait variability, little is known about how leaf traits scale with leaf area. This uncertainty has resulted in the assumption that leaf traits should vary by keeping the same pace of variation with increases in leaf area across the leaf size range. We evaluated the scaling of morphological, tissue-surface and vascular traits with overall leaf area, and the functional significance of such scaling. We examined 1,271 leaves for morphological traits, and 124 leaves for anatomical and hydraulic traits, from 38 trees of Cecropia obtusa Trécul (Urticaceae) in French Guiana. Cecropia is a Neotropical genus of pioneer trees that can exhibit large laminas (0.4 m2 for C. obtusa), with leaf size ranging by two orders of magnitude. We measured (i) tissue fractions within petioles and their second moment of area, (ii) theoretical xylem hydraulic efficiency of petioles and (iii) the extent of leaf vessel widening within the hydraulic path. We found that different scaling of morphological trait variability allows for optimisation of lamina display among larger leaves, especially the positive allometric relationship between lamina area and petiole cross-sectional area. Increasing the fraction of pith is a key factor that increases the geometrical effect of supportive tissues on mechanical rigidity and thereby increases carbon-use efficiency. We found that increasing xylem hydraulic efficiency with vessel size results in lower leaf lamina area: xylem ratios, which also results in potential carbon savings for large leaves. We found that the vessel widening is consistent with hydraulic optimisation models. Leaf size variability modifies scaling of leaf traits in this large-leaved species.

scholarly journals Ramification has little impact on shoot hydraulic efficiency in the sexually dimorphic genus Leucadendron (Proteaceae)

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e6835 ◽  
Author(s):  
Adam B. Roddy ◽  
Justin J. van Blerk ◽  
Jeremy J. Midgley ◽  
Adam G. West
Keyword(s):  
Leaf Area ◽  
Hydraulic Resistance ◽  
Leaf Traits ◽  
Sexually Dimorphic ◽  
Hydraulic Efficiency ◽  
Cross Sectional ◽  
In Series ◽  
Males And Females ◽  
Morphological Differences ◽  
The Impact

Despite the diversity of branching architectures in plants, the impact of this morphological variation on hydraulic efficiency has been poorly studied. Branch junctions are commonly thought to be points of high hydraulic resistance, but adjustments in leaf area or xylem conduit abundance or dimensions could compensate for the additional hydraulic resistance of nodal junctions at the level of the entire shoot. Here we used the sexually dimorphic genus Leucadendron (Proteaceae) to test whether variation in branch ramification impacts shoot hydraulic efficiency. We found that branch ramification was related to leaf traits via Corner’s rules such that more highly ramified shoots had smaller leaves, but that branch ramification had little consistent impact on shoot hydraulic efficiency, whether measured on a leaf area or stem cross-sectional area basis. These results suggest that the presumed increase in resistance associated with branching nodes can be compensated by other adjustments at the shoot level (e.g. leaf area adjustments, increased ramification to add additional branches in parallel rather than in series) that maintain hydraulic efficiency at the level of the entire shoot. Despite large morphological differences between males and females in the genus Leucadendron, which are due to differences in pollination and reproduction between the sexes, the physiological differences between males and females are minimal.

scholarly journals Distinct Responses of Leaf Traits to Environment and Phylogeny Between Herbaceous and Woody Angiosperm Species in China

2021 ◽  
Vol 12 ◽  
Author(s):  
Nannan An ◽  
Nan Lu ◽  
Bojie Fu ◽  
Mengyu Wang ◽  
Nianpeng He
Keyword(s):  
Leaf Area ◽  
Woody Species ◽  
Leaf Traits ◽  
Mean Annual Precipitation ◽  
Mean Annual Temperature ◽  
Dry Matter Content ◽  
Trait Variation ◽  
Leaf Trait ◽  
Environment Variables ◽  
Angiosperm Species

Leaf traits play key roles in plant resource acquisition and ecosystem processes; however, whether the effects of environment and phylogeny on leaf traits differ between herbaceous and woody species remains unclear. To address this, in this study, we collected data for five key leaf traits from 1,819 angiosperm species across 530 sites in China. The leaf traits included specific leaf area, leaf dry matter content, leaf area, leaf N concentration, and leaf P concentration, all of which are closely related to trade-offs between resource uptake and leaf construction. We quantified the relative contributions of environment variables and phylogeny to leaf trait variation for all species, as well as for herbaceous and woody species separately. We found that environmental factors explained most of the variation (44.4–65.5%) in leaf traits (compared with 3.9–23.3% for phylogeny). Climate variability and seasonality variables, in particular, mean temperature of the warmest and coldest seasons of a year (MTWM/MTWQ and MTCM/MTCQ) and mean precipitation in the wettest and driest seasons of a year (MPWM/MPWQ and MPDM/MPDQ), were more important drivers of leaf trait variation than mean annual temperature (MAT) and mean annual precipitation (MAP). Furthermore, the responses of leaf traits to environment variables and phylogeny differed between herbaceous and woody species. Our study demonstrated the different effects of environment variables and phylogeny on leaf traits among different plant growth forms, which is expected to advance the understanding of plant adaptive strategies and trait evolution under different environmental conditions.

Seasonal variation in foliar properties in Mediterranean Pine forests of different post-fire age

2021 ◽  
Author(s):  
Christodoulos I Sazeides ◽  
Nikolaos M Fyllas ◽  
Anastasia Christopoulou
Keyword(s):  
Leaf Area ◽  
Intraspecific Variation ◽  
Light Response ◽  
Leaf Traits ◽  
Seasonal Patterns ◽  
Dry Matter Content ◽  
Sapwood Area ◽  
Pinus Brutia ◽  
Foliar Traits ◽  
Trait Variability

<p>Foliar properties play a crucial role in local and global biochemical cycles. Systematic variation in key leaf traits has been reported both between and within species. Intraspecific variation in leaf traits is controlled by micro-environmental conditions and follows seasonal patterns. In this study we examine the seasonal patterns of six foliar traits including leaf area (LA), leaf thickness (Lth), leaf mass per area (LMA), leaf dry matter content (LDMC), leaf area to sapwood area ratio (LA/SA) and branch wood density (WD) in addition to the associated parameters of the Michaelis-Menten light response curve (i.e. light saturated net photosynthetic rate (Asat), half saturation coefficient (Km) and dark respiration rate (Rd)). We measured on a monthly basis the foliar traits and developed light response curves in four Pinus brutia dominated stands along a post-fire chronosequence (15, 40, 70 and 90 years) from sunlit branches. Significant differences in the interannual trait variability were found between stands for LDMC, WD and Asat, with the highest variability identified in the younger plot. LA/SA, Rd and Km also showed strong interannual variability although not statistically different between plots. A mixed effect model analysis revealed high intraclass correlation coefficients for Km and Asat suggesting that net photosynthesis is following systematic seasonal patterns. Overall LA was higher and LDMC was lower in the oldest plot and WD was higher in the denser (40 years) plot. Interestingly gas exchange parameters did not show differences in their overall mean values. Across plots, Asat was strongly positively related to Km, and LMA was positively related to LDMC and Lth. LDMC was also positively related with Asat and negatively with Lth. A principal component analysis (PCA) revealed two major dimensions of intraspecific trait variability within our plots. The first PCA axis was positively related to Asat, Km, LDMC and LMA suggesting that regardless of the stand age needles are placed along a fast-slow carbon gain dimension with denser needles illustrating faster area-based photosynthesis. The second PCA axis was positively related to LA and Lth suggesting that bigger needles are also thicker. A subsequent permutational multivariate analysis of variance revealed that the centroids and the dispersion of the trait syndromes differed between stands, with the youngest plot illustrating higher trait dispersion and the oldest plot characterized by bigger and thicker needles. Thus, in older stands were competition for light is higher, needles are deployed to be bigger and thicker to optimize light capture, while in younger stands they are optimized along a leaf density - photosynthetic capacity spectrum depending on (more heterogeneous) microenvironmental conditions. Our findings illustrate that intraspecific variation can be attributed to either seasonal (abiotic) light availability or to (biotic) heterogeneity related to stand structure, and have important implications for local scale forest dynamics models.</p><p>«This research is co-financed by Greece and the European Union (European Social Fund- ESF) through the Operational Programme «Human Resources Development, Education and Lifelong Learning 2014-2020» in the context of the project “Carbon fluxes across a post-fire chronosequence in Pinus brutia Ten forests.” (MIS 5049513)».</p>

scholarly journals Article Variation and Tradeoff of Leaf Traits of Karst Shrub in Southwest China

2020 ◽  
Author(s):  
zhigang zou ◽  
Fuping Zeng ◽  
Zhaoxia Zeng ◽  
Jianxiong Liao ◽  
Hu Du ◽  
...  
Keyword(s):  
Leaf Area ◽  
Southwest China ◽  
Scientific Information ◽  
Leaf Traits ◽  
Karst Region ◽  
Research Station ◽  
Dry Matter Content ◽  
Leaf Trait ◽  
Environmental Selection ◽  
Trade Offs

Abstract Long-term droughts were found to have guided the environmental selection ofshrub plant characteristics in a karst region of China, as the plants were found to have developed a set of leaf trait combinations,includinga small specific leaf area (SLA), leaf area (LA), and large leaf dry matter content (LDMC), that are known to be suitable for drought environments.Leaf traits of plants are not only the intuitive and operable taxonomic traits in plant taxonomy, but also reflect the responses and adaptations of plants to their habitats. This is helpful when trying to understand the role of environmental screening and when filtering plant functional traits. The objective of this investigation was to determine the leaf trait variations, adaptations, and patterns in the shrubs from a karst region in China.Weinvestigated 11 leaf traits to quantify the variations in their trade-offs and the trait–habitat /species relationships for the shrubs at theHuanjiang karst ecosystem observation and research station, China, using multivariate analyses.There were significant intraspecific and interspecific changes in the leaf traits ofthe shrub plants, and there were differences among the traits. Except for carbonmass, nitrogenarea, and phosphorousarea, the interspecific variations of the leaf traits were generally higher than the interspecific variation. The correlation between the leaf traits in the karst shrubs was also significant. Species differences had a higher explanatory degree for the leaf traits than topography or soil nutrients. The findings of this study will enhance our understanding of the variations in leaf traits in the karst shrubregions and the adaptative strategies of the plants in degraded habitats.Furthermore, these results may provide scientific information to help guide vegetation recovery programs in the karst region of southwest China.

scholarly journals Effects of grazing on leaf traits and ecosystem functioning in Inner Mongolia grasslands: scaling from species to community

2009 ◽  
Vol 6 (5) ◽  
pp. 9945-9975 ◽  
Author(s):  
S. X. Zheng ◽  
H. Y. Ren ◽  
Z. C. Lan ◽  
W. H. Li ◽  
Y. F. Bai
Keyword(s):  
Leaf Area ◽  
River Basin ◽  
Ecosystem Functioning ◽  
Leaf Traits ◽  
Northern China ◽  
Leaf Biomass ◽  
Area Index ◽  
Semiarid Grassland ◽  
Leaf Trait ◽  
Leaf Mass

Abstract. More attention has focused on using some easily measured plant functional traits to predict grazing influence on plant growth and ecosystem functioning. However, there has been much controversy on leaf traits response to grazing, thus more research should be conducted at the species level. Here we investigated the leaf area, leaf mass and specific leaf area (SLA) of 263 species in eight grassland communities along a soil moisture gradient in the Xilin River Basin, a semiarid grassland of northern China, to explore the grazing effects on ecosystem functioning. Results demonstrated that grazing decreased the leaf area and leaf mass in more than 56% of species in the Xilin River Basin, however, responses of SLA to grazing varied widely between species. Grazing increased SLA in 38.4% of species, decreased SLA in 31.3% of species and had no effect on 30.3% of species. Annuals and biennials generally developed high SLA as grazing tolerance traits, while perennial graminoids developed low SLA as grazing avoidance traits. Considering the water ecotypes, the SLA-increased and SLA-unchanged species were dominated by hygrophytes and mesophytes, while the SLA-decreased species were dominated by xerophytes. At the community level, grazing decreased the mean leaf area index (LAI) of six communities by 16.9%, leaf biomass by 35.2% and standing aboveground biomass (SAB) by 35.0% in the Xilin River Basin, indicating that overgrazing greatly decreased the ecosystem functioning in the semi-arid grassland of northern China. Soil properties, especially fielding holding capacity and soil organic carbon and total nitrogen could mediate the negative grazing impacts. The results suggest SLA is a better leaf trait to reveal plant adaptability to grazing. Our findings have practical implications for range management and productivity maintenance in the semiarid grassland, and it is feasible to take some measures such as ameliorating soil water and nutrient availabilities to prevent grassland degradation.

scholarly journals Analysis of Cultivar-Specific Variability in Size-Related Leaf Traits and Modeling of Single Leaf Area in Three Medicinal and Aromatic Plants: Ocimum basilicum L., Mentha Spp., and Salvia Spp.

Plants ◽  
2019 ◽  
Vol 9 (1) ◽  
pp. 13
Author(s):  
Maurizio Teobaldelli ◽  
Boris Basile ◽  
Francesco Giuffrida ◽  
Daniela Romano ◽  
Stefania Toscano ◽  
...  
Keyword(s):  
Leaf Area ◽  
Leaf Size ◽  
Leaf Traits ◽  
Ocimum Basilicum ◽  
Leaf Length ◽  
Measured Parameter ◽  
Aromatic Plants ◽  
Medicinal And Aromatic Plants ◽  
Single Leaf ◽  
Best Fitting

In this study, five allometric models were used to estimate the single leaf area of three well-known medicinal and aromatic plants (MAPs) species, namely basil (Ocimum basilicum L.), mint (Mentha spp.), and sage (Salvia spp.). MAPs world production is expected to rise up to 5 trillion US$ by 2050 and, therefore, there is a high interest in developing research related to this horticultural sector. Calibration of the models was obtained separately for three selected species by analyzing (a) the cultivar variability—i.e., 5 cultivars of basil (1094 leaves), 4 of mint (901 leaves), and 5 of sage (1103 leaves)—in the main two traits related to leaf size (leaf length, L, and leaf width, W) and (b) the relationship between these traits and single leaf area (LA). Validation of the chosen models was obtained for each species using an independent dataset, i.e., 487, 441, and 418 leaves, respectively, for basil (cv. ‘Lettuce Leaf’), mint (cv. ‘Comune’), and sage (cv. ‘Comune’). Model calibration based on fast-track methodologies, such as those using one measured parameter (one-regressor models: L, W, L2, and W2) or on more accurate two-regressors models (L × W), allowed to achieve different levels of accuracy. This approach highlighted the importance of considering intra-specific variability before applying any models to a certain cultivar to predict single LA. Eventually, during the validation phase, although modeling of single LA based on W2 showed a good fitting (R2basil = 0.948; R2mint = 0.963; R2sage = 0.925), the distribution of the residuals was always unsatisfactory. On the other hand, two-regressor models (based on the product L × W) provided the best fitting and accuracy for basil (R2 = 0.992; RMSE = 0.327 cm2), mint (R2 = 0.998; RMSE = 0.222 cm2), and sage (R2 = 0.998; RMSE = 0.426 cm2).

scholarly journals Soil water deficit decreases xylem conductance efficiency relative to leaf area and mass in the apple

2014 ◽  
Vol 1 ◽  
pp. e003 ◽  
Author(s):  
Pierre-Éric Lauri ◽  
Antoine Marceron ◽  
Frédéric Normand ◽  
Anaëlle Dambreville ◽  
Jean-Luc Regnard
Keyword(s):  
Leaf Area ◽  
Leaf Size ◽  
Dry Mass ◽  
Hydraulic Conductance ◽  
Hydraulic Efficiency ◽  
Leaf Lamina ◽  
Linear Relationships ◽  
Leaf Dry Mass ◽  
Extended Range ◽  
The Individual

It is generally postulated that at the tree scale a drought-related decrease in hydraulic conductance is balanced by a decrease of leaf area. We hypothesized that, at the individual leaf scale, drought affects the allometry between leaf area or mass and hydraulics, leading to a non-linear relationships between these traits. The study was conducted on well-watered and on water-stressed shoots of several apple genotypes covering an extended range of leaf area. Working on dried leaves, we measured leaf lamina area and mass and analyzed their relationships with the maximal xylem hydraulic conductance of the water pathway through the parent shoot and the petiole connected to the leaf lamina. Drought decreased leaf area and mass in absolute values. It also changes the allometric relationships between these two variables: for a same decrease of leaf dry mass the water-stressed shoot had a lower decrease of leaf dry area than the well-watered shoot. Our study also showed that drought affected the stem-to-petiole hydraulics with a higher hydraulic efficiency in the well-watered shoot compared to the water-stressed shoot. We discuss that, compared to the well-watered condition, drought not only decreased leaf size, but also reduced xylem efficiency through the stem-to-petiole pathway with regard to the leaf area and mass supplied.

scholarly journals Morphology of Two-year-old Limb Sections and Mid-season Spur Quality of Four Apple Cultivars on Five Dwarfing Rootstocks

HortScience ◽  
1997 ◽  
Vol 32 (3) ◽  
pp. 506D-506
Author(s):  
W. Alan Erb ◽  
David C. Ferree ◽  
Frank D. Morrison ◽  
Mark Pyeatt ◽  
Richard Ryer
Keyword(s):  
Leaf Area ◽  
Leaf Size ◽  
Stem Length ◽  
Stem Density ◽  
Sectional Area ◽  
Cross Sectional ◽  
Long Shoots ◽  
Apple Cultivars ◽  
Short Shoots

This study was conducted at three locations (Manhattan, Kan.; Wichita, Kan.; Wooster, Ohio) for 3 years (1994–1996). At bloom, 2-year-old limb sections from `Smoothee', `Jonagold', `Empire', and `Rome' on M.9EMLA, Bud 9, Mark, Ottawa 3, or M.26EMLA were evaluated for flowering and vegetative, spurs (5 cm or less), short shoots (5–15 cm) and long shoots (>15 cm). In mid-August, spur quality was estimated by randomly selecting five spurs per cultivar rootstock combination. There were significant location and year differences for all the morphological and spur quality characters measured. Across locations and years, the following characteristics were consistently high for the cultivars listed: stem density of flowering spurs for `Empire'; and leaf area, bud-diameter and average leaf size per spur for `Jonagold'. The most consistently high characteristics across locations and years for the rootstocks were for stem density of flowering spurs for Mark and leaf number, leaf area, bud-diameter, and average leaf size per spur for M.26EMLA. Stem density for flowering short shoots was highest for `Smoothee' and M.9EMLA in Wooster, `Jonagold' and Bud 9 in Wichita and `Rome', `Jonagold', and Bud 9 in Manhattan. Flowering long shoot stem density was highest for `Smoothee', `Jonagold', and M.26EMLA in Wooster, `Smoothee' in Wichita, and `Jonagold' and Ottawa 3 in Manhattan. There were some significant cultivar by rootstock interactions. The most-consistent interactions across locations and years were for stem cross-sectional area, stem length, stem density of flowering spurs, and flowering short shoots and bud-diameter per spur.

Oviposition of a leaf-miner on Erythroxylum tortuosum (Erythroxylaceae) leaves: hierarchical variation of physical leaf traits

2012 ◽  
Vol 60 (2) ◽  
pp. 136 ◽  
Author(s):  
P. R. De Sibio ◽  
M. N. Rossi
Keyword(s):  
Leaf Area ◽  
Spatial Resolution ◽  
Fluctuating Asymmetry ◽  
Oviposition Preference ◽  
Leaf Size ◽  
Preference Test ◽  
Leaf Traits ◽  
Leaf Miner ◽  
Leaf Miners ◽  
Resolution Level

Plants do not offer homogeneous supplies of the resources required by herbivorous insects as many resource traits show considerable variation both within and between plants. The distribution of variation among host-plant attributes determines the optimal spatial resolution level for insect females to select the best resource patches for oviposition. In this study, we examine whether variation in fluctuating asymmetry and size of Erythroxylum tortuosum Mart. (Erythroxylaceae) leaves influence oviposition of the specialist leaf-miner Agnippe Chambers (Lepidoptera: Gelechiidae). By partitioning the variance across five hierarchical levels, the oviposition pattern was investigated at the spatial resolution level where these leaf traits varied the most. We confirm that the largest variation in both these leaf attributes occurs at the leaf level. We hypothesise that leaf-miner females will respond to this variation by selecting the best leaves (resources) on which to lay their eggs. We find that the probability of oviposition is not significantly related to fluctuating asymmetry or to leaf size (oviposition preference test), suggesting that these two physical traits are not relevant to leaf-miners as indicators of resource patch quality. Therefore, although we show that females laid significantly more eggs on larger leaves, this behaviour appears not to be a result of active selection of leaves. Our results suggest that Agnippe females probably adjust their oviposition proportionally to leaf area because the relationship between egg density and leaf area was not statistically significant.

scholarly journals Leaf trait variability between and within subalpine grassland species differs depending on site conditions and herbivory

2019 ◽  
Vol 286 (1907) ◽  
pp. 20190429 ◽  
Author(s):  
Jennifer Firn ◽  
Huong Nguyen ◽  
Martin Schütz ◽  
Anita C. Risch
Keyword(s):  
Plant Traits ◽  
Intraspecific Variability ◽  
Leaf Traits ◽  
Nutrient Concentrations ◽  
Phosphorus Concentration ◽  
Geographical Differences ◽  
Leaf Trait ◽  
Interspecific Variability ◽  
Herbivore Exclusion ◽  
Trait Variability

Plant traits are commonly used to predict ecosystem-level processes, but the validity of such predictions is dependent on the assumption that trait variability between species is greater than trait variability within a species—the robustness assumption. Here, we compare leaf trait intraspecific and interspecific variability depending on geographical differences between sites and 5 years of experimental herbivore exclusion in two vegetation types of subalpine grasslands in Switzerland. Four leaf traits were measured from eight herbaceous species common to all 18 sites. Intraspecific trait variability differed significantly depending on site and herbivory. However, the amount and structure of variability depended on the trait measured and whether considering leaf traits separately or multiple leaf traits simultaneously. Leaf phosphorus concentration showed the highest intraspecific variability, while specific leaf area showed the highest interspecific variability and displayed intraspecific variability only in response to herbivore exclusion. Species identity based on multiple traits was not predictable. We find intraspecific variability is an essential consideration when using plant functional traits as a common currency not just species mean traits. This is particularly true for leaf nutrient concentrations, which showed high intraspecific variability in response to site differences and herbivore exclusion, a finding which suggests that the robustness assumption does not always hold.

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