Can Antarctica's shallow zoobenthos 'bounce back' from iceberg scouring impacts driven by climate change?. (16th April 2021)

• Record Type: Journal Article
• Authors: Zwerschke, Nadescha; Morley, Simon A.; Peck, Lloyd S.; Barnes, David K. A.
• Is Part Of: Global change biology. Volume 27:Number 13(2021)
• Page Start: 3157
• Page End: 3165
• Publication Date: 2021-04-16
• Subjects: benthos -- disturbance -- polar -- recovery -- resilience -- sea‐ice; Climatic changes -- Environmental aspects -- Periodicals; Troposphere -- Environmental aspects -- Periodicals; Biodiversity conservation -- Periodicals; Eutrophication -- Periodicals; 551.5
• DOI: 10.1111/gcb.15617
• Languages: English
• ISSNs: 1354-1013

Abstract

Abstract: All coastal systems experience disturbances and many across the planet are under unprecedented threat from an intensification of a variety of stressors. The West Antarctic Peninsula is a hotspot of physical climate change and has experienced a dramatic loss of sea‐ice and glaciers in recent years. Among other things, sea‐ice immobilizes icebergs, reducing collisions between icebergs and the seabed, thus decreasing ice‐scouring. Ice disturbance drives patchiness in successional stages across seabed assemblages in Antarctica's shallows, making this an ideal system to understand the ecosystem resilience to increasing disturbance with climate change. We monitored a shallow benthic ecosystem before, during and after a 3‐year pulse of catastrophic ice‐scouring events and show that such systems can return, or bounce back, to previous states within 10 years. Our long‐term data series show that recovery can happen more rapidly than expected, when disturbances abate, even in highly sensitive cold, polar environments. Abstract : Recovery from disturbance is fundamental to generation and maintenance of biodiversity and ecosystem functioning, but we know little about this in Antarctica. Climate change has resulted in less seasonal freezing of the sea surface (sea‐ice) around West Antarctica allowing icebergs to drift more and scour seafloor life there. We monitored sea‐ice duration and iceberg impacts for 20 years and linked those changes to animal community dynamics on the shallow seafloor. During 2007–2009 low sea‐ice caused an increase of iceberg impacts, in turn measurably impacting the animal community. It took 10 years after this catastrophic impact for the community to recover.