Effect of mass wasting on soil organic carbon storage and coastal erosion in permafrost environments Accelerated permafrost thaw under the warming Arctic climate can have a significant impact on Arctic landscapes. Areas underlain by permafrost store high amounts of soil organic carbon (SOC). Permafrost disturbances may contribute to increased release of carbon dioxide and methane to the atmosphere. Coastal erosion amplified through a decrease in Arctic sea ice extent may also mobilise SOC from permafrost. Large expanses of permafrost affected land are characterised by intense mass wasting processes such as solifluction active layer detachments and retrogressive thaw slumping. Our aim is to assess the influence of mass wasting on SOC storage and coastal erosion. We studied SOC storage on Herschel Island by analysing active layer and permafrost samples and compared non disturbed sites to those characterised by mass wasting. Mass wasting sites showed decreased SOC storage and material compaction whereas sites characterised by material accumulation showed increased storage. The SOC storage on Herschel Island is also significantly …