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 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 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 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 Coarse Woody Debris Effects on Biogeochemistry in Two Reconstructed Soils in the Athabasca Oil Sands Region in Alberta Canada written by Jin-Hyeob Kwak and published by . This book was released on 2015 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: Forest floor mineral soil mix (FMM) and peat mineral soil mix (PMM) are cover soils commonly used for land reclamation post open pit oil sands mining in northern Alberta, Canada. While in such land reclamation practices the organic matter comes from the peat material salvaged before land disturbance, coarse woody debris (CWD) can be used as an additional organic matter amendment for land reclamation. Effects of cover soil type (FMM vs PMM) and CWD (near vs away from CWD) on microbial community level physiological profile, extracellular enzyme activities, greenhouse gas emission rates and nitrogen (N) transformation rates were determined between 4 and 7 years after reclamation to assess whether applying CWD can facilitate land reclamation. Soil sampling and analyses were conducted and greenhouse gas emission rates were measured monthly during growing seasons within 5 cm from CWD and more than 100 cm away from CWD. Monthly in situ soil incubation was conducted and plant root simulators were incubated to assess net N transformation rates and N supply rates, respectively. A laboratory incubation experiment using 15N isotopic dilution was conducted to evaluate the effect of CWD leachate on gross and net N transformation rates. The soil microbial community level physiological profile was changed by CWD in FMM (p

Download or read book Oil Shales and Tar Sands written by United States. Department of Energy and published by . This book was released on 1977 with total page 752 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Organic Matter Accumulation in Reclaimed Soils Beneath Different Vegetation Types in the Athabasca Oil Sands written by Jeff Anderson and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Assessing the Long term Impact of Acid Deposition and the Risk of Soil Acidification in Boreal Forests in the Athabasca Oil Sands Region in Alberta Canada written by Kangho Jung and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Canadian Wetland Classification System written by and published by . This book was released on 1987 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: A classification system for Canadian wetlands based on the collective expertise and research of scientists across Canada. The system is provisional and subject to revision in future editions.

Download or read book Metal Concentration in Plants and Soils in the Athabasca Oil Sands Region written by G. L. Lesko and published by . This book was released on 1990 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Pathways of Anaerobic Organic Matter Decomposition in Tundra Soils from Barrow Alaska written by and published by . This book was released on 2015 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic tundra soils store a large quantity of organic carbon that is susceptible to decomposition and release to the atmosphere as methane (CH4) and carbon dioxide (CO2) under a warming climate. Anaerobic processes that generate CH4 and CO2 remain unclear because previous studies have focused on aerobic decomposition pathways. To predict releases of CO2 and CH4 from tundra soils, it is necessary to identify pathways of soil organic matter decomposition under the anoxic conditions that are prevalent in Arctic ecosystems. Here molecular and spectroscopic techniques were used to monitor biological degradation of water-extractable organic carbon (WEOC) during anoxic incubation of tundra soils from a region of continuous permafrost in northern Alaska. Organic and mineral soils from the tundra active layer were incubated at -2, +4, or +8°C for up to 60 days to mimic the short-term thaw season. Results suggest that, under anoxic conditions, fermentation converted complex organic molecules into simple organic acids that were used in concomitant Fe-reduction and acetoclastic methanogenesis reactions. Nonaromatic compounds increased over time as WEOC increased. Organic acid metabolites initially accumulated in soils but were mostly depleted by day 60 because organic acids were consumed to produce Fe(II), CO2, and CH4. We conclude that fermentation of nonprotected organic matter facilitates methanogenesis and Fe reduction reactions, and that the proportion of organic acids consumed by methanogenesis increases relative to Fe reduction with increasing temperature. As a result, the decomposition pathways observed in this study are important to consider in numerical modeling of greenhouse gas production in the Arctic.

Download or read book Soil Capping Research in the Athabasca Oil Sands Region written by Lee Barbour and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Natural Regions and Subregions of Alberta written by David J. Downing and published by . This book was released on 2006-01-01 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: This document presents the climatic, physiographic, vegetation, soil, wildlife and land use attributes that characterize each natural region and subregion. It has been organized into four parts: part one outlines national region and subregion concepts, part two describes methods used to generate climate statistics, part three presents a comparative analysis of selected climate statistics to facilitate comparison of natural regions and subregions, and part four presents detailed climatic, vegetation, soils and physiographic descriptions for six natural regions and twenty-one natural subregions currently recognized in Alberta.

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 Soil Acidification by Emitted Sulphur in the Athabasca Oil Sands Area written by Paul Y. P. Yeung and published by . This book was released on 1980 with total page 137 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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.