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Dead wood availability in managed Swedish forests – Policy outcomes and implications for biodiversity / Bengt Gunnar Jonsson in Forest ecology and management, vol 376 (15 September 2016)
[article]
Titre : Dead wood availability in managed Swedish forests – Policy outcomes and implications for biodiversity Type de document : Article/Communication Auteurs : Bengt Gunnar Jonsson, Auteur ; Magnus Ekström, Auteur ; Per-Anders Esseen, Auteur ; Anton Grafström, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 174 - 182 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] biodiversité végétale
[Termes IGN] bois mort
[Termes IGN] gestion forestière durable
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Picea abies
[Termes IGN] politique de conservation (biodiversité)
[Termes IGN] Suède
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Dead wood is a critical resource for forest biodiversity and widely used as an indicator for sustainable forest management. Based on data from the Swedish National Forest Inventory we provide baseline information and analyze trends in volume and distribution of dead wood in Swedish managed forests during 15 years. The data are based on ≈30,000 sample plots inventoried during three periods (1994–1998; 2003–2007 and 2008–2012). The forest policy has since 1994 emphasized the need to increase the amount of dead wood in Swedish forests. The average volume of dead wood in Sweden has increased by 25% (from 6.1 to 7.6 m3 ha−1) since the mid-1990s, but patterns differed among regions and tree species. The volume of conifer dead wood (mainly from Picea abies) has increased in the southern part of the country, but remained stable or decreased in the northern part. Heterogeneity of dead wood types was low in terms of species, diameter and decay classes, potentially negatively impacting on biodiversity. Overall, we found only minor effects of the current forest policy since most of the increase can be attributed to storm events creating a pulse of hard dead wood. Therefore, the implementation of established policy instruments (e.g. legislation and voluntary certification schemes) need to be revisited. In addition to the retention of dead trees during forestry operations, policy makers should consider calling for more large-scale targeted creation of dead trees and management methods with longer rotation cycles. Numéro de notice : A2016-708 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.foreco.2016.06.017 En ligne : http://dx.doi.org/10.1016/j.foreco.2016.06.017 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=82081
in Forest ecology and management > vol 376 (15 September 2016) . - pp 174 - 182[article]Extreme events and climate change: the post-disaster dynamics of forest fires and forest storms in Sweden / Rolf Lidskog in Scandinavian journal of forest research, vol 31 n° 2 (March 2016)
[article]
Titre : Extreme events and climate change: the post-disaster dynamics of forest fires and forest storms in Sweden Type de document : Article/Communication Auteurs : Rolf Lidskog, Auteur ; Daniel Sjödin, Auteur Année de publication : 2016 Article en page(s) : pp 148 - 155 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] catastrophe naturelle
[Termes IGN] changement climatique
[Termes IGN] dommage matériel
[Termes IGN] forêt
[Termes IGN] incendie de forêt
[Termes IGN] Pinophyta
[Termes IGN] Suède
[Termes IGN] tempête
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) How are extreme events understood in the forest sector? What are the implications of forest professionals' understandings and evaluations of extreme events? These questions are central to this study, which analyses the handling of the largest forest storm and the largest forest fire in modern Swedish history. The theoretical approach is that of risk governance in practice, which stresses that understanding the framings, practices and strategies used by members of professional organizations is pivotal for how disasters are managed. Two interview studies have been conducted with forest professionals involved in the two cases. The analysis shows that there were fundamentally different understandings of the two events and their implications for forestry practice. The storm was seen as an unavoidable natural disaster, but the consequences of future storms were considered possible to mitigate through changed forest practices. The forest fire, on the other hand, was conceptualized as a partly natural and partly man-made disaster, and forestry was seen as having very limited possibilities to reduce the likelihood as well as the consequences of similar events. The different understandings had significant implications for the post-disaster dynamics and for which management practices that were developed. Thus, understanding how extreme events are perceived is crucial to understanding which management practices that emerge in their wake, a topic of growing relevance because climate change is predicted to increase the frequency of forest fires and storms. Numéro de notice : A2016-017 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1080/02827581.2015.1113308 Date de publication en ligne : 20/11/2015 En ligne : http://dx.doi.org/10.1080/02827581.2015.1113308 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79382
in Scandinavian journal of forest research > vol 31 n° 2 (March 2016) . - pp 148 - 155[article]Estimation 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)
[article]
Titre : Estimation of forest biomass from two-level model inversion of single-pass InSAR data Type de document : Article/Communication Auteurs : M.J. Soja, Auteur ; Henrik J. Persson, Auteur ; Lars M.H. Ulander, Auteur Année de publication : 2015 Article en page(s) : pp 5083 - 5099 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image radar et applications
[Termes IGN] biomasse forestière
[Termes IGN] forêt boréale
[Termes IGN] image TanDEM-X
[Termes IGN] interféromètrie par radar à antenne synthétique
[Termes IGN] modèle numérique de terrain
[Termes IGN] placette d'échantillonnage
[Termes IGN] polarimétrie radar
[Termes IGN] SuèdeRésumé : (Auteur) A model for aboveground biomass estimation from single-pass interferometric synthetic aperture radar (InSAR) data is presented. Forest height and canopy density estimates Δh and η0, respectively, obtained from two-level model (TLM) inversion, are used as biomass predictors. Eighteen bistatic VV-polarized TanDEM-X (TDM) acquisitions are used, made over two Swedish test sites in the summers of 2011, 2012, and 2013 (nominal incidence angle: 41°; height-of-ambiguity: 32-63 m). Remningstorp features a hemiboreal forest in southern Sweden, with flat topography and where 32 circular plots have been sampled between 2010 and 2011 (area: 0.5 ha; biomass: 42-242 t/ha; height: 14-32 m) . Krycklan features a boreal forest in northern Sweden, 720-km north-northeast from Remningstorp, with significant topography and where 31 stands have been sampled in 2008 (area: 2.4-26.3 ha; biomass: 23-183 t/ha; height: 7-21 m). A high-resolution digital terrain model has been used as ground reference during InSAR processing. For the aforementioned plots and stands and if the same acquisition is used for model training and validation, the new model explains 65%-89% of the observed variance, with root-mean-square error (RMSE) of 12%-19% (median: 15%) . By fixing two of the three model parameters, accurate biomass estimation can also be done when different acquisitions or different test sites are used for model training and validation, with RMSE of 12%-56% (median: 17%). Compared with a simple scaling model computing biomass from the phase center elevation above ground, the proposed model shows significantly better performance in Remningstorp, as it accounts for the large canopy density variations caused by active management. In Krycklan, the two models show similar performance. Numéro de notice : A2015-525 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2015.2417205 Date de publication en ligne : 24/04/2015 En ligne : https://doi.org/10.1109/TGRS.2015.2417205 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=77536
in IEEE Transactions on geoscience and remote sensing > vol 53 n° 9 (September 2015) . - pp 5083 - 5099[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 065-2015091 SL Revue Centre de documentation Revues en salle Disponible Matching authority and VGI road networks using an extended node-based matching algorithm / Ehsan Abdolmajidi in Geo-spatial Information Science, vol 18 n° 2 (August 2015)
[article]
Titre : Matching authority and VGI road networks using an extended node-based matching algorithm Type de document : Article/Communication Auteurs : Ehsan Abdolmajidi, Auteur ; Ali Mansourian, Auteur ; Julian Will, Auteur ; Lars Harrie, Auteur Année de publication : 2015 Article en page(s) : pp 65 - 80 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Infrastructure de données
[Termes IGN] appariement topologique
[Termes IGN] base de données routières
[Termes IGN] données localisées de référence
[Termes IGN] données localisées des bénévoles
[Termes IGN] OpenStreetMap
[Termes IGN] qualité des données
[Termes IGN] relation topologique
[Termes IGN] réseau routier
[Termes IGN] SuèdeRésumé : (auteur) The amount of volunteered geographic information (VGI) has increased over the past decade, and several studies have been conducted to evaluate the quality of VGI data. In this study, we evaluate the completeness of the road network in the VGI data set OpenStreetMap (OSM). The evaluation is based on an accurate and efficient network-matching algorithm. The study begins with a comparison of the two main strategies for network matching: segment-based and node-based matching. The comparison shows that the result quality is comparable for the two strategies, but the node-based result is considerably more computationally efficient. Therefore, we improve the accuracy of node-based algorithm by handling topological relationships and detecting patterns of complicated network components. Finally, we conduct a case study on the extended node-based algorithm in which we match OSM to the Swedish National Road Database (NVDB) in Scania, Sweden. The case study reveals that OSM has a completeness of 87% in the urban areas and 69% in the rural areas of Scania. The accuracy of the matching process is approximately 95%. The conclusion is that the extended node-based algorithm is sufficiently accurate and efficient for conducting surveys of the quality of OSM and other VGI road data sets in large geographic regions. Numéro de notice : A2015-760 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE/INFORMATIQUE Nature : Article DOI : 10.1080/10095020.2015.1071065 En ligne : http://dx.doi.org/10.1080/10095020.2015.1071065 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78796
in Geo-spatial Information Science > vol 18 n° 2 (August 2015) . - pp 65 - 80[article]Determination of the local tie vector between the VLBI and GNSS reference points at Onsala using GPS measurements / Tong Ning in Journal of geodesy, vol 89 n° 7 (July 2015)
[article]
Titre : Determination of the local tie vector between the VLBI and GNSS reference points at Onsala using GPS measurements Type de document : Article/Communication Auteurs : Tong Ning, Auteur ; Rüdiger Haas, Auteur ; Gunnar Elgered, Auteur Année de publication : 2015 Article en page(s) : pp 711 - 723 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie spatiale
[Termes IGN] analyse comparative
[Termes IGN] co-positionnement
[Termes IGN] données GPS
[Termes IGN] données ITGB
[Termes IGN] écart type
[Termes IGN] point de liaison (géodésie)
[Termes IGN] point géodésique
[Termes IGN] précision millimétrique
[Termes IGN] SuèdeRésumé : (auteur) Two gimbal-mounted GNSS antennas were installed on each side of the radome-enclosed 20 m VLBI radio telescope at the Onsala Space Observatory. GPS data with a 1 Hz sampling rate were recorded for five semi-kinematic and four kinematic observing campaigns. These GPS data were analysed together with data from the IGS station ONSA with an in-house Matlab-based GPS software package, using the double-difference analysis strategy. The coordinates of the GNSS antennas on the telescope were estimated for different observation angles of the telescope, at specific epochs, and used to calculate the geodetic reference point of the telescope. The local tie vector between the VLBI and the ONSA GNSS reference points in a geocentric reference frame was hence obtained. The two different types of observing campaigns gave consistent results of the estimated local tie vector and the axis offset of the telescope. The estimated local tie vector obtained from all nine campaigns gave standard deviations of 1.5, 1.0, and 2.9 mm for the geocentric X, Y, and Z components, respectively. The result of the estimated axis offset of the VLBI telescope shows a difference of 0.3 mm, with a standard deviation of 1.9 mm, with respect to a reference value obtained by two local surveys carried out in 2002 and 2008. Our results show that the presented method can be used as a complement to the more accurate but more labour intensive classical geodetic surveys to continuously monitor the local tie at co-location stations with an accuracy of a few millimetres Numéro de notice : A2015-355 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00190-015-0809-1 Date de publication en ligne : 05/04/2015 En ligne : https://doi.org/10.1007/s00190-015-0809-1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76778
in Journal of geodesy > vol 89 n° 7 (July 2015) . - pp 711 - 723[article]A Swedish case study on the prediction of detailed product recovery from individual stem profiles based on airborne laser scanning / Andreas Barth in Annals of Forest Science, vol 72 n° 1 (January 2015)PermalinkMeasurements of forest biomass change using P-Band synthetic aperture radar backscatter / Gustaf Sandberg in IEEE Transactions on geoscience and remote sensing, vol 52 n° 10 tome 1 (October 2014)PermalinkSpatial modeling of the black death in Sweden / Lars Skog in Transactions in GIS, vol 17 n° 4 (August 2013)Permalink3D online: Crowdsourcing for city planning / E. Jeansson in GIM international, vol 26 n° 12 (December 2012)PermalinkModelling flow routing in permafrost landscapes with TWI: an evaluation against site-specific wetness measurements / A. Persson in Transactions in GIS, vol 16 n° 5 (October 2012)PermalinkAutomatic symbolisation methods for geoportals / Ara Toomanian in Cartographic journal (the), vol 49 n° 2 (May 2012)PermalinkIndividual tree biomass equations or biomass expansion factors for assessment of carbon stock changes in living biomass: A comparative study / Hans Petersson in Forest ecology and management, vol 270 (April 2012)PermalinkSwedish Lidar Project: New Nationwide Elevation Model / Y. Petersen in GIM international, vol 25 n° 2 (February 2011)PermalinkUsing landscape characteristics to define an adjusted distance metric for improving kriging interpolations / S. Lyon in International journal of geographical information science IJGIS, vol 24 n° 5-6 (may 2010)PermalinkInventorying management status and plant species richness in seminatural grasslands using high spatial resolution imagery / K. Hall in Applied Vegetation Science, vol 13 n° 2 (April 2010)Permalink