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Author Blanc, L.; Echard, M.; Herault, B.; Bonal, D.; Marcon, E.; Chave, J.; Baraloto, C.
Title Dynamics of aboveground carbon stocks in a selectively logged tropical forest Type Journal Article
Year 2009 Publication Ecological Applications Abbreviated Journal Ecol. Appl.
Volume 19 Issue 6 Pages 1397-1404
Keywords aboveground biomass; carbon sequestration; deforestation; French Guiana; global change; timber stand improvement; tropical forests
Abstract The expansion of selective logging in tropical forests may be an important source of global carbon emissions. However, the effects of logging practices on the carbon cycle have never been quantified over long periods of time. We followed the fate of more than 60 000 tropical trees over 23 years to assess changes in aboveground carbon stocks in 48 1.56-ha plots in French Guiana that represent a gradient of timber harvest intensities, with and without intensive timber stand improvement (TSI) treatments to stimulate timber tree growth. Conventional selective logging led to emissions equivalent to more than a third of aboveground carbon stocks in plots without TSI (85 Mg C/ha), while plots with TSI lost more than one-half of aboveground carbon stocks (142 Mg C/ha). Within 20 years of logging, plots without TSI sequestered aboveground carbon equivalent to more than 80% of aboveground carbon lost to logging (-70.7 Mg C/ha), and our simulations predicted an equilibrium aboveground carbon balance within 45 years of logging. In contrast, plots with intensive TSI are predicted to require more than 100 years to sequester aboveground carbon lost to emissions. These results indicate that in some tropical forests aboveground carbon storage can be recovered within half a century after conventional logging at moderate harvest intensities.
Address [Bonal, Damien; Baraloto, Christopher] INRA, UMR Ecol Forets Guyane, Kourou 97379, French Guiana, Email: chris.baraloto@ecofog.gf
Corporate Author Thesis
Publisher (up) ECOLOGICAL SOC AMER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1051-0761 ISBN Medium
Area Expedition Conference
Notes ISI:000269075200003 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 105
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Author Fortunel, C.; Garnier, E.; Joffre, R.; Kazakou, E.; Quested, H.; Grigulis, K.; Lavorel, S.; Ansquer, P.; Castro, H.; Cruz, P.; Dolezal, J.; Eriksson, O.; Freitas, H.; Golodets, C.; Jouany, C.; Kigel, J.; Kleyer, M.; Lehsten, V.; Leps, J.; Meier, T.; Pakeman, R.; Papadimitriou, M.; Papanastasis, V.P.; Quetier, F.; Robson, M.; Sternberg, M.; Theau, J.P.; Thebault, A.; Zarovali, M.
Title Leaf traits capture the effects of land use changes and climate on litter decomposability of grasslands across Europe Type Journal Article
Year 2009 Publication Ecology Abbreviated Journal Ecology
Volume 90 Issue 3 Pages 598-611
Keywords climate; community functional parameters; disturbance; leaf traits; litter decomposability; litter quality
Abstract Land use and climate changes induce shifts in plant functional diversity and community structure, thereby modifying ecosystem processes. This is particularly true for litter decomposition, an essential process in the biogeochemical cycles of carbon and nutrients. In this study, we asked whether changes in functional traits of living leaves in response to changes in land use and climate were related to rates of litter potential decomposition, hereafter denoted litter decomposability, across a range of 10 contrasting sites. To disentangle the different control factors on litter decomposition, we conducted a microcosm experiment to determine the decomposability under standard conditions of litters collected in herbaceous communities from Europe and Israel. We tested how environmental factors ( disturbance and climate) affected functional traits of living leaves and how these traits then modified litter quality and subsequent litter decomposability. Litter decomposability appeared proximately linked to initial litter quality, with particularly clear negative correlations with lignin-dependent indices ( litter lignin concentration, lignin : nitrogen ratio, and fiber component). Litter quality was directly related to community-weighted mean traits. Lignin-dependent indices of litter quality were positively correlated with community-weighted mean leaf dry matter content (LDMC), and negatively correlated with community-weighted mean leaf nitrogen concentration (LNC). Consequently, litter decomposability was correlated negatively with community-weighted mean LDMC, and positively with community-weighted mean LNC. Environmental factors ( disturbance and climate) influenced community-weighted mean traits. Plant communities experiencing less frequent or less intense disturbance exhibited higher community-weighted mean LDMC, and therefore higher litter lignin content and slower litter decomposability. LDMC therefore appears as a powerful marker of both changes in land use and of the pace of nutrient cycling across 10 contrasting sites.
Address [Fortunel, Claire; Garnier, Eric; Joffre, Richard; Kazakou, Elena] CNRS, UMR 5175, Ctr Ecol Fonct & Evolut, F-34293 Montpellier 5, France, Email: claire.fortunel@ecofog.gf
Corporate Author Thesis
Publisher (up) ECOLOGICAL SOC AMER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes ISI:000263776800003 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 121
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Author Baraloto, C.; Morneau, F.; Bonal, D.; Blanc, L.; Ferry, B.
Title Seasonal water stress tolerance and habitat associations within four neotropical tree genera Type Journal Article
Year 2007 Publication Ecology Abbreviated Journal Ecology
Volume 88 Issue 2 Pages 478-489
Keywords drought tolerance; French Guiana; photosynthetic capacity; phylogenetically independent contrast; relative growth rate; seasonally flooded forest; specific leaf area; torus translation method; tropical forest
Abstract We investigated the relationship between habitat association and physiological performance in four congeneric species pairs exhibiting contrasting distributions between seasonally flooded and terra firme habitats in lowland tropical rain forests of French Guiana, including Virola and Iryanthera ( Myristicaceae), Symphonia ( Clusiaceae), and Eperua (Caesalpiniaceae). We analyzed 10-year data sets of mapped and measured saplings ( stems >= 150 cm in height and < 10 cm diameter at breast height [dbh]) and trees ( stems >= 10 cm dbh) across 37.5 ha of permanent plots covering a 300-ha zone, within which seasonally flooded areas ( where the water table never descends below 1 m) have been mapped. Additionally, we tested the response of growth, survival, and leaf functional traits of these species to drought and flood stress in a controlled experiment. We tested for habitat preference using a modi. cation of the torus translation method. Strong contrasting associations of the species pairs of Iryanthera, Virola, and Symphonia were observed at the sapling stage, and these associations strengthened for the tree stage. Neither species of Eperua was significantly associated with flooded habitats at the sapling stage, but E. falcata was significantly and positively associated with flooded forests at the tree stage, and trees of E. grandiflora were found almost exclusively in nonflooded habitats. Differential performance provided limited explanatory support for the observed habitat associations, with only congeners of Iryanthera exhibiting divergent sapling survival and tree growth. Seedlings of species associated with flooded forest tended to have higher photosynthetic capacity than their congeners at field capacity. In addition, they tended to have the largest reductions in leaf gas exchange and growth rate in response to experimental drought stress and the least reductions in response to experimental inundation. The corroboration of habitat association with differences in functional traits and, to a lesser extent, measures of performance provides an explanation for the regional coexistence of these species pairs. We suggest that specialization to seasonally flooded habitats may explain patterns of adaptive radiation in many tropical tree genera and thereby provide a substantial contribution to regional tree diversity.
Address INRA, UMR Ecol Forets Guyane, Kourou, French Guiana, Email: baraloto@botany.ufl.edu
Corporate Author Thesis
Publisher (up) ECOLOGICAL SOC AMER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes ISI:000245668400021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 165
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Author Baraloto, C.; Goldberg, D.E.; Bonal, D.
Title Performance trade-offs among tropical tree seedlings in contrasting microhabitats Type Journal Article
Year 2005 Publication Ecology Abbreviated Journal Ecology
Volume 86 Issue 9 Pages 2461-2472
Keywords canopy gaps; French Guiana; regeneration niche; relative growth rate; seed size; shade tolerance; soil moisture; tropical forest
Abstract We investigated performance trade-offs among seedlings of nine tropical tree species during a -five-year field experiment. Seedlings were grown in eight microhabitat types composed of paired gap and shaded understory sites in each of four soil types. We defined performance trade-offs relevant to coexistence as significant pairwise rank reversals for species performance between contrasting situations, of which we characterize three types: microhabitat, fitness component, and ontogenetic. Only 2 of 36 species pairs exhibited microhabitat trade-offs or reversed rankings for survival or relative growth rate (RGR) among microhabitats, and only one species pair reversed performance ranks among soil types. We found stronger evidence for rank reversals between fitness components (survival and RGR), particularly in gap vs. understory environments, suggesting a general trade-off between shade tolerance (survival in shade) and gap establishment (RGR in gaps). Third, the most frequent rank reversals between species pairs occurred between early and later ontogenetic stages, especially between fitness components in contrasting microhabitats. Overall, 15 of 36 pairs of potentially competing species exhibited some type of seedling performance trade-off, two species pairs never outperformed one another, and for 19 species pairs one species was a consistent better performer. We suggest that ontogenetic trade-offs, in concert with microhabitat and fitness component trade-offs, may contribute to species coexistence of long-lived organisms such as tropical trees.
Address Univ Michigan, Dept Ecol & Evolutionary Biol, Ann Arbor, MI 48109 USA, Email: baraloto.c@kourou.cirad.fr
Corporate Author Thesis
Publisher (up) ECOLOGICAL SOC AMER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes ISI:000231373600021 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 252
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Author Lamarre, G.P.A.; Baraloto, C.; Fortunel, C.; Dávila, N.; Mesones, I.; Rios, J.G.; Ríos, M.; Valderrama, E.; Pilco, M.V.; Fine, P.V.A.
Title Herbivory, growth rates, and habitat specialization in tropical tree lineages: implications for Amazonian beta-diversity Type Journal Article
Year 2012 Publication Ecology Abbreviated Journal Ecology
Volume 93 Issue sp8 Pages S195-S210
Keywords
Abstract
Address
Corporate Author Thesis
Publisher (up) Ecological Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes doi: 10.1890/11-0397.1 Approved no
Call Number EcoFoG @ webmaster @ Serial 459
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Author Turcotte, M.M.; Thomsen, C.J.M.; Broadhead, G.T.; Fine, P.V.A.; Godfrey, R.M.; Lamarre, G.P.A.; Meyer, S.T.; Richards, L.A.; Johnson, M.T.J.
Title Percentage leaf herbivory across vascular plant species Type Journal Article
Year 2014 Publication Ecology Abbreviated Journal Ecology
Volume 95 Issue 3 Pages 788-788
Keywords
Abstract Herbivory is viewed as a major driver of plant evolution and the most important energy pathway from plants to higher trophic levels. Therefore, understanding patterns of herbivory on plants remains a key focus in evolution and ecology. The evolutionary impacts of leaf herbivory include altering plant fitness, local adaptation, the evolution of defenses, and the diversification of plants as well as natural enemies. Leaf herbivory also impacts ecological processes such as plant productivity, community composition, and ecosystem nutrient cycling. Understanding the impact of herbivory on these ecological and evolutionary processes requires species-specific, as opposed to community-level, measures of herbivory. In addition, species-specific data enables the use of modern comparative methods to account for phylogenetic non-independence. Although hundreds of studies have measured natural rates of leaf consumption, we are unaware of any accessible compilation of these data. We created such a data set to provide the raw data needed to test general hypotheses relating to plant?herbivore interactions and to test the influence of biotic and abiotic factors on herbivory rates across large spatial scales. A large repository will make this endeavor more efficient and robust. In total, we compiled 2641 population-level measures for either annual or daily rates of leaf herbivory across 1145 species of vascular plants collected from 189 studies. All damage measures represent natural occurrences of herbivory that span numerous angiosperm, gymnosperm, and fern species. To enable researchers to explore the causes of variation in herbivory and how these might interact, we added information about the study sites including: geolocation, climate classification, habitat descriptions (e.g., seashore, grassland, forest, agricultural fields), and plant trait information concerning growth form and duration (e.g., annual vs. perennial). We also included extensive details of the methodology used to measure leaf damage, including seasons and months of sampling, age of leaves, and the method used to estimate percentage area missing. We anticipate that these data will make it possible to test important hypotheses in the plant?herbivore literature, including the plant apparency hypothesis, the latitudinal-herbivory defense hypothesis, the resource availability hypothesis, and the macroevolutionary escalation of defense hypothesis.
Address
Corporate Author Thesis
Publisher (up) Ecological Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0012-9658 ISBN Medium
Area Expedition Conference
Notes doi: 10.1890/13-1741.1 Approved no
Call Number EcoFoG @ webmaster @ Serial 575
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Author Chave, J.; Piponiot, C.; Maréchaux, I.; de Foresta, H.; Larpin, D.; Fischer, F.J.; Derroire, G.; Vincent, G.; Hérault, B.
Title Slow rate of secondary forest carbon accumulation in the Guianas compared with the rest of the Neotropics Type Journal Article
Year 2020 Publication Ecological Applications Abbreviated Journal Ecol. Appl.
Volume 30 Issue 1 Pages e02004
Keywords biomass; carbon; forest; French Guiana; regeneration; secondary forests; tropics; accumulation rate; Bayesian analysis; biomass; carbon sequestration; chronosequence; fertility; old-growth forest; pioneer species; regeneration; secondary forest; Costa Rica; French Guiana; Guyana Shield; Goupia glabra; Laetia procera; Xylopia
Abstract Secondary forests are a prominent component of tropical landscapes, and they constitute a major atmospheric carbon sink. Rates of carbon accumulation are usually inferred from chronosequence studies, but direct estimates of carbon accumulation based on long-term monitoring of stands are rarely reported. Recent compilations on secondary forest carbon accumulation in the Neotropics are heavily biased geographically as they do not include estimates from the Guiana Shield. We analysed the temporal trajectory of aboveground carbon accumulation and floristic composition at one 25-ha secondary forest site in French Guiana. The site was clear-cut in 1976, abandoned thereafter, and one large plot (6.25 ha) has been monitored continuously since. We used Bayesian modeling to assimilate inventory data and simulate the long-term carbon accumulation trajectory. Canopy change was monitored using two aerial lidar surveys conducted in 2009 and 2017. We compared the dynamics of this site with that of a surrounding old-growth forest. Finally, we compared our results with that from secondary forests in Costa Rica, which is one of the rare long-term monitoring programs reaching a duration comparable to our study. Twenty years after abandonment, aboveground carbon stock was 64.2 (95% credibility interval 46.4, 89.0) Mg C/ha, and this stock increased to 101.3 (78.7, 128.5) Mg C/ha 20 yr later. The time to accumulate one-half of the mean aboveground carbon stored in the nearby old-growth forest (185.6 [155.9, 200.2] Mg C/ha) was estimated at 35.0 [20.9, 55.9] yr. During the first 40 yr, the contribution of the long-lived pioneer species Xylopia nitida, Goupia glabra, and Laetia procera to the aboveground carbon stock increased continuously. Secondary forest mean-canopy height measured by lidar increased by 1.14 m in 8 yr, a canopy-height increase consistent with an aboveground carbon accumulation of 7.1 Mg C/ha (or 0.89 Mg C·ha−1·yr−1) during this period. Long-term AGC accumulation rate in Costa Rica was almost twice as fast as at our site in French Guiana. This may reflect higher fertility of Central American forest communities or a better adaptation of the forest tree community to intense and frequent disturbances. This finding may have important consequences for scaling-up carbon uptake estimates to continental scales.
Address INPHB, Institut National Polytechnique Félix Houphouët-Boigny, Yamoussoukro, Cote d'Ivoire
Corporate Author Thesis
Publisher (up) Ecological Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 19395582 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 914
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Author Odonne, G.; van den Bel, M.; Burst, M.; Brunaux, O.; Bruno, M.; Dambrine, E.; Davy, D.; Desprez, M.; Engel, J.; Ferry, B.; Freycon, V.; Grenand, P.; Jérémie, S.; Mestre, M.; Molino, J.-F.; Petronelli, P.; Sabatier, D.; Hérault, B.
Title Long-term influence of early human occupations on current forests of the Guiana Shield Type Journal Article
Year 2019 Publication Ecology Abbreviated Journal Ecology
Volume 100 Issue 10 Pages e02806
Keywords Amazonian forest; archaeology; ethnobotany; Guiana Shield; historical ecology; pre-Columbian settlements; ring-ditched hills; alluvial plain; anthropogenic effect; archaeology; basal area; database; ethnobotany; forest ecosystem; historical ecology; occupation; paleoecology; species diversity; Amazonia; French Guiana; Guyana Shield; Annonaceae; Arecaceae; Burseraceae; Lauraceae; Lecythidaceae; Brazil; forest; French Guiana; human; occupation; tree; Brazil; Forests; French Guiana; Humans; Occupations; Trees
Abstract To decipher the long-term influences of pre-Columbian land occupations on contemporary forest structure, diversity, and functioning in Amazonia, most of the previous research focused on the alluvial plains of the major rivers of the Amazon basin. Terra firme, that is, nonflooded forests, particularly from the Guiana Shield, are yet to be explored. In this study, we aim to give new insights into the subtle traces of pre-Columbian influences on present-day forests given the archaeological context of terra firme forests of the Guiana Shield. Following archaeological prospects on 13 sites in French Guiana, we carried out forest inventories inside and outside archaeological sites and assessed the potential pre-Columbian use of the sampled tree species using an original ethnobotanical database of the Guiana Shield region. Aboveground biomass (320 and 380 T/ha, respectively), basal area (25–30 and 30–35 m2/ha, respectively), and tree density (550 and 700 stem/ha, respectively) were all significantly lower on anthropized plots (As) than on nonanthropized plots (NAs). Ancient human presence shaped the species composition of the sampled forests with Arecaceae, Burseraceae, and Lauraceae significantly more frequent in As and Annonaceae and Lecythidaceae more frequent in NAs. Although alpha diversity was not different between As and NAs, the presence of pre-Columbian sites enhances significantly the forest beta diversity at the landscape level. Finally, trees with edible fruits are positively associated with pre-Columbian sites, whereas trees used for construction or for their bark are negatively associated with pre-Columbian sites. Half a millennium after their abandonment, former occupied places from the inner Guiana Shield still bear noticeable differences with nonanthropized places. Considering the lack of data concerning archaeology of terra firme Amazonian forests, our results suggest that pre-Columbian influences on the structure (lower current biomass), diversity (higher beta diversity), and composition (linked to the past human tree uses) of current Amazonian forests might be more important than previously thought. © 2019 by the Ecological Society of America
Address Institut National Polytechnique Félix Houphouet-Boigny (INP-HB), Yamoussoukro, Ivory Coast, Cote d'Ivoire
Corporate Author Thesis
Publisher (up) Ecological Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 00129658 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 919
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Author Srivastava, D.S.; Céréghino, R.; Trzcinski, M.K.; MacDonald, A.A.M.; Marino, N.A.C.; Mercado, D.A.; Leroy, C.; Corbara, B.; Romero, G.Q.; Farjalla, V.F.; Barberis, I.M.; Dézerald, O.; Hammill, E.; Atwood, T.B.; Piccoli, G.C.O.; Ospina-Bautista, F.; Carrias, J.-F.; Leal, J.S.; Montero, G.; Antiqueira, P.A.P.; Freire, R.; Realpe, E.; Amundrud, S.L.; de Omena, P.M.; Campos, A.B.A.
Title Ecological response to altered rainfall differs across the Neotropics Type Journal Article
Year 2020 Publication Ecology Abbreviated Journal Ecology
Volume 101 Issue 4 Pages e02984
Keywords contingency; distributed experiment; freshwater; global change biology; macroinvertebrates; phytotelmata; precipitation; aquatic ecosystem; climate change; climate conditions; ecosystem response; extreme event; functional group; invertebrate; Neotropical Region; rainfall; species pool; Bacteria (microorganisms); Invertebrata; rain; animal; climate change; drought; ecosystem; invertebrate; Animals; Climate Change; Droughts; Ecosystem; Invertebrates; Rain
Abstract There is growing recognition that ecosystems may be more impacted by infrequent extreme climatic events than by changes in mean climatic conditions. This has led to calls for experiments that explore the sensitivity of ecosystems over broad ranges of climatic parameter space. However, because such response surface experiments have so far been limited in geographic and biological scope, it is not clear if differences between studies reflect geographic location or the ecosystem component considered. In this study, we manipulated rainfall entering tank bromeliads in seven sites across the Neotropics, and characterized the response of the aquatic ecosystem in terms of invertebrate functional composition, biological stocks (total invertebrate biomass, bacterial density) and ecosystem fluxes (decomposition, carbon, nitrogen). Of these response types, invertebrate functional composition was the most sensitive, even though, in some sites, the species pool had a high proportion of drought-tolerant families. Total invertebrate biomass was universally insensitive to rainfall change because of statistical averaging of divergent responses between functional groups. The response of invertebrate functional composition to rain differed between geographical locations because (1) the effect of rainfall on bromeliad hydrology differed between sites, and invertebrates directly experience hydrology not rainfall and (2) the taxonomic composition of some functional groups differed between sites, and families differed in their response to bromeliad hydrology. These findings suggest that it will be difficult to establish thresholds of “safe ecosystem functioning” when ecosystem components differ in their sensitivity to climatic variables, and such thresholds may not be broadly applicable over geographic space. In particular, ecological forecast horizons for climate change may be spatially restricted in systems where habitat properties mediate climatic impacts, and those, like the tropics, with high spatial turnover in species composition. © 2020 by the Ecological Society of America
Address Departamento de Ciencias Biológicas, Universidad de Caldas, Caldas, 170001, Colombia
Corporate Author Thesis
Publisher (up) Ecological Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 00129658 (Issn) ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 979
Permanent link to this record
 

 
Author Peguero, Guille ; Ferrin, Miquel ; Sardans, Jordi ; Verbruggen, Erik ; Ramirez-Rojas , Irène ; Van Langenhove, Leandro ; Verryckt, Lore T. ; Murienne, Jérôme ; Iribar, Amaia ; Zinger, Lucie ; Grau, Oriol ; Orivel, Jérome ; Stahl, Clement ; Courtois, Elodie A. ; Asensio, Dolores ; Gargallo-Garriga, Albert ; Llusia, Joan ; Margalef, Olga ; Ogaya, Roma ; Richter, Andreas ; Janssens, Ivan A. ; Penuelas, Josep
Title Decay of similitary across tropical forest communities: integrating spatial distance with soil nutrients Type Journal Article
Year 2021 Publication Ecology Abbreviated Journal
Volume 103 Issue 2 Pages e03599
Keywords
Abstract Understanding the mechanisms that drive the change of biotic assemblages over space and time is the main quest of community ecology. Assessing the relative importance of dispersal and environmental species selection in a range of organismic sizes and motilities has been a fruitful strategy. A consensus for whether spatial and environmental distances operate similarly across spatial scales and taxa, however, has yet to emerge. We used censuses of four major groups of organisms (soil bacteria, fungi, ground insects, and trees) at two observation scales (1-m2 sampling point vs. 2,500-m2 plots) in a topographically standardized sampling design replicated in two tropical rainforests with contrasting relationships between spatial distance and nutrient availability. We modeled the decay of assemblage similarity for each taxon set and site to assess the relative contributions of spatial distance and nutrient availability distance. Then, we evaluated the potentially structuring effect of tree composition over all other taxa. The similarity of nutrient content in the litter and topsoil had a stronger and more consistent selective effect than did dispersal limitation, particularly for bacteria, fungi, and trees at the plot level. Ground insects, the only group assessed with the capacity of active dispersal, had the highest species turnover and the flattest nonsignificant distance−decay relationship, suggesting that neither dispersal limitation nor nutrient availability were fundamental drivers of their community assembly at this scale of analysis. Only the fungal communities at one of our study sites were clearly coordinated with tree composition. The spatial distance at the smallest scale was more important than nutrient selection for the bacteria, fungi, and insects. The lower initial similarity and the moderate variation in composition identified by these distance-decay models, however, suggested that the effects of stochastic sampling were important at this smaller spatial scale. Our results highlight the importance of nutrients as one of the main environmental drivers of rainforest communities irrespective of organismic or propagule size and how the overriding effect of the analytical scale influences the interpretation, leading to the perception of greater importance of dispersal limitation and ecological drift over selection associated with environmental niches at decreasing observation scales.
Address
Corporate Author Thesis
Publisher (up) Ecological Society of America Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes Approved no
Call Number EcoFoG @ webmaster @ Serial 1022
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