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Contingent valuation and choice experiment of citizens’ willingness to pay for forest conservation in southern Finland / Emmi Haltia (2015)  

Public Titre : Contingent valuation and choice experiment of citizens’ willingness to pay for forest conservation in southern Finland Type de document : Thèse/HDR Auteurs : Emmi Haltia, Auteur Editeur : University of Eastern Finland Année de publication : 2015 Collection : Dissertationes forestales, ISSN 1795-7389 Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-651-497-3 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation [Termes IGN] analyse de sensibilité [Termes IGN] économie verte [Termes IGN] habitat forestier [Termes IGN] protection de l'environnement [Termes IGN] protection de la biodiversité [Termes IGN] service écosystémique Mots-clés libres : évaluation contingente Résumé : (auteur) Environmental quality has a direct effect on citizens’ welfare. To quantify this effect, the four articles of this thesis analyse Finnish citizens’ willingness to pay (WTP) for increased forest conservation using the contingent valuation (CV) and choice experiment (CE) methods. These methods are based on neo-classical welfare economics augmented with the choice process framework originating from psychology and behavioural economics. Using the CV method, we analyse how WTP is affected by respondents’ uncertainty, by the share of nonrespondents and by the considerably high share of “yes” responses at the highest proposed costs to households. The CE data are used to study the effects of different conservation programme characteristics on WTP. The results show that Finnish citizens support increased forest conservation. The median WTP in the contingent valuation was 72 EUR, i.e. 50% of respondents supported increased conservation if the costs per household did not exceed 72 EUR. The mean WTP estimates were sensitive to modelling assumptions and assumptions concerning the nonrespondent preferences. This emphasises the need for careful sensitivity analyses when results are used for welfare measurement and policy planning. Respondents’ choices in the valuation questions were affected by the household costs of conservation and other socioeconomic characteristics. The results suggest that the choices in valuation tasks are affected by economic and psychological factors. The study gives important insights into the choice behaviour and lower and upper bound estimates of WTP. These estimates are somewhat lower than those in comparable earlier Finnish studies. In CV, respondents seemed insensitive to programme size while the extent of the proposed project had a significant effect on the choices in CE. Numéro de notice : 14977 Affiliation des auteurs : non IGN Thématique : BIODIVERSITE/FORET Nature : Thèse étrangère Note de thèse : PhD : Forest sciences : University of Helsinki : 2015 En ligne : https://dissertationesforestales.fi/pdf/article1987.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78365

Forest structure indicators based on tree size inequality and their relationships to airborne laser scanning / Rubén Valbuena (2015)  

Public Titre : Forest structure indicators based on tree size inequality and their relationships to airborne laser scanning Type de document : Thèse/HDR Auteurs : Rubén Valbuena, Auteur Editeur : Vantaa [Finlande] : Finnish Society of Forest Science Année de publication : 2015 Collection : Dissertationes forestales, ISSN 1795-7389 num. 205 Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-651-499-7 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie [Termes IGN] composition d'un peuplement forestier [Termes IGN] courbe de Lorenz [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] entropie [Termes IGN] hauteur des arbres Résumé : (auteur) The subject of this doctoral thesis is the non-spatial indices of horizontal differentiation that can be used as indicators of forest structural complexity, specifically as descriptors of tree size inequality. The body of the thesis focuses primarily on the indicators themselves, while the appended articles tackle issues mainly related to their practical estimation using airborne laser scanning (ALS) remote sensing. The overall research is framed in the context of developing a system of indicators that can be applied at pan-European level, whose implementation in practice is foreseen in the advent of national ALS surveying programmes. A list of indicators available in the scientific literature for describing forest structural heterogeneity by means of horizontal differentiation was tested. Indices based on the theory of information demonstrated critical inconsistencies, which rendered them inadequate for describing tree size inequality. This was revealed using the theory on intrinsic ordering, and illustrated with diversity and equitability profiles. The use of Shannon, and similar indices based on generalized entropy, to describe diversity between size classes, which has been common practice, is therefore discouraged. The link between majorization and Lorenz ordering was established for the specific case of tree size distributions, discussing the reliability of analysing the Lorenz curve to fully describe size inequality in tree populations. In forest science, the Lorenz curve relates stem frequency distributions to their corresponding basal area-weighted distributions. Indicators based on the Lorenz curve, such as the Gini coefficient (GC), were therefore chosen for their ALS-based estimation. Adding an indicator describing Lorenz curve’s asymmetry was deemed necessary for describing relative understorey development. Research demonstrated the convenience of using the basal area larger than the mean (BALM), as it defined the position of the Lorenz curve inflexion point, which depicts the quadratic mean diameter (QMD). It was observed that, when using Lorenz curves to describe forest structure, the position of the QMD should be compared with the Lorenz curve of a theoretical uniform DBH distribution, which represents maximum entropy. Accordingly, this thesis includes a discussion of how Lorenz ordering can be used as a method, providing a scale for simultaneously comparing relative dispersion and entropy. In conclusion, the final recommended indicators are GC and BALM, since this bivariate description of forest structure fully characterises the relationships of relative dominance among trees in a forest population. The most similar neighbour (MSN) imputation of tree lists is defended as a substantially convenient method for predicting these indicators by ALS. Numéro de notice : 14976 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Thèse étrangère Note de thèse : PhD : Forest Sciences : University of Eastern Finland : 2015 En ligne : http://www.metla.fi/dissertationes/df205.htm Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78363

Towards an enhanced understanding of airborne LiDAR measurements of forest vegetation / Aarne Hovi (2015)  

Public 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 laser Résumé : (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

Use of remotely sensed auxiliary data for improving sample-based forest inventories / Svetlana Saarela (2015)  

Public Titre : Use of remotely sensed auxiliary data for improving sample-based forest inventories Type de document : Thèse/HDR Auteurs : Svetlana Saarela, Auteur Editeur : Vantaa [Finlande] : Finnish Society of Forest Science Année de publication : 2015 Collection : Dissertationes forestales, ISSN 1795-7389 num. 201 Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-6514911-8 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] analyse multivariée [Termes IGN] données auxiliaires [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] échantillonnage de données [Termes IGN] Finlande [Termes IGN] forêt boréale [Termes IGN] image Landsat [Termes IGN] inférence statistique [Termes IGN] inventaire forestier étranger (données) [Termes IGN] placette d'échantillonnage [Termes IGN] tronc [Vedettes matières IGN] Inventaire forestier Résumé : (auteur) Over the past decades it has been shown that remotely sensed auxiliary data have a potential to increase the precision of key estimators in sample-based forest surveys. This thesis was motivated by the increasing availability of remotely sensed data, and the objectives were to investigate how this type of auxiliary data can be used for improving both the design and the estimators in sample-based surveys. Two different modes of inference were studied: model-based inference and design-based inference. Empirical data for the studies were acquired from a boreal forest area in the Kuortane region of western Finland. The data comprised a combination of auxiliary information derived from airborne LiDAR and Landsat data, and field sample plot data collected using a modification of the 10th Finnish National Forest Inventory. The studied forest attribute was growing stock volume. The results of this thesis are important for the development of forest inventories to meet the requirements which stem from an increasing number of international commitments and agreements related to forests. Numéro de notice : 14978 Affiliation des auteurs : non IGN Thématique : FORET Nature : Thèse étrangère Note de thèse : PhD : Forest sciences : University of Helsinki : 2015 En ligne : Over the past decades it has been shown that remotely sensed auxiliary data have [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=78366

Assesment of manual and automated methods for updating stand-level forest inventories based on aerial photography / Perttu Antilla (2005)

Public Titre : Assesment of manual and automated methods for updating stand-level forest inventories based on aerial photography Type de document : Thèse/HDR Auteurs : Perttu Antilla, Auteur ; Risto Päivinen, Directeur de thèse ; Matti Maltamo, Directeur de thèse Editeur : Vantaa [Finlande] : Finnish Society of Forest Science Année de publication : 2005 Collection : Dissertationes forestales, ISSN 1795-7389 num. 9 Importance : 42 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-951-651-108-8 Note générale : bibliographie Academic Dissertation, Faculty of Forestry, University of Joensuu, Finland Langues : Anglais (eng) Descripteur : [Termes IGN] actualité des données [Termes IGN] appariement d'images [Termes IGN] détection d'arbres [Termes IGN] détection de changement [Termes IGN] Finlande [Termes IGN] forêt boréale [Termes IGN] identification automatique [Termes IGN] inventaire forestier (techniques et méthodes) [Termes IGN] inventaire forestier étranger (données) [Termes IGN] peuplement forestier [Termes IGN] photo-identification [Termes IGN] photogrammétrie aérienne [Vedettes matières IGN] Inventaire forestier Résumé : (auteur) Data collection for forest planning in private forestry in Finland is based on periodic, labour-intensive, stand level field inventories. Therefore, to increase guidance for forest owners more cost-efficient methods that replace or supplement field inventories are needed so as to reallocate labour resources. In addition, for active forest owners, up-to-date information is of interest. The aim of this thesis was to test the applicability of different inventory and updating methods that are based on aerial photography for the regional forest inventory of private forests in Finland. Four approaches were chosen: I) stand level visual interpretation of changes and simulation of stand development, 2) automatic, stand level interpretation of aerial photographs utilising nonparametric estimation, 3) automatic, photogrammetric estimation of mean height, and 4) automatic, monoscopic identification of individual trees. Approaches I and 2 are inventory or updating methods, while approaches 3 and 4 can be considered as components of such methods. Approach 1 was found to be appropriate for operative use for estates that have not ordered a forest plan, provided that the strict prerequisites for the inventory area are met. The- accuracy of approach 2, as such, was not considered to be high enough for forest planning, but this very inexpensive method could turn out to be applicable, if its accuracy could be improved. Approach 3 was based on image matching and would be most useful as a part of other methods, like template matching in multiple images. Although only identification of trees was tested in approach 4, the applicability of whole single tree based inventory method was appraised. Relatively high costs and low accuracy limit the possibilities to use this method, in practice. Note de contenu : Introduction 1 - Material 2 - Methods 3 - Results 4 - Discussion Numéro de notice : 21692 Affiliation des auteurs : non IGN Thématique : FORET Nature : Thèse étrangère Note de thèse : Academic Dissertation : Forestry : University of Joensuu : 2005 Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=90928