High altitude lakes in the French Alps : Contribution to the high altitude lakes and mountain environments knowledge since the end of lateglacia

• Main Author: Édouard, Jean-Louis
• Other Authors: Université Joseph Fourier - Grenoble 1 (UJF), Université Joseph Fourier Grenoble I, Huguette Vivian
• Format: Thesis
• Language: French
• Published: HAL CCSD 1994
• Subjects: Lake; Physical Geography; mountains; hydrology; water regime; limnology; mountain lake; typology; thermal regime; caractéristiques physico-chimiques (ou physiques et chimiques); bathymetric map; lake morphometry; geomorphology; palaeoenvironment; upper forest limit fluctuation; Quaternary; glaciation; glacier; glacier fluctuations; Late Glacial; Holocene; Little Ice Age; climate; climatic changes//dendrochronology; tree-rings; tree-ring dating; radiocarbon dating; subfossil wood; Mountain pine; cembra pine//France; French Alps; Vanoise; Ecrins; Mercantour; Briançonnais; Grandes Rousses; Taillefer; Belledonne; Lac; Lac de montagne; . hydrologie; geomorphologie; geologie; Paléoenvironnement; Limnologie; France. Isère; Alpes; Géographie physique; montagne; régime hydrologique; Ice Sheet
• Online Access: https://hal.archives-ouvertes.fr/tel-03188574/file/These_1994_lacs_altitude_alpes_JL_Edouard.pdf; https://hal.archives-ouvertes.fr/tel-03188574

The aim of the thesis is the study of the reconstitution of the high altitude lakes story in a changing environment since 10 000 years and the study of the present state of the lakes. The first part explains the story of lakes in high mountains. In the first chapter, the localisation of the lakes is studied at the end of the late-glacial (younger Dryas, about 10200 BP). The second chapter shows the environment changes with the retreat of the glaciers and with the timberline fluctuations during the Holocene period. The two following chapters 3 and 4 describe the interactions between lakes and glaciers (formation-disappearance) during the historic period (little ice age, Contemporary period).Two methods are used to study these environment modifications : geomorphology analysis and dendrochronology applied to subfossil woods well-preserved in peats and lakes, then compared with other palaeoecological approaches (palynology, palaeoentomology, macro-remain, pedoanthracology). The second part is a synthesis about the present state of the high altitude lakes from new measures. First, in chapter 1, the lakes are studied astheir place in mountain society (dangerous lakes, turism, water resources.). Then, in chapter 2, the structure of the database and the methods of measures are developed. Four following chapters describe the lake diversity in the French Alps : location, identification and inventory, morphometry and geomorphology (chapter 3), hydrology and thermic variations, snow cover and ice sheet, its duration (chapters 4 and 5), transparence, mineralisation, oxygenation (chapter 6) abstracted in a typology (multivariate analysis) which is developed in the chapter 7. An atlas gathers together the bathymetric maps and photographs of 43 lakes among the lakes which are studied by the author. L'objectif de cette thèse est de reconstituer l'histoire des lacs d'altitude dans un environnement marqué par des changements profonds depuis 10000 ans et de proposer une vue d'ensemble de l'état actuel des lacs d'altitude dans ...