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Atmospheric Transport and Deposition of Bromoanisoles Along a Temperate to Arctic Gradient.

https://arctichealth.org/en/permalink/ahliterature291852
Source
Environ Sci Technol. 2017 Oct 03; 51(19):10974-10982
Publication Type
Journal Article
Date
Oct-03-2017
Author
Terry F Bidleman
Eva Brorström-Lundén
Katarina Hansson
Hjalmar Laudon
Olle Nygren
Mats Tysklind
Author Affiliation
Department of Chemistry, Umeå University , SE-901 87 Umeå, Sweden.
Source
Environ Sci Technol. 2017 Oct 03; 51(19):10974-10982
Date
Oct-03-2017
Language
English
Publication Type
Journal Article
Keywords
Anisoles - analysis - chemistry
Arctic Regions
Baltic States
Environmental Monitoring - methods
Finland
Oceans and Seas
Rivers - chemistry
Sweden
Abstract
Bromoanisoles (BAs) arise from O-methylation of bromophenols, produced by marine algae and invertebrates. BAs undergo sea-air exchange and are transported over the oceans. Here we report 2,4-DiBA and 2,4,6-TriBA in air and deposition on the Swedish west coast (Råö) and the interior of arctic Finland (Pallas). Results are discussed in perspective with previous measurements in the northern Baltic region in 2011-2013. BAs in air decreased from south to north in the order Råö > northern Baltic > Pallas. Geometric mean concentrations at Pallas increased significantly (p
PubMed ID
28885011 View in PubMed
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Atmospheric Transport and Deposition of Bromoanisoles Along a Temperate to Arctic Gradient.

https://arctichealth.org/en/permalink/ahliterature285457
Source
Environ Sci Technol. 2017 Oct 03;51(19):10974-10982
Publication Type
Article
Date
Oct-03-2017
Author
Terry F Bidleman
Eva Brorström-Lundén
Katarina Hansson
Hjalmar Laudon
Olle Nygren
Mats Tysklind
Source
Environ Sci Technol. 2017 Oct 03;51(19):10974-10982
Date
Oct-03-2017
Language
English
Publication Type
Article
Abstract
Bromoanisoles (BAs) arise from O-methylation of bromophenols, produced by marine algae and invertebrates. BAs undergo sea-air exchange and are transported over the oceans. Here we report 2,4-DiBA and 2,4,6-TriBA in air and deposition on the Swedish west coast (Råö) and the interior of arctic Finland (Pallas). Results are discussed in perspective with previous measurements in the northern Baltic region in 2011-2013. BAs in air decreased from south to north in the order Råö > northern Baltic > Pallas. Geometric mean concentrations at Pallas increased significantly (p
PubMed ID
28885011 View in PubMed
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A carbon mass-balance budget for a periglacial catchment in West Greenland - Linking the terrestrial and aquatic systems.

https://arctichealth.org/en/permalink/ahliterature307790
Source
Sci Total Environ. 2020 Apr 01; 711:134561
Publication Type
Journal Article
Date
Apr-01-2020
Author
Tobias Lindborg
Johan Rydberg
Eva Andersson
Anders Löfgren
Emma Lindborg
Peter Saetre
Gustav Sohlenius
Sten Berglund
Ulrik Kautsky
Hjalmar Laudon
Author Affiliation
Swedish Nuclear Fuel and Waste Management Co. (SKB), Box 3091, SE-169 03 Solna, Sweden; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden.
Source
Sci Total Environ. 2020 Apr 01; 711:134561
Date
Apr-01-2020
Language
English
Publication Type
Journal Article
Abstract
Climate change is predicted to have far reaching consequences for the mobility of carbon in arctic landscapes. On a regional scale, carbon cycling is highly dependent on interactions between terrestrial and aquatic parts of a catchment. Despite this, studies that integrate the terrestrial and aquatic systems and study entire catchments using site-specific data are rare. In this work, we use data partly published by Lindborg et al. (2016a) to calculate a whole-catchment carbon mass-balance budget for a periglacial catchment in West Greenland. Our budget shows that terrestrial net primary production is the main input of carbon (99% of input), and that most carbon leaves the system through soil respiration (90% of total export/storage). The largest carbon pools are active layer soils (53% of total carbon stock or 13 kg C m-2), permafrost soils (30% of total carbon stock or 7.6 kg C m-2) and lake sediments (13% of total carbon stock or 10 kg C m-2). Hydrological transport of carbon from the terrestrial to aquatic system is lower than in wetter climates, but the annual input of 4100 kg C yr-1 (or 3.5 g C m-2 yr-1) that enters the lake via runoff is still three times larger than the eolian input of terrestrial carbon. Due to the dry conditions, the hydrological export of carbon from the catchment is limited (5% of aquatic export/storage or 0.1% of total export/storage). Instead, CO2 evasion from the lake surface and sediment burial accounts for 57% and 38% of aquatic export/storage, respectively (or 0.8% and 0.5% of total export/storage), and Two-Boat Lake acts as a net source of carbon to the atmosphere. The limited export of carbon to downstream water bodies make our study system different from wetter arctic environments, where hydrological transport is an important export pathway for carbon.
PubMed ID
31818588 View in PubMed
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Chlorinated pesticides and natural brominated anisoles in air at three northern Baltic stations.

https://arctichealth.org/en/permalink/ahliterature281092
Source
Environ Pollut. 2017 Mar 20;
Publication Type
Article
Date
Mar-20-2017
Author
Terry F Bidleman
Hjalmar Laudon
Olle Nygren
Staffan Svanberg
Mats Tysklind
Source
Environ Pollut. 2017 Mar 20;
Date
Mar-20-2017
Language
English
Publication Type
Article
Abstract
Polyurethane foam (PUF) disk passive samplers were deployed at one inland and two island locations in the Bothnian Bay region of the northern Baltic Sea. Uptake was linear over 81-147 d and a temperature range of -2.6 to 14.2 °C for organochlorine pesticides (OCPs) and current-use pesticides (CUPs) having log KOA =9 at ambient temperatures. Partial saturation of the PUF disks occurred for the more volatile OCPs hexachlorocyclohexanes (HCHs) and hexachlorobenzene (HCB), and for bromoanisoles (BAs), which are products of bromophenols released by natural and anthropogenic sources. Correction for nonlinear uptake of these was made using experimentally measured PUF-air partition coefficients. Passive-derived air concentrations of pesticides were uniform over the bay and agreed within a factor of 2 or better with levels determined by active (pumped) sampling at one of the island stations. Levels of OCPs were similar to those reported at background sites in the European and Canadian Arctic and at monitoring stations in the central Baltic and southern Scandinavia, indicating long-range transport. The insecticide chlorpyrifos was 10 times lower at bay stations than in the Canadian Arctic. Insight to sources and processes was gained by examining compound profiles. Fractions Falpha = a-HCH/(a-HCH + ?-HCH) and FTC = trans-chlordane/(trans-chlordane + cis-chlordane) at bay stations were higher than in the Norwegian and Finnish Arctic and similar to those at the southern monitoring stations. Volatilization of chlordanes from Baltic seawater may also modify FTC. Higher FTriBA = 2,4,6-TriBA/(2,4,6-TriBA + 2,4-DiBA) distinguished local volatilization from the Baltic Sea versus lower FTriBA found at the inland site and reported in air on the Norwegian coast, suggesting westerly transport from the Atlantic across Norway and Sweden.
PubMed ID
28336095 View in PubMed
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The concentrations and characteristics of dissolved organic matter in high-latitude lakes determine its ambient reducing capacity.

https://arctichealth.org/en/permalink/ahliterature308386
Source
Water Res. 2020 Feb 01; 169:115217
Publication Type
Journal Article
Date
Feb-01-2020
Author
Tao Jiang
Dingyong Wang
Bo Meng
Jinshu Chi
Hjalmar Laudon
Jiang Liu
Author Affiliation
State Cultivation Base of Eco-agriculture for Southwest Mountainous Land, Department of Environmental Sciences and Engineering, College of Resources and Environment, Southwest University, Chongqing, 400716, China; Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, SE-90183, Sweden. Electronic address: jiangtower666@163.com.
Source
Water Res. 2020 Feb 01; 169:115217
Date
Feb-01-2020
Language
English
Publication Type
Journal Article
Keywords
Carbon
Lakes
Mercury
Norway
Sweden
Abstract
The reducing capacity (RC) of natural organic matter plays an important role in the carbon cycle and biogeochemical fates of environmental contaminants in the aquatic system. However, the electron donation potentials of dissolved organic matter (DOM) from high-latitude lakes are still uncertain. In this study, we collected DOM samples from high-latitude lakes across the Arctic and boreal regions in Sweden and Norway to investigate the effects of the DOM concentration and characteristics on its ambient reducing capacity (ARC). Mercury (Hg(II)) abiotic reduction in darkness was used to determine the ARC. The results showed that the DOM in Arctic lakes is less terrestrial-dominant than in reference sites (i.e., forest lakes). Between the two categories of Arctic lakes, tundra lakes are more terrestrial-influenced compared to mountain lakes. Additionally, terrestrial-originated DOM is a main controlling factor for enhancing the ambient reducing capacity, whereas the DOM concentration, i.e., dissolved organic carbon (DOC), resulted in variations in the Hg/DOC ratios that also cause the variations of the observed ARC values. Thus, comparisons of the ARC values can be conducted while oxidant/DOC ratios are kept the same and reported through the method using heavy metals as a chemical probe. After correction for Hg/DOC ratio interference, the ambient reducing capacity of DOM followed the order: boreal forest lakes?>?Arctic tundra lakes?>?Arctic mountain lakes. This study highlights that the DOM concentration should also be considered when estimating the ARC as compared to the previous that mainly focusing on the properties of DOM such as its origins. As climate change is projected to be severe in high latitudes, this study demonstrates a significant connection between aquatic DOM geochemical reactivity and terrestrial inputs, which is crucial for a better prediction of the role of DOM in high-latitude lakes in the context of climate change.
PubMed ID
31675608 View in PubMed
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The fate of per- and polyfluoroalkyl substances within a melting snowpack of a boreal forest.

https://arctichealth.org/en/permalink/ahliterature257769
Source
Environ Pollut. 2014 Aug;191:190-8
Publication Type
Article
Date
Aug-2014
Author
Garry Codling
Crispin Halsall
Lutz Ahrens
Sabino Del Vento
Karin Wiberg
Magnus Bergknut
Hjalmar Laudon
Ralf Ebinghaus
Author Affiliation
Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK.
Source
Environ Pollut. 2014 Aug;191:190-8
Date
Aug-2014
Language
English
Publication Type
Article
Keywords
Alkanesulfonates - chemistry
Environmental Pollutants - analysis - chemistry
Fluorocarbons - analysis - chemistry
Freezing
Snow - chemistry
Sweden
Trees
Abstract
Per- and polyfluoroalkyl substances (PFAS) were measured systematically in a snowpack in northern Sweden to determine chemical behaviour during seasonal melt. Average PFAS concentrations were generally low, but displayed a wide range with median (range) concentrations of PFOA and PFOS of 66.5 pg L(-1) (ND-122) and 20.5 pg L(-1) (2.60-253) respectively. Average concentrations of the shorter chain, C4 and C5 perfluoroalkyl carboxylates (PFCAs) and perfluoroalkyl sulfonates (PFSAs), were ~10-fold higher. Differences in the PFAS concentrations and profile were observed between surface snow and deeper layers, with evidence of PFAS migration to deeper snow layers as melt progressed. Chemical loads (ng m(-2)) for C4-9 PFCAs decreased gradually as melt progressed, but increased for C4, C6-8 PFSAs and the longer chain C10-12 PFCAs. This enrichment in the diminishing snowpack is an unusual phenomenon that will affect PFAS elution with meltwater and subsequent entry to catchment surface waters.
PubMed ID
24852410 View in PubMed
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Forest streams are important sources for nitrous oxide emissions.

https://arctichealth.org/en/permalink/ahliterature309222
Source
Glob Chang Biol. 2020 02; 26(2):629-641
Publication Type
Journal Article
Date
02-2020
Author
Joachim Audet
David Bastviken
Mirco Bundschuh
Ishi Buffam
Alexander Feckler
Leif Klemedtsson
Hjalmar Laudon
Stefan Löfgren
Sivakiruthika Natchimuthu
Mats Öquist
Mike Peacock
Marcus B Wallin
Author Affiliation
Department of Bioscience, Aarhus University, Silkeborg, Denmark.
Source
Glob Chang Biol. 2020 02; 26(2):629-641
Date
02-2020
Language
English
Publication Type
Journal Article
Keywords
Fertilizers
Forests
Nitrous Oxide
Soil
Sweden
Abstract
Streams and river networks are increasingly recognized as significant sources for the greenhouse gas nitrous oxide (N2 O). N2 O is a transformation product of nitrogenous compounds in soil, sediment and water. Agricultural areas are considered a particular hotspot for emissions because of the large input of nitrogen (N) fertilizers applied on arable land. However, there is little information on N2 O emissions from forest streams although they constitute a major part of the total stream network globally. Here, we compiled N2 O concentration data from low-order streams (~1,000 observations from 172 stream sites) covering a large geographical gradient in Sweden from the temperate to the boreal zone and representing catchments with various degrees of agriculture and forest coverage. Our results showed that agricultural and forest streams had comparable N2 O concentrations of 1.6 ± 2.1 and 1.3 ± 1.8 µg N/L, respectively (mean ± SD) despite higher total N (TN) concentrations in agricultural streams (1,520 ± 1,640 vs. 780 ± 600 µg N/L). Although clear patterns linking N2 O concentrations and environmental variables were difficult to discern, the percent saturation of N2 O in the streams was positively correlated with stream concentration of TN and negatively correlated with pH. We speculate that the apparent contradiction between lower TN concentration but similar N2 O concentrations in forest streams than in agricultural streams is due to the low pH (
PubMed ID
31465582 View in PubMed
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Identifying and assessing the potential hydrological function of past artificial forest drainage.

https://arctichealth.org/en/permalink/ahliterature295742
Source
Ambio. 2018 Sep; 47(5):546-556
Publication Type
Journal Article
Date
Sep-2018
Author
Eliza Maher Hasselquist
William Lidberg
Ryan A Sponseller
Anneli Ågren
Hjalmar Laudon
Author Affiliation
Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Skogsmarksgränd, 901 83, Umeå, Sweden. eliza.hasselquist@gmail.com.
Source
Ambio. 2018 Sep; 47(5):546-556
Date
Sep-2018
Language
English
Publication Type
Journal Article
Keywords
Forests
Hydrology
Soil
Sweden
Wetlands
Abstract
Drainage of forested wetlands for increased timber production has profoundly altered the hydrology and water quality of their downstream waterways. Some ditches need network maintenance (DNM), but potential positive effects on tree productivity must be balanced against environmental impacts. Currently, no clear guidelines exist for DNM that strike this balance. Our study helps begin to prioritise DNM by: (1) quantifying ditches by soil type in the 68 km2 Krycklan Catchment Study in northern Sweden and (2) using upslope catchment area algorithms on new high-resolution digital elevation models to determine their likelihood to drain water. Ditches nearly doubled the size of the stream network (178-327 km) and 17% of ditches occurred on well-draining sedimentary soils, presumably making DNM unwarranted. Modelling results suggest that 25-50% of ditches may never support flow. With new laser scanning technology, simple mapping and modelling methods can locate ditches and model their function, facilitating efforts to balance DNM with environmental impacts.
Notes
Cites: Environ Sci Technol. 2011 Jan 15;45(2):354-9 PMID 21133421
Cites: J Anim Ecol. 2010 May;79(3):571-80 PMID 20180874
Cites: Sci Total Environ. 2001 Nov 12;279(1-3):117-29 PMID 11712589
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Cites: Ecology. 2015 Feb;96(2):381-91 PMID 26240860
PubMed ID
29098602 View in PubMed
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Land use influences macroinvertebrate community composition in boreal headwaters through altered stream conditions.

https://arctichealth.org/en/permalink/ahliterature281334
Source
Ambio. 2017 Apr;46(3):311-323
Publication Type
Article
Date
Apr-2017
Author
Micael Jonsson
Ryan M Burrows
Johan Lidman
Emma Fältström
Hjalmar Laudon
Ryan A Sponseller
Source
Ambio. 2017 Apr;46(3):311-323
Date
Apr-2017
Language
English
Publication Type
Article
Keywords
Animals
Biodiversity
Forests
Invertebrates
Rivers
Sweden
Abstract
Land use is known to alter the nature of land-water interactions, but the potential effects of widespread forest management on headwaters in boreal regions remain poorly understood. We evaluated the importance of catchment land use, land cover, and local stream variables for macroinvertebrate community and functional trait diversity in 18 boreal headwater streams. Variation in macroinvertebrate metrics was often best explained by in-stream variables, primarily water chemistry (e.g. pH). However, variation in stream variables was, in turn, significantly associated with catchment-scale forestry land use. More specifically, streams running through catchments that were dominated by young (11-50 years) forests had higher pH, greater organic matter standing stock, higher abundance of aquatic moss, and the highest macroinvertebrate diversity, compared to streams running through recently clear-cut and old forests. This indicates that catchment-scale forest management can modify in-stream habitat conditions with effects on stream macroinvertebrate communities and that characteristics of younger forests may promote conditions that benefit headwater biodiversity.
Notes
Cites: Ecology. 2009 May;90(5):1227-4119537544
Cites: Environ Manage. 2011 Jan;47(1):28-3921132293
Cites: Ambio. 2009 Nov;38(7):357-6319943391
Cites: Ambio. 2014 Mar;43(2):218-3324046144
Cites: Ambio. 2016 Feb;45 Suppl 2:188-20226744053
PubMed ID
27804095 View in PubMed
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Long-term declines in stream and river inorganic nitrogen (N) export correspond to forest change.

https://arctichealth.org/en/permalink/ahliterature273119
Source
Ecol Appl. 2016 Mar;26(2):545-56
Publication Type
Article
Date
Mar-2016
Author
Richard W Lucas
Ryan A Sponseller
Michael J Gundale
Johan Stendahl
Jonas Fridman
Peter Högberg
Hjalmar Laudon
Source
Ecol Appl. 2016 Mar;26(2):545-56
Date
Mar-2016
Language
English
Publication Type
Article
Abstract
Human activities have exerted a powerful influence on the biogeochemical cycles of nitrogen (N) and carbon (C) and drive changes that can be a challenge to predict given the influence of multiple environmental stressors. This study focused on understanding how land management and climate change have together influenced terrestrial N storage and watershed inorganic N export across boreal and sub-arctic landscapes in northern Sweden. Using long-term discharge and nutrient concentration data that have been collected continuously for over three decades, we calculated the hydrologic inorganic N export from nine watersheds in this region. We found a consistent decline in inorganic N export from 1985 to 2011 over the entire region from both small and large watersheds, despite the absence of any long-term trend in river discharge during this period. The steepest declines in inorganic N export were observed during the growing season, consistent with the hypothesis that observed changes are biologically mediated and are not the result of changes in long-term hydrology. Concurrent with the decrease in inorganic N export, we report sustained increases in terrestrial N accumulation in forest biomass and soils across northern Sweden. Given the close communication of nutrient and energy stores between plants, soils, and waters, our results indicate a regional tightening of the N cycle in an already N-limited environment as a result of changes in forest management and climate-mediated growth increases. Our results are consistent with declining inorganic N efflux previously reported from small headwater streams in other ecosystems and shed new light on the mechanisms controlling these patterns by identifying corresponding shifts in the terrestrial N balance, which have been altered by a combination of management activities and climate change.
PubMed ID
27209794 View in PubMed
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20 records – page 1 of 2.