Climate-driven regime shifts in Arctic marine benthos.
Climate warming can trigger abrupt ecosystem changes in the Arctic. Despite the considerable interest in characterizing and understanding the ecological impact of rapid climate warming in the Arctic, few long time series exist that allow addressing these research goals. During a 30-y period (1980-2010) of gradually increasing seawater temperature and decreasing sea ice cover in Svalbard, we document rapid and extensive structural changes in the rocky-bottom communities of two Arctic fjords. The most striking component of the benthic reorganization was an abrupt fivefold increase in macroalgal cover in 1995 in Kongsfjord and an eightfold increase in 2000 in Smeerenburgfjord. Simultaneous changes in the abundance of benthic invertebrates suggest that the macroalgae played a key structuring role in these communities. The abrupt, substantial, and persistent nature of the changes observed is indicative of a climate-driven ecological regime shift. The ecological processes thought to drive the observed regime shifts are likely to promote the borealization of these Arctic marine communities in the coming years.
Department of Arctic and Marine Biology, University of Tromsø, N-9037, Norway. susanne.kortsch@uit.no
Susanne
S
Kortsch
Raul
R
Primicerio
Frank
F
Beuchel
Paul E
PE
Renaud
João
J
Rodrigues
Ole Jørgen
OJ
Lønne
Bjørn
B
Gulliksen
D001110:Arctic Regions; D002980:Climate; D057231:Climate Change; D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods; D046448:Ice Cover / Q000382:microbiology; D016014:Linear Models; D008386:Marine Biology / Q000379:methods*; D000459:Phaeophyceae / Q000254:growth & development*; D000461:Rhodophyta / Q000254:growth & development*; D012623:Seawater / Q000382:microbiology; D013696:Temperature