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The crown condition of Norway spruce and occurrence of symptoms caused by Armillaria spp. in mixed stands / Petr Čermák in Journal of forest science, vol 66 n° 12 (December 2020)
[article]
Titre : The crown condition of Norway spruce and occurrence of symptoms caused by Armillaria spp. in mixed stands Type de document : Article/Communication Auteurs : Petr Čermák, Auteur ; Zid Tomáš, Auteur Année de publication : 2020 Article en page(s) : pp 483 – 491 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] abattage (sylviculture)
[Termes IGN] défoliation
[Termes IGN] feuillu
[Termes IGN] Fungi
[Termes IGN] peuplement mélangé
[Termes IGN] Picea abies
[Termes IGN] République Tchèque
[Termes IGN] sécheresse
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Mixed stands are currently supported as effective management options to reduce forest vulnerability to climate change. However, our issues about benefits of mixtures, mechanisms of their incidence and conditions for their effectiveness have yet been only partly clarified. We assessed the crown condition of Norway spruce (Picea abies /L./ Karst) and occurrence of symptoms caused by Armillaria spp. on spruce in a small area in the Drahanská vrchovina Highlands (Czech Republic) in differently mixed stands in 2002 and 2019. We found that although the broadleaf abundance affected the total defoliation of Norway spruce, the effect was unstable in time. The observed effect of altitudinal zones and Norway spruce abundance on the occurrence of symptoms of Armillaria root rot in spruce was also unstable. The drought during recent four years and the implemented forestry measures (salvage and intermediate felling) can be reasons for the relationship instability. We did not identify any statistically significant relationship between tree species diversity (Simpson’s Index) and defoliation. Numéro de notice : A2020-802 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.17221/86/2020-JFS En ligne : https://doi.org/10.17221/86/2020-JFS Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96757
in Journal of forest science > vol 66 n° 12 (December 2020) . - pp 483 – 491[article]Drought stress detection in juvenile oilseed rape using hyperspectral imaging with a focus on spectra variability / Wiktor R. Żelazny in Remote sensing, vol 12 n° 20 (October-2 2020)
[article]
Titre : Drought stress detection in juvenile oilseed rape using hyperspectral imaging with a focus on spectra variability Type de document : Article/Communication Auteurs : Wiktor R. Żelazny, Auteur ; Jan Lukáš, Auteur Année de publication : 2020 Article en page(s) : 27 p. Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] Brassica napus subsp. napus
[Termes IGN] classification par séparateurs à vaste marge
[Termes IGN] classification pixellaire
[Termes IGN] image hyperspectrale
[Termes IGN] indice de végétation
[Termes IGN] modèle linéaire
[Termes IGN] Normalized Difference Vegetation Index
[Termes IGN] sécheresse
[Termes IGN] segmentation d'image
[Termes IGN] stress hydriqueRésumé : (auteur) Hyperspectral imaging (HSI) has been gaining recognition as a promising proximal and remote sensing technique for crop drought stress detection. A modelling approach accounting for the treatment effects on the stress indicators’ standard deviations was applied to proximal images of oilseed rape—a crop subjected to various HSI studies, with the exception of drought. The aim of the present study was to determine the spectral responses of two cultivars, `Cadeli` and `Viking’, representing distinctive water management strategies, to three types of watering regimes. Hyperspectral data cubes were acquired at the leaf level using a 2D frame camera. The influence of the experimental factors on the extent of leaf discolorations, vegetation index values, and principal component scores was investigated using Bayesian linear models. Clear treatment effects were obtained primarily for the vegetation indexes with respect to the watering regimes. The mean values of RGI, MTCI, RNDVI, and GI responded to the difference between the well-watered and water-deprived plants. The RGI index excelled among them in terms of effect strengths, which amounted to −0.96[−2.21,0.21] and −0.71[−1.97,0.49] units for each cultivar. A consistent increase in the multiple index standard deviations, especially RGI, PSRI, TCARI, and TCARI/OSAVI, was associated with worsening of the hydric regime. These increases were captured not only for the dry treatment but also for the plants subjected to regeneration after a drought episode, particularly by PSRI (a multiplicative effect of 0.33[0.16,0.68] for `Cadeli’). This result suggests a higher sensitivity of the vegetation index variability measures relative to the means in the context of the oilseed rape drought stress diagnosis and justifies the application of HSI to capture these effects. RGI is an index deserving additional scrutiny in future studies, as both its mean and standard deviation were affected by the watering regimes. Numéro de notice : A2020-656 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.3390/rs12203462 Date de publication en ligne : 21/10/2020 En ligne : https://doi.org/10.3390/rs12203462 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96123
in Remote sensing > vol 12 n° 20 (October-2 2020) . - 27 p.[article]Global Climate [in “State of the Climate in 2019"] / A. Ades in Bulletin of the American Meteorological Society, vol 101 n° 8 (August 2020)
[article]
Titre : Global Climate [in “State of the Climate in 2019"] Type de document : Article/Communication Auteurs : A. Ades, Auteur ; R. Adler, Auteur ; et al., Auteur ; Olivier Bock , Auteur Année de publication : 2020 Projets : 1-Pas de projet / Article en page(s) : pp S9 - S128 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Atmosphère
[Termes IGN] changement climatique
[Termes IGN] circulation atmosphérique
[Termes IGN] climat terrestre
[Termes IGN] cryosphère
[Termes IGN] données météorologiques
[Termes IGN] gaz à effet de serre
[Termes IGN] humidité de l'air
[Termes IGN] humidité du sol
[Termes IGN] précipitation
[Termes IGN] sécheresse
[Termes IGN] température de l'airRésumé : (auteur) [introduction] The assessments and analyses presented in this chapter focus predominantly on the measured differences of climate and weather observables from previous conditions, years, and decades to place 2019 in context. Many of these differences have direct impacts on people, for example, their health and environment, as well as the wider biosphere, but are beyond the scope of these analyses. For the last few State of the Climate reports, an update on the number of warmer-than-average years has held no surprises, and this year is again no different. The year 2019 was among the three warmest years since records began in the mid-to-late 1800s. Only 2016, and for some datasets 2015, were warmer than 2019; all years after 2013 have been warmer than all others back to the mid-1800s. Each decade since 1980 has been successively warmer than the preceding decade, with the most recent (2010–19) being around 0.2°C warmer than the previous (2000–09). This warming of the land and ocean surface is reflected across the globe. For example, lake and permafrost temperatures have increased; glaciers have continued to lose mass, becoming thinner for the 32nd consecutive year, with the majority also becoming shorter during 2019. The period during which Northern Hemisphere (NH) lakes were covered in ice was seven days shorter than the 1981–2010 long-term average, based on in situ phenological records. There were fewer cool extremes and more warm extremes on land; regions including Europe, Japan, Pakistan, and India all experienced heat waves. More strong than moderate marine heat waves were recorded for the sixth consecutive year. And in Australia (discussed in more detail in section 7h4), moisture deficits and prolonged high temperatures led to severe impacts during late austral spring and summer, including devastating wildfires. Smoke from these wildfires was detected across large parts of the Southern Hemisphere (SH). [...] Numéro de notice : A2020-798 Affiliation des auteurs : UMR IPGP-Géod+Ext (2020- ) Thématique : POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1175/BAMS-D-20-0104.1 Date de publication en ligne : 12/08/2020 En ligne : https://doi.org/10.1175/BAMS-D-20-0104.1 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96582
in Bulletin of the American Meteorological Society > vol 101 n° 8 (August 2020) . - pp S9 - S128[article]The impact of drought on total ozone flux in a mountain Norway spruce forest / Thomas Agyei in Journal of forest science, vol 66 n° 7 (juillet 2020)
[article]
Titre : The impact of drought on total ozone flux in a mountain Norway spruce forest Type de document : Article/Communication Auteurs : Thomas Agyei, Auteur ; Stanislav Juráň, Auteur ; Kojo Kwakye Ofori-Amanfo, Auteur ; et al., Auteur Année de publication : 2020 Article en page(s) : pp 280 - 287 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] covariance
[Termes IGN] dioxyde de carbone
[Termes IGN] écosystème forestier
[Termes IGN] forêt alpestre
[Termes IGN] ozone
[Termes IGN] photosynthèse
[Termes IGN] Picea abies
[Termes IGN] République Tchèque
[Termes IGN] sécheresse
[Termes IGN] teneur en vapeur d'eau
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) In order to understand the impact of summer drought on dry deposition of tropospheric ozone (O3), we compared severe and mild drought periods of summer 2018 in a mountain Norway spruce forest at Bílý Kříž, Beskydy Mts. An eddy covariance technique was applied to measure diurnal courses of the ecosystem O3 and CO2 fluxes. Low O3 deposition was recorded in the morning and evening, while the highest CO2 and O3 fluxes were recorded during the central hours of the day. Total O3 deposition during severe drought (soil humidity 13%) was significantly higher than the deposition during the mild drought period (soil humidity 19%). Our data indicate that high vapour pressure deficit and low soil humidity during severe drought led to the stomatal closure, while non-stomatal O3 deposition, associated with chemical reactions of O3 with NO and volatile organic compounds, are responsible for higher total O3 deposition during the severe drought period. Therefore, we assume that under severe drought stomatal O3 uptake decreases but non-stomatal depositions to forest ecosystems substantially increase. Numéro de notice : A2020-628 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.17221/129/2019-JFS En ligne : https://doi.org/10.17221/129/2019-JFS Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=96032
in Journal of forest science > vol 66 n° 7 (juillet 2020) . - pp 280 - 287[article]Decreasing stand density favors resistance, resilience, and recovery of Quercus petraea trees to a severe drought, particularly on dry sites / Anna Schmitt in Annals of Forest Science, Vol 77 n° 2 (June 2020)
[article]
Titre : Decreasing stand density favors resistance, resilience, and recovery of Quercus petraea trees to a severe drought, particularly on dry sites Type de document : Article/Communication Auteurs : Anna Schmitt, Auteur ; Raphaël Trouvé, Auteur ; Ingrid Seynave, Auteur ; François Lebourgeois, Auteur Année de publication : 2020 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] bilan hydrique
[Termes IGN] densité de la végétation
[Termes IGN] peuplement forestier
[Termes IGN] Quercus sessiliflora
[Termes IGN] résilience écologique
[Termes IGN] sécheresse
[Termes IGN] sylviculture
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Key message: Decreasing stand density increases resistance, resilience, and recovery of Quercus petraea trees to severe drought (2003), particularly on dry sites, and the effect was independent of tree social status. Context: Controlling competition is an advocated strategy to modulate the response of trees to predicted changes in climate. Aims: We investigated the effects of stand density (low, medium, high; relative density index 0.20, 0.53, 1.04), social status (dominant, codominant, suppressed), and water balance (dry, mesic, wet; summer water balance − 182, − 126, − 96 mm) on the climate-growth relationships (1997–2012) and resistance (Rt), resilience (Rs), and recovery (Rc) following the 2003 drought. Methods: Basal area increments were collected by coring (269 trees) in young stands (28 ± 7.5 years in 2012) of sessile oak (Quercus petraea) in a French permanent network of silvicultural plots. Results: We showed that the climate-growth relationships depend on average site-level water balance with trees highly dependent on spring and summer droughts on dry and mesic sites and not at all on wet sites. Neither stand density nor social status modulated mean response to climate. Decreasing stand density increased Rt, Rs, and Rc particularly on dry sites. The effect was independent of tree social position within the stand. Conclusion: Reducing stand density mitigates more the effect of extreme drought events on drier sites than on wet sites. Numéro de notice : A2020-292 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s13595-020-00959-9 Date de publication en ligne : 26/05/2020 En ligne : https://doi.org/10.1007/s13595-020-00959-9 Format de la ressource électronique : url article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=95122
in Annals of Forest Science > Vol 77 n° 2 (June 2020)[article]Year-to-year crown condition poorly contributes to ring width variations of beech trees in French ICP level I network / Clara Tallieu in Forest ecology and management, Vol 465 (1st June 2020)PermalinkClinal variation along precipitation gradients in Patagonian temperate forests: unravelling demographic and selection signatures in three Nothofagus spp. / Carolina Soliani in Annals of Forest Science, Vol 77 n° 1 (March 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, Vol 77 n° 1 (March 2020)PermalinkThe effects of different combinations of simulated climate change-related stressors on juveniles of seven forest tree species grown as mono-species and mixed cultures / Alfas Pliüra in Baltic forestry, vol 26 n° 1 ([01/02/2020])PermalinkEtudes des dynamiques spatiales d’évolution de l’occupation et de l’utilisation des sols dans la fenêtre lacustre camerounaise du lac Tchad et son arrière-pays à partir des grandes sécheresses sahéliennes de 1970 / Paul Gérard Gbetkom (2020)PermalinkVulnerability of forest ecosystems to fire in the French Alps / Sylvain Dupire in European Journal of Forest Research, Vol 138 n° 5 (octobre 2019)PermalinkMultitemporal Landsat-MODIS fusion for cropland drought monitoring in El Salvador / Nguyen-Thanh Son in Geocarto international, vol 34 n° 12 ([15/09/2019])PermalinkMonitoring of extreme land hydrology events in central Poland using GRACE, land surface models and absolute gravity data / Joanna Kuczynska-Siehien in Journal of applied geodesy, vol 13 n° 3 (July 2019)PermalinkInterpreting 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)PermalinkThinning around old oaks in spruce production forests: current practices show no positive effect on oak growth rates and need fine tuning / Igor Drobyshev in Scandinavian journal of forest research, vol 34 n° 2 (March 2019)Permalink