The University of Southampton
University of Southampton Institutional Repository

A multi proxy analysis of climate impacts on the recent development of subarctic lake Saanajärvi in Finnish Lapland

A multi proxy analysis of climate impacts on the recent development of subarctic lake Saanajärvi in Finnish Lapland
A multi proxy analysis of climate impacts on the recent development of subarctic lake Saanajärvi in Finnish Lapland
Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern Finnish Lapland are studied by comparison of various biological and sedimentological proxies with the 200-year long climate record, specifically reconstructed for the site using a data-set of European-wide meteorological data. The multi-proxy evidence of simultaneously changing diatom, Cladocera, and chrysophyte assemblages along with the increased rates of organic matter accumulation and pigment concentrations suggest that the lake has undergone a distinct typological change starting from the turn of the 20th century. This change, indicating an increase in lake productivity, parallels a pronounced rise in the meteorologically reconstructed mean annual and summer temperatures in the region between ca. 1850 and 1930's. We postulate that, during the Little Ice Age, the lake was not, or was only weakly, thermally stratified during summer, whereas the subsequent increase in air and hence epilimnetic water temperatures resulted in the development of the present summer stratification. The increased thermal stability of the lake created more suitable conditions for the growth of phyto- and zooplankton and changed the overall primary production from benthos to plankton. Mineral magnetic and carbonaceous particle records suggest long-distance pollution, particularly since the 1920's, yet the observed changes in lake biota and productivity can hardly be explained by this very minor background pollution; the 20th century species configurations are typical of neutral waters and do not indicate any response to pollution.
Finnish Lapland, subarctic lake, climate change, lake sediments, diatoms, Cladocera, chrysophytes, magnetism, carbonaceous particles, plant pigments
0921-2728
59-77
Korhola, A.
b61b5619-689c-413d-8d55-4f07fe421337
Sorvari, S.
ea7b5f93-cded-4625-bd46-dd424e1e2aee
Rautio, M.
2f2e724e-ddd0-4521-aace-9e049bf86ede
Appleby, P.G.
e83ef8a2-bf52-4999-a9fb-bc47e996b2e5
Dearing, J.A.
dff37300-b8a6-4406-ad84-89aa01de03d7
Hu, Y.
64fd97b0-7ac6-458b-8e89-5ddc6b49c448
Rose, N.
a917d928-e483-49f5-b6d6-96201b283c9a
Lami, A.
37288a59-0da9-4915-83a2-852cfcd834fe
Cameron, N.G.
fb156ed4-110f-4d79-bf94-ba421e354f8e
Korhola, A.
b61b5619-689c-413d-8d55-4f07fe421337
Sorvari, S.
ea7b5f93-cded-4625-bd46-dd424e1e2aee
Rautio, M.
2f2e724e-ddd0-4521-aace-9e049bf86ede
Appleby, P.G.
e83ef8a2-bf52-4999-a9fb-bc47e996b2e5
Dearing, J.A.
dff37300-b8a6-4406-ad84-89aa01de03d7
Hu, Y.
64fd97b0-7ac6-458b-8e89-5ddc6b49c448
Rose, N.
a917d928-e483-49f5-b6d6-96201b283c9a
Lami, A.
37288a59-0da9-4915-83a2-852cfcd834fe
Cameron, N.G.
fb156ed4-110f-4d79-bf94-ba421e354f8e

Korhola, A., Sorvari, S., Rautio, M., Appleby, P.G., Dearing, J.A., Hu, Y., Rose, N., Lami, A. and Cameron, N.G. (2002) A multi proxy analysis of climate impacts on the recent development of subarctic lake Saanajärvi in Finnish Lapland. Journal of Paleolimnology, 28 (1), 59-77. (doi:10.1023/A:1020371902214).

Record type: Article

Abstract

Responses to recent climatic changes in the sediment of subarctic Lake Saanajärvi in northwestern Finnish Lapland are studied by comparison of various biological and sedimentological proxies with the 200-year long climate record, specifically reconstructed for the site using a data-set of European-wide meteorological data. The multi-proxy evidence of simultaneously changing diatom, Cladocera, and chrysophyte assemblages along with the increased rates of organic matter accumulation and pigment concentrations suggest that the lake has undergone a distinct typological change starting from the turn of the 20th century. This change, indicating an increase in lake productivity, parallels a pronounced rise in the meteorologically reconstructed mean annual and summer temperatures in the region between ca. 1850 and 1930's. We postulate that, during the Little Ice Age, the lake was not, or was only weakly, thermally stratified during summer, whereas the subsequent increase in air and hence epilimnetic water temperatures resulted in the development of the present summer stratification. The increased thermal stability of the lake created more suitable conditions for the growth of phyto- and zooplankton and changed the overall primary production from benthos to plankton. Mineral magnetic and carbonaceous particle records suggest long-distance pollution, particularly since the 1920's, yet the observed changes in lake biota and productivity can hardly be explained by this very minor background pollution; the 20th century species configurations are typical of neutral waters and do not indicate any response to pollution.

This record has no associated files available for download.

More information

Published date: 1 June 2002
Keywords: Finnish Lapland, subarctic lake, climate change, lake sediments, diatoms, Cladocera, chrysophytes, magnetism, carbonaceous particles, plant pigments

Identifiers

Local EPrints ID: 55645
URI: http://eprints.soton.ac.uk/id/eprint/55645
ISSN: 0921-2728
PURE UUID: e7336cc2-6c2f-420d-8a48-945aeef99114
ORCID for J.A. Dearing: ORCID iD orcid.org/0000-0002-1466-9640

Catalogue record

Date deposited: 04 Aug 2008
Last modified: 16 Mar 2024 03:38

Export record

Altmetrics

Contributors

Author: A. Korhola
Author: S. Sorvari
Author: M. Rautio
Author: P.G. Appleby
Author: J.A. Dearing ORCID iD
Author: Y. Hu
Author: N. Rose
Author: A. Lami
Author: N.G. Cameron

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×