|
|
Fablet, R., Chaigneau, A., & Bertrand, S. (2014). Multiscale analysis of geometric planar deformations : application to wild animal electronic tracking and satellite ocean observation data. Ieee Transactions on Geoscience and Remote Sensing, 52(6), 3627–3636.
Résumé: The development of animal tracking technologies (including GPS and ARGOS satellite systems) and the increasing resolution of remote-sensing observations call for tools extracting and describing the geometric patterns along a track or within an image over a wide range of spatial scales. Whereas shape analysis has largely been addressed over the last decades, the multiscale analysis of the geometry of opened planar curves has received little attention. We here show that classical multiscale techniques cannot properly address this issue and propose an original wavelet-based scheme. To highlight the generic nature of our multiscale wavelet technique, we report applications to two different observation data sets, namely, wild animal movement paths recorded by electronic tags and satellite observations of sea-surface geophysical fields.
|
|
|
|
Jeanmougin, M., Leprieur, F., Lois, G., & Clergeau, P. (2014). Fine-scale urbanization affects Odonata species diversity in ponds of a megacity (Paris, France). Acta Oecologica-International Journal of Ecology, 59, 26–34.
Résumé: Current developments in urban ecology include very few studies focused on pond ecosystems, though ponds are recognized as biodiversity hotspots. Using Odonata as an indicator model, we explored changes in species composition in ponds localized along an urban gradient of a megacity (Paris, France). We then assessed the relative importance of local- and landscape-scale variables in shaping Odonata alpha-diversity patterns using a model-averaging approach. Analyses were performed for adult (A) and adult plus exuviae (AE) census data. At 26 ponds, we recorded 657 adults and 815 exuviae belonging to 17 Odonata species. The results showed that the Odonata species assemblage composition was not determined by pond localization along the urban gradient. Similarly, pond characteristics were found to be similar among urban, suburban and periurban ponds. The analyses of AE census data revealed that fine-scale urbanization (i.e., increased density of buildings surrounding ponds) negatively affects Odonata alpha-diversity. In contrast, pond localization along the urban gradient weakly explained the alpha-diversity patterns. Several local-scale variables, such as the coverage of submerged macrophytes, were found to be significant drivers of Odonata alpha-diversity. Together, these results show that the degree of urbanization around ponds must be considered instead of pond localization along the urban gradient when assessing the potential impacts of urbanization on Odonata species diversity This work also indicates the importance of exuviae sampling in understanding the response of Odonata to urbanization. (C) 2014 Elsevier Masson SAS. All rights reserved.
|
|
|
|
Anderson, P. S. L., Claverie, T., & Patek, S. N. (2014). Levers And Linkages: Mechanical Trade-Offs In A Power-Amplified System. Evolution, 68(7), 1919–1933.
Résumé: Mechanical redundancy within a biomechanical system (e. g., many-to-one mapping) allows morphologically divergent organisms to maintain equivalent mechanical outputs. However, most organisms depend on the integration of more than one biomechanical system. Here, we test whether coupled mechanical systems follow a pattern of amplification (mechanical changes are congruent and evolve toward the same functional extreme) or independence (mechanisms evolve independently). We examined the correlated evolution and evolutionary pathways of the coupled four-bar linkage and lever systems in mantis shrimp (Stomatopoda) ultrafast raptorial appendages. We examined models of character evolution in the framework of two divergent groups of stomatopods-“smashers” (hammer-shaped appendages) and “spearers” (bladed appendages). Smashers tended to evolve toward force amplification, whereas spearers evolved toward displacement amplification. These findings show that coupled biomechanical systems can evolve synergistically, thereby resulting in functional amplification rather than mechanical redundancy.
|
|
|
|
Avadí, Á., Vázquez-Rowe, I., & Freon, P. (2014). Eco-efficiency assessment of the Peruvian anchoveta steel and wooden fleets using the LCA+DEA framework. Journal of Cleaner Production, 70, 118–131.
Résumé: The Peruvian anchoveta fishery is currently targeted by a large fleet featuring a wide range of vessel sizes (segments), with highly variable capacities. In addition, the landings of the industrial fleet are used exclusively by the reduction industry, while those performed by small- and medium-scale vessels are destined mainly for direct human consumption. Despite these differences, the entire fleet is made up of purse seiners that perform similar operations when at sea. Therefore, the main aim of this study is to identify the differences in eco-efficiency between the different fleet segments in order to delve into the potential environmental improvements that could be attained through operational benchmarking. To this end, the combined use of Life Cycle Assessment (LCA) and Data Envelopment Analysis (DEA) was applied to the Peruvian anchoveta fleet. More specifically, a modified 5-step LCA + DEA method, whose particularities are broadly discussed throughout the study, was computed to obtain the desired operational benchmarks and, thereafter, estimate the target environmental gains. Results led to an average efficiency score of 86% throughout the segments, with a total of eight fleet segments out of 13 (62%) operating inefficiently. Nevertheless, no clear pattern was identified through the segments, although certain correlations with stock abundance, fuel use intensity, overcapacity and climatic conditions are discussed. Reduction in material inputs based on operational benchmarks translated into environmental gains that ranged from 26% to 53% for inefficient segments. Finally, it is expected that the findings in this study may aid stakeholders and policy makers when revising fuel use optimisation and overcapacity management strategies.
|
|
|
|
Robert, M., Dagorn, L., Bodin, N., Pernet, F., Arsenault-Pernet, E. J., & Deneubourg, J. L. (2014). Comparison of condition factors of skipjack tuna (Katsuwonus pelamis) associated or not with floating objects in an area known to be naturally enriched with logs. Canadian Journal of Fisheries and Aquatic Sciences = Journal Canadien des Sciences Halieutiques et A, 71(3), 472–478.
Résumé: Dans une région très peu modifiée par des dispositifs de concentration de poissons (DCP), le canal du Mozambique (naturellement riche en billes de bois, mais comptant peu de DCP), nous avons observé que l&8217;embonpoint de listao (Katsuwonus pelamis) associées à des objets flottants était plus faible que celui de leurs congénères nageant en bancs libres. Puisque ce résultat porte sur une zone analogue au milieu naturel avant l&8217;utilisation de DCP, il remet en question l&8217;interprétation d&8217;études antérieures voulant que cette différence reflète l&8217;incidence d&8217;un vaste déploiement de DCP sur les thonidés. Il est possible que, avant l&8217;utilisation de DCP, les thons associées aux billes de bois présentaient également un moins bon embonpoint que les thons nageant en bancs libres. Nos résultats semblent indiquer que la raison évolutive pour laquelle les thonidés sont associées à des objets flottants ne serait peut-être pas être reliée à des avantages trophiques à court terme, et d&8217;autres hypothèses (p. ex. l&8217;hypothèse du point de rencontre) sont invoquées pour expliquer ces résultats.
|
|
