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Auteur David A. Coomes |
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Good things take time : Diversity effects on tree growth shift from negative to positive during stand development in boreal forests / Tommaso Jucker in Journal of ecology, vol 108 n° 6 (November 2020)
[article]
Titre : Good things take time : Diversity effects on tree growth shift from negative to positive during stand development in boreal forests Type de document : Article/Communication Auteurs : Tommaso Jucker, Auteur ; Julia Koricheva, Auteur ; Leena Finer, Auteur ; Olivier Bouriaud , Auteur ; Giovanni Lacopetti, Auteur ; David A. Coomes, Auteur Année de publication : 2020 Projets : 3-projet - voir note / Article en page(s) : pp 2198 - 2211 Note générale : bibliographie
Natural Environment Research Council. Grant Number: NE/S01537X/1 - European Union Seventh Framework Programme. Grant Numbers: 265171, FP7/2007‐2013Langues : Anglais (eng) Descripteur : [Termes IGN] biodiversité végétale
[Termes IGN] cerne
[Termes IGN] croissance des arbres
[Termes IGN] écosystème forestier
[Termes IGN] Finlande
[Termes IGN] forêt boréale
[Termes IGN] production primaire brute
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Long‐term grassland biodiversity experiments have shown that diversity effects on productivity tend to strengthen through time, as complementarity among coexisting species increases. But it remains less clear whether this pattern also holds for other ecosystems such as forests, and if so why. Here we explore whether diversity effects on tree growth change predictably during stand development in Finland's boreal forests. Using tree ring records from mature forests, we tested whether diameter growth trajectories of dominant tree species growing in mixture differed from those in monoculture. We then compared these results with data from the world's longest running tree diversity experiment, where the same combinations of species sampled in mature forests were planted in 1999. We found that diversity effects on tree growth strengthened progressively through time, only becoming significantly positive around 20 years after seedling establishment. This shift coincided with the period in which canopy closure occurs in these forests, at which time trees begin to interact and compete above‐ground. These temporal trends were remarkably consistent across different tree species sampled in mature forests, and broadly matched growth responses observed in the much younger experimental plots. Synthesis. Our results mirror those from grassland ecosystems and suggest that canopy closure is a key phase for promoting niche complementarity in diverse tree communities. They also provide a series of testable hypotheses for the growing number of tree diversity experiments that have been established in recent years. Numéro de notice : A2020-360 Affiliation des auteurs : LIF+Ext (2020- ) Thématique : BIODIVERSITE/FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/1365-2745.13464 Date de publication en ligne : 06/07/2020 En ligne : https://doi.org/10.1111/1365-2745.13464 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96961
in Journal of ecology > vol 108 n° 6 (November 2020) . - pp 2198 - 2211[article]How do trees respond to species mixing in experimental compared to observational studies? / Stephan Kambach in Ecology and evolution, vol 9 n° 19 (October 2019)
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Titre : How do trees respond to species mixing in experimental compared to observational studies? Type de document : Article/Communication Auteurs : Stephan Kambach, Auteur ; Eric Allan, Auteur ; Simon Bilodeau‐Gauthier, Auteur ; David A. Coomes, Auteur ; Josephine Haase, Auteur ; Tommaso Jucker, Auteur ; Georges Kunstler, Auteur ; Sandra Müller, Auteur ; Charles Nock, Auteur ; Alain Paquette, Auteur ; Fons van der plas, Auteur ; Sophie Ratcliffe, Auteur ; Fabian Roger, Auteur ; Paloma Ruiz-Benito, Auteur ; Michael Scherer‐Lorenzen, Auteur ; Harald Auge, Auteur ; Olivier Bouriaud , Auteur ; et al., Auteur Année de publication : 2019 Projets : 3-projet - voir note / Article en page(s) : pp 11254 - 11265 Note générale : bibliographie
This paper is a joint effort of the working group sFundivEurope kindly supported by sDiv, the Synthesis Centre of the German Centre for Integrative Biodiversity Research (iDiv) Halle‐Jena‐Leipzig, funded by the German Research Foundation (FZT 118). The FunDivEUROPE project received funding from the European Union's Seventh Programme (FP7/2007–2013) under grant agreement No. 26517.Langues : Anglais (eng) Descripteur : [Termes IGN] biodiversité
[Termes IGN] croissance des arbres
[Termes IGN] diamètre des arbres
[Termes IGN] forêt de production
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] peuplement mélangé
[Termes IGN] productivité
[Vedettes matières IGN] SylvicultureRésumé : (auteur) For decades, ecologists have investigated the effects of tree species diversity on tree productivity at different scales and with different approaches ranging from observational to experimental study designs. Using data from five European national forest inventories (16,773 plots), six tree species diversity experiments (584 plots), and six networks of comparative plots (169 plots), we tested whether tree species growth responses to species mixing are consistent and therefore transferrable between those different research approaches. Our results confirm the general positive effect of tree species mixing on species growth (16% on average) but we found no consistency in species‐specific responses to mixing between any of the three approaches, even after restricting comparisons to only those plots that shared similar mixtures compositions and forest types. These findings highlight the necessity to consider results from different research approaches when selecting species mixtures that should maximize positive forest biodiversity and functioning relationships. Numéro de notice : A2019-616 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1002/ece3.5627 Date de publication en ligne : 10/09/2019 En ligne : https://doi.org/10.1002/ece3.5627 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95342
in Ecology and evolution > vol 9 n° 19 (October 2019) . - pp 11254 - 11265[article]A simple approach to forest structure classification using airborne laser scanning that can be adopted across bioregions / Syed Adnan in Forest ecology and management, vol 433 (15 February 2019)
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Titre : A simple approach to forest structure classification using airborne laser scanning that can be adopted across bioregions Type de document : Article/Communication Auteurs : Syed Adnan, Auteur ; Matti Maltamo, Auteur ; David A. Coomes, Auteur ; Antonio Garcia-Abril, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 111 - 121 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] canopée
[Termes IGN] classification ascendante hiérarchique
[Termes IGN] classification barycentrique
[Termes IGN] classification et arbre de régression
[Termes IGN] coefficient de Gini
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] dynamique de la végétation
[Termes IGN] écorégion
[Termes IGN] hétérogénéité environnementale
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Pinophyta
[Termes IGN] structure d'un peuplement forestierRésumé : (auteur) Reliable assessment of forest structural types (FSTs) aids sustainable forest management. We developed a methodology for the identification of FSTs using airborne laser scanning (ALS), and demonstrate its generality by applying it to forests from Boreal, Mediterranean and Atlantic biogeographical regions. First, hierarchal clustering analysis (HCA) was applied and clusters (FSTs) were determined in coniferous and deciduous forests using four forest structural variables obtained from forest inventory data – quadratic mean diameter , Gini coefficient , basal area larger than mean and density of stems –. Then, classification and regression tree analysis (CART) were used to extract the empirical threshold values for discriminating those clusters. Based on the classification trees, and were the most important variables in the identification of FSTs. Lower, medium and high values of and characterize single storey FSTs, multi-layered FSTs and exponentially decreasing size distributions (reversed J), respectively. Within each of these main FST groups, we also identified young/mature and sparse/dense subtypes using and . Then we used similar structural predictors derived from ALS – maximum height (), L-coefficient of variation (), L-skewness (), and percentage of penetration (), – and a nearest neighbour method to predict the FSTs. We obtained a greater overall accuracy in deciduous forest (0.87) as compared to the coniferous forest (0.72). Our methodology proves the usefulness of ALS data for structural heterogeneity assessment of forests across biogeographical regions. Our simple two-tier approach to FST classification paves the way toward transnational assessments of forest structure across bioregions. Numéro de notice : A2019-007 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2018.10.057 Date de publication en ligne : 03/11/2018 En ligne : https://doi.org/10.1016/j.foreco.2018.10.057 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91600
in Forest ecology and management > vol 433 (15 February 2019) . - pp 111 - 121[article]Above ground biomass estimation in an African tropical forest with lidar and hyperspectral data / Gaia Vaglio Laurin in ISPRS Journal of photogrammetry and remote sensing, vol 89 (March 2014)
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Titre : Above ground biomass estimation in an African tropical forest with lidar and hyperspectral data Type de document : Article/Communication Auteurs : Gaia Vaglio Laurin, Auteur ; Qi Chen, Auteur ; Jeremy A. Lindsell, Auteur ; David A. Coomes, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 49 - 58 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Afrique tropicale
[Termes IGN] bilan du carbone
[Termes IGN] biomasse
[Termes IGN] données lidar
[Termes IGN] forêt tropicale
[Termes IGN] image hyperspectrale
[Termes IGN] modélisation de la forêtRésumé : (Auteur) The estimation of above ground biomass in forests is critical for carbon cycle modeling and climate change mitigation programs. Small footprint lidar provides accurate biomass estimates, but its application in tropical forests has been limited, particularly in Africa. Hyperspectral data record canopy spectral information that is potentially related to forest biomass. To assess lidar ability to retrieve biomass in an African forest and the usefulness of including hyperspectral information, we modeled biomass using small footprint lidar metrics as well as airborne hyperspectral bands and derived vegetation indexes. Partial Least Square Regression (PLSR) was adopted to cope with multiple inputs and multicollinearity issues; the Variable of Importance in the Projection was calculated to evaluate importance of individual predictors for biomass. Our findings showed that the integration of hyperspectral bands (R2 = 0.70) improved the model based on lidar alone (R2 = 0.64), this encouraging result call for additional research to clarify the possible role of hyperspectral data in tropical regions. Replacing the hyperspectral bands with vegetation indexes resulted in a smaller improvement (R2 = 0.67). Hyperspectral bands had limited predictive power (R2 = 0.36) when used alone. This analysis proves the efficiency of using PLSR with small-footprint lidar and high resolution hyperspectral data in tropical forests for biomass estimation. Results also suggest that high quality ground truth data is crucial for lidar-based AGB estimates in tropical African forests, especially if airborne lidar is used as an intermediate step of upscaling field-measured AGB to a larger area. Numéro de notice : A2014-124 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2014.01.001 En ligne : https://doi.org/10.1016/j.isprsjprs.2014.01.001 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=33029
in ISPRS Journal of photogrammetry and remote sensing > vol 89 (March 2014) . - pp 49 - 58[article]Exemplaires(1)
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