transparent gif


Ej inloggad.

Göteborgs universitets publikationer

The Holocene-Anthropocene transition in lakes of western Spitsbergen, Svalbard (Norwegian High Arctic): climate change and nitrogen deposition

Författare och institution:
Sofia Holmgren (Institutionen för geovetenskaper); Christian Bigler (-); Olafur Ingolfsson (-); Alexander P. Wolfe (-)
Publicerad i:
JOURNAL OF PALEOLIMNOLOGY, 43 ( 2 ) s. 393-412
Artikel, refereegranskad vetenskaplig
Sammanfattning (abstract):
Lake sediments from four small lakes on western Spitsbergen (Svalbard Archipelago, Norwegian High Arctic) preserve biostratigraphic and isotopic evidence for a complex suite of twentieth century environmental changes. At Lake Skardtjørna and Lake Tjørnskardet on Nordenskio¨ldkysten, there is a marked diatom floristic change coupled to increased diatom concentrations beginning around 1920. At Lake Istjørna and Lake Istjørnelva, 25 km southwest of Longyearbyen, both diatom total valve and chrysophyte stomatocyst concentrations have increased dramatically since the beginning of the 1900s. The early twentieth century changes are probably related to climate warming after the Little Ice Age. However, the most pronounced changes in diatom assemblages seem to have occurred in the last few decades. At the same time, nitrogen stable isotopes in sediment organic matter in two of the lakes became progressively depleted by*2%, which is consistent with diffuse atmospheric inputs from anthropogenic sources and attendant fertilization. These data suggest that climate change and nitrogen deposition may be acting together in driving these lakes towards new ecological states that are unique in the context of the Holocene.
Ämne (baseras på Högskoleverkets indelning av forskningsämnen):
Geovetenskap och miljövetenskap
sedimentary organic-matter, canonical correspondence-analysis, recent environmental-change, ice-core, anthropogenic sulfate, nitrate utilization, diatom analysis, alpine lakes, record, trends
Postens nummer:
Posten skapad:
2011-05-03 09:38
Posten ändrad:
2011-11-29 15:01

Visa i Endnote-format

Göteborgs universitet • Tel. 031-786 0000
© Göteborgs universitet 2007