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Microtopography and ecology of pit-mound structures in second-growth versus old-growth forests / Audrey Barker Plotkin in Forest ecology and management, vol 404 (15 November 2017)
[article]
Titre : Microtopography and ecology of pit-mound structures in second-growth versus old-growth forests Type de document : Article/Communication Auteurs : Audrey Barker Plotkin, Auteur ; Peter Schoonmaker, Auteur ; Bennet Leon, Auteur ; David Foster, Auteur Année de publication : 2017 Article en page(s) : pp 14 - 23 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Végétation
[Termes IGN] analyse comparative
[Termes IGN] Betula (genre)
[Termes IGN] forêt ancienne
[Termes IGN] microtopographie
[Termes IGN] richesse floristique
[Termes IGN] structure d'un peuplement forestier
[Termes IGN] tempêteRésumé : (auteur) Pit and mound microtopography is an important structural component of most forests, influencing soil processes and habitat diversity. These features have diminished greatly in northeastern U.S. forests since European settlement, as a result of the history of repeated logging, land-clearance followed by reforestation, and the smaller size of trees (and therefore windthrow features) comprising the prevailing second-growth forests. Despite the potential importance of this region-wide shift in forest microtopography on ecosystem structure and function, the differences in pit and mound size, distribution, and longevity between second-growth and old-growth forests are unexplored. Likewise, although many studies demonstrate that mounds and/or pits are hotspots for tree regeneration there is scant information about whether location on a mound or pit affects tree survival and growth beyond the seedling stage, or whether microtopographic regeneration patterns differ in old-growth and second-growth forests.
We compare a simulated hurricane experiment initiated in 1990 in second-growth forest (the pulldown) and an old-growth forest that was blown down by a hurricane in 1938 (Pisgah) to examine differences in pit-mound microtopography and ecology between second-growth and old-growth forest. At Pisgah, fewer, larger mounds comprised a similar areal coverage as at the pulldown. Repeated measurements of individual pit-mound structures in the pulldown revealed that pit infill proceeded more rapidly than mound erosion. Mound area increased but height decreased over time as soil from the mound tops eroded and spread around the mound base. Although 40% of mounds in the pulldown were >1 m tall immediately after the manipulation (maximum of 2.9 m), after 25 years, maximum mound height was 0.9 m. In contrast, 11% of mounds at Pisgah remained >1 m tall in 1989, 50 years after blowdown. At both sites, trees, especially Betula spp., were disproportionately found on mounds. Fewer trees than expected grew in pits at Pisgah. Tree mortality was somewhat higher on mounds and pits than on other substrates. As a mechanism to increase stand-level tree diversity, windthrow may be more critical in old-growth forests, in which niches for early-mid successional species are few, than in second-growth forest, in which early-mid successional species already comprise the majority of the trees. Pit-mound structures are a diminished component of second-growth forest, and silvicultural techniques designed to restore old-growth characteristics could include measures to preserve and enhance pit-mound features, and to cultivate large-diameter trees that will eventually create the large, long-lasting pit-mounds of the future.Numéro de notice : A2017-806 Affiliation des auteurs : non IGN Thématique : FORET Nature : Article DOI : 10.1016/j.foreco.2017.08.012 En ligne : https://doi.org/10.1016/j.foreco.2017.08.012 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=89243
in Forest ecology and management > vol 404 (15 November 2017) . - pp 14 - 23[article]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]A new adaptive method to filter terrestrial laser scanner point clouds using morphological filters and spectral information to conserve surface micro-topography / Emilio Rodríguez-Caballero in ISPRS Journal of photogrammetry and remote sensing, vol 117 (July 2016)
[article]
Titre : A new adaptive method to filter terrestrial laser scanner point clouds using morphological filters and spectral information to conserve surface micro-topography Type de document : Article/Communication Auteurs : Emilio Rodríguez-Caballero, Auteur ; A. Afana, Auteur ; S. Chamizo, Auteur ; et al., Auteur Année de publication : 2016 Article en page(s) : pp 141 – 148 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Lasergrammétrie
[Termes IGN] données lidar
[Termes IGN] filtrage numérique d'image
[Termes IGN] microtopographie
[Termes IGN] modèle numérique de terrain
[Termes IGN] semis de points
[Termes IGN] télémétrie laser terrestreRésumé : (auteur) Terrestrial laser scanning (TLS), widely known as light detection and ranging (LiDAR) technology, is increasingly used to provide highly detailed digital terrain models (DTM) with millimetric precision and accuracy. In order to generate a DTM, TLS data has to be filtered from undesired spurious objects, such as vegetation, artificial structures, etc., Early filtering techniques, successfully applied to airborne laser scanning (ALS), fail when applied to TLS data, as they heavily smooth the terrain surface and do not retain their real morphology. In this article, we present a new methodology for filtering TLS data based on the geometric and radiometric properties of the scanned surfaces. This methodology was built on previous morphological filters that select the minimum point height within a sliding window as the real surface. However, contrary to those methods, which use a fixed window size, the new methodology operates under different spatial scales represented by different window sizes, and can be adapted to different types and sizes of plants. This methodology has been applied to two study areas of differing vegetation type and density. The accuracy of the final DTMs was improved by ∼30% under dense canopy plants and over ∼40% on the open spaces between plants, where other methodologies drastically underestimated the real surface heights. This resulted in more accurate representation of the soil surface and microtopography than up-to-date techniques, eventually having strong implications in hydrological and geomorphological studies. Numéro de notice : A2016-583 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.isprsjprs.2016.04.004 En ligne : https://doi.org/10.1016/j.isprsjprs.2016.04.004 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=81724
in ISPRS Journal of photogrammetry and remote sensing > vol 117 (July 2016) . - pp 141 – 148[article]Evaluation of structure from motion for soil microtopography measurement / Sayjro K. Nouwakpo in Photogrammetric record, vol 29 n° 147 (September - November 2014)
[article]
Titre : Evaluation of structure from motion for soil microtopography measurement Type de document : Article/Communication Auteurs : Sayjro K. Nouwakpo, Auteur ; Mike R. James, Auteur ; Mark A. Weltz, Auteur ; et al., Auteur Année de publication : 2014 Article en page(s) : pp 297 - 316 Note générale : Bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] érosion
[Termes IGN] microtopographie
[Termes IGN] semis de points
[Termes IGN] structure-from-motionRésumé : (Auteur) Recent developments in low-cost structure-from-motion (SfM) technologies offer new opportunities for geoscientists to acquire high-resolution soil microtopography data at a fraction of the cost of conventional techniques. However, these new methodologies often lack easily accessible error metrics and hence are difficult to evaluate. In this research, a framework was developed to evaluate a SfM approach for soil microtopography measurement through assessment of uncertainty sources and quantification of their potential impact on overall 3D reconstruction. Standard deviations of camera interior orientation parameters estimated from SfM self-calibration within five different soil surface models were several orders of magnitude larger than precisions expected from pattern-based camera calibration. Sensitivity analysis identified the principal point position as the dominant source of calibration-induced uncertainty. Overall, surface elevation values estimated from both technologies were similar in magnitude with a root mean square (RMS) of elevation difference of 0·2 mm. Nevertheless, the presence of deformation in either SfM or traditional photogrammetric point clouds highlights the importance of quality assurance safeguards (such as a judicious choice of control points) in SfM workflows for soil microtopography applications. Numéro de notice : A2014-490 Affiliation des auteurs : non IGN Thématique : IMAGERIE/POSITIONNEMENT Nature : Article DOI : 10.1111/phor.12072 Date de publication en ligne : 18/09/2014 En ligne : https://doi.org/10.1111/phor.12072 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=74079
in Photogrammetric record > vol 29 n° 147 (September - November 2014) . - pp 297 - 316[article]Exemplaires(1)
Code-barres Cote Support Localisation Section Disponibilité 106-2014031 RAB Revue Centre de documentation En réserve L003 Disponible An advanced photogrammetric method to measure surface roughness: Application to volcanic terrains in the Piton de la Fournaise, Reunion Island / Frédéric Bretar in Remote sensing of environment, vol 135 (August 2013)
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Titre : An advanced photogrammetric method to measure surface roughness: Application to volcanic terrains in the Piton de la Fournaise, Reunion Island Type de document : Article/Communication Auteurs : Frédéric Bretar, Auteur ; Mélanie Arab-Sedze, Auteur ; J. Champion, Auteur ; Marc Pierrot-Deseilligny , Auteur ; Essam Heggy, Auteur ; Stéphane Jacquemoud, Auteur Année de publication : 2013 Article en page(s) : pp 1 - 11 Note générale : bibliographie Langues : Anglais (eng) Descripteur : [Vedettes matières IGN] Applications photogrammétriques
[Termes IGN] anisotropie
[Termes IGN] appariement d'images
[Termes IGN] lave
[Termes IGN] microtopographie
[Termes IGN] Piton de la Fournaise (volcan)
[Termes IGN] Réunion, île de la
[Termes IGN] rugosité
[Termes IGN] volcanRésumé : (auteur) We present a rapid in situ photogrammetric method to characterize surface roughness by taking overlapping photographs of a scene. The method uses a single digital camera to create a high-resolution digital terrain model (pixel size of ~1.32 mm) by means of a free open-source stereovision software. It is based on an auto-calibration process, which calculates the 3D geometry of the images, and an efficient multi-image correlation algorithm. The method is successfully applied to four different volcanic surfaces—namely, a′a lava flows, pahoehoe lava flows, slabby pahoehoe lava flows, and lapilli deposits. These surfaces were sampled in the Piton de la Fournaise volcano (Reunion Island) in October, 2011, and displayed various terrain roughnesses. Our in situ measurements allow deriving digital terrain models that reproduce the millimeter-scale height variations of the surfaces over about 12 m2. Five parameters characterizing surface topography are derived along unidirectional profiles: the root-mean-square height (ξ), the correlation length (Lc), the ratio Zs = ξ2/Lc, the tortuosity index (τ), and the fractal dimension (D). Anisotropy in the surface roughness has been first investigated using 1-m-long profiles circularly arranged around a central point. The results show that Lc, Zs and D effectively catch preferential directions in the structure of bare surfaces. Secondly, we studied the variation of these parameters as a function of the profile length by drawing random profiles from 1 to 12 m in length. We verified that ξ and Lc increase with the profile length and, therefore, are not appropriate to characterize surface roughness variation. We conclude that Zs and D are better suited to extract roughness information for multiple eruptive terrains with complex surface texture. Numéro de notice : A2013-791 Affiliation des auteurs : LASTIG MATIS+Ext (2012-2019) Thématique : IMAGERIE Nature : Article nature-HAL : ArtAvecCL-RevueIntern DOI : 10.1016/j.rse.2013.03.026 Date de publication en ligne : 10/04/2013 En ligne : http://dx.doi.org/10.1016/j.rse.2013.03.026 Format de la ressource électronique : URL article Permalink : https://documentation.ensg.eu/index.php?lvl=notice_display&id=80084
in Remote sensing of environment > vol 135 (August 2013) . - pp 1 - 11[article]Restitution de la rugosité des surfaces par photogrammétrie à partir des photographies prises au sol sans contraintes / Zana Lak (2013)PermalinkClose range stereophotogrammetry and video imagery analyses in soil ecohydrology modelling / Maria J. Rossi in Photogrammetric record, vol 27 n° 137 (March - May 2012)PermalinkApplying close range digital photogrammetry in soil erosion studies / B. Heng in Photogrammetric record, vol 25 n° 131 (September - November 2010)PermalinkAssessment of erosion, deposition and rill development on irregular soil surfaces using close range digital photogrammetry / G. Gessesse in Photogrammetric record, vol 25 n° 131 (September - November 2010)PermalinkContribution d'un système Lidar pour la reconstruction de la trame urbaine d'un village médiéval abandonné / Nicola Masini in Photo interprétation, European journal of applied remote sensing, vol 46 n° 1 (mars 2010)Permalink