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1. Estimation of forest height and above ground biomass from ICESat/GLAS data in Eucalyptus plantations in Brazil

Author

Rodrigo Hakamada, Jean-Stéphane Bailly, Cristiane Lemos, Ibrahim Fayad, Guerric Le Maire, Nicolas Baghdadi, Yann Nouvellon, Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro), International Paper do Brasil, Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), and Institut de Recherche pour le Développement (IRD)-Institut de Recherche pour le Développement (IRD [ Madagascar])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)

Subjects
Estimation, Canopy, Biomass (ecology), Measurement, 010504 meteorology & atmospheric sciences, Lasers, 0211 other engineering and technologies, Biological system modeling, Data models, [SDU.STU]Sciences of the Universe [physics]/Earth Sciences, Terrain, 02 engineering and technology, 15. Life on land, 01 natural sciences, Eucalyptus, Laser radar, Lidar, Environmental science, Altimeter, Biomass, Digital elevation model, 021101 geological & geomatics engineering, 0105 earth and related environmental sciences, Remote sensing
Abstract

International audience; The Geoscience Laser Altimeter System (GLAS) has provided a useful dataset for estimating forest height in many areas of the globe. Most of the studies on GLAS waveforms have focused on natural forests and only a few were conducted over forest plantations. The objective of this study was to test the best known models used for estimating canopy height and above ground biomass of intensively managed Eucalyptus plantations in Brazil using full waveform LiDAR data. Studies to estimate forest heights from LiDAR data have highlighted that the fitting coefficients of developed models are strongly dependent on environmental factors such as the region of the study site, terrain topography, and forest type. In this study, we evaluated the main models developed to predict canopy height using a combination of parameters extracted from GLAS waveforms and a digital elevation model, in order to explore which combination of parameters yields the best forest height estimates. In addition, a model to estimate above ground biomass from dominant height was calibrated.

Published
2014

2. Testing Different Methods of Forest Height and Aboveground Biomass Estimations From ICESat/GLAS Data in Eucalyptus Plantations in Brazil

Author

Ibrahim Fayad, Guerric Le Maire, Yann Nouvellon, Nicolas Baghdadi, Cristiane Lemos, Jean-Stéphane Bailly, Rodrigo Hakamada, Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Ecologie fonctionnelle et biogéochimie des sols et des agro-écosystèmes (UMR Eco&Sols), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Territoires, Environnement, Télédétection et Information Spatiale (UMR TETIS), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-AgroParisTech-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA), Laboratoire d'étude des Interactions Sol - Agrosystème - Hydrosystème (UMR LISAH), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), AgroParisTech, International Paper do Brasil, Institut National de la Recherche Agronomique (INRA)-Institut de Recherche pour le Développement (IRD)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut de Recherche pour le Développement (IRD [ Madagascar])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA), and Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)

Subjects
Eucalyptus grandis, Atmospheric Science, Télédétection, Natural forest, Laser, EUCALIPTO, Biomasse, Altimeter, Computers in Earth Sciences, Croissance, Digital elevation model, Hauteur, Remote sensing, Biomass (ecology), ICESat/ GLAS, Méthode statistique, [SDE.IE]Environmental Sciences/Environmental Engineering, Inventaire forestier, Aboveground biomass, Forestry, Vegetation, 15. Life on land, Plantation forestière, Eucalyptus, K10 - Production forestière, forest height, Environmental science, U30 - Méthodes de recherche, Modèle mathématique, planted Eucalyptus forest
Abstract

[Departement_IRSTEA]Territoires [TR1_IRSTEA]SYNERGIE [Axe_IRSTEA]TETIS-ATTOS; International audience; The Geoscience Laser Altimeter System (GLAS) has provided a useful dataset for estimating forest heights in many areas of the globe. Most of the studies on GLAS waveforms have fo- cused on natural forests and only a few were conducted over forest plantations. This work set out to estimate the stand-scale dominant height and aboveground biomass of intensively managed Euca- lyptus plantations in Brazil using the most commonly used models developed for natural forests. These forest plantations are valuable case studies, with large and numerous stands that are very uni- form, in which field measurements are precise compared to nat- ural forests. The height of planted Eucalyptus forest stands esti- mated from waveforms acquired by GLAS were compared with in situ measurements in order to determine the model that produced the best forest height estimates. For our slightly sloping study site (slope < 7°), the direct method defined as the difference between the signal begin and the ground peak provided forest height es- timates with an accuracy of 2.2 m. The use of statistical models based on waveform metrics and digital elevation models provided slightly better results (1.89 m accuracy) in comparison with the di- rect method and the most relevant metrics proved to be the trailing edge extent and the waveform extent. Moreover, a power law model was used to fit in situ aboveground biomass to in situ forest height. The results using this model with GLAS-derived heights showed an accuracy for biomass of 16.1 Mg/ha.

Published
2014

3. Classification and mapping of anthropogenic landforms on cultivated hillslopes using DEMs and soil thickness data - Example from the SW Parisian Basin, France

Author

Sébastien Salvador-Blanes, Florent Hinschberger, Jean-Jacques Macaire, Hocine Bourennane, Caroline Chartin, Transferts continentaux : forçages anthropiques, climatiques et géodynamiques, Institut des Sciences de la Terre d'Orléans (ISTO), Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Université de Tours-Centre National de la Recherche Scientifique (CNRS), Unité de Science du Sol, Institut National de la Recherche Agronomique (INRA), Université de Tours (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université de Tours (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Financial support provided by the ANR (Agence Nationale de la Recherche) VMCS project LANDSOIL is gratefully acknowledged. The authors would like to thank Jean-Paul Bakyono and Isabel Pene-Galland for data collection in the field. This paper was much improved thanks to the comments of Peter Houben and an anonymous referee and thanks to Lauren Valverde who revised my english style., and Chartin, Caroline

Subjects
010504 meteorology & atmospheric sciences, Soil test, Morphometric attributes, [SDE.MCG]Environmental Sciences/Global Changes, Digital Elevation Model, Structural basin, bassin parisien, Spatial distribution, 01 natural sciences, Field borders, Lynchet, Digital elevation model, [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces, environment, Geomorphology, 0105 earth and related environmental sciences, Earth-Surface Processes, geography, geography.geographical_feature_category, Landform, anthropogenic landform, predictive modelling, parisian basin, modèle numérique de terrain, attribut morphométrique, épaisseur du sol, banquette, parcellaire, arbre de classification, digital elevation model, morphometric attribute, soil thickness, lynchet, field border, classification tree, relief anthropique, modélisation prédictive, physical, geosciences, multidisciplinary, geology, 04 agricultural and veterinary sciences, 15. Life on land, Current (stream), 040103 agronomy & agriculture, 0401 agriculture, forestry, and fisheries, Spatial variability, Classification Tree, Geology, Soil thickness
Abstract

International audience; This study focuses on linear anthropogenic landforms of decametric width on cultivated hillslopes and their relations to soil thickness variability. The 16 ha study area shows a rolling topography supported by Cretaceous chalk of the SW Parisian Basin, France. Two types of landforms were identified: lynchets, similar to those described as soil terraces occurring on downslope field parts in other contexts, and undulations, linear, convex landforms that cut across fields. Accurate DEM construction and a detailed soil thickness survey were performed all over the study area. Soil samples were classified considering their location on specific types of anthropogenic landforms. The classification tree (CT) method was applied to assess whether lynchets and undulations can be discriminated through morphometric attributes (slope, curvature, profile curvature and planform curvature) and soil thickness (CTsoil) or through morphometric attributes only (CTtopo). The CT application establishes predictive classification models to map the spatial distribution of lynchets and undulations over the whole study area. The validation results of the CTsoil and CTtopo applications show model efficiencies of 83% and 67%, respectively. Both models performed well for lynchets. Errors arise mainly from difficulties in unequivocally discriminating gently convex undulations and undifferentiated surfaces, especially when soil thickness is not accounted for. Mean values of soil thickness are 1.08, 0.62 and 0.45 m in lynchets, undulations and undifferentiated areas, respectively. The general shape of the thickened soil is characteristic to each type of anthropogenic landform. Multi-temporal mapping of field border networks shows that undulations are linked to borders that were removed during the latest land consolidation. Lynchets are associated with current field borders. Lynchets and undulations, which cover 39% of the study area, define topographic indicators of human-induced soil accumulations. The method involves perspectives for efficiently mapping and quantifying the anthropogenically modified spatial variability of soil thickness on agricultural hillsides.

Published
2011