| |
Records |
Links |
|
Author |
Tindo, M.; Kenne, M.; Dejean, A. |
|
| |
Title |
Advantages of multiple foundress colonies in Belonogaster juncea juncea L.: greater survival and increased productivity |
Type |
Journal Article |
| |
Year |
2008 |
Publication |
Ecological Entomology |
Abbreviated Journal |
Ecol. Entomol. |
|
| |
Volume |
33 |
Issue |
2 |
Pages |
293-297 |
|
| |
Keywords |
colony development; evolution of eusociality; fitness; Polistinae; productivity |
|
| |
Abstract  |
1. The ecological hypothesis predicts that multiple foundress colonies of social wasps may have a better survival rate and produce more brood per capita than single foundress colonies. With the aim of verifying if these characteristics exist in the primitively eusocial wasp species Belonogaster juncea juncea (L.), we monitored 49 foundations, including 13 single and 36 multiple foundress colonies, in Cameroon. 2. Multiple foundress colonies were significantly more successful than single foundress colonies in producing at least one adult. 3. The total productivity of the colonies increased significantly with the number of associated foundresses, but the productivity per capita did not. No single foundress colony reached the sexual phase, while eight (21.6%) multiple foundress colonies did. Males were produced in only five colonies, so that the sex ratio was biased in favour of females. 4. These results suggest that because of the strong ecological constraints on solitary nesting, survival and high colony productivity are two advantages of multiple foundress colonies in B. j. juncea. 5. The decreasing per capita productivity concomitant with an increasing number of females noted in this study illustrates once again Michener's paradox. The coefficient of variance of the per capita productivity significantly decreased with group size, as Wenzel and Pickering suggested in the model they created to explain the paradox. 6. Ecological factors may act in conjunction with other factors, such as genetic relatedness between associated foundresses, to promote joining behaviour in B. j. juncea. |
|
| |
Address |
[Tindo, Maurice; Kenne, Martin] Univ Douala, Fac Sci, BP Douala, Cameroon, Email: jtindo2000@yahoo.fr |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
BLACKWELL PUBLISHING |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0307-6946 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
ISI:000253710000017 |
Approved |
no |
|
| |
Call Number |
EcoFoG @ eric.marcon @ |
Serial |
142 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Fortunel, C.; Fine, P.V.A.; Baraloto, C. |
|
| |
Title |
Leaf, stem and root tissue strategies across 758 Neotropical tree species |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Functional Ecology |
Abbreviated Journal |
Funct. Ecol. |
|
| |
Volume |
26 |
Issue |
5 |
Pages |
1153-1161 |
|
| |
Keywords |
French Guiana; Functional trade-offs; Leaf economics; Peru; Plant traits; Tropical forest; Wood economics |
|
| |
Abstract |
1. Trade-offs among functional traits reveal major plant strategies that can give insight into species distributions and ecosystem processes. However, current identification of plant strategies lacks the integration of root structural traits together with leaf and stem traits. 2. We examined correlations among 14 traits representing leaf, stem and woody root tissues. Traits were measured on 1084 individuals representing 758 Neotropical tree species, across 13 sites representative of the environmental variation encompassed by three widespread habitats (seasonally flooded, clay terra firme and white-sand forests) at opposite ends of Amazonia (French Guiana and Peru). 3. Woody root traits were closely aligned with stem traits, but not with leaf traits. Altogether leaf, stem and woody root traits delineated two orthogonal axes of functional trade-offs: a first axis defined by leaf traits, corresponding to a 'leaf economics spectrum', and a second axis defined by covarying stem and woody root traits, corresponding to a 'wood economics spectrum'. These axes remained consistent when accounting for species evolutionary history with phylogenetically independent contrasts. 4. Despite the strong species turnover across sites, the covariation among root and stem structural traits as well as their orthogonality to leaf traits were strongly consistent across habitats and regions. 5. We conclude that root structural traits mirrored stem traits rather than leaf traits in Neotropical trees. Leaf and wood traits define an integrated whole-plant strategy in lowland South American forests that may contribute to a more complete understanding of plant responses to global changes in both correlative and modelling approaches. We suggest further meta-analyses in expanded environmental and geographic zones to determine the generality of this pattern. © 2012 The Authors. Functional Ecology © 2012 British Ecological Society. |
|
| |
Address |
Department of Biology, University of Florida, Gainesville, FL, 32611, United States |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
02698463 (Issn) |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Export Date: 10 October 2012; Source: Scopus; Coden: Fecoe; doi: 10.1111/j.1365-2435.2012.02020.x; Language of Original Document: English; Correspondence Address: Fortunel, C.; INRA, UMR Ecologie des Forêts de Guyane, BP 709, 97387 Kourou Cedex, France; email: claire.fortunel@ecofog.gf |
Approved |
no |
|
| |
Call Number |
EcoFoG @ webmaster @ |
Serial |
440 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ferry, B.; Bontemps, J.-D.; Blanc, L.; Baraloto, C. |
|
| |
Title |
Is climate a stronger driver of tree growth than disturbance? A comment on Toledo et al. (2011) |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Journal of Ecology |
Abbreviated Journal |
J. Ecol. |
|
| |
Volume |
100 |
Issue |
5 |
Pages |
1065-1068 |
|
| |
Keywords |
Basal area change; Bolivia; Climate; Disturbance; Logging; Plant-climate interactions; Tree growth; Tropical forest |
|
| |
Abstract |
1.A recent article published by Toledo (2011b) investigates the effects of spatial variations in climate and soil, and of logging disturbance, on tree and forest growth in Bolivia. It concludes that climate is the strongest driver of tree and forest growth and that climate change may therefore have large consequences for forest productivity and carbon sequestration. However, serious methodological and conceptual discrepancies have been found that challenge these conclusions. 2.Because of an errant coding of 'time after logging' in the regression analysis, and because floristic changes induced by logging could not be incorporated into the analysis, the effect of logging on the average diameter growth is likely to have been strongly underestimated. 3.Basal area growth was improperly calculated as basal area change, and it displayed surprisingly high values, even among unlogged plots. We hypothesize that either these plots may be actually located in secondary forests recovering from past logging, or measurement biases may have hampered the data set. 4.Regardless of climate-growth relationships established across these plots, any inference concerning the potential effects of climate change on forest growth would require a specific quantitative assessment. 5.Synthesis. It is critical to re-assess the relative weight of climate and logging disturbance as driving factors of tree and forest growth, and to find an explanation for the very high basal area increment reported among the unlogged plots. We provide specific recommendations for further analyses of this and similar data sets. © 2012 British Ecological Society. |
|
| |
Address |
INRA, UMR Ecologie des Forêts de Guyane, 97379 Kourou, French Guiana |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
00220477 (Issn) |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Cited By (since 1996): 1; Export Date: 4 September 2012; Source: Scopus; Coden: Jecoa; doi: 10.1111/j.1365-2745.2011.01895.x; Language of Original Document: English; Correspondence Address: Ferry, B.; AgroParisTech, ENGREF-Nancy, UMR 1092, F-54000 Nancy, France; email: bruno.ferry@engref.agroparistech.fr |
Approved |
no |
|
| |
Call Number |
EcoFoG @ webmaster @ |
Serial |
426 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Baraloto, C.; Herault, B.; Paine, C.E.T.; Massot, H.; Blanc, L.; Bonal, D.; Molino, J.-F.; Nicolini, E.A.; Sabatier, D. |
|
| |
Title |
Contrasting taxonomic and functional responses of a tropical tree community to selective logging |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Journal of Applied Ecology |
Abbreviated Journal |
J. Appl. Ecol. |
|
| |
Volume |
49 |
Issue |
4 |
Pages |
861-870 |
|
| |
Keywords |
Canopy gap dynamics; Disturbance; French Guiana; Functional diversity; Functional evenness; Functional traits; Light partitioning; Species richness; Tropical rain forest |
|
| |
Abstract |
1.Considerable debate surrounds the extent to which tropical forests can be managed for resource extraction while conserving biodiversity and ecosystem properties, which depend on functional composition. Here we evaluate the compatibility of these aims by examining the effects of logging on taxonomic and functional diversity and composition in a tropical forest. 2.Twenty years after selective logging, we inventoried 4140 stems regenerating in logging gaps and adjacent undisturbed areas, and we integrated a database of 13 functional traits describing leaf and wood economics of tropical trees. 3.We found no differences in taxonomic and functional richness among habitats, but logging gaps had significantly higher taxonomic and functional evenness. 4.Logging also effected striking, long-term changes in both species and functional composition. In particular, the xylem density of recruits in logging gaps was 6% less than in unlogged forests, leaves were 11% less tough and had 6-13% greater mineral nutrient concentrations. 5.Synthesis and applications. Our results suggest that managers of tropical forests should limit overall surface area converted to logging gaps by creating fewer, larger gaps during selective logging, to reduce impacts on the taxonomic and functional composition of the regenerating stand. Our results suggest that managers of tropical forests should limit overall surface area converted to logging gaps by creating fewer, larger gaps during selective logging, to reduce impacts on the taxonomic and functional composition of the regenerating stand. © 2012 The Authors. Journal of Applied Ecology © 2012 British Ecological Society. |
|
| |
Address |
CIRAD-ES, Research Unit 'Biens et Services des Ecosystémes Forestiers tropicaux', Embrapa Amazonia Oriental, Caixa Postal, 48, Belem, Para – CEP 66095-100, Brazil |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
00218901 (Issn) |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Export Date: 30 July 2012; Source: Scopus; Coden: Japea; doi: 10.1111/j.1365-2664.2012.02164.x; Language of Original Document: English; Correspondence Address: Baraloto, C.; INRA, UMR 'Ecologie des Forêts de Guyane', 97387 Kourou Cedex, French Guiana; email: chris.baraloto@ecofog.gf |
Approved |
no |
|
| |
Call Number |
EcoFoG @ webmaster @ |
Serial |
410 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Herault, B.; Bachelot, B.; Poorter, L.; Rossi, V.; Bongers, F.; Chave, J.; Paine, C.E.T.; Wagner, F.; Baraloto, C. |
|
| |
Title |
Functional traits shape ontogenetic growth trajectories of rain forest tree species |
Type |
Journal Article |
| |
Year |
2011 |
Publication |
Journal of Ecology |
Abbreviated Journal |
J. Ecol. |
|
| |
Volume |
99 |
Issue |
6 |
Pages |
1431-1440 |
|
| |
Keywords |
Bayesian modelling; Functional traits; Growth modelling; Leaf economics; Leaf-height-seed strategy; Plant development and life-history traits; Plant strategy; Stem economics; Tropical rain forest |
|
| |
Abstract |
1.Functional traits are posited to explain interspecific differences in performance, but these relationships are difficult to describe for long-lived organisms such as trees, which exhibit strong ontogenetic changes in demographic rates. Here, we use a size-dependent model of tree growth to test the extent to which of 17 functional traits related to leaf and stem economics, adult stature and seed size predict the ontogenetic trajectory of tree growth. 2.We used a Bayesian modelling framework to parameterize and contrast three size-dependent diameter growth models using 16years of census data from 5524 individuals of 50 rain forest tree species: a size-dependent model, a size-dependent model with species-specific parameters and a size-dependent model based on functional traits. 3.Most species showed clear hump-shaped ontogenetic growth trajectories and, across species, maximum growth rate varied nearly tenfold, from 0.58 to 5.51mmyear-1. Most species attained their maximum growth at 60% of their maximum size, whereas the magnitude of ontogenetic changes in growth rate varied widely among species. 4.The Trait-Model provided the best compromise between explained variance and model parsimony and needed considerably fewer parameters than the model with species terms. 5.Stem economics and adult stature largely explained interspecific differences in growth strategy. Maximum absolute diameter growth rates increased with increasing adult stature and leaf δ13C and decreased with increasing wood density. Species with light wood had the greatest potential to modulate their growth, resulting in hump-shaped ontogenetic growth curves. Seed size and leaf economics, generally thought to be of paramount importance for plant performance, had no significant relationships with the growth parameters. 6.Synthesis. Our modelling approach offers a promising way to link demographic parameters to their functional determinants and hence to predict growth trajectories in species-rich communities with little parameter inflation, bridging the gap between functional ecology and population demography. © 2011 The Authors. Journal of Ecology © 2011 British Ecological Society. |
|
| |
Address |
Department of Biology, University of Florida, Gainesville, FL 32611, United States |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
00220477 (Issn) |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Export Date: 21 October 2011; Source: Scopus; Coden: Jecoa; doi: 10.1111/j.1365-2745.2011.01883.x; Language of Original Document: English; Correspondence Address: Hérault, B.; Université des Antilles et de la Guyane, UMR Ecologie des Forêts de Guyane, 97387 Kourou Cedex, France; email: bruno.herault@ecofog.gf |
Approved |
no |
|
| |
Call Number |
EcoFoG @ webmaster @ |
Serial |
342 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Gourlet-Fleury, S.; Rossi, V.; Rejou-Mechain, M.; Freycon, V.; Fayolle, A.; Saint-André, L.; Cornu, G.; Gérard, J.; Sarrailh, J.-M.; Flores, O.; Baya, F.; Billand, A.; Fauvet, N.; Gally, M.; Henry, M.; Hubert, D.; Pasquier, A.; Picard, N. |
|
| |
Title |
Environmental filtering of dense-wooded species controls above-ground biomass stored in African moist forests |
Type |
Journal Article |
| |
Year |
2011 |
Publication |
Journal of Ecology |
Abbreviated Journal |
J. Ecol. |
|
| |
Volume |
99 |
Issue |
4 |
Pages |
981-990 |
|
| |
Keywords |
Basal area; Central African Republic; Determinants of plant community diversity and structure; Life-history strategy; Soil fertility; Species sorting; Vital rates; Water reserve; Wood density; aboveground biomass; basal area; climate change; data set; database; diameter; forest ecosystem; forest inventory; life history trait; nutrient availability; physical property; plant community; resource availability; soil fertility; soil nutrient; soil texture; soil type; stem; tropical forest; wood; Central African Republic |
|
| |
Abstract |
1.Regional above-ground biomass estimates for tropical moist forests remain highly inaccurate mostly because they are based on extrapolations from a few plots scattered across a limited range of soils and other environmental conditions. When such conditions impact biomass, the estimation is biased. The effect of soil types on biomass has especially yielded controversial results. 2.We investigated the relationship between above-ground biomass and soil type in undisturbed moist forests in the Central African Republic. We tested the effects of soil texture, as a surrogate for soil resources availability and physical constraints (soil depth and hydromorphy) on biomass. Forest inventory data were collected for trees ≥20cm stem diameter in 2754 0.5ha plots scattered over 4888km2. The plots contained 224 taxons, of which 209 were identified to species. Soil types were characterized from a 1:1000000 scale soil map. Species-specific values for wood density were extracted from the CIRAD's data base of wood technological properties. 3.We found that basal area and biomass differ in their responses to soil type, ranging from 17.8m2ha-1 (217.5tha-1) to 22.3m2ha-1 (273.3tha-1). While shallow and hydromorphic soils support forests with both low stem basal area and low biomass, forests on deep resource-poor soils are typically low in basal area but as high in biomass as forests on deep resource-rich soils. We demonstrated that the environmental filtering of slow growing dense-wooded species on resource-poor soils compensates for the low basal area, and we discuss whether this filtering effect is due to low fertility or to low water reserve. 4.Synthesis. We showed that soil physical conditions constrained the amount of biomass stored in tropical moist forests. Contrary to previous reports, our results suggest that biomass is similar on resource-poor and resource-rich soils. This finding highlights both the importance of taking into account soil characteristics and species wood density when trying to predict regional patterns of biomass. Our findings have implications for the evaluation of biomass stocks in tropical forests, in the context of the international negotiations on climate change. © 2011 The Authors. Journal of Ecology © 2011 British Ecological Society. |
|
| |
Address |
CIRAD, BP 4035, Libreville, Gabon |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
00220477 (Issn) |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
Cited By (since 1996): 1; Export Date: 23 October 2011; Source: Scopus; Coden: Jecoa; doi: 10.1111/j.1365-2745.2011.01829.x; Language of Original Document: English; Correspondence Address: Gourlet-Fleury, S.; Cirad, UR BandSEF, Biens et Services des Ecosystèmes Forestiers tropicaux, Campus International de Baillarguet, TA C-105/D, F-34398, Montpellier, France; email: sylvie.gourlet-fleury@cirad.fr |
Approved |
no |
|
| |
Call Number |
EcoFoG @ webmaster @ |
Serial |
361 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Bourguignon, T.; Sobotnik, J.; Lepoint, G.; Martin, J.M.; Hardy, O.J.; Dejean, A.; Roisin, Y. |
|
| |
Title |
Feeding ecology and phylogenetic structure of a complex neotropical termite assemblage, revealed by nitrogen stable isotope ratios |
Type |
Journal Article |
| |
Year |
2011 |
Publication |
Ecological Entomology |
Abbreviated Journal |
Ecol. Entomol. |
|
| |
Volume |
36 |
Issue |
2 |
Pages |
261-269 |
|
| |
Keywords |
Diet diversity; feeding groups; Isoptera; phylogenetic autocorrelation |
|
| |
Abstract |
2. Nitrogen stable isotopes (hereafter delta 15N) were used to place termites from French Guiana rainforests along a wood-soil decomposition gradient, to test (i) whether feeding group assignation based on morphological characters was accurate and actually represented diet specialisation thresholds, and (ii) to what extent the dietary specialization of species is explained by phylogeny (phylogenetic autocorrelation). 3. delta 15N values vary over a range of 13 parts per thousand, suggesting that diet diversification contributes to the high species diversity in French Guiana. delta 15N values span a similar interval in all Termitidae subfamilies. Ranges of different subfamilies broadly overlap, although each of them diversified preferentially on one side of the wood-soil decomposition gradient. Congeneric species share similar feeding habits, whereas distant species tend to feed on distinct substrates. 4. Feeding groups did not completely match stable isotope data: there was no discontinuity between Groups III and IV, and no correlation between anatomical criteria used to distinguish these groups and delta 15N values. Nor was there any consistent difference in delta 15N values between wood feeders of the families Rhinotermitidae (Group I) and Termitidae (Group II). We also suggest that species feeding outside the wood-soil gradient should be distinguished for their peculiar feeding requirements. |
|
| |
Address |
[Sobotnik, Jan] Acad Sci Czech Republic, Inst Organ Chem & Biochem, Res Team Infochem, CR-16610 Prague 6, Czech Republic, Email: sobotnik@uochb.cas.cz |
|
| |
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 |
0307-6946 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
ISI:000288456300016 |
Approved |
no |
|
| |
Call Number |
EcoFoG @ webmaster @ |
Serial |
302 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Ferrer, A.; Dixon, A.F.; Gibernau, M.; Hemptinne, J.L. |
|
| |
Title |
Ovarian dynamics and specialisation in ladybirds |
Type |
Journal Article |
| |
Year |
2010 |
Publication |
Ecological Entomology |
Abbreviated Journal |
Ecol. Entomol. |
|
| |
Volume |
35 |
Issue |
1 |
Pages |
100-103 |
|
| |
Keywords |
Ladybird beetles; oocyte resorption; ovarian dynamics; specialisation |
|
| |
Abstract |
2. This hypothesis was tested by comparing a generalist and a specialist ladybird species belonging to the same genus. 3. A resorption index was calculated for females of both species subjected to several starvation regimes. This index indicated that over a period of fasting of 3 days, the intensity of resorption was greater in the generalist than the specialist. When food was again supplied, oogenesis resumed and within 1 day was faster in the generalist than in the specialist. 4. As predicted, the resorption of oocytes and replenishment occurred faster in the generalist than in the specialist species. This is the first time, to our knowledge, that the speed and intensity of the ovarian dynamics of a predatory insect have been linked to its way of life. |
|
| |
Address |
[Ferrer, Aurelie; Hemptinne, Jean-Louis] Univ Toulouse ENFAT, CNRS, UMR 5174, F-31326 Castanet Tolosan, France, Email: jean-louis.hemptinne@educagri.fr |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
WILEY-BLACKWELL PUBLISHING, INC |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0307-6946 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
ISI:000273454300013 |
Approved |
no |
|
| |
Call Number |
EcoFoG @ eric.marcon @ |
Serial |
86 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Clair, B.; Almeras, T.; Yamamoto, H.; Okuyama, T.; Sugiyama, J. |
|
| |
Title |
Mechanical behavior of cellulose microfibrils in tension wood, in relation with maturation stress generation |
Type |
Journal Article |
| |
Year |
2006 |
Publication |
Biophysical Journal |
Abbreviated Journal |
Biophys. J. |
|
| |
Volume |
91 |
Issue |
3 |
Pages |
1128-1135 |
|
| |
Keywords |
|
|
| |
Abstract |
A change in cellulose lattice spacing can be detected during the release of wood maturation stress by synchrotron x-ray diffraction experiment. The lattice strain was found to be the same order of magnitude as the macroscopic strain. The fiber repeat distance, 1.033 nm evaluated for tension wood after the release of maturation stress was equal to the conventional wood values, whereas the value before stress release was larger, corresponding to a fiber repeat of 1.035 nm, nearly equal to that of cotton and ramie. Interestingly, the fiber repeat varied from 1.033 nm for wood to 1.040 nm for algal cellulose, with an increasing order of lateral size of cellulose microfibrils so far reported. These lines of experiments demonstrate that, before the stress release, the cellulose was in a state of tension, which is, to our knowledge, the first experimental evidence supporting the assumption that tension is induced in cellulose microfibrils. |
|
| |
Address |
Kyoto Univ, Res Inst Sustainable Humanosphere, Uji, Kyoto, Japan, Email: sugiyama@rish.kyoto-u.ac.jp |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
BIOPHYSICAL SOCIETY |
Place of Publication |
|
Editor |
|
|
| |
Language |
|
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0006-3495 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
ISI:000239086800039 |
Approved |
no |
|
| |
Call Number |
EcoFoG @ eric.marcon @ |
Serial |
224 |
|
| Permanent link to this record |
| |
|
| |
|
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 |
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 |
|
| Permanent link to this record |
