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Author Tremolieres, M.; Noel, V.; Herault, B.
Title Phosphorus and nitrogen allocation in Allium ursinum on an alluvial floodplain (Eastern France). Is there an effect of flooding history? Type Journal Article
Year 2009 Publication Plant and Soil Abbreviated Journal Plant Soil
Volume 324 Issue 1-2 Pages 279-289
Keywords Allium ursinum; Flooding history; Nitrogen; Nutrient bioavailability; Phosphorus; Rhine
Abstract The change in phosphorus and nitrogen content in a common geophyte spring species, Allium ursinum, is studied in alluvial forests in relation to three flooding histories related to river regulation: (1) annually flooded, (2) unflooded for 30 years, and (3) unflooded for 200 years. Flood suppression leads to a reduction of available P soil content as well as decreasing the biomass and the amount of phosphorus in plants, but has no significant effect on N plant content. Plant N:P ratio increases with the suppression of floods and is primarily driven by soil N:P ratios, in turn markedly linked to the total nitrogen in the soil. We highlighted a lower nutrient accumulation in leaves during plant growth in unflooded forests. Overall, our results suggest that P was the main limiting factor in unflooded forests while nitrogen was the main limiting factor in annually flooded forests. Flood suppression strongly affects the morphology and nutrient uptake by Allium ursinum and thus nutrient cycling in riverine forests.
Address [Tremolieres, Michele; Noel, Valerie] Inst Bot, LHYGES, UMR 7517, F-67083 Strasbourg, France, Email: michele.tremolieres@bota-ulp.u-strasbg.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-079X ISBN Medium
Area Expedition Conference
Notes ISI:000271028800020 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 99
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Author Roux, O.; Martin, J.M.; Ghomsi, N.T.; Dejean, A.
Title A Non-lethal Water-based Removal-reapplication Technique for Behavioral Analysis of Cuticular Compounds of Ants Type Journal Article
Year 2009 Publication Journal of Chemical Ecology Abbreviated Journal J. Chem. Ecol.
Volume 35 Issue 8 Pages 904-912
Keywords Ants; Behavioral assay; Behavioral ecology; Camponotus blandus; Chemical composition; Chemical ecology; Cuticular hydrocarbons; Gas chromatography-mass spectrometry; Live dummies; Solenopsis saevissima; Methods
Abstract Interspecific relationships among insects are often mediated by chemical cues, including non-volatile cuticular compounds. Most of these compounds are hydrocarbons that necessitate the use of solvents for their extraction, identification, and manipulation during behavioral assays. The toxicity of these solvents often precludes the removal and reapplication of hydrocarbons from and to live insects. As a consequence, dummies often are used in behavioral assays, but their passivity can bias the behavior of the responding insects. To overcome these limitations, we propose a method where cuticular compounds are extracted from live ants by placing them into glass vials half-filled with tepid water (ca. 34A degrees C) and vigorously shaking the vials to form an emulsion whose supernatant can be analyzed and/or reapplied to other ants. We demonstrate that cuticular compounds can be extracted from workers of the red fire ant, Solenopsis saevissima, and reapplied to the cuticle of workers from a sympatric species, Camponotus blandus (both Hymenoptera: Formicidae), while keeping the ants alive. Gas chromatographic-mass spectrometric analysis and behavioral assays were used to confirm the successful transfer of the behaviorally active compounds.
Address [Roux, Olivier; Martin, Jean-Michel; Dejean, Alain] Ecol Forets Guyane, CNRS, UMR 8172, F-97379 Kourou, France, Email: oroux@cict.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0098-0331 ISBN Medium
Area Expedition Conference
Notes ISI:000269954400006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 104
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Author Brechet, L.; Ponton, S.; Roy, J.; Freycon, V.; Couteaux, M.M.; Bonal, D.; Epron, D.
Title Do tree species characteristics influence soil respiration in tropical forests? A test based on 16 tree species planted in monospecific plots Type Journal Article
Year 2009 Publication Plant and Soil Abbreviated Journal Plant Soil
Volume 319 Issue 1-2 Pages 235-246
Keywords Fine root; Litter quality; Nutrient cycling; Plant soil interactions; Soil respiration; Tropical plantations
Abstract The high spatial variability of soil respiration in tropical rainforests is well evaluated, but influences of biotic factors are not clearly understood. This study underlines the influence of tree species characteristics on soil respiration across a 16-monospecific plot design in a tropical plantation of French Guiana. A large variability of soil CO2 fluxes was observed among plots (i.e. 2.8 to 6.8 μmol m(-2) s(-1)) with the ranking being constant across seasons. There were no significant relationships between soil respiration and soil moisture or soil temperature, neither spatially, nor seasonally. The variability of soil respiration was mainly explained by quantitative factors such as leaf litterfall and basal area. Surprisingly, no significant relationship was observed between soil respiration and root biomass. However, the influence of substrate quality was revealed by a strong relationship between soil respiration and litterfall P (and litterfall N, to a lesser extent).
Address [Ponton, Stephane] Natl Inst Agr Res INRA Ctr Rech Nancy, Forest Ecol & Ecophysiol Unit, UMR EEF, F-54280 Seichamps, France, Email: ponton@nancy.inra.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0032-079X ISBN Medium
Area Expedition Conference
Notes ISI:000266143400020 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 110
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Author Paine, C.E.T.; Harms, K.E.
Title Quantifying the effects of seed arrival and environmental conditions on tropical seedling community structure Type Journal Article
Year 2009 Publication Oecologia Abbreviated Journal Oecologia
Volume 160 Issue 1 Pages 139-150
Keywords Community assembly; Dispersal; Niche differentiation; Seed addition; Variance partitioning
Abstract Though it is recognized that both stochastic and deterministic processes structure all communities, empirical assessments of their relative importance are rare, particularly within any single community. In this paper, we quantify the dynamic effects of dispersal assembly and niche assembly on the seedling layer in a diverse neotropical rain forest. The two theories make divergent predictions regarding the roles of seed arrival and environmental heterogeneity in generating community structure. Put simply, dispersal assembly posits that the stochasticity inherent to seed arrival structures communities, whereas niche assembly suggests that heterogeneity in post-dispersal environmental conditions is more important. We experimentally sowed 15,132 seeds of eight tree species at varying levels of density and diversity. Every six months we censused the seedlings that germinated and assessed the abiotic and biotic conditions of each plot. We assessed the density, diversity, and species composition of three nested subsets of the seedling layer: seedlings germinated from sown seeds, all seedlings germinated between July 2003 and 2004, and all woody seedlings. We partitioned the variance in density and diversity of each subset of the seedling layer into components representing seed-addition treatments and environmental conditions at 6- to 12-month intervals. Seed additions initially explained more variance in the density and diversity than did environmental heterogeneity for seven of eight sown species, but explained little variance in the density or diversity of the entire seedling layer. Species composition was better explained by seed-addition treatments than by environmental heterogeneity for all three subsets and in all time periods. Nevertheless, the variance in community structure explained by seed-addition treatments declined over the two years following germination, presaging shifts in the relative importance of dispersal assembly and niche assembly. Our study quantifies how dispersal assembly and niche assembly may vary among the components of an ecological community and shift dynamically through time.
Address [Paine, C. E. Timothy; Harms, Kyle E.] Louisiana State Univ, Dept Biol Sci, Baton Rouge, LA 70803 USA, Email: timothy.paine@ecofog.gf
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0029-8549 ISBN Medium
Area Expedition Conference
Notes ISI:000265100500014 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 116
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Author Dejean, A.; Grangier, J.; Leroy, C.; Orivel, J.
Title Predation and aggressiveness in host plant protection: a generalization using ants from the genus Azteca Type Journal Article
Year 2009 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften
Volume 96 Issue 1 Pages 57-63
Keywords Aggressiveness; Ant-plant relationships; Biotic defence; Predation
Abstract In studying the ant genus Azteca, a Neotropical group of arboreal species, we aimed to determine the extent to which the ants use predation and/or aggressiveness to protect their host plants from defoliating insects. We compared a territorially dominant, carton-nester, Azteca chartifex, and three plant-ant species. Azteca alfari and Azteca ovaticeps are associated with the myrmecophyte Cecropia (Cecropiaceae) and their colonies shelter in its hollow branches; whereas Azteca bequaerti is associated with Tococa guianensis (Melastomataceae) and its colonies shelter in leaf pouches situated at the base of the laminas. Whereas A. bequaerti workers react to the vibrations transmitted by the lamina when an alien insect lands on a leaf making it unnecessary for them to patrol their plant, the workers of the three other species rather discover prey by contact. The workers of all four species use a predatory behaviour involving spread-eagling alien insects after recruiting nestmates at short range, and, in some cases, at long range. Because A. alfari and A. ovaticeps discard part of the insects they kill, we deduced that the workers' predatory behaviour and territorial aggressiveness combine in the biotic defence of their host tree.
Address [Dejean, Alain; Leroy, Celine] CNRS, UMR Ecol Forets Guyane 8172, F-97379 Kourou, France, Email: alain.dejean@wanadoo.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-1042 ISBN Medium
Area Expedition Conference
Notes ISI:000261791000006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 125
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Author Herault, B.; Bornet, A.; Tremolieres, M.
Title Redundancy and niche differentiation among the European invasive Elodea species Type Journal Article
Year 2008 Publication Biological Invasions Abbreviated Journal Biol. Invasions
Volume 10 Issue 7 Pages 1099-1107
Keywords biological traits; functional equivalence; invasivness; niche overlapping; waterweeds
Abstract Community ecologists implicitly assume redundancy when they aggregate species into functional groups. But there have been remarkably few empirical efforts to investigate the accuracy of this concept in situ. The concept of redundancy could be roughly split into two components: the ecological redundancy (similar response to environmental variations involving similar ecological processes) and the functional redundancy (similar biological trait combinations shaping similar functional processes). Both types of redundancy are tested among the 3 invasive European Elodeas. In 11 sites and during two successive years 2004-2005, the cover growth rate of each Elodea species was monthly recorded. To test ecological redundancy, cover growth rates were related to a large suite of environmental variables. To test functional redundancy, 13 biological traits involved in competitive relationships were measured each month. Firstly, the redundancy hypothesis looks problematic for Elodea ernstiae. Indeed, the later possess numerous biological traits involved in light competition and niche overlap with the other Elodeas is very low. Secondly, ecological and functional redundancy can be successfully applied to Elodea canadensis and Elodea nuttallii. They share a large suite of biological traits leading to wide niche overlaps through the growing season. And the measured environmental variables do not differentially influence their growth rates, which are, in turn, controlled by a similar group of biological traits. In this way, the different invasiveness patterns of E. canadensis and E. nuttallii could be solely due to the ecological drift and their ecological dynamic could follow neutral rules.
Address [Herault, Bruno] Univ Antilles Guyane, INRA, UMR Ecol Forets Guyane, F-97379 Kourou, France, Email: Bruno.Herault@cirad.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1387-3547 ISBN Medium
Area Expedition Conference
Notes ISI:000258704400015 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 131
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Author Herault, B.; Thoen, D.
Title Diversity of plant assemblages in isolated depressional wetlands from Central-Western Europe Type Journal Article
Year 2008 Publication Biodiversity and Conservation Abbreviated Journal Biodivers. Conserv.
Volume 17 Issue 9 Pages 2169-2183
Keywords closed depressions; connectivity; fens; forest; grassland; habitat area; landscape matrix
Abstract A closed depression is defined as a geomorphologic element where a sediment depository is encircled by hillslopes. Despite the fact that closed depressions are often the only stagnant water points in many European landscapes, few ecological researches on their plant assemblages have been done. The main goal of this study was to give first results of the environmental factors responsible for the vegetation composition, richness and rarity in the closed depressions of the Lorraine biogeographical district (Belgium, France and grand-duche de Luxembourg). We surveyed for plant presence 85 forest and 77 grassland closed depressions. For each site, wetland area, local environmental factors and regional connectivities registered. For each species, the Ellenberg values were compiled. To investigate the main source of variation in species composition and in species richness (including richness in rare species), Non-metric Multidimensional Scaling analyses and Generalized Linear Models were respectively used. Species pools in forest (forest and preforest species) and in grassland (bog plants, pioneers, helophytes) were quite different. In both landscapes, a gradient from plants typical of basic high-productive soils to plants typical of acid low-productive soils reflects a shared successional gradient. The accumulation of organic matter allowed the establishment of Sphagnum spp., which slowly acidified the soil and thus acted as ecosystem engineers for the arrival of bog plants. Moreover, the species composition was additionally driven by the plant light tolerance in forests and by the plant water requirements in grasslands. Mechanisms of species accumulation (increase in species richness) were different in forests and in grasslands: respectively related to the plant light tolerance and to the wetland area. At the regional level, the averaged soil productivity was negatively related to the richness in rare species. Indeed, perennial highly-competitive plants such as Glyceria spp., Iris pseudacorus or Urtica dioica impeded the establishment of smaller and rarer species. At the habitat level, isolated closed depressions (due to either low connectivity or low grazing pressure) have more habitat rare species, giving evidences of dispersal limitation in plant assemblages of closed depressions.
Address [Herault, Bruno] Inst Bot, Ctr Ecol Vegetale & Hydrol, F-67083 Strasbourg, France, Email: bruno.herault@cirad.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0960-3115 ISBN Medium
Area Expedition Conference
Notes ISI:000257486400008 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 135
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Author Christensen-Dalsgaard, K.K.; Ennos, A.R.; Fournier, M.
Title Are radial changes in vascular anatomy mechanically induced or an ageing process? Evidence from observations on buttressed tree root systems Type Journal Article
Year 2008 Publication Trees-Structure and Function Abbreviated Journal Trees-Struct. Funct.
Volume 22 Issue 4 Pages 543-550
Keywords wood; anatomy; mechanical loading; tree development; vessels
Abstract To investigate the effect of changes in mechanical loading conditions on radial anatomical patterns, we here compare the trunk with the roots in two locations of three species of buttressed trees. The proximal part of the buttress roots is highly mechanically loaded throughout juvenile growth whereas the distal part of the buttresses is though to be mechanically unimportant at formation but become progressively more mechanically loaded during growth. We measured the frequency and diameter of the vessels and the vessel area fraction, and from this calculated the specific conductivity of tissue samples of the core-, intermediate- and outer wood. As in previous studies there was an increase in vessel size, vessel area fraction and specific conductivity from the pith to the bark in the trunk. In the proximal part of the buttress roots, however, there was no increase in vessel size and conductivity from core wood and out in agreement with the high mechanical loading found here throughout growth. There was instead a decrease in vessel size, vessel area fraction and specific conductivity from core- to outer wood in the distal part of the buttress roots in accordance with the increase in mechanical loading. Hence, it appears that the radial anatomical patterns are not a passive function of cambial ageing but may be modified in response to local mechanical loading.
Address [Christensen-Dalsgaard, Karen K.] Univ Alberta, Edmonton, AB T6G 2E3, Canada, Email: kkchrist@ualberta.ca
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0931-1890 ISBN Medium
Area Expedition Conference
Notes ISI:000257385200014 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 136
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Author Grangier, J.; Dejean, A.; Male, P.J.G.; Orivel, J.
Title Indirect defense in a highly specific ant-plant mutualism Type Journal Article
Year 2008 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften
Volume 95 Issue 10 Pages 909-916
Keywords Allomerus decemarticulatus; Hirtella physophora; indirect defense; myrmecophytes; optimal defense theory
Abstract Although associations between myrmecophytes and their plant ants are recognized as a particularly effective form of protective mutualism, their functioning remains incompletely understood. This field study examined the ant-plant Hirtella physophora and its obligate ant associate Allomerus decemarticulatus. We formulated two hypotheses on the highly specific nature of this association: (1) Ant presence should be correlated with a marked reduction in the amount of herbivory on the plant foliage; (2) ant activity should be consistent with the “optimal defense” theory predicting that the most vulnerable and valuable parts of the plant are the best defended. We validated the first hypothesis by demonstrating that for ant-excluded plants, expanding leaves, but also newly matured ones in the long term, suffered significantly more herbivore damage than ant-inhabited plants. We showed that A. decemarticulatus workers represent both constitutive and inducible defenses for their host, by patrolling its foliage and rapidly recruiting nestmates to foliar wounds. On examining how these activities change according to the leaves' developmental stage, we found that the number of patrolling ants dramatically decreased as the leaves matured, while leaf wounds induced ant recruitment regardless of the leaf's age. The resulting level of these indirect defenses was roughly proportional to leaf vulnerability and value during its development, thus validating our second hypothesis predicting optimal protection. This led us to discuss the factors influencing ant activity on the plant's surface. Our study emphasizes the importance of studying both the constitutive and inducible components of indirect defense when evaluating its efficacy and optimality.
Address [Grangier, Julien; Dejean, Alain; Male, Pierre-Jean G.; Orivel, Jerome] Univ Toulouse 3, Lab Evolut & Diversite Biol, CNRS, UMR 5174, F-31062 Toulouse 9, France, Email: grangier@cict.fr
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-1042 ISBN Medium
Area Expedition Conference
Notes ISI:000259737600002 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 207
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Author LaPierre, L.; Hespenheide, H.; Dejean, A.
Title Wasps robbing food from ants: a frequent behavior? Type Journal Article
Year 2007 Publication Naturwissenschaften Abbreviated Journal Naturwissenschaften
Volume 94 Issue 12 Pages 997-1001
Keywords cleptobiosis; social wasps; charterginus; polybioides; plant-ants
Abstract Food robbing, or cleptobiosis, has been well documented throughout the animal kingdom. For insects, intrafamilial food robbing is known among ants, but social wasps (Vespidae; Polistinae) taking food from ants has, to the best of our knowledge, never been reported. In this paper, we present two cases involving social wasps robbing food from ants associated with myrmecophytes. (1) Polybioides tabida F. (Ropalidiini) rob pieces of prey from Tetraponera aethiops Smith (Formicidae; Pseudomyrmecinae) specifically associated with Barteria fistulosa Mast. (Passifloraceae). (2) Charterginus spp. (Epiponini) rob food bodies from myrmecophytic Cecropia (Cecropiaceae) exploited by their Azteca mutualists (Formicidae; Dolichoderinae) or by opportunistic ants (that also attack cleptobiotic wasps). We note here that wasps gather food bodies (1) when ants are not yet active; (2) when ants are active, but avoiding any contact with them by flying off when attacked; and (3) through the coordinated efforts of two to five wasps, wherein one of them prevents the ants from leaving their nest, while the other wasps freely gather the food bodies. We suggest that these interactions are more common than previously thought.
Address CNRS Guyane, UPS2561, UMR5174, F-97300 Cayenne, France, Email: llapierre@lowercolumbia.edu
Corporate Author Thesis
Publisher (down) SPRINGER Place of Publication Editor
Language Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0028-1042 ISBN Medium
Area Expedition Conference
Notes ISI:000250980800006 Approved no
Call Number EcoFoG @ eric.marcon @ Serial 153
Permanent link to this record