Circumpolar synchrony in big river bacterioplankton.
Natural bacterial communities are extremely diverse and highly dynamic, but evidence is mounting that the compositions of these communities follow predictable temporal patterns. We investigated these patterns with a 3-year, circumpolar study of bacterioplankton communities in the six largest rivers of the pan-arctic watershed (Ob', Yenisey, Lena, Kolyma, Yukon, and Mackenzie), five of which are among Earth's 25 largest rivers. Communities in the six rivers shifted synchronously over time, correlating with seasonal shifts in hydrology and biogeochemistry and clustering into three groups: winter/spring, spring freshet, and summer/fall. This synchrony indicates that hemisphere-scale variation in seasonal climate sets the pace of variation in microbial diversity. Moreover, these seasonal communities reassembled each year in all six rivers, suggesting a long-term, predictable succession in the composition of big river bacterioplankton communities.
Crump
Byron C
BC
Horn Point Laboratory, University of Maryland Center for Environmental Science, Cambridge, MD 21613, USA.
Peterson
Bruce J
BJ
Raymond
Peter A
PA
Amon
Rainer M W
RM
Rinehart
Amanda
A
McClelland
James W
JW
Holmes
Robert M
RM
D001110:Arctic Regions; D001419:Bacteria / Q000254:growth & development / Q000302:isolation & purification; D001483:Base Sequence; D044822:Biodiversity; D004463:Ecology; D008969:Molecular Sequence Data; D010933:Plankton / Q000254:growth & development / Q000302:isolation & purification; D011157:Population Dynamics; D045483:Rivers / Q000382:microbiology*; D012621:Seasons; D013997:Time Factors