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Effects of urban tree canopy loss on land surface temperature magnitude and timing / Arthur Elmes in ISPRS Journal of photogrammetry and remote sensing, vol 128 (June 2017)
[article]
Titre : Effects of urban tree canopy loss on land surface temperature magnitude and timing Type de document : Article/Communication Auteurs : Arthur Elmes, Auteur ; John Rogan, Auteur ; Christopher Williams, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 338 - 353 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse diachronique
[Termes IGN] arbre urbain
[Termes IGN] densité de la végétation
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] étude d'impact
[Termes IGN] ilot thermique urbain
[Termes IGN] image Worldview
[Termes IGN] Massachusetts (Etats-Unis)
[Termes IGN] température de surface
[Termes IGN] variation saisonnière
[Termes IGN] zone urbaineRésumé : (Auteur) Urban Tree Canopy (UTC) plays an important role in moderating the Surface Urban Heat Island (SUHI) effect, which poses threats to human health due to substantially increased temperatures relative to rural areas. UTC coverage is associated with reduced urban temperatures, and therefore benefits both human health and reducing energy use in cities. Measurement of this relationship relies on accurate, fine spatial resolution UTC mapping, and on time series analysis of Land Surface Temperatures (LST). The City of Worcester, Massachusetts underwent extensive UTC loss and gain during the relatively brief period from 2008 to 2015, providing a natural experiment to measure the UTC/LST relationship. This paper consists of two elements to this end. First, it presents methods to map UTC in urban and suburban locations at fine spatial resolution (∼0.5 m) using image segmentation of a fused Lidar/WorldView-2 dataset, in order to show UTC change over time. Second, the areas of UTC change are used to explore changes in LST magnitude and seasonal variability using a time series of all available Landsat data for the study area over the eight-year period from 2007 to 2015. Fractional UTC change per unit area was determined using fine resolution UTC maps for 2008, 2010, and 2015, covering the period of large-scale tree loss and subsequent planting. LST changes were measured across a series of net UTC change bins, providing a relationship between UTC net change and LST trend. LST was analyzed for both monotonic trends over time and changes to seasonal magnitude and timing, using Theil-Sen slopes and Seasonal Trend Analysis (STA), respectively. The largest magnitudes of UTC loss occurred in residential neighborhoods, causing increased exposure of impervious (road) and pervious (grass) surfaces. Net UTC loss showed higher monotonic increases in LST than persistence and gain areas. STA indicated that net UTC loss was associated greater difference between 2008 and 2015 seasonal temperature curves than persistence areas, and also larger peak LST values, with peak increases ranging from 1 to 6 °C. Timing of summer warm period was extended in UTC loss areas by up to 15 days. UTC gain provided moderate LST mitigation, with lower monotonic trends, lower peak temperatures, and smaller seasonal curve changes than both persistence and loss locations. This study shows that urban trees mitigate the magnitude and timing of the surface urban heat island effect, even in suburban areas with less proportional impervious coverage than the dense urban areas traditionally associated with SUHI. Trees can therefore be seen as an effective means of offsetting the energy-intensive urban heat island effect. Numéro de notice : A2017-338 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2017.04.011 En ligne : https://doi.org/10.1016/j.isprsjprs.2017.04.011 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85506
in ISPRS Journal of photogrammetry and remote sensing > vol 128 (June 2017) . - pp 338 - 353[article]Exemplaires(3)
Code-barres Cote Support Localisation Section Disponibilité 081-2017061 RAB Revue Centre de documentation En réserve L003 Disponible 081-2017063 DEP-EXM Revue LASTIG Dépôt en unité Exclu du prêt 081-2017062 DEP-EAF Revue Nancy Dépôt en unité Exclu du prêt Forest modelling: the gamma shape mixture model and simulation of tree diameter distributions / Rafał Podlaski in Annals of Forest Science, vol 74 n° 2 (June 2017)
[article]
Titre : Forest modelling: the gamma shape mixture model and simulation of tree diameter distributions Type de document : Article/Communication Auteurs : Rafał Podlaski, Auteur Année de publication : 2017 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] arbre (flore)
[Termes IGN] densité de la végétation
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] diamètre des arbres
[Termes IGN] dynamique de la végétation
[Termes IGN] estimation par noyau
[Termes IGN] modèle de simulation
[Termes IGN] modélisation de la forêt
[Termes IGN] surveillance de la végétationRésumé : (auteur) Key message: New types of distribution functions are needed to model the dynamics of stands where important age classes are represented by few trees. In this study, the gamma shape mixture model and two simulation methods were used for generating tree diameter data.
• Context: To analyse forest dynamics, it is necessary to know distribution of the characteristics (mainly tree diameters) of trees forming particular developmental phases. In many forest inventories, the measurement of large diameter at breast height (DBH) samples is practically impossible. In this case, DBH distributions can be generated using theoretical models.
• Aims: The aim of this study was to assess the precision of the approximation of empirical DBH data using the gamma shape mixture (GSM) model and kernel density estimation. The strengths and weaknesses of the two simulation methods were presented and discussed.
• Methods: The GSM model was adopted to approximate empirical DBH data collected in 20 near-natural stands. Two simulation methods were used: (a) the procedure based on a multimodal distribution and gamma random numbers (MDGR procedure) and (b) MCMC techniques with Metropolis–Hastings sampling (MH method).
• Results: The GSM model precisely fitted the investigated DBH distributions. The MDGR procedure was slightly more precise than the MH method, especially in the case of the samples of 250 DBHs. The level of homogeneity within the drawn DBH sets was similar for all samples.
• Conclusion: The GSM model is very flexible. The DBH random variates, generated with the use of analysed procedures, represented all tree generations being significant from a biological point of view.Numéro de notice : A2017-109 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-017-0629-y Date de publication en ligne : 03/04/2017 En ligne : https://doi.org/10.1007/s13595-017-0629-y Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84500
in Annals of Forest Science > vol 74 n° 2 (June 2017)[article]Radial growth resilience of sessile oak after drought is affected by site water status, stand density, and social status / Raphaël Trouvé in Trees, vol 31 n° 2 (April 2017)
[article]
Titre : Radial growth resilience of sessile oak after drought is affected by site water status, stand density, and social status Type de document : Article/Communication Auteurs : Raphaël Trouvé, Auteur ; Jean-Daniel Bontemps , Auteur ; Catherine Collet, Auteur ; Ingrid Seynave, Auteur ; François Lebourgeois, Auteur Année de publication : 2017 Projets : ORACLE/Changements Environnementaux Planétaires & Sociétés (CEP&S) / Noblet-Ducoudré, Nathalie de Article en page(s) : pp 517 - 529 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] croissance des arbres
[Termes IGN] densité de la végétation
[Termes IGN] Quercus sessiliflora
[Termes IGN] résilience écologique
[Termes IGN] sécheresseRésumé : (auteur) Ongoing climate change will drive more frequent drought events in the future, with potential impacts on tree community structure and functioning. Growth responses of tree communities may depend on their past water status and on competition pressure. We investigated the effects of site water status, population density, and tree social status on tree growth resistance and resilience following the severe drought of 1976 in even-aged stands of sessile oak (Quercus petraea). We used retrospective growth data collected in permanent plots experiencing contrasted climatic and stand density conditions. We used boosted regression trees to calibrate a tree growth model over 1960–1975, which was then used to provide a baseline of expected tree growth following 1976. Growth dynamics during and after 1976 was examined using the ratio between observed and expected growths over 1976–1983. Tree radial growth was on average 0.6 times its expected values in 1976 and was still 0.63 times its expected value in 1977. Despite experiencing higher summer soil water deficit in 1976, trees growing in drier sites exhibited remarkably faster growth recovery than those in moister sites. Suppressed trees grown in higher density stands recovered their normal growth rate slower than dominant trees. Forest growth is evidenced to be more vulnerable to drought in moister than in drier sites. Competitive pressures also alter tree capacity to recover from a severe drought, accelerating suppression of smaller trees in high-density stands. These results highlight the role of acclimation and selection processes in tree community responses to present and future climates. Numéro de notice : A2017-874 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00468-016-1479-1 Date de publication en ligne : 21/10/2016 En ligne : https://doi.org/10.1007/s00468-016-1479-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90996
in Trees > vol 31 n° 2 (April 2017) . - pp 517 - 529[article]Characterizing vegetation canopy structure using airborne remote sensing data / Debsunder Dutta in IEEE Transactions on geoscience and remote sensing, vol 55 n° 2 (February 2017)
[article]
Titre : Characterizing vegetation canopy structure using airborne remote sensing data Type de document : Article/Communication Auteurs : Debsunder Dutta, Auteur ; Kunxuan Wang, Auteur ; Esther Lee, Auteur Année de publication : 2017 Article en page(s) : pp 1160 - 1178 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] canopée
[Termes IGN] densité de la végétation
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] feuille (végétation)
[Termes IGN] forêt ripicole
[Termes IGN] image aérienne
[Termes IGN] image hyperspectrale
[Termes IGN] semis de points
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] voxelRésumé : (Auteur) Vegetation canopy structure plays an important role in the partitioning of incident solar radiation, photosynthesis, transpiration, and other scalar fluxes. The vertical foliage distribution of the plant canopy is represented by leaf area density (LAD), which is defined as the one-sided leaf area per unit volume. Airborne light detection and ranging (LiDAR) offers the possibility to characterize the 3-D variation of LAD over space, which still remains a challenge to estimate. Moreover, the low density of point cloud data generally offered by airborne LiDAR may be insufficient for accurate LAD estimation in dense overlapping forest canopies. We develop a method for the estimation of the LAD profile using a combination of airborne LiDAR and hyperspectral data using a feature-based data fusion approach. After identifying vegetation species using hyperspectral data, point cloud LiDAR data is used in a “tree-shaped” voxel approach to characterize the LAD of trees in a riparian forest setting. We also propose a set of relationships on simple geometry of overlap for the construction of tree shaped voxels. In a forest setting with overlapping canopies, the results indicate that the tree-shaped voxels are better able to attribute the LAD to the upper and middle parts of the overall canopy as well as individual tall and short trees compared with traditional cylindrical voxels. Numéro de notice : A2017-147 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2016.2620478 En ligne : http://dx.doi.org/10.1109/TGRS.2016.2620478 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=84635
in IEEE Transactions on geoscience and remote sensing > vol 55 n° 2 (February 2017) . - pp 1160 - 1178[article]Forest diversity promotes individual tree growth in central European forest stands / Juliette Chamagne in Journal of applied ecology, vol 54 n° 1 (February 2017)
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Titre : Forest diversity promotes individual tree growth in central European forest stands Type de document : Article/Communication Auteurs : Juliette Chamagne, Auteur ; Matteo Tanadini, Auteur ; David Frank, Auteur ; Radim Matula, Auteur ; et al., Auteur Année de publication : 2017 Article en page(s) : pp 71 - 79 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] biodiversité
[Termes IGN] croissance des arbres
[Termes IGN] dendrochronologie
[Termes IGN] densité de la végétation
[Termes IGN] Europe centrale
[Termes IGN] forêt
[Termes IGN] peuplement forestier
[Termes IGN] service écosystémique
[Vedettes matières IGN] SylvicultureRésumé : (Auteur) Most experimental evidence on the relationship between biodiversity and ecosystem functioning comes from ecosystems with fast‐growing plants, such as grasslands. Although forests provide essential ecological services, they have been less well investigated. We used dendrochronology to compare the tree radial growth rates of four important timber species in replicated, spatially mapped stands that differed in tree composition and diversity within a central European managed forest. Growth rates differed among species but were largely unaffected by the density of neighbouring trees. Increasing stand diversity enhanced individual growth rates, after accounting for the effects of tree density and size. These increases were statistically indistinguishable among the four species. In contrast, the effects of stand and neighbourhood species composition on growth rates were non‐significant. Policy implications. Our study of long‐established central European forest stands revealed levels of tree diversity can be increased in managed forests, with the potential for modest increases in tree growth rates. These results suggest that in addition to the biodiversity and risk mitigation benefits associated with shifting practices away from monoculture management, increased carbon sequestration and yields in mature forests are likely to be realized. Our results suggest that it is possible to increase forest diversity with little or no costs to production and even with the potential for modest increases in tree growth rates. Numéro de notice : A2017-900 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/1365-2664.12783 Date de publication en ligne : 17/01/2017 En ligne : https://doi.org/10.1111/1365-2664.12783 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92957
in Journal of applied ecology > vol 54 n° 1 (February 2017) . - pp 71 - 79[article]Caractérisation de la végétation de Rennes Métropole par relevé LiDAR en vue de sa modélisation / Clément Doceul (2017)PermalinkEstimating the solar transmittance of urban trees using airborne LiDAR and radiative transfer simulation / Haruki Oshio in IEEE Transactions on geoscience and remote sensing, vol 54 n° 9 (September 2016)PermalinkGlobal sensitivity analysis of the L-MEB model for retrieving soil moisture / Zengyan Wang in IEEE Transactions on geoscience and remote sensing, vol 54 n° 5 (May 2016)PermalinkGéo-poppy, un serveur web SIG portable pour le recueil de données terrain / Julien Ancelin in Géomatique expert, n° 109 (mars - avril 2016)PermalinkMicrowave unmixing with video segmentation for inferring broadleaf and needleleaf brightness temperatures and abundances from mixed forest observations / Lingjia Gu in IEEE Transactions on geoscience and remote sensing, vol 54 n° 1 (January 2016)PermalinkNeighborhood greenspace and health in a large urban center / Omid Kardan in Scientific reports, vol 5 (2015)PermalinkDo competition-density rule and self-thinning rule agree? / Sonja Vospernik in Annals of Forest Science, vol 72 n° 3 (May 2015)PermalinkEffect of host tree density and apparency on the probability of attack by the pine processionary moth / Margot Regolini in Forest ecology and management, vol 334 ([15/12/2014])PermalinkA comprehensive framework of forest stand property-density relationships: perspectives for plant population ecology and forest management / James N. Long in Annals of Forest Science, vol 71 n° 3 (April - May 2014)PermalinkAn improved dark object method to retrieve 500 m-resolution AOT (Aerosol Optical Thickness) image from MODIS data: A case study in the Pearl River Delta area, China / Lili Li in ISPRS Journal of photogrammetry and remote sensing, vol 89 (March 2014)Permalink