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Detection and biomass estimation of phaeocystis globosa blooms off Southern China from UAV-based hyperspectral measurements / Xue Li in IEEE Transactions on geoscience and remote sensing, vol 60 n° 1 (January 2022)
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Titre : Detection and biomass estimation of phaeocystis globosa blooms off Southern China from UAV-based hyperspectral measurements Type de document : Article/Communication Auteurs : Xue Li, Auteur ; Shaoling Shang, Auteur ; Zhongping Lee, Auteur ; et al., Auteur Année de publication : 2022 Article en page(s) : n° 4200513 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] algue
[Termes IGN] biomasse
[Termes IGN] cartographie thématique
[Termes IGN] Chine
[Termes IGN] chlorophylle
[Termes IGN] couleur de l'océan
[Termes IGN] espèce exotique envahissante
[Termes IGN] image captée par drone
[Termes IGN] image hyperspectrale
[Termes IGN] plancton
[Termes IGN] réflectanceRésumé : (auteur) Phaeocystis globosa (P. globosa) is a unique causative species of harmful algal blooms, which can form gelatinous colonies. We, for the first time, used unmanned aerial vehicle (UAV) measurements to identify P. globosa blooms and to quantify the biomass. Based on in situ measured remote sensing reflectance ( Rrs ), it is found that, for P. globosa blooms, the maximum of the second-derivative ( dλ2Rrs ) of Rrs(λ) in the 460–480-nm domain is beyond 466 nm. An analysis of the absorption properties from algal cultures suggested that this feature comes from the absorption of chlorophyll c3 (Chl −/c3 ) around 466 nm, a prominent feature of P. globosa. This position of dλ2Rrs maximum was, thus, selected as the criterion for P. globosa identification. The spatial extent of P. globosa blooms in two bays off southern China was then mapped by applying the criterion to UAV-measured Rrs . Twelve out of 16 UAV and in situ match-up stations were consistently identified as dominated by P. globosa, indicating the accuracy of 75%. Furthermore, using localized empirical models, chlorophyll a (Chl −/a ) concentration and colony numbers of P. globosa were estimated from UAV-derived Rrs , where P. globosa colonies were found in a range of ~3–37 gel matrix/L, indicating the occurrence of weak to moderate P. globosa blooms during the surveys. The promising results suggest a high potential for detection and quantification of P. globosa blooms in near-shore bays or harbors using UAV-based hyperspectral remote sensing, where conventional ocean color satellite remote sensing runs into difficulties. Numéro de notice : A2022-025 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1109/TGRS.2021.3051466 Date de publication en ligne : 26/01/2021 En ligne : https://doi.org/10.1109/TGRS.2021.3051466 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99254
in IEEE Transactions on geoscience and remote sensing > vol 60 n° 1 (January 2022) . - n° 4200513[article]Forest inventory-based assessments of the invasion risk of Pseudotsuga menziesii (Mirb.) Franco and Quercus rubra L. in Germany / A. Bindewald in European Journal of Forest Research, vol 140 n° 4 (August 2021)
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Titre : Forest inventory-based assessments of the invasion risk of Pseudotsuga menziesii (Mirb.) Franco and Quercus rubra L. in Germany Type de document : Article/Communication Auteurs : A. Bindewald, Auteur ; S. Miocic, Auteur ; A. Wedler, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 883 - 899 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] écosystème forestier
[Termes IGN] espèce exotique envahissante
[Termes IGN] gestion forestière
[Termes IGN] habitat forestier
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] Pseudotsuga menziesii
[Termes IGN] Quercus rubra
[Termes IGN] régénération (sylviculture)
[Termes IGN] zone tampon
[Vedettes matières IGN] Inventaire forestierRésumé : (auteur) In Europe, some non-native tree species (NNT) are classified as invasive because they have spread into semi-natural habitats. Yet, available risk assessment protocols are often based on a few limited case studies with unknown representativeness and uncertain data quality. This is particularly problematic when negative impacts of NNT are confined to particular ecosystems or processes, whilst providing valuable ecosystem services elsewhere. Here, we filled this knowledge gap and assessed invasion risks of two controversially discussed NNT in Germany (Quercus rubra L., Pseudotsuga menziesii (Mirb.) Franco) for broad forest types using large scale inventory data. For this purpose, establishment success of natural regeneration was quantified in terms of cover and height classes. The current extent of spread into protected forest habitats was investigated in south-west Germany using regional data. Establishment was most successful at sites where the NNT are abundant in the canopy and where sufficient light is available in the understory. Natural regeneration of both NNT was observed in 0.3% of the total area of protected habitats. In forest habitats with sufficient light in the understory and competitively inferior tree species, there is a risk that Douglas fir and red oak cause changes in species composition in the absence of management interventions. The installation of buffer zones and regular removal of unwanted regeneration could minimize such risks for protected areas. Our study showed that forest inventories can provide valuable data for comparing the establishment risk of NNT amongst ecosystem types, regions or jurisdictions. This information can be improved by recording the abundance and developmental stage of widespread NNT, particularly in semi-natural ecosystems. Numéro de notice : A2021-718 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s10342-021-01373-0 En ligne : https://doi.org/10.1007/s10342-021-01373-0 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=98635
in European Journal of Forest Research > vol 140 n° 4 (August 2021) . - pp 883 - 899[article]Improving the unsupervised mapping of riparian bugweed in commercial forest plantations using hyperspectral data and LiDAR / Kabir Peerbhay in Geocarto international, vol 36 n° 4 ([01/03/2021])
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Titre : Improving the unsupervised mapping of riparian bugweed in commercial forest plantations using hyperspectral data and LiDAR Type de document : Article/Communication Auteurs : Kabir Peerbhay, Auteur ; Onisimo Mutanga, Auteur ; Romano Lottering, Auteur ; et al., Auteur Année de publication : 2021 Article en page(s) : pp 465 - 480 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] carte de la végétation
[Termes IGN] classification non dirigée
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] détection d'objet
[Termes IGN] données lidar
[Termes IGN] espèce exotique envahissante
[Termes IGN] forêt ripicole
[Termes IGN] image AISA+
[Termes IGN] image hyperspectrale
[Termes IGN] précision cartographique
[Termes IGN] semis de pointsRésumé : (auteur) Accurate spatial information on the location of invasive alien plants (IAPs) in riparian environments is critical to fulfilling a comprehensive weed management regime. This study aimed to automatically map the occurrence of riparian bugweed (Solanum mauritianum) using airborne AISA Eagle hyperspectral data (393 nm–994 nm) in conjunction with LiDAR derived height. Utilising an unsupervised random forest (RF) classification approach and Anselin local Moran’s I clustering, results indicate that the integration of LiDAR with minimum noise fraction (MNF) produce the best detection rate (DR) of 88%, the lowest false positive rate (FPR) of 7.14% and an overall mapping accuracy of 83% for riparian bugweed. In comparison, utilising the original hyperspectral wavebands with and without LiDAR produced lower DRs and higher FPRs with overall accuracies of 79% and 68% respectively. This research demonstrates the potential of combining spectral information with LiDAR to accurately map IAPs using an automated unsupervised RF anomaly detection framework. Numéro de notice : A2021-163 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2019.1614101 Date de publication en ligne : 10/06/2019 En ligne : https://doi.org/10.1080/10106049.2019.1614101 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97084
in Geocarto international > vol 36 n° 4 [01/03/2021] . - pp 465 - 480[article]Range-wide demographic patterns in European forests along climatic marginality gradients : An approach using national forest inventories / Alexandre Changenet (2021)
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Titre : Range-wide demographic patterns in European forests along climatic marginality gradients : An approach using national forest inventories Type de document : Thèse/HDR Auteurs : Alexandre Changenet, Auteur ; Marta Benito-Garzon, Directeur de thèse ; Annabel J. Porté, Directeur de thèse Editeur : Bordeaux : Université de Bordeaux Année de publication : 2021 Importance : 305 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse présentée pour obtenir le grade de Docteur de l'Université de Bordeaux, Ecologie évolutive, fonctionnelle et des communautésLangues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] changement climatique
[Termes IGN] écologie forestière
[Termes IGN] écosystème forestier
[Termes IGN] Espagne
[Termes IGN] espèce exotique envahissante
[Termes IGN] Finlande
[Termes IGN] gradient de marginalité climatique
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] mortalité
[Termes IGN] Quercus rubra
[Termes IGN] répartition géographique
[Termes IGN] Robinia pseudoacacia
[Termes IGN] sécheresse
[Termes IGN] Suède
[Termes IGN] Wallonie (Belgique)
[Vedettes matières IGN] Inventaire forestierIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Modern climate change is reshaping species distributions, particularly on slow shifting organisms such as trees. Forests composition is therefore expected to change in the coming decades, which will alter ecosystem functions and biodiversity, with negative ecological and societal consequences for the planet.Tree distribution depends on several demographic traits such as recruitment, growth and mortality that interact across large climatic gradients. Yet, mortality is rising in all forested biomes in the world. In Europe for instance, forest mortality increases towards the climatic trailing edge of the species ranges as a response to drought. These high mortality rates are usually related to a lack of recruitment, which may induce vegetation shifts, but also opening new opportunities for the establishment of exotic invasive species. As demographic trait responses to climate vary across and within species, understanding trait interactions along large climatic gradients is crucial to better predict the impact of climate change on forest productivity, composition and range-shift dynamics.In this work I analyzed tree mortality and recruitment patterns of twenty of the most common native species and two exotic species in European forests and their triggered drivers. To this aim, I used data of 2 million trees from 153 892 plots measured in the National Forest Inventories from France, Spain, Germany, Belgium (Wallonia), Sweden and Finland.In the first chapter, I analyzed tree mortality and showed that the highest mortality occurrence happens in the climatic trailing edge, driven by drought, whereas the intensity of mortality is triggered by competition, drought and high temperatures and was uniformly scattered across species ranges. In addition, the occurrence of mortality was the highest in the trailing edge of temperate species and the lowest in the leading edge for half of the Mediterranean species.In the second chapter I analyzed tree recruitment, showing that for most species, there are no differences in recruitment across species ranges. Recruitment was strongly limited by competition and often depended on age, or growth rate of the plot. Surprisingly, the role of drought in tree recruitment only was evident in interaction with tree competition.In the third chapter, I assessed the invasiveness of two exotic invasive species, Quercus rubra and Robinia pseudoacacia. My results showed that both species are able to recruit new individuals under all other species canopies, to become dominant at the expanse of many trees species and suggested that they are both expanding their ranges northwards and southwards, in part because they are relatively less sensitive to drought than the other species.All together, my results highlight that trees sensitivity to current climate change is trait-dependent and differs across species ranges. The southern part of the species ranges can be shaped by drought-induced mortality, while recruitment is much less affected by drought. This different sensitivity to climate of tree mortality and recruitment suggests that recruitment could counteract the negative effects of climate change to a certain extent and that forests might be more resilient than what was previously thought. Yet, the exotic species expansion is less affected by the surrounding environment than Mediterranean and temperate species and could benefit from climate warming. Hence, the potential help of recruitment for in-situ species range persistence, and the management strategies which could help forests to mitigate future climate change remains to be explored. Note de contenu : 1- Introduction
2- Methods
3- Occurence but not intensity of mortality rises towards the climatic trailing edge of tree species ranges in European forests
4- Recruitment in European forests is more limited by competition than drought
5- Increase of invasiveness of Quercus rubra and Robinia pseudoacacia in European forests: an approach using National Forest Inventories
6- General discussion and conclusionNuméro de notice : 28483 Affiliation des auteurs : non IGN Thématique : FORET Nature : Thèse française Note de thèse : Thèse de Doctorat : Ecologie évolutive, fonctionnelle et des communautés : Bordeaux : 2021 Organisme de stage : Laboratoire Biodiversité, Gènes & Communautés DOI : sans En ligne : https://tel.archives-ouvertes.fr/tel-03462635/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99187 Using remote sensing and modeling to monitor and understand harmful algal blooms. Application to Karaoun Reservoir (Lebanon) / Najwa Sharaf (2021)
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Titre : Using remote sensing and modeling to monitor and understand harmful algal blooms. Application to Karaoun Reservoir (Lebanon) Type de document : Thèse/HDR Auteurs : Najwa Sharaf, Auteur ; Brigitte Vinçon-Leite, Directeur de thèse ; Kamal Slim, Directeur de thèse Editeur : Paris : Ecole Nationale des Ponts et Chaussées ENPC Année de publication : 2021 Importance : 132 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de Doctorat Sciences et Techniques de l’environnementLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] algue
[Termes IGN] barrage
[Termes IGN] chlorophylle
[Termes IGN] distribution spatiale
[Termes IGN] espèce exotique envahissante
[Termes IGN] hydrodynamique
[Termes IGN] image Landsat-8
[Termes IGN] image Sentinel-MSI
[Termes IGN] lac
[Termes IGN] Liban
[Termes IGN] modélisation 3D
[Termes IGN] plancton
[Termes IGN] simulation hydrodynamique
[Termes IGN] température de surfaceIndex. décimale : THESE Thèses et HDR Résumé : (auteur) Reservoirs are strategic water resources in particular for drinking water and hydropower production. Nevertheless, their physical and biogeochemical processes have been long influenced by anthropogenic pressures. A complete and regular monitoring of reservoir water quality in the context of current climate change, eutrophication and higher water demand, has become crucial for optimal management strategies. Recent progress in the satellite remote sensing field made it possible to enhance data acquisition on a synoptic scale and to perform retrospective studies. Satellite data can complement measurements however over a limited depth of the water column. In addition, three-dimensional (3D) numerical models which integrate physical, chemical and biological processes can fill temporal gaps and extend the information into the vertical domain.In this context, this PhD thesis focuses on the combined use of techniques and data derived from field monitoring, satellite remote sensing and 3D modeling. The overreaching objective of this work is to propose a combined approach for surveying the water quality of medium-sized reservoirs (~ 14 km2).The study site is Karaoun Reservoir, Lebanon (semi-arid climate, surface 12 km2, capacity 110 hm3). It mainly serves for hydropower however with possibly a future drinking water production. It is eutrophic and has been experiencing regular events of toxic cyanobacterial blooms. The following methodological approach was adopted:i) In situ measurements were regularly collected from spring to fall for the calibration and the validation of remote sensing algorithms and of the model.ii) In order to calibrate and validate remote sensing algorithms, Landsat 8 and Sentinel-2 imagery were atmospherically corrected using a single-channel algorithm and the 6SV code respectively.a. Four algorithms from literature for deriving surface temperature were validated using Landsat 8 thermal data.b. A previously calibrated and validated Sentinel-2 algorithm was applied to retrieve chlorophyll-a concentrations.c. An empirical algorithm was calibrated and validated in order to retrieve transparency from Sentinel-2 data.iii) In order to conduct a retrospective analysis of surface temperature, the validated single channel algorithm was applied to a series of Landsat images from 1984 to 2018.iv) In order to reproduce the hydrodynamics and ecological processes, including cyanobacterial biomass in space and time, the Delft3D model was configured, calibrated and validated for summer and fall. The spatial distribution of surface temperature and chlorophyll-a concentrations from the satellite and the model were investigated.The results of this study revealed that, among the four tested algorithms, the single channel algorithm dependent on atmospheric water vapor content and lake water emissivity yielded the best estimations of surface temperature. Using this validated algorithm, the retrospective analysis of surface temperature did not reveal any warming trend over the 1984-2018 period at the study site. Compared to in situ profiles, the Delft3D model represented well the evolution of the water level fluctuations, and the time and vertical distribution of temperature and phytoplankton biomass. Satellite data and model simulations showed minor spatial heterogeneities of surface temperature ( Note de contenu : General introduction
1- State of the art
2- Materials and methods
3- Field data analysis
4- Lake surface temperature retrieval from Landsat-8 and retrospective analysis
5- Thermal regime of reservoirs: A satellite and 3D modeling approach
6- 3D ecological modeling at Karaoun Reservoir
7- Conclusions and perspectivesNuméro de notice : 28499 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Sciences et Techniques de l’environnement : Ponts ParisTech : 2021 Organisme de stage : Laboratoire Eau Environnement et Systèmes Urbains DOI : sans En ligne : https://pastel.archives-ouvertes.fr/tel-03404563 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99311 Convolutional Neural Networks accurately predict cover fractions of plant species and communities in Unmanned Aerial Vehicle imagery / Teja Kattenborn in Remote sensing in ecology and conservation, vol 6 n° 4 (December 2020)
PermalinkDevelopment and application of a new mangrove vegetation index (MVI) for rapid and accurate mangrove mapping / Alvin B. Baloloy in ISPRS Journal of photogrammetry and remote sensing, vol 166 (August 2020)
PermalinkTowards a semi-automated mapping of Australia native invasive alien Acacia trees using Sentinel-2 and radiative transfer models in South Africa / Cecilia Masemola in ISPRS Journal of photogrammetry and remote sensing, vol 166 (August 2020)
PermalinkBiodiversity conservation in cities: Defining habitat analogues for plant species of conservation interest / M. Itani in Plos one, vol 15 n° 6 (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)
PermalinkPermalinkAilanthus altissima mapping from multi-temporal very high resolution satellite images / Cristina Tarantino in ISPRS Journal of photogrammetry and remote sensing, vol 147 (January 2019)
PermalinkPermalinkIntra-annual phenology for detecting understory plant invasion in urban forests / Kunwar K. Singh in ISPRS Journal of photogrammetry and remote sensing, vol 142 (August 2018)
PermalinkMulti-scale assessment of invasive plant species diversity using Pléiades 1A, RapidEye and Landsat-8 data / Siddhartha Khare in Geocarto international, vol 33 n° 7 (July 2018)
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