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Transferability and calibration of airborne laser scanning based mixed-effects models to estimate the attributes of sawlog-sized Scots pines / Lauri Korhonen in Silva fennica, vol 53 n° 3 (2019)  

Public [article]  inSilva fennica > vol 53 n° 3 (2019) Titre : Transferability and calibration of airborne laser scanning based mixed-effects models to estimate the attributes of sawlog-sized Scots pines Type de document : Article/Communication Auteurs : Lauri Korhonen, Auteur ; Jaakko Repola, Auteur ; Tomi Karjalainen, Auteur ; Petteri Packalen, Auteur ; Matti Maltamo, Auteur Année de publication : 2019 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] détection d'arbres [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] erreur systématique [Termes IGN] estimation statistique [Termes IGN] étalonnage de modèle [Termes IGN] hauteur à la base du houppier [Termes IGN] houppier [Termes IGN] inventaire forestier (techniques et méthodes) [Termes IGN] lasergrammétrie [Termes IGN] Pinus sylvestris [Termes IGN] placette d'échantillonnage [Vedettes matières IGN] Inventaire forestier Résumé : (auteur) Airborne laser scanning (ALS) data is nowadays often available for forest inventory purposes, but adequate field data for constructing new forest attribute models for each area may be lacking. Thus there is a need to study the transferability of existing ALS-based models among different inventory areas. The objective of our study was to apply ALS-based mixed models to estimate the diameter, height and crown base height of individual sawlog sized Scots pines (Pinus sylvestrisL.) at three different inventory sites in eastern Finland. Different ALS sensors and acquisition parameters were used at each site. Multivariate mixed-effects models were fitted at one site and the models were validated at two independent test sites. Validation was carried out by applying the fixed parts of the mixed models as such, and by calibrating them using 1–3 sample trees per plot. The results showed that the relative RMSEs of the predictions were 1.2–6.5 percent points larger at the test sites compared to the training site. Systematic errors of 2.4–6.2 percent points also emerged at the test sites. However, both the RMSEs and the systematic errors decreased with calibration. The results showed that mixed-effects models of individual tree attributes can be successfully transferred and calibrated to other ALS inventory areas in a level of accuracy that appears suitable for practical applications. Numéro de notice : A2019-641 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14214/sf.10179 Date de publication en ligne : 31/07/2019 En ligne : https://doi.org/10.14214/sf.10179 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=93446 [article]

Incorporating tree- and stand-level information on crown base height into multivariate forest management inventories based on airborne laser scanning / Matti Maltamo in Silva fennica, vol 52 n° 3 ([01/08/2018])  

Public [article]  inSilva fennica > vol 52 n° 3 [01/08/2018] Titre : Incorporating tree- and stand-level information on crown base height into multivariate forest management inventories based on airborne laser scanning Type de document : Article/Communication Auteurs : Matti Maltamo, Auteur ; Tomi Karjalainen, Auteur ; Jaakko Repola, Auteur ; Jari Vauhkonen, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] classification barycentrique [Termes IGN] données lidar [Termes IGN] données localisées 3D [Termes IGN] hauteur à la base du houppier [Termes IGN] hauteur des arbres [Termes IGN] houppier [Termes IGN] inventaire forestier (techniques et méthodes) [Termes IGN] modèle de simulation [Termes IGN] Pinus (genre) [Termes IGN] placette d'échantillonnage [Termes IGN] régression [Vedettes matières IGN] Inventaire forestier Résumé : (Auteur) This study examines the alternatives to include crown base height (CBH) predictions in operational forest inventories based on airborne laser scanning (ALS) data. We studied 265 field sample plots in a strongly pine-dominated area in northeastern Finland. The CBH prediction alternatives used area-based metrics of sparse ALS data to produce this attribute by means of: 1) Tree-level imputation based on the k-nearest neighbor (k-nn) method and full field-measured tree lists including CBH observations as reference data; 2) Tree-level mixed-effects model (LME) prediction based on tree diameter (DBH) and height and ALS metrics as predictors of the models; 3) Plot-level prediction based on analyzing the computational geometry and topology of the ALS point clouds; and 4) Plot-level regression analysis using average CBH observations of the plots for model fitting. The results showed that all of the methods predicted CBH with an accuracy of 1–1.5 m. The plot-level regression model was the most accurate alternative, although alternatives producing tree-level information may be more interesting for inventories aiming at forest management planning. For this purpose, k-nn approach is promising and it only requires that field measurements of CBH is added to the tree lists used as reference data. Alternatively, the LME-approach produced good results especially in the case of dominant trees. Numéro de notice : A2018-509 Affiliation des auteurs : non IGN Thématique : FORET/MATHEMATIQUE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.14214/sf.10006 Date de publication en ligne : 27/07/2018 En ligne : https://doi.org/10.14214/sf.10006 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91190 [article]

Causes and consequences of accelarating tree growth in Europe / Tomi Karjalainen (1999)    

Public Titre : Causes and consequences of accelarating tree growth in Europe : Proceedings of the International Seminar held in Nancy, France 14-16 May 1998 Type de document : Actes de congrès Auteurs : Tomi Karjalainen, Éditeur scientifique ; Olivier Laroussinie, Éditeur scientifique ; Heinrich Spiecker, Éditeur scientifique Editeur : Joensuu [Finlande] : European forest institute EFI Année de publication : 1999 Collection : Proceedings, ISSN 1237-8801 num. 27 Importance : 285 p. ISBN/ISSN/EAN : 978-952-9844-53-1 Langues : Anglais (eng) Descripteur : [Termes IGN] Europe (géographie politique) Index. décimale : 422.2 Politique forestière - Europe & international Numéro de notice : IFN_1403 Affiliation des auteurs : non IGN Thématique : FORET Nature : Actes En ligne : https://efi.int/publications-bank/causes-and-consequences-accelerating-tree-grow [...] Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=66414

Exemplaires(1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
IFN-001-001216	422.2 KAR	Livre	Nogent-sur-Vernisson	Bibliothèque Nogent IFN	Exclu du prêt

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