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Termes IGN > foresterie > sylviculture > typologie des stations forestières > forêt alpestre
forêt alpestre
Commentaire :
Forêt de montagne, Forêt de moyenne montagne, Forêt des montagnes, Forêt montagnarde, Forêt monticole, Montagne -- Forêt. Typologie des stations forestières. >> Plante alpestre, Forêt subalpine. Source(s) : Formations végétales et paysages ruraux / G. Plaisance, 1959. Consulté en vain : Laval RVM, 1995-08. - LCSH, 1995-03. Domaine(s) : 580. Synonyme(s)forêt de montagneVoir aussi |
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Titre : To die or not to die: Forest dynamics in Switzerland under climate change Type de document : Thèse/HDR Auteurs : Nicolas Bircher, Auteur Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Année de publication : 2015 Collection : Dissertationen ETH num. 22775 Importance : 188 p. Format : 21 x 30 cm Note générale : bibliographie
A thesis submitted to attain the degree of doctor of sciences of ETH ZurichLangues : Anglais (eng) Descripteur : [Termes IGN] composition floristique
[Termes IGN] dynamique de la végétation
[Termes IGN] forêt alpestre
[Termes IGN] inventaire forestier étranger (données)
[Termes IGN] modèle dynamique
[Termes IGN] Picea abies
[Termes IGN] série temporelle
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] Suisse
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) A high diversity of forest ecosystems is found around the globe providing various ecosystem services to humans. Responses of forests to recent increases of drought events have given rise to serious concerns about future forest development. Since anthropogenic climate change is proceeding at an unprecedented rate, the forestry sector is challenged to swiftly develop and plan adaptive management measures that guarantee the sustainable provision of forest ecosystem services in the future. The planning of management strategies is strongly dependent on reliable knowledge on future forest dynamics. To this end, the Swiss government has launched an extensive research program to examine the impact of climate change on Swiss forests. One aim among others is to assess the sensitivity of common forest types of Switzerland to climate change.
Dynamic vegetation models (DVMs) are suitable to provide quantitative assessments of forest sensitivity to climate change, as their flexibility allows considering dynamic vegetation transitions under conditions that do not represent a steady state. Among DVMs, forest gap models portray long-term forest dynamics at the stand scale taking biotic interactions such as competition into account. Recent integration of sophisticated management techniques has substantially extended their range of application from unmanaged to complex mixed-species forests under management, thus making them interesting tools for the assessment of climate change impacts on forest ecosystems. However, forest gap models integrate a large number of ecological processes that still lack an empirical base. This is particularly true for tree mortality – a key demographic process in forest dynamics – where increasing empirical research has been followed by little action in DVMs. Thus, although it is widely acknowledged that empirical functions should be integrated into DVMs to enhance ecological realism, little is known about whet her this approach leads to an increased robustness of model projections.
Given this background, my thesis includes two major objectives: 1) to examine the potential of empirical mortality functions in dynamic vegetation models and 2) to assess the sensitivity of common Swiss forests to climate change.
In Chapter 1 of this thesis, I implemented an inventory- and a tree-ring based mortality function in the forest gap model ForClim and combined them with a stochastic and a deterministic approach for the determination of tree status (alive vs. dead). These four new model versions were tested for two Norway spruces stands, one of which was managed (inventory time series of 72 years) and the other was unmanaged (41 years). Furthermore, I ran long-term simulations (~400 years) into the future to test model behavior under three climate scenarios. I showed that three out of the four mode l versions showed good agreement for stand basal area and stem numbers when compared against inventory data of both forest sites. Due to very similar model behavior, an unambiguous choice of a “best” model version was, however, not possible. In contrast, long -term simulations revealed very different behavior of the mortality models, indicating that the choice of the mortality function is crucial for simulated forest dynamics. Based on these results, I concluded that 1) empirical mortality functions are valuable replacements for current theoretical mortality algorithms in dynamic vegetation models 2) but further tests would be needed to rigorously assess their potential and to better understand interactions of the mortality function with other model processes.
Enhanced use of empirical data in dynamic vegetation models is widely advocated. However, it is largely unknown whether empirically derive d functions are compatible with the wide range of processes and interactions that are usually found in DVMs and thus, whether they lead to an better model performance. In Chapter 2 , I addressed this question with the focus on the inventory-based mortality function that has already been used in Chapter 1 . I used Bayesian methods to recalibrate its mortality parameters within ForClim. I compared its performance with the ForClim version containing the original, empirically fitted mortality parameters and with the current ForClim v3.3 that included a theoretical mortality function. Calibration and subsequent validation was based on inventory data of 30 Swiss natural forest reserves. Similarities between the calibrated and the empirically fitted mortality parameters suggest that the general structure of ForClim is appropriate to integrate empirical mortality functions. However, I found some discrepancies that indicate necessary improvements regarding the role of species’ shade tolerance in growth-mortality relationships and an optimal balance between growth and mortality. Bayesian calibration led to best performance both at calibration and validation sites. Furthermore, it revealed that the sensitivity of ForClim to parametric uncertainty is particularly high for trees in low dbh classes but surprisingly small for standard model outputs such as basal area.
Assessing the sensitivity of common forest stands in Switzerland with a forest gap model makes it necessary 1) to know which forest stands are common and 2) to have suitable data for model initialization. In Chapter 3 , I developed a stratification of the Swiss forest area to identify those forest types of Switzerland that , in terms of their stand structure and tree species composition, are most common in different eco-regions and elevation zones. I used plot data form the third Swiss National Forest Inventory (NFI3) that contained both stand attributes and single-tree data. NFI plots were grouped into eco -regions and elevation zones according to the “Guide for sustainability in protection forests” (NaiS). I further segregated NFI plots into more groups based on two forest stand attributes: vertical stand structure and developmental stage. In a last step, I relied on recommendations of sylvicultural experts for dividing some groups into more strata to strengthen a realistic tree species composition. The stratification resulted in 71 strata that contained 25% of all NFI forest plots. Single-tree data of all NFI plots associated to one stratum were aggregate d. Although the final result is a somewhat “artificial” forest stand, it has the tremendous advantage that NFI plot data can be used directly for stand initialization in the forest gap model ForClim.
In Switzerland, studies on forest sensitivity to climate change often focus on extreme sites where shifts in tree species composition are already visible while less attention is paid to the fate of common forest stands that are most important for Swiss forestry. In Chapter 4, I ran simulations for 71 strata that had been identified in the previous chapter using two model versions to examine their development until the end of the 21 st century (year 2100). Simulations were run with common Swiss forest management strategies and without management. I considered forest development under current climate (1980-2009) and under 11 different climate change scenarios assuming an A2 greenhouse gas emission scenario. According to these simulation results, shifts in structure and composition of Swiss forests have to be expected for the second half of this century. However, high variability among the strata was found due to drivers of small-scaled forest dynamics such as regional climate, elevation gradients and current species composition. I showed that current management regimes can alleviate the negative impacts of climate change but adaptive measures are necessary to be applied at a site-specific and objective-oriented base. In conclusion, model- based assessments on forest sensitivity can only provide reliable decision-making support for forest managers if small-scaled drivers of forest stand dynamics are take n into consideration.
In the Synthesis, I reflect the findings of the previous chapters by discussing the potential of empirical mortality functions in DVMs and the use of forest gap models – as one type of DVM – as tools for decision-support regarding forest management under climate change. I come to the conclusion that empirical mortality functions are capable to further improve the performance of DVMs and to increase our confidence in their projections. However, empirical functions come with limitations, which might constrain avalid applicability. For this reason, I advocate not to focus on one individual function but to aggregate knowledge on mortality mechanism and data from various sources to enhance the validity of the tree mortality mechanism in DVMs beyond individual empirical data sets. Climate change is expected to have strong effects on future development of current Swiss forests at various sites. High variability in forest response to a changing environment underlines the need to plan future forest strategies at the local scale. Forest gap models have limitations that need to be discussed and tackled. Still, I am convinced that they have the potential to play a key role in decision-making processes as they can provide what decision makers need: a comprehensive reflection of essential processes and an adequate spatial resolution.Numéro de notice : 17200 Affiliation des auteurs : non IGN Thématique : FORET Nature : Thèse étrangère Note de thèse : doctoral thesis : Sciences : ETH Zurich : 2015 En ligne : http://dx.doi.org/10.3929/ethz-a-010596194 Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81176 Deadwood and tree microhabitat dynamics in unharvested temperate mountain mixed forests: A life-cycle approach to biodiversity monitoring / Laurent Larrieu in Forest ecology and management, vol 334 ([15/12/2014])
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Titre : Deadwood and tree microhabitat dynamics in unharvested temperate mountain mixed forests: A life-cycle approach to biodiversity monitoring Type de document : Article/Communication Auteurs : Laurent Larrieu, Auteur ; Alain Cabanettes, Auteur ; Pierre Gonin, Auteur ; Thibault Lachat, Auteur ; Yoan Paillet, Auteur ; Stephan Winter, Auteur ; Christophe Bouget, Auteur ; Marc Deconchat, Auteur Année de publication : 2014 Article en page(s) : pp 163 - 173 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] bois mort
[Termes IGN] dynamique de la végétation
[Termes IGN] forêt alpestre
[Termes IGN] forêt tempérée
[Termes IGN] Fraxinus excelsior
[Termes IGN] microhabitat
[Termes IGN] placette d'échantillonnage
[Termes IGN] Prunus avium
[Termes IGN] Sorbus (genre)
[Termes IGN] surveillance écologique
[Termes IGN] xylophage
[Vedettes matières IGN] Ecologie forestièreRésumé : (auteur) In forest ecosystems, conservation is often considered in the absence of any long-term dynamic perspective, yet dynamic processes extend over hundreds of years. Saproxylic taxa represent about 25% of the species diversity in temperate and boreal forests and they depend on both spatial and temporal continuity in the availability of deadwood and certain tree microhabitats. Our study focused on the dynamics of deadwood and tree microhabitats throughout the silvigenetic cycle in 32 unharvested European mountain mixed forests. Our dataset contained 178 plots classified into one of five forest development phases (regeneration, establishing, growing, culmination and disintegration). We analyzed how the amount and quality of deadwood and microhabitats varied according to the five phases. Contrary to expectations, deadwood and tree microhabitat availability remained more or less stable throughout the silvigenetic cycle, both in quantity and diversity. Furthermore, whether the forests were dominated by broadleaves or conifers, there were no significant differences in terms of deadwood or tree microhabitat dynamics. Pioneer (Betula spp., Salix spp.) and post-pioneer species (Fraxinus exelsior, Sorbus spp., Prunus avium) played an important role throughout the silvigenetic cycle by providing a diversity of deadwood when deadwood from the dominant species (i.e. Abies alba, Fagus sylvatica, Picea abies) was scarce. Understanding the dynamics of deadwood and tree microhabitats may help us provide a model for forest managers who intend to emulate natural forest dynamics and will also improve our understanding of the relationship between forest dynamics and biodiversity conservation. Numéro de notice : A2014-597 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Article DOI : 10.1016/j.foreco.2014.09.007 En ligne : http://dx.doi.org/10.1016/j.foreco.2014.09.007 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81010
in Forest ecology and management > vol 334 [15/12/2014] . - pp 163 - 173[article]Large scale road network extraction in forested moutainous areas using airborne laser scanning data / António Ferraz (2014)
Titre : Large scale road network extraction in forested moutainous areas using airborne laser scanning data Type de document : Article/Communication Auteurs : António Ferraz , Auteur ; Clément Mallet , Auteur ; Nesrine Chehata , Auteur Editeur : New York : Institute of Electrical and Electronics Engineers IEEE Année de publication : 2014 Conférence : IGARSS 2014, International Geoscience And Remote Sensing Symposium 13/07/2014 18/07/2014 Québec Québec - Canada Proceedings IEEE Importance : pp 4315 - 4318 Format : 21 x 30 cm Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] apprentissage automatique
[Termes IGN] classification par forêts d'arbres décisionnels
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] extraction du réseau routier
[Termes IGN] forêt alpestre
[Termes IGN] France (administrative)
[Termes IGN] montagne
[Termes IGN] processus ponctuel marqué
[Termes IGN] reconnaissance de formes
[Termes IGN] théorie des graphesRésumé : (auteur) In this work, we present an approach that is able to deal with large-scale road network mapping. While former methods focus on delineating patches of roads without computing a coherent road network, we formulate a very large number of road hypothesis that are pruned using a graph reasoning and weak a priori knowledge on road behavior. The initial solution is computed by means of two machine learning and pattern recognition state-of-the-art methods (namely, Random Forest classification and Marked Point Process) that allow to process very large areas in little time with very satisfactory results. Numéro de notice : C2014-024 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : 10.1109/IGARSS.2014.6947444 Date de publication en ligne : 06/11/2014 En ligne : http://dx.doi.org/10.1109/IGARSS.2014.6947444 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=92029 Documents numériques
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Titre : Forêts anciennes de Méditerranée et des montagnes limitrophes : Références pour la naturalité régionale Type de document : Rapport Auteurs : Magali Rossi, Auteur ; Pierre Bardin, Auteur ; Eugénie Cateau, Auteur ; Daniel Vallauri, Auteur Editeur : Marseille [France] : WWF Année de publication : 2013 Importance : 144 p. Langues : Français (fre) Descripteur : [Termes IGN] échantillonnage
[Termes IGN] espace naturel sensible
[Termes IGN] forêt alpestre
[Termes IGN] forêt ancienne
[Termes IGN] forêt méditerranéenne
[Termes IGN] habitat (nature)
[Termes IGN] microhabitat
[Vedettes matières IGN] Ecologie forestièreMots-clés libres : Naturalité Maturité Haute valeur de conservation Résumé : (auteur) [...] Ce rapport propose une synthèse des résultats d’une étude destinée à caractériser la naturalité des forêts méditerranéennes, menée de 2010 à 2013, dans le cadre du programme Forêts anciennes du WWF France (www.foretsanciennes.fr). Quelle méthode d’analyse de la naturalité est adaptée aux forêts de l’écorégion méditerranéenne ? Celle-ci est-elle fondamentalement différente de celle destinée à d’autres régions, et si oui en quoi ? Est-il possible de développer une méthode d’évaluation qui soit simple,fiable et suffisamment rapide pour être utilisée comme guide par le gestionnaire ? Quelles sont les valeurs de référence des principaux indicateurs de naturalité et d’empreinte écologique humaine dans les hauts lieux de l’écorégion ? En quoi ces valeurs se distinguent-elles des autres forêts ? Cet écart peut-il inspirer une réflexion de gestion ? Autant de questions auxquelles ce rapport tente de répondre. [...] Numéro de notice : 17651 Affiliation des auteurs : non IGN Thématique : FORET Nature : Rapport DOI : sans En ligne : https://www.wwf.fr/sites/default/files/doc-2017-09/13_rapport_forets_anciennes_d [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=97899 Multi-level filtering segmentation to measure individual tree parameters based on Lidar data: Application to a mountainous forest with heterogeneous stands / Cédric Vega in International journal of applied Earth observation and geoinformation, vol 13 n° 4 (August 2011)
[article]
Titre : Multi-level filtering segmentation to measure individual tree parameters based on Lidar data: Application to a mountainous forest with heterogeneous stands Type de document : Article/Communication Auteurs : Cédric Vega , Auteur ; Sylvie Durrieu, Auteur Année de publication : 2011 Projets : TOSCA ExFOLIO / Durrieu, Sylvie Article en page(s) : pp 646 - 656 Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] extraction de la végétation
[Termes IGN] forêt alpestre
[Termes IGN] hauteur des arbres
[Termes IGN] houppier
[Termes IGN] lasergrammétrie
[Termes IGN] modèle numérique de surface de la canopée
[Termes IGN] Pinus nigra
[Termes IGN] troncRésumé : (auteur) This paper presents a method for individual tree crown extraction and characterisation from a canopy surface model (CSM). The method is based on a conventional algorithm used for localising LM on a smoothed version of the CSM and subsequently for modelling the tree crowns around each maximum at the plot level. The novelty of the approach lies in the introduction of controls on both the degree of CSM filtering and the shape of elliptic crowns, in addition to a multi-filtering level crown fusion approach to balance omission and commission errors. The algorithm derives the total tree height and the mean crown diameter from the elliptic tree crowns generated. The method was tested and validated on a mountainous forested area mainly covered by mature and even-aged black pine (Pinus nigra ssp. nigra [Arn.]) stands. Mean stem detection per plot, using this method, was 73.97%. Algorithm performance was affected slightly by both stand density and heterogeneity (i.e. tree diameter classes’ distribution). The total tree height and the mean crown diameter were estimated with root mean squared error values of 1.83 m and 1.48 m respectively. Tree heights were slightly underestimated in flat areas and overestimated on slopes. The average crown diameter was underestimated by 17.46% on average. Numéro de notice : A2011-565 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.jag.2011.04.002 En ligne : https://doi.org/10.1016/j.jag.2011.04.002 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=76409
in International journal of applied Earth observation and geoinformation > vol 13 n° 4 (August 2011) . - pp 646 - 656[article]Impact de l’anthropisation ancienne sur la biodiversité d’un habitat de hêtraie-sapinière montagnarde / Laurent Larrieu in Revue forestière française, vol 61 n° 4 (juillet - août 2009)PermalinkPotential productivity of forested areas based on a biophysical model. A case study of a mountainous region in northern Spain / Raquel Benavides in Annals of Forest Science, Vol 66 n° 1 (January - February 2009)PermalinkEstimation de l’influence de la couverture forestière sur les pluies en montagne : exemple du massif de la Chartreuse / Dominique Dumas in Revue forestière française, vol 60 n° 6 (novembre - décembre 2008)PermalinkApproche phytosanitaire de l’impact des blocs rocheux sur le tronc des arbres en forêts de montagne / Alain Soutrenon in Revue forestière française, vol 60 n° 4 (juillet - août 2008)PermalinkConduite de peuplements mélangés en forêts de montagne : exemple d'une collaboration chercheurs-gestionnaires / Xavier Gauquelin in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkLes interactions entre espèces d'arbres dans les mélanges illustrées par le cas des feuillus et des conifères dans les forêts de montagne / Richard Michalet in Revue forestière française, vol 60 n° 2 (mars - avril 2008)PermalinkNotice de la carte de la végétation du parc national du Mercantour au 1:100 000 : répartition des séries dynamiques de la végétation dans le contexte biogéographique des Alpes-maritimes et de la Haute-Provence / Marcel Barbero in Ecologia mediterranea, vol 29 n° 2 (2003)Permalinkn° 210 - 2002-3 - Forest assessment and monitoring (Bulletin de Unasylva)Permalinkn° 195 - 1998-4 - Soulever des montagnes (Bulletin de Unasylva)PermalinkDe la forêt de montagne ... aux forêts en montagne / Christian Barthod in Cahiers du Département de la santé des forêts, vol 1996 n° 5 (septembre 1996)Permalink