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Barnas AF, Ladle A, Burgar JM, Burton AC, Boyce MS, Eliuk L, Grey F, Heim N, Paczkowski J, Stewart FEC, Tattersall E, Fisher JT. How landscape traits affect boreal mammal responses to anthropogenic disturbance. Sci Total Environ 2024; 915:169285. [PMID: 38103612 DOI: 10.1016/j.scitotenv.2023.169285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2023] [Revised: 12/04/2023] [Accepted: 12/09/2023] [Indexed: 12/19/2023]
Abstract
Understanding mammalian responses to anthropogenic disturbance is challenging, as ecological processes and the patterns arising therefrom notoriously change across spatial and temporal scales, and among different landscape contexts. Responses to local scale disturbances are likely influenced by landscape context (e.g., overall landscape-level disturbance, landscape-level productivity). Hierarchical approaches considering small-scale sampling sites as nested holons within larger-scale landscapes, which constrain processes in lower-level holons, can potentially explain differences in ecological processes between multiple locations. We tested hypotheses about mammal responses to disturbance and interactions among holons using collected images from 957 camera sites across 9 landscapes in Alberta from 2007 to 2020 and examined occurrence for 11 mammal species using generalized linear mixed models. White-tailed deer occurred more in higher disturbed sites within lower disturbed landscapes (β = -0.30 [-0.4 to -0.15]), whereas occurrence was greater in highly disturbed sites within highly disturbed landscapes for moose (β = 0.20 [0.09-0.31]), coyote (β = 0.20 [0.08-0.26]), and lynx (β = 0.20 [0.07-0.26]). High disturbance sites in high productivity landscapes had higher occurrence of black bears (β = -0.20 [-0.46 to -0.01]), lynx (β = -0.70 [-0.97 to -0.34]), and wolves (β = -0.50 [-0.73 to -0.21]). Conversely, we found higher probability of occurrence in low productivity landscapes with increasing site disturbance for mule deer (β = 0.80 [0.39-1.14]), and white-tailed deer (β = 0.20 [0.01-0.47]). We found the ecological context created by aggregate sums (high overall landscape disturbance), and by subcontinental hydrogeological processes in which that landscape is embedded (high landscape productivity), alter mammalian responses to anthropogenic disturbance at local scales. These responses also vary by species, which has implications for large-scale conservation planning. Management interventions must consider large-scale geoclimatic processes and geographic location of a landscape when assessing wildlife responses to disturbance.
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Affiliation(s)
- Andrew F Barnas
- School of Environmental Studies, University of Victoria, Victoria, Canada.
| | - Andrew Ladle
- School of Environmental Studies, University of Victoria, Victoria, Canada; Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Joanna M Burgar
- School of Environmental Studies, University of Victoria, Victoria, Canada; Department of Forest Resources Management, University of British Columbia, Vancouver, Canada
| | - A Cole Burton
- Department of Forest Resources Management, University of British Columbia, Vancouver, Canada; Biodiversity Research Centre, University of British Columbia, Vancouver, Canada
| | - Mark S Boyce
- Department of Biological Sciences, University of Alberta, Edmonton, Canada
| | - Laura Eliuk
- School of Environmental Studies, University of Victoria, Victoria, Canada
| | - Fabian Grey
- Whitefish Lake First Nation #459, Atikameg, Alberta, Canada
| | - Nicole Heim
- School of Environmental Studies, University of Victoria, Victoria, Canada
| | - John Paczkowski
- Government of Alberta, Forests, Parks, and Tourism, Canmore, Alberta, Canada
| | - Frances E C Stewart
- School of Environmental Studies, University of Victoria, Victoria, Canada; Department of Biology, Wilfrid Laurier University, Waterloo, Ontario (Haldimand Tract), Canada
| | - Erin Tattersall
- Department of Forest Resources Management, University of British Columbia, Vancouver, Canada
| | - Jason T Fisher
- School of Environmental Studies, University of Victoria, Victoria, Canada
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Roy P, Rutter A, Gainer A, Haack E, Zeeb BA. Phytotoxicity of weathered petroleum hydrocarbons in soil to boreal plant species. Environ Res 2023; 238:117136. [PMID: 37717802 DOI: 10.1016/j.envres.2023.117136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2023] [Revised: 08/25/2023] [Accepted: 09/12/2023] [Indexed: 09/19/2023]
Abstract
Canada has extensive petroleum hydrocarbon (PHC) contamination in northern areas and the boreal forest region from historical oil and gas activities. Since the 2013 standardization of boreal forest species for plant toxicity testing in Canada, there has been a need to build the primary literature of the toxicity of weathered PHCs to these species. A series of toxicity experiments were carried out using fine-grained (<0.005-0.425 mm) background (100 total mg/kg total PHCs) and weathered contaminated soil (11,900 mg/kg total PHCs) collected from a contaminated site in northern Ontario, Canada. The PHC mixture in the contaminated site soil was characterized through Canadian Council of Ministers of the Environment Fractions, as indicated by the number equivalent normal straight-chain hydrocarbons (nC). The soil was highly contaminated with Fraction 2 (>nC10 to nC16) at 4790 mg/kg and Fraction 3 (>nC16 to nC34) at 4960 mg/kg. Five plant species (Elymus trachycaulus, Achillea millefolium, Picea mariana, Salix bebbiana, and Alnus viridis) were grown from seed in 0%, 25%, 50%, 75%, and 100% relative contamination mixtures of the PHC-contaminated and background soil from the site over 2-6 weeks. All five species showed significant inhibition in shoot length, shoot weight, root length, and/or root weight (Kruskal-Wallis Tests: p < 0.05, df = 4.0). Measurements of 25% inhibitory concentrations (IC25) following PHC toxicity experiments revealed that S. bebbiana was most significantly impaired by the PHC-contaminated soil (410-990 mg/kg total PHCs), where it showed <35% germination. This study indicates that natural weathering of Fraction 2- and Fraction 3-concentrated soil did not eliminate phytotoxicity to boreal plant species. Furthermore, it builds on the limited existing literature for toxicity of PHCs on boreal plants and supports site remediation to existing Canadian provincial PHC guidelines.
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Affiliation(s)
- Prama Roy
- School of Environmental Studies, Queen's University, Kingston, ON, K7L 3N6, Canada.
| | - Allison Rutter
- School of Environmental Studies, Queen's University, Kingston, ON, K7L 3N6, Canada.
| | - Amy Gainer
- Clear-Site Solutions (formerly with Advisian/Worley Canada Services), 9807 83 Ave Edmonton, AB, Canada.
| | - Elizabeth Haack
- Ecometrix Incorporated, 6800 Campobello Road, Mississauga, ON, L5N 2L8, Canada.
| | - Barbara A Zeeb
- Department of Chemistry and Chemical Engineering, Royal Military College of Canada, Kingston, ON, K7K 7B4, Canada.
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Choi WJ, Park HJ, Baek N, In Yang H, Kwak JH, Lee SI, Park SW, Shin ES, Lim SS. Patterns of δ 15N in forest soils and tree foliage and rings between climate zones in relation to atmospheric nitrogen deposition: A review. Sci Total Environ 2023; 900:165866. [PMID: 37516182 DOI: 10.1016/j.scitotenv.2023.165866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 07/25/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
The stable nitrogen (N) isotope ratio (δ15N) of forest samples (soils, tree foliage, and tree rings) has been used as a powerful indicator to explore the responses of forest N cycling to atmospheric N deposition. This review investigated the patterns of δ15N in forest samples between climate zones in relation to N deposition. Forest samples exhibited distinctive δ15N patterns between climate zones due to differences in site conditions (i.e., N availability and retention capacity) and the atmospheric N deposition characteristics (i.e., N deposition rate, N species, and δ15N of deposited N). For example, the δ15N of soil and foliage was higher for tropical forests than for other forests by >1.2 ‰ and 4 ‰, respectively due to the site conditions favoring N losses coupled with relatively low N deposition for tropical forests. This was further supported by the unchanged or increased δ15N of tree rings in tropical forests, which contrasts with other climate zones that exhibited a decreased wood δ15N since the 1920s. Subtropical forests under a high deposition of reduced N (NHy) had a lower δ15N by 2-5 ‰ in the organic layer compared with the other forests, reflecting high retention of 15N-depleted NHy deposition. At severely polluted sites in East Asia, the decreased δ15N in wood also reflected the consistent deposition of 15N-depleted NHy. Though our data analysis represents only a subset of global forest sites where atmospheric N deposition is of interest, the results suggest that the direction and magnitude of the changes in the δ15N of forest samples are related to both atmospheric N and site conditions particularly for tropical vs. subtropical forests. Site-specific information on the atmospheric N deposition characteristics would allow more accurate assessment of the variations in the δ15N of forest samples in relation to N deposition.
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Affiliation(s)
- Woo-Jung Choi
- Department of Rural & Biosystems Engineering (Brain Korea 21), Chonnam National University, Gwangju 61186, Republic of Korea; AgriBio Institute of Climate Change Management, Chonnam National University, Gwangju 61186, Republic of Korea.
| | - Hyun-Jin Park
- Crop Production & Physiology Division, National Institute of Crop Science, Rural Development Administration, Wanju, Jeollabukdo 55365, Republic of Korea
| | - Nuri Baek
- Department of Rural & Biosystems Engineering (Brain Korea 21), Chonnam National University, Gwangju 61186, Republic of Korea
| | - Hye In Yang
- Max Planck Institute for Biogeochemistry, Jena 07745, Germany
| | - Jin-Hyeob Kwak
- Department of Rural Construction Engineering, Jeonbuk National University, Jeonju, Jeollabukdo 57896, Republic of Korea
| | - Sun-Il Lee
- Climate Change Assessment Division, National Institute of Agricultural Science, Rural Development Administration, Wanju, Jeollabukdo 55365, Republic of Korea
| | - Seo-Woo Park
- Department of Rural & Biosystems Engineering (Brain Korea 21), Chonnam National University, Gwangju 61186, Republic of Korea
| | - Eun-Seo Shin
- Department of Rural & Biosystems Engineering (Brain Korea 21), Chonnam National University, Gwangju 61186, Republic of Korea
| | - Sang-Sun Lim
- Bio R&D Center, CJ Cheiljedang, Suwon, Gyeonggi-do 16495, Republic of Korea
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Fuchs B, Joly K, Hilderbrand GV, Evans AL, Rodushkin I, Mangipane LS, Mangipane BA, Gustine DD, Zedrosser A, Brown L, Arnemo JM. Toxic elements in arctic and sub-arctic brown bears: Blood concentrations of As, Cd, Hg and Pb in relation to diet, age, and human footprint. Environ Res 2023; 229:115952. [PMID: 37116674 DOI: 10.1016/j.envres.2023.115952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 04/16/2023] [Accepted: 04/18/2023] [Indexed: 05/07/2023]
Abstract
Contamination with arsenic (As), cadmium (Cd), mercury (Hg) and lead (Pb) is a global concern impairing resilience of organisms and ecosystems. Proximity to emission sources increases exposure risk but remoteness does not alleviate it. These toxic elements are transported in atmospheric and oceanic pathways and accumulate in organisms. Mercury accumulates in higher trophic levels. Brown bears (Ursus arctos), which often live in remote areas, are long-lived omnivores, feeding on salmon (Oncorhynchus spp.) and berries (Vaccinium spp.), resources also consumed by humans. We measured blood concentrations of As, Cd, Hg and Pb in bears (n = 72) four years and older in Scandinavia and three national parks in Alaska, USA (Lake Clark, Katmai and Gates of the Arctic) using high-resolution, inductively-coupled plasma sector field mass spectrometry. Age and sex of the bears, as well as the typical population level diet was associated with blood element concentrations using generalized linear regression models. Alaskan bears consuming salmon had higher Hg blood concentrations compared to Scandinavian bears feeding on berries, ants (Formica spp.) and moose (Alces). Cadmium and Pb blood concentrations were higher in Scandinavian bears than in Alaskan bears. Bears using marine food sources, in addition to salmon in Katmai, had higher As blood concentrations than bears in Scandinavia. Blood concentrations of Cd and Pb, as well as for As in female bears increased with age. Arsenic in males and Hg concentrations decreased with age. We detected elevated levels of toxic elements in bears from landscapes that are among the most pristine on the planet. Sources are unknown but anthropogenic emissions are most likely involved. All study areas face upcoming change: Increasing tourism and mining in Alaska and more intensive forestry in Scandinavia, combined with global climate change in both regions. Baseline contaminant concentrations as presented here are important knowledge in our changing world.
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Affiliation(s)
- Boris Fuchs
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway.
| | - Kyle Joly
- National Park Service, Gates of the Arctic National Park and Preserve, 99709, Fairbanks, Alaska, USA.
| | - Grant V Hilderbrand
- National Park Service, Alaska Regional Office, 99501, Anchorage, Alaska, USA
| | - Alina L Evans
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway
| | - Ilia Rodushkin
- Division of Geosciences, Luleå University of Technology, 97187, Luleå, Sweden; ALS Scandinavia AB, 97187, Luleå, Sweden
| | - Lindsey S Mangipane
- U.S. Fish and Wildlife Service, Marine Mammals Management, 99503, Anchorage, Alaska, USA
| | - Buck A Mangipane
- Lake Clark National Park and Preserve, National Park Service, 99501, Anchorage, Alaska, USA
| | - David D Gustine
- U.S. Fish and Wildlife Service, Marine Mammals Management, 99503, Anchorage, Alaska, USA
| | - Andreas Zedrosser
- Department of Natural Science and Environmental Health, University of South-Eastern Norway, 3800, Bø in Telemark, Norway; Institute for Wildlife Biology and Game Management, University of Natural Resources and Life Sciences, 1180, Vienna, Austria
| | - Ludovick Brown
- Département de Biologie, Université de Sherbrooke, J1K 2R1, Sherbrooke, Québec, Canada
| | - Jon M Arnemo
- Department of Forestry and Wildlife Management, Inland Norway University of Applied Sciences, Campus Evenstad, 2480, Koppang, Norway; Department of Wildlife, Fish and Environmental Studies, Swedish University of Agricultural Sciences, 901 83, Umeå, Sweden
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5
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Mazziotta A, Borges P, Kangas A, Halme P, Eyvindson K. Spatial trade-offs between ecological and economical sustainability in the boreal production forest. J Environ Manage 2023; 330:117144. [PMID: 36586374 DOI: 10.1016/j.jenvman.2022.117144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Revised: 12/19/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
Economically-oriented forestry aims to sustain timber harvest revenues, while ecologically-oriented management supplies suitable habitat for species using deadwood as primary habitat. As these objectives are conflicting, planning for economic and ecological sustainability involves compromise and trade-offs. We analyze the spatial trade-offs between the economic value from timber harvesting and the volume of deadwood in the boreal forest. We assess these trade-offs from three perspectives: (1) landscape characteristics, affected by conservation strategies; (2) forest management promoting either economic or ecological values; (3) uncertainty in inventory errors undermining the estimate of the two sustainability objectives. To reveal the tradeoffs between the forest economic and ecological values we simulated and optimized a production landscape in Finland 30 years into the future accounting for uncertainty in biomass and deadwood inventories. We found that, with a limited reduction in timber harvesting (7%), (i) the amount of deadwood increased more in non-aggregated (45%) than in aggregated (16%) stands, (ii) constraining stands in adjacent areas further increased deadwood (21%) respect to the matrix and (iii) 7% of connected stand area harbored ≥20 m3/ha deadwood supporting survival of near-threatened species. Our results demonstrate that the structure of the landscape for biodiversity can be improved with limited economic losses. However, improving habitat configuration requires larger economic losses than only increasing habitat amount, but its ecological benefits are larger both for common and red-listed species. We found that management oriented towards stand aggregation not only creates connected areas with high deadwood of high value biodiversity but also improves the value of the whole matrix by decreasing intensive timber harvesting and energy wood collection. Finally, we found that uncertainties alter the estimate of the potential of the forest landscape to supply deadwood, and this can affect the choice of management actions to allocate over the landscape. To conclude, our results demonstrate the trade-offs between economic forest use and conservation are affected differently by landscape characteristics, forest management and uncertainty in inventory errors. As such these drivers should be considered when optimizing the forest for multiple uses.
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Affiliation(s)
| | - Paulo Borges
- Natural Resources Institute Finland (Luke), Helsinki, Finland
| | - Annika Kangas
- Natural Resources Institute Finland (Luke), Joensuu, Finland
| | - Panu Halme
- Dept. of Biological and Environmental Science, University of Jyväskylä, Jyväskylä, Finland; School of Resource Wisdom, University of Jyväskylä, Finland
| | - Kyle Eyvindson
- Natural Resources Institute Finland (Luke), Helsinki, Finland; Norwegian University of Life Sciences (NMBU), Faculty of Environmental Sciences and Natural Resource Management, Ås, Norway
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6
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Krickov IV, Lim AG, Shirokova LS, Korets MА, Karlsson J, Pokrovsky OS. Environmental controllers for carbon emission and concentration patterns in Siberian rivers during different seasons. Sci Total Environ 2023; 859:160202. [PMID: 36395838 DOI: 10.1016/j.scitotenv.2022.160202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 11/11/2022] [Accepted: 11/11/2022] [Indexed: 06/16/2023]
Abstract
Despite the importance of small and medium size rivers of Siberian boreal zone in greenhouse gases (GHG) emission, major knowledge gaps exist regarding its temporal variability and controlling mechanisms. Here we sampled 11 pristine rivers of the southern taiga biome (western Siberia Lowland, WSL), ranging in watershed area from 0.8 to 119,000 km2, to reveal temporal pattern and examine main environmental controllers of GHG emissions from the river water surfaces. Floating chamber measurements demonstrated that CO2 emissions from water surface decreased by 2 to 4-folds from spring to summer and autumn, were independent of the size of the watershed and stream order and did not exhibit sizable (>30 %, regardless of season) variations between day and night. The CH4 concentrations and fluxes increased in the order "spring ≤ summer < autumn" and ranged from 1 to 15 μmol L-1 and 5 to 100 mmol m-2 d-1, respectively. The CO2 concentrations and fluxes (range from 100 to 400 μmol L-1 and 1 to 4 g C m-2 d-1, respectively) were positively correlated with dissolved and particulate organic carbon, total nitrogen and bacterial number of the water column. The CH4 concentrations and fluxes were positively correlated with phosphate and ammonia concentrations. Of the landscape parameters, positive correlations were detected between riparian vegetation biomass and CO2 and CH4 concentrations. Over the six-month open-water period, areal emissions of C (>99.5 % CO2; <0.5 % CH4) from the watersheds of 11 rivers were equal to the total downstream C export in this part of the WSL. Based on correlations between environmental controllers (watershed land cover and the water column parameters), we hypothesize that the fluxes are largely driven by riverine mineralization of terrestrial dissolved and particulate OC, coupled with respiration at the river bottom and riparian sediments. It follows that, under climate warming scenario, most significant changes in GHG regimes of western Siberian rivers located in permafrost-free zone may occur due to changes in the riparian zone vegetation and water coverage of the floodplains.
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Affiliation(s)
- Ivan V Krickov
- BIO-GEO-CLIM Laboratory, Tomsk State University, Tomsk 634050, Russia
| | - Artem G Lim
- BIO-GEO-CLIM Laboratory, Tomsk State University, Tomsk 634050, Russia
| | - Liudmila S Shirokova
- Geosciences and Environment Toulouse, UMR 5563 CNRS, Univeristy of Toulouse, 14 Avenue Edouard Belin, 31400 Toulouse, France; N. Laverov Federal Center for Integrated Arctic Research, Russian Academy of Sciences, Arkhangelsk 163000, Russia
| | - Mikhail А Korets
- V.N. Sukachev Institute of Forest, Siberian Branch of Russian Academy of Sciences, Krasnoyarsk 660036, Russia
| | - Jan Karlsson
- Climate Impacts Research Centre (CIRC), Department of Ecology and Environmental Science, Umeå University, Linnaeus väg 6, 901 87 Umeå, Sweden
| | - Oleg S Pokrovsky
- Geosciences and Environment Toulouse, UMR 5563 CNRS, Univeristy of Toulouse, 14 Avenue Edouard Belin, 31400 Toulouse, France.
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McDonough AM, Watmough SA. Interactive effects of precipitation and above canopy nitrogen deposition on understorey vascular plants in a jack pine (Pinus banksiana) forest in northern Alberta, Canada. Sci Total Environ 2023; 855:158708. [PMID: 36099949 DOI: 10.1016/j.scitotenv.2022.158708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2022] [Revised: 09/08/2022] [Accepted: 09/08/2022] [Indexed: 06/15/2023]
Abstract
Elevated nitrogen (N) deposition in the bituminous sands region of northern Alberta, Canada is localized but expected to increase over time. Here we seek to determine the effects of above canopy N deposition on understorey vascular plants in a jack pine (Pinus banksiana) stand in a five-year experimental study. Aqueous N (ammonium nitrate) was applied four times annually (May through October) via helicopter above the canopy between 2011 and 2015 across a narrow but environmentally relevant N deposition gradient (0, 5, 10, 15, 20 and 25 kg N ha-1 yr-1). Changes in vascular plant species richness, diversity and total vascular cover were best explained by throughfall water flux, but the positive responses to precipitation decreased with increasing N application. Arctostaphylos uva-ursi and Maianthemum canadense showed positive cover increases in wet years; however, the positive cover expansion at ≥5 kg N ha-1 yr-1 treatments was suppressed relative to controls. Total cover expansion was muted in low precipitation years in treatments ≥10 kg N ha-1 yr-1. In contrast, Vaccinium vitis-idaea cover changes ≥10 kg N ha-1 yr-1 were consistently negative. There were no differences in soil net N mineralization rates, plant foliar N or NO3- leaching among treatments. We conjecture the extensive moss/lichen layer of the forest floor that accumulates most of incoming N in throughfall allows them to outcompete vascular plants for water during higher precipitation years, effectively reducing vascular cover expansion relative to controls. This work suggests the response of vascular plants in xeric jack pine ecosystems may interact with climate and these interactions should be considered in risk assessment studies.
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Affiliation(s)
- Andrew M McDonough
- Ontario Ministry of the Environment, Conservation and Parks, 125 Resources Road, Etobicoke, Ontario MP9 3V6, Canada.
| | - Shaun A Watmough
- School of the Environment, Trent University, 1600 West Bank Drive, Peterborough, Ontario K9J 7B8, Canada
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Dieleman CM, Day NJ, Holloway JE, Baltzer J, Douglas TA, Turetsky MR. Carbon and nitrogen cycling dynamics following permafrost thaw in the Northwest Territories, Canada. Sci Total Environ 2022; 845:157288. [PMID: 35839897 DOI: 10.1016/j.scitotenv.2022.157288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Revised: 07/06/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
Rapid climate warming across northern high latitudes is leading to permafrost thaw and ecosystem carbon release while simultaneously impacting other biogeochemical cycles including nitrogen. We used a two-year laboratory incubation study to quantify concomitant changes in carbon and nitrogen pool quantity and quality as drivers of potential CO2 production in thawed permafrost soils from eight soil cores collected across the southern Northwest Territories (NWT), Canada. These data were contextualized via in situ annual thaw depth measurements from 2015 to 2019 at 40 study sites that varied in burn history. We found with increasing time since experimental thaw the dissolved carbon and nitrogen pool quality significantly declined, indicating sustained microbial processing and selective immobilization across both pools. Piecewise structural equation modeling revealed CO2 trends were predominantly predicted by initial soil carbon content with minimal influence of dissolved phase carbon. Using these results, we provide a first-order estimate of potential near-surface permafrost soil losses of up to 80 g C m-2 over one year in southern NWT, exceeding regional historic mean primary productivity rates in some areas. Taken together, this research provides mechanistic knowledge needed to further constrain the permafrost‑carbon feedback and parameterize Earth system models, while building on empirical evidence that permafrost soils are at high risk of becoming weaker carbon sinks or even significant carbon sources under a changing climate.
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Affiliation(s)
- Catherine M Dieleman
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada; School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada.
| | - Nicola J Day
- Biology Department, Wilfrid Laurier University, Waterloo, Ontario, Canada; School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
| | - Jean E Holloway
- Department of Geography, Environment and Geomatics, University of Ottawa, Ontario, Canada
| | - Jennifer Baltzer
- Biology Department, Wilfrid Laurier University, Waterloo, Ontario, Canada
| | - Thomas A Douglas
- U.S. Army Cold Regions Research and Engineering Laboratory, Fort Wainwright, AK, USA
| | - Merritt R Turetsky
- Department of Integrative Biology, University of Guelph, Guelph, Ontario, Canada; Institute of Arctic and Alpine Research, Department of Ecology and Evolutionary Biology, University of Colorado Boulder, Boulder, CO, USA
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Hupperts SF, Lilleskov EA. Predictors of taxonomic and functional composition of black spruce seedling ectomycorrhizal fungal communities along peatland drainage gradients. Mycorrhiza 2022; 32:67-81. [PMID: 35034180 DOI: 10.1007/s00572-021-01060-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 11/24/2021] [Indexed: 06/14/2023]
Abstract
Many trees depend on symbiotic ectomycorrhizal fungi for nutrients in exchange for photosynthetically derived carbohydrates. Trees growing in peatlands, which cover 3% of the earth's terrestrial surface area yet hold approximately one-third of organic soil carbon stocks, may benefit from ectomycorrhizal fungi that can efficiently forage for nutrients and degrade organic matter using oxidative enzymes such as class II peroxidases. However, such traits may place a higher carbon cost on both the fungi and host tree. To investigate these trade-offs that might structure peatland ectomycorrhizal fungal communities, we sampled black spruce (Picea mariana (Mill.)) seedlings along 100-year-old peatland drainage gradients in Minnesota, USA, that had resulted in higher soil nitrogen and canopy density. Structural equation models revealed that the relative abundance of the dominant ectomycorrhizal fungal genus, Cortinarius, which is known for relatively high fungal biomass coupled with elevated class II peroxidase potential, was negatively linked to site fertility but more positively affected by recent host stem radial growth, suggesting carbon limitation. In contrast, Cenococcum, known for comparatively lower fungal biomass and less class II peroxidase potential, was negatively linked to host stem radial growth and unrelated to site fertility. Like Cortinarius, the estimated relative abundance of class II peroxidase genes in the ectomycorrhizal community was more related to host stem radial growth than site fertility. Our findings indicate a trade-off between symbiont foraging traits and associated carbon costs that consequently structure seedling ectomycorrhizal fungal communities in peatlands.
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Affiliation(s)
- Stefan F Hupperts
- College of Forest Resources and Environmental Science, Michigan Technological University, Houghton, MI, USA.
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Umeå, Sweden.
| | - Erik A Lilleskov
- Forestry Sciences Laboratory, USDA Forest Service, Northern Research Station, Houghton, MI, USA.
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Black TA, White MS, Blais JM, Hollebone B, Orihel DM, Palace VP, Rodriguez-Gil JL, Hanson ML. Surface oil is the primary driver of macroinvertebrate impacts following spills of diluted bitumen in freshwater. Environ Pollut 2021; 290:117929. [PMID: 34416496 DOI: 10.1016/j.envpol.2021.117929] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2021] [Revised: 08/04/2021] [Accepted: 08/05/2021] [Indexed: 06/13/2023]
Abstract
The response of freshwater invertebrates following accidental releases of oil is not well understood. This knowledge gap is more substantial for unconventional oils such as diluted bitumen (dilbit). We evaluated the effects of dilbit on insect emergence and benthic invertebrates by conducting experimental spills in limnocorrals (10-m diameter; ~100-m3) deployed in a boreal lake at the IISD-Experimental Lakes Area, Canada. The study included seven dilbit treatments (spill volumes ranged from 1.5 L [1:66,000, oil:water, v/v] to 180 L [1:590, oil:water, v/v]), two controls, and additional lake reference sites, monitored for 11 weeks. Invertebrate emergence declined at the community level following oil addition in a significantly volume-dependent manner, and by 93-100 % over the 11 weeks following the spill in the highest treatment. Dilbit altered community structure of benthic invertebrates, but not abundance. One-year post-spill and following oil removal using traditional skimming and absorption techniques, benthic richness and abundance were greater among all treatments than the previous year. These results indicate that recovery in community composition is possible following oil removal from a lake ecosystem. Research is needed concerning the mechanisms by which surface oil directly affect adult invertebrates, whether through limiting oviposition, limiting emergence, or both. The response of benthic communities to sediment tar mats is also warranted.
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Affiliation(s)
- T A Black
- Department of Environment & Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
| | - M S White
- Ecometrix, 6800 Campobello Road, Mississauga, Ontario, Canada.
| | - J M Blais
- Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 9A7, Canada.
| | - B Hollebone
- Emergencies Science and Technology Division, Environment and Climate Change Canada, Ottawa, Ontario, K1V 1H2, Canada.
| | - D M Orihel
- School of Environmental Studies and Department of Biology, Queen's University, Kingston, Ontario, K7L 3N6, Canada.
| | - V P Palace
- International Institute for Sustainable Development - Experimental Lakes Area (IISD-ELA), Winnipeg, Manitoba, R3B 0T4, Canada.
| | - J L Rodriguez-Gil
- Department of Environment & Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada; Department of Biology, University of Ottawa, Ottawa, Ontario, K1N 9A7, Canada; International Institute for Sustainable Development - Experimental Lakes Area (IISD-ELA), Winnipeg, Manitoba, R3B 0T4, Canada.
| | - M L Hanson
- Department of Environment & Geography, University of Manitoba, Winnipeg, Manitoba, R3T 2N2, Canada.
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11
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Metcalfe JZ. C 3 plant isotopic variability in a boreal mixed woodland: implications for bison and other herbivores. PeerJ 2021; 9:e12167. [PMID: 34631314 PMCID: PMC8466085 DOI: 10.7717/peerj.12167] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Accepted: 08/26/2021] [Indexed: 11/20/2022] Open
Abstract
Plant isotopic baselines are critical for accurately reconstructing ancient diets and environments and for using stable isotopes to monitor ecosystem conservation. This study examines the stable carbon and nitrogen isotope compositions (δ 13C, δ 15N) of terrestrial C3 plants in Elk Island National Park (EINP), Alberta, Canada, with a focus on plants consumed by grazers. EINP is located in a boreal mixed woodland ecozone close to the transition area between historic wood and plains bison habitats, and is currently home to separate herds of wood and plains bison. For this study, 165 C3 plant samples (grasses, sedges, forbs, shrubs, and horsetail) were collected from three habitat types (open, closed, and wet) during two seasons (summer and fall). There were no statistically significant differences in the δ 13C or δ 15N values of grasses, sedges, shrubs and forbs. On the other hand, plant δ 13C and δ 15N values varied among habitats and plant parts, and the values increased from summer to fall. These results have several implications for interpreting herbivore tissue isotopic compositions: (1) consuming different proportions of grasses, sedges, shrubs, and forbs might not result in isotopic niche partitioning, (2) feeding in different microhabitats or selecting different parts of the same types of plants could result in isotopic niche partitioning, and (3) seasonal isotopic changes in herbivore tissues could reflect seasonal isotopic changes in dietary plants rather than (or in addition to) changes in animal diet or physiology. In addition, the positively skewed plant δ 15N distributions highlight the need for researchers to carefully evaluate the characteristics of their distributions prior to reporting data (e.g., means, standard deviations) or applying statistical models (e.g., parametric tests that assume normality). Overall, this study reiterates the importance of accessing ecosystem-specific isotopic baselines for addressing research questions in archaeology, paleontology, and ecology.
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Affiliation(s)
- Jessica Z Metcalfe
- Department of Anthropology, Lakehead University, Thunder Bay, Ontario, Canada
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Chasmer L, Lima EM, Mahoney C, Hopkinson C, Montgomery J, Cobbaert D. Shrub changes with proximity to anthropogenic disturbance in boreal wetlands determined using bi-temporal airborne lidar in the Oil Sands Region, Alberta Canada. Sci Total Environ 2021; 780:146638. [PMID: 34030337 DOI: 10.1016/j.scitotenv.2021.146638] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 03/17/2021] [Accepted: 03/17/2021] [Indexed: 06/12/2023]
Abstract
In this study, we used bi-temporal airborne lidar data to compare changes in vegetation height proximal to anthropogenic disturbances in the Oil Sands Region of Alberta, Canada. We hypothesize that relatively low-impact disturbances such as seismic lines will increase the fragmentation of wetlands, resulting in shrub growth. Bi-temporal lidar data collected circa 2008 and 2018 were used to identify correspondence between the density of anthropogenic disturbances, wetland shape complexity and changes in vegetation height within >1800 wetlands near Fort McKay, Alberta, Canada. We found that up to 50% of wetlands were disturbed by anthropogenic disturbance in some parts of the region, with the highest proportional disturbance occurring within fens. Areas of dense anthropogenic disturbance in bogs resulted in increased growth and expansion of shrubs, while we found the opposite to occur in fens and swamps during the 10-year period. Up to 30% of bogs had increased shrubification, while shrub changes in fens and swamps varied depending on density of disturbance and did not necessarily correspond with shrub growth. As wetland shapes became increasingly elongated, the prevalence of shrubs declined between the two time periods, which may be associated with hydrological drivers (e.g. elongated may indicate surface and ground-water discharge influences). The results of this study indicate that linear disturbances such as seismic lines, considered to have relatively minimal impacts on ecosystems, can impact proximal wetland shape, fragmentation and vegetation community changes, especially in bogs.
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Affiliation(s)
- L Chasmer
- Dept. of Geography and Environment, University of Lethbridge, Lethbridge, AB, Canada.
| | - E Moura Lima
- Graduate Program in Forest Engineering, Universidade Federal de Santa Maria, Camobi, Santa Maria, RS, Brazil
| | - C Mahoney
- Alberta Environment and Parks, Government of Alberta, Edmonton, AB, Canada
| | - C Hopkinson
- Dept. of Geography and Environment, University of Lethbridge, Lethbridge, AB, Canada
| | - J Montgomery
- Alberta Environment and Parks, Government of Alberta, Edmonton, AB, Canada
| | - D Cobbaert
- Alberta Environment and Parks, Government of Alberta, Edmonton, AB, Canada
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13
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Stuart JEM, Holland-Moritz H, Jean M, Miller SN, Ponciano JM, McDaniel SF, Mack MC. The relationship of C and N stable isotopes to high-latitude moss-associated N 2 fixation. Oecologia 2021. [PMID: 34319437 DOI: 10.1007/s00442-021-05005-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 07/23/2021] [Indexed: 10/20/2022]
Abstract
Moss-associated N2 fixation by epiphytic microbes is a key biogeochemical process in nutrient-limited high-latitude ecosystems. Abiotic drivers, such as temperature and moisture, and the identity of host mosses are critical sources of variation in N2 fixation rates. An understanding of the potential interaction between these factors is essential for predicting N inputs as moss communities change with the climate. To further understand the drivers and results of N2 fixation rate variation, we obtained natural abundance values of C and N isotopes and an associated rate of N2 fixation with 15N2 gas incubations in 34 moss species collected in three regions across Alaska, USA. We hypothesized that δ15N values would increase toward 0‰ with higher N2 fixation to reflect the increasing contribution of fixed N2 in moss biomass. Second, we hypothesized that δ13C and N2 fixation would be positively related, as enriched δ13C signatures reflect abiotic conditions favorable to N2 fixation. We expected that the magnitude of these relationships would vary among types of host mosses, reflecting differences in anatomy and habitat. We found little support for our first hypothesis, with only a modest positive relationship between N2 fixation rates and δ15N in a structural equation model. We found a significant positive relationship between δ13C and N2 fixation only in Hypnales, where the probability of N2 fixation activity reached 95% when δ13C values exceeded - 30.4‰. We conclude that moisture and temperature interact strongly with host moss identity in determining the extent to which abiotic conditions impact associated N2 fixation rates.
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Ter-Mikaelian MT, Gonsamo A, Chen JM, Mo G, Chen J. Historical and future carbon stocks in forests of northern Ontario, Canada. Carbon Balance Manag 2021; 16:21. [PMID: 34264423 PMCID: PMC8281711 DOI: 10.1186/s13021-021-00184-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Forests in the Far North of Ontario (FNO), Canada, are likely the least studied in North America, and quantifying their current and future carbon (C) stocks is the first step in assessing their potential role in climate change mitigation. Although the FNO forests are unmanaged, the latter task is made more important by growing interest in developing the region's natural resources, primarily for timber harvesting. In this study, we used a combination of field and remotely sensed observations with a land surface model to estimate forest C stocks in the FNO forests and to project their future dynamics. The specific objective was to simulate historical C stocks for 1901-2014 and future C stocks for 2015-2100 for five shared socioeconomic pathway (SSP) scenarios selected as high priority scenarios for the 6th Assessment Report on Climate Change. RESULTS Carbon stocks in live vegetation in the FNO forests remained relatively stable between 1901 and 2014 while soil organic carbon (SOC) stocks steadily declined, losing about 16% of their initial value. At the end of the historical simulation (in 2014), the stocks were estimated at 19.8, 46.4, and 66.2 tCha-1 in live vegetation, SOC, and total ecosystem pools, respectively. Projections for 2015-2100 indicated effectively no substantial change in SOC stocks, while live vegetation C stocks increased, accelerating their growth in the second half of the twenty-first century. These results were consistent among all simulated SSP scenarios. Consequently, increase in total forest ecosystem C stocks by 2100 ranged from 16.7 to 20.7% of their value in 2015. Simulations with and without wildfires showed the strong effect of fire on forest C stock dynamics during 2015-2100: inclusion of wildfires reduced the live vegetation increase by half while increasing the SOC pool due to higher turnover of vegetation C to SOC. CONCLUSIONS Forest ecosystem C stock estimates at the end of historical simulation period were at the lower end but within the range of values reported in the literature for northern boreal forests. These estimates may be treated as conservatively low since the area included in the estimates is poorly studied and some of the forests may be on peat deposits rather than mineral soils. Future C stocks were projected to increase in all simulated SSP scenarios, especially in the second half of the twenty-first century. Thus, during the projected period forest ecosystems of the FNO are likely to act as a C sink. In light of growing interest in developing natural resources in the FNO, collecting more data on the status and dynamics of its forests is needed to verify the above-presented estimates and design management activities that would maintain their projected C sink status.
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Affiliation(s)
- Michael T Ter-Mikaelian
- Ontario Forest Research Institute, Ontario Ministry of Natural Resources and Forestry, 1235 Queen Street E., Sault Ste. Marie, ON, P6A 2E5, Canada.
| | - Alemu Gonsamo
- School of Earth, Environment & Society, McMaster University, 1280 Main Street West, Hamilton, ON, L8S 4S4, Canada
| | - Jing M Chen
- Department of Geography and Planning, University of Toronto, 100 St. George St, Toronto, ON, M5S 3G3, Canada
| | - Gang Mo
- Department of Geography and Planning, University of Toronto, 100 St. George St, Toronto, ON, M5S 3G3, Canada
| | - Jiaxin Chen
- Ontario Forest Research Institute, Ontario Ministry of Natural Resources and Forestry, 1235 Queen Street E., Sault Ste. Marie, ON, P6A 2E5, Canada
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Nelson K, Thompson D, Hopkinson C, Petrone R, Chasmer L. Peatland-fire interactions: A review of wildland fire feedbacks and interactions in Canadian boreal peatlands. Sci Total Environ 2021; 769:145212. [PMID: 33486170 DOI: 10.1016/j.scitotenv.2021.145212] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Revised: 01/08/2021] [Accepted: 01/11/2021] [Indexed: 06/12/2023]
Abstract
Boreal peatlands store a disproportionately large quantity of soil carbon (C) and play a critical role within the global C-climate system; however, with climatic warming, these C stores are at risk. Increased wildfire frequency and severity are expected to increase C loss from boreal peatlands, contributing to a shift from C sink to source. Here, we provide a comprehensive review of pre- and post-fire hydrological and ecological interactions that affect the likelihood of peatland burning, address the connections between peatland fires and the C-climate cycle, and provide a conceptual model of peatland processes as they relate to wildland fire, hydro-climate, and ecosystem change. Despite negative ecohydrological feedback mechanisms that may compensate for increased C loss initially, the cumulative effects of climatic warming, anthropogenic peatland fragmentation, and subsequent peatland drying will increase C loss to the atmosphere, driving a positive C feedback cycle. However, the extent to which negative and positive feedbacks will compensate for one another and the timelines for each remains unclear. We suggest that a multi-disciplinary approach of combining process knowledge with remotely sensed data and ecohydrological and wildland fire models is essential for better understanding the role of boreal peatlands and wildland fire in the global climate system.
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Affiliation(s)
- K Nelson
- Dept. of Geography and Environment, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada.
| | - D Thompson
- Canadian Forest Service, Great Lakes Forestry Centre, Sault Ste. Marie, ON P6A 2E5, Canada
| | - C Hopkinson
- Dept. of Geography and Environment, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
| | - R Petrone
- Dept. of Geography and Environmental Management, University of Waterloo, Waterloo, ON N2L 3G1, Canada
| | - L Chasmer
- Dept. of Geography and Environment, University of Lethbridge, Lethbridge, AB T1K 3M4, Canada
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Williams KE, Menning DM, Wald EJ, Talbot SL, Rattenbury KL, Prugh LR. Using next generation sequencing of alpine plants to improve fecal metabarcoding diet analysis for Dall's sheep. BMC Res Notes 2021; 14:173. [PMID: 33962681 DOI: 10.1186/s13104-021-05590-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Accepted: 04/28/2021] [Indexed: 12/11/2022] Open
Abstract
Objectives Dall’s sheep (Ovis dalli dalli) are important herbivores in the mountainous ecosystems of northwestern North America, and recent declines in some populations have sparked concern. Our aim was to improve capabilities for fecal metabarcoding diet analysis of Dall’s sheep and other herbivores by contributing new sequence data for arctic and alpine plants. This expanded reference library will provide critical reference sequence data that will facilitate metabarcoding diet analysis of Dall’s sheep and thus improve understanding of plant-animal interactions in a region undergoing rapid climate change. Data description We provide sequences for the chloroplast rbcL gene of 16 arctic-alpine vascular plant species that are known to comprise the diet of Dall’s sheep. These sequences contribute to a growing reference library that can be used in diet studies of arctic herbivores. Supplementary Information The online version contains supplementary material available at 10.1186/s13104-021-05590-z.
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17
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Voinorosky CL, Stewart KJ. Drift, dissipation and risk to wildlife following targeted herbicide applications on boreal transmission rights-of-way. J Environ Manage 2021; 280:111860. [PMID: 33373816 DOI: 10.1016/j.jenvman.2020.111860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/04/2020] [Accepted: 12/15/2020] [Indexed: 06/12/2023]
Abstract
Herbicide use on boreal transmission line rights-of-way has been relatively limited compared to more temperate regions and therefore challenges exist in estimating and communicating the associated risks. Herbicides directly enter the ecosystem through deposition on vegetation and soils and can be a vector of contamination to browsing herbivores. Triclopyr drift and foliage concentrations were quantified following basal bark (Garlon RTU) and low-volume foliar (Garlon XRT) field treatments to aspen (Populus tremuloides) saplings and willow (Salix bebbiana) shrubs, respectively. Greater drift concentrations localized at the stem base were observed following basal bark treatments. Conversely, concentrations in foliage following the low-volume foliar treatment (DT50 = 5.7 days and DT90 = 34.6 days) were much higher than following basal bark treatment, which also required two days to translocate into the leaves. However, dissipation was rapid from both application methods and triclopyr in foliage was less than 20 μg g-1 a year following application. A risk assessment revealed an acceptable level of risk for acute toxicity to wildlife browsing on contaminated leaves from the residues detected in this study; however, an unacceptable level of risk for chronic toxicity to long-term browsing moose. Site-specific data regarding browsing behaviour on herbicide treated rights-of-ways and species-specific reference values are needed to improve confidence in the tier-two risk assessment. Basal bark application is ideal when stem density is lower and toxic effects for herbivores is of concern and low-volume foliar applications are best suited in areas with higher stem density when off-target herbicide deposition is less acceptable.
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Affiliation(s)
| | - Katherine J Stewart
- Toxicology Centre, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada; Department of Soil Science, University of Saskatchewan, Saskatoon, SK S7N 5A8, Canada.
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Majasalmi T, Rautiainen M. Representation of tree cover in global land cover products: Finland as a case study area. Environ Monit Assess 2021; 193:121. [PMID: 33576910 PMCID: PMC7880955 DOI: 10.1007/s10661-021-08898-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Accepted: 01/17/2021] [Indexed: 06/12/2023]
Abstract
Forest extent mapping is required for climate modeling and monitoring changes in ecosystem state. Different global land cover (LC) products employ simple tree cover (referred also as "forest cover" or even "vegetation cover") definitions to differentiate forests from non-forests. Since 1990, a large number of forest extent maps have become available. Although many studies have compared forest extent data, they often use old data (i.e., around the year 2000). In this study, we assessed tree cover representations of three different annual, global LC products (MODIS VCF (MOD44B, Collection 6 (C6)), MCD12Q1 (C6), and CCI LC (v.2.1.1)) using the Finnish Multi-Source National Forest Inventory (MS-NFI) data for the year 2017. In addition, we present an intercomparison approach for analyzing spatial representations of coniferous and deciduous species. Intercomparison of different LC products is often overlooked due to challenges involved in non-standard and overlapping LC class definitions. Global LC products are used for monitoring changes in land use and land cover and modeling of surface fluxes. Given that LC is a major driver of global change through modifiers such as land surface albedo, more attention should be paid to spatial mapping of coniferous and deciduous species. Our results show that tree cover was either overestimated or underestimated depending on the LC product, and classification accuracy varied between 42 and 75%. Intercomparison of the LC products showed large differences in conifer and deciduous species spatial distributions. Spatial mapping of coniferous and deciduous tree covers was the best represented by the CCI LC product as compared with the reference MS-NFI data.
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Affiliation(s)
- Titta Majasalmi
- School of Engineering, Department of Built Environment, Aalto University, P.O. Box 14100, 00076, Aalto, Finland.
| | - Miina Rautiainen
- School of Engineering, Department of Built Environment, Aalto University, P.O. Box 14100, 00076, Aalto, Finland
- School of Electrical Engineering, Department of Electronics and Nanoengineering, Aalto University, P.O. Box 14100, 00076, Aalto, Finland
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Vitt DH, House M, Kitchen S, Wieder RK. A protocol for monitoring plant responses to changing nitrogen deposition regimes in Alberta bogs. Environ Monit Assess 2020; 192:743. [PMID: 33136233 PMCID: PMC7606289 DOI: 10.1007/s10661-020-08645-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Accepted: 09/28/2020] [Indexed: 05/24/2023]
Abstract
Bogs are nutrient poor, acidic ecosystems that receive their water and nutrients entirely from precipitation (= ombrogenous) and as a result are sensitive to nutrient loading from atmospheric sources. Bogs occur frequently on the northern Alberta landscape, estimated to cover 6% of the Athabasca Oil Sands Area. As a result of oil sand extraction and processing, emissions of nitrogen (N) and sulfur (S) to the atmosphere have led to increasing N and S deposition that have the potential to alter the structure and function of these traditionally nutrient-poor ecosystems. At present, no detailed protocol is available for monitoring potential change of these sensitive ecosystems. We propose a user-friendly protocol that will monitor potential plant and lichen responses to future environmental inputs of nutrients and provide a structured means for collecting annual data. The protocol centers on measurement of five key plant/lichen attributes, including changes in (1) plant abundances, (2) dominant shrub annual growth and primary production, (3) lichen health estimated through chlorophyll/phaeophytin concentrations, (4) Sphagnum annual growth and production, and (5) annual growth of the dominant tree species (Picea mariana). We placed five permanent plots in each of six bogs located at different distances from the center of oil sand extraction and sampled these for 2 years (2018 and 2019). We compared line intercept with point intercept plant assessments using NMDS ordination, concluding that both methods provide comparable data. These data indicated that each of our six bog sites differ in key species abundances. Structural differences were apparent for the six sites between years. These differences were mostly driven by changes in Vaccinium oxycoccos, not the dominant shrubs. We developed allometric growth equations for the dominant two shrubs (Rhododendron groenlandicum and Chamaedaphne calyculata). Equations developed for each of the six sites produced growth values that were not different from one another nor from one developed using data from all sites. Annual growth of R. groenlandicum differed between sites, but not years, whereas growth of C. calyculata differed between the 2 years with more growth in 2018 compared with 2019. In comparison, Sphagnum plant density and stem bulk density both had strong site differences, with stem mass density higher in 2019. When combined, annual production of S. fuscum was greater in 2019 at three sites and not different at three of the sites. Chlorophyll and phaeophytin concentrations from the epiphytic lichen Evernia mesomorpha also differed between sites and years. This protocol for field assessments of five key plant/lichen response variables indicated that both site and year are factors that must be accounted for in future assessments. A portion of the site variation was related to patterns of N and S deposition.
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Affiliation(s)
- Dale H Vitt
- School of Biological Sciences, Southern Illinois University, Carbondale, IL, 62901, USA.
| | - Melissa House
- School of Biological Sciences, Southern Illinois University, Carbondale, IL, 62901, USA
| | - Samantha Kitchen
- School of Biological Sciences, Southern Illinois University, Carbondale, IL, 62901, USA
| | - R Kelman Wieder
- Department Biology, Villanova University, Villanova, PA, 19085, USA
- Center for Biodiversity and Ecosystem Stewardship, Villanova University, Villanova, PA, 19085, USA
- Faculty of Science and Technology, Athabasca University, Athabasca, Alberta, Canada
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20
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Emmerton CA, Cooke CA, Hustins S, Silins U, Emelko MB, Lewis T, Kruk MK, Taube N, Zhu D, Jackson B, Stone M, Kerr JG, Orwin JF. Severe western Canadian wildfire affects water quality even at large basin scales. Water Res 2020; 183:116071. [PMID: 32717650 DOI: 10.1016/j.watres.2020.116071] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Revised: 06/04/2020] [Accepted: 06/15/2020] [Indexed: 06/11/2023]
Abstract
Wildfires can have severe and lasting impacts on the water quality of aquatic ecosystems. However, our understanding of these impacts is founded primarily from studies of small watersheds with well-connected runoff regimes. Despite the predominance of large, low-relief rivers across the fire-prone Boreal forest, it is unclear to what extent and duration wildfire-related material (e.g., ash) can be observed within these systems that typically buffer upstream disturbance signals. Following the devastating 2016 Fort McMurray wildfire in western Canada, we initiated a multi-faceted water quality monitoring program that suggested brief (hours to days) wildfire signatures could be detected in several large river systems, particularly following rainfall events greater than 10 mm. Continuous monitoring of flow and water quality showed distinct, precipitation-associated signatures of ash transport in rivers draining expansive (800-100,000 km2) and partially-burned (<1-22 percent burned) watersheds, which were not evident in nearby unburned regions. Yields of suspended sediment, nutrients (nitrogen, phosphorus) and metals (lead, others) from impacted rivers were 1.2-10 times greater than from those draining unburned regions. Post-fire suspended sediment concentrations in impacted rivers were often larger than pre-fire 95% prediction intervals based on several years of water sampling. These multiple lines of evidence indicate that low-relief landscapes can mobilize wildfire-related material to rivers similarly, though less-intensively and over shorter durations, than headwater regions. We propose that uneven mixing of heavily-impacted tributaries with high-order rivers may partially explain detection of wildfire signals in these large systems that may impact downstream water users.
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Affiliation(s)
- Craig A Emmerton
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada; Department of Biological Sciences, University of Alberta, Edmonton, Alberta, Canada.
| | - Colin A Cooke
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada; Department of Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta, Canada.
| | - Sarah Hustins
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
| | - Uldis Silins
- Department of Renewable Resources, University of Alberta, Edmonton, Alberta, Canada
| | - Monica B Emelko
- Department of Civil and Environmental Engineering, University of Waterloo, Waterloo, Ontario, Canada
| | - Ted Lewis
- Hatfield Consultants, North Vancouver, British Columbia, Canada
| | - Mary K Kruk
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
| | - Nadine Taube
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
| | - Dongnan Zhu
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
| | - Brian Jackson
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
| | - Michael Stone
- Department of Geography and Environmental Management, University of Waterloo, Waterloo, Ontario, Canada
| | - Jason G Kerr
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
| | - John F Orwin
- Alberta Environment and Parks, Edmonton/Calgary, Alberta, Canada
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Wieder RK, Vitt DH, Vile MA, Graham JA, Hartsock JA, Popma JMA, Fillingim H, House M, Quinn JC, Scott KD, Petix M, McMillen KJ. Experimental nitrogen addition alters structure and function of a boreal poor fen: Implications for critical loads. Sci Total Environ 2020; 733:138619. [PMID: 32446046 DOI: 10.1016/j.scitotenv.2020.138619] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2019] [Revised: 04/01/2020] [Accepted: 04/08/2020] [Indexed: 05/24/2023]
Abstract
Bogs and fens cover 6 and 21%, respectively, of the 140,329 km2 Oil Sands Administrative Area in northern Alberta. Regional background atmospheric N deposition is low (<2 kg N ha-1 yr-1), but oil sands development has led to increasing N deposition (as high as 17 kg N ha-1 yr-1). To examine responses to N deposition, over five years, we experimentally applied N (as NH4NO3) to a poor fen near Mariana Lake, Alberta, unaffected by oil sands activities, at rates of 0, 5, 10, 15, 20, and 25 kg N ha-1 yr-1, plus controls (no water or N addition). At Mariana Lake Poor Fen (MLPF), increasing N addition: 1) progressively inhibited N2-fixation; 2) had no effect on net primary production (NPP) of Sphagnum fuscum or S. angustifolium, while stimulating S. magellanicum NPP; 3) led to decreased abundance of S. fuscum and increased abundance of S. angustifolium, S. magellanicum, Andromeda polifolia, Vaccinium oxycoccos, and of vascular plants in general; 4) led to an increase in stem N concentrations in S. angustifolium and S. magellanicum, and an increase in leaf N concentrations in Chamaedaphne calyculata, Andromeda polifolia, and Vaccinium oxycoccos; 5) stimulated root biomass and production; 6) stimulated decomposition of cellulose, but not of Sphagnum or vascular plant litter; and 7) had no or minimal effects on net N mineralization in surface peat, NH4+-N, NO3--N or DON concentrations in surface porewater, or peat microbial composition. Increasing N addition led to a switch from new N inputs being taken up primarily by Sphagnum to being taken up primarily by shrubs. MLPF responses to increasing N addition did not exhibit threshold triggers, but rather began as soon as N additions increased. Considering all responses to N addition, we recommend a critical load for poor fens in Alberta of 3 kg N ha-1 yr-1.
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Affiliation(s)
- R Kelman Wieder
- Department of Biology, Villanova University, Villanova, PA 19085, USA; Faculty of Science and Technology, Athabasca University, Athabasca, Alberta T9S 3A3, Canada; Center for Biodiversity and Ecosystem Stewardship, Villanova University, Villanova, PA 19085, USA.
| | - Dale H Vitt
- Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Melanie A Vile
- Faculty of Science and Technology, Athabasca University, Athabasca, Alberta T9S 3A3, Canada; Department of Geography and the Environment, Villanova University, Villanova, PA 19085, USA
| | - Jeremy A Graham
- Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901, USA; Michigan Tech Research Institute, Ann Arbor, MI 48105, USA
| | - Jeremy A Hartsock
- Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Jacqueline M A Popma
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Hope Fillingim
- Department of Geography and the Environment, Villanova University, Villanova, PA 19085, USA
| | - Melissa House
- Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901, USA
| | - James C Quinn
- Department of Biology, Villanova University, Villanova, PA 19085, USA
| | - Kimberli D Scott
- Department of Biology, Villanova University, Villanova, PA 19085, USA; Center for Biodiversity and Ecosystem Stewardship, Villanova University, Villanova, PA 19085, USA
| | - Meaghan Petix
- Department of Plant Biology, Southern Illinois University, Carbondale, IL 62901, USA
| | - Kelly J McMillen
- Department of Geography and the Environment, Villanova University, Villanova, PA 19085, USA; Texas Tech University, Climate Science Center, Lubbock, TX 79409-3131, USA
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Braaten HFV, de Wit HA, Larssen T, Poste AE. Mercury in fish from Norwegian lakes: The complex influence of aqueous organic carbon. Sci Total Environ 2018; 627:341-348. [PMID: 29426157 DOI: 10.1016/j.scitotenv.2018.01.252] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Revised: 01/24/2018] [Accepted: 01/24/2018] [Indexed: 06/08/2023]
Abstract
Mercury (Hg) concentrations in water and biota are often positively correlated to organic matter (OM), typically measured as total or dissolved organic carbon (TOC/DOC). However, recent evidence suggests that higher OM concentrations inhibit bioaccumulation of Hg. Here, we test how TOC impacts the Hg accumulation in fish in a synoptic study of Methyl-Hg (MeHg) in water and total Hg (THg) in perch (Perca fluviatilis) in 34 boreal lakes in southern Norway. We found that aqueous MeHg (r2 = 0.49, p < 0.0001) and THg (r2 = 0.69, p < 0.0001), and fish THg (r2 = 0.26, p < 0.01) were all positively related with TOC. However, we found declining MeHg bioaccumulation factors (BAFMeHg) for fish with increasing TOC concentrations. The significant correlation between fish THg concentrations and aqueous TOC suggests that elevated fish Hg levels in boreal regions are associated with humic lakes. The declining BAFMeHg with increasing TOC suggest that increased OM promotes increased aqueous Hg concentrations, but lowers relative MeHg bioaccumulation. A mechanistic understanding of the response from OM on BAFMeHg might be found in the metal-complexation properties of OM, where OM complexation of metals reduces their bioavailability. Hence, suggesting that MeHg bioaccumulation becomes less effective at higher TOC, which is particularly relevant when assessing potential responses of fish Hg to predicted future changes in OM inputs to boreal ecosystems. Increased browning of waters may affect fish Hg in opposite directions: an increase of food web exposure to aqueous Hg, and reduced bioavailability of Hg species. However, the negative relationship between BAFMeHg and TOC is challenging to interpret, and carries a great deal of uncertainty, since this relationship may be driven by the underlying correlation between TOC and MeHg (i.e. spurious correlations). Our results suggest that the trade-off between Hg exposure and accumulation will have important implications for the effects of lake browning on Hg transport, bioavailability, and trophodynamics.
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Affiliation(s)
| | - Heleen A de Wit
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo, Norway
| | - Thorjørn Larssen
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo, Norway
| | - Amanda E Poste
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo, Norway
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Ramberg E, Strengbom J, Granath G. Coordination through databases can improve prescribed burning as a conservation tool to promote forest biodiversity. Ambio 2018; 47:298-306. [PMID: 29127668 PMCID: PMC5857265 DOI: 10.1007/s13280-017-0987-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 09/13/2017] [Accepted: 10/09/2017] [Indexed: 06/07/2023]
Abstract
Prescribed fires are a common nature conservation practice. They are executed by several parties with limited coordination among them, and little consideration for wildfire occurrences and habitat requirements of fire-dependent species. Here, we gathered data on prescribed fires and wildfires in Sweden during 2011-2015 to (i) evaluate the importance and spatial extent of prescribed fires compared to wildfires and (ii) illustrate how a database can be used as a management tool for prescribed fires. We found that on average only 0.006% (prescribed 65%, wildfires 35%) of the Swedish forest burns per year, with 58% of the prescribed fires occurring on clearcuts. Also, both wildfires and prescribed fires seem to be important for the survival of fire-dependent species. A national fire database would simplify coordination and make planning and evaluation of prescribed fires more efficient. We propose an adaptive management strategy to improve the outcome of prescribed fires.
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Affiliation(s)
- Ellinor Ramberg
- Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, 750 07 Uppsala, Sweden
| | - Joachim Strengbom
- Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, 750 07 Uppsala, Sweden
| | - Gustaf Granath
- Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, 750 07 Uppsala, Sweden
- Present Address: Department of Plant Ecology and Evolution, Evolutionary Biology Centre, Uppsala University, Norbyvägen 18D, 752 36 Uppsala, Sweden
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Oleinikova OV, Shirokova LS, Drozdova OY, Lapitskiy SA, Pokrovsky OS. Low biodegradability of dissolved organic matter and trace metals from subarctic waters. Sci Total Environ 2018; 618:174-187. [PMID: 29128766 DOI: 10.1016/j.scitotenv.2017.10.340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/24/2017] [Revised: 10/03/2017] [Accepted: 10/31/2017] [Indexed: 06/07/2023]
Abstract
The heterotrophic mineralization of dissolved organic matter (DOM) controls the CO2 flux from the inland waters to the atmosphere, especially in the boreal waters, although the mechanisms of this process and the fate of trace metals associated with DOM remain poorly understood. We studied the interaction of culturable aquatic (Pseudomonas saponiphila) and soil (Pseudomonas aureofaciens) Gammaproteobacteria with seven different organic substrates collected in subarctic settings. These included peat leachate, pine crown throughfall, fen, humic lake, stream, river, and oligotrophic lake with variable dissolved organic carbon (DOC) concentrations (from 4 to 60mgL-1). The highest removal of DOC over 4days of reaction was observed in the presence of P. aureofaciens (33±5%, 43±3% and 53±7% of the initial amount in fen water, humic lake and stream, respectively). P. saponiphila degraded only 5% of DOC in fen water but did not affect all other substrates. Trace elements (TE) were essentially controlled by short-term (0-1h) adsorption on the surface of cells. Regardless of the nature of organic substrate and the identity of bacteria, the degree of adsorption ranged from 20 to 60% for iron (Fe3+), 15 to 55% for aluminum (Al), 10 to 60% for manganese (Mn), 10 to 70% for nickel (Ni), 20 to 70% for copper (Cu), 10 to 60% for yttrium (Y), 30 to 80% for rare earth elements (REE), and 15 to 50% for uranium (UVI). Rapid adsorption of organic and organo-mineral colloids on bacterial cell surfaces is novel and potentially important process, which deserves special investigation. The long-term removal of dissolved Fe and Al was generally consistent with solution supersaturation degree with respect to Fe and Al hydroxides, calculated by visual Minteq model. Overall, the biomass-normalized biodegradability of various allochthonous substrates by culturable bacteria is much lower than that of boreal DOM by natural microbial consortia.
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Affiliation(s)
- Olga V Oleinikova
- GET (Geosciences and Environment Toulouse) UMR 5563 CNRS, University Paul Sabatier, 14 Avenue Edouard Belin, 31400 Toulouse, France; Geological Faculty, Moscow State University, 1 Leninskie Gory, 119234 Moscow, Russia
| | - Liudmila S Shirokova
- GET (Geosciences and Environment Toulouse) UMR 5563 CNRS, University Paul Sabatier, 14 Avenue Edouard Belin, 31400 Toulouse, France; N. Laverov Federal Center for Integrated Arctic Research; IEPS, Russian Academy of Science, 23 Nab. Severnoi Dviny, 163000 Arkhangelsk, Russia
| | - Olga Y Drozdova
- Geological Faculty, Moscow State University, 1 Leninskie Gory, 119234 Moscow, Russia
| | - Sergey A Lapitskiy
- Geological Faculty, Moscow State University, 1 Leninskie Gory, 119234 Moscow, Russia
| | - Oleg S Pokrovsky
- GET (Geosciences and Environment Toulouse) UMR 5563 CNRS, University Paul Sabatier, 14 Avenue Edouard Belin, 31400 Toulouse, France.
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Huser BJ, Futter MN, Wang R, Fölster J. Persistent and widespread long-term phosphorus declines in Boreal lakes in Sweden. Sci Total Environ 2018; 613-614:240-249. [PMID: 28915460 DOI: 10.1016/j.scitotenv.2017.09.067] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2017] [Revised: 09/07/2017] [Accepted: 09/07/2017] [Indexed: 05/14/2023]
Abstract
We present an analysis of long-term (1988-2013; 26years) total phosphorus (TP) concentration trends in 81 Swedish boreal lakes subject to minimal anthropogenic disturbance. Near universal increases in dissolved organic carbon (DOC) concentrations and a widespread but hitherto unexplained decline in TP were observed. Over 50% of the lakes (n=42) had significant declining TP trends over the past quarter century (Sen's slope=2.5%y-1). These declines were linked to catchment processes related to changes in climate, recovery from acidification, and catchment soil properties, but were unrelated to trends in P deposition. Increasing DOC concentrations appear to be masking in-lake TP declines. When the effect of increasing DOC was removed, the small number of positive TP trends (N=5) turned negative and the average decline in TP increased to 3.9%y-1. The greatest relative TP declines occurred in already nutrient poor, oligotrophic systems and TP concentrations have reached the analytical detection limit (1μgL-1) in some lakes. In addition, ongoing oligotrophication may be exacerbated by increased reliance on renewable energy from forest biomass and hydropower. It is a cause of significant concern that potential impairments to lake ecosystem functioning associated with oligotrophication are not well handled by a management paradigm focused exclusively on the negative consequences of increasing phosphorus concentrations.
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Affiliation(s)
- Brian J Huser
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 750 07 Uppsala, Sweden.
| | - Martyn N Futter
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 750 07 Uppsala, Sweden
| | - Rong Wang
- Department of Global Ecology, Carnegie Institution for Science, Stanford, CA 94305, USA
| | - Jens Fölster
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Box 7050, 750 07 Uppsala, Sweden
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26
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Isbister KM, Lamb EG, Stewart KJ. Herbicide Toxicity Testing with Non-Target Boreal Plants: The Sensitivity of Achillea millefolium L. and Chamerion angustifolium L. to Triclopyr and Imazapyr. Environ Manage 2017; 60:136-156. [PMID: 28424880 DOI: 10.1007/s00267-017-0867-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 04/08/2017] [Indexed: 05/25/2023]
Abstract
Terrestrial plant toxicity tests were conducted to determine the sensitivity of two boreal plants, yarrow (Achillea millefolium L.) and fireweed (Chamerion angustifolium L.), to the herbicides imazapyr and triclopyr. Both plants are common non-target species on northern powerline rights-of-way where the impacts of proposed herbicide applications are of concern. In the vegetative vigour test, triclopyr foliar spray caused extensive damage to A. millefolium at <50% of the maximum field application rate (inhibition concentration (IC)50 = 1443.8 g a.i. ha-1) and was lethal to C. angustifolium at the lowest dose tested (1210.9 g a.i. ha-1). Both species demonstrated extremely high sensitivity to imazapyr foliar spray: IC50s = 8.29 g a.i. ha-1 and 4.82 g a.i. ha-1 (<1.5% of the maximum field rate). The seedling emergence and seedling growth tests were conducted in the organic horizon of five boreal soils. Few differences in herbicide bioavailability between soils were detected. Triclopyr limited growth of A. millefolium, C. angustifolium and standard test species Calamagrostis canadensis at low levels (most IC50 estimates between 2-20 µg g-1). For imazapyr, IC50 estimates could not be calculated as there was >75% inhibition of endpoints at the lowest doses of ~2 µg g-1. A foliar application of triclopyr or imazapyr for woody species control would likely cause significant damage to boreal non-target plants. The high sensitivity of both species to herbicide residues in soil indicates long term impacts are dependent on herbicide degradation rates in northern conditions. A. millefolium performed well and is recommended for use in toxicity testing relevant to boreal regions.
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Affiliation(s)
- Krystal M Isbister
- Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, S7N 5A8, SK, Canada
| | - Eric G Lamb
- Department of Plant Sciences, University of Saskatchewan, 51 Campus Drive, Saskatoon, S7N 5A8, SK, Canada
| | - Katherine J Stewart
- Department of Soil Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, S7N 5A8, SK, Canada.
- Yukon Research Centre, Yukon College, 500 College Drive, Whitehorse, Y1A 5K4, YT, Canada.
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27
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Braaten HFV, de Wit HA. Effects of disturbance and vegetation type on total and methylmercury in boreal peatland and forest soils. Environ Pollut 2016; 218:140-149. [PMID: 27552047 DOI: 10.1016/j.envpol.2016.08.029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 08/02/2016] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
Mercury (Hg) concentrations in freshwater fish relates to aquatic Hg concentrations, which largely derives from soil stores of accumulated atmospheric deposition. Hg in catchment soils as a source for aquatic Hg is poorly studied. Here we test if i) peatland soils produce more methylmercury (MeHg) than forest soils; ii) total Hg (THg) concentrations in top soils are determined by atmospheric inputs, while MeHg is produced in the soils; and iii) soil disturbance promotes MeHg production. In two small boreal catchments, previously used in a paired-catchment forest harvest manipulation study, forest soils and peatlands were sampled and analysed for Hg species and additional soil chemistry. In the undisturbed reference catchment, soils were sampled in different vegetation types, of varying productivity as reflected in tree density, where historical data on precipitation and throughfall Hg and MeHg fluxes were available. Upper soil THg contents were significantly correlated to throughfall inputs of Hg, i.e. lowest in the tree-less peatland and highest in the dense spruce forest. For MeHg, top layer concentrations were similar in forest soils and peatlands, likely related to atmospheric input and local production, respectively. The local peatland MeHg production was documented through significantly higher MeHg-to-THg ratios in the deeper soil layer samples. In the disturbed catchment, soils were sampled in and just outside wheeltracks in an area impacted by forest machinery. Here, MeHg concentrations and the MeHg-to-THg ratios in the upper 5 cm were weakly significantly (p = 0.07) and significantly (p = 0.04) different in and outside of the wheeltracks, respectively, suggesting that soil disturbance promotes methylation. Differences in catchment Hg and MeHg streamwater concentrations were not explained by soil Hg and MeHg information, perhaps because hydrological pathways are a stronger determinant of streamwater chemistry than small variations in soil chemistry driven by disturbance and atmospheric inputs of Hg.
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Affiliation(s)
| | - Heleen A de Wit
- Norwegian Institute for Water Research (NIVA), Gaustadalléen 21, N-0349 Oslo, Norway
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28
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Tarvainen O, Tolvanen A. Healing the wounds in the landscape-reclaiming gravel roads in conservation areas. Environ Sci Pollut Res Int 2016; 23:13732-13744. [PMID: 26358210 DOI: 10.1007/s11356-015-5341-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Accepted: 08/28/2015] [Indexed: 06/05/2023]
Abstract
Reclaiming abandoned and unmaintained roads, built originally for forestry and mineral extraction, is an important part of ecological restoration, because the roads running through natural habitats cause fragmentation. The roads can be reclaimed in a passive way by blocking access to the road, but successful seedling recruitment may require additional management due to the physical constraints present at the road. We established a full factorial study to compare the effects of three road reclaiming measures, namely ripping, creation of safe sites by adding mulch and pine seed addition, on soil processes, recovery of understorey vegetation and seedling recruitment in three conservation areas in eastern Finland. We surveyed soil organic matter, frequency and cover of plant functional types, litter and mineral soil, and number of tree seedlings. The soil organic matter was, on average, 1.3-fold in the 50-cm-deep ripping treatment relative to unripped and 20-cm-deep ripping treatments. The germination and survival of deciduous seedlings and grass establishment were promoted by adding mulch. The addition of pine seeds counteracted the seed limitation and enhanced the regeneration of trees. The treatment combination consisting of ripping, adding mulch and pine seed addition enhanced the vegetation succession and tree-seedling recruitment most: the cover of grasses, herbs and ericaceous dwarf shrubs was 1.3-7.6-fold and the number of coniferous tree seedlings was 3.4-7.1-fold relative to the other treatment combinations. Differences between short-term (1-3 years) and longer-term (6 years) results indicate the need for a sufficient observation period in road reclamation studies.
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Affiliation(s)
- Oili Tarvainen
- Natural Resources Institute Finland, P.O. Box 413, FI-90014, Oulun yliopisto, Finland.
| | - Anne Tolvanen
- Natural Resources Institute Finland, P.O. Box 413, FI-90014, Oulun yliopisto, Finland
- Thule Institute, Oulu University, P.O. Box 7300, FI-90014, Oulun yliopisto, Finland
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Abstract
We present a framework for evaluating and communicating effects of human activity on water quality in managed forests. The framework is based on the following processes: atmospheric deposition, weathering, accumulation, recirculation and flux. Impairments to water quality are characterized in terms of their extent, longevity and frequency. Impacts are communicated using a "traffic lights" metaphor for characterizing severity of water quality impairments arising from forestry and other anthropogenic pressures. The most serious impairments to water quality in managed boreal forests include (i) forestry activities causing excessive sediment mobilization and extirpation of aquatic species and (ii) other anthropogenic pressures caused by long-range transport of mercury and acidifying pollutants. The framework and tool presented here can help evaluate, summarize and communicate the most important issues in circumstances where land management and other anthropogenic pressures combine to impair water quality and may also assist in implementing the "polluter pays" principle.
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Affiliation(s)
- Martyn N Futter
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden.
| | - Lars Högbom
- Skogforsk, Uppsala Science Park, 751 83, Uppsala, Sweden.
| | - Salar Valinia
- Norwegian Institute for Water Research, Gaustadalléen 21, 0349, Oslo, Norway.
| | - Ryan A Sponseller
- Department of Ecology and Environmental Science, Umeå University, 901 87, Umeå, Sweden.
| | - Hjalmar Laudon
- Department of Forest Ecology and Management, SLU, Skogsmarksgränd, 901 83, Umeå, Sweden.
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30
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Lundmark T, Bergh J, Nordin A, Fahlvik N, Poudel BC. Comparison of carbon balances between continuous-cover and clear-cut forestry in Sweden. Ambio 2016; 45 Suppl 2:203-13. [PMID: 26744054 PMCID: PMC4705068 DOI: 10.1007/s13280-015-0756-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Continuous-cover forestry (CCF) has been recognized for the production of multiple ecosystem services, and is seen as an alternative to clear-cut forestry (CF). Despite the increasing interest, it is still not well described how CCF would affect the carbon balance and the resulting climate benefit from the forest in relation to CF. This study compares carbon balances of CF and CCF, applied as two alternative land-use strategies for a heterogeneous Norway spruce (Picea abies) stand. We use a set of models to analyze the long-term effects of different forest management and wood use strategies in Sweden on carbon dioxide emissions and carbon stock changes. The results show that biomass growth and yield is more important than the choice of silvicultural system per se. When comparing CF and CCF assuming similar growth, extraction and product use, only minor differences in long-term climate benefit were found between the two principally different silvicultural systems.
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Affiliation(s)
- Tomas Lundmark
- Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, 901 86, Umeå, Sweden.
| | - Johan Bergh
- Department of Forestry and Wood Technology, Linnaeus University, 351 95, Växjö, Sweden.
| | - Annika Nordin
- Department of Forest Genetics and Plant Physiology, Umeå Plant Science Centre, Swedish University of Agricultural Sciences, 901 86, Umeå, Sweden.
| | - Nils Fahlvik
- Southern Swedish Forest Research Centre, Swedish University of Agricultural Sciences, 230 53, Alnarp, Sweden.
| | - Bishnu Chandra Poudel
- Department of Forestry and Wood Technology, Linnaeus University, 351 95, Växjö, Sweden.
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31
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Owojori OJ, Siciliano SD. The potentiation of zinc toxicity by soil moisture in a boreal forest ecosystem. Environ Toxicol Chem 2015; 34:600-607. [PMID: 25502519 DOI: 10.1002/etc.2846] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Revised: 12/02/2014] [Accepted: 12/03/2014] [Indexed: 06/04/2023]
Abstract
Northern boreal forests often experience forest dieback as a result of metal ore mining and smelting. The common solution is to lime the soil, which increases pH, reducing metal toxicity and encouraging recovery. In certain situations, however, such as in Flin Flon, Manitoba, Canada, liming has yielded only moderate benefits, with some locations responding well to liming and other locations not at all. In an effort to increase the effectiveness of the ecorestoration strategy, the authors investigated if these differences in liming responsiveness were linked to differences in toxicity. Toxicity of metal-impacted Flin Flon soils on the oribatid mite Oppia nitens and the collembolan Folsomia candida was assessed, with a view toward identifying the metal of concern in the area. The effects of moisture content on metal sorption, uptake, and toxicity to the invertebrates were also investigated. Toxicity tests with the invertebrates were conducted using either Flin Flon soils or artificial soils with moisture content adjusted to 30%, 45%, 60%, or 75% of the maximum water-holding capacity of the soil samples. The Relative to Cd Toxicity Model identified Zn as the metal of concern in the area, and this was confirmed using validation tests with field contaminated soils. Furthermore, increasing the moisture content in soils increased the amount of mobile Zn available for uptake with the ion exchange resin. Survival and reproduction of both invertebrates were reduced under Zn exposure as moisture level increased. Thus, moisture-collecting landforms, which are often also associated with high Zn concentrations at Flin Flon, have, as a result, higher Zn toxicity to the soil ecosystem because of increases in soil moisture.
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Affiliation(s)
- Olugbenga J Owojori
- Department of Soil Science, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Department of Zoology, Obafemi Awolowo University, Ile-Ife, Nigeria
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