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Early detection of forest stress from European spruce bark beetle attack, and a new vegetation index: Normalized distance red & SWIR (NDRS) / Langning Huo in Remote sensing of environment, Vol 255 (March 2021)
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Titre : Early detection of forest stress from European spruce bark beetle attack, and a new vegetation index: Normalized distance red & SWIR (NDRS) Type de document : Article/Communication Auteurs : Langning Huo, Auteur ; Henrik J. Persson, Auteur ; Eva Lindberg, Auteur Année de publication : 2021 Article en page(s) : n° 112240 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes descripteurs IGN] bande infrarouge
[Termes descripteurs IGN] écho radar
[Termes descripteurs IGN] houppier
[Termes descripteurs IGN] image Sentinel-MSI
[Termes descripteurs IGN] image Sentinel-SAR
[Termes descripteurs IGN] indice de stress
[Termes descripteurs IGN] indice de végétation
[Termes descripteurs IGN] insecte nuisible
[Termes descripteurs IGN] maladie parasitaire
[Termes descripteurs IGN] picea mariana
[Termes descripteurs IGN] scolyte
[Termes descripteurs IGN] signature spectrale
[Termes descripteurs IGN] SuèdeRésumé : (auteur) The European spruce bark beetle (Ips typographus [L.]) is one of the most damaging pest insects of European spruce forests. A crucial measure in pest control is the removal of infested trees before the beetles leave the bark, which generally happens before the end of June. However, stressed tree crowns do not show any significant color changes in the visible spectrum at this early-stage of infestation, making early detection difficult. In order to detect the related forest stress at an early stage, we investigated the differences in radar and spectral signals of healthy and stressed trees. How the characteristics of stressed trees changed over time was analyzed for the whole vegetation season, which covered the period before attacks (April), early-stage infestation (‘green-attacks’, May to July), and middle to late-stage infestation (August to October). The results show that spectral differences already existed at the beginning of the vegetation season, before the attacks. The spectral separability between the healthy and infested samples did not change significantly during the ‘green-attack’ stage. The results indicate that the trees were stressed before the attacks and had spectral signatures that differed from healthy ones. These stress-induced spectral changes could be more efficient indicators of early infestations than the ‘green-attack’ symptoms. In this study we used Sentinel-1 and 2 images of a test site in southern Sweden from April to October in 2018 and 2019. The red and SWIR bands from Sentinel-2 showed the highest separability of healthy and stressed samples. The backscatter from Sentinel-1 and additional bands from Sentinel-2 contributed only slightly in the Random Forest classification models. We therefore propose the Normalized Distance Red & SWIR (NDRS) index as a new index based on our observations and the linear relationship between the red and SWIR bands. This index identified stressed forest with accuracies from 0.80 to 0.88 before the attacks, from 0.80 to 0.82 in the early-stage infestation, and from 0.81 to 0.91 in middle- and late-stage infestations. These accuracies are higher than those attained by established vegetation indices aimed at ‘green-attack’ detection, such as the Normalized Difference Water Index, Ratio Drought Index, and Disease Stress Water Index. By using the proposed method, we highlight the potential of using NDRS with Sentinel-2 images to estimate forest vulnerability to European spruce bark beetle attacks early in the vegetation season. Numéro de notice : A2021-190 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.1016/j.rse.2020.112240 date de publication en ligne : 20/01/2021 En ligne : https://doi.org/10.1016/j.rse.2020.112240 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97111
in Remote sensing of environment > Vol 255 (March 2021) . - n° 112240[article]Geo-spatially modelling dengue epidemics in urban cities: a case study of Lahore, Pakistan / Muhammad Imran in Geocarto international, vol 36 n° 2 ([01/02/2021])
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Titre : Geo-spatially modelling dengue epidemics in urban cities: a case study of Lahore, Pakistan Type de document : Article/Communication Auteurs : Muhammad Imran, Auteur ; Yasra Hamid, Auteur ; Abeer Mazher, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 197 - 211 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] cartographie des risques
[Termes descripteurs IGN] diptère
[Termes descripteurs IGN] image Landsat
[Termes descripteurs IGN] maladie tropicale
[Termes descripteurs IGN] modélisation spatiale
[Termes descripteurs IGN] Normalized Difference Vegetation Index
[Termes descripteurs IGN] Pakistan
[Termes descripteurs IGN] régression géographiquement pondérée
[Termes descripteurs IGN] régression logistique
[Termes descripteurs IGN] risque sanitaire
[Termes descripteurs IGN] série temporelle
[Termes descripteurs IGN] zone intertropicale
[Termes descripteurs IGN] zone urbaineRésumé : (auteur) The study objective is to predict the epidemiological impact of dengue fever arbovirosis in urban tropical areas of Pakistan. To do so, we used the GPS-based data of the Aedes larvae collected during 2014–2015 in Lahore. We developed a Geographically Weighted Logistic Regression (GWLR) model for Geospatially predicting larvae presence or absence in Lahore. Data on rainfall, temperature are included along with time series of the normalized difference vegetation index (NDVI) derived from Landsat imagery. We observed a high spatial variability of the GWLR parameter estimates of these variables in the study area. The GWLR model significantly (R2a = 0.78) explained the presence or absence of Aedes larvae with temperature, rainfall and NDVI variables in South and Southeast of the study area. In the North and North-West, however, GWLR relationships were observed weak in highly populated areas. Interpolating GWLR coefficients generate more accurate maps of Aedes larvae presence or absence. Numéro de notice : A2021-118 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2019.1614100 date de publication en ligne : 10/06/2020 En ligne : https://doi.org/10.1080/10106049.2019.1614100 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96932
in Geocarto international > vol 36 n° 2 [01/02/2021] . - pp 197 - 211[article]Search for top‐down and bottom‐up drivers of latitudinal trends in insect herbivory in oak trees in Europe / Elena Valdés-Correcher in Global ecology and biogeography, vol 30 n° inconnu (2021)
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Titre : Search for top‐down and bottom‐up drivers of latitudinal trends in insect herbivory in oak trees in Europe Type de document : Article/Communication Auteurs : Elena Valdés-Correcher, Auteur ; Xoaquín Moreira, Auteur ; Laurent Augusto, Auteur ; Luc Barbaro, Auteur ; Christophe Bouget, Auteur ; Olivier Bouriaud , Auteur ; et al., Auteur
Année de publication : 2021 Projets : 2-Pas d'info accessible - article non ouvert / Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] biochimie
[Termes descripteurs IGN] dommage forestier causé par facteurs naturels
[Termes descripteurs IGN] Europe (géographie politique)
[Termes descripteurs IGN] feuille (végétation)
[Termes descripteurs IGN] oiseau
[Termes descripteurs IGN] Quercus pedunculata
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Aim : The strength of species interactions is traditionally expected to increase toward the Equator. However, recent studies have reported opposite or inconsistent latitudinal trends in the bottom‐up (plant quality) and top‐down (natural enemies) forces driving herbivory. In addition, these forces have rarely been studied together thus limiting previous attempts to understand the effect of large‐scale climatic gradients on herbivory.
Location : Europe. Time period : 2018–2019. Major taxa studied : Quercus robur.
Methods : We simultaneously tested for latitudinal variation in plant–herbivore–natural enemy interactions. We further investigated the underlying climatic factors associated with variation in herbivory, leaf chemistry and attack rates in Quercus robur across its complete latitudinal range in Europe. We quantified insect leaf damage and the incidence of specialist herbivores as well as leaf chemistry and bird attack rates on dummy caterpillars on 261 oak trees.
Results : Climatic factors rather than latitude per se were the best predictors of the large‐scale (geographical) variation in the incidence of gall‐inducers and leaf‐miners as well as in leaf nutritional content. However, leaf damage, plant chemical defences (leaf phenolics) and bird attack rates were not influenced by climatic factors or latitude. The incidence of leaf‐miners increased with increasing concentrations of hydrolysable tannins, whereas the incidence of gall‐inducers increased with increasing leaf soluble sugar concentration and decreased with increasing leaf C : N ratios and lignins. However, leaf traits and bird attack rates did not vary with leaf damage.
Main conclusions : These findings help to refine our understanding of the bottom‐up and top‐down mechanisms driving geographical variation in plant–herbivore interactions, and indicate the need for further examination of the drivers of herbivory on trees.Numéro de notice : A2021-066 Affiliation des auteurs : LIF+Ext (2020- ) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1111/geb.13244 date de publication en ligne : 31/12/2020 En ligne : https://doi.org/10.1111/geb.13244 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96970
in Global ecology and biogeography > vol 30 n° inconnu (2021)[article]Group diagrams for representing trajectories / Maike Buchin in International journal of geographical information science IJGIS, vol 34 n° 12 (December 2020)
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Titre : Group diagrams for representing trajectories Type de document : Article/Communication Auteurs : Maike Buchin, Auteur ; Bernhard Kilgus, Auteur ; Andrea Kölzsch, Auteur Année de publication : 2020 Article en page(s) : pp 2401 - 2433 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Analyse spatiale
[Termes descripteurs IGN] analyse de groupement
[Termes descripteurs IGN] analyse spatio-temporelle
[Termes descripteurs IGN] approximation
[Termes descripteurs IGN] diagramme
[Termes descripteurs IGN] distance de Fréchet
[Termes descripteurs IGN] données GPS
[Termes descripteurs IGN] géomètrie algorithmique
[Termes descripteurs IGN] itinéraire
[Termes descripteurs IGN] migration animale
[Termes descripteurs IGN] mouvement
[Termes descripteurs IGN] objet mobile
[Termes descripteurs IGN] trajectoireRésumé : (auteur) Given the trajectories of one or several moving groups, we propose a new framework, the group diagram (GD) for representing these. Specifically, we seek a minimal GD as a concise representation of the groups maintaining the spatio-temporal structure of the groups’ movement. A GD is specified by three input values, namely a distance threshold, a similarity measure and a minimality criterion. For several variants of the GD, we give a comprehensive analysis of their computational complexity and present efficient approximation algorithms for their computation. Furthermore, we experimentally evaluate our algorithms on GPS data of migrating geese. Applying the proposed methods on these data sets reveals how the GD concisely represents the movement of the groups. This representation can be used for further analysis and for the formulation of new hypotheses for further ecological research, such as differences in movement patterns of groups on different surfaces or the shift of migration routes over several years. We use different similarity measures to summarize the migration routes of (i) a goose family for one migration period and to summarize (ii) the migration routes of one individual for several migration periods or (iii) the migration routes of several independent individuals for one migration period. Numéro de notice : A2020-690 Affiliation des auteurs : non IGN Thématique : GEOMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/13658816.2019.1684498 date de publication en ligne : 25/11/2019 En ligne : https://doi.org/10.1080/13658816.2019.1684498 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96227
in International journal of geographical information science IJGIS > vol 34 n° 12 (December 2020) . - pp 2401 - 2433[article]Forest clear-cuts as habitat for farmland birds and butterflies / Dafne Ram in Forest ecology and management, vol 473 ([01/10/2020])
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Titre : Forest clear-cuts as habitat for farmland birds and butterflies Type de document : Article/Communication Auteurs : Dafne Ram, Auteur ; Åke Lindström, Auteur ; Lars B. Pettersson, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : 9 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes descripteurs IGN] biodiversité
[Termes descripteurs IGN] coupe rase (sylviculture)
[Termes descripteurs IGN] foresterie
[Termes descripteurs IGN] habitat animal
[Termes descripteurs IGN] oiseau
[Termes descripteurs IGN] surface cultivée
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) The intensification of agriculture has resulted in more homogeneous landscapes and declines of many species associated with farmland or other semi-natural open habitats. In parallel, forestry has also intensified causing declines in many species associated with old-growth forests. While intensive forestry negatively affects forest species, it inadvertently creates new habitats such as clear-cuts, which attracts some farmland species. To understand the potential of clear-cuts as alternative habitat for farmland species, we need to know what makes clear-cuts attractive and whether they are suitable for reproduction and survival. We reviewed literature on the occurrence of farmland birds and butterflies in forest clear-cuts and synthesise the current knowledge on factors and characteristics affecting their occurrence.
Many farmland birds and butterflies do indeed use clear-cuts, and have been found in clear-cuts up to ten years after felling. Clear-cut characteristics of importance include age, size, retention structures, land-use history and landscape composition. However, direct measures of resource abundance such as food and hostplants are often lacking. In addition to the potential benefit of individual clear-cuts, the total clear-cut area in forested regions is often large. Together with the fact that clear-cuts may be occupied by farmland species for several years, the potential of clear-cuts as alternative habitat for farmland biodiversity is substantial. Clear-cuts with a history as meadows, the presence of species of conservation importance, or shorter distance to farmland could for example be motivations for focusing conservation efforts on farmland species instead of forest species. Gaining more knowledge on how farmland species use clear-cuts, and what characteristics they depend on, could help inform management guidelines. We are no advocates for forest clear-cuts, but given their ubiquity in forested landscapes, the potential of clear-cuts as alternative habitats for species suffering from loss of suitable farmland habitats is worth serious attention from a conservation perspective.Numéro de notice : A2020-621 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.foreco.2020.118239 date de publication en ligne : 16/06/2020 En ligne : https://doi.org/10.1016/j.foreco.2020.118239 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96017
in Forest ecology and management > vol 473 [01/10/2020] . - 9 p.[article]Increasing Cervidae populations have variable impacts on habitat suitability for threatened forest plant and lichen species / James D.M. Speed in Forest ecology and management, vol 473 ([01/10/2020])
PermalinkEvaluating the impact of declining tsetse fly (Glossina pallidipes) habitat in the Zambezi valley of Zimbabwe / Farai Matawa in Geocarto international, vol 35 n° 12 ([01/09/2020])
PermalinkIncorporating behavior into animal movement modeling: a constrained agent-based model for estimating visit probabilities in space-time prisms / Rebecca W. Loraamm in International journal of geographical information science IJGIS, vol 34 n° 8 (August 2020)
PermalinkReintroduction of the European bison (Bison bonasus) in central-eastern Europe: a case study / Cathlin M. Lord in International journal of geographical information science IJGIS, vol 34 n° 8 (August 2020)
PermalinkMapping areas of asynchronous‐temporal interaction in animal‐telemetry data / Brendan A. Hoover in Transactions in GIS, Vol 24 n° 3 (June 2020)
PermalinkXylem anatomy of Robinia pseudoacacia L. and Quercus robur L. is differently affected by climate in a temperate alluvial forest / Paola Nola in Annals of Forest Science [en ligne], Vol 77 n° 1 (March 2020)
PermalinkCattle detection and counting in UAV images based on convolutional neural networks / Wen Shao in International Journal of Remote Sensing IJRS, vol 41 n° 1 (01 - 08 janvier 2020)
PermalinkThis is my spot: What are the characteristics of the trees excavated by the Black Woodpecker? A case study in two managed French forests / Camille Puverel in Forest ecology and management, vol 453 (1 December 2019)
PermalinkThe influence of sampling design on spatial data quality in a geographic citizen science project / Greg Brown in Transactions in GIS, Vol 23 n° 6 (November 2019)
PermalinkA 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)
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