Sediment-moss interactions on a temperate glacier: Falljökull, Iceland

• Published in: Annals of Glaciology
• Main Authors: Porter, P.R., Evans, A.J., Hodson, A.J., Lowe, A., Crabtree, M.D.
• Other Authors: Department of Human and Environmental Sciences, School of Life and Medical Sciences, Health & Human Sciences Research Institute, Geography, Environment and Agriculture
• Language: English
• Published: 2008
• Subjects: Falljökull; Vatnajökull; Annals of Glaciology; glacier; Ice cap; Iceland
• Online Access: http://hdl.handle.net/2299/9455; http://www.scopus.com/inward/record.url?scp=45249088130&partnerID=8YFLogxK

Full text of this article can be found at: http://www.igsoc.org/annals/ Copyright IGS. DOI:10.3189/172756408784700734 We present the results of preliminary investigations of globular moss growth on the surface of Falljökull, a temperate outlet glacier of the Vatnajökull ice cap, southern Iceland. Supraglacial debris has provided a basis for moss colonization, and several large (>500 m2) patches of moss growth (Racomitrium spp.) are observed on the surface of the glacier. Each area of moss-colonized supraglacial debris shows a downslope increase in sphericity and moss cushion size and a decrease in percentage surface coverage of moss-colonized and bare clasts. It is suggested that moss growth on supraglacial debris allows preferential downslope movement of clasts through an associated increase in both overall mass and sphericity. Thermal insulation by moss cushions protects the underlying ice surface from melt, and the resulting ice pedestals assist in downslope sliding and toppling of moss cushions. The morphology and life cycle of supraglacial globular mosses is therefore not only closely linked to the presence and distribution of supraglacial debris, but also appears to assist in limited down-glacier transport of this debris. This research highlights both the dynamic nature of the interaction of mosses with supraglacial sedimentary systems and the need for a detailed consideration of their role within the wider glacial ecosystem. Peer reviewed