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A representativeness-directed approach to mitigate spatial bias in VGI for the predictive mapping of geographic phenomena / Guiming Zhang in International journal of geographical information science IJGIS, vol 33 n° 9 (September 2019)
[article]
Titre : A representativeness-directed approach to mitigate spatial bias in VGI for the predictive mapping of geographic phenomena Type de document : Article/Communication Auteurs : Guiming Zhang, Auteur ; A - Xing Zhu, Auteur Année de publication : 2019 Article en page(s) : pp 1873 - 1893 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] Aves
[Termes IGN] carte thématique
[Termes IGN] distribution spatiale
[Termes IGN] données localisées des bénévoles
[Termes IGN] échantillon
[Termes IGN] erreur d'échantillon
[Termes IGN] erreur de positionnement
[Termes IGN] erreur systématique
[Termes IGN] habitat (nature)
[Termes IGN] modèle de simulation
[Termes IGN] phénomène géographique
[Termes IGN] pondération
[Termes IGN] précision de localisation
[Termes IGN] régression logistique
[Termes IGN] representativité
[Termes IGN] science citoyenne
[Termes IGN] Wisconsin (Etats-Unis)Résumé : (auteur) Volunteered geographic information (VGI) contains valuable field observations that represent the spatial distribution of geographic phenomena. As such, it has the potential to provide regularly updated low-cost field samples for predictively mapping the spatial variations of geographic phenomena. The predictive mapping of geographic phenomena often requires representative samples for high mapping accuracy, but samples consisting of VGI observations are often not representative as they concentrate on specific geographic areas (i.e. spatial bias) due to the opportunistic nature of voluntary observation efforts. In this article, we propose a representativeness-directed approach to mitigate spatial bias in VGI for predictive mapping. The proposed approach defines and quantifies sample representativeness by comparing the probability distributions of sample locations and the mapping area in the environmental covariate space. Spatial bias is mitigated by weighting the sample locations to maximize their representativeness. The approach is evaluated using species habit suitability mapping as a case study. The results show that the accuracy of predictive mapping using weighted sample locations is higher than using unweighted sample locations. A positive relationship between sample representativeness and mapping accuracy is also observed, suggesting that sample representativeness is a valid indicator of predictive mapping accuracy. This approach mitigates spatial bias in VGI to improve predictive mapping accuracy. Numéro de notice : A2019-392 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1615071 Date de publication en ligne : 10/05/2019 En ligne : https://doi.org/10.1080/13658816.2019.1615071 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93490
in International journal of geographical information science IJGIS > vol 33 n° 9 (September 2019) . - pp 1873 - 1893[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 079-2019091 RAB Revue Centre de documentation En réserve L003 Disponible 079-2019092 RAB Revue Centre de documentation En réserve L003 Disponible Diptera in clear-felling stumps like it dry / Mats Jonsell in Scandinavian journal of forest research, vol 34 n° 8 (August 2019)
[article]
Titre : Diptera in clear-felling stumps like it dry Type de document : Article/Communication Auteurs : Mats Jonsell, Auteur ; Clémentine Ols , Auteur ; Jonas Victorsson, Auteur ; Sven Hellqvist, Auteur Année de publication : 2019 Projets : 1-Pas de projet / Article en page(s) : pp 673 - 677 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Betula (genre)
[Termes IGN] bioénergie
[Termes IGN] bois mort
[Termes IGN] Coleoptera (ordre)
[Termes IGN] coupe rase (sylviculture)
[Termes IGN] diptère
[Termes IGN] échantillonnage
[Termes IGN] indice d'humidité
[Termes IGN] Insecta
[Termes IGN] Picea abies
[Termes IGN] souche
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) When stumps on clear cuts are harvested for bioenergy, retention of a share of them is recommended to mitigate environmental issues. To maximise benefits for the diversity of saproxylic beetles, retention should be done in dry positions. Saproxylic dipterans are usually thought to be associated with wetter wood substrates. We therefore hypothesised that dipterans would benefit from other recommendations. We tested that by rearing out insects from spruce and birch stumps sampled in clear fellings, and received a material of 866 individuals of 24 Diptera taxa. Among six Diptera species tested statistically, one was associated with dry stumps when comparing within spruce, and the total abundance of dipterans was higher in dry spruce stumps than in wet. No parameter (total species number, species number per stump, total abundances and abundances of individual species) showed a higher value for wet stumps than for dry. We conclude that there are several Diptera species that frequently use stumps, of which a large share was earlier regarded as very rare. For those, our hypothesis was falsified, as the affinities to dry stumps seem similar as for beetles and the same recommendations could be used. Numéro de notice : A2019-617 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : BIODIVERSITE/FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/02827581.2019.1663916 Date de publication en ligne : 16/09/2019 En ligne : https://doi.org/10.1080/02827581.2019.1663916 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95344
in Scandinavian journal of forest research > vol 34 n° 8 (August 2019) . - pp 673 - 677[article]Interpreting effects of multiple, large-scale disturbances using national forest inventory data: A case study of standing dead trees in east Texas, USA / Christopher B. Edgar in Forest ecology and management, vol 437 (1 April 2019)
[article]
Titre : Interpreting effects of multiple, large-scale disturbances using national forest inventory data: A case study of standing dead trees in east Texas, USA Type de document : Article/Communication Auteurs : Christopher B. Edgar, Auteur ; James A. Westfall, Auteur ; Paul A. Klockow, Auteur ; et al., Auteur Année de publication : 2019 Article en page(s) : pp 27-40 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] agrégation temporelle
[Termes IGN] analyse diachronique
[Termes IGN] arbre mort
[Termes IGN] catastrophe naturelle
[Termes IGN] diamètre à hauteur de poitrine
[Termes IGN] données dendrométriques
[Termes IGN] échantillonnage
[Termes IGN] gestion forestière
[Termes IGN] insecte nuisible
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] jeu de données
[Termes IGN] maladie phytosanitaire
[Termes IGN] Pinus (genre)
[Termes IGN] politique forestière
[Termes IGN] Quercus (genre)
[Termes IGN] sécheresse
[Termes IGN] tempête
[Termes IGN] Texas (Etats-Unis)
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) Understanding the impacts of large-scale disturbances on forest conditions is necessary to support forest management, planning, and policy decision making. National forest inventories (NFIs) are an important information source that provide consistent data encompassing large areas, covering all ownerships, and extending through time. Here we compare how temporal aggregation approaches with NFI data affects estimates of standing dead trees as these respond to extreme disturbance events. East Texas was selected for this study owing to the occurrence of three significant disturbance events in a short span: Hurricane Rita in 2005, Hurricane Ike in 2008, and a historic drought in 2011. Wide-spread tree damage and mortality were reported after each disturbance and estimates of standing dead trees were used as the inventory variable for assessment. In the NFI of the US, the plot network is systematically divided into panels and one panel is measured each year. A measurement cycle is completed when all panels have been measured, which varies between 5 and 10 years depending on the region. Using the standard estimation approach of the US NFI, we computed population estimates using data from the full set of panels (FSP), multiple sets of panels (MSP), and single set of panels (SSP). For estimation, a single plot observation is computed from the most recent measurement of the plot that does not exceed the estimate year. Because one panel is measured per year, FSP and MSP estimates will necessarily consist of plot observations whose measurements were collected over a number of years. The SSP estimate is computed from one panel and thus all the plot observations are based on measurements collected over one year. We found that interpretations of disturbance event impacts varied depending on which sets of estimates were considered. All sets of estimates suggested a large and significant drought impact. However, differences existed among the estimates in the timing and magnitude of the impacts. The FSP estimates showed clear lag bias and smoothing of trends relative to the SSP estimates. MSP estimates were intermediate between FSP and SSP estimates. Differences in Hurricane Rita impacts were also observed between sets of estimates. Evidence of a net impact on standing dead trees following Hurricane Ike was weak among all sets of estimates. Given the potential for lag bias and smoothing, we recommend that SSP and MSP estimates be considered along with FSP estimates in assessments of large-scale disturbance impacts on forest conditions. Numéro de notice : A2019-483 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2019.01.027 Date de publication en ligne : 28/01/2019 En ligne : https://doi.org/10.1016/j.foreco.2019.01.027 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93659
in Forest ecology and management > vol 437 (1 April 2019) . - pp 27-40[article]Wood quality of black spruce and balsam fir trees defoliated by spruce budworm: A case study in the boreal forest of Quebec, Canada / Carlos Paixao in Forest ecology and management, vol 437 (1 April 2019)
[article]
Titre : Wood quality of black spruce and balsam fir trees defoliated by spruce budworm: A case study in the boreal forest of Quebec, Canada Type de document : Article/Communication Auteurs : Carlos Paixao, Auteur ; Cornelia Krause, Auteur ; Hubert Morin, Auteur ; Alexis Achim, Auteur Année de publication : 2019 Article en page(s) : pp 201-210 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies balsamea
[Termes IGN] biomasse forestière
[Termes IGN] bois sur pied
[Termes IGN] croissance des arbres
[Termes IGN] défoliation
[Termes IGN] densité du bois
[Termes IGN] diamètre des arbres
[Termes IGN] données dendrométriques
[Termes IGN] forêt boréale
[Termes IGN] insecte nuisible
[Termes IGN] Picea mariana
[Termes IGN] qualité du bois
[Termes IGN] Québec (Canada)
[Termes IGN] télédétection aérienneRésumé : (auteur) Spruce budworm (SBW – Choristoneura fumiferana Clem.) is one of the most damaging defoliating insects in the coniferous forests of eastern North America. In Canada, the widely distributed balsam fir (Abies balsamea L. (Mill)) and black spruce (Picea mariana B.S.P. (Mill)) are its most important hosts. Defoliation by SBW reduces growth in the host trees and can lead to host mortality. Although SBW impacts on growth are well documented, much less is known about changes in wood properties resulting from defoliation. To address this knowledge gap, we sampled 36 SBW-infested stands located in the boreal forest of Quebec (Canada) to determine whether defoliation modifies the wood quality of affected trees. The selected stands had been subjected to one to four years of SBW defoliation. For both species, we assessed ring growth, wood density, and the anatomical characteristics of stem wood formed during the outbreak years. We determined that rings formed during the SBW outbreak had a significant and progressive loss of biomass production with a longer duration of defoliation. SBW significantly reduced latewood density in the second and third year of defoliation for black spruce and the third and fourth year for balsam fir. Average ring density was reduced only in black spruce and only after four years of defoliation. The observed changes in growth and density were associated with changes in anatomical features. While the cellular characteristics of the earlywood remained fairly constant, significant reductions occurred in latewood cell-wall thickness after three years of defoliation. Our study shows that not only do SBW outbreaks reduce annual radial growth, but the cellular characteristics in latewood cells are also modified momentarily. Thus, SBW outbreaks affect wood density and quality in both black spruce and balsam fir. Numéro de notice : A2019-484 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.foreco.2019.01.032 Date de publication en ligne : 01/02/2019 En ligne : https://doi.org/10.1016/j.foreco.2019.01.032 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93661
in Forest ecology and management > vol 437 (1 April 2019) . - pp 201-210[article]A time‐geographic approach to quantifying wildlife–road interactions / Rebecca W. Loraamm in Transactions in GIS, vol 23 n° 1 (February 2019)
[article]
Titre : A time‐geographic approach to quantifying wildlife–road interactions Type de document : Article/Communication Auteurs : Rebecca W. Loraamm, Auteur ; Joni A. Downs, Auteur ; David Lamb, Auteur Année de publication : 2019 Article en page(s) : pp 70 - 86 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes IGN] analyse spatio-temporelle
[Termes IGN] comportement
[Termes IGN] données GPS
[Termes IGN] échantillonnage de données
[Termes IGN] faune locale
[Termes IGN] gestion de la vie sauvage
[Termes IGN] interaction spatiale
[Termes IGN] migration animale
[Termes IGN] Mustelidae
[Termes IGN] prisme spatio-temporel
[Termes IGN] route
[Termes IGN] Time-geography
[Termes IGN] voxelRésumé : (auteur) Recent advances in time geography offer new perspectives for studying animal movements and interactions in an environmental context. In particular, the ability to estimate an animal's spatial location probabilistically at temporal sampling intervals between known fix locations allows researchers to quantify how individuals interact with one another and their environment on finer temporal and spatial scales than previously explored. This article extends methods from time geography, specifically probabilistic space–time prisms, to quantify and summarize animal–road interactions toward understanding related diurnal movement behaviors, including road avoidance. The approach is demonstrated using tracking data for fishers (Martes pennanti) in New York State, where the total probability of interaction with roadways is calculated for individuals over the duration tracked. Additionally, a summarization method visualizing daily interaction probabilities at 60 s intervals is developed to assist in the examination of temporal patterns associated with fishers’ movement behavior with respect to roadways. The results identify spatial and temporal patterns of fisher–roadway interaction by time of day. Overall, the methodologies discussed offer an intuitive means to assess moving object location probabilities in the context of environmental factors. Implications for movement ecology and related conservation planning efforts are also discussed. Numéro de notice : A2019-090 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/tgis.12497 Date de publication en ligne : 17/12/2018 En ligne : https://doi.org/10.1111/tgis.12497 Format de la ressource électronique : url Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92237
in Transactions in GIS > vol 23 n° 1 (February 2019) . - pp 70 - 86[article]Biodiversity response to forest structure and management: Comparing species richness, conservation relevant species and functional diversity as metrics in forest conservation / Chiara Lelli in Forest ecology and management, vol 432 (15 January 2019)PermalinkThis is my spot: characteristics of trees bearing Black Woodpecker cavities / Camille Puverel (2019)PermalinkVisual exploration of migration patterns in gull data / Maximilian Konzack in Information visualization, vol 18 n° 1 (January 2019)PermalinkDigital aerial photogrammetry for assessing cumulative spruce budworm defoliation and enhancing forest inventories at a landscape-level / Tristan R.H. Goodbody in ISPRS Journal of photogrammetry and remote sensing, vol 142 (August 2018)PermalinkEst-il possible de tirer des enseignements des introductions anciennes d'agents pathogènes ? L'exemple de la graphiose de l'orme / Dominique Piou in Revue forestière française, vol 70 n° 6 (2018)PermalinkValidity of historical volunteered geographic information: Evaluating citizen data for mapping historical geographic phenomena / Guiming Zhang in Transactions in GIS, vol 22 n° 1 (February 2018)PermalinkDéveloppement et mise en ligne d’un portail cartographique pour la continuité écologique / Juliette Delannoy (2018)PermalinkMapping grassland management intensity using Sentinel-2 satellite data / Marijke Elisabeth Bekkema in GI Forum, vol 2018 n° 1 ([01/01/2018])PermalinkRemotely sensed forest habitat structures improve regional species conservation / Christian Reichsteiner in Remote sensing in ecology and conservation, vol 3 n° 4 (December 2017)PermalinkHabitat connectivity affects specialist species richness more than generalists in veteran trees / Anne Sverdrup-Thygeson in Forest ecology and management, vol 403 (1 November 2017)Permalink