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Pit-mound microrelief in forest soils: Review of implications for water retention and hydrologic modelling / Martin Valtera in Forest ecology and management, vol 393 (1 June 2017)
[article]
Titre : Pit-mound microrelief in forest soils: Review of implications for water retention and hydrologic modelling Type de document : Article/Communication Auteurs : Martin Valtera, Auteur ; Randall J. Schaetzl, Auteur Année de publication : 2017 Article en page(s) : pp 40 - 51 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] écosystème forestier
[Termes IGN] gestion forestière durable
[Termes IGN] microtopographie
[Termes IGN] ruissellement
[Termes IGN] santé des forêts
[Termes IGN] sol forestier
[Termes IGN] stress hydrique
[Vedettes matières IGN] Végétation et changement climatiqueRésumé : (auteur) Forest ecosystems are known for their capacity to retain and redistribute water. Nevertheless, even in some forested watersheds, prolonged or intense rainfall events often exceed the retention threshold of the system, generating accelerated runoff. Surface microrelief is an important attribute of forest ecosystems that often act to mediate potential runoff. In most natural forests, the soil surface is typically unevenly broken with pit and mound microrelief, formed by both historical and recent tree uprooting events. In managed forests, however, tree uprooting is traditionally seen as undesirable. The systematic repression of this process may lead to gradual loss of microrelief. To date, little attention has been paid to the impacts of the pit-mound microrelief, or its absence, on forest hydrology. Restoration of naturally undulating microrelief in managed forests can help to accentuate water retention and mitigate runoff, while reducing drought stress and reinforcing forest productivity and resilience.
This paper summarizes the literature and presents insights on the effects of tree uprooting on the microrelief of forest soils and forest hydrology, focusing on its consequences to water retention, tree water supply, and forest health. Furthermore, we explore the mechanisms and possible consequences of the long-term repression of these processes in intensively managed forests, with implications for forest management and further research.Numéro de notice : A2017-250 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2017.02.048 En ligne : https://doi.org/10.1016/j.foreco.2017.02.048 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85233
in Forest ecology and management > vol 393 (1 June 2017) . - pp 40 - 51[article]TM-Based SOC models augmented by auxiliary data for carbon crediting programs in semi-arid environments / Salahuddin M. Jaber in Photogrammetric Engineering & Remote Sensing, PERS, vol 83 n° 6 (June 2017)
[article]
Titre : TM-Based SOC models augmented by auxiliary data for carbon crediting programs in semi-arid environments Type de document : Article/Communication Auteurs : Salahuddin M. Jaber, Auteur ; Mohammed I. Al-Qinna, Auteur Année de publication : 2017 Article en page(s) : pp 447 - 457 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications de télédétection
[Termes IGN] analyse comparative
[Termes IGN] données auxiliaires
[Termes IGN] image Landsat-TM
[Termes IGN] Jordanie
[Termes IGN] matière organique
[Termes IGN] prédiction
[Termes IGN] sol
[Termes IGN] teneur en carbone
[Termes IGN] zone semi-arideRésumé : (Auteur) This study aimed at testing the hypothesis that augmenting Landsat TM-based models for predicting soil organic carbon (SOC) with auxiliary data about variables that might affect the spatial distribution of SOC might improve the predictability of these models in the Zarqa Basin in Jordan (a typical semi-arid watershed) and enable them to be used for implementing carbon crediting programs in semi-arid environments. Six modeling procedures, namely stepwise regression, partial least squares, recursive partitioning analysis, screening regression analysis, artificial neural networks, and combined models, were calibrated and validated for the basin and for the land cover types that exist in the basin. Although none of the developed models was powerful for predicting SOC, artificial neural networks models were more applicable specifically in agricultural lands. However, the margins of error associated with the best models were high, and hence hindered the applicability of these models in carbon crediting programs in semi-arid environments. Numéro de notice : A2017-350 Affiliation des auteurs : non IGN Thématique : IMAGERIE Nature : Article DOI : 10.14358/PERS.83.6.447 En ligne : https://doi.org/10.14358/PERS.83.6.447 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=85635
in Photogrammetric Engineering & Remote Sensing, PERS > vol 83 n° 6 (June 2017) . - pp 447 - 457[article]
Titre : Development of habitation maps for allergenic plants in Europe Type de document : Mémoire Auteurs : Juliette Delannoy, Auteur Editeur : Champs-sur-Marne : Ecole nationale des sciences géographiques ENSG Année de publication : 2017 Importance : 42 p. Format : 21 x 30 cm Note générale : Bibliographie
Rapport de projet pluridisciplinaire, cycle Ingénieur 2e annéeLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Ecologie
[Termes IGN] carte de la végétation
[Termes IGN] diagramme
[Termes IGN] format GeoTIFF
[Termes IGN] habitat d'espèce
[Termes IGN] pédologie locale
[Termes IGN] Python (langage de programmation)
[Termes IGN] QGIS
[Termes IGN] surveillance sanitaireIndex. décimale : PROJET Mémoires : Rapports de projet - stage des ingénieurs de 2e année Résumé : (Auteur) Le rapport présenté par la suite concerne la création de cartes d’habitation d’espèces allergènes en Europe. Mon travail s’est basé sur des cartes et inventaires déjà existants concernant l’occupation des sols et la présence d’espèce ainsi que sur des connaissances météorologiques. Premièrement, la création de diagrammes a permis l’étude d’après les données existantes de la répartition des espèces allergènes en fonction du type de sol et de la zone géographique. Cela a ensuite permis de déterminer le coefficient de présence moyenne d’une espèce dans un certain lieu géographique et biophysique. Ces coefficients sont ensuite utilisés pour l’élaboration de cartes d’habitation pour différentes espèces allergènes. L’objectif générale est donc la création des cartes, avec pour difficulté principale la détermination des coefficients représentant la présence de l’espèce. L’ensemble du processus se divise en deux grandes parties : l’obtention de diagrammes aidant à déterminer les coefficients de présence moyenne dans une certaine zone et l’obtention de cartes dans le monde entier s’appuyant sur les coefficients donnés par l’opérateur, issus de la première partie du processus. L’ensemble du projet a été mené avec le logiciel de programmation Python et avec le logiciel de système d’information géographique libre QGIS. Les formats principalement utilisés sont Geotiff et Netcdf. Note de contenu : Introduction
1. Selection of the data sets
1.1 Allergenic species
1.2 Type of inventories
1.3 Data sets used for the study
2. Grids for studying the maps
2.1 Choice of zones
2.2 Link between presence of species and type of land
3. Determination of the presence of species according to the type of land
3.1 Statistics of the distribution of the species among each type of land
3.2 Getting coefficients from histograms
4. Getting map of species from coefficients
4.1 Creating map of Europe thanks to coefficients
4.2 Examining the results
4.3 Applying to other geographical zones
ConclusionNuméro de notice : 22804 Affiliation des auteurs : non IGN Thématique : FORET/GEOMATIQUE Nature : Mémoire de projet pluridisciplinaire Organisme de stage : Finnish Meteorological Institute FMI Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=87852 Réservation
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Titre : Monitoring rock glaciers by combining photogrammetric and GNSS-based methods Type de document : Thèse/HDR Auteurs : Fabian Neyer, Auteur Editeur : Zurich : Schweizerischen Geodatischen Kommission / Commission Géodésique Suisse Année de publication : 2017 Autre Editeur : Zurich : Eidgenossische Technische Hochschule ETH - Ecole Polytechnique Fédérale de Zurich EPFZ Collection : Geodätisch-Geophysikalische Arbeiten in der Schweiz, ISSN 0257-1722 num. 99 Importance : 174 p. Format : 21 x 30 cm ISBN/ISSN/EAN : 978-3-908440-45-1 Note générale : bibliographie
thesis submitted to attain the degree of doctor of sciences of ETH ZurichLangues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] Alpes centrales
[Termes IGN] champ de vitesse
[Termes IGN] collocation par moindres carrés
[Termes IGN] déformation de la croute terrestre
[Termes IGN] données localisées 3D
[Termes IGN] glacier
[Termes IGN] image terrestre
[Termes IGN] matrice de covariance
[Termes IGN] pergélisol
[Termes IGN] reconstruction 3D
[Termes IGN] rocher
[Termes IGN] série temporelle
[Termes IGN] SuisseIndex. décimale : 30.60 Géodésie spatiale Résumé : (auteur) Rock glaciers are creeping landforms of perennially frozen ground and belong to the permafrost creeping phenomena. They are mainly composed of rock debris that accumulate in areas of high natural erosion. Ice particles between the rocks cause the moving accumulation in steep terrain to dynamically flow downslope. In the Alpine region, these morphological landforms mainly occur at north-facing mountain slopes in high altitudes above the forest boundary and are known for their sensitivity to climate change.
For several decades, rock glaciers have been monitored for scientific aims, while advances in surveying technologies increased the interest in such studies since the 1990s. Modern technologies in remote sensing (e.g., airborne imagery or satellite-based measurement techniques) are often combined with measurements from field campaigns, i.e., measurements taken directly on a rock glacier (e.g., GNSS, laser-scanning, ground temperature measurements, etc). The high-level goal is to enhance the process understanding, especially with respect to the changing climate: various studies indicate an extended risk of slope failures in steep frozen bedrock due to the global temperature increase. Early recognition of increased activities help to inform local authorities in the endangered areas about the potential hazard before such an event.
The present work is part of the X-Sense project (Nano-Tera.ch), with an interdisciplinary team of scientists that build and operate new low-cost devices for data acquisition, develop new data processing pipelines and algorithms for evaluation, and also gain new insight of natural processes in these regions. Autonomous measurement systems, developed within other work packages in the X-Sense project, observe different permafrost creep areas with high resolution in space and time. Combined with multi-year observations, the derived surface motions are used to obtain an improved process understanding.
This work focuses on the photogrammetric image processing in order to retrieve precise surface displacement estimates. More precisely, image sequences, acquired with two permanently installed commercial digital single-reflex cameras, are used to measure topographic changes in the observed permafrost area. By the combination with high resolution GNSS positioning results, the goal is to obtain precise time series of moving rock boulders at different positions within the field of view. Challenges arising from the combination of different data sets, the development of an automatic processing pipeline, and an improvement of the processing strategy in general, are the main tasks of this thesis.
The study site is the bordering area above the Grabengufer rock glacier (Mattervalley VS, Switzerland), known as the Grabengufer rock slide. Local topographic conditions allowed only a partially good installation geometry for the photogrammetric reconstruction. With respect to a 3D reconstruction without the use of GNSS coordinates, an accuracy increase of about one order of magnitude could be achieved in case these high-precision solutions were integrated. More specifically, respective standard deviations for the East, North, and Height components of 6, 5, and 2 cm were achieved. The stated accuracy, maintained throughout the measurement period of nearly four years (summer months), was obtained in an area of approximately 80m×80 m, with a mean distance of 80 m from the two cameras.
Position time series of moving rock boulders were filtered using the principles of collocation. Analyzing the correlation characteristics of the stochastic signal, an optimal correlation length was computed and used to extract relevant signals from the noise contaminated time series. Velocity was directly estimated as a derived quantity in the collocation process. Furthermore, the techniques of the adaptive collocation approach is presented. This iterative method uses the principles of a dynamically adjusting anisotropic covariance metric. In an example of 2-dimensional velocity fields it is shown that regional compression and extension areas can be extracted.
Results indicate that the observed permafrost area has experienced a mean annual acceleration of about 0.1m/Year between the years 2013 and 2015. During the late summer months of 2015, a prominent temporal acceleration was observed. The mean displacement rate was found to be 0.67m/year, whereas the 3-dimensional displacement is dominated by a translation following the gliding surface. An area in the front of the observed field of view was found to have higher displacement rates, especially during the late summer months, thus it detaches from the otherwise relatively homogeneous flow field.
The methods and principles presented in this work show the potential of monitoring permafrost surface displacements using permanently installed optical cameras in combination with positioning results from permanently mounted GNSS stations. These principles can easily be transfered to other monitoring applications and thus contribute to a better understanding of such processes.Note de contenu : 1 Introduction
2 Study Site
3 Image-Based Displacement Estimation
4 Object Point Reconstruction
5 Collocation for Time Series Analysis
6 Results
7 Conclusions
8 OutlookNuméro de notice : 17458 Affiliation des auteurs : non IGN Autre URL associée : https://doi.org/10.3929/ethz-a-010865360 Thématique : IMAGERIE Nature : Thèse étrangère Note de thèse : thèse : Sciences : ETHZ : 2016 DOI : 10.3929/ethz-a-010865360 En ligne : https://www.sgc.ethz.ch/sgc-volumes/sgk-99.pdf Format de la ressource électronique : URL Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89683 Réservation
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Code-barres Cote Support Localisation Section Disponibilité 17458-01 33.60 Livre Centre de documentation Photogrammétrie - Lasergrammétrie Disponible Improving the design of long-term monitoring experiments in forests: a new method for the assessment of local soil variability by combining infrared spectroscopy and dendrometric data / Emila Akroume in Annals of Forest Science, vol 73 n° 4 (December 2016)
[article]
Titre : Improving the design of long-term monitoring experiments in forests: a new method for the assessment of local soil variability by combining infrared spectroscopy and dendrometric data Type de document : Article/Communication Auteurs : Emila Akroume, Auteur ; Bernd Zeller, Auteur ; Marc Buée, Auteur ; Philippe Santenoise, Auteur ; Laurent Saint André, Auteur Année de publication : 2016 Article en page(s) : pp 1005 - 1013 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Termes IGN] dendrométrie
[Termes IGN] placette d'échantillonnage
[Termes IGN] rayonnement infrarouge moyen
[Termes IGN] sol forestier
[Termes IGN] spectroscopie
[Termes IGN] surveillance forestière
[Termes IGN] variabilité
[Vedettes matières IGN] Ecologie forestièreRésumé : (Auteur) Near- and mid-infrared spectroscopy allows for the detection of local patterns of forest soil properties. In combination with dendrometric data, it may be used as a prospective tool for determining soil heterogeneity before setting up long-term forest monitoring experiments.
Context : Forest soils and stands generally exhibit higher spatial heterogeneity than other terrestrial ecosystems. This variability needs be taken into account before setting up long-term forest monitoring experiments to avoid multiple interactions between local heterogeneity and the factors tested in the experiment.
Aims : We hypothesized that raw near- and mid-infrared spectra can be used as an integrated proxy of a large set of soil properties. The use of this method, in combination with dendrometric data, should provide a quick and cost-effective tool for optimizing the design of experimental forest sites.
Methods : We assessed the local soil heterogeneity at 11 experimental sites in oak and beech stands, which belong to a new forest long-term ecological research (LTER) network. We used near- and mid-infrared spectroscopy in soil and litter samples. The spectra were subjected to principal components analyses (PCA) to determine the intra-site variability of the soil and litter layers.
Results : Based on mapped PCA coordinates and basic dendrometric data, it was possible to design the experiment and minimize the interactions between the treatment layout and the tested variables. The method was validated with chemical analyses of the soil. No interaction was detected at the set-up of the experiment between the treatment layout and chemical soil properties (C, N, C/N ratio, pH, CEC, Al, Mg, P2O5, Fe, Mn, Na, and K).
Conclusion : Near-infrared (NIR) and mid-infrared (MIR) spectroscopy is a useful tool for characterizing the overall heterogeneity of soil chemical properties. It can be used without any preliminary calibration. In combination with dendrometric data, it provides a reliable method for optimizing LTER plots in different types of ecosystems.Numéro de notice : A2016--012 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1007/s13595-016-0572-3 Date de publication en ligne : 31/08/2016 En ligne : https://doi.org/10.1007/s13595-016-0572-3 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=83858
in Annals of Forest Science > vol 73 n° 4 (December 2016) . - pp 1005 - 1013[article]Optimizing the bioindication of forest soil acidity, nitrogen and mineral nutrition using plant species / Paulina E. Pinto in Ecological indicators, vol 71 (December 2016)PermalinkEstimating the rainfall erosivity for management planning in the Eastern Desert, Egypt / Kh. M. Darwish in Geocarto international, Vol 31 n° 9 - 10 (October - November 2016)PermalinkSilvicultural climatic turning point for European beech and sessile oak in Western Europe derived from national forest inventories / Klara Dolos in Forest ecology and management, vol 373 (1 August 2016)PermalinkLes sols forestiers, puits de méthane : un service écosystémique méconnu / Daniel Epron in Revue forestière française, vol 68 n° 4 (juillet 2016)PermalinkAbove- and belowground tree biomass models for three mangrove species in Tanzania: a nonlinear mixed effects modelling approach / Marco Andrew Njana in Annals of Forest Science, vol 73 n° 2 (June 2016)PermalinkTree species identity mediates mechanisms of top soil carbon sequestration in a Norway spruce and European beech mixed forest / Enrique Andivia in Annals of Forest Science, vol 73 n° 2 (June 2016)PermalinkAssessment of the cover changes and the soil loss potential in European forestland: First approach to derive indicators to capture the ecological impacts on soil-related forest ecosystems / P. Borrelli in Ecological indicators, vol 60 (January 2016)PermalinkPetit lexique de pédologie / Denis Baize (2016)PermalinkResidual vegetation patches within natural boreal wild fires: Characterizing by pattern metrics, land cover expec tations and proximity to firebreak features / Yikalo H. Araya in Geomatica, vol 69 n° 4 (December 2015)PermalinkExceedance of critical loads and of critical limits impacts tree nutrition across Europe / Peter Waldner in Annals of Forest Science, vol 72 n° 7 (October 2015)Permalink