Download or read book Environmental Controls on Carbon Sequestration in a Saline Boreal Peat forming Wetland in the Athabasca Oil Sands Region written by Olena Volik and published by . This book was released on 2018 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt: Saline boreal fens represent potential models for post-mining landscape reclamation in the Athabasca Oil Sands Region (AOSR) (Canada) where wetland construction is challenged by salinization. One of the key indicators of reclamation success is the accumulation of organic carbon within constructed fens, and a better understanding of the drivers of carbon sequestration in natural saline fens can be useful for advancing fen construction in this region. As such, this thesis aims to determine the main environmental controls on carbon uptake and its long-term storage in a saline boreal fen near Fort McMurray (Alberta, Canada) by: 1) reconstructing past salinity change; 2) determining relations between reconstructed salinity, hydrological conditions, vegetation and organic matter accumulation rates (OMAR) over the last ~100 years in open-water areas (ponds) within the fen; 3) investigating the effects of salinity, vegetation and hydrology on the long-term apparent rate of carbon accumulation (LARCA) within the peatland; and 4) assessing CO2 fluxes within the peatland and open-water areas. Past salinity change was investigated using paleolimnological analysis of sediment cores from three ponds situated within the fen. Salinity fluctuations were reconstructed using weighted-averaging transfer functions based on diatoms and an environmental dataset from 32 saline boreal ponds. Results reveal complex “precipitation - surface water - groundwater” interactions associated with differences in the hydrologic functioning of the studied ponds, and their connectivity with shallow groundwater aquifers and adjacent wetlands. Relationships between cumulative departure from mean precipitation (CDLM) and diatom-inferred (DI) salinity suggest that precipitation may control salinity both directly and indirectly. In ponds recharged predominantly by meteoric water, precipitation may govern salinity directly by dilution of salt content in water, so that increases in precipitation result in a salinity decline. In ponds situated within a saline groundwater discharge zone, salinity may be influenced by precipitation indirectly through recharge of the saline aquifer, so increases in precipitation lead to rises in salinity. Our study suggests that complex DI-salinity response to precipitation change, coupled with notable range of DI-salinity fluctuation within natural saline fens should be considered while designing saline constructed wetlands and predicting their potential resilience under climate change. Median OMAR (181 g m-2 yr-1) of the site suggests that ponds situated within saline boreal fens OMAR comparable to freshwater boreal and subarctic ponds, and reconstructed salinity levels (3-21 ppt) did not severely affect organic matter accumulation. Strong significant positive (Lager Pond), strong significant negative (South Pond), and weak insignificant (Pilsner Pond) correlations between OMAR and DI-salinity were observed, suggesting that relations between organic matter accumulation and salt content are not straightforward, and salinity was not the main control on OMAR. Macrofossil data showed that OM accumulation was mainly driven by water level, type of primary producers and pond regime. OMAR was the highest during the transition from peatland to ponds due to low decomposition rates resulting from high inputs of relatively resistant plant litter, and anoxic conditions. A macrophyte-dominated pond regime was associated with higher OMAR relative to phytoplankton-dominated regime. LARCA within the fen was studied using two peat sediment cores. Changes in LARCA in the less saline part of the fen correlate well with water table fluctuations and seem not to be affected by low salinity (EC 5 mScm-1). The highest LARCA values are related to wet conditions; however, prolonged inundations coupled with high salinity (EC10 mScm-1) appear to have negative effect on LARCA. In the southern more saline part of the fen relationships between LARCA and hydrology are complicated by salinity probably through the impact on the net primary productivity. The influence of salinity on LARCA is determined by salinity level, and there is a threshold value (probably 10 mScm-1) after which salinity can significantly affect “LARCA - hydrology” links. Mean LARCA of the site (19.7 gm-2 yr-1) is lower than in western continental fens, but it is comparable to the average rate reported for western Canadian peatlands. The northern less saline part of the fen has LARCA of 29.67 gm-2 yr-1 that is close to LARCA in rich fens, but LARCA in the southern part is considerably lower (9.79 gm-2yr-1). Environmental controls on net ecosystem exchange (NEE), ecosystem respiration (R), and gross primary productivity (GEP) within the fen were studied using community-scale CO2 measurements along a salinity gradient. Strong positive correlations between NEE, GEP, leaf area index (LAI), and vegetation biomass within terrestrial areas and strong positive correlation between GEP and vegetation density within aquatic areas illustrated importance of vegetation properties for carbon uptake. CO2 fluxes within peatland were driven primary by water table depth, and electrical conductivity as revealed by strong negative correlations between these variables and NEE, GEP, and R. Links between CO2 exchange and environmental factors were influenced by microtopographical differences, and additional controls (e.g., soil moisture, availability of magnesium, manganese and calcium) on NEE, GEP, and R were found within depressions. Strong negative correlation between R and water table depth (WTD), coupled with strong positive correlation between R and belowground biomass within ridges and no significant correlation between WTD and R within depressions possibly suggested predominance of root and/ or root-associated microbial respiration within depressions and prevalence of microbial respiration within ridges. Within open water areas, GEP and R were related to phosphate concentration as suggested by strong positive correlation. In contrast to terrestrial areas, EC had no relations to CO2 fluxes, and higher GEP was found in mesosaline ponds comparatively to hyposaline ones. This study revealed importance of development of appropriate planting schemes for terrestrial and open-water.

Download or read book Characterizing Controls on Plot scale Evapotranspiration and Soil Water Dynamics of a Constructed Fen in the Athabasca Oil Sands Region Alberta written by Sarah Scarlett and published by . This book was released on 2015 with total page 59 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the Athabasca oil sands region of the Western Boreal Plains (WBP) mining companies now recognize the importance of reclaiming peatlands, as they cover > 50% of the pre-mined regional landscape. Open-pit mining operations require the removal of overburden, which is the surficial soil and vegetation overlying the oil-bearing formation. As a result, mining processes leave an unnatural, undulating landscape, which promotes the establishment of ecosystems non-native to the region. To date, oil sands wetland reclamation efforts have focused on marsh and open water wetlands. However, these wetland systems are not abundant in the sub-humid climate of the WBP due to high evaporative demand from free water surfaces. Despite their abundance on the landscape, the re-establishment of peatland ecosystems had not been previously tested due to their complexity and long successional development. However, the importance of these ecosystems was recognized by Alberta's Environmental Protection and Enhancement Act (EPEA), which mandated mining companies to test peatland reclamation. As a result Suncor's Nikanotee Fen, an experimental fen and watershed constructed as part of the landscape reclamation, was completed in 2013 and engineered with the intent to support natural fen vegetation and hydrologic processes. During the initial years post-construction, the influence of the experimental planting design on the fen's hydrology is unknown. Therefore, plot-scale evapotranspiration (ET) and soil water dynamics were monitored at various mulched and unmulched vegetation plots (control, moss, seedlings; n = 31) across the fen, including ponds. Treatments types were found to influence available energy and thus ET, with highest rates over open water (4.4 mm/day) and lowest rates over moss-mulch plots (2.4 mm/day). Mulch reduced ET by lowering the vapour pressure deficit within the mulch layer, thus providing a favorable microclimate for moss establishment by elevating near-surface relative humidity and reducing air and soil temperatures by ~2°C. Plot-scale ET trends followed ponds (331 mm) > seedlings (294 mm) > seedling-mulch (273 mm) > control (246 mm) > moss (212 mm) > moss-mulch (179 mm), where cumulative seasonal ET exceeded cumulative precipitation (132 mm) in all plots. While plot type was found to influence ET losses, it did not show a significant control on soil water dynamics in this study. While there were slight water deficits (P-ET) and lower soil moisture contents in mulched plots, probably caused by precipitation interception, the specific effects of mulch on plot soil water dynamics are difficult to elucidate due to significant differences in plot water table levels (p 0.05). Water table variability was directly related to surface elevation, which differed between plots by ~ 24 cm. Despite a relatively small range in elevations, plot water table positions varied 20 cm bgs, where plots located at higher elevations had consistently lower and more variable water tables. Furthermore, the salvage and placement methods of the peat created highly heterogeneous peat properties across the fen, which significantly differed with location across the fen (p

Download or read book Response of Peatland Microbial Community Function to Contamination by Naphthenic Acids and Sodium in the Athabasca Oil Sands Region Alberta Canada written by Vinay Daté and published by . This book was released on 2016 with total page 91 pages. Available in PDF, EPUB and Kindle. Book excerpt: Reclamation of closed oil sands mining operations in former pristine boreal ecosystems of the Athabasca Oil Sands Region of Alberta, Canada (AOSR) requires construction of new fen land uses such as peatlands in order to meet the environmental regulatory requirements for restoration of 'equivalent landscape capacity' and because 'wetlands are required as an integral part of the reclaimed landscape' (Alberta Government 2000). Reconstruction rather than restoration is required due to the extensive disruption to the vegetation and hydrology of these sites inherent to the mining process. Such sites will be constructed with tailings sands forming part of the aquifer; consequently, they may be exposed through leaching to a variety of chemical contaminant species either not present (e.g. naphthenic acids) or present at significantly higher-than-baseline concentrations (Na+) than in the pre-disturbance sites. The presence of these contaminants is likely to affect both the plant and microbial communities, which are the two major players in the carbon cycling function of peatland landscapes, and the effects of these contaminants on the microbial community is unknown in such landscapes. Oil sands process-affected water (OSPW) contains high concentrations of the contaminants to which these sites might be exposed. This study therefore tested the effects of OSPW on the aerobic and anaerobic carbon-cycling potential activity of the microbial communities of a variety of reference peatlands from the AOSR to determine the possible effects these contaminants might have on the communities of these constructed sites, through measurement of substrate-induced respiration (SIR) and methanogenic potential respectively. This study also measured the baseline aerobic and anaerobic carbon-cycling potential of these sites, to provide a reference baseline against which site managers might measure the development of such sites. Aerobic carbon-cycling potential at the start of the growing season was not significantly different (p=0.799) between the hypersaline rich fen and the Sphagnum-dominated poor fen, which both had significantly greater aerobic carbon-cycling potential than the treed rich fen at the start of the growing season. The sites' aerobic carbon-cycling potential did not significantly differ between any pair of sites at midseason. The low potential of the treed rich fen was attributed to phosphorus limitation indicated by a substrate preference for low molecular-weight organic acids in that site. None of the sites displayed any significant change in overall SIR on exposure to OSPW, though the hypersaline site showed an SIR preference for saccharide compounds only under contamination, attributed to salt stress response from the high levels of Na+ present in OSPW. The overall lack of effect of OSPW contamination was likely either due to short incubation times (6h) or the immobilization of OSPW contaminants through physical and chemical interactions with the peat substrate. Control methanogenic potential was highest at the treed rich fen, significantly lower at the poor Sphagnum-dominated fen, and significantly lower than either of the other two sites at the hypersaline rich fen. The extremely low control methane of the hypersaline rich fen site was likely due to the presence of sulfate in the pore water of that site and inhibition of methanogenesis via the presence of a more thermodynamically favourable terminal electron acceptor. Exposure to OSPW significantly decreased methanogenic potential in both the treed rich fen and the hypersaline rich fen, but had no significant impact on methanogenic potential in the Sphagnum-dominated poor fen. As amendment with OSPW containing twice its usual concentration of Na+ did not significantly further decrease methanogenic potential, it appears unlikely that high sodium concentrations are responsible for the inhibitory effect. The mechanism of resistance to OSPW inhibition in the Sphagnum-dominated poor fen is also unclear, but may be the consequence of a more-resilient microbial community or the rapid consumption by the microbial community of any alternative electron acceptors that might be suppressing methanogenesis. These results have implications for the construction of site-reclamation peatlands. Identifying the mechanism of resistance to OSPW contamination of methanogenesis in Sphagnum peat will inform choices about its use in the construction of such sites.

Download or read book Dissolved Organic Carbon Production and Transport in a Constructed Watershed in the Athabasca Oil Sands Region Alberta written by Sarah Irvine and published by . This book was released on 2018 with total page 105 pages. Available in PDF, EPUB and Kindle. Book excerpt: Within the Western Boreal Plains, a significant amount of surface cover has been removed through open-pit oil sands mining activities, which includes fen peatlands. Fen construction has been performed on the post-oil sands mined landscape, with the goal of returning ecohydrologic function such that the fen may become a carbon sink. Early results from studies within the Nikanotee Fen watershed indicate that groundwater is directed from the upland towards the fen, which has become a carbon sink. Work within the carbon budget includes dissolved organic carbon (DOC), and early post-succession concentrations and quality have been compared to natural analogues within the region. It was determined that initial conditions do not resemble that of reference sites; DOC concentrations were lower at the constructed site, and DOC appeared large and aromatic. However, DOC quantity and quality may shift as vegetation becomes established on the fen. However, no work has been done to determine the importance of other DOC sources in relation to both DOC dynamics within the fen, and how all DOC sources interact to affect DOC export quantity and quality. DOC export is typically highest in wetland-dominated watersheds, and can have important impacts on nutrient cycling, metal mobility, acidity, and availability of organics downstream. Therefore, it is important to ascertain if vegetation has become an important DOC source, and to consider hydrologic sources of DOC as well. This will be important when determining the best strategies for fen integration into a larger landscape. For this research, DOC concentration, flux, and quality was assessed through all sources within the watershed, to determine the relative importance of each input for determining DOC export from the site. DOC concentration and quality within the fen was then compared to reference sites, to assess the evolution of DOC sources post-construction. Water sampling occurred from May-August, 2015 in and July-August in 2016. It was determined that hydrological fluxes represented minimal inputs to the fen compared to the net production from vegetation, specifically as root exudates. However, when compared to reference sites, the constructed fen displayed less variability in its sources of DOC, whereas natural analogues displayed characteristics of both vegetation and microbially-sourced DOC. This is unlikely to change until mosses become dominant on site, or peat accumulation occurs. When considering all hydrological sources of DOC, groundwater represented the largest in 2015, while precipitation was the largest input in 2016. DOC concentration from each input did not significantly vary seasonally or by event size, therefore DOC fluxes were dependent on the volume of water mobilised. Yet, DOC quality varied substantially between sources. Both 2015 and early 2016 received less than average precipitation, this limited groundwater recharge and runoff in 2015. In wetter years, hydrologic inputs would increase, however will still be considerably less than the net production within the fen. This is evident when analyzing DOC quality at the outflow; DOC quality most resembled that in the fen. Total DOC export was limited, due to dry conditions. As DOC export only occurs through surface flow, dry conditions limited surface runoff within the fen, also promoting DOC accumulation. It is unlikely that hydrologic inputs will increase enough to represent a significant portion of the DOC budget in the fen even in wet years, therefore when the outflow is situated adjacent to the fen, monitoring should be most intensive within the fen. However, in constructed watersheds that do not contain wetlands, it will be important to monitor each contributing area to determine which areas within the watershed represent important DOC fluxes downstream, and how the DOC quality from each source may impact downstream biogeochemical dynamics.

Download or read book Methane Dynamics of a Constructed Fen in the Athabasca Oil Sands Region Alberta written by Kimberley Murray and published by . This book was released on 2017 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oil sands mining activities in the Athabasca Oil Sands Region in northeastern Alberta, Canada have resulted in an extensive amount of land disturbance. The Alberta government requires some reclamation of disturbed land to be to wetland ecosystems, and given the predominance of fen peatlands in the area, fen construction on post-mined landscapes has recently been attempted. Peatlands sequester substantial amounts of carbon over thousands of years due to waterlogged conditions and inefficient decomposition, and on a large time scale provide a cooling effect on the planet's radiative budget. However, peatland conditions are also ideal for production of the strong greenhouse gas methane (CH4). Natural peatlands emit a significant amount of CH4 to the atmosphere, particularly following formation when these ecosystems have a net warming effect associated with the large CH4 flux. Given the knowledge that the conditions that are conducive to CH4 production and flux in natural peatlands also result in the eventual accumulation of peat and carbon sequestration, understanding the CH4 dynamics of constructed fens may indicate biogeochemical function, along with the ability of these ecosystems to ultimately accumulate peat, a major goal of reclamation. Further, understanding important controls on CH4 dynamics from the constructed fen, including vegetation and geochemistry, in comparison to natural sites, is beneficial for the development of recommendation that may result in lower CH4 flux through vegetation impacts, but appropriate water chemistry for peat accumulation. For this research CH4 flux, CH4 concentration, and variables including vegetation and hydrochemistry were monitored from a constructed fen and two natural reference sites in northeastern Alberta over the 2015 growing season. A factorial greenhouse experiment was also used to understand differences in CH4 flux, concentration, and oxidation between two vascular plants, Carex aquatilis and Juncus balticus, planted for fen construction. This greenhouse experiment further considered how water sourced from the reclaimed constructed fen influenced CH4 dynamics compared to natural rich fen water. Both the field data from 2015 and the greenhouse experiment results found lower CH4 concentration from constructed fen plots compared to natural fen plots. Differences in hydrochemistry/water chemistry variables were found between constructed fen and natural fen plots in both studies, including evidence of terminal electron acceptors known to influence CH4 production such as sulfur, iron, manganese, and inorganic forms of nitrogen. While aboveground biomass and productivity in the field was found to be similar or higher at the constructed fen site compared to the two reference sites, belowground biomass was lower. In the greenhouse experiment, on the other hand, above and belowground biomass and productivity was similar between Carex aquatilis and Juncus balticus plots. Overall, several vegetation and hydrochemistry/water chemistry variables were found to significantly explain the CH4 results in the field and greenhouse experiment. For example, in both cases high sulfur at the constructed fen plots decreased CH4 flux and concentration. Lower CH4 concentration and higher relative oxidation found from plots including Juncus balticus compared to Carex aquatilis in the greenhouse experiment suggest that planting Juncus balticus in future constructed fen projects may result in lower CH4 flux. However, CH4 emissions will likely remain low at constructed fens if water chemistry does not change over time, or if future constructed fen designs are not altered to result in water chemistry more similar to natural sites.

Download or read book Restoration and Reclamation of Boreal Ecosystems written by Dale Vitt and published by Cambridge University Press. This book was released on 2012-09-20 with total page 427 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides the conceptual backbone and specific information necessary for the ecologically sound restoration and sustainable development of boreal ecosystems.

Download or read book Boreal Peatland Ecosystems written by R.K. Wieder and published by Springer Science & Business Media. This book was released on 2006-10-16 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is the first truly ecosystem-oriented book on peatlands. It adopts an ecosystems approach to understanding the world's boreal peatlands. The focus is on biogeochemical patterns and processes, production, decomposition, and peat accumulation, and it provides additional information on animal and fungal diversity. A recurring theme is the legacy of boreal peatlands as impressive accumulators of carbon as peat over millennia.

Download or read book Baseline Hydrogeochemistry and Connectivity Among Landscape Units of Two Wetland rich Boreal Sites in the Athabasca Oil Sands Region Alberta written by Caren Küsel and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Developing critical loads for nitrogen (N) in the Athabasca Oil Sands Region (AOSR) requires an understanding of the hydrological connectivity and potential for N transport among uplands, fens and bogs typical in the wetland-rich Boreal region of northern Alberta. The Cumulative Environmental Management Association's (CEMA) overarching mandate is to determine a nitrogen critical load specific to the Boreal region of northern Alberta. To this end, nitrogen amendment experiments were initiated at two Boreal wetland sites: an upland -- rich fen gradient at Jack Pine High (JPH) and an upland -- fen -- bog mosaic at Mariana Lakes (ML), 45 km north and 100 km south of Fort McMurray respectively.The objectives of this study are to use geochemical and isotopic tracers to describe baseline hydrogeochemical variability and connectivity between bog, fens and upland areas in the AOSR. Sites were instrumented with piezometer nests and water table wells along transects that cover the targeted landscape units (n = 108 sampling locations). Fieldwork related to this thesis was conducted during the open-water season: in June and August 2011, and in May, July, and September 2012. Field campaigns also included a snow survey (March 2012), and spring melt/freshet sampling (April 2012). The analysis of spatiotemporal variability of water isotopes and geochemistry in the years 2011-2012 yielded: i) a characterization of baseline conditions from which perturbations can be assessed, and ii) evidence of connectivity among landscape units. No evidence for elevated concentrations of nitrogen related to the amendment experiments was found in 2011 or 2012. The baseline characterization and annual monitoring did show increasing concentrations of inorganic ammonium with increasing depth associated with increasing solute concentrations: average concentrations of inorganic ammonium were 23 mg/L at deepest sampling locations (7 m) at ML bog and ML fen landscape units. These ammonium concentrations in porewaters, given a porosity of 0.90 for peatlands, constitute a store of ammonium that may be a significant source of nitrogen if the hydrology is altered due to co-occurring changes in vegetation (due to, for example, elevated nitrogen inputs), climate and/or landuse.Hydrologic connectivity at JPH is likely driven by topography. Hydraulic head in 2011 and 2012 field seasons showed that flow persisted from the upland to the fen. The consistent and distinct geochemical signatures and isotopic labelling of mid-depth and deep groundwater samples of fen and upland landscape units is consistent with such a stable groundwater continuum. Near-surface water samples at JPH fen however varied hydrogeochemically in response to seasonal changes in precipitation inputs, water levels, and biogeochemical productivity ... .

Download or read book Mires written by Anthony John Poynter Gore and published by . This book was released on 1977 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Limnogeology Progress Challenges and Opportunities written by Michael R. Rosen and published by Springer Nature. This book was released on 2021-04-24 with total page 592 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book honors the career of Professor Elizabeth Gierlowski-Kordesch who was a pioneer and leader in the field of limnogeology since the 1980s. Her work was instrumental in guiding students and professionals in the field until her untimely death in 2016. This collection of chapters was written by her colleagues and students and recognize the important role that Professor Gierlowski-Kordesch had in advancing the field of limnogeology. The chapters show the breadth of her reach as these have been contributed from virtually every continent. This book will be a primary reference for scientists, professionals and graduate students who are interested in the latest advances in limnogeologic processes and basin descriptions in North and South America, Europe, Africa, and China. *Free supplementary material available online for chapters 3,11,12 and 13. Access by searching for the book on link.springer.com

Download or read book Water Quality of the Athabasca Oil Sands Area Vol 1 Data Collection and Quality written by Canada-Alberta. Alberta Oil Sands Environmental Research Program and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biogeochemical Controls on Carbon Fluxes in a Restored Coastal Freshwater Forested Wetland written by Mary Jane Carmichael and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: From a climate change perspective, one of the most important ecosystem services that wetlands provide is carbon sequestration, a regulating service that helps moderate the impact of increased anthropogenic and natural emissions of greenhouse gases like CO2 and CH4. Carbon dynamics in wetlands are influenced by processes that promote the accumulation of carbon in sinks and those that govern the release of carbon (e.g. act as carbon sources). The research described here evaluates the role of vegetation in carbon source/sink dynamics in a restored coastal freshwater forested wetland. Taxodium distichum (L.) Rich (bad cypress) represent a foundational species in coastal freshwater wetlands. These long-lived canopy dominants are well-adapted to flooded freshwater conditions, but particularly sensitive to changes in water chemistry associated with salinity incursion, an increasingly common situation in coastal regions of the southeastern United States. Chapters II and III investigate the impact of salinity incursion events on the ability of bald cypress to sequester carbon. I apply traditional techniques within the discipline of physiological plant ecology to a restoration setting to develop a baseline data set for the long-term evaluation and monitoring of restoration efforts at the Timberlake Observatory for Wetland Restoration. These data indicate that salinity incursion represents a long-term threat to the species ecophysiology, hence the success of the restoration effort currently underway. In addition to functioning as an important carbon sink, wetlands also represent the largest source of the annual flux of methane to the atmosphere. Vegetated wetland ecosystems in particular are hot spots of methane emissions. In Chapter IV, I provide the first comprehensive assessment of the importance of vegetation to the annual flux of methane to the atmosphere. In Chapters V and VI, I work towards identifying standing dead trees as a novel pathway in the annual flux of methane to the atmosphere from wetland ecosystems. Because of the substantial role that carbon gases play in greenhouse effects on global climate change, a greater resolution of the anthropogenic and biologic forces that control the source/sink dynamics of carbon in wetlands is important as society works towards mitigating current and future global warming.

Download or read book Organic Matter Decomposition at a Constructed Fen in the Athabasca Oil Sands Region in Alberta Canada written by Matthew Coulas and published by . This book was released on 2019 with total page 115 pages. Available in PDF, EPUB and Kindle. Book excerpt: Resource mining and extraction in northern Alberta has resulted in substantial disturbances across a variety of ecosystems, including fen peatlands. Provincial regulations require companies to reclaim disturbed areas to their pre-existing function, with fen reclamation only being attempted in recent years. Fen peatlands store tremendous amounts of carbon (C) due to organic matter accumulation exceeding decomposition. Due to the length of time required for the development of these landscapes it is imperative to identify potential opportunities to minimize decomposition, thereby maximizing peat accumulation. To meet this objective, sufficient understanding of the biogeochemical and environmental controls of organic matter (OM) degradation is a priority. This research estimates decomposition rate using the litter bag method and tea bag index at a constructed fen (Nikanotee fen) in the Athabasca Oil Sands Region (AOSR) near Fort McMurray, Alberta. Throughout the growing season in 2017, environmental conditions including volumetric water content (VWC), electrical conductivity (EC), pH, and soil temperature were measured to determine controls on decomposition. Additionally, soil and water samples were collected to determine biogeochemical controls on decomposition, namely phenolic compound concentration and extracellular enzyme activities. Laboratory incubations under oxic and anoxic conditions were also used to determine microbial respiration rates under varying treatments of peat, Carex aquatilis, Juncus balticus, straw, and wood-strand mulch, which (with the exception of straw) were all utilized in the construction of the Nikanotee fen. Mixed results were obtained from these two studies. Our field study suggests that Carex aquatilis biomass decomposes faster than Juncus balticus, and that decomposition is higher under plots planted with Carex aquatilis as opposed to Juncus balticus or left bare. Furthermore, we did not observe increased concentration of phenolics as a result of the wood-strand mulch, nor did we observe any significant evidence to support the enzymatic latch hypothesis at the constructed fen. Although we observed an inhibitory effect of phenolics on OM-degrading hydrolase enzymes at the reference sites, it was not observed at the constructed fen, nor was there a significant correlation between phenol oxidase (PO) activity and decomposition rate. Lastly, we found increased decomposition under higher pH, higher soil temperature, lower VWC and lower EC. Contrary to our field study, our laboratory findings suggest Juncus balticus may be of higher lability relative to the other treatments including Carex aquatilis. We also observed negative priming rates under oxic conditions from treatments containing Juncus balticus, while positive priming effects under anoxic conditions were observed from the Carex aquatilis treatments, which could significantly impact long-term C sequestration. Similar to the findings from our field study, our results from our laboratory incubation do not support the enzymatic latch theory. Phenolics were not readily leached from the wood-strand mulch, and we observed a negative interaction between PO activity and microbial respiration. Despite this, wood-strand mulch remains preferable over straw during fen reclamation due to its reduced lability and potential negative priming effect under anoxic conditions; however, if not required for successful vegetation establishment, wood-strand mulch is not a recommend amendment as it has little effect on decomposition rates.

Download or read book Water Quality of the Athabasca Oil Sands Area written by Akena, Anthony Mark and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Quality of the Athabasca Oil Sands Area a Regional Study written by Canada-Alberta. Alberta Oil Sands Environmental Research Program and published by . This book was released on 1985 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Quality of the Athabasca Oil Sands Area Volume 4 an Interim Compilation of Non AOSERP Water Quality Data written by Canada-Alberta. Alberta Oil Sands Environmental Research Program and published by . This book was released on 1981 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Water Quality of the Athabasca Oil Sands Area Vol 1 Data Collection Andquality Vol 4 an Interim Compilation of Non Aoserp Water Quality Data Project Ws 1 2 1 written by Alberta Oil Sands Environmental Research Program and published by . This book was released on 1980 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: