Home About Browse Search
Svenska


Hagblom, Robin, 2017. Catchment influences on mercury methylation in a peatland chronosequence. Second cycle, A2E. Uppsala: SLU, Dept. of Aquatic Sciences and Assessment

[img]
Preview
PDF
2MB

Abstract

Since the beginning of industrialization, emissions of mercury (Hg) from human activities in excess of natural levels have increased depo-sition rates to ecosystems, storage in soils and loading to aquatic envi-ronments. Toxicity to animals, subject to this accumulation, as well as to humans consuming them, are the major concerns driving research on this subject. Peatlands play a key role in Hg cycling as hotspots for Hg methylation, methyl mercury (MeHg) being a particularly mobile, bioavailable form of Hg that is prone to bioaccumulation. Underlying geography is fundamental in shaping the hydrology of a given area and, therefore, the locations of points of accumulation and methylation of Hg.

In this study, potential relationships between geographic parame-ters, elucidated via GIS analysis were investigated with the aim of iden-tifying which parameters were relevant as explanatory variables in the prediction of Hg concentrations in the study area. Elevation was ex-pected to strongly predict MeHg concentrations due to the presence of a local chronosequence, created by land rise. The land’s age since emergence from the sea ranges from years to thousands of years within a span of 10 km, enabled this investigation in an environment in which climate is controlled for.

With 13 of the 15 watershed areas less than 1 ha and 9 less than 500m2, little of meaning could be concluded from statistical analysis with certainty. Linear regression and PLS pointed to Elevation’s rela-tionship with THg, PLS implicated Watershed Area as being associated with MeHg, and PCA hinted at the relevance of Area as well as a clus-ter of Slope, Downslope Index, Curvature, and % Forest for sample sites with extreme values of Hg and other metals. Our results indicate that elevation alone is not a strong predictor of MeHg concentration along this peatland chronosequence.

Main title:Catchment influences on mercury methylation in a peatland chronosequence
Authors:Hagblom, Robin
Supervisor:Wang, Baolin
Examiner:Berggren Kleja, Dan
Series:UNSPECIFIED
Volume/Sequential designation:UNSPECIFIED
Year of Publication:2017
Level and depth descriptor:Second cycle, A2E
Student's programme affiliation:None
Supervising department:(NL, NJ) > Dept. of Aquatic Sciences and Assessment
Keywords:methyl mercury, GIS, northern peatland, mire, watershed, elevation
URN:NBN:urn:nbn:se:slu:epsilon-s-9445
Permanent URL:
http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-s-9445
Subjects:Soil science and management
Language:English
Deposited On:29 Jun 2018 10:35
Metadata Last Modified:29 Jun 2018 10:35

Repository Staff Only: item control page

Downloads

Downloads per year (since September 2012)

View more statistics

Downloads
Hits