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Tremolieres, M.; Noel, V.; Herault, B. |
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Title |
Phosphorus and nitrogen allocation in Allium ursinum on an alluvial floodplain (Eastern France). Is there an effect of flooding history? |
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Journal Article |
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Year |
2009 |
Publication |
Plant and Soil |
Abbreviated Journal |
Plant Soil |
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324 |
Issue |
1-2 |
Pages |
279-289 |
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Allium ursinum; Flooding history; Nitrogen; Nutrient bioavailability; Phosphorus; Rhine |
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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. |
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[Tremolieres, Michele; Noel, Valerie] Inst Bot, LHYGES, UMR 7517, F-67083 Strasbourg, France, Email: michele.tremolieres@bota-ulp.u-strasbg.fr |
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SPRINGER |
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0032-079X |
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ISI:000271028800020 |
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EcoFoG @ eric.marcon @ |
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99 |
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Parelle, J.; Zapater, M.; Scotti-Saintagne, C.; Kremer, A.; Jolivet, Y.; Dreyer, E.; Brendel, O. |
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Title |
Quantitative trait loci of tolerance to waterlogging in a European oak (Quercus robur L.): physiological relevance and temporal effect patterns |
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Journal Article |
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Year |
2007 |
Publication |
Plant Cell and Environment |
Abbreviated Journal |
Plant Cell Environ. |
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30 |
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4 |
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422-434 |
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allelic substitution effect; correlation clustering; epinasty; hypertrophied lenticel; multi-environment model; root hypoxia |
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Quercus robur L. is a mid-European broadleaved tree species that grows readily on temporary waterlogged soils. An experiment aiming to identify potential markers of tolerance to waterlogging in this species and to assess the degree of genetic control over the corresponding traits was conducted. Quantitative trait loci (QTL) were assessed in an F-1 progeny for responses to waterlogging, and the relevance of the observed traits as markers of tolerance was investigated using a precise description of the time course of their expression. Five significant QTL involved in the response to waterlogging were identified. In particular, QTL were detected for the development of hypertrophied lenticels and for the degree of leaf epinasty, but not for the formation of adventitious roots. A multi-environment QTL model allowed a detailed description of the time course (7 weeks) of the allelic substitution effect of some of these QTL. Correlation clustering identified significant clusters of QTL, at inter-trait as well as at intra-trait level. These clusters suggest the occurrence of a genetically controlled response cascade to waterlogging. |
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UHP, UMR 1137, Ctr INRA Nancy, F-54280 Champenoux, France, Email: brendel@nancy.inra.fr |
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BLACKWELL PUBLISHING |
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0140-7791 |
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ISI:000244419700005 |
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EcoFoG @ eric.marcon @ |
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219 |
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Dutech, C.; Maggia, L.; Tardy, C.; Joly, H.I.; Jarne, P. |
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Title |
Tracking a genetic signal of extinction-recolonization events in a neotropical tree species: Vouacapoua americana aublet in french guiana |
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Journal Article |
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Year |
2003 |
Publication |
Evolution |
Abbreviated Journal |
Evolution |
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57 |
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12 |
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2753-2764 |
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Keywords |
allelic richness; caesalpinioideae; chloroplast DNA; climatic changes; cytonuclear disequilibrium; legummosae; microsatellite loci; tropical rainforest |
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Drier periods from the late Pleistocene and early Holocene have been hypothesized to have caused the disappearance of various rainforest species over large geographical areas in South America and restricted the extant populations to mesic sites. Subsequent improvement in climatic conditions has been associated with recolonization. Changes in population size associated with these extinction-recolonization events should have affected genetic diversity within species. However, these historical hypotheses and their genetic consequences have rarely been tested in South America. Here, we examine the diversity of the chloroplast and nuclear genomes in a Neotropical rainforest tree species, Vouacapoua americana (Leguminosae, Caesalpinioideae) in French Guiana. The chloroplast diversity was analyzed using a polymerase chain reaction-restriction fragment length polymorphism method (six pairs of primers) in 29 populations distributed over most of French Guiana, and a subset of 17 populations was also analyzed at nine polymorphic microsatellite loci. To determine whether this species has experienced extinction-recolonization, we sampled populations in areas supposedly not or only slightly affected by climatic changes, where the populations would not have experienced frequent extinction, and in areas that appear to have been recently recolonized. In the putatively recolonized areas, we found patches of several thousands of hectares homogeneous for chloroplast variation that can be interpreted as the effect of recolonization processes from several geographical origins. In addition, we observed that, for both chloroplast and nuclear genomes, the populations in newly recolonized areas exhibited a significantly smaller allelic richness than others. Controlling for geographic distance, we also detected a significant correlation between chloroplast and nuclear population differentiation. This result indicates a cytonuclear disequilibrium that can be interpreted as a historical signal of a genetic divergence between fragmented populations. In conclusion, the spatial genetic structure of contemporary V. americana populations shows evidence that this species has experienced large extinction-recolonization events, which were possibly caused by past climatic change. |
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CIRAD Foret, Silvolab, Ecol Mol, F-97387 Kourou, France, Email: laruent.maggia@cirad.fr |
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SOC STUDY EVOLUTION |
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0014-3820 |
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ISI:000188061800007 |
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EcoFoG @ eric.marcon @ |
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241 |
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Duplais, C.; Estevez, Y. |
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Tandem Biocatalysis Unlocks the Challenging de Novo Production of Plant Natural Products |
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Journal Article |
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2017 |
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ChemBioChem |
Abbreviated Journal |
ChemBioChem |
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18 |
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22 |
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2192-2195 |
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alkaloids; biosynthesis; enzyme catalysis; protein engineering; terpenes |
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Intimate partnership: Knowledge of the biocatalytic cascades in different cellular compartments is limited, but deciphering these systems in nature can be used to inspire synthetic strategies. Two studies report new insights into the biosynthesis of alkaloids and sesterterpenoids in plants. This highlight presents these novel biotransformations to illustrate how tandem biocatalysis can impact the future of natural product production. |
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1439-7633 |
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EcoFoG @ webmaster @ |
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780 |
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Touchard, A.; Aili, S.R.; Fox, E.G.P.; Escoubas, P.; Orivel, J.; Nicholson, G.M.; Dejean, A. |
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Title |
The biochemical toxin arsenal from ant venoms |
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Journal Article |
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2016 |
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Toxins |
Abbreviated Journal |
Toxins |
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8 |
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1 |
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30 |
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Alkaloids; Ant venom; Enzymes; Formic acid; Peptides; Toxins; Venom biochemistry |
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Ants (Formicidae) represent a taxonomically diverse group of hymenopterans with over 13,000 extant species, the majority of which inject or spray secretions from a venom gland. The evolutionary success of ants is mostly due to their unique eusociality that has permitted them to develop complex collaborative strategies, partly involving their venom secretions, to defend their nest against predators, microbial pathogens, ant competitors, and to hunt prey. Activities of ant venom include paralytic, cytolytic, haemolytic, allergenic, pro-inflammatory, insecticidal, antimicrobial, and pain-producing pharmacologic activities, while non-toxic functions include roles in chemical communication involving trail and sex pheromones, deterrents, and aggregators. While these diverse activities in ant venoms have until now been largely understudied due to the small venom yield from ants, modern analytical and venomic techniques are beginning to reveal the diversity of toxin structure and function. As such, ant venoms are distinct from other venomous animals, not only rich in linear, dimeric and disulfide-bonded peptides and bioactive proteins, but also other volatile and non-volatile compounds such as alkaloids and hydrocarbons. The present review details the unique structures and pharmacologies of known ant venom proteinaceous and alkaloidal toxins and their potential as a source of novel bioinsecticides and therapeutic agents. © 2016 by the authors; licensee MDPI, Basel, Switzerland. |
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Laboratoire Écologie Fonctionnelle et Environnement, 118 Route de Narbonne, Toulouse, France |
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Export Date: 8 February 2016 |
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EcoFoG @ webmaster @ |
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656 |
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Lecante, A.; Robert, F.; Lebrini, M.; Roos, C. |
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Title |
Inhibitive Effect of Siparuna Guianensis Extracts on the Corrosion of Low Carbon Steel in Acidic Media |
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Journal Article |
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2011 |
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International Journal of Electrochemical Science |
Abbreviated Journal |
Int.J.Electrochem.Sci. |
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6 |
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11 |
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5249-5264 |
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Alkaloids extract; corrosion inhibition; C38 steel; EIS; raman spectroscopy |
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The present study examines the effect of alkaloids extract from Siparuna guianensis leaves and stems on corrosion of C38 steel in 0.1 M HCl using electrochemical impedance spectroscopy (EIS), potentiodynamic polarization technique and Raman spectroscopy. The protection efficiency is better with stems alkaloids extract. The inhibition was assumed to occur via adsorption of inhibitor molecules on the metal surface. The influence of stems alkaloids extract concentration on corrosion of low carbon steel in 0.1 M HCl was studied. The inhibition efficiency obtained from impedance and polarization measurements was in a good agreement and was found to increase with increasing concentration of alkaloids extract up to 50 mg/L for stems extract. The adsorption of the extract on the low carbon steel surface obeys the Langmuir adsorption. |
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Laboratoire Matériaux et Molécules en Milieu Amazonien, UAG-UMR ECOFOG, Campus Trou Biran, Cayenne 97337, French Guiana |
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EcoFoG @ webmaster @ |
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374 |
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Anouhe, J.-B.S.; Niamké, F.B.; Faustin, M.; Virieux, D.; Pirat, J.-L.; Adima, A.A.; Kati-Coulibaly, S.; Amusant, N. |
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The role of extractives in the natural durability of the heartwood of Dicorynia guianensis Amsh: new insights in antioxydant and antifungal properties |
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Journal Article |
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2018 |
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Annals of Forest Science |
Abbreviated Journal |
Annals of Forest Science |
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75 |
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1 |
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Alkaloid; Antifungal; Antioxidant; Dicorynia guianensis; Heartwood; Natural durability; Phenols |
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Key message: The natural durability of Dicorynia guianensis Amsh’s Heartwood is conferred by the high content of antioxidant phenolic compounds, especially tannins and flavonoids combined with the presence of fungistatic alkaloids. The content of phenolic compounds increases according to the natural durability classes, from durable wood (class 2) to moderately durable wood (class 3) and correlated to the antioxidant capacity.
Context: The heartwood of Dicorynia guianensis Amsh is resistant to white rot fungi decay, but the mechanism of this natural durability is not fully elucidated.
Aims: Biochemical studies were carried out in order to better understand the role of extractives in natural durability of D. guianensis.
Methods: The powders from durable and moderately durable heartwood were extracted with methanol, ethanol, and hot water. The quantity of total phenols, tannins, and flavonoids as well as antioxidant activity, evaluated by 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) were determined using colorimetric methods. Antifungal activity was assessed by using two white rot fungi. The bioactive fractions and compounds were obtained using bio-guided fractionation, HPLC isolation, MS and RMN spectroscopic analyses.
Results: Durable woods contain higher amounts of heartwood extract and antioxidant activity. Antioxidant activity was highly correlated with the content of phenolics. The purification of the most antioxidant fraction FII affords the characterization of (+)-catechin (−)-epicatechin, neoastilbin, astilbin, and isoastilbin. Alkaloid fraction FIII exhibits dose-dependent fungistatic activity against Pycnoporus sanguineus Linnaeus and Trametes versicolor Quelet.
Conclusion: Phenolic antioxidants and fungistatic alkaloids positively impact the natural durability of D. guianensis. |
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AM2N, Institut Charles Gerhardt, UMR 5253, ENSCM 8 rue de l’Ecole Normale, Montpellier, France |
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Export Date: 19 February 2018 |
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EcoFoG @ webmaster @ |
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791 |
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Carrias, J.-F.; Céréghino, R.; Brouard, O.; Pélozuelo, L.; Dejean, A.; Couté, A.; Corbara, B.; Leroy, C. |
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Two coexisting tank bromeliads host distinct algal communities on a tropical inselberg |
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Journal Article |
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2014 |
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Plant Biology |
Abbreviated Journal |
Plant Biol. |
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16 |
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5 |
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997-1004 |
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Algae; Bromeliaceae; Inselberg; Neotropics; Phytotelmata; Aechmea; algae; Bromeliaceae; Bumilleriopsis; Catopsis berteroniana; Chlorella (unclassified Chlorophyceae); Chlorella (unclassified Trebouxiophyceae); Chlorella sp.; Cyanobacteria; Eukaryota; Invertebrata; Protozoa |
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The tank bromeliads Aechmea aquilega (Salisb.) and Catopsis berteroniana (Schultes f.) coexist on a sun-exposed Neotropical inselberg in French Guiana, where they permit conspicuous freshwater pools to form that differ in size, complexity and detritus content. We sampled the algal communities (both eukaryotic and cyanobacterial taxa, including colourless forms) inhabiting either A. aquilega (n = 31) or C. berteroniana (n = 30) and examined differences in community composition and biomass patterns in relation to several biotic and abiotic variables. Chlorella sp. and Bumilleriopsis sp. were the most common taxa and dominated the algal biomass in A. aquilega and C. berteroniana, respectively. Using a redundancy analysis, we found that water volume, habitat complexity and the density of phagotrophic protozoa and collector-gatherer invertebrates were the main factors explaining the distribution of the algal taxa among the samples. Hierarchical clustering procedures based on abundance and presence/absence data clearly segregated the samples according to bromeliad species, revealing that the algal communities in the smaller bromeliad species were not a subset of the communities found in the larger bromeliad species. We conclude that, even though two coexisting tank bromeliad populations create adjacent aquatic habitats, each population hosts a distinct algal community. Hence, bromeliad diversity is thought to promote the local diversity of freshwater algae in the Neotropics. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands. |
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IRD, UMR AMAP (botAnique et bioinforMatique de l'Architecture des Plantes), Montpellier, France |
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Blackwell Publishing Ltd |
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14388677 (Issn) |
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Export Date: 2 September 2014; Coden: Pbiof; Correspondence Address: Carrias, J.-F.; Clermont Université, Université Blaise Pascal, BP 10448, F-63000 Clermont-Ferrand, France; email: j-francois.carrias@univ-bpclermont.fr; Funding Details: LQ13C020005, NSFC, National Natural Science Foundation of China |
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EcoFoG @ webmaster @ |
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560 |
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Fayad, I.; Baghdadi, N.; Bailly, J.-S.; Barbier, N.; Gond, V.; Herault, B.; El Hajj, M.; Fabre, F.; Perrin, J. |
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Regional scale rain-forest height mapping using regression-kriging of spaceborne and airborne LiDAR data: Application on French Guiana |
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2016 |
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Remote Sensing |
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Remote Sensing |
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8 |
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3 |
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240 |
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Airborne LiDAR; Canopy height mapping; Forests; French Guiana; ICESat GLAS |
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LiDAR data has been successfully used to estimate forest parameters such as canopy heights and biomass. Major limitation of LiDAR systems (airborne and spaceborne) arises from their limited spatial coverage. In this study, we present a technique for canopy height mapping using airborne and spaceborne LiDAR data (from the Geoscience Laser Altimeter System (GLAS)). First, canopy heights extracted from both airborne and spaceborne LiDAR were extrapolated from available environmental data. The estimated canopy height maps using Random Forest (RF) regression from airborne or GLAS calibration datasets showed similar precisions (~6 m). To improve the precision of canopy height estimates, regression-kriging was used. Results indicated an improvement in terms of root mean square error (RMSE, from 6.5 to 4.2 m) using the GLAS dataset, and from 5.8 to 1.8 m using the airborne LiDAR dataset. Finally, in order to investigate the impact of the spatial sampling of future LiDAR missions on canopy height estimates precision, six subsets were derived from the initial airborne LiDAR dataset. Results indicated that using the regression-kriging approach a precision of 1.8 m on the canopy height map was achievable with a flight line spacing of 5 km. This precision decreased to 4.8 m for flight line spacing of 50 km. © 2016 by the authors. |
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BRGM, 3 Avenue Claude Guillemin, Orléans, France |
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Export Date: 22 April 2016 |
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EcoFoG @ webmaster @ |
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675 |
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Sierra, J.; Daudin, D.; Domenach, A.M.; Nygren, P.; Desfontaines, L. |
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Nitrogen transfer from a legume tree to the associated grass estimated by the isotopic signature of tree root exudates: A comparison of the N-15 leaf feeding and natural N-15 abundance methods |
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Journal Article |
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2007 |
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European Journal of Agronomy |
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Eur. J. Agron. |
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27 |
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2-4 |
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178-186 |
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agroforestry; box model; gliricidia sepium; N-15 fractionation; root turnover; tree pruning |
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Abstract |
Nitrogen (N) transfer from legume trees to associated crops is a key factor for the N economy of low-input agroforestry systems. In this work, we presented a new approach to estimate N transfer based on the N-15 content of root exudates and N released by root turnover of the donor plant (Gliricidia sepium) and the temporal change of the N-15 content of the receiver plant (Dichanthium aristatum). The study was carried out in greenhouse using two isotopic methods: N-15 leaf feeding (LF) and the natural N-15 abundance (NA). Measurements of exudate N-15 were made at several dates before and after tree pruning. A time-dependent box model was devised to quantify N transfer in time and to make comparisons between the isotopic methods. In NA, although tree roots and exudates presented a similar N-15 signature before tree pruning, exudates were strongly depleted in N-15 after pruning. In LF, exudates were always depleted in N-15 in relation to tree roots. Hence, the current assumption used in N transfer studies concerning the equal N-15/N-14 distribution in tissues of the donor plant and in its excreted N was not confirmed in our study. Before pruning, N transfer functioned as a two-N-source system (soil N and exudates N) and both isotopic methods provided similar estimates: 11-12% for LF and 10-15% for NA. Calculations per-formed with the model indicated that N transfer occurred with small or nil fractionation of N-15 in exudates. After pruning, there was a third N source associated with N released from tree root turnover. During this period, the isotopic signature of the receiver plant showed a transient state due to the progressive decrease of N-15 content of that N source. The amount of N derived from the tree represented 65% of the total N content of the. grass at the end of the experiments. (c) 2007 Elsevier B.V. All rights reserved. |
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INRA, Unite Agropedioclimat, UR135, Petit Bourg 97170, Guadeloupe, Email: jorge.sierra@antilles.inra.fr |
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ELSEVIER SCIENCE BV |
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1161-0301 |
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ISI:000249798900003 |
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EcoFoG @ eric.marcon @ |
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157 |
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