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Factors affecting winter damage and recovery of newly planted Norway spruce seedlings in boreal forests / Jaana Luoranen in Forest ecology and management, vol 503 (January-1 2022)
[article]
Titre : Factors affecting winter damage and recovery of newly planted Norway spruce seedlings in boreal forests Type de document : Article/Communication Auteurs : Jaana Luoranen, Auteur ; Johanna Riikonen, Auteur ; Timo Saksa, Auteur Année de publication : 2022 Article en page(s) : n° 119759 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] coupe rase (sylviculture)
[Termes IGN] dommage forestier causé par facteurs naturels
[Termes IGN] Finlande
[Termes IGN] forêt boréale
[Termes IGN] hiver
[Termes IGN] phénomène météorologique
[Termes IGN] Picea abies
[Termes IGN] régénération (sylviculture)
[Termes IGN] semis (sylviculture)
[Termes IGN] stockage
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) In boreal and temperate forest zones, snowless winters and springs with varying temperature conditions are becoming more common with climate change. In the spring of 2020, extensive winter damage in Norway spruce (Picea abies (L.) Karst.) seedlings, which had been planted the previous year in Central Finland, was observed. In most cases, the probable reason was winter desiccation. This provided a good opportunity to study the regeneration site, seedling, and weather factors that affect winter damage and the recovery of seedlings from damage. In the study, systematic plot sampling was done in 60 selected regeneration sites where damage was known to have occurred. The prediction models for the probabilities of winter damage and the recovery of seedlings were fit to the data. The risk of winter damage was higher in seedlings packed in a closed package than in seedlings stored in open trays. The risk was especially high if seedlings packed in a closed package were stored for more than a week before planting in the middle of June or later. In open trays, the risk of damage was highest in seedlings planted in September, but even then, the risk was lower than in seedlings packed in a closed package. Long storage duration also increased the damage risk in seedlings stored in open trays and planted in September. Other factors that increased damage were coarse soil and the sample plot being on top of a hill. Factors reducing the risk were a fast chain from clear-cutting to planting, planting in good-quality mounds, a sample plot position on the north slope, and the shading of the forest edge on the southern side of a plot. Recovery of seedlings was weaker when seedlings were stored in a closed package and planted in the fall, in too shallow planting depth, or in humus-covered mounds. Recovery improved when seedlings were planted at a depth of at least 5 cm, or when the coniferous forest edge was on the southern or western side of a plot. Winter damage reduced seedling growth and induced the formation of multiple leaders. In practice, the most important factors to be taken into account were avoiding long storage duration and planting seedlings packed in a closed package after the middle of June. Good-quality site preparation and planting were also important for minimizing the risk of damage and improving recovery. Numéro de notice : A2022-011 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2021.119759 Date de publication en ligne : 07/10/2021 En ligne : https://doi.org/10.1016/j.foreco.2021.119759 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=99068
in Forest ecology and management > vol 503 (January-1 2022) . - n° 119759[article]Assessment of winter season land surface temperature in the Himalayan regions around the Kullu area in India using Landsat-8 data / Divyesh Varade in Geocarto international, vol 35 n° 6 ([01/05/2020])
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Titre : Assessment of winter season land surface temperature in the Himalayan regions around the Kullu area in India using Landsat-8 data Type de document : Article/Communication Auteurs : Divyesh Varade, Auteur ; Onkar Dikshit, Auteur Année de publication : 2020 Article en page(s) : pp 641 - 662 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] emissivité
[Termes IGN] Himalaya
[Termes IGN] hiver
[Termes IGN] image Landsat-8
[Termes IGN] image multibande
[Termes IGN] image Sentinel-3
[Termes IGN] Inde
[Termes IGN] manteau neigeux
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] précision de détermination de surface
[Termes IGN] seuillage
[Termes IGN] température au solRésumé : (auteur) In this study, we propose a modified thresholds method for the determination of land surface emissivity (LSE) for snow covered mountainous areas. The conventional Normalized Differenced Vegetation Index (NDVI) thresholds method (NDVITHM) does not discriminate the snow covered pixels with soil pixels in assigning the LSE based on NDVI thresholds. In the proposed approach, we incorporate different thresholding rules based on the Normalized Differenced Snow Index and the S3 index for incorporating separability in the LSE for the snow covered pixels. The LSE thus derived is used to determine the land surface temperature using the Single Channel Method. The approach was evaluated for a study area around the Kullu Valley in the lower Indian Himalayas for a dataset of the winter season of Landsat-8 multispectral data. The observed coefficient of determination values indicated that the proposed method yielded better results with respect to the conventional NDVITHM approach. Numéro de notice : A2020-203 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1080/10106049.2018.1520928 Date de publication en ligne : 26/12/2018 En ligne : https://doi.org/10.1080/10106049.2018.1520928 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94878
in Geocarto international > vol 35 n° 6 [01/05/2020] . - pp 641 - 662[article]Techniques for efficient detection of rapid weather changes and analysis of their impacts on a highway network / Adil Alim in Geoinformatica, vol 24 n° 2 (April 2020)
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Titre : Techniques for efficient detection of rapid weather changes and analysis of their impacts on a highway network Type de document : Article/Communication Auteurs : Adil Alim, Auteur ; Aparna Joshi, Auteur ; Feng Chen, Auteur ; Catherine T. Lawson, Auteur Année de publication : 2020 Article en page(s) : pp 269 – 299 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] corrélation
[Termes IGN] détection d'événement
[Termes IGN] détection de changement
[Termes IGN] données spatiotemporelles
[Termes IGN] entretien du réseau
[Termes IGN] hiver
[Termes IGN] météorologie
[Termes IGN] prévision météorologique
[Termes IGN] réseau routier
[Termes IGN] sécurité routière
[Termes IGN] trafic routierRésumé : (auteur) Adverse weather conditions have a significant impact on the safety, mobility, and efficiency of highway networks. Weather contributed to 23 percent of all non-reoccurring delay and approximately 544 million vehicle hours of delay each year (2014). Nearly 2.3 billion dollars each year are spent by transportation agencies for winter maintenance that contribute to close to 20 percent of most DOT’s yearly budgets (2014). These safety and mobility factors make it important to develop new and more effective methods to address road conditions during adverse weather conditions. Given weather and traffic sensors installed along side of the highway networks, how can we automatically detect weather and traffic change events and prevent from the traffic delay or harsh weather accidents? To this end, we propose a novel framework to address this problem. This paper develops techniques for efficiently detecting rapid weather change events and analyzing their impacts on the traffic flow characteristics of a highway network. It is composed of three components, including 1) detection of rapid weather change events in a highway network using the streaming weather information from a sensor network of weather stations; 2) detection of rapid traffic change events on the traffic flow characteristics (e.g., travel time) of the highway network; and 3) analysis of correlations between the detected weather and traffic change events in space and time. The proposed approach was applied to a weather dataset provided by New York State Mesonet and a traffic flow dataset the National Performance Management Research Data Set (NPMRDS) provided by NYSDOT. The empirical results provide potential evidence about the significant impacts of rapid weather change events on traffic flow characteristics of the Interstate 90 (I-90) Highway in the state of New York. We show the quantitative performance evaluation of our change event detection algorithm and three baseline methods on manually labeled the weather dataset and our method outperforms baselines in terms of precision, recall and F-score. We present the analysis of Top K detected change events as case studies and also provide the spatio-temporal correlation statistics of top k weather and traffic change events. The limitations of the proposed approach and the empirical study are also discussed. Numéro de notice : A2020-358 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s10707-020-00395-x Date de publication en ligne : 12/02/2020 En ligne : https://doi.org/10.1007/s10707-020-00395-x Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95263
in Geoinformatica > vol 24 n° 2 (April 2020) . - pp 269 – 299[article]Forest gaps retard carbon and nutrient release from twig litter in alpine forest ecosystems / Bo Tan in European Journal of Forest Research, vol 139 n° 1 (February 2020)
[article]
Titre : Forest gaps retard carbon and nutrient release from twig litter in alpine forest ecosystems Type de document : Article/Communication Auteurs : Bo Tan, Auteur ; Jian Zhang, Auteur ; Wanqin Yang, Auteur ; et al., Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] azote
[Termes IGN] carbone
[Termes IGN] Chine
[Termes IGN] dégel
[Termes IGN] écosystème forestier
[Termes IGN] forêt alpestre
[Termes IGN] gelée
[Termes IGN] hiver
[Termes IGN] litière
[Termes IGN] nutriment végétal
[Termes IGN] phosphore
[Termes IGN] température au sol
[Vedettes matières IGN] BotaniqueRésumé : (auteur) Changes in soil microclimate driven by forest gaps have accelerated mass loss and carbon (C), nitrogen (N) and phosphorus (P) release from foliar litter in alpine forests ecosystems. Yet, it is unclear whether the same gap effect occurs in twig litter decomposition. A 4-year decomposition experiment was conducted in an alpine forest to explore the litter mass loss and C, N and P release among four gap treatments, including (1) closed canopy, (2) small gap ( Numéro de notice : A2020-229 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s10342-019-01229-8 Date de publication en ligne : 12/09/2019 En ligne : https://doi.org/10.1007/s10342-019-01229-8 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94966
in European Journal of Forest Research > vol 139 n° 1 (February 2020)[article]Evaluation of time-series SAR and optical images for the study of winter land-use / Julien Denize (2019)
Titre : Evaluation of time-series SAR and optical images for the study of winter land-use Type de document : Thèse/HDR Auteurs : Julien Denize, Auteur ; Eric Pottier, Directeur de thèse ; Laurence Hubert-Moy, Directeur de thèse Editeur : Rennes : Université de Rennes 1 Année de publication : 2019 Importance : 274 p. Format : 21 x 30 cm Note générale : bibliographie
Thèse de Doctorat de l'Université Rennes 1, Mathématiques et Sciences et Technologies de l'Information et de la Communication, Spécialité Signal Image Vision & GéomatiqueLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image mixte
[Termes IGN] agriculture
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] données polarimétriques
[Termes IGN] hiver
[Termes IGN] image à haute résolution
[Termes IGN] image radar moirée
[Termes IGN] image Radarsat
[Termes IGN] image Sentinel-MSI
[Termes IGN] image Sentinel-SAR
[Termes IGN] nébulosité
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] série temporelle
[Termes IGN] télédétection spatiale
[Termes IGN] utilisation du solIndex. décimale : THESE Thèses et HDR Résumé : (auteur) The study of winter land-use is a major challenge in order to preserve and improve the quality of soils and surface water. However, knowledge of the spatio-temporal dynamics associated with winter land-use remains a challenge for the scientific community. In this context, the objective of this study is to evaluate the potential of time series of high spatial resolution optical and SAR images for the study of winter land-use at a local and regional scale. For that purpose, a methodology has been established to: (i) determine the most suitable classification method for identifying winter land-use ; (ii) compare Sentinel-1 SAR and Sentinel-2 optical images; (iii) define the most suitable SAR configuration by comparing three image time-series (Alos-2, Radarsat-2 and Sentinel-1).The results first of all highlighted the interest of the Random Forest classification algorithm to discriminate at a fine scale the different types of land use in winter. Secondly, they showed the value of Sentinel-2 data for mapping winter land-use at a local and regional scale. Finally, they determined that a dense time series of Sentinel-1 images was the most appropriate SAR configuration to identify winter land-use. In general, while this thesis has shown that Sentinel-2 data are best suited to studying land use in winter, SAR images are of great interest in regions with significant cloud cover, dense Sentinel-1 time-series having being defined as the most efficient. Note de contenu : General Introduction
1- Winter land-use: concepts, data and methods
2- Classification procedure for the winter land-use study at a local scale
3- SAR configuration for the study of winter land-use at a local scale
4- The study of winter land-use at a regional scale
General conclusion and perspectivesNuméro de notice : 25710 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Thèse française Note de thèse : Thèse de Doctorat : Signal Image Vision & Géomatique : Rennes1 : 2019 Organisme de stage : Institut d’Electronique et de Télécommunication de Rennes nature-HAL : Thèse DOI : sans En ligne : https://hal.science/tel-02510333/document Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=94858 Estimation of winter wheat crop growth parameters using time series Sentinel-1A SAR data / P. Kumar in Geocarto international, vol 33 n° 9 (September 2018)PermalinkAutomatic segment-level tree species recognition using high resolution aerial winter imagery / Anton Kuzmin in European journal of remote sensing, vol 49 n° 1 (2016)PermalinkImproving winter leaf area index estimation in coniferous forests and its significance in estimating the land surface albedo / Rong Wang in ISPRS Journal of photogrammetry and remote sensing, vol 119 (September 2016)Permalink