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Author Schimann, H.; Vleminckx, J.; Baraloto, C.; Engel, J.; Jaouen, G.; Louisanna, E.; Manzi, S.; Sagne, A.; Roy, M.
Title Tree communities and soil properties influence fungal community assembly in neotropical forests Type Journal Article
Year 2020 Publication Biotropica Abbreviated Journal Biotropica
Volume 52 Issue (down) 3 Pages 444-456
Keywords communities; composition; diversity; habitat; lowland neotropical rain forest; macrofungi; soil properties; trees; ectomycorrhiza; fungus; heterogeneity; Neotropical Region; physicochemical property; rainforest; species inventory; species richness; tree; tropical forest; French Guiana; Agaricales; Aphyllophorales; Basidiomycota
Abstract The influence exerted by tree communities, topography, and soil chemistry on the assembly of macrofungal communities remains poorly understood, especially in highly diverse tropical forests. Here, we used a large dataset that combines inventories of macrofungal Basidiomycetes fruiting bodies, tree species composition, and measurements for 16 soil physicochemical parameters, collected in 34 plots located in four sites of lowland rain forests in French Guiana. Plots were established on three different topographical conditions: hilltop, slope, and seasonally flooded soils. We found hyperdiverse Basidiomycetes communities, mainly comprising members of Agaricales and Polyporales. Phosphorus, clay contents, and base saturation in soils strongly varied across plots and shaped the richness and composition of tree communities. The latter composition explained 23% of the variation in the composition of macrofungal communities, probably through high heterogeneity of the litter chemistry and selective effects of biotic interactions. The high local heterogeneity of habitats influenced the distribution of both macrofungi and trees, as a result of diversed local soil hydromorphic conditions associated with contrasting soil chemistry. This first regional study across habitats of French Guiana forests revealed new niches for macrofungi, such as ectomycorrhizal ones, and illustrates how macrofungi inventories are still paramount to can be to understand the processes at work in the tropics. Abstract in Spanish is available with online material. © 2020 The Association for Tropical Biology and Conservation
Address Laboratoire Évolution et Diversité Biologique, CNRS, UMR 5174 UPS CNRS ENFA IRD, Université Toulouse 3 Paul Sabatier, Toulouse, France
Corporate Author Thesis
Publisher Blackwell Publishing Ltd Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 00063606 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 968
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Author Vleminckx, J.; Bauman, D.; Demanet, M.; Hardy, O.J.; Doucet, J.-L.; Drouet, T.
Title Past human disturbances and soil fertility both influence the distribution of light-demanding tree species in a Central African tropical forest Type Journal Article
Year 2020 Publication Journal of Vegetation Science Abbreviated Journal J. Veg. Sci.
Volume 31 Issue (down) 3 Pages 440-453
Keywords light-demanding species; moist tropical forests; past human disturbances; shade-bearer species; soil charcoal abundance; soil properties; tree community assemblages; wood-specific gravity; anthropogenic effect; forest canopy; forest ecosystem; shifting cultivation; soil fertility; soil property; tree; tropical forest; Cameroon
Abstract Questions: In vast areas of Central African forests, the upper canopy is presently dominated by light-demanding tree species. Here, we confront three hypotheses to explain this dominance: (a) these species have expanded their distribution because of widespread past slash-and-burn activities, as suggested by important charcoal amounts recorded in the soils of the region; (b) their abundance is rather explained by soil properties, as this guild establishes preferentially on favourable physico-chemical conditions for rapid growth; (c) soil properties have been substantially influenced by past human disturbances and those two effects cannot be disentangled. Location: Pallisco-CIFM logging concession, southeastern Cameroon (300,000 ha). Methods: We quantified soil charcoal abundance and measured ten soil variables at the basis of 60 target trees that belonged to a list of three long-living pioneer light-demanding (LLP) and four shade-bearer (SB) species. We identified all stems with a diameter at breast height (DBH) ≥ 20 cm within a distance of 15 m around each target tree. Species were characterised by their wood-specific gravity (WSG), which reflected their light requirement. Multiple regression models were used to quantify and test the relative effects of charcoal abundance and soil variables on the mean WSG of the 60 tree communities, as well as the abundance of three guilds: LLP, SB, and non-pioneer light demanders (NPLD). Results: The mean WSG was the only response variable significantly explained by soil variables and charcoal abundance combined. It was significantly negatively associated with soil calcium and Mg content and with charcoal abundance, with soil and charcoal influencing the mean WSG independently. Conclusion: Our study provides evidence that past human disturbances and soil fertility have independently promoted the establishment of light-demanding species in western Central African forests, thereby shedding light on tree community assembly rules in these ecosystems which remain considerably understudied compared to the tropical forests of other continents. © 2020 International Association for Vegetation Science
Address Forest is life, TERRA Teaching and Research Centre, Université de Liège – Gembloux Agro-Bio Tech, Gembloux, Belgium
Corporate Author Thesis
Publisher Wiley-Blackwell Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 11009233 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 970
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Author Soong, J.L.; Janssens, I.A.; Grau, O.; Margalef, O.; Stahl, C.; Van Langenhove, L.; Urbina, I.; Chave, J.; Dourdain, A.; Ferry, B.; Freycon, V.; Herault, B.; Sardans, J.; Peñuelas, J.; Verbruggen, E.
Title Soil properties explain tree growth and mortality, but not biomass, across phosphorus-depleted tropical forests Type Journal Article
Year 2020 Publication Scientific reports Abbreviated Journal Sci Rep
Volume 10 Issue (down) 2302 Pages
Keywords
Abstract We observed strong positive relationships between soil properties and forest dynamics of growth and mortality across twelve primary lowland tropical forests in a phosphorus-poor region of the Guiana Shield. Average tree growth (diameter at breast height) increased from 0.81 to 2.1 mm yr-1 along a soil texture gradient from 0 to 67% clay, and increasing metal-oxide content. Soil organic carbon stocks in the top 30 cm ranged from 30 to 118 tons C ha-1, phosphorus content ranged from 7 to 600 mg kg-1 soil, and the relative abundance of arbuscular mycorrhizal fungi ranged from 0 to 50%, all positively correlating with soil clay, and iron and aluminum oxide and hydroxide content. In contrast, already low extractable phosphorus (Bray P) content decreased from 4.4 to <0.02 mg kg-1 in soil with increasing clay content. A greater prevalence of arbuscular mycorrhizal fungi in more clayey forests that had higher tree growth and mortality, but not biomass, indicates that despite the greater investment in nutrient uptake required, soils with higher clay content may actually serve to sustain high tree growth in tropical forests by avoiding phosphorus losses from the ecosystem. Our study demonstrates how variation in soil properties that retain carbon and nutrients can help to explain variation in tropical forest growth and mortality, but not biomass, by requiring niche specialization and contributing to biogeochemical diversification across this region.
Address Institut National Polytechnique Félix Houphouët-Boigny, Ivory CoastYamoussoukro, Cote d'Ivoire
Corporate Author Thesis
Publisher NLM (Medline) Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 20452322 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 916
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Author Levionnois, S.; Coste, S.; Nicolini, E.; Stahl, C.; Morel, H.; Heuret, P.
Title Scaling of petiole anatomies, mechanics and vasculatures with leaf size in the widespread Neotropical pioneer tree species Cecropia obtusa Trécul (Urticaceae) Type Journal Article
Year 2020 Publication Tree physiology Abbreviated Journal Tree Physiol.
Volume 40 Issue (down) 2 Pages 245-258
Keywords allometry; leaf size; petiole anatomy; scaling; theoretical hydraulic conductivity; vessel widening; xylem
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. © The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please email: journals.permission@oup.com.
Address UMR AMAP, CIRAD, CNRS, IRD, Université de Montpellier, Montpellier, 34398, France
Corporate Author Thesis
Publisher NLM (Medline) Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 17584469 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 16 March 2020 Approved no
Call Number EcoFoG @ webmaster @ Serial 921
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Author Ntawuhiganayo, E.B.; Uwizeye, F.K.; Zibera, E.; Dusenge, M.E.; Ziegler, C.; Ntirugulirwa, B.; Nsabimana, D.; Wallin, G.; Uddling, J.
Title Traits controlling shade tolerance in tropical montane trees Type Journal Article
Year 2020 Publication Tree physiology Abbreviated Journal Tree Physiol.
Volume 40 Issue (down) 2 Pages 183-197
Keywords biomass allocation; leaf temperature; plant traits; Rwanda; shade intolerance; shade tolerance; tropical montane forest; article; biomass allocation; breathing; canopy; carbon balance; compensation; photosynthesis; plant leaf; plant stem; rain forest; Rwanda; shade tolerance; species difference; sweating
Abstract Tropical canopies are complex, with multiple canopy layers and pronounced gap dynamics contributing to their high species diversity and productivity. An important reason for this complexity is the large variation in shade tolerance among different tree species. At present, we lack a clear understanding of which plant traits control this variation, e.g., regarding the relative contributions of whole-plant versus leaf traits or structural versus physiological traits. We investigated a broad range of traits in six tropical montane rainforest tree species with different degrees of shade tolerance, grown under three different radiation regimes (under the open sky or beneath sparse or dense canopies). The two distinct shade-tolerant species had higher fractional biomass in leaves and branches while shade-intolerant species invested more into stems, and these differences were greater under low radiation. Leaf respiration and photosynthetic light compensation point did not vary with species shade tolerance, regardless of radiation regime. Leaf temperatures in open plots were markedly higher in shade-tolerant species due to their low transpiration rates and large leaf sizes. Our results suggest that interspecific variation in shade tolerance of tropical montane trees is controlled by species differences in whole-plant biomass allocation strategy rather than by difference in physiological leaf traits determining leaf carbon balance at low radiation. © The Author(s) 2019. Published by Oxford University Press.
Address Rwanda Agriculture and Animal Resources Development, PO Box 5016Kigali, Rwanda
Corporate Author Thesis
Publisher NLM (Medline) Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 17584469 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 16 March 2020 Approved no
Call Number EcoFoG @ webmaster @ Serial 922
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Author Privet, K.; Vedel, V.; Fortunel, C.; Orivel, J.; Martinez, Q.; Cerdan, A.; Baraloto, C.; Pétillon, J.
Title Relative effciency of pitfall trapping vs. nocturnal hand collecting in assessing soil-dwelling spider diversity along a structural gradient of neotropical habitats Type Journal Article
Year 2020 Publication Diversity Abbreviated Journal Diversity
Volume 12 Issue (down) 2 Pages 81
Keywords Araneae; Diversity indices; Functional diversity; Guiana shield; Sampling methods; Species richness; Turnover; Araneae
Abstract Assessing spider diversity remains a great challenge, especially in tropical habitats where dozens of species can locally co-occur. Pitfall trapping is one of the most widely used techniques to collect spiders, but it suffers from several biases, and its accuracy likely varies with habitat complexity. In this study, we compared the efficiency of passive pitfall trapping versus active nocturnal hand collecting (\"HC) to capture low understory-dwelling spider taxonomical (morpho-species) and functional (hunting guilds) diversity along a structural gradient of habitats in French Guiana. We focused on four habitats describing a structural gradient: garden to the orchard to the forest edge to the undisturbed forest. Overall, estimated morpho-species richness and composition did not vary consistently between habitats, but abundances of ground-hunting spiders decreased significantly with increasing habitat complexity. We found habitat-dependence differences in taxonomic diversity between sampling strategies: NHC revealed higher diversity in the orchard, whereas pitfalls resulted in higher diversity in the forest. Species turnover resulted in high dissimilarity in species composition between habitats using either method. This study shows how pitfall trapping is influenced by habitat structure, rendering this sampling method incomplete for complex, tropical environments. However, pitfall traps remain a valuable component of inventories because they sample distinct assemblage of spiders. © 2020 by the authors.
Address International Center for Tropical Botany, Department of Biological Sciences, Florida International University, 11200 S.W. 8th Street, Miami, FL 33199, United States
Corporate Author Thesis
Publisher Mdpi Ag Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 14242818 (Issn) ISBN Medium
Area Expedition Conference
Notes Export Date: 16 March 2020; Correspondence Address: Privet, K.; CNRS, Ecobio (Ecosystèmes, biodiversité, évolution), Université de RennesFrance; email: kprivet@hotmail.fr Approved no
Call Number EcoFoG @ webmaster @ Serial 923
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Author Levionnois, S.; Ziegler, C.; Jansen, S.; Calvet, E.; Coste, S.; Stahl, C.; Salmon, C.; Delzon, S.; Guichard, C.; Heuret, P.
Title Vulnerability and hydraulic segmentations at the stem–leaf transition: coordination across Neotropical trees Type Journal Article
Year 2020 Publication New Phytologist Abbreviated Journal New Phytol.
Volume 228 Issue (down) 2 Pages 512-524
Keywords drought-induced embolism resistance; hydraulic segmentation; leaf-specific conductivity; stem–leaf transition; tropical trees; vulnerability segmentation; air bubble; hydraulic conductivity; leaf; Neotropical Region; rainforest; tropical forest; vulnerability; xylem
Abstract Hydraulic segmentation at the stem–leaf transition predicts higher hydraulic resistance in leaves than in stems. Vulnerability segmentation, however, predicts lower embolism resistance in leaves. Both mechanisms should theoretically favour runaway embolism in leaves to preserve expensive organs such as stems, and should be tested for any potential coordination. We investigated the theoretical leaf-specific conductivity based on an anatomical approach to quantify the degree of hydraulic segmentation across 21 tropical rainforest tree species. Xylem resistance to embolism in stems (flow-centrifugation technique) and leaves (optical visualization method) was quantified to assess vulnerability segmentation. We found a pervasive hydraulic segmentation across species, but with a strong variability in the degree of segmentation. Despite a clear continuum in the degree of vulnerability segmentation, eight species showed a positive vulnerability segmentation (leaves less resistant to embolism than stems), whereas the remaining species studied exhibited a negative or no vulnerability segmentation. The degree of vulnerability segmentation was positively related to the degree of hydraulic segmentation, such that segmented species promote both mechanisms to hydraulically decouple leaf xylem from stem xylem. To what extent hydraulic and vulnerability segmentation determine drought resistance requires further integration of the leaf–stem transition at the whole-plant level, including both xylem and outer xylem tissue. © 2020 The Authors. New Phytologist © 2020 New Phytologist Trust
Address Univ. Bordeaux, INRAE, BIOGECO, Pessac, F-33615, France
Corporate Author Thesis
Publisher Blackwell Publishing Ltd Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028646x (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 952
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Author Van Langenhove, L.; Verryckt, L.T.; Bréchet, L.; Courtois, E.A.; Stahl, C.; Hofhansl, F.; Bauters, M.; Sardans, J.; Boeckx, P.; Fransen, E.; Peñuelas, J.; Janssens, I.A.
Title Atmospheric deposition of elements and its relevance for nutrient budgets of tropical forests Type Journal Article
Year 2020 Publication Biogeochemistry Abbreviated Journal Biogeochemistry
Volume 149 Issue (down) 2 Pages 175-193
Keywords Litterfall; Nitrogen; Nutrient cycling; Phosphorus; Potassium; Throughfall; atmospheric deposition; canopy exchange; field method; forest floor; leaching; litterfall; nutrient cycling; phosphorus; potassium; precipitation (climatology); rainforest; tropical forest; French Guiana
Abstract Atmospheric deposition is an important component of the nutrient cycles of terrestrial ecosystems, but field measurements are especially scarce in tropical regions. In this study we analysed 15 months of precipitation chemistry collected in an old growth tropical forest located in French Guiana. We measured nutrient inputs via bulk precipitation and throughfall and used the canopy budget model to estimate nutrient fluxes via canopy exchange and dry deposition. Based on this method we quantified net fluxes of macronutrients and compared their contribution to internal cycling rates via litterfall. Our results suggest that while atmospheric deposition of nitrogen was relatively high (13 kg ha−1 year−1), and mainly in organic forms, the N inputs via litterfall were an order of magnitude higher. In contrast to nitrogen, we found that atmospheric deposition of phosphorus (0.5 kg ha−1 year−1) supplied up to one third of the annual litterfall input to the forest floor. Most strikingly, combined annual inputs of potassium via atmospheric deposition (14 kg ha−1 year−1) and canopy leaching (22 kg ha−1 year−1) were three times larger than internal nutrient recycling via litterfall (11 kg ha−1 year−1). We conclude that atmospheric deposition of phosphorus and especially potassium may play an important role in sustaining the productivity of this old-growth tropical rainforest. © 2020, Springer Nature Switzerland AG.
Address StatUa Center for Statistics, University of Antwerp, Prinsstraat 13, Antwerp, 2000, Belgium
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 01682563 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 964
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Author Lang, G.; Marcon, E.; Puech, F.
Title Distance-based measures of spatial concentration: introducing a relative density function Type Journal Article
Year 2020 Publication Annals of Regional Science Abbreviated Journal Ann. Reg. Sci.
Volume 64 Issue (down) 2 Pages 243-265
Keywords Agglomeration; Aggregation; Economic geography; Point patterns; Spatial concentration; accuracy assessment; econometrics; economic activity; economic geography; industrial agglomeration; industrial location; location decision; spatial analysis; spatial distribution
Abstract For more than a decade, distance-based methods have been widely employed and constantly improved in spatial economics. These methods are a very useful tool for accurately evaluating the spatial distribution of economic activity. We introduce a new distance-based statistical measure for evaluating the spatial concentration of industries. The m function is the first relative density function to be proposed in economics. This tool supplements the typology of distance-based methods recently drawn up by Marcon and Puech (J Econ Geogr 3(4):409–428, 2003). By considering several simulated and real examples, we show the advantages and the limits of the m function for detecting spatial structures in economics. © 2019, Springer-Verlag GmbH Germany, part of Springer Nature.
Address RITM, Univ. Paris-Sud, Université Paris-Saclay and CREST, Sceaux, France
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 05701864 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 976
Permanent link to this record
 

 
Author Fortunel, C.; Stahl, C.; Heuret, P.; Nicolini, E.; Baraloto, C.
Title Disentangling the effects of environment and ontogeny on tree functional dimensions for congeneric species in tropical forests Type Journal Article
Year 2020 Publication New Phytologist Abbreviated Journal New Phytol.
Volume 226 Issue (down) 2 Pages 385-395
Keywords chemistry; developmental stage; habitats; Micropholis; morphology; physiology; plant traits; seasons; developmental stage; ecosystem function; forest ecosystem; habitat selection; habitat structure; nutrient availability; ontogeny; physiological response; soil water; taxonomy; tropical forest; Amazonia
Abstract Soil water and nutrient availability are key drivers of tree species distribution and forest ecosystem functioning, with strong species differences in water and nutrient use. Despite growing evidence for intraspecific trait differences, it remains unclear under which circumstances the effects of environmental gradients trump those of ontogeny and taxonomy on important functional dimensions related to resource use, particularly in tropical forests. Here, we explore how physiological, chemical, and morphological traits related to resource use vary between life stages in four species within the genus Micropholis that is widespread in lowland Amazonia. Specifically, we evaluate how environment, developmental stage, and taxonomy contribute to single-trait variation and multidimensional functional strategies. We find that environment, developmental stage, and taxonomy differentially contribute to functional dimensions. Habitats and seasons shape physiological and chemical traits related to water and nutrient use, whereas developmental stage and taxonomic identity impact morphological traits –especially those related to the leaf economics spectrum. Our findings suggest that combining environment, ontogeny, and taxonomy allows for a better understanding of important functional dimensions in tropical trees and highlights the need for integrating tree physiological and chemical traits with classically used morphological traits to improve predictions of tropical forests’ responses to environmental change. © 2019 The Authors New Phytologist © 2019 New Phytologist Trust
Address Department of Biological Sciences, Florida International University, Miami, FL 33133, United States
Corporate Author Thesis
Publisher Blackwell Publishing Ltd Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028646x (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 977
Permanent link to this record