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Developing allometric equations for estimating shrub biomass in a Boreal Fen / Annie He in Forests, vol 9 n° 9 (September 2018)  

Public [article]  inForests > vol 9 n° 9 (September 2018) Titre : Developing allometric equations for estimating shrub biomass in a Boreal Fen Type de document : Article/Communication Auteurs : Annie He, Auteur ; Gregory J. McDermid, Auteur ; Mir Mustafizur Rahman, Auteur ; Maria Strack, Auteur ; Saraswati Saraswati, Auteur ; Bin Xu, Auteur Année de publication : 2018 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation [Termes IGN] allométrie [Termes IGN] Alnus (genre) [Termes IGN] biomasse aérienne [Termes IGN] estimation statistique [Termes IGN] marais [Termes IGN] Salix (genre) [Termes IGN] tourbe Résumé : (Auteur) Allometric equations for estimating aboveground biomass (AGB) from easily measured plant attributes are unavailable for most species common to mid-continental boreal peatlands, where shrubs comprise a large component of the vegetation community. Our study develops allometric equations for three dominant genera found in boreal fens: Alnus spp. (alder), Salix spp. (willow) and Betula pumila (bog birch). Two different types of local equations were developed: (1) individual equations based on genus/phylogeny, and (2) a general equation that pooled all individuals regardless of genera. The general equation had a R2 = 0.97 (n = 82), and was not significantly different (p > 0.05) than any of the phylogenetic equations. This indicated that a single generalized equation is sufficient in estimating AGB for all three genera occurring in our study area. A closer look at the performance of the general equation revealed that smaller stems were predicted less accurately than larger stems because of the higher variability of leafy biomass found in small individuals. Previously published equations developed in other ecoregions did not perform as well as our local equations. Numéro de notice : A2018-502 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.3390/f9090569 Date de publication en ligne : 15/09/2018 En ligne : https://doi.org/10.3390/f9090569 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=91216 [article]

A disturbance inventory framework for flexible and reliable landscape monitoring / J. Linke in Photogrammetric Engineering & Remote Sensing, PERS, vol 75 n° 8 (August 2009)  

Public [article]  inPhotogrammetric Engineering & Remote Sensing, PERS > vol 75 n° 8 (August 2009) . - pp 981 - 995 Titre : A disturbance inventory framework for flexible and reliable landscape monitoring Type de document : Article/Communication Auteurs : J. Linke, Auteur ; Gregory J. McDermid, Auteur ; D. Laskin, Auteur ; et al., Auteur Année de publication : 2009 Article en page(s) : pp 981 - 995 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Traitement d'image optique [Termes IGN] Alberta (Canada) [Termes IGN] analyse de données [Termes IGN] base de données d'occupation du sol [Termes IGN] carte d'occupation du sol [Termes IGN] détection de changement [Termes IGN] forêt [Termes IGN] image Landsat [Termes IGN] image multitemporelle [Termes IGN] occupation du sol [Termes IGN] surveillance Résumé : (Auteur) Remote sensing plays a key role in landscape monitoring, but our handling of these data in a multi-temporal time series is not yet fully developed. Of particular concern is the presence of spatial and thematic errors in independently created maps that distort measures of landscape pattern and constrain the reliability of change analysis. In addition, there is a need to incorporate continuous attributes of cover gradients for flexible map representations that support a variety of applications. In this paper, we present a framework for generating temporally and categorically dynamic land-cover maps that provide such a reliable and adaptable foundation. The centerpiece is a spatio-temporal disturbance-inventory database, created through semi-automated change detection and conditioned with boundary-matching procedures, which can be used to backdate and update both continuous and categorical reference maps. We demonstrate our approach using multi-annual Landsat imagery from a forested region in west-central Alberta, Canada, between the years 1998 and 2005. Copyright ASPRS Numéro de notice : A2009-310 Affiliation des auteurs : non IGN Thématique : FORET/IMAGERIE Nature : Article DOI : 10.14358/PERS.75.8.981 En ligne : https://doi.org/10.14358/PERS.75.8.981 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=29940 [article]