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Pyrenean silver fir forests retain legacies of past disturbances and climate change in their growth, structure and composition / Antonio Gazol in Forests, vol 14 n° 4 (April 2023)
[article]
Titre : Pyrenean silver fir forests retain legacies of past disturbances and climate change in their growth, structure and composition Type de document : Article/Communication Auteurs : Antonio Gazol, Auteur ; Ester González-de-Andrés, Auteur ; Michele Colangelo, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n° 713 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies alba
[Termes IGN] croissance des arbres
[Termes IGN] dendrochronologie
[Termes IGN] dépérissement
[Termes IGN] échantillonnage
[Termes IGN] Espagne
[Termes IGN] historique
[Termes IGN] Pyrénées (montagne)
[Termes IGN] sécheresse
[Termes IGN] sous-étage
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Recent drought-induced dieback alters forest dynamics, which are also shaped by past management. In western Pyrenean silver fir (Abies alba) stands, dieback concurs in space and time with the legacies of past management, but the impacts on forest growth, structure and composition are unknown. We aim to disentangle how dieback interacts with the legacies of past human use and modulates the recent dynamics of silver fir forests. To this end, we sampled eleven silver fir forests across wide climatic gradients and included declining and non-declining sites. We measured radial growth, structure, composition, understory cover and type and amount of deadwood. Silver fir growth declines in response to late-summer drought. In declining sites, most defoliated stands showed the lowest silver fir density and were those where growth depended more on water availability. Tree death enhanced the cover of dominant understory plants such as Buxus sempervirens. Past management activities leave an imprint in the growth of silver fir, such as releases due to past logging, but also affect the number of stumps and snags and the current tree density. A more extensive monitoring will be required to fully disentangle the multiple influences of past management legacies and current climate change on forest dynamics. Numéro de notice : A2023-202 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.3390/f14040713 Date de publication en ligne : 30/03/2023 En ligne : https://doi.org/10.3390/f14040713 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103104
in Forests > vol 14 n° 4 (April 2023) . - n° 713[article]Atmospheric water vapor measurement in order to estimate continental precipitation over Algeria region based on the INCT-GNSS network / Abdellaoui Hassen in Bulletin des sciences géographiques, vol 27 n° 1 (2023)
[article]
Titre : Atmospheric water vapor measurement in order to estimate continental precipitation over Algeria region based on the INCT-GNSS network Type de document : Article/Communication Auteurs : Abdellaoui Hassen, Auteur ; Ali Omar Hammou, Auteur ; Soraya Makhlouf, Auteur ; Naima Zaourar, Auteur ; Mohamed Aïssa Meslem, Auteur Année de publication : 2023 Article en page(s) : pp 42 - 47 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de géodésie spatiale
[Termes IGN] Algérie
[Termes IGN] climat méditerranéen
[Termes IGN] données GNSS
[Termes IGN] données météorologiques
[Termes IGN] Méditerranée, mer
[Termes IGN] précipitation
[Termes IGN] teneur en vapeur d'eauRésumé : (auteur) Northern Algeria region is characterized a Mediterranean climate, cold, humid, dry winters and warm summers, same as other countries in the world, and is exposed to desertification problems. Along its coast, the average annual precipitation is 384 mm, so more than 75% of its territory has an annual precipitation lower than 384 mm. This is a global problem that affects a large number of people and land, and is now one of the most important environmental problems in Algeria. The work presented in this paper describe a preliminary study of GNSS meteorology technique based on GNSS positioning and estimation of the tropospheric water vapor quantity based exclusively on the INCT-GNSS network. According to our results, we noted that the integrated content of water vapor is a highly variable parameter that depends on the study region, in our study it is between the South and the North of Algeria, this variation is related to the geographical position in relation to the Mediterranean Sea, as well as the season, noticing that during the winter the quantities of water vapor are low compared to the summer. No relationship could be found between GNSS IWV and precipitation values, except for a significant increase in GNSS IWV that frequently precedes the arrival of precipitation. Improving atmospheric observation techniques and understanding of the key processes of precipitation formation is thus a major challenge for our society. In fact, a better prediction of precipitation would allow bettering anticipating the occurrence of floods and consequently to minimize the damages related to these events. Numéro de notice : A2023-091 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : sans En ligne : https://www.asjp.cerist.dz/en/downArticle/213/27/1/216930 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=103153
in Bulletin des sciences géographiques > vol 27 n° 1 (2023) . - pp 42 - 47[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 253-2023011 RAB Revue Centre de documentation En réserve L003 Disponible Documents numériques
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Atmospheric water vapor measurementAdobe Acrobat PDF Seismic deformation in the Adriatic Sea region / B. Orecchio in Journal of geodynamics, vol 155 (March 2023)
[article]
Titre : Seismic deformation in the Adriatic Sea region Type de document : Article/Communication Auteurs : B. Orecchio, Auteur ; D. Presti, Auteur ; S. Scolaro, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : n°101956 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Géodésie physique
[Termes IGN] Adriatique, mer
[Termes IGN] déformation de la croute terrestre
[Termes IGN] faille géologique
[Termes IGN] forme d'onde
[Termes IGN] histogramme
[Termes IGN] inversion
[Termes IGN] sismologie
[Termes IGN] surveillance géologique
[Termes IGN] tectonique des plaquesRésumé : (auteur) We present an overall analysis of the recent seismic activity occurred in the Adriatic Sea region, a strongly debated sector of the Mediterranean area, where several authors have proposed different models of plate configuration and kinematics. In the past, seismic investigations of this marine area have been strongly hampered by non-optimal network geometries, but data quality increase and recent methodological improvements lay the groundwork to attempt more accurate analyses including proper evaluations of result reliability. On these grounds, we investigated the seismic activity of the last decades by means of new hypocenter locations, waveform inversion focal mechanisms and seismogenic stress fields. We used the Bayloc non-linear probabilistic algorithm to compute hypocenter locations for the most relevant seismic sequences by carefully evaluating location quality and seismolineaments reliability. We also provided an updated database of waveform inversion focal mechanisms including original solutions estimated by applying the waveform inversion method Cut And Paste and data available from official catalogs. Then, focal mechanism solutions have been used to estimate seismogenic stress fields through different inversion algorithms. Seismic results indicate a relevant degree of fragmentation and different patterns of deformation in the Central Adriatic region. In particular, our analyses depicted two NW-SE oriented, adjacent volumes: (i) a pure compressive domain with NNE-trending axis of maximum compression characterizes the northeastern volume where the seismic activity occurs on W-to-NW oriented seismic sources; (ii) a transpressive domain with NW-trending axis of maximum compression characterizes the southwestern sector where thrust faulting preferentially occurs on ENE-to-NE oriented planes and strike-slip faulting on E-W ones. Joint evaluation of seismic findings of the present study and kinematic models proposed in the literature indicates just in the Central Adriatic region the presence of a broad deformation zone, accommodating a still evolving fragmentation of the Adriatic domain in two blocks rotating in opposite directions. On these grounds, the obtained results not only furnish new seismological evidence supporting the "two-blocks model" proposed by previous authors, but they also provide additional constraints, useful for better understanding and modeling the seismotectonic processes occurring in the Adriatic region. Numéro de notice : A2023-051 Affiliation des auteurs : non IGN Thématique : POSITIONNEMENT Nature : Article DOI : 10.1016/j.jog.2022.101956 Date de publication en ligne : 30/11/2022 En ligne : https://doi.org/10.1016/j.jog.2022.101956 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102379
in Journal of geodynamics > vol 155 (March 2023) . - n°101956[article]Amazon forest spectral seasonality is consistent across sensor resolutions and driven by leaf demography / Nathan B. Gonçalves in ISPRS Journal of photogrammetry and remote sensing, vol 196 (February 2023)
[article]
Titre : Amazon forest spectral seasonality is consistent across sensor resolutions and driven by leaf demography Type de document : Article/Communication Auteurs : Nathan B. Gonçalves, Auteur ; Ricardo Dalagnol, Auteur ; Jin Wu, Auteur ; et al., Auteur Année de publication : 2023 Article en page(s) : pp 93 - 104 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Amazonie
[Termes IGN] distribution du coefficient de réflexion bidirectionnelle BRDF
[Termes IGN] forêt tropicale
[Termes IGN] image Landsat-8
[Termes IGN] image Landsat-OLI
[Termes IGN] image proche infrarouge
[Termes IGN] image Terra-MODIS
[Termes IGN] indice de végétation
[Termes IGN] Leaf Area Index
[Termes IGN] réflectance spectrale
[Termes IGN] sécheresse
[Termes IGN] variation saisonnièreRésumé : (Auteur) Controversy surrounds the reported dry season greening of the Central Amazon forests based on the Enhanced Vegetation Index (EVI) from the Moderate Resolution Imaging Spectroradiometer (MODIS). As the solar zenith angle decreases during the dry season, it affects the sub-pixel shade content and artificially increases Near-infrared (NIR) reflectance and EVI. MODIS' coarse resolution also creates a challenge for cloud and terrain filtering. To reduce these artifacts and then validate MODIS seasonal spectral patterns we use 16 years of 1 km resolution MODIS-MAIAC (Multi-Angle Implementation of Atmospheric Correction) images, corrected to a nadir view and 45° solar zenith angle, together with an improved cloud filter. Then we show that the 30 m Landsat-8 Operational Land Imager (OLI) surface reflectance over two Landsat scenes provides independent evidence supporting the MODIS-MAIAC seasonality for EVI, NIR, and GCC (an additional important vegetation index, green chromatic coordinate). Our empirical method for controlling for sun-sensor geometry effects in Landsat scenes encompasses the use of seasonally distinct images that have similar solar zenith angles and cloud-free pixels on flat uplands having the same phase angle. We extended this validation to nine Amazon sub-basins comprising ∼546 Landsat-8 images. Our study shows that the dry-season green-up pattern observed by MODIS is corroborated by Landsat-8, and is independent of satellite data artifacts. To investigate the mechanisms driving these seasonal changes we further used Central Amazon tower-mounted RGB cameras providing a 4-year record at the Amazon Tall Tower (ATTO, 2°8′36″S, 59°0′2″W) and a 7-year record at the Manaus k34 tower (2°36′33″ S, 60°12′33″W) to obtain monthly upper canopy green leaf cover (a proxy for Leaf Area Index - LAI) and monthly leaf age class abundances (based on the age since leaf flushing, by crown). These were compared to seasonal patterns of GCC and EVI in small MODIS-MAIAC windows centered on each tower. MODIS-MAIAC GCC was positively correlated with newly flushed leaves (R2 = 0.76 and 0.44 at ATTO and k34, respectively). EVI correlated strongly with the abundance of mature leaves (R2 = 0.82 and 0.80) but was poorly correlated with LAI (R2 = 0.20 and 0.41, respectively). Therefore, seasonal spectral patterns in the Central Amazon are likely controlled by leaf age variation, not quantity of leaf area. Numéro de notice : A2023-065 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2022.12.001 Date de publication en ligne : 04/01/2023 En ligne : https://doi.org/10.1016/j.isprsjprs.2022.12.001 Format de la ressource électronique : URL Article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102423
in ISPRS Journal of photogrammetry and remote sensing > vol 196 (February 2023) . - pp 93 - 104[article]Species-specific deadwood density, its controlling factors and its role in the estimation of deadwood C stock of a Virgin European Beech-Silver Fir Mixed Forest in the Southern Carpathians / Ion Catalin Petritan in SSRN [preprint electronic journal], vol 2023 ([01/02/2023])
[article]
Titre : Species-specific deadwood density, its controlling factors and its role in the estimation of deadwood C stock of a Virgin European Beech-Silver Fir Mixed Forest in the Southern Carpathians Type de document : Article/Communication Auteurs : Ion Catalin Petritan, Auteur Année de publication : 2023 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Abies alba
[Termes IGN] bois mort
[Termes IGN] Carpates
[Termes IGN] décomposition
[Termes IGN] densité du bois
[Termes IGN] estimation statistique
[Termes IGN] Fagus sylvatica
[Termes IGN] peuplement mélangé
[Termes IGN] puits de carbone
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) Deadwood is a fundamental structural and functional component of forests, with a crucial role in supporting the forest biodiversity and nutrient and carbon cycling. Precise deadwood density estimates are necessary to evaluate the biomass and carbon stocked in this component. For a better understanding of the deadwood dynamics in natural forests, given its higher abundance, it is important to achieve deeper knowledge about its decay rate and how it is influenced by environmental factors. In this study, we estimated dry deadwood density for two different tree species, silver fir (Abies alba) and European beech (Fagus sylvatica) and for three snags and five logs decomposition classes (class 1 representing snag/log deadwood at early stages of decomposition and class 3/5 representing snags or logs, respectively, at its most advanced state of decomposition) in a virgin mixed beech-fir forest in the Southern Carpathians. The goal of this study was to assess how deadwood density is influenced by different abiotic (moisture, elevation, slope, aspect) and wood-related factors (rottenness, position of the sampling along the deadwood piece, the contact with the soil).For snags, the mean dry density showed a reduced variability within decomposition classes (484-326 kg.m-3 for beech and 374-319 kg.m-3 for fir), compared to the logs (486-139 kg.m-3 for beech and 359-161 kg.m-3 for fir). While the mass moisture varied slowly in the first three decay classes (around 60-80%), it increased sharply in the last two decay classes of logs (> 140% in the fourth classes and > 350% in the last one). The rottenness increased with the decay degree in a similar way for both species. The contact of logs with the soil influenced positively the moisture of the log, but the position of the sampling along the piece did not play any significant role in the variability of density. The density estimates per decay classes were used to compare the amount of carbon (C) sequestered as deadwood for each species. The mean biomass of C as deadwood at Sinca virgin forest varied greatly among the 21 plots from 0.36 to 41.16 MgC ha-1, with a mean value of 15.96 ± 2.36 (±SE) MgC ha-1.Our study suggests that volume-based calculations might yield biased quantitative estimates of C stored as deadwood unless a local estimate of dead wood density corrected per species and decomposition class is applied. Moreover, using an averaged value of dry density instead of dry density value for each decay class may result in an overestimation of 22% on the estimation of C stock sequestered as deadwood. Thus, our study may also help planning future inventories of C stocks in other virgin forests and for other species, (e.g., make emphasis in estimating densities in all decay classes). Furthermore, it could serve as a methodological basis for more specific research designed to uncover the potential influence of different forest management practices on dry deadwood density. Numéro de notice : A2023-085 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.2139/ssrn.4350235 En ligne : https://dx.doi.org/10.2139/ssrn.4350235 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=102857
in SSRN [preprint electronic journal] > vol 2023 [01/02/2023][article]A machine learning method for Arctic lakes detection in the permafrost areas of Siberia / Piotr Janiec in European journal of remote sensing, vol 56 n° 1 (2023)PermalinkPermalinkPrecipitation frequency in Med-CORDEX and EURO-CORDEX ensembles from 0.44° to convection-permitting resolution: impact of model resolution and convection representation / Minh Ha-Truong in Climate Dynamics, vol 60 n° inconnu (2023)PermalinkClimate and ungulate browsing impair regeneration dynamics in spruce-fir-beech forests in the French Alps / Mithila Unkule in Annals of Forest Science, vol 79 n° 1 (2022)PermalinkClimate envelope analyses suggests significant rearrangements in the distribution ranges of Central European tree species / Gàbor Illés in Annals of Forest Science, vol 79 n° 1 (2022)PermalinkCoastal land use and shoreline evolution along the Nador lagoon Coast in Morocco / Khalid El Khalidi in Geocarto international, vol 37 n° 25 ([01/12/2022])PermalinkForêt amazonienne : de nouveau sous contrôle ? / Laurent Polidori in Géomètre, n° 2208 (décembre 2022)PermalinkIdentification and spatial extent of understory plant species requiring vegetation control to ensure tree regeneration in French forests / Noé Dumas in Annals of Forest Science, vol 79 n° 1 (2022)PermalinkSea surface temperature prediction model for the Black Sea by employing time-series satellite data: a machine learning approach / Hakan Oktay Aydınlı in Applied geomatics, vol 14 n° 4 (December 2022)PermalinkDevelopment and long-term dynamics of old-growth beech-fir forests in the Pyrenees: Evidence from dendroecology and dynamic vegetation modelling / Dario Martín-Benito in Forest ecology and management, vol 524 (November-15 2022)Permalink