A lichenometric growth curve in the French Alps: Ailefroide and Veneon valleys; Massif des Ecrins
| Autor: | N. Jacob, M. Baumgart-Kotarba, Stanisław Kędzia, C. Tsao, J.P. Bravard, Adam Kotarba, M. Chardon, P. Pech, Z. Raczkowska, Vincent Jomelli |
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| Přispěvatelé: | Laboratoire de géographie physique : Environnements Quaternaires et Actuels (LGP), Université Paris 1 Panthéon-Sorbonne (UP1)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12)-Université Panthéon-Sorbonne (UP1) |
| Jazyk: | francouzština |
| Rok vydání: | 2003 |
| Předmět: |
010506 paleontology
010504 meteorology & atmospheric sciences Range (biology) [SDE.MCG]Environmental Sciences/Global Changes 01 natural sciences [SHS]Humanities and Social Sciences Lichen [SDU.ENVI]Sciences of the Universe [physics]/Continental interfaces environment ComputingMilieux_MISCELLANEOUS 0105 earth and related environmental sciences Earth-Surface Processes geography geography.geographical_feature_category biology Growth curve (biology) Massif 15. Life on land biology.organism_classification Geophysics Homogeneous Moraine [SDU]Sciences of the Universe [physics] [SDE]Environmental Sciences Rhizocarpon Period (geology) Physical geography Geology |
| Zdroj: | Geodinamica Acta Geodinamica Acta, Taylor & Francis, 2003, 16 (2-6), pp.187-193. ⟨10.1016/j.geoact.2003.07.001⟩ Geodinamica Acta, 2003, 16 (2-6), pp.187--193. ⟨10.1016/j.geoact.2003.07.001⟩ |
| ISSN: | 0985-3111 |
| Popis: | Today there is only one lichenometric curve in the French Alps for the Haute Ubaye valley. This study presents a growth curve constructed for Rhizocarpon subgenus Rhizocarpon of the Ailefroide and Veneon valleys, which are located in the Massif des Ecrins. In order to establish this curve, we used the modal values from tests carried out on the five largest lichens, the mean values of the five largest lichens and each single biggest lichen. The last two methods have been rejected for statistical and theoretical reasons. The 27 dated points on which the curve is based have a shared and homogeneous set-up on the period corresponding to the last 150 years. Fourteen points come from man-made structures and 13 from moraines. According to our results, two separate curves have been drawn corresponding to two climatic mountainous ranges: a low lichen factor (20.7 mm/100 years) for forest ranges and a mean lichen factor (28.47 mm/100 years) for alpine belts (above 2000 m a.s.l.). The differences in lichen growth rates are caused by methodological and environmental differences. In comparison with the two existing curves near the Massif des Ecrins, one in the Haute Ubaye and the other in the Val d’Aosta (Italian Alps), our lichen factors are very low. This may be due to the fine-grained texture of the local granites, low solar radiation and dry conditions during the summer. This variation in the lichen factor confirms the need to establish growth curves for each specific geographic and altitudinal range. |
| Databáze: | OpenAIRE |
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