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Geraldo Rogerio Faustini Cuzzuol - One of the best experts on this subject based on the ideXlab platform.
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stem and leaf functional traits allow successional classification in six Pioneer and non Pioneer tree Species in tropical moist broadleaved forests
Ecological Indicators, 2020Co-Authors: Bernardo Pretti Becacici Macieira, Giuliano Maselli Locosselli, Marcos Silveira Buckeridge, Henrik Hartmann, Geraldo Rogerio Faustini CuzzuolAbstract:Abstract More than half of the tropical forests are secondary forests that are undergoing a highly dynamic interplay of forest succession of uncertain outcome. Vegetation models can help predict forest trajectory but require simplifying the high biodiversity of these forests into a few distinct classes of functional or successional groups. The classification of tree Species by successional groups has traditionally relied on qualitative criteria such as life span, or on parameters that are difficult to measure on mature trees in the field, like photosynthetic activity, in particular in tropical forests. Hence, quantitative traits that can be easily measured in a number of Species may provide more accurate classification thresholds. The present study identifies quantitative anatomical and biochemical traits of leaf and stem of six Species that are useful for classification of successional groups in the Tropical Moist Broadleaved Forest (TMBF) of south-eastern Brazil. Consistent with assumed fast growth and high light requirements of Pioneers the investigated Pioneer Species presented higher stem glucose content (600%), larger vessel elements (162%), greater stomatal density (72%) and higher chloroplastic pigments concentrations (90%) than non-Pioneer Species. By contrast, non-Pioneers were characterized by larger mesophyll cells (70%) and higher cell wall polymers concentrations (65–100%) in leaf and stem. The biggest differences between Pioneer and non-Pioneer Species were observed in leaf blade thickness, followed by vessel lumen diameter, and stem lignin. We provide research laboratories a variety of different tools that they can use as a guideline to accurately assess the successional class of tree Species in the TMBF of south-eastern Brazil.
Xi Fang - One of the best experts on this subject based on the ideXlab platform.
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tree growth traits and social status affect the wood density of Pioneer Species in secondary subtropical forest
Ecology and Evolution, 2017Co-Authors: Lingxiu Chen, Wenhua Xiang, Pifeng Lei, Shengli Zhang, Shuai Ouyang, Xiangwen Deng, Xi FangAbstract:Wood density (WD) is not only an important parameter to estimate aboveground biomass but also an indicator of timber quality and plant adaptation strategies to stressful conditions (i.e., windthrow, pests, and pathogens). This study had three objectives: (1) to compare WD among seven subtropical tree Species; (2) to determine how tree growth traits may influence possible differences in WD between the Pioneer and shade-tolerant Species; and (3) to examine whether or not WD differs by tree social status (dominant vs. suppressed trees) within Species. To do this, 70 trees were destructively harvested. From each tree, disks at different stem heights were obtained and subjected to a method of stem analysis to measure whole tree level WD. The results showed that WD differed significantly among the seven Species (p < .001). Their average WD was 0.537 g/cm3, ranging from 0.409 g/cm3 for Choerospondias axillaris to 0.691 g/cm3 for Cyclobalanopsis glauca. The average WD of the four Pioneer Species (0.497 ± 0.13 g/cm3) was significantly lower (p < .01) than that of the three shade-tolerant Species (0.589 ± 0.12 g/cm3). The WD of the Pioneers had a significant positive correlation with their stem diameter at breast height (DBH), tree height (H), and tree age, but WD had a significant negative correlation with relative growth rate (RGR). In contrast, the WD of the shade-tolerant tree Species had no significant relationships with DBH, H, tree age, or RGR. The dominant trees of the Pioneer Species had a higher WD than the suppressed trees, whereas the shade-tolerant Species had a lower WD for dominant trees than the suppressed trees. However, the differences in WD between dominant and suppressed trees were not significant. Taken together, the results suggest that classifying Species into Pioneer and shade-tolerant groups to examine the effects of tree growth traits and social status could improve our understanding of intra- and interspecific variation in WD among subtropical tree Species.
Jean-christophe Domec - One of the best experts on this subject based on the ideXlab platform.
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Comparative hydraulic architecture of tropical tree Species representing a range of successional stages and wood density
Oecologia, 2011Co-Authors: Katherine A. Mcculloh, Frederick C. Meinzer, John S. Sperry, Barbara Lachenbruch, Steven L. Voelker, David R. Woodruff, Jean-christophe DomecAbstract:Plant hydraulic architecture (PHA) has been linked to water transport sufficiency, photosynthetic rates, growth form and attendant carbon allocation. Despite its influence on traits central to conferring an overall competitive advantage in a given environment, few studies have examined whether key aspects of PHA are indicative of successional stage, especially within mature individuals. While it is well established that wood density (WD) tends to be lower in early versus late successional tree Species, and that WD can influence other aspects of PHA, the interaction of WD, successional stage and the consequent implications for PHA have not been sufficiently explored. Here, we studied differences in PHA at the scales of wood anatomy to whole-tree hydraulic conductance in Species in early versus late successional Panamanian tropical forests. Although the trunk WD was indistinguishable between the successional groups, the branch WD was lower in the early successional Species. Across all Species, WD correlated negatively with vessel diameter and positively with vessel packing density. The ratio of branch:trunk vessel diameter, branch sap flux and whole-tree leaf-specific conductance scaled negatively with branch WD across Species. Pioneer Species showed greater sap flux in branches than in trunks and a greater leaf-specific hydraulic conductance, suggesting that Pioneer Species can move greater quantities of water at a given tension gradient. In combination with the greater water storage capacitance associated with lower WD, these results suggest these Pioneer Species can save on the carbon expenditure needed to build safer xylem and instead allow more carbon to be allocated to rapid growth.
William Gerardo Vargas - One of the best experts on this subject based on the ideXlab platform.
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A brief description of the vegetation, with special emphasis on the intermediate Pioneers of the dry forests of La Jagua, in the upper basin of the Magdalena River in Huila
2018Co-Authors: William Gerardo VargasAbstract:Information on the flora of the dry forests of southern Huila province was revised, with emphasis on intermediate Pioneer Species that can support processes of ecological restoration and conservation of biodiversity, these data were compared with those obtained in the field over the past 30 years. According to literature, 203 intermediate Pioneer Species distributed in 123 genera and 45 botanical families were identified for Huila, while for La Jagua field data recorded 155 Species grouped in 111 genera and 45 families among which Leguminosae, Rubiaceae, Euphorbiaceae, Malvaceae, Melastomataceae and Moraceae are the most important families. The main types of hedges in the landscape of La Jagua are described, with notes on major plant Species, conservation status and representative fauna. A list of 155 intermediate Pioneer Species is proposed, with the most important attributes for use in processes of conservation and ecological restoration of dry forests in the region. This type of Species is key in generating habitat, connectivity, resources for wildlife and production of resources such as firewood and wood for communities, within a model of landscape management tools.
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Una breve descripción de la vegetación, con especial énfasis en las pioneras intermedias de los bosques secos de la Jagua, en la cuenca alta del Rio Magdalena en el Huila
Colombia Forestal, 2015Co-Authors: William Gerardo VargasAbstract:Information on the flora of the dry forests of southern Huila province was revised, with emphasis on intermediate Pioneer Species that can support processes of ecological restoration and conservation of biodiversity, these data were compared with those obtained in the field over the past 30 years. According to literature, 203 intermediate Pioneer Species distributed in 123 genera and 45 botanical families were identified for Huila, while for La Jagua field data recorded 155 Species grouped in 111 genera and 45 families among which Leguminosae, Rubiaceae, Euphorbiaceae, Malvaceae, Melastomataceae and Moraceae are the most important families. The main types of hedges in the landscape of La Jagua are described, with notes on major plant Species, conservation status and representative fauna. A list of 155 intermediate Pioneer Species is proposed, with the most important attributes for use in processes of conservation and ecological restoration of dry forests in the region. This type of Species is key in generating habitat, connectivity, resources for wildlife and production of resources such as firewood and wood for communities, within a model of landscape management tools.
Brigitta Erschbamer - One of the best experts on this subject based on the ideXlab platform.
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Demography of the alpine Pioneer Species Saxifraga aizoides in different successional stages at the glacier fore- land of the Rotmoosferner (Obergurgl, Ötztal, Austria) Demographie der alpinen Pionierart Saxifraga aizoides in verschiedenen Sukzession
2015Co-Authors: Eckart Winkler, Silvia Marcante, Brigitta ErschbamerAbstract:The demography of the alpine Pioneer Species Saxifraga aizoides was investigated along a successional gradient at the Rotmoos glacier foreland (2,330–2,450 m a.s.l., Obergurgl, Otztal, Austria) from recently deglaciated areas to advanced successional stages. A basic hypothesis of our study was that fecundity might play an essential role for population growth rate on the youngest site and become of minor importance at advanced successional stages. A matrix modelling approach was performed to calculate the main demographic parameters on 6, 33, and 81 year old moraines. Our results partly confirmed the prediction of the larger role of fecundity on the youngest sites. Here, seedling mortality was lower compared to the older sites, and the reproductive success was significantly higher. All in all, Saxifraga aizoides mainly follows a “persistence strategy” from the beginning, characterized by the fact that large individuals did not undergo mortality at the recently deglaciated site. However, in the long term a population decline will occur due to plant age and changes of environmental conditions along the successional gradient.
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The role of spontaneous selfing in the Pioneer Species Saxifraga aizoides
Flora, 2007Co-Authors: Corinna Raffl, Silvia Marcante, Brigitta ErschbamerAbstract:A large variety of reproductive patterns is present among alpine plants to ensure the persistence of populations in such harsh environments. In the present study, the role of spontaneous selfing and its contribution to the actual reproductive success of an alpine Pioneer plant was investigated. The results showed that Saxifraga aizoides is clearly self-compatible. Open-pollinated flowers exhibited higher seed numbers per capsules than selfing flowers, albeit the difference was not significant. Although seed weight seemed to be independent from the kind of pollination, open-pollinated flowers had a significantly higher proportion of germinated seeds than selfed ones. Furthermore, the ability of fast germination found in S. aizoides enables the seeds to take advantage of all possible opportunities for germination. In summary, S. aizoides exhibits a successful recruitment strategy for an alpine Pioneer Species.