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Evaluating leaf chlorophyll content prediction from multispectral remote sensing data within a physically-based modelling framework / H. Croft in ISPRS Journal of photogrammetry and remote sensing, vol 102 (April 2015)
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Titre : Evaluating leaf chlorophyll content prediction from multispectral remote sensing data within a physically-based modelling framework Type de document : Article/Communication Auteurs : H. Croft, Auteur ; Jing M. Chen, Auteur ; Y. Zhang, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 85 - 95 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique
[Termes IGN] Acer saccharum
[Termes IGN] aiguille
[Termes IGN] image Landsat-TM
[Termes IGN] indice de stress
[Termes IGN] Leaf Area Index
[Termes IGN] modèle de transfert radiatif
[Termes IGN] Picea mariana
[Termes IGN] Pinus banksiana
[Termes IGN] Populus tremuloides
[Termes IGN] réflectance végétale
[Termes IGN] surveillance forestière
[Termes IGN] teneur en chlorophylle des feuillesRésumé : (auteur) Accurate modelling of leaf chlorophyll content over a range of spatial and temporal scales is central to monitoring vegetation stress and physiological condition, and vegetation response to different ecological, climatic and anthropogenic drivers. A process-based modelling approach can account for variation in other factors affecting canopy reflectance, providing a more accurate estimate of chlorophyll content across different vegetation species, time-frames, and broader spatial extents. However, physically-based modelling studies usually use hyperspectral data, neglecting a wealth of data from broadband and multispectral sources. In this study, we assessed the potential for using canopy (4-Scale) and leaf radiative transfer (PROSPECT4/5) models to estimate leaf chlorophyll content using canopy Landsat satellite data and simulated Landsat bands from leaf level hyperspectral reflectance data. Over 600 leaf samples were used to test the performance of PROSPECT for different vegetation species, including black spruce (Picea mariana), sugar maple (Acer saccharum), trembling aspen (Populus tremuloides) and jack pine (Pinus banksiana). At the leaf level, hyperspectral and simulated Landsat bands showed very similar results to laboratory measured chlorophyll (R2 = 0.77 and R2 = 0.75, respectively). Comparisons between PROSPECT4 modelled chlorophyll from simulated Landsat and hyperspectral spectra showed a very close correspondence (R2 = 0.97, root mean square error (RMSE) = 3.01 μg/cm2), as did simulated reflectance bands from other broadband and narrowband sensors (MODIS: R2 = 0.99, RMSE = 1.80 μg/cm2; MERIS: R2 = 0.97, RMSE = 2.50 μg/cm2 and SPOT5 HRG: R2 = 0.96, RMSE = 5.38 μg/cm2). Modelled leaf chlorophyll content from Landsat 5 TM canopy reflectance data, acquired from over 40 ground validation sites, demonstrated a strong relationship with measured leaf chlorophyll content (R2 = 0.78, RMSE = 8.73 μg/cm2, p Numéro de notice : A2015-691 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.01.008 En ligne : https://doi.org/10.1016/j.isprsjprs.2015.01.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78326
in ISPRS Journal of photogrammetry and remote sensing > vol 102 (April 2015) . - pp 85 - 95[article]Temporal stability of X-band single-pass InSAR heights in a spruce forest: effects of acquisition properties and season / Svein Solberg in IEEE Transactions on geoscience and remote sensing, vol 53 n° 3 (March 2015)
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Titre : Temporal stability of X-band single-pass InSAR heights in a spruce forest: effects of acquisition properties and season Type de document : Article/Communication Auteurs : Svein Solberg, Auteur ; Dan Johan Weydahl, Auteur ; Rasmus Astrup, Auteur Année de publication : 2015 Article en page(s) : pp 1607 - 1614 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] acquisition de données
[Termes IGN] bande X
[Termes IGN] biomasse
[Termes IGN] données météorologiques
[Termes IGN] forêt boréale
[Termes IGN] image radar moirée
[Termes IGN] image TanDEM-X
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] Norvège
[Termes IGN] Picea abies
[Termes IGN] stabilité dans le temps
[Termes IGN] surveillance forestièreRésumé : (Auteur) We investigated the stability of TanDEM-X interferometric synthetic aperture radar (InSAR) heights across eight repeated acquisitions. With InSAR height we mean the height above ground of the scattering phase center. We obtained InSAR heights by subtracting a digital terrain model generated from airborne laser scanning. The acquisitions varied in polarization, normal baseline, and season. The study area was a spruce forest in southeastern Norway. We established 179 field plots within 26 selected forest stands and obtained aboveground biomass (AGB) from field inventory. The InSAR heights were generally stable across the acquisitions as was the relationship between AGB and InSAR height, although systematic and random variations were noted. Two acquisitions had close-to-identical technical properties and weather conditions, and they produced close-to-identical InSAR heights. InSAR heights were fairly stable across a range in temperature and precipitation through spring, summer, and autumn, across a range in baseline values and for both HH and VV polarizations. However, a winter acquisition at temperatures of -7°C had much deeper penetration into the canopy and generated considerably lower InSAR heights and, hence, a very different relationship with biomass. Higher random errors were noted in a cross-pol data set due to lower backscatter and when the normal baseline was very small or very large. A height of ambiguity around 20-50 m appeared to be optimal. Interferometric X-band SAR can be used for monitoring coniferous boreal forests as long as the season and technical properties of the acquisition are kept within certain ranges. Numéro de notice : A2015-139 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2346473 Date de publication en ligne : 28/08/2014 En ligne : https://doi.org/10.1109/TGRS.2014.2346473 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75806
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 3 (March 2015) . - pp 1607 - 1614[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015031 RAB Revue Centre de documentation En réserve L003 Disponible Validation of terrestrial laser scanning data using conventional forest inventory methods / Taye Mengesha in European Journal of Forest Research, vol 134 n° 2 (March 2015)
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Titre : Validation of terrestrial laser scanning data using conventional forest inventory methods Type de document : Article/Communication Auteurs : Taye Mengesha, Auteur ; Michael Hawkins, Auteur ; Maarten Nieuwenhuis, Auteur Année de publication : 2015 Article en page(s) : pp 211 - 222 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] croissance des arbres
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] hauteur des arbres
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Irlande
[Termes IGN] Picea sitchensis
[Termes IGN] placette d'échantillonnage
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) The application of terrestrial laser scanning (TLS) in capturing forest inventory parameters such as diameter at breast height, height and diameters along stem profiles, and in monitoring forest growth, was investigated and validated by comparison with conventionally measured individual tree parameters and plot-level forest growth in a stand of Sitka spruce (Picea sitchensis (Bong.) Carr.) in Ireland. The data acquisition for all the plots with different tree sizes and different slopes was carried out using a terrestrial laser scanner (FARO LS 800 HE80) in November 2007 and November 2009, using the same plot centres and measurement procedures. The point cloud data were processed with Autostem™ software. The results showed that TLS enables the acquisition of forest stand parameters with an acceptable accuracy. Pruning of the lower branches did not improve tree recognition and the number of (partly) occluded trees stayed the same. Over the 2-year period, the average difference between the volume increment of the trees visible to the scanner derived using the conventional method and Autostem™ was 4.77 m3 ha−1 and resulted in scanner-derived estimates that were lower than the estimates obtained by conventional method by 6.1 %. Using a simple correction factor to account for occlusion in the laser scanner data, the difference between these estimates for all trees in the stand became an over-estimation by 6.96 m3 ha−1 (8.1 %). At heights up along the stems >15 m, the errors in stem diameter estimates started to escalate. Numéro de notice : A2015-186 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1007/s10342-014-0844-0l Date de publication en ligne : 21/09/2014 En ligne : https://doi.org/10.1007/s10342-014-0844-0l Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75956
in European Journal of Forest Research > vol 134 n° 2 (March 2015) . - pp 211 - 222[article]Estimating forest biomass from TerraSAR-X stripmap radargrammetry / Svein Solberg in IEEE Transactions on geoscience and remote sensing, vol 53 n° 1 (January 2015)
[article]
Titre : Estimating forest biomass from TerraSAR-X stripmap radargrammetry Type de document : Article/Communication Auteurs : Svein Solberg, Auteur ; Gertrud Riegler, Auteur ; Philippe Nonin, Auteur Année de publication : 2015 Article en page(s) : pp 154 - 161 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] biomasse aérienne
[Termes IGN] image TerraSAR-X
[Termes IGN] inventaire forestier (techniques et méthodes)
[Termes IGN] Norvège
[Termes IGN] Picea (genre)
[Termes IGN] radargrammétrieRésumé : (Auteur) Radargrammetry has a potential for forest inventories, based on the relationship between the canopy height model (CHM) and the forest variables such as biomass. The objective of this study is to describe the relationship between above-ground biomass and a stripmap TerraSAR-X radargrammetry CHM, with emphasis on accuracy and straightness of the relationship. The study was carried out in a spruce forest in south Norway, comprising biomass data from 145 plots of 250 m2 within 21 selected stands. Above-ground biomass for the plots ranged from 0 to 338 t/ha. We derived a digital surface model (DSM) from six TerraSAR-X stripmap acquisitions by automatic stereo matching. We subtracted a digital terrain model (DTM) from the DSM and obtained a CHM. We assigned the nearest 10 m × 10 m pixel to each field plot. The height of the CHM increased linearly with biomass with 15 t/ha/m. The rmse values were 23 t/ha (18%) at the stand level and 58 t/ha (44%) at the plot level. The tendency of curvilinearity was so weak that it could hardly be distinguished from a straight linear relationship. The straightness of the relationship may enable monitoring of biomass changes without an external DTM as input. A comparison between radargrammetry and interferometric synthetic aperture radar (InSAR) showed that the relationship between the biomass and their respective CHMs was almost identical in terms of parameter estimates. The strength of the relationship was higher with InSAR. By combining ascending and descending pairs followed by editing, the performance of radargrammetry was equally good as with InSAR. Numéro de notice : A2015-028 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2014.2319853 En ligne : https://doi.org/10.1109/TGRS.2014.2319853 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75109
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 1 (January 2015) . - pp 154 - 161[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015011 RAB Revue Centre de documentation En réserve L003 Disponible The Forests in Germany / Federal ministry of food and agriculture = Bundesministerium für Ernährung und Landwirtschaft (Berlin, Allemagne) (2015)
Titre : The Forests in Germany : selected results of the third national forest inventory Type de document : Rapport Auteurs : Federal ministry of food and agriculture = Bundesministerium für Ernährung und Landwirtschaft (Berlin, Allemagne), Auteur ; Christian Schmidt, Préfacier, etc. Editeur : Berlin : Federal ministry of food and agriculture BMEL Année de publication : 2015 Importance : 54 p. Format : 21 x 30 cm Note générale : Glossaire Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] biotope
[Termes IGN] changement climatique
[Termes IGN] espèce exotique envahissante
[Termes IGN] Fagus (genre)
[Termes IGN] forêt
[Termes IGN] habitat forestier
[Termes IGN] Picea abies
[Termes IGN] Pinus (genre)
[Termes IGN] Quercus (genre)
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] surveillance forestière
[Vedettes matières IGN] Ecologie forestièreRésumé : (Editeur) [Introduction] The forest possesses many talents. It is a home for animals and plants, an important climate protector and contains a wealth of biological diversity. For us, it is also an important supplier of raw materials. We need timber to build houses and furniture, for the production of energy and for the paper on which this booklet is printed. The forest is, however, also a place of peace and quiet that offers us refuge and recreation in our hectic, fast-paced world. Therefore, the forest is indispensable for all of our lives. One third of Germany is forested over 11.4 million hectares. The Third National Forest Inventory (NFI) provides good news: Our forest area has remained unchanged. More timber is re-growing than we use. We also have more of it than any other country in the European Union. In spite of high use, our forest stocks rose to 3.7 billion cubic metres. The appearance of German forests is characterized by 90 billion old and young spruces, pines, beeches, oaks and other tree species. The percentage of deciduous trees has risen. The forests have become more diverse and natural in structure. We find more deadwood in them – an important foundation for biodiversity. The good condition of our forests is the consequence of the silvicultural actions of many forest owners and foresters and the result of a forestry policy based on balance and sustainability that distributes the responsibilities on many shoulders: roughly half of German forests are privately owned. One fifth of them are owned by municipalities, cities and other public entities. One third belong to the Länder and the Federal government. But the National Forest Inventory also indicates the need for action. One example is the spruce: the NFI confirms that the spruce – an important supplier of raw material for the timber industry – is in decline. We must therefore talk about how much spruce forest we need and what alternatives there are to the spruce in the face of climate change. The forest should be used in the best possible way without overtaxing it. To make sure of this, the Federal government devised the Forest Strategy 2020. Its objective is to express and harmonize our diverse demands on the forest. This is the only way to maintain our chances for having intact forests for future generations as well. That is why my maxim is “Our forests: utilize and preserve.” The aim of this booklet is to generate understanding for the forest, forest owners and foresters. It provides citizens with the opportunity to get to know the functions of the forest and appreciate its value. Hence, the booklet is a contribution to sustainable forest management. Note de contenu : 1. Germany, the land of forests – forest area unchanged
- The forests – mainly privately owned
- Varying forest abundance in the Länder
2. The forest habitat – more biological diversity in the forest
- Spruce, pine, beech, oak – the most common tree species
- Forest damage led to rethinking – climate change faces us with new challenges
- Increase in older forests
- Rise in numbers of deciduous trees
- Forests more diversely structured
- Naturalness of tree species composition is somewhat improved
- More deadwood found than ten years ago
- Specially protected biotopes on five percent of the forest area
- Invasive plants in the forest are currently of little significance
- Biotope trees – stepping stones for biological diversity
- Conservation status of large-area forest habitat types protected under the Fauna-Flora-Habitats Directive
3. The forest resources – timber stock at record high
- Stock rose again
- Rise in stock primarily among large-girth trees
- The special case of spruce – stock decreased
- Timber increment at a high level
- Timber use at a high level
- Growth greater than use
- Timber use increasingly restricted or suspended
4. The forests as climate protectors – still a carbon sink
5. Surveying the forest
- Open during inventory – the inventory procedure
- National Forest Inventory – established information basisNuméro de notice : 22453 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Rapport Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79981 Documents numériques
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22453-Forests_in_Germany-BWI.pdfAdobe Acrobat PDF PermalinkEconomics of harvesting uneven-aged forest stands in Fennoscandia / Janne Rämo in Scandinavian journal of forest research, vol 29 n° 8 (October 2014)PermalinkSpatial patterns of historical growth changes in Norway spruce across western European mountains and the key effect of climate warming / Marie Charru in Trees, vol 28 n° 1 (February 2014)PermalinkLa forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2014)PermalinkSingle tree biomass modelling using airborne laser scanning / Ville Kankare in ISPRS Journal of photogrammetry and remote sensing, vol 85 (November 2013)PermalinkLe statut social d’un arbre influence-t-il sa réponse au climat ? Étude dendroécologique sur le Sapin, l’Epicéa, le Pin sylvestre, le Hêtre et le Chêne sessile / Pierre Mérian in Revue forestière française, vol 65 n°1 (janvier - février 2013)PermalinkLa forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2013)PermalinkOak (Quercus robur L.) regeneration as a response to natural dynamics of stands in European hemiboreal zone / Andrzej Bobiec in European Journal of Forest Research, vol 130 n° 5 (September 2011)PermalinkInterCETEF 2009 en Auvergne : diagnostiquer les risques, pour mieux les prévenir / Alain Colinot in Forêt entreprise, n° 191 (mars 2010/2)PermalinkLutte engagée contre le dendroctone de l'épicéa / Abdel Moutaoukil in Le Bois International : l'officiel du bois [édition verte], vol 2010 n° 3 (23 janvier 2010)Permalink