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Accelerated deforestation driven by large-scale land acquisitions in Cambodia / Kyle Frankel Davis in Nature geoscience, vol 8 n° 10 (October 2015)
[article]
Titre : Accelerated deforestation driven by large-scale land acquisitions in Cambodia Type de document : Article/Communication Auteurs : Kyle Frankel Davis, Auteur ; Kailiang Yu, Auteur ; Maria Cristina Rulli, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 772 - 775 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Cambodge
[Termes IGN] couvert forestier
[Termes IGN] couvert végétal
[Termes IGN] déboisementRésumé : (auteur) Investment in agricultural land in the developing world has rapidly increased in the past two decades. In Cambodia, there has been a surge in economic land concessions, in which long-term leases are provided to foreign and domestic investors for economic development. More than two million hectares have been leased so far, sparking debate over the consequences for local communities and the environment. Here we combined official records of concession locations with a high-resolution data set of changes in forest cover to quantify the contribution of land concessions to deforestation between 2000 and 2012. We used covariate matching to control for variables other than classification as a concession that may influence forest loss. Nearly half of the area where concessions were granted between 2000 and 2012 was forested in 2000; this area then represented 12.4% of forest land cover in Cambodia. Within concessions, the annual rate of forest loss was between 29% and 105% higher than in comparable land areas outside concessions. Most of the deforestation within concessions occurred after the contract date, and whether an investor was domestic or foreign had no effect on deforestation rates. We conclude that land acquisitions can act as powerful drivers of deforestation. Numéro de notice : A2015-500 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1038/ngeo2540 En ligne : https://doi.org/10.1038/ngeo2540 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77330
in Nature geoscience > vol 8 n° 10 (October 2015) . - pp 772 - 775[article]Caring for the planet’s lungs / Judith Metschies in GEO: Geoconnexion international, vol 14 n° 9 (October 2015)
[article]
Titre : Caring for the planet’s lungs Type de document : Article/Communication Auteurs : Judith Metschies, Auteur Année de publication : 2015 Article en page(s) : pp 36 - 39 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] gestion durable
[Termes IGN] image satellite
[Termes IGN] image SPOT 6
[Termes IGN] surveillance de la végétation
[Termes IGN] sylvicultureRésumé : (éditeur) A sixth of the earth’s forest cover is in africa and safeguarding it is a vital task. Judith Metschies looks at how satellite imagery is being used to ensure forestry is managed sustainably on the continent Numéro de notice : A2015-653 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : sans Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78257
in GEO: Geoconnexion international > vol 14 n° 9 (October 2015) . - pp 36 - 39[article]Investigating the robustness of the new Landsat-8 Operational Land Imager derived texture metrics in estimating plantation forest aboveground biomass in resource constrained areas / Timothy Dube in ISPRS Journal of photogrammetry and remote sensing, vol 108 (October 2015)
[article]
Titre : Investigating the robustness of the new Landsat-8 Operational Land Imager derived texture metrics in estimating plantation forest aboveground biomass in resource constrained areas Type de document : Article/Communication Auteurs : Timothy Dube, Auteur ; Onisimo Mutanga, Auteur Année de publication : 2015 Article en page(s) : pp 12 – 32 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Acquisition d'image(s) et de donnée(s)
[Termes IGN] Afrique du sud (état)
[Termes IGN] biodiversité
[Termes IGN] biomasse aérienne
[Termes IGN] biomasse forestière
[Termes IGN] classification
[Termes IGN] classification dirigée
[Termes IGN] espèce végétale
[Termes IGN] Eucalyptus dunii
[Termes IGN] Eucalyptus grandis
[Termes IGN] image Landsat-8
[Termes IGN] image Landsat-OLI
[Termes IGN] Pinus taeda
[Termes IGN] régression
[Termes IGN] sous-étage
[Termes IGN] sylviculture
[Termes IGN] texture d'imageRésumé : (auteur) The successful launch of the 30-m Landsat-8 Operational Land Imager (OLI) pushbroom sensor offers a new primary data source necessary for aboveground biomass (AGB) estimation, especially in resource-limited environments. In this work, the strength and performance of Landsat-8 OLI image derived texture metrics (i.e. texture measures and texture ratios) in estimating plantation forest species AGB was investigated. It was hypothesized that the sensor’s pushbroom design, coupled with the presence of refined spectral properties, enhanced radiometric resolution (i.e. from 8 bits to 12 bits) and improved signal-to-noise ratio have the potential to provide detailed spectral information necessary for significantly strengthening AGB estimation in medium-density forest canopies. The relationship between image texture metrics and measurements of forest attributes can be used to help characterize complex forests, and enhance fine vegetation biophysical properties, a difficult challenge when using spectral vegetation indices especially in closed canopies. This study examines the prospects of using Landsat-8 OLI sensor derived texture metrics for estimating AGB for three medium-density plantation forest species in KwaZulu Natal, South Africa. In order to achieve this objective, three unique data pre-processing techniques were tested (analysis I: Landsat-8 OLI raw spectral-bands vs. raw texture bands; analysis II: Landsat-8 OLI raw spectral-band ratios vs. texture band ratios and analysis III: Landsat-8 OLI derived vegetation indices vs. texture band ratios). The landsat-8 OLI derived texture parameters were examined for robustness in estimating AGB using linear regression, stepwise-multiple linear regression and stochastic gradient boosting regression models. The results of this study demonstrated that all texture parameters particularly band texture ratios calculated using a 3 × 3 window size, could enhance AGB estimation when compared to simple spectral reflectance, simple band ratios and the most popular spectral vegetation indices. For instance, the use of combined texture ratios yielded the highest R2 values of 0.76 (RMSE = 9.55 t ha−1 (18.07%) and CV-RMSE of 0.18); 0.74 (RMSE = 12.81 t ha−1 (17.72%) and CV-RMSE of 0.08); 0.74 (RMSE = 12.67 t ha−1 (06.15%) and CV-RMSE of 0.06) and 0.53 (RMSE = 20.15 t ha−1 (14.40%) and CV-RMSE of 0.15) overall for Eucalyptus dunii, Eucalyptus grandis, Pinus taeda individually and all species, respectively. Overall, the findings of this study provide the necessary insight and motivation to the remote sensing community, particularly in resource constrained regions, to shift towards embracing various texture metrics obtained from the readily-available and cheap multispectral Landsat-8 OLI sensor. Numéro de notice : A2015-849 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2015.06.002 Date de publication en ligne : 25/06/2015 En ligne : http://dx.doi.org/10.1016/j.isprsjprs.2015.06.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79219
in ISPRS Journal of photogrammetry and remote sensing > vol 108 (October 2015) . - pp 12 – 32[article]Land cover changes assessment using object-based image analysis in the Binah River watershed (Togo and Benin) / Hèou Maléki Badjana in Earth and space science, vol 2 n° 10 (October 2015)
[article]
Titre : Land cover changes assessment using object-based image analysis in the Binah River watershed (Togo and Benin) Type de document : Article/Communication Auteurs : Hèou Maléki Badjana, Auteur ; Jörg Helmschrot, Auteur ; Peter Selsam, Auteur ; Kperkouma Wala, Auteur ; et al., Auteur Année de publication : 2015 Article en page(s) : pp 403 - 416 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse d'image orientée objet
[Termes IGN] analyse diachronique
[Termes IGN] bassin hydrographique
[Termes IGN] Bénin
[Termes IGN] changement d'occupation du sol
[Termes IGN] déboisement
[Termes IGN] détection de changement
[Termes IGN] image Landsat-MSS
[Termes IGN] image Landsat-OLI
[Termes IGN] image Landsat-TM
[Termes IGN] occupation du sol
[Termes IGN] savane
[Termes IGN] TogoRésumé : (auteur) In this study, land cover changes between 1972 and 2013 were investigated in the Binah River watershed (North of Togo and Benin) using remote sensing and geographic information system technologies. Multitemporal satellite images—Landsat MSS (1972), TM (1987), and OLI-TIRS (2013)—were processed using object-based image analysis and post–classification comparison methods including landscape metrics and changes trajectories analysis. Land cover maps referring to five main land cover classes, namely, agricultural land, forest land, savannah, settlements, and water bodies, were produced for each acquisition date. The overall accuracies were 76.64% (1972), 83.52% (1987), and 88.84% (2013) with respective Kappa statistics of 0.69, 0.78, and 0.86. The assessment of the spatiotemporal pattern of land cover changes indicates that savannah, the main vegetation type, has undergone the most dominant change, decreasing from 67% of the basin area in 1972 to 56% in 1987 and 33% in 2013. At the same time, agricultural land has significantly increased from 15% in 1972 to 24% in 1987 and 43% in 2013, while some proportions of agricultural land were converted to savannah relating to fallow agriculture. In total, more than 55% of the landscape experienced changes between 1972 and 2013. These changes are primarily due to human activities and population growth. In addition, agricultural activities significantly contributed to the increase in the number of patches, degree of division, and splitting index of forest and savannah vegetations and the decrease in their effective mesh sizes. These results indicate further fragmentation of forest and savannah vegetations between 1972 and 2013. Further research is needed to quantitatively evaluate the influences of individual factors of human activities and to separate these from the impacts of climate change-driven disturbances. Numéro de notice : A2015--042 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : doi.org/10.1002/2014EA000083 En ligne : http://dx.doi.org/10.1002/2014EA000083 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81804
in Earth and space science > vol 2 n° 10 (October 2015) . - pp 403 - 416[article]Managing tree plantations as novel socioecological systems: Australian and North American perspectives / David Lindenmayer in Canadian Journal of Forest Research, vol 45 n° 10 (October 2015)
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Titre : Managing tree plantations as novel socioecological systems: Australian and North American perspectives Type de document : Article/Communication Auteurs : David Lindenmayer, Auteur ; Christian Messier, Auteur ; Alain Paquette, Auteur ; Richard J. Hobbs, Auteur Année de publication : 2015 Article en page(s) : pp 1427 - 1433 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] anthropisation
[Termes IGN] boisement artificiel
[Termes IGN] conservation des ressources forestières
[Termes IGN] écosystème forestier
[Termes IGN] impact sur l'environnement
[Termes IGN] protection de la biodiversité
[Termes IGN] protection du paysage
[Termes IGN] sylviculture
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Des écosystèmes nouveaux apparaissent lorsque de nouvelles combinaisons d’espèces se forment dans un biome particulier. Ils résultent en général directement de l’activité humaine, de changements environnementaux ou des impacts d’espèces introduites. Dans cet article, nous soutenons que le fait de considérer les plantations forestières commerciales comme des écosystèmes nouveaux a le potentiel d’aider les décideurs politiques, les gestionnaires des ressources et les biologistes de la conservation à mieux faire face aux défis et opportunités associés à la gestion des plantations à des fins multiples tant à l’échelle du peuplement que du paysage. Nous présentons cinq enjeux interdépendants associés à la gestion des plantations forestières qui constituent sans doute la plus vaste forme d’écosystème terrestre nouveau dans le monde. Le but est de s’assurer que ces zones contribuent de façon significative aux services essentiels de l’écosystème, incluant la conservation de la biodiversité en plus de leur rôle dans la production de matière ligneuse. Nous croyons que le fait de considérer les plantations forestières comme des écosystèmes socio-écologiques nouveaux peut libérer les gestionnaires d’une perspective étroite fondée sur le peuplement et les exempter d’avoir à prendre comme point de comparaison des peuplements de forêt naturelle. Cela peut contribuer à promouvoir le développement de principes d’aménagement qui intègrent mieux les plantations dans le paysage plus large de telle sorte que leurs bénéfices soient maximisés et que leurs impacts écologiques potentiellement néfastes soient minimisés. Numéro de notice : A2015-672 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1139/cjfr-2015-007 En ligne : http://www.nrcresearchpress.com/doi/abs/10.1139/cjfr-2015-0072 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78290
in Canadian Journal of Forest Research > vol 45 n° 10 (October 2015) . - pp 1427 - 1433[article]Modeling the above and belowground biomass of planted and coppiced Eucalytpus globulus stands in NW Spain / Daniel J. Vega-Nieva in Annals of Forest Science, vol 72 n° 7 (October 2015)PermalinkMonitoring ectomycorrhizal fungi at large scales for science, forest management, fungal conservation and environmental policy / Laura M. Suz in Annals of Forest Science, vol 72 n° 7 (October 2015)PermalinkTropical forest canopy cover estimation using satellite imagery and airborne lidar reference data / Lauri Korhonen in Silva fennica, vol 49 n° 5 ([01/10/2015])PermalinkEstimation of forest biomass from two-level model inversion of single-pass InSAR data / M.J. Soja in IEEE Transactions on geoscience and remote sensing, vol 53 n° 9 (September 2015)PermalinkHow much do we know about the endangered Atlantic Forest? Reviewing nearly 70 years of information on tree community surveys / Renato A.F. de Lima in Biodiversity & Conservation, vol 24 n° 9 (September 2015)PermalinkMonitoring forest cover loss using multiple data streams, a case study of a tropical dry forest in Bolivia / Loïc Paul Dutrieux in ISPRS Journal of photogrammetry and remote sensing, vol 107 (September 2015)PermalinkMonitoring of chronological stages of deforestation-afforestation: the case of Southern Chile / Nicolas Maestripieri in Photo interprétation, European journal of applied remote sensing, vol 51 n° 3 (septembre 2015)PermalinkQuantitative evaluation of volunteered geographic information paradigms: social location-based services case study / B. Lipej in Survey review, vol 47 n° 344 (September 2015)PermalinkRecommendations for the use of tree models to estimate national forest biomass and assess their uncertainty / Matieu Henry in Annals of Forest Science, vol 72 n° 6 (September 2015)PermalinkModelling the constraints of spatial environment in fauna movement simulations: comparison of a boundaries accurate function and a cost function / Laurence Jolivet in ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences, vol II-3 W5 (October 2015)Permalink