Organic lacustrine sediment varves as indicators of past precipitation changes: a 3,000-year climate record from Central Finland
Saarni, S., Saarinen, T., & Lensu, A. (2015). Organic lacustrine sediment varves as indicators of past precipitation changes: a 3,000-year climate record from Central Finland. Journal of Paleolimnology, 53 (4), 401-413. doi:10.1007/s10933-015-9832-8
Published inJournal of Paleolimnology
DisciplineYmpäristötiede ja -teknologia
© Springer Science+Business Media Dordrecht 2015. This is a final draft version of an article whose final and definitive form has been published by Springer. Published in this repository with the kind permission of the publisher.
Annually laminated (varved) sediments from Lake Kallio-Kourujärvi, Central Finland, provide high-resolution sedimentological data for the last three millennia. These varves consist of two laminae that represent (1) deposition during the spring-to-autumn growing season, composed of degraded organic matter and a variety of microfossils, and (2) deposition during winter, composed of fine-grained homogenous organic matter. Because of the absence of a clastic lamina, these varves differ from the typical, well-described, clastic-organic varve sequences in Fennoscandian lakes. Such organic varves in Finnish lakes have not been studied in detail before. Three thousand varves were counted and their seasonal deposition was distinguished. Comparison of varve thickness with meteorological data revealed a positive correlation between organic varve thickness and precipitation. This suggests that catchment erosion processes and consequent organic matter and nutrient inputs are important factors in organic varve formation. The correlation between temperature and growing-season lamina thickness varied from insignificant, to positive, to negative during different time spans. This suggests that organic matter accumulation can sometimes have a significant, but unpredictable role in organic varve formation, via organic matter production and degradation, processes that are influenced strongly by water column temperature. The organic varves of Lake Kallio-Kourujärvi enable a unique, high-resolution approach for the study of past climate and environment. Our results suggest that decadal periods of increased precipitation occurred during BP 2150–2090, 1710–1620, 1410–1360, 920–870 (1030–1080 AD), and after 370 BP (1580 AD). Dryer intervals occurred during BP 2750–2720, 1900–1850, 1800–1740, 1600–1500, and 780–700 (1170–1250 AD), 590–520 (1360–1430 AD). ...
MetadataShow full item record
Showing items with similar title or keywords.
A Parody of the Church Service in Seventeenth-Century Finland. Reconstructing Popular Religion on the Basis of Court Records Kuha, Miia (Institut für die Erforschung der Frühen Neuzeit, 2012)
Aquatic effects of peat extraction and peatland forest drainage : a comparative sediment study of two adjacent lakes in Central Finland Kauppila, T.; Ahokas, T.; Nikolajev-Wikström, L.; Mäkinen, J.; Tammelin, M. H.; Meriläinen, Jarmo J. (Springer, 2016)The aquatic effects of forestry practices and peat extraction continue to cause serious concerns. The effect mechanisms of peat extraction on water quality and aquatic ecology of the receiving surface waters are well known, ...
Rasmus, Sirpa; Kivinen, Sonja; Irannezhad, Masoud (Institute of Physics Publishing Ltd., 2018)Basal ice formation in the terrestrial snow cover is a common phenomenon in northern circumpolar areas, one having significant impacts on ecosystems, vegetation, animals and human activities. There is limited knowledge ...
The stable isotope composition of organic and inorganic fossils in lake sediment records : Current understanding, challenges, and future directions van Hardenbroek, M.; Chakraborty, A.; Davies, K. L.; Harding, P.; Heiri, O.; Henderson, A. C. G.; Holmes, J. A.; Lasher, G. E.; Leng, M. J.; Panizzo, V. N.; Roberts, L.; Schilder, Johannes; Trueman, C. N.; Wooller, M. J. (Elsevier Ltd., 2018)This paper provides an overview of stable isotope analysis (H, C, N, O, Si) of the macro- and microscopic remains from aquatic organisms found in lake sediment records and their application in (palaeo)environmental science. ...
Life beyond the camp : rethinking return, reconstruction and women's expression of lived experiences in Northern Uganda Frérotte, Naomi (2015)The conflict in Northern Uganda is recognized as having come to an end with the signing of a cessation of hostilities agreement between the Lord’s Resistance Army and the Government of Uganda in August 2006, which resulted ...