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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 Economics of harvesting uneven-aged forest stands in Fennoscandia / Janne Rämo in Scandinavian journal of forest research, vol 29 n° 8 (October 2014)
[article]
Titre : Economics of harvesting uneven-aged forest stands in Fennoscandia Type de document : Article/Communication Auteurs : Janne Rämo, Auteur ; Olli Tahvonen, Auteur Année de publication : 2014 Article en page(s) : pp 777 - 792 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Economie
[Termes IGN] Betula (genre)
[Termes IGN] Fennoscandie
[Termes IGN] forêt inéquienne
[Termes IGN] peuplement forestier
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] rendementRésumé : (auteur) This study analyzes the optimal harvesting of uneven-aged Norway spruce (Picea abies (L.) Karst.), Scots pine (Pinus sylvestris L.), and birch (Betula pendula Roth. and B. pubescens Ehrh.) stands. The analysis is based on an economic description of uneven-aged forestry using a size-structured transition matrix model and a single-tree model. The optimization problem is solved in its general dynamic form using gradient-based interior point methods. Increasing the harvesting interval decreases the annual volume yield. Assuming natural regeneration, this suggests that volume yield is maximized by uneven-aged rather than even-aged management. The present value of stumpage revenues is maximized after saw timber and pulpwood prices, interest rate, and a 15-year harvesting interval are included. The economically optimal solution with a 3% interest rate produces an annual yield of 1.9, 6.2, and 3.1 cubic meters for Scots pine, Norway spruce, and birch, respectively. Both the optimal volume yield and net present value maximization solutions converge to unique species- and site-type-specific steady states with constant harvests. The transition matrix model typically used in optimization studies is computationally less demanding than the single-tree model, but the differences in optimal solutions are more remarkable than earlier studies suggest. Numéro de notice : A2014-783 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1080/02827581.2014.982166 Date de publication en ligne : 31/10/2014 En ligne : http://dx.doi.org/10.1080/02827581.2014.982166 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79380
in Scandinavian journal of forest research > vol 29 n° 8 (October 2014) . - pp 777 - 792[article]Spatial patterns of historical growth changes in Norway spruce across western European mountains and the key effect of climate warming / Marie Charru in Trees, vol 28 n° 1 (February 2014)
[article]
Titre : Spatial patterns of historical growth changes in Norway spruce across western European mountains and the key effect of climate warming Type de document : Article/Communication Auteurs : Marie Charru, Auteur ; Ingrid Seynave, Auteur ; Jean-Christophe Hervé (1961-2017) , Auteur ; Jean-Daniel Bontemps , Auteur Année de publication : 2014 Article en page(s) : pp 205 - 221 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] Alpes (France)
[Termes IGN] analyse diachronique
[Termes IGN] changement climatique
[Termes IGN] croissance des arbres
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] Jura, massif du
[Termes IGN] Massif central (France)
[Termes IGN] Picea abies
[Termes IGN] régression géographiquement pondérée
[Termes IGN] surface terrière
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) While forest growth changes have been observed in many places worldwide, their spatial variation and environmental origin remain poorly documented. Analysis of these historical changes in contrasted regional contexts, and their mapping over continuous environmental gradients, may help uncover their environmental causes. The approach was tested on Norway spruce (Picea abies) in three western European mountain contexts (Massif Central, Alps and Jura), using National Forest Inventory (NFI) data. We explored the environmental factors influencing stand basal area increment (BAI) in each context. We then estimated and compared mean regional changes in BAI and related these to the regional environmental limitations evidenced. Within each region, we further mapped local BAI trends using a geographically weighted regression (GWR) approach. In each region, local estimates of BAI changes were finally correlated to environmental indicators. We found an increase in BAI in the three regions over 1980–2005, greater in the Massif Central (+71 %) than in the Alps (+19 %) and the Jura Mountains (+21 %). Inter-regional differences in BAI changes suggested the release of a thermal constraint—found more important in the Massif Central—by the strong temperature increase over the period, and a limitation by water availability in the Jura and the Alps Mountains. Spatial patterns of BAI change revealed significant local variations in the Massif Central and the Alps. From the correlation analysis, these were again found consistent with the hypothesis of an enhancing effect of climate warming in these mountain ranges. They were also related to local soil nutritional status in the two regions, and negatively related to nitrogen deposition level in the Massif Central. As a main outcome, a strong context and spatial scale dependence of productivity changes is emphasized. In addition, the enhancing effect of climate warming on productivity is suggested, with local modulation by climatic and nutritional conditions. Numéro de notice : A2014-801 Affiliation des auteurs : LIF+Ext (2012-2019) Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1007/s00468-013-0943-4 Date de publication en ligne : 23/10/2013 En ligne : http://dx.doi.org/10.1007/s00468-013-0943-4 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83814
in Trees > vol 28 n° 1 (February 2014) . - pp 205 - 221[article]La forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2014)
Titre : La forêt en chiffres et en cartes : Le mémento [résultats issus des campagnes d’inventaire 2009 à 2013] Type de document : Rapport Auteurs : Institut national de l'information géographique et forestière (2012 -), Auteur Mention d'édition : édition 2014 Editeur : Saint-Mandé : Institut national de l'information géographique et forestière - IGN (2012-) Année de publication : 2014 Langues : Français (fre) Descripteur : [Termes IGN] arbre caducifolié
[Termes IGN] bois mort
[Termes IGN] Carpinus betulus
[Termes IGN] Castanea (genre)
[Termes IGN] données statistiques
[Termes IGN] Fagus (genre)
[Termes IGN] forêt
[Termes IGN] France métropolitaine
[Termes IGN] Fraxinus (genre)
[Termes IGN] grande région écologique
[Termes IGN] inventaire forestier national (données France)
[Termes IGN] peuplement forestier
[Termes IGN] Picea abies
[Termes IGN] Pinophyta
[Termes IGN] Pinus (genre)
[Termes IGN] Quercus (genre)
[Vedettes matières IGN] Inventaire forestierNote de contenu : La forêt en France métropolitaine
L'évolution de la surface forestière
Le taux de boisement par département et par sylvoécorégion
À qui la forêt appartient-elle ?
La composition des peuplements.
La diversité des peuplements
Le bois vivant sur pied
La production biologique annuelle
Les prélèvements de bois
Les peupleraies
Le bois mort sur pied
Le bois mort au sol
Les chênes
Le hêtre - Le charme
Le frêne - Le châtaignier
Le pin maritime - Le pin sylvestre
L'épicéa commun - Le sapin pectiné
Les pins laricio et noir - Le douglas
Quelques données régionalesNuméro de notice : 15828 Affiliation des auteurs : IGN (2012-2019) Thématique : FORET Nature : Rapport statistique nature-HAL : Rapport DOI : sans En ligne : http://www.ign.fr/publications-de-l-ign/Institut/Publications/Autres_publication [...] Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=75074 Voir aussi
- La forêt française / Inventaire forestier national (1958 - 2011) (2010)
- La forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2012)
- La forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2013)
- La forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2016)
- Résultats d'inventaire forestier : méthodologie pour bien comprendre les résultats publiés 2011- 2015 / Institut national de l'information géographique et forestière (2012 -) (2016)
- Le mémento inventaire forestier, édition 2017 / Institut national de l'information géographique et forestière (2012 -) (2017)
- La forêt française : état des lieux et évolutions récentes / M. Garnier (2018)
Documents numériques
en open access
La forêt en chiffres et en cartes, ed. 2014Adobe Acrobat PDF Single tree biomass modelling using airborne laser scanning / Ville Kankare in ISPRS Journal of photogrammetry and remote sensing, vol 85 (November 2013)
[article]
Titre : Single tree biomass modelling using airborne laser scanning Type de document : Article/Communication Auteurs : Ville Kankare, Auteur ; Minna Räty, Auteur ; Xiaowei Yu, Auteur ; et al., Auteur Année de publication : 2013 Article en page(s) : pp 66 - 73 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] biomasse (combustible)
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] estimation statistique
[Termes IGN] extraction automatique
[Termes IGN] Picea abies
[Termes IGN] Pinus sylvestris
[Termes IGN] semis de points
[Termes IGN] troncRésumé : (Auteur) Accurate forest biomass mapping methods would provide the means for e.g. detecting bioenergy potential, biofuel and forest-bound carbon. The demand for practical biomass mapping methods at all forest levels is growing worldwide, and viable options are being developed. Airborne laser scanning (ALS) is a promising forest biomass mapping technique, due to its capability of measuring the three-dimensional forest vegetation structure. The objective of the study was to develop new methods for tree-level biomass estimation using metrics derived from ALS point clouds and to compare the results with field references collected using destructive sampling and with existing biomass models. The study area was located in Evo, southern Finland. ALS data was collected in 2009 with pulse density equalling approximately 10 pulses/m2. Linear models were developed for the following tree biomass components: total, stem wood, living branch and total canopy biomass. ALS-derived geometric and statistical point metrics were used as explanatory variables when creating the models. The total and stem biomass root mean square error per cents equalled 26.3% and 28.4% for Scots pine (Pinus sylvestris L.), and 36.8% and 27.6% for Norway spruce (Picea abies (L.) H. Karst.), respectively. The results showed that higher estimation accuracy for all biomass components can be achieved with models created in this study compared to existing allometric biomass models when ALS-derived height and diameter were used as input parameters. Best results were achieved when adding field-measured diameter and height as inputs in the existing biomass models. The only exceptions to this were the canopy and living branch biomass estimations for spruce. The achieved results are encouraging for the use of ALS-derived metrics in biomass mapping and for further development of the models. Numéro de notice : A2013-607 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2013.08.008 En ligne : https://doi.org/10.1016/j.isprsjprs.2013.08.008 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=32743
in ISPRS Journal of photogrammetry and remote sensing > vol 85 (November 2013) . - pp 66 - 73[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 081-2013111 RAB Revue Centre de documentation En réserve L003 Disponible Le statut social d’un arbre influence-t-il sa réponse au climat ? Étude dendroécologique sur le Sapin, l’Epicéa, le Pin sylvestre, le Hêtre et le Chêne sessile / Pierre Mérian in Revue forestière française, vol 65 n°1 (janvier - février 2013)PermalinkLa forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2013)PermalinkOak (Quercus robur L.) regeneration as a response to natural dynamics of stands in European hemiboreal zone / Andrzej Bobiec in European Journal of Forest Research, vol 130 n° 5 (September 2011)PermalinkInterCETEF 2009 en Auvergne : diagnostiquer les risques, pour mieux les prévenir / Alain Colinot in Forêt entreprise, n° 191 (mars 2010/2)PermalinkLutte engagée contre le dendroctone de l'épicéa / Abdel Moutaoukil in Le Bois International : l'officiel du bois [édition verte], vol 2010 n° 3 (23 janvier 2010)PermalinkEffet de la variabilité climatique et des événements extrêmes sur la croissance d’Abies alba, Picea abies et Pinus sylvestris en climat tempéré français / François Lebourgeois in Revue forestière française, vol 62 n° 1 (janvier - février 2010)PermalinkImpact potentiel du changement climatique sur la distribution de l’Épicéa, du Sapin, du Hêtre et du Chêne sessile en France / Christian Piedallu in Revue forestière française, vol 61 n° 6 (novembre - décembre 2009)PermalinkDes résineux dépérissent en Midi-Pyrénées ! / Jean-Pierre Ortisset in Forêt entreprise, n° 188 (2009/5)PermalinkL'épicéa commun / Isabelle Flouret in Forêts de France, n° 523 (mai 2009)PermalinkLa forêt face aux tempêtes / Yves Birot (2009)PermalinkEvaluation of the visual stress grading standard on French Spruce (Picea excelsa) and Douglas-fir (Pseudotsuga menziesii) sawn timber / Guillaume Roblot in Annals of Forest Science, Vol 65 n° 8 (December 2008)PermalinkUltrasonic tomography of green wood using a non-parametric imaging algorithm with reflected waves / Loïc Brancheriau in Annals of Forest Science, Vol 65 n° 7 (October - November 2008)PermalinkLe typographe / Louis-Michel Nageleisen in Forêts de France, n° 515 (juillet - août 2008)PermalinkVente d'épicéas sans grande surprise dans les Ardennes / Anne-Benoîte Valiergue in Le Bois International : l'officiel du bois [édition verte], vol 2008 n° 16 (26 avril 2008)PermalinkSpecies identification of individual trees by combining high resolution LiDAR data with multi-spectral images / Johan Holmgren in International Journal of Remote Sensing IJRS, vol 29 n° 5 (March 2008)PermalinkModel-based prediction error uncertainty estimation for K-NN method / H.J. Kim in Remote sensing of environment, vol 104 n° 3 (15/10/2006)PermalinkDernières nouvelles des géants de lorraine et d'alsace / Gérard Colin in Revue forestière française, vol 50 n° 5 (1998)PermalinkSensor band selection for detecting current defoliation caused by the spruce budworm / D.G. Leckie in Remote sensing of environment, vol 26 n° 1 (01/10/1988)PermalinkContribution à la cartographie forestière en zone fortement morcelée à l'aide de l'imagerie SPOT / N. Aboussouan (23/11/1987)PermalinkLes forêts naturelles d'épicéas et de pins de montagne du Jura / Jean-Louis Richard in Bulletin de la Société Neuchâteloise des Sciences Naturelles, n° 89 (1966)Permalink