Eklöf, Karin
(2012).
Effects of stump harvesting and site preparation on mercury mobilization and methylation.
Diss. (sammanfattning/summary)
Uppsala :
Sveriges lantbruksuniv.,
Acta Universitatis Agriculturae Sueciae, 1652-6880
; 2012:76
ISBN 978-91-576-7723-5
[Doctoral thesis]
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PDF
1MB |
Abstract
Mercury (Hg) is an element of major concern in boreal freshwater ecosystems, due to high concentrations of Hg in fish. Forestry operations have been reported to increase the concentrations and loads of Hg to surface waters. In this thesis a series of catchment-scale experiments were used to determine forestry effects on total mercury (THg) and methyl mercury (MeHg) runoff concentrations caused by stump harvest, site preparation and antecedent logging.
The stump harvest did not increase Hg concentrations in runoff relative to traditional site preparation in either of the stump harvest studies. The lack of treatment effects caused by stump harvest and site preparation in one of the stump harvest studies focused attention on the antecedent logging. The question of whether the logging was of major importance when compared with the subsequent soil disturbance caused by site preparation was further investigated in the Balsjö catchment study. Contrary to the stump harvest study, the concentrations of THg and MeHg increased after both logging and site preparation by around 30-40 %, but no significant effect was detected after logging only. The more pronounced effect of site preparation in the Balsjö study might be due to more soil disturbance caused by site preparation that was carried out in early summer compared with the logging that was carried out in winter when snow protected the ground. The season and weather conditions present during forestry operations might therefore be of importance when considering possible treatment effects on Hg. The variation in forestry effects on Hg between catchments in this thesis, as well as in earlier studies, indicates that the catchment sensitivity to forestry operations varies. This variation could be due to differences in the biogeochemical status of soils and waters. It is thus vital to determine what factors influence THg and MeHg concentrations in different catchments. The importance of total organic carbon (TOC) was highlighted by a strong correlation between THg and TOC both within and between the study catchments in this thesis. The discharge was also found to have a positive influence on the THg and TOC concentrations, while temperature had a positive influence on the MeHg concentrations.
This thesis suggests that when and how forestry operations are implemented might be more important than the treatment type in some catchments. This thesis also identifies a variation in catchment sensitivity to forestry operations that requires further investigation.
| Authors/Creators: | Eklöf, Karin | ||||||||||
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| Title: | Effects of stump harvesting and site preparation on mercury mobilization and methylation | ||||||||||
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| Series/Journal: | Acta Universitatis Agriculturae Sueciae (1652-6880) | ||||||||||
| Year of publishing : | September 2012 | ||||||||||
| Volume: | 2012:76 | ||||||||||
| Number of Pages: | 57 | ||||||||||
| Papers/manuscripts: |
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| Place of Publication: | Uppsala | ||||||||||
| Publisher: | Inst. för vatten och miljö, Sveriges lantbruksuniversitet | ||||||||||
| Associated Programs and Other Stakeholders: | SLU - Environmental assessment > Data from Environmental Assesment (FoMA) is used SLU - Environmental assessment > Programme Forest SLU - Environmental assessment > Programme Lakes and watercourses SLU - Environmental assessment > Programme Non-Toxic Environment | ||||||||||
| ISBN for printed version: | 978-91-576-7723-5 | ||||||||||
| ISSN: | 1652-6880 | ||||||||||
| Language: | English | ||||||||||
| Publication Type: | Doctoral thesis | ||||||||||
| Full Text Status: | Public | ||||||||||
| Agris subject categories.: | K Forestry > K10 Forestry production P Natural resources > P01 Nature conservation and land resources T Pollution > T01 Pollution | ||||||||||
| Subjects: | (A) Swedish standard research categories 2011 > 1 Natural sciences > 105 Earth and Related Environmental Sciences > Geochemistry | ||||||||||
| Agrovoc terms: | surface water, boreal forests, mercury, methylation, stumps, stump removal, forestry operations, site preparation, leaching, runoff water, water pollution, sweden | ||||||||||
| Keywords: | Forestry, Treatment effects, Boreal streams, Catchments, Methylation, Discharge, Organic carbon | ||||||||||
| URN:NBN: | urn:nbn:se:slu:epsilon-e-637 | ||||||||||
| Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-e-637 | ||||||||||
| ID Code: | 9104 | ||||||||||
| Department: | (NL, NJ) > Dept. of Aquatic Sciences and Assessment | ||||||||||
| External funders: | Swedish Energy Agency and FORMAS and Future Forests and Holmen and MISTRA and Swedish Environmental Protection Agency and Svenska cellulosa AB and Skogssällskapet and Sveaskog | ||||||||||
| Deposited By: | Karin Eklöf | ||||||||||
| Deposited On: | 02 Oct 2012 08:59 | ||||||||||
| Metadata Last Modified: | 09 Nov 2017 12:17 |
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