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PASSIFOR, Propositions d'Amélioration du Système de Suivi de la biodiversité Forestière [rapport final] / Guy Landmann (2015)
Titre : PASSIFOR, Propositions d'Amélioration du Système de Suivi de la biodiversité Forestière [rapport final] : Convention E30/2012 entre le Ministère de l'agriculture, de l'agroalimentaire et de la forêt et le GIP Ecofor Type de document : Rapport Auteurs : Guy Landmann, Éditeur scientifique ; Frédéric Gosselin, Éditeur scientifique Editeur : Paris : Ministère de l'agriculture, de l'agroalimentaire et de la forêt MAAF Année de publication : 2015 Autre Editeur : Paris [France] : GIP Ecofor Importance : 101 p. Format : 21 x 30 cm Note générale : bibliographie Langues : Français (fre) Descripteur : [Termes IGN] biodiversité
[Termes IGN] biodiversité végétale
[Termes IGN] Coleoptera (ordre)
[Termes IGN] peuplement forestier
[Termes IGN] protection de la biodiversité
[Termes IGN] surveillance écologique
[Vedettes matières IGN] Ecologie forestièreRésumé : (éditeur) Le travail entrepris dans le cadre du projet PASSIFOR (Tâche 1) vise à une identification, un état des lieux et une analyse des réseaux de suivi forestier et/ou de biodiversité en France. Nous avons ciblé des réseaux montrant une composante forestière majoritaire, à l’échelle nationale ou subnationale, avec une couverture taxonomique correspondant à la communauté ou la population, et possédant un protocole et un plan d’échantillonnage renseignés. Le rapport du projet PASSIFOR comporte de 3 volets : Volet 1. État des lieux des réseaux de suivi de la biodiversité et inventaires forestiers existants en France. Volet 2. Test méthodologique comparant les diversités des coléoptères saproxyliques par identification morphologique et métabarcoding. Volet 3. Elaboration d’un projet de recherche appliquée et d’expertise sur des maquettes de suivi de la biodiversité forestière : PASSIFOR-2. Note de contenu : 1. Etat des lieux des réseaux de suivi de la biodiversité et inventaires forestiers existants en France
2. Test méthodologique comparant les diversités des coléoptères saproxyliques par identification morphologique et métabarcoding
3. Élaboration d'un projet de recherche appliquée et d’expertise sur des maquettes de suivi de la biodiversité forestière : PASSIFOR-2Numéro de notice : 19809 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Rapport de mission En ligne : http://www.gip-ecofor.org/doc/drupal/PASSIFOR_VF3.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85252 The Forests in Germany / Federal ministry of food and agriculture = Bundesministerium für Ernährung und Landwirtschaft (Berlin, Allemagne) (2015)
Titre : The Forests in Germany : selected results of the third national forest inventory Type de document : Rapport Auteurs : Federal ministry of food and agriculture = Bundesministerium für Ernährung und Landwirtschaft (Berlin, Allemagne), Auteur ; Christian Schmidt, Préfacier, etc. Editeur : Berlin : Federal ministry of food and agriculture BMEL Année de publication : 2015 Importance : 54 p. Format : 21 x 30 cm Note générale : Glossaire Langues : Anglais (eng) Descripteur : [Termes IGN] Allemagne
[Termes IGN] biotope
[Termes IGN] changement climatique
[Termes IGN] espèce exotique envahissante
[Termes IGN] Fagus (genre)
[Termes IGN] forêt
[Termes IGN] habitat forestier
[Termes IGN] Picea abies
[Termes IGN] Pinus (genre)
[Termes IGN] Quercus (genre)
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] surveillance forestière
[Vedettes matières IGN] Ecologie forestièreRésumé : (Editeur) [Introduction] The forest possesses many talents. It is a home for animals and plants, an important climate protector and contains a wealth of biological diversity. For us, it is also an important supplier of raw materials. We need timber to build houses and furniture, for the production of energy and for the paper on which this booklet is printed. The forest is, however, also a place of peace and quiet that offers us refuge and recreation in our hectic, fast-paced world. Therefore, the forest is indispensable for all of our lives. One third of Germany is forested over 11.4 million hectares. The Third National Forest Inventory (NFI) provides good news: Our forest area has remained unchanged. More timber is re-growing than we use. We also have more of it than any other country in the European Union. In spite of high use, our forest stocks rose to 3.7 billion cubic metres. The appearance of German forests is characterized by 90 billion old and young spruces, pines, beeches, oaks and other tree species. The percentage of deciduous trees has risen. The forests have become more diverse and natural in structure. We find more deadwood in them – an important foundation for biodiversity. The good condition of our forests is the consequence of the silvicultural actions of many forest owners and foresters and the result of a forestry policy based on balance and sustainability that distributes the responsibilities on many shoulders: roughly half of German forests are privately owned. One fifth of them are owned by municipalities, cities and other public entities. One third belong to the Länder and the Federal government. But the National Forest Inventory also indicates the need for action. One example is the spruce: the NFI confirms that the spruce – an important supplier of raw material for the timber industry – is in decline. We must therefore talk about how much spruce forest we need and what alternatives there are to the spruce in the face of climate change. The forest should be used in the best possible way without overtaxing it. To make sure of this, the Federal government devised the Forest Strategy 2020. Its objective is to express and harmonize our diverse demands on the forest. This is the only way to maintain our chances for having intact forests for future generations as well. That is why my maxim is “Our forests: utilize and preserve.” The aim of this booklet is to generate understanding for the forest, forest owners and foresters. It provides citizens with the opportunity to get to know the functions of the forest and appreciate its value. Hence, the booklet is a contribution to sustainable forest management. Note de contenu : 1. Germany, the land of forests – forest area unchanged
- The forests – mainly privately owned
- Varying forest abundance in the Länder
2. The forest habitat – more biological diversity in the forest
- Spruce, pine, beech, oak – the most common tree species
- Forest damage led to rethinking – climate change faces us with new challenges
- Increase in older forests
- Rise in numbers of deciduous trees
- Forests more diversely structured
- Naturalness of tree species composition is somewhat improved
- More deadwood found than ten years ago
- Specially protected biotopes on five percent of the forest area
- Invasive plants in the forest are currently of little significance
- Biotope trees – stepping stones for biological diversity
- Conservation status of large-area forest habitat types protected under the Fauna-Flora-Habitats Directive
3. The forest resources – timber stock at record high
- Stock rose again
- Rise in stock primarily among large-girth trees
- The special case of spruce – stock decreased
- Timber increment at a high level
- Timber use at a high level
- Growth greater than use
- Timber use increasingly restricted or suspended
4. The forests as climate protectors – still a carbon sink
5. Surveying the forest
- Open during inventory – the inventory procedure
- National Forest Inventory – established information basisNuméro de notice : 22453 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Rapport Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=79981 Documents numériques
en open access
22453-Forests_in_Germany-BWI.pdfAdobe Acrobat PDF
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 Towards an enhanced understanding of airborne LiDAR measurements of forest vegetation / Aarne Hovi (2015)
Titre : Towards an enhanced understanding of airborne LiDAR measurements of forest vegetation Type de document : Thèse/HDR Auteurs : Aarne Hovi, Auteur Editeur : Vantaa [Finlande] : Finnish Society of Forest Science Année de publication : 2015 Collection : Dissertationes forestales, ISSN 1795-7389 num. 200 Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-651-489-8 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] analyse de sensibilité
[Termes IGN] composition d'un peuplement forestier
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] espèce végétale
[Termes IGN] forme d'onde
[Termes IGN] identification automatique
[Termes IGN] photogrammétrie terrestre
[Termes IGN] signal laserRésumé : (auteur) This thesis presents basic research on how airborne LiDAR measurements of forest vegetation are influenced by the interplay of the geometric-optical properties of vegetation, sensor function and acquisition settings. Within the work, examining the potential of waveform (WF) recording sensors was of particular interest.
Study I focused upon discrete return LiDAR measurements of understory trees. It showed that transmission losses influenced the intensity of observations and echo triggering probabilities, and also skewed the distribution of echoes towards those triggered by highly reflective or dense targets. The intensity data were of low value for species identification, but the abundance of understory trees could be predicted based on echo height distributions.
In study II, a method of close-range terrestrial photogrammetry was developed. Images were shown as being useful for visualizations and even the geometric quality control of LiDAR data. The strength of backscattering was shown to correlate with the projected area extracted from the images.
In study III, a LiDAR simulation model was developed and validated against real measurements. The model was able to be used for sensitivity analyses to illustrate how plant structure or different pulse properties influence the WF data. Both simulated and real data showed that WF data were able to capture small-scale variations in the structural and optical properties of juvenile forest vegetation.
Study IV illustrated the potential of WF data in the species classification of larger trees. The WF features that separated tree species were also dependent on other variables such as tree size and phenology. Inherent between-tree differences in structure were quantified and the effects of pulse density on the features were examined.
Overall, the thesis provides basic findings on how LiDAR pulses interact with forest vegetation, and serves to link theory with real observations. The results contribute to an improved understanding of LiDAR measurements and their limitations, and thus provide support for further improvements in both data interpretation methods and specific sensor design.Numéro de notice : 14979 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Thèse étrangère Note de thèse : PhD : Forest sciences : University of Helsinki : 2015 En ligne : http://www.metla.fi/dissertationes/df200.htm Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78367 Tropical forest structure characterization using airborne lidar data: an individual tree level approach / António Ferraz (dec 2015)
Titre : Tropical forest structure characterization using airborne lidar data: an individual tree level approach Type de document : Article/Communication Auteurs : António Ferraz , Auteur ; Sassan Saatchi, Auteur ; Clément Mallet , Auteur ; Victoria Meyer, Auteur Editeur : Washington DC [Maryland - Etats-Unis] : American Geophysical Union AGU Année de publication : dec 2015 Conférence : AGU 2015 Fall Meeting 14/10/2015 18/12/2015 San Francisco Californie - Etats-Unis Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] arbre (flore)
[Termes IGN] biomasse aérienne
[Termes IGN] distribution spatiale
[Termes IGN] données lidar
[Termes IGN] données localisées 3D
[Termes IGN] forêt tropicale
[Termes IGN] hauteur des arbres
[Termes IGN] houppier
[Termes IGN] Panama
[Termes IGN] segmentation
[Termes IGN] semis de points
[Termes IGN] structure d'un peuplement forestierRésumé : (auteur) Fine scale tropical forest structure characterization has been performed by means of field measurements techniques that record both the specie and the diameter at the breast height (dbh) for every tree within a given area. Due to dense and complex vegetation, additional important ecological variables (e.g. the tree height and crown size) are usually not measured because they are hardly recognized from the ground. The poor knowledge on the 3D tropical forest structure has been a major limitation for the understanding of different ecological issues such as the spatial distribution of carbon stocks, regeneration and competition dynamics and light penetration gradient assessments. Airborne laser scanning (ALS) is an active remote sensing technique that provides georeferenced distance measurements between the aircraft and the surface. It provides an unstructured 3D point cloud that is a high-resolution model of the forest. This study presents the first approach for tropical forest characterization at a fine scale using remote sensing data. The multi-modal lidar point cloud is decomposed into 3D clusters that correspond to single trees by means of a technique called Adaptive Mean Shift Segmentation (AMS3D). The ability of the corresponding individual tree metrics (tree height, crown area and crown volume) for the estimation of above ground biomass (agb) over the 50 ha CTFS plot in Barro Colorado Island is here assessed. We conclude that our approach is able to map the agb spatial distribution with an error of nearly 12% (RMSE=28 Mg ha-1) compared with field-based estimates over 1ha plots. Numéro de notice : C2015-033 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : FORET/IMAGERIE Nature : Communication nature-HAL : ComAvecCL&ActesPubliésIntl DOI : sans En ligne : https://agu.confex.com/agu/fm15/meetingapp.cgi/Paper/75802 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83298 Post-fire selective thinning of Arbutus unedo L. coppices keeps animal diversity unchanged: the case of ants / Lidia Quevedo in Annals of Forest Science, vol 71 n° 8 (December 2014)PermalinkEconomics of harvesting uneven-aged forest stands in Fennoscandia / Janne Rämo in Scandinavian journal of forest research, vol 29 n° 8 (October 2014)PermalinkQuantification et cartographie de la structure forestière à partir de la texture des images Pléiades / Benoit Beguet in Revue Française de Photogrammétrie et de Télédétection, n° 208 (Octobre 2014)PermalinkSocial status-mediated tree-ring responses to climate of Abies alba and Fagus sylvatica shift in importance with increasing stand basal area / François Lebourgeois in Forest ecology and management, Vol 328 (September 2014)PermalinkComparison of airborne laser scanning methods for estimating forest structure indicators based on Lorenz curves / Rubén Valbuena in ISPRS Journal of photogrammetry and remote sensing, vol 95 (September 2014)PermalinkAssessing tree dendrometrics in young regenerating plantations using terrestrial laser scanning / Ying Li in Annals of Forest Science, vol 71 n° 4 (June 2014)PermalinkManaging coppice forests for rockfall protection: lessons from modeling / Anna Radkte in Annals of Forest Science, vol 71 n° 4 (June 2014)PermalinkStand structure and plant species occurrence in forest edge habitat along different aged roads on Okinawa Island, southwestern Japan / Tsutomu Enoki in Journal of Forest Research, vol 19 n° 1 (February 2014)PermalinkCaractérisation et cartographie de la structure forestière à partir d'images satellitaires à très haute résolution spatiale / Benoit Beguet (2014)PermalinkLa forêt en chiffres et en cartes / Institut national de l'information géographique et forestière (2012 -) (2014)Permalink