Changes of humus features along with a successional gradient of Rhododendron ferrugineum (L.) populations (subalpine level, northwestern Alps, France)

• Main Authors: Doche, B., Franchini, S., Pornon, A., Lemperiere, G.
• Other Authors: Laboratoire d'Ecologie Alpine (LECA), Université Joseph Fourier - Grenoble 1 (UJF)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Ecologie Terrestre (LET), Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2005
• Subjects: Bilberry spruce forest; nitrogen mineralization; ammonium nutrition; soil community; dynamics; nitrate; plants; heterogeneity; feedback; litter; [SDE.BE]Environmental Sciences/Biodiversity and Ecology; [SDV.BID]Life Sciences [q-bio]/Biodiversity; [SDV.EE]Life Sciences [q-bio]/Ecology; environment; Antarctic and Alpine Research; Arctic
• Online Access: https://hal.science/halsde-00294530; https://doi.org/10.1657/1523-0430(2005)037[0454:COHFAW]2.0.CO;2

International audience The modifications of humus characteristics as a result of the establishment and the increasing cover of Rhododendron ferrugineum L. (Ericaceae) in a subalpine meadow were studied in three sites in the northwestern French Alps corresponding to a west-east transect between wet and dry Alps ("Chaine de Belledonne," "Massif du Taillefer," "Brianconnais"). The physical and chemical parameters of humus and biological parameters were studied during the successive studies. As opposed to other Ericaceae heathlands on siliceous soils (Vaccinium sp., Erica sp., Calluna vulgaris), with an increasing Rhododendron cover, the humus structure changed while some other parameters remain stable or increased. The development of Rhododendron populations on calcareous soils (Brianconnais) with maintenance of a calcareous humus has never been checked before. The modifications of the Rhododendron environment under its canopy led to an improvement in its growth conditions (positive feedback).