Contexte environnemental et colonisation végétale des moraines récentes : étude comparée de deux glaciers en versant nord et sud de la presqu'île de Brøgger, Svalbard (79°N).

• Main Author: Moreau, Myrtille
• Other Authors: Laboratoire de Géographie Physique et Environnementale (GEOLAB), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-Université Clermont Auvergne 2017-2020 (UCA 2017-2020 )-Université Clermont Auvergne (UCA)-Institut Sciences de l'Homme et de la Société (IR SHS UNILIM), Université de Limoges (UNILIM)-Université de Limoges (UNILIM)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: French
• Published: HAL CCSD 2005
• Subjects: Spitsberg; colonisation végétale; marge proglaciaire; mésoclimat; analyse de données; Spitsbergen; plant colonization; proglacial area; data analysis; [SHS.GEO]Humanities and Social Sciences/Geography; Arctic; Edithbreen; Svalbard; Arctique*; glacier
• Online Access: https://halshs.archives-ouvertes.fr/halshs-00468686

National audience Due to the global climatic changes which followed the Little Ice Age, most of the Arctic Glaciers are retreating. Thus, larger and larger areas become free for plant colonization. Such a process can be observed on Svalbard where the present study takes place; it concerns the front areas of two glaciers named Edithbreen and Austre Lovénbreen. Both of them are located on the Brøgger peninsula, (79°N); the first one is South facing whereas the second one is North facing. By means of systematic botanical releves aiming to sample the field, the relationship between ice smelting and plant colonization process is emphasized. Time is, of course, the main factor which determines the vegetation evolution in term of physiognomy and floristic composition. The phanerogams start to colonize the moraine after 20 years since the glacier has left. Everywhere, the floristic sequence is the same from the early pioneer stages until the mature ones. However, this process is not homogeneous and not only time dependent. The environment conditions are also important and their effect can be shown up at different scales. For instance, the south and north facing positions can be recognized as factors which determine some variations in the colonization process. Obviously, the local conditions are interfering with the general time dependent colonization process. Sous l'effet du réchauffement climatique qui a suivi le Petit Âge Glaciaire, la fonte des glaciers arctiques a libéré de nouveaux espaces conquis ensuite par la végétation. Le phénomène est bien marqué au Svalbard où la présente étude est conduite. Celle-ci concerne les marges de deux appareils, les glaciers Edithbreen et Austre Lovénbreen le premier est situé en façade sud, l'autre en façade nord de la presqu'île de Brøgger (79°N). Une analyse par relevés floristiques systématiques permet de mettre en relation les phases successives de retrait glaciaire et de colonisation végétale. Le temps est évidemment le facteur déterminant qui gouverne l'évolution de la ...