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Author ter Steege, H.; Pitman, N.C.A.; Sabatier, D.; Baraloto, C.; Salomão, R.P.; Guevara, J.E.; Phillips, O.L.; Castilho, C.V.; Magnusson, W.E.; Molino, J.-F.; Monteagudo, A.; Núñez Vargas, P.; Montero, J.C.; Feldpausch, T.R.; Coronado, E.N.H.; Killeen, T.J.; Mostacedo, B.; Vasquez, R.; Assis, R.L.; Terborgh, J.; Wittmann, F.; Andrade, A.; Laurance, W.F.; Laurance, S.G.W.; Marimon, B.S.; Marimon, B.-H.; Guimarães Vieira, I.C.; Amaral, I.L.; Brienen, R.; Castellanos, H.; Cárdenas López, D.; Duivenvoorden, J.F.; Mogollón, H.F.; Matos, F.D. de A.; Dávila, N.; García-Villacorta, R.; Stevenson Diaz, P.R.; Costa, F.; Emilio, T.; Levis, C.; Schietti, J.; Souza, P.; Alonso, A.; Dallmeier, F.; Montoya, A.J.D.; Fernandez Piedade, M.T.; Araujo-Murakami, A.; Arroyo, L.; Gribel, R.; Fine, P.V.A.; Peres, C.A.; Toledo, M.; Aymard C., G.A.; Baker, T.R.; Cerón, C.; Engel, J.; Henkel, T.W.; Maas, P.; Petronelli, P.; Stropp, J.; Zartman, C.E.; Daly, D.; Neill, D.; Silveira, M.; Paredes, M.R.; Chave, J.; Lima Filho, D. de A.; Jørgensen, P.M.; Fuentes, A.; Schöngart, J.; Cornejo Valverde, F.; Di Fiore, A.; Jimenez, E.M.; Peñuela Mora, M.C.; Phillips, J.F.; Rivas, G.; van Andel, T.R.; von Hildebrand, P.; Hoffman, B.; Zent, E.L.; Malhi, Y.; Prieto, A.; Rudas, A.; Ruschell, A.R.; Silva, N.; Vos, V.; Zent, S.; Oliveira, A.A.; Schutz, A.C.; Gonzales, T.; Trindade Nascimento, M.; Ramirez-Angulo, H.; Sierra, R.; Tirado, M.; Umaña Medina, M.N.; van der Heijden, G.; Vela, C.I.A.; Vilanova Torre, E.; Vriesendorp, C.; Wang, O.; Young, K.R.; Baider, C.; Balslev, H.; Ferreira, C.; Mesones, I.; Torres-Lezama, A.; Urrego Giraldo, L.E.; Zagt, R.; Alexiades, M.N.; Hernandez, L.; Huamantupa-Chuquimaco, I.; Milliken, W.; Palacios Cuenca, W.; Pauletto, D.; Valderrama Sandoval, E.; Valenzuela Gamarra, L.; Dexter, K.G.; Feeley, K.; Lopez-Gonzalez, G.; Silman, M.R. url  doi
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  Title Hyperdominance in the Amazonian Tree Flora Type Journal Article
  Year 2013 Publication Science Abbreviated Journal Science  
  Volume 342 Issue 6156 Pages 1243092  
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  Abstract The vast extent of the Amazon Basin has historically restricted the study of its tree communities to the local and regional scales. Here, we provide empirical data on the commonness, rarity, and richness of lowland tree species across the entire Amazon Basin and Guiana Shield (Amazonia), collected in 1170 tree plots in all major forest types. Extrapolations suggest that Amazonia harbors roughly 16,000 tree species, of which just 227 (1.4%) account for half of all trees. Most of these are habitat specialists and only dominant in one or two regions of the basin. We discuss some implications of the finding that a small group of species—less diverse than the North American tree flora—accounts for half of the world’s most diverse tree community.  
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  Call Number EcoFoG @ webmaster @ Serial 507  
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Author Sharma, K.; Degen, B.; Von Wuehlisch, G.; Singh, N.B. url  openurl
  Title Allozyme variation in eight natural populations of Pinus roxburghii Sarg. in India Type Journal Article
  Year 2002 Publication Silvae Genetica Abbreviated Journal Silvae Genet.  
  Volume 51 Issue 5-6 Pages 246-253  
  Keywords Allozymes; Differentiation; Genetic distance; Multilocus diversity; Pinus roxburghii; Variation; Enzymes; Forestry; Genes; Allozyme variations; Genetic engineering; Enzymes; Genes; Genetic Engineering; Pinus Roxburghii; Embryophyta; Pinus roxburghii  
  Abstract Seeds collected from eight populations of Chir pine (Pinus roxburghii SARG.) from the natural distribution range of the species in Himachal Himalayas in India were analysed isozymatically at 11 enzyme systems. For the enzyme systems studied, 25 gene loci were identified out of which 18 were polymorphic. The observed mean values for genetic variation were slightly lower than mean values reported for Pinus species (number of alleles: 1.65 compared to 2.36; effective number of alleles: 1.13 compared to 1.26; observed heterozygosity: 0.153 compared to 0.179). A small differentiation among populations and large variation within populations were reflected by small value of GST (0.04): Considering the different genetic parameters three populations seem favourable for gene conservation measures.  
  Address Silviculture Division, Forest Research Institute, Dehra Dun – 248 006, India  
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  Notes Cited By (since 1996): 4; Export Date: 22 October 2011; Source: Scopus; Coden: Sigea; Language of Original Document: English; Correspondence Address: Sharma, K.; Dr. Y. S. Parmar Univ. Hort./Forest., Reg. Horticultural Research Station, Jachh (Nurpur)-176 201 (HP), India Approved no  
  Call Number EcoFoG @ webmaster @ Serial 360  
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Author Latouche-Hallé, C.; Ramboer, A.; Bandou, E.; Caron, H.; Kremer, A. url  openurl
  Title Nuclear and chloroplast genetic structure indicate fine-scale spatial dynamics in a neotropical tree population Type Journal Article
  Year 2003 Publication Heredity Abbreviated Journal Heredity  
  Volume 91 Issue 2 Pages 181-190  
  Keywords Dicorynia guianensis; Gene flow; Genetic differentiation; Microsatellites; Spatial analysis; Tropical tree; gene flow; genetic structure; population genetics; spatial analysis; tree; tropical forest; Cell Nucleus; Chloroplasts; Cohort Studies; DNA, Plant; French Guiana; Genetic Markers; Pollen; Population Dynamics; Seeds; Trees; Variation (Genetics); French Guiana; Dicorynia guianensis; Embryophyta  
  Abstract Dicorynia guianensis is a canopy tree, endemic to the tropical rain forest of French Guiana. We compared generational and spatial genetic structure for maternally and biparentally inherited markers in two cohorts (adult and seedling) in order to infer processes shaping the distribution of genetic diversity. The study was conducted on a 40 ha study plot located at Paracou near Kourou, where 172 adults trees and 375 saplings were sampled. Aggregation of trees was therefore suggested at different distances, ranging from 100 to 400 m. There was a strong link between demographic and genetic spatial structures at small distances (less than 100 m) that is likely to be the consequence of restricted seed dispersal. Genetic differentiation was more pronounced between spatial aggregates than between cohorts. Despite the spatial differentiation, the species was able to maintain high levels of diversity for maternal genomes, suggesting rapid turnover of aggregates. Spatial autocorrelation was larger for chloroplast than nuclear markers indicating a strong asymmetry between pollen and seed flow. Fixation indices indicated a lower heterozygote deficiency for the adults, maybe because of gradual elimination of selfed trees. Genetic relatedness at lower distances was higher in adult trees than in saplings, as a result of generation overlapping in the adult cohort. Overall, our results confirm earlier biological knowledge about the dispersion mechanisms of the species, and lead to an enhanced role of spatial processes in the dynamics of genetic diversity of D. guianensis.  
  Address INRA Lab. Genet. Arbres Forestiers, BP45, 33611 Gazinet Cedex, France  
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  Notes Cited By (since 1996): 34; Export Date: 22 October 2011; Source: Scopus; Coden: Hdtya; doi: 10.1038/sj.hdy.6800296; PubMed ID: 12886285; Language of Original Document: English; Correspondence Address: Caron, H.; INRA Lab. Genet. Arbres Forestiers, BP45, 33611 Gazinet Cedex, France; email: caron@pierroton.inra.fr; Chemicals/CAS: DNA, Plant; Genetic Markers Approved no  
  Call Number EcoFoG @ webmaster @ Serial 358  
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Author Porth, I.; Scotti-Saintagne, C.; Barreneche, T.; Kremer, A.; Burg, K. url  openurl
  Title Linkage mapping of osmotic stress induced genes of oak Type Journal Article
  Year 2005 Publication Tree Genetics and Genomes Abbreviated Journal Tree Genet. Genomes  
  Volume 1 Issue 1 Pages 31-40  
  Keywords Est; Linkage map; Oak; Osmotic stress; Quercus ssp.; Fagaceae; Quercus; Quercus petraea; Quercus robur  
  Abstract Water stress affecting long-lived trees is an important challenge in forestry. Due to global climate change, forest trees will be threatened by extreme conditions like flooding or drought. It is necessary to understand differences in stress tolerance within certain species and to investigate putative relations on genomic level. In this study, osmotic stress induced genes of Quercus ssp. were positioned on two genetic linkage maps of oak. An intra-specific cross 3P*A4 of Quercus robur consisting of 88 offspring and an inter-specific cross 11P*QS29 of Q. robur and Q. petraea comprising 72 full-sibs were analyzed for the inheritance of 14 loci represented by 34 individual single nucleotide polymorphisms. Seven genes in the intra-cross, as well as other six genes in the inter-cross could be mapped and one gene could not be localised due to the severe distortion of the segregation. The collection of expressed sequences involved ribosomal proteins, members of the oxylase/oxygenase gene family, betaine aldehyde dehydrogenase, Dc3 promoter-binding factor, a putative member of the nodulin family, glutathione-S-transferase and proteins with unknown functions. In the inter-cross, two linked markers exhibited 89% deficiency of heterozygosity. Thirteen genes were positioned on ten different oak chromosomes and can serve as orthologous markers in comparative mapping studies within Fagaceae. © Springer-Verlag 2005.  
  Address INRA BIOGECO, 69 Route d'Arcachon, 33612 Cestas, France  
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  Notes Cited By (since 1996): 9; Export Date: 22 October 2011; Source: Scopus; doi: 10.1007/s11295-005-0005-1; Language of Original Document: English; Correspondence Address: Burg, K.; Division of Biogenetics and Natural Resources, Austrian Research Center Seibersdorf, 2444 Seibersdorf, Austria; email: kornel.burg@arcs.ac.at Approved no  
  Call Number EcoFoG @ webmaster @ Serial 357  
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Author Dejean, A.; Delabie, J.H.C.; Cerdan, P.; Gibernau, M.; Corbara, B. url  openurl
  Title Are myrmecophytes always better protected against herbivores than other plants? Type Journal Article
  Year 2006 Publication Biological Journal of the Linnean Society Abbreviated Journal Biol. J. Linn. Soc.  
  Volume 89 Issue 1 Pages 91-98  
  Keywords Ant-plant mutualism; Azteca; Maieta; Myrmecophytes; Plant protection; Tococa; ant; defoliation; field method; mutualism; myrmecophyte; plant-herbivore interaction; Azteca; Azteca bequaerti; Clidemia; Crematogaster laevis; Formicidae; Maieta; Maieta guianensis; Pheidole minutula; Tococa; Tococa guianensis  
  Abstract The present field study compared the degree of defoliation of three Guianian melastome, two myrmecophytes (i.e. plants sheltering ants in hollow structures) and Clidemia sp., a nonmyrmecophytic plant serving as a control. Maieta guianensis Aubl. hosted mostly Pheidole minutula Mayr whatever the area, whereas Tococa guianensis Aubl. hosted mostly Azteca bequaerti Wheeler along streams and Crematogaster laevis Mayr or Azteca sp. 1 in the understory where it never blossomed. Only Tococa, when sheltering A. bequaerti in what can be considered as a truly mutualistic relationship, showed significantly less defoliation than control plants. In the other associations, the difference was not significant, but P. minutula is mutualistic with Maieta because it furnishes some protection (exclusion experiments) plus nutrients (previous studies). When devoid of ants, Tococa showed significantly greater defoliation than control plants; therefore, it was deduced that Tococa probably lacks certain antidefoliator metabolites that control plants possess (both Tococa and control plants are protected by ground-nesting, plant-foraging ants, which is termed 'general myrmecological protection'). Consequently, plant-ants other than A. bequaerti probably also protect Tococa slightly, thus compensating for this deficiency and permitting it to live in the understory until treefall gaps provide the conditions necessary for seed production. © 2006 The Linnean Society of London.  
  Address Laboratoire de Psychologie Sociale de la Cognition (UMR CNRS 6024), Université Blaise Pascal, 34 avenue Carnot, 63037 Clermont-Ferrand Cedex, France  
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  Notes Cited By (since 1996): 9; Export Date: 22 October 2011; Source: Scopus; Coden: Bjlsb; doi: 10.1111/j.1095-8312.2006.00660.x; Language of Original Document: English; Correspondence Address: Dejean, A.; Laboratoire d'Evolution et Diversité Biologique (UMR CNRS 5174), Université Toulouse III, Bâtiment 4R3, 118 route de Narbonne, 31062 Toulouse Cedex, France; email: dejean@cict.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 355  
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Author Dejean, A.; Moreau, C.S.; Uzac, P.; Le Breton, J.; Kenne, M. url  openurl
  Title The predatory behavior of Pheidole megacephala Type Journal Article
  Year 2007 Publication Comptes Rendus Biologies Abbreviated Journal C. R. Biol.  
  Volume 330 Issue 9 Pages 701-709  
  Keywords Invasive ants; Landmarks; Pheidole megacephala; Predatory behavior; Recruitment; pheromone; ant; behavioral ecology; foraging behavior; invasive species; nest predation; pheromone; predator-prey interaction; animal experiment; ant; article; competitor species; controlled study; foraging behavior; host range; Isoptera; nest predation; nonhuman; predation; predator prey interaction; prey selection; species invasion; worker (insect); Animals; Ants; Feeding Behavior; Female; Isoptera; Predatory Behavior; Social Behavior; Formicidae; Hexapoda; Isoptera; Pheidole megacephala  
  Abstract We studied the foraging and predatory behaviors of the invasive African myrmicine ant, Pheidole megacephala (F.) in its native range. Workers can singly capture a wide range of insects, including relatively large prey items. For still larger prey, they recruit at short range those nestmates situated within reach of an alarm pheromone and together spread-eagle the insect. These behaviors are complimented by a long-range recruitment (of nestmates remaining in the nest) based on prey size. P. megacephala scouts also use long-range recruitment when they detect the landmarks of termites and competing ant species, thus permitting them to avoid confronting these termites and ants solitarily.  
  Address Département de biologie des organismes animaux, faculté des sciences, l'université de Douala, BP 24157, Douala, Cameroon  
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  ISSN 16310691 (Issn) ISBN Medium  
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  Notes Cited By (since 1996): 8; Export Date: 22 October 2011; Source: Scopus; Coden: Crboc; doi: 10.1016/j.crvi.2007.06.005; PubMed ID: 17720587; Language of Original Document: English; Correspondence Address: Dejean, A.; CNRS-Guyane, UPS 2561, UMR-CNRS 5174, 16, avenue André-Aron, 97300 Cayenne, France; email: alain.dejean@wanadoo.fr Approved no  
  Call Number EcoFoG @ webmaster @ Serial 354  
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Author Christensen-Dalsgaard, K.K.; Ennos, A.R.; Fournier, M. url  openurl
  Title Changes in hydraulic conductivity, mechanical properties, and density reflecting the fall in strain along the lateral roots of two species of tropical trees Type Journal Article
  Year 2007 Publication Journal of Experimental Botany Abbreviated Journal J. Exp. Bot.  
  Volume 58 Issue 15-16 Pages 4095-4105  
  Keywords Buttress roots; Density; Hydraulic conductivity; Hydraulic-mechanical trade-offs; Modulus of elasticity; Tropical trees; Wood; Elastic moduli; Hydraulic conductivity; Wood; Buttress roots; Hydraulic-mechanical trade-offs; Tropical trees; Forestry; water; article; biomechanics; histology; legume; physiology; plant root; plant stem; tree; wood; Xylopia; Biomechanics; Fabaceae; Plant Roots; Plant Stems; Trees; Water; Wood; Xylopia; Conductivity; Elastic Strength; Forestry; Wood  
  Abstract Roots have been described as having larger vessels and so greater hydraulic efficiency than the stem. Differences in the strength and stiffness of the tissue within the root system itself are thought to be an adaptation to the loading conditions experienced by the roots and to be related to differences in density. It is not known how potential mechanical adaptations may affect the hydraulic properties of the roots. The change in strength, stiffness, conductivity, density, sapwood area, and second moment of area distally along the lateral roots of two tropical tree species in which the strain is known to decrease rapidly was studied and the values were compared with those of the trunk. It was found that as the strain fell distally along the roots, so did the strength and stiffness of the tissue, whereas the conductivity increased exponentially. These changes appeared to be related to differences in density. In contrast to the distal-most roots, the tissue of the proximal roots had a lower conductivity and higher strength than that of the trunk. This suggests that mechanical requirements on the structure rather than the water potential gradient from roots to branches are responsible for the general pattern that roots have larger vessels than the stem. In spite of their increased transectional area, the buttressed proximal roots were subjected to higher levels of stress and had a lower total conductivity than the rest of the root system. © 2007 The Author(s).  
  Address AgroParisTech, LERFOB, Ecole Nationale du Genie Rural, des Eaux et Forêts, 14 Avenue Girardet-CS 4216, 54000 Nancy Cedex, France  
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  Notes Cited By (since 1996): 6; Export Date: 22 October 2011; Source: Scopus; Coden: Jeboa; doi: 10.1093/jxb/erm268; PubMed ID: 18039738; Language of Original Document: English; Correspondence Address: Christensen-Dalsgaard, K.K.; University of Manchester, Faculty of Life Sciences, Jackson's Mill, Manchester M60 1QD, United Kingdom; email: karen@cd-mail.dk; Chemicals/CAS: water, 7732-18-5; Water, 7732-18-5 Approved no  
  Call Number EcoFoG @ webmaster @ Serial 353  
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Author Christensen-Dalsgaard, K.K.; Ennos, A.R.; Fournier, M. url  openurl
  Title Interrelations between hydraulic and mechanical stress adaptations in woody plants Type Journal Article
  Year 2008 Publication Plant Signaling and Behavior Abbreviated Journal Plant. Signal. Behav.  
  Volume 3 Issue 7 Pages 463-465  
  Keywords Conductivity; Modulus of elasticity; Strain; Tree ecophysiology; Tropical trees; Wood anatomy; Yield stress  
  Abstract The fields of plant water relations and plant biomechanics have traditionally been studied separately even though often the same tissues are responsible for water transport and mechanical support. There is now increasing evidence that hydraulic and mechanical adaptations may influence one another. We studied the changes in the hydraulic and mechanical properties of the wood along lateral roots of two species of buttressed trees. In these roots, the mechanical contstraints quantified by strain measurements are known to decrease distally. Further, we investigated the effect of mechanical loading on the vessel anatomy in these and four other species of tropical trees. We found that as the strain decreased, the wood became progressively less stiff and strong but the conductivity increased exponentially. This was reflected in that adaptations towards re-enforcing mechanically loaded areas resulted in xylem with fewer and smaller vessels. In addition a controlled growth experiment on three tree species showed that drought adaptation may results in plants with stronger and stiffer tissue. Our results indicate that hydraulic and mechanical stress adaptations may be interrelated, and so support recent studied suggesting that physiological responses are complex balances rather than pure optimisations. ©2008 Landes Bioscience.  
  Address University of Alberta, Department of Renewable Resources, 4-44 Earth Science Bldg., Edmonton, AB T6G 2E3, Canada  
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  Notes Export Date: 25 January 2012; Source: Scopus; Language of Original Document: English; Correspondence Address: Christensen-Dalsgaard, K. K.; University of Alberta, Department of Renewable Resources, 4-44 Earth Science Bldg., Edmonton, AB T6G 2E3, Canada; email: kkchrist@ualberta.ca Approved no  
  Call Number EcoFoG @ webmaster @ Serial 380  
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Author Vincent, G.; Weissenbacher, E.; Sabatier, D.; Blanc, L.; Proisy, C.; Couteron, P. url  openurl
  Title Detection des variations de structure de peuplements en foret dense tropicale humide par lidar aeroporte Type Journal Article
  Year 2010 Publication Revue Francaise de Photogrammetrie et de Teledetection Abbreviated Journal Rev. Fr. Photogramm. Teledetect.  
  Volume 191 Issue Pages 42-51  
  Keywords Above-ground biomass estimation; Canopy height model; Stem diameter distribution; Tropical moist forest; Above ground biomass; Above ground level; Airborne LiDAR; Basal area; Canopy Height Models; Carbon stocks; Characterisation; Classical fields; Coefficient of variation; Diameter distributions; Digital terrain model; Flooded areas; Forest ecology; Forest structure; Forest type; High spatial resolution; Individual tree; LIDAR data; Light detection and ranging; Local statistics; Long term; Management issues; Natural forests; Natural variation; Pearson correlation coefficients; Quadratic mean diameter; Soil characteristics; Soil cover; Spatial changes; Spatial resolution; Stem density; Stem diameter; Stem height; Strong correlation; Tree height; Tropical moist forest; Tropical rain forest; Vegetation structure; Vertical accuracy; Water regime; Discriminant analysis; Ecology; Optical radar; Remote sensing; Soils; Statistics; Stem cells; Temperature control; Tropics; Vegetation; Forestry; Biomass; Discriminant Analysis; Ecology; Forest Canopy; Forestry; Radar; Remote Sensing; Stems; Temperature Control; Tropical Atmospheres  
  Abstract Characterisation of forest structure is a major stake for forestry, species conservation, carbon stock estimates and many forest ecology and management issues. At large scale natural forest structure tends to vary according to climate and geomorphomology (Paget, 1999; Steege et al., 2006) while soil characteristics (and notably water regime) and syMgenetic stage add some finer scale variation (Oldeman, 1989; Sabatier et al., 1997). Forest structure characterisation traditionally relies on field-based collection of individual tree dimensions such as stem diameter and stem height sampled across tracks of forest (Hall et al., 1998). However, such field intensive methods are costly, and of low accuracy regarding measures of tree heights. Airborne light detection and ranging (LiDAR) technology provides horizontal and vertical Information at high spatial resolutions and vertical accuracies (Lim et al., 2003; Hyyppä et al., 2004). It has the potential for gathering vegetation structure data over large areas rapidly at moderate cost and hence is of particular relevance for poorly sampled, difficult to access and largely unexplored tropical rainforests. In this study we examined the ability of airborne LiDAR to detect spatial changes in the structure of dense tropical rain forest and we probed this remote sensing approach against local statistics derived from stem diameters (i.e. classical field data information) mapped across a large track of forest at a long term experimental site in French Guyana. The large variability in forest structure occurring at the experimental site is du to natural variation of the soil cover (and notably drainage properties) combined with various logging intensities applied 15 years before the LiDAR data were acquired. On this basis ten different forest types were identified at the site (figure 1 and 3). Various stem based statistics were computed for a series of meshes with cells ranging from 30 by 30 m plots to 250 by 250 m plots. These statistics included basal area, stem density, quadratic mean diameter, and diameter distribution percentiles. Similarly local statistics were extracted either from the Canopy Height Model (e.g. median height, mean height, standard height deviation, height coefficient of variation, height percentiles, frequency of hits below 5 m above ground level). Additionally a wetness index (Böhner et al., 2002) was computed at each node of a 5 by 5 m grid from the Digital Terrain Model also extracted from the LiDAR data set. We used both types of cell statistics to discriminate the various forest types. Comparison between the two approaches for a range of spatial resolution is available from in table 1. Results indicate that LiDAR based statistics are essentially as powerful as field based statistics to discriminate forest types at coarse scale. This reflects the very strong correlation between the CHM and the field based stem diameter data. For example (figure 5) the Pearson correlation coefficient between median height and quadratic mean diameter for cells of 125 by 125 m is 0.945 (n=0.72). When a finer resolution is required however as for the detection of seasonally flooded bottomland forest along thalwegs, then LiDAR technology proves more efficient than field based inventories as it combines information from the DTM and the CHM. The wetness index alone correctly retrieves about 2 thirds of the seasonally flooded areas. All in all, discriminant analysis performance of the LiDAR derived information approaches 80% when classifying forests cover at the finest scale of 5 by 5m into 10 different types and reaches 87% when a coarser classification Into 6 forest types is considered (figure 4).  
  Address IRD, UMR AMAP, Montpellier, France  
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  Notes Cited By (since 1996): 1; Export Date: 21 October 2011; Source: Scopus; Language of Original Document: French; Correspondence Address: Vincent, G.; IRD, UMR AMAP, Kourou – BP 701 (CIRAD) 97387 Kourou cedex -Guyane, France Approved no  
  Call Number EcoFoG @ webmaster @ Serial 351  
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Author Staudt, K.; Serafimovich, A.; Siebicke, L.; Pyles, R.D.; Falge, E. url  openurl
  Title Vertical structure of evapotranspiration at a forest site (a case study) Type Journal Article
  Year 2011 Publication Agricultural and Forest Meteorology Abbreviated Journal Agric. For. Meterol.  
  Volume 151 Issue 6 Pages 709-729  
  Keywords Eddy-covariance; Evapotranspiration; In-canopy profiles; Model; Picea abies L.; Sap flux; coniferous forest; ecosystem modeling; eddy covariance; evapotranspiration; forest canopy; sap flow; Fichtelgebirge; Germany; Picea abies  
  Abstract The components of ecosystem evapotranspiration of a Norway spruce forest (Picea abies L.) as well as the vertical structure of canopy evapotranspiration were analyzed with a combination of measurements and models for a case study of 5 days in September 2007. Eddy-covariance and sap flux measurements were performed at several heights within the canopy at the FLUXNET site Waldstein-Weidenbrunnen (DE-Bay) in the Fichtelgebirge mountains in Germany. Within and above canopy fluxes were simulated with two stand-scale models, the 1D multilayer model ACASA that includes a third-order turbulence closure and the 3D model STANDFLUX. The soil and understory evapotranspiration captured with the eddy-covariance system in the trunk space constituted 10% of ecosystem evapotranspiration measured with the eddy-covariance system above the canopy. A comparison of transpiration measured with the sap flux technique and inferred from below and above canopy eddy-covariance systems revealed higher estimates from eddy-covariance measurements than for sap flux measurements. The relative influences of possible sources of this mismatch, such as the assumption of negligible contribution of evaporation from intercepted water, and differences between the eddy-covariance flux footprint and the area used for scaling sap flux measurements, were discussed. Ecosystem evapotranspiration as well as canopy transpiration simulated with the two models captured the dynamics of the measurements well, but slightly underestimated eddy-covariance values. Profile measurements and models also gave us the chance to assess in-canopy profiles of canopy evapotranspiration and the contributions of in-canopy layers. For daytime and a coupled or partly coupled canopy, mean simulated profiles of both models agreed well with eddy-covariance measurements, with a similar performance of the ACASA and the STANDFLUX model. Both models underestimated profiles for nighttime and decoupled conditions. During daytime, the upper half of the canopy contributed approximately 80% to canopy evapotranspiration, whereas during nighttime the contribution shifted to lower parts of the canopy. © 2010 Elsevier B.V.  
  Address Max Planck Institute for Chemistry, Biogeochemistry Department, Joh.-J.-Becherweg 27, 55128 Mainz, Germany  
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  Notes Cited By (since 1996): 3; Export Date: 21 October 2011; Source: Scopus; Coden: Afmee; doi: 10.1016/j.agrformet.2010.10.009; Language of Original Document: English; Correspondence Address: Staudt, K.; University of Bayreuth, Department of Micrometeorology, 95440 Bayreuth, Germany; email: katharina.staudt@uni-bayreuth.de Approved no  
  Call Number EcoFoG @ webmaster @ Serial 349  
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