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Spatial Variability And Seasonal Dynamics Of Dissolved Organic Matter In Surface And Soil Pore Waters In Mire Forest Landscapes In The Komi Republic Northwest Russia
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Book Synopsis Spatial Variability and Seasonal Dynamics of Dissolved Organic Matter in Surface and Soil Pore Waters in Mire-forest Landscapes in the Komi Republic, Northwest-Russia by : Armine Avagyan
Download or read book Spatial Variability and Seasonal Dynamics of Dissolved Organic Matter in Surface and Soil Pore Waters in Mire-forest Landscapes in the Komi Republic, Northwest-Russia written by Armine Avagyan and published by . This book was released on 2013 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Seasonal and Spatial Variation in the Chemical Character of Dissolved Organic Matter Within a Small Boreal Forest Watershed by : Alexander W. Newman
Download or read book Seasonal and Spatial Variation in the Chemical Character of Dissolved Organic Matter Within a Small Boreal Forest Watershed written by Alexander W. Newman and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dissolved organic matter (DOM) is a significant carbon reservoir and component of the terrestrial-to-aquatic flux (Qualls et al., 1991). The terrestrial-to-aquatic carbon flux, a relatively new addition to global carbon models, is currently estimated to transfer a total of 1.7 petagrams (Pg) carbon (C) yr−1 globally (IPCC, 2013). Terrestrially derived DOM has been identified as a significant pool of organic matter in the aquatic environment. However, the quantity and chemical composition of DOM transferred, as well as the mechanisms driving its transfer, are less understood. This thesis focuses on expanding our knowledge of the processing DOM undergoes as it is transferred from terrestrial-to-aquatic environments by: 1) developing a standardized extraction methodology that can yield representative eluates when applied to sourced samples from throughout the terrestrial-to-aquatic interface and 2) applying the designed methodology to conduct a year long study of DOM quantity and composition in the terrestrial-to-aquatic interface in a boreal forest watershed. Experimental results suggest that although solid phase extraction with a divinyl benzene sorbent (SPE-PPL) yields high extraction efficiencies when applied to DOM, it is subject to selectivity. Extractions performed at high loading volumes were found to select against O-alkyl DOM hydrogen constituents, additionally all SPE-PPL experiments were found to select against nitrogenous DOM components. However, by considering proper extraction parameters, SPE-PPL can produce bulk representative eluates for nuclear magnetic resonance (NMR) analysis from land positions spanning the terrestrial-to-aquatic interface. Results from the field study revealed that DOM transferred from terrestrial-to-aquatic land positions in a boreal forest watershed is both temporally and regionally variable, however, proximity immediately downstream of ponds appeared to be a major hydrologic control, while seasonal variation in hydrologic flow paths may represent another control in boreal forest watersheds. Dissolved organic matter chemical composition and quantity in traditional boreal forest streams related to shifts in the hydraulic flow path of the watershed, indicated by changes in riverine DOM chemical composition that correlated to seasonal wet and dry periods. Increases in both dissolved organic carbon (DOC) concentration and the presence of O-alkyl DOM hydrogen functionalities in the stream indicated a shift from groundwater sources during the dry period to soil water sources during the wet period. Conversely streams downslope of ponds seemed to be buffered against shifts in DOM chemical composition associated with changes in hydrologic flow paths. Dissolved organic matter chemical composition of streams downslope of ponds were relatively constant throughout the year resembling the characterization of pond outflows, even during periods of high hydraulic conductivity, via additions of autochthonous DOM produced in the pond. These additions of autochthonous DOM are negligible in streams not downslope of ponds. Further application of this approach during key periods of DOM export, such as spring snowmelt and fall rain periods may prove help to reveal the processes controlling the terrestrial-to-aquatic carbon flux in boreal forest landscapes.
Book Synopsis Seasonal Dynamics of Organic Matter and Inorganic Nitrogen in Surface Waters of Alaskan Arctic Streams and Rivers by : Matthew Solomon Khosh
Download or read book Seasonal Dynamics of Organic Matter and Inorganic Nitrogen in Surface Waters of Alaskan Arctic Streams and Rivers written by Matthew Solomon Khosh and published by . This book was released on 2015 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate-linked changes in hydrology and biogeochemical processes within Arctic watersheds are likely already affecting fluvial export of waterborne materials, including organic matter (OM) and dissolved inorganic nitrogen (DIN). Our understanding of Arctic watershed OM and DIN export response to climate change is hampered by a lack of contemporary baselines, as well as a dearth of seasonally comprehensive studies. This work focuses on characterizing OM and DIN concentrations and sources in six streams/rivers on the North Slope of Alaska during the entirety of the hydrologic year (May through October) in 2009 and 2010. The highest OM concentrations occurred during spring snowmelt, with results indicating that terrestrial vegetation leachates are the major source of dissolved OM, while particulate OM originates from a degraded soil source. Over the hydrologic year, soils became a progressively increasing source of dissolved OM, while autochthonous production made up a sizeable proportion of particulate OM during base flow conditions. DIN concentrations were low throughout the spring and summer and increased markedly during the late summer and fall. Our findings suggest that penetration of water into thawed mineral soils, and a reduction in nitrogen assimilation relative to remineralization, may increase DIN export from Arctic watersheds during the late summer and fall. Although recent studies of Arctic rivers have emphasized the importance of the spring thaw period on OM export, our understanding of the mechanisms that control water chemistry observations during this time are still lacking. Experimental leaching results, from experiments conducted in 2014, suggest that aboveground plant biomass is a major source of dissolved OM in Arctic catchments during the spring, and that the timing of freezing and drying conditions during the fall may impact dissolved OM leaching dynamics on that same material the following snowmelt. Improved knowledge of OM and DIN temporal trends and the mechanisms that control seasonal concentrations is essential for understanding export dynamics of these water constituents in Arctic river systems. Perhaps more importantly, increased understanding of the seasonal controls on OM and DIN export in Arctic rivers is critical for predicting how these systems will respond under future climate change scenarios.
Book Synopsis Dissolved Organic Matter in Arctic Watersheds and Coastal Waters by : Craig Thomas Connolly
Download or read book Dissolved Organic Matter in Arctic Watersheds and Coastal Waters written by Craig Thomas Connolly and published by . This book was released on 2019 with total page 300 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic warming is already affecting the movement of freshwater and dissolved organic matter (DOM) from watersheds to the coastal ocean in the Arctic. Improved understanding of DOM in freshwater sources and linkages to DOM characteristics in Arctic coastal waters is needed to assess responses to and feedbacks with climate change. This work focuses on DOM characteristics that couple watershed and coastal systems in the Arctic, with specific considerations of river and groundwater inputs to lagoon ecosystems along the eastern Alaska Beaufort Sea coast. We found that spring and summer river-borne concentrations of dissolved organic carbon and nitrogen (DOC and DON) are strongly linked to variations in watershed slope and soil organic matter coverage across space and scale in the Arctic. The quantities and composition of DOM in lagoons of the eastern Alaska Beaufort Sea coast vary markedly between seasons. Specifically, lagoons experience a shift from high to low DOC and DON concentrations between the late spring sea ice break-up and winter ice-covered periods, but these concentrations are more variable during the summer open water period. Distinct seasonal transitions in ice coverage, runoff from land, and water exchange with the Beaufort Sea strongly influence the availability of lagoon DOM. During the summer, concentrations of DOC and DON in supra-permafrost groundwater (SPGW) inputs to lagoons are much higher than those found in local rivers and lagoons. Late-summer fluxes of SPGW DOM to the northern Alaska coastline are substantial and may be the principal source of DOM to lagoons without river inputs. This SPGW DOM is sourced from readily leachable organic matter in surface soils and deeper soil horizons that likely extend into thawing permafrost. SPGW DOM contains aromatic carbon compounds that are largely resistant to microbial degradation on the order of days to months. While nearby river and lagoon water DOM has a similar composition and degradability, SPGW contains a portion of bioavailable and reactive DOM that is not present in river and lagoon waters. Inputs of SPGW DOM provide a potentially important source of energy for lagoon food webs along the Alaskan Beaufort Sea coast during the late summer
Book Synopsis Dissolved Organic Matter Discharge in the Six Largest Arctic Rivers-chemical Composition and Seasonal Variability by : Amanda J. Rinehart
Download or read book Dissolved Organic Matter Discharge in the Six Largest Arctic Rivers-chemical Composition and Seasonal Variability written by Amanda J. Rinehart and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The vulnerability of the Arctic to climate change has been realized due to disproportionately large increases in surface air temperatures which are not uniformly distributed over the seasonal cycle. Effects of this temperature shift are widespread in the Arctic but likely include changes to the hydrological cycle and permafrost thaw, which have implications for the mobilization of organic carbon into rivers. The focus of this research was to describe the seasonal variability of the chemical composition of dissolved organic matter (DOM) in the six largest Arctic rivers (Yukon, Mackenzie, Ob, Yenisei, Lena and Kolyma) using optical properties (UV-Vis Absorbance and Fluorescence) and lignin phenol analysis. We also investigated differences between rivers and how watershed characteristics influence DOM composition. Dissolved organic carbon (DOC) concentrations followed the hydrograph with highest concentrations measured during peak river flow. The chemical composition of peak-flow DOM indicates a dominance of freshly leached material with elevated aromaticity, larger molecular weight, and elevated lignin yields relative to base-flow DOM. During peak flow, soils in the watershed are still frozen and snowmelt water follows a lateral flow path to the river channels. As the soils thaw, surface water penetrates deeper into the soil horizons leading to lower DOC concentrations and likely altered composition of DOM due to sorption and microbial degradation processes. The six rivers studied here shared a similar seasonal pattern and chemical composition. There were, however, large differences between rivers in terms of total carbon discharge reflecting the differences in watershed characteristics such as climate, catchment size, river discharge, soil types, and permafrost distribution. The large rivers (Lena, Yenisei), with a greater proportion of permafrost, exported the greatest amount of carbon. The Kolyma and Mackenzie exported the smallest amount of carbon annually, however, the discharge weighted mean DOC concentration was almost 2-fold higher in the Kolyma, again, indicating the importance of continuous permafrost. The quality and quantity of DOM mobilized into Arctic rivers appears to depend on the relative importance of surface run-off and extent of soil percolation. The relative importance of these is ultimately determined by watershed characteristics.
Book Synopsis Dissolved Organic Matter (DOM) by : Oleg S. Pokrovsky
Download or read book Dissolved Organic Matter (DOM) written by Oleg S. Pokrovsky and published by Nova Science Publishers. This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dissolved Organic Matter (DOM) is a major factor controlling global biogeochemical cycles of carbon, macro- and micronutrients and toxic metals. It plays a pivotal role both in mobilisation (chemical weathering), transport (organic complexes and colloids), biological uptake and deposition (microbial and photo-degradation) of a number of essential macro- (C, N, P) and micro- (Fe, Zn, Mn, Ni, Cu Co) nutrients. The interest of scientists to DOM is rapidly increasing. Between 1950 and 2017, more than 30,000 scientific papers on DOM were published (Web of Science® All Database Search); however, more than half of them were produced over the past nine years and over the last two and a half years, more than 5,400 papers were published. Such attention to DOM is clearly motivated by a combination of global climate change issues and the main role of DOM in CO2 exchange between the atmosphere and the surface waters. Despite such a large range of scientific problems concerning DOM properties, origins, and applications, there is a very strong geographical bias in terms of the amount of research devoted to various geographical regions of the world. The majority of information concerns temperate zones and boreal regions of Scandinavia and Northern America, with very little information available on Siberia and Russia. Thus, among the less than 30,000 scientific articles devoted to various aspects of DOM since 1950, only 150-200 of them are devoted to DOM in Russia or Siberia. This book is essentially oriented towards filling these gaps of our knowledge. Among thirteen chapters, eleven of them are devoted to various aspects of DOM in Russia and Siberia. Another important and still poorly characterised aspect of natural DOM is its colloidal status: four chapters of this book deal with the colloidal speciation of DOM in rivers and lakes. Given the breadth of physico-chemical, geochemical, biological, and geographical aspects of DOM covered in this book, it will be useful for a large audience of environmental scientists, limnologists, physico-chemists, soil and landscape scientists and biogeochemists.
Book Synopsis Seasonal Variability of Dissolved Organic Matter in the Columbia River by : Urban Wünsch
Download or read book Seasonal Variability of Dissolved Organic Matter in the Columbia River written by Urban Wünsch and published by . This book was released on 2014 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Dissolved Organic Matter Dynamics in an Arctic Catchment by : Kristin Eulene Judd
Download or read book Dissolved Organic Matter Dynamics in an Arctic Catchment written by Kristin Eulene Judd and published by . This book was released on 2004 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Resolving Spatial and Temporal Variability in Dissolved Organic Matter Characteristics Within Combined Agricultural and Stormwater Conveyances by : Bryce A. Mihalevich
Download or read book Resolving Spatial and Temporal Variability in Dissolved Organic Matter Characteristics Within Combined Agricultural and Stormwater Conveyances written by Bryce A. Mihalevich and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In many urban areas, stormwater runoff can threaten the ecological health of streams and downstream water bodies. Due to the increased impervious nature of urban landscapes, runoff is more 0́−flashy0́+ and as a result, high concentrations of pollutants can be transported in shorter periods of time than in more natural environments. One pollutant of concern is dissolved organic matter (DOM). DOM is important within aquatic ecosystems, but excess amounts can cause depletion in dissolved oxygen concentrations and can negatively affect aquatic organisms. This study investigated changes in DOM quantity and sources within the Northwest Field Canal (NWFC), an urban water conveyance located in Logan, Utah, USA that receives runoff during storm events. DOM was monitored at upstream and downstream locations within the canal and at selected stormwater outfalls within the study reach. During storm events, DOM concentrations were rapidly elevated to values orders of magnitude greater than in baseflow measurements, and were greater at the downstream site than at the upstream site, triggered by contributions from outfalls discharging into the canal. Changes in DOM composition during storm events confirmed that DOM is more terrestrially derived, whereas it is normally more microbially derived during baseflow conditions in the canal. These results provide better understanding of the composition of DOM in the canal system and may provide crucial information for future management of stormwater runoff that can potentially lead to the improvements of water quality in downstream water bodies.
Book Synopsis Seasonal and Spatial Variations in Dissolved Organic Matter Bioavailability and Nutrient Yields in Agricultural Streams by : Martha Mason Griffith
Download or read book Seasonal and Spatial Variations in Dissolved Organic Matter Bioavailability and Nutrient Yields in Agricultural Streams written by Martha Mason Griffith and published by . This book was released on 2008 with total page 214 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Does Dissolved Organic Matter Impact Primary Production? A Study on the Effects of Terrestrially Derived Dissolved Organic Matter on Primary Production in Nutrient-poor Boreal Lakes by : Bryanna Sherbo
Download or read book Does Dissolved Organic Matter Impact Primary Production? A Study on the Effects of Terrestrially Derived Dissolved Organic Matter on Primary Production in Nutrient-poor Boreal Lakes written by Bryanna Sherbo and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past few decades, spatial and temporal variation in concentrations of allochthonous dissolved organic carbon (DOC) has been increasing in surface waters of boreal lakes around the world with climate change. Terrestrial landscapes export large amounts of organic matter into lakes, primarily as DOC. It is understood that DOC impacts primary production through its combined effects on light and nutrient availability. However, there remains uncertainty as to the mechanisms that cause DOC to have positive or negative effects on algal productivity. In a survey of 6-7 lakes spanning a DOC gradient (3.5-9.4 mg L-1) at International Institute of Sustainable Development-Experimental Lakes Area (IISD-ELA) in northwestern Ontario, we determined the effects of DOC on whole-lake metabolism (gross primary production (GPP), respiration, and net ecosystem production (NEP)) and depth integrated net primary production (NPP). Using in situ diel free-water oxygen method and in vitro partial pressure of CO2 incubations, we found that primary production was significantly impacted by DOC. In general, the effects of DOC on algal productivity was negative, although there was some evidence for the stimulation of whole ecosystem production by nutrients at low DOC concentrations. Epilimnetic chlorophyll, GPP, and community respiration increased significantly with DOC, and total depth integrated and sub-epilimnetic NPP decreased significantly with DOC. Lakes with the highest proportion of sub-epilimnetic production had well developed deep chlorophyll maxima (DCM). DCM were negatively correlated with DOC and are viewed as ecological hotspots for higher trophic levels. DCM and sub-epilimnetic productivity were eliminated in lakes with DOC values > 7.1 mg L-1. These results substantiate the influence of allochthonous DOC on aquatic food webs and highlight the combined effects of DOC on light and nutrient availability. The association of DOC with epilimnetic nutrients caused an increase in epilimnetic GPP (chapter 2) and decreasing light availability caused a decrease in total and sub-epilimnetic NPP (chapter 3). These contrasting effects of DOC on primary production provide further insight into the balance between nutrients and light with increasing concentrations of DOC.
Book Synopsis Dissolved Organic Matter (DOM) Concentrations and Quality for Watershed Compartments in a Forested Mid-Atlantic Watershed, USA by : Nina Finger
Download or read book Dissolved Organic Matter (DOM) Concentrations and Quality for Watershed Compartments in a Forested Mid-Atlantic Watershed, USA written by Nina Finger and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: While the importance of dissolved organic matter (DOM) constituents is well recognized we know very little about how these constituents vary across watershed compartments, influence the transport of dissolved organic carbon (DOC) and nitrogen (DON), and determine the mobility and bioavailability of DOM. We explore the concentrations and quality of DOM for ten watershed sources in a 12 ha forested catchment over a two-year period. DOM was evaluated for throughfall, litter leachate, soil water, shallow and deep groundwater, groundwater discharged from seeps, stream water and water in the hyporheic zone. Soil water samples included both free flowing soil water (using zero tension lysimeters) as well as soil pore water (using tension lysimeters). DOM quality was characterized using a suite of indices derived from UV-visible absorbance and parallel factor analysis (PARAFAC) modeling of fluorescence excitation-emission matrices (EEMs). DOM quality displayed a pronounced trend in watershed compartments especially as a function of soil depth. The humic, aromatic, and high molecular weight constituents of DOM decreased with soil depth while there was a concomitant percent increase in the protein-like DOM moieties. Principal component analyses (PCA) revealed that the differences in surficial watershed compartments were dictated by humic components while differences in groundwater sources were dictated by % total proteins. The increase in % total proteins with increasing soil depth indicated that in groundwater a greater fraction of DOM may be bioavailable compared to DOM in litter leachate and soil water. We did not find any conclusive evidence for C or N enrichment in any particular DOM quality pools. In addition, DOM quality displayed pronounced spatial differences. DOM in wetland groundwater was more aromatic and humic than that at the riparian location. This study also suggested that some spectrofluorometric indices (e.g. the humification index, HIX) may be preferable over others (e.g. specific UV absorbance, SUVA) for characterizing DOM quality.
Author :P. M. Wallis Publisher :Canada. Inland Waters Directorate, Water Quality Branch ISBN 13 : Total Pages :68 pages Book Rating :4.3/5 (121 download)
Book Synopsis Sources, Transportation, and Utilization of Dissolved Organic Matter in Groundwater and Streams by : P. M. Wallis
Download or read book Sources, Transportation, and Utilization of Dissolved Organic Matter in Groundwater and Streams written by P. M. Wallis and published by Canada. Inland Waters Directorate, Water Quality Branch. This book was released on 1979 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: "It has long been recognized that streams in their natural state support a great deal more biomass than can be justified by primary production. This is believed to be the result of energy inputs to streams from terrestrial plants and animals which take the form of either Dissolved Organic Matter (DOM.45μ spherical diameter), or Particulate Organic Matter (POM.45μ)"--Introduction, page 1.
Book Synopsis Dynamics of Dissolved Organic Matter in Forest Ecosystems in Flanders by : Jeroen Vandenbruwane
Download or read book Dynamics of Dissolved Organic Matter in Forest Ecosystems in Flanders written by Jeroen Vandenbruwane and published by . This book was released on 2008 with total page 252 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Effects of Vegetation Control and Organic Matter Removal on Soil Water Content in a Young Douglas-fir Plantation by : Warren D. Devine
Download or read book Effects of Vegetation Control and Organic Matter Removal on Soil Water Content in a Young Douglas-fir Plantation written by Warren D. Devine and published by . This book was released on 2006 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Spatiotemporal Variability in Dissolved Organic Matter Composition and Its Relationship to Photochemical Reactivity by : Stephanie Berg (Ph.D.)
Download or read book Spatiotemporal Variability in Dissolved Organic Matter Composition and Its Relationship to Photochemical Reactivity written by Stephanie Berg (Ph.D.) and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dissolved organic matter (DOM) is a ubiquitous group of biologically derived organic molecules found in all natural waters. DOM makes up a substantial amount of the carbon stored in surface waters, and its original sources include allochthonous, or terrestrial, inputs as well as autochthonous, or aquatic, inputs. It is primarily made of up small (i.e.,
Book Synopsis Temporal and Spatial Variability in the Quality of Dissolved Organic Matter in Ocean Systems by : Stuart Jerome Goldberg
Download or read book Temporal and Spatial Variability in the Quality of Dissolved Organic Matter in Ocean Systems written by Stuart Jerome Goldberg and published by ProQuest. This book was released on 2008 with total page 312 pages. Available in PDF, EPUB and Kindle. Book excerpt: Oceanic DOM is an important substrate that fuels heterotrophic bacterial activity, however, there is a paucity of data regarding the composition and quality of DOM in ocean systems. I analyzed the total carbohydrate (TCHO) and dissolved combined neutral sugar (DCNS) fractions of dissolved organic carbon (DOC), and mainly used TCHO and DCNS yields (% of DOC) to assess DOM quality over large temporal and spatial scales throughout the ocean.
