Change search
ReferencesLink to record
Permanent link

Direct link
1000 years of environmental changes in Falun, Sweden: Lake Sediment as source material
Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
2012 (English)Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
Abstract [en]

The aim of this study was to get a better knowledge of the metal pollution and the mining

history of the Falun area. It adds new information on the geochemistry of the lakes and the

beginning of mining in the Falun region, together with the influence of early land use. The

main focus is on three lakes Hagtjärnen, Stugutjärnen and Nästjärnen, which were previously

dated and analyzed regarding acidification by Anna Ek. Additional supporting information is

provided from records from 10 other lakes, which are located at distances between 0-27 km

from the Falun Copper mine. Another specific focus is on the lake Tisken, which has been

assumed over the past 50 years to represent faithful historical record of mining in the Falun

area. In this study this lake record was dated and analyzed, too. The analyses of all the lakes

included resulted in four significant phases of environmental change, indicating the start of

agriculture and mining, the development of each sector, as well as the sharp increase in

pollution in the modern time period. Phase I covers the time period A.D. 700-1000 and

represents the time of the early beginning of land use and small scale mining activities. Phase

II represents the time between A.D. 1200 to 1450, which is dominated by an ongoing

development of mining and a sharp increase in metal concentrations and occurrence of

cultivated plants and plants favored by disturbance from A.D. 1450 onwards. The third phase,

representing the year A.D. 1540, clearly displays another period of sharp increases among the

metal concentrations, which coincides with a peak in Cu production volumes. Phase IV

covers the time period A.D. 1750-1900, referred to as Modern time, and features a clear

increase in Pb pollution, which is linked to the introduction of tetra ethyl Pb in the 1970s.

Other metals increase also, together with cultivated plants like cereals, indicating an ongoing

expansion of mining and agriculture. The results also indicate that Cu was not emitted as far

as other elements, like for example Pb, which led to great pollution only in the lakes close to

the Falun mine.

Another important finding is that the lake Tisken does not represent a continual historical

record, because the sediment is not a chronological sequence and instead likely represents

mostly a catastrophic input of debris of mixed age. The C-14 dating shows, that the sediment

is mixed and disturbed in Tisken. As a consequence, the long-standing interpretation of

Tisken’s sediment record as an archive for the historical start and late development of mining

at the Falun copper mine is incorrect

Place, publisher, year, edition, pages
Keyword [en]
Falun, Copper mine, Bergslagen, Tisken, sediment records
National Category
Other Earth and Related Environmental Sciences
URN: urn:nbn:se:umu:diva-61885OAI: diva2:572603
Subject / course
Examensarbete i Geovetenskap/naturgeografi avseende masterexamen
Educational program
Master's Programme in Geoecology
Life Earth Science
Available from: 2012-11-28 Created: 2012-11-28 Last updated: 2012-11-28Bibliographically approved

Open Access in DiVA

fulltext(6126 kB)332 downloads
File information
File name FULLTEXT01.pdfFile size 6126 kBChecksum SHA-512
Type fulltextMimetype application/pdf

By organisation
Department of Ecology and Environmental Sciences
Other Earth and Related Environmental Sciences

Search outside of DiVA

GoogleGoogle Scholar
Total: 332 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 90 hits
ReferencesLink to record
Permanent link

Direct link