Centre de documentation
scientifique

About tree height measurement: Theoretical and practical issues for uncertainty quantification and mapping / Samuele De petris in Forests, vol 13 n° 7 (July 2022)  

Public [article]  inForests > vol 13 n° 7 (July 2022) . - n°969 Titre : About tree height measurement: Theoretical and practical issues for uncertainty quantification and mapping Type de document : Article/Communication Auteurs : Samuele De petris, Auteur ; Philippo Sarvia, Auteur ; Enrico Borgogno Mondino, Auteur Année de publication : 2022 Article en page(s) : n°969 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse de sensibilité [Termes IGN] biome [Termes IGN] carte forestière [Termes IGN] Google Earth Engine [Termes IGN] hauteur des arbres [Termes IGN] incertitude de mesurage [Termes IGN] modèle de simulation [Termes IGN] pente [Termes IGN] statistiques [Termes IGN] variance [Vedettes matières IGN] Foresterie Résumé : (auteur) Forest height is a fundamental parameter in forestry. Tree height is widely used to assess a site’s productivity both in forest ecology research and forest management. Thus, a precise height measure represents a necessary step for the estimation of carbon storage at the local, national, and global scales. In this context, error in height measurement necessarily affects the accuracy of related estimates. Ordinarily, forest height is surveyed by ground sampling adopting hypsometers. The latter suffers from many errors mainly related to the correct tree apex identification (not always well visible in dense stands) and to the measurement process itself. In this work, a statistically based operative method for estimating height measurement uncertainty (σH) was proposed using the variance propagation law. Some simulations were performed involving several combinations of terrain slope, tree height, and survey distances by modelling the σH behaviour and its sensitivity to such parameters. Results proved that σH could vary between 0.5 m and up to 20 m (worst case). Sensitivity analysis shows that terrain slopes and distance poorly affect σH, while angles are the main drivers of height uncertainty. Finally, to give a practical example of such deductions, tree height uncertainty was mapped at the global scale using Google Earth Engine and summarized per forest biomes. Results proved that tropical biomes have higher uncertainty (from 1 m to 4 m) while shrublands and tundra have the lowest (under 1 m). Numéro de notice : A2022-546 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.3390/f13070969 Date de publication en ligne : 22/06/2022 En ligne : https://doi.org/10.3390/f13070969 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=101131 [article]

Assessing the agreement of ICESat-2 terrain and canopy height with airborne lidar over US ecozones / Lonesome Malambo in Remote sensing of environment, vol 266 (December 2021)  

Public [article]  inRemote sensing of environment > vol 266 (December 2021) . - n° 112711 Titre : Assessing the agreement of ICESat-2 terrain and canopy height with airborne lidar over US ecozones Type de document : Article/Communication Auteurs : Lonesome Malambo, Auteur ; Sorin C. Popescu, Auteur Année de publication : 2021 Article en page(s) : n° 112711 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes IGN] biome [Termes IGN] canopée [Termes IGN] données altimétriques [Termes IGN] données ICEsat [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] écorégion [Termes IGN] Etats-Unis [Termes IGN] hauteur des arbres [Termes IGN] photon [Termes IGN] semis de points [Termes IGN] télémétrie laser aéroporté Résumé : (auteur) Despite its critical importance to carbon storage modeling, forest vertical structure remains poorly characterized over large areas. Canopy height estimates from current satellite missions such as ICESat-2 (Ice, Cloud, and land Elevation Satellite-2) offer promise to close this knowledge gap, but their validation is critically important to inform their measurement uncertainties and scientific utility. Using existing airborne laser scanning (ALS) data, the agreement of a variety of terrain and aboveground canopy height metrics including summary height statistics and percentiles, from ICESat-2’ Land, Water and Vegetation Elevation product (ATL08) product was assessed in 12 sites across six major biomes in the United States. The agreement between ATL08 and ALS heights was assessed using the mean bias (Bias, ATL08 – ALS), the mean absolute error (MAE) and their percent equivalents, percent bias (pBias) and percent MAE (pMAE), respectively. In general, the agreement between ATL08 and ALS terrain heights was high (Bias 0.18 m, pBias 0.1%) while canopy heights showed lower agreement (Bias −1.71 m, pBias −15.9%). Analyses by biome, time of acquisition and beam strength of the ICESat-2 photon data also showed generally higher agreement for ATL08 terrain than canopy heights. Analyses also showed the performance of ATL08 heights varied with canopy cover with ATL08 terrain heights showing the best agreement when canopy cover was between 40 and 70% while the best performance for ATL08 canopy heights was observed when canopy cover was greater than 80%. This observation, coupled with analyses by biome, indicate that ATL08 canopy heights are more suitable in relatively dense canopy environments such as conifer and broadleaf forests than relatively sparse environments such a temperate grassland and Savannas. Higher level canopy height percentiles (95th and 98th) showed higher agreement (mean Bias −12.5%) with ALS heights than lower percentiles (minimum, 25th, mean pBias ~39.2%). These findings indicate that ATL08 canopy heights show more promise for routine canopy height characterization using the 95th and 98% percentiles but is limited in characterizing intermediate vertical structure. The observed performance differences between ATL08 terrain and canopy heights are attributed to differences in photon sampling rates over terrain and canopy surfaces which, compounded with background noise in ICESat-2 photon data, led to different effectiveness for ATL08 processing routines in filtering terrain and off-terrain points. This assessment of the impact of a variety of factors provides the vegetation community with an understanding of the capabilities and limitations of height estimates from the ICESat-2 ATL08 product. Numéro de notice : A2021-922 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1016/j.rse.2021.112711 Date de publication en ligne : 24/09/2021 En ligne : https://doi.org/10.1016/j.rse.2021.112711 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99277 [article]

Drivers and implications of dominant and rare tree species in global forests / Iris Hordijk (2021)  

Public Titre : Drivers and implications of dominant and rare tree species in global forests Type de document : Thèse/HDR Auteurs : Iris Hordijk, Auteur Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Année de publication : 2021 Note générale : bibliographie Thesis submitted to attain the degree of Doctor of Sciences of ETH Zurich Langues : Anglais (eng) Descripteur : [Termes IGN] âge du peuplement forestier [Termes IGN] biodiversité végétale [Termes IGN] biome [Termes IGN] écosystème forestier [Termes IGN] espèce végétale [Termes IGN] extinction (biologie) [Termes IGN] forêt boréale [Termes IGN] forêt tempérée [Termes IGN] forêt tropicale [Termes IGN] habitat (nature) [Termes IGN] peuplement forestier [Termes IGN] plante menacée [Termes IGN] productivité biologique [Termes IGN] richesse floristique [Termes IGN] service écosystémique [Vedettes matières IGN] Inventaire forestier Index. décimale : THESE Thèses et HDR Résumé : (auteur) Forests provide crucial ecosystem functions and services for the earth system and humanity. Due to ongoing deforestation and forest degradation, these ecosystems are increasingly fragmented and disturbed, significantly changing tree species composition within the forest. Most plant communities are comprised of a few dominant species that are numerically abundant, and many rare species, each of which exist at low abundance. Given their differences in abundance and characteristics, the loss of dominant and rare species have distinct impacts on ecosystem functioning. Decreasing abundances of dominant species typically have larger immediate impacts on overall ecosystem processes (e.g. productivity), while a decline in abundance of rare species can lead to the loss of key functions and overall multifunctionality, and can ultimately drive species extinctions. Despite their unique role in the ecosystem, it remains unclear what drives species to become dominant or rare, how threatened locally dominant and rare species are, and what the effect of species abundance on ecosystem function is across large environmental gradients in our global forests. The aim of this thesis is to explore the drivers of tree species abundance, and evaluate the effect of relative tree species abundance on forest productivity. Specifically, the three chapters of this thesis aimed to identify at a global scale the 1) patterns, drivers, and threats to dominant and rare tree species, 2) differences in trait values and trait diversity that differentiate the functional contributions of dominant and rare tree species, and 3) how evenness (the relative species abundances in the community) mediates the relationship between tree species richness and forest productivity in forests. In this thesis I answered these research questions by analyzing a global dataset of forest composition, which enabled me to describe broad-scale ecological patterns and to test general ecological laws. Note de contenu : General introduction 1- Patterns, drivers and threats to dominant and rare tree species worldwide 2- Trait diversity of dominant and rare tree species in global forests: a habitat filtering perspective 3- Evenness mediates the global relationship between forest productivity and richness Synthesis Numéro de notice : 28690 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Thèse étrangère Note de thèse : PhD Thesis : Sciences : ETH Zurich 2021 DOI : sans En ligne : https://www.research-collection.ethz.ch/handle/20.500.11850/520710 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=100131

Les impacts spatiaux du changement climatique / Denis Mercier (2021)

Public Titre : Les impacts spatiaux du changement climatique Type de document : Monographie Auteurs : Denis Mercier, Éditeur scientifique Editeur : Londres : ISTE Editions Année de publication : 2021 Importance : 334 p. Format : 16 x 24 cm ISBN/ISSN/EAN : 978-1-78948-009-2 Note générale : Bibliographie Langues : Français (fre) Descripteur : [Vedettes matières IGN] Géomatique [Termes IGN] Amazonie [Termes IGN] Asie centrale [Termes IGN] biome [Termes IGN] changement climatique [Termes IGN] cours d'eau [Termes IGN] cryosphère [Termes IGN] faune [Termes IGN] montée du niveau de la mer [Termes IGN] sécheresse [Termes IGN] viticulture Index. décimale : 37.00 Géomatique - information géographique - infrastructure de données Résumé : (Editeur) Depuis quelques années, le changement climatique est au centre des préoccupations avec des conséquences visibles et fortement médiatisées comme la fonte de la banquise arctique, la fonte des glaciers de montagne, l’élévation du niveau de la mer ou la submersion des littoraux bas lors des tempêtes des latitudes moyennes et des cyclones tropicaux. Cet ouvrage expose une revue des impacts spatiaux du changement climatique contemporain en privilégiant une approche multiscalaire et systémique. Au-delà des faits (élévation de la température, modification de la distribution spatiale des précipitations, fonte de la cryosphère marine et terrestre, modifications des régimes hydrologiques aux hautes et moyennes latitudes, etc.), il analyse également les conséquences géopolitiques en Arctique et en Asie centrale, les changements sur les cultures méditerranéennes et sur la viticulture à l’échelle mondiale, ainsi que les impacts sur la distribution du vivant (forêt amazonienne, grands biomes à l’échelle mondiale, oiseaux, etc.). Note de contenu : 1. Le changement climatique à différentes échelles temporelles et spatiales 2. Le changement climatique et la fonte de la cryosphère 3. Entre réchauffement et mondialisation, repenser l’Arctique au coeur d’un système d’enjeux 4. Des littoraux à la vulnérabilité accrue face à l’élévation du niveau de la mer 5. Les conséquences du changement climatique sur la cascade sédimentaire paraglaciaire 6. Les impacts spatiaux du changement climatique sur les environnements périglaciaires 7. Les impacts du changement climatique sur les dynamiques hydrologiques des milieux périglaciaires de hautes latitudes 8. Les impacts du changement climatique sur les cours d’eau des milieux tempérés 9. Les impacts spatiaux de la fonte des glaciers d’Asie centrale : vers une « guerre de l’eau » ? 10. Impact spatial du changement climatique sur les sécheresses hivernales en Méditerranée et ses conséquences sur l’agriculture 11. Les impacts spatiaux du changement climatique sur la viticulture dans le monde 12. Les changements climatiques en Amazonie, une approche multiscalaire 13. Les impacts du changement climatique sur la distribution des biomes 14. Les impacts spatiaux du changement climatique sur les oiseaux Numéro de notice : 26545 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/GEOMATIQUE Nature : Monographie DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97815

Quantification of cotton water consumption by remote sensing / Jefferson Vieira José in Geocarto international, vol 35 n° 16 ([01/12/2020])  

Public [article]  inGeocarto international > vol 35 n° 16 [01/12/2020] . - pp 1800 - 1813 Titre : Quantification of cotton water consumption by remote sensing Type de document : Article/Communication Auteurs : Jefferson Vieira José, Auteur ; Niclene Ponce Rodrigues de Oliveira, Auteur ; Tonny José Araújo da Silva, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 1800 - 1813 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale [Termes IGN] biome [Termes IGN] cultures irriguées [Termes IGN] évapotranspiration [Termes IGN] gestion de l'eau [Termes IGN] Gossypium (genre) [Termes IGN] image thermique [Termes IGN] irrigation [Termes IGN] Leaf Area Index [Termes IGN] Mato Grosso Résumé : (auteur) Quantifying crop water consumption is essential for water resource management. The objective was to estimate the current evapotranspiration (ETa) of the cotton crop (Gossypium hirsutum L.) in the rainfed system, as well as the components of the radiation and energy balance in the Cerrado biome conditions using orbital images and the SEBAL algorithm and validate the estimates of evapotranspiration (ET) using FAO guidelines for crop coefficient (K c) of the cotton crop. Research was carried out in the State of Mato Grosso, Brazil, in areas with three cotton cultivars. Images of the Operational Land Imager and Thermal Infrared Sensor sensors were used and ET estimation was made based on the SEBAL algorithm. Mean ETa in the cotton cycle was 3.5 mm dia−1 and the K c values ranged from 0.22 and 1.12, on average, in the smaller and larger leaf area, respectively. Numéro de notice : A2020-726 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2019.1583777 Date de publication en ligne : 18/03/2019 En ligne : https://doi.org/10.1080/10106049.2019.1583777 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96329 [article]

Effect of microsite quality and species composition on tree growth: A semi-empirical modeling approach / Carolina Mayoral in Forest ecology and management, vol 432 (15 January 2019)  

Permalink

How to calibrate historical aerial photographs : a change analysis of naturally dynamic boreal forest landscapes / Niko Kulha in Forests, vol 9 n° 10 (October 2018)  

Permalink

Testing the applicability of BIOME-BGC to simulate beech gross primary production in Europe using a new continental weather dataset / Marta Chiesi in Annals of Forest Science, vol 73 n° 3 (September 2016)  

Permalink

Regional dynamics of terrestrial vegetation productivity and climate feedbacks for territory of Ukraine / Dmytro Movchan in International journal of geographical information science IJGIS, vol 29 n° 8 (August 2015)  

Permalink

Two decades of normalized difference vegetation index changes in South America: identifying the imprint of global change / J.M. Paruelo in International Journal of Remote Sensing IJRS, vol 25 n° 14 (July 2004)  

Permalink