Seasonal and Spatial Variations in Dissolved Organic Matter Bioavailability and Nutrient Yields in Agricultural Streams

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ISBN 13 :
Total Pages : 214 pages
Book Rating : 4.:/5 (31 download)

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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:

Seasonal and Spatial Variation in the Chemical Character of Dissolved Organic Matter Within a Small Boreal Forest Watershed

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (131 download)

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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.

Aquatic Organic Matter Fluorescence

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Publisher : Cambridge University Press
ISBN 13 : 0521764610
Total Pages : 407 pages
Book Rating : 4.5/5 (217 download)

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Book Synopsis Aquatic Organic Matter Fluorescence by : Paula G. Coble

Download or read book Aquatic Organic Matter Fluorescence written by Paula G. Coble and published by Cambridge University Press. This book was released on 2014-07-14 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: A core text on principles, laboratory/field methodologies, and data interpretation for fluorescence applications in aquatic science, for advanced students and researchers.

Decomposition of Dissolved Organic Matter in Arctic and Boreal Streams

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ISBN 13 :
Total Pages : 192 pages
Book Rating : 4.:/5 (986 download)

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Book Synopsis Decomposition of Dissolved Organic Matter in Arctic and Boreal Streams by : Audrey Mutschlecner

Download or read book Decomposition of Dissolved Organic Matter in Arctic and Boreal Streams written by Audrey Mutschlecner and published by . This book was released on 2017 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt: Arctic and boreal rivers connect terrestrial, oceanic, and atmospheric carbon (C) pools by transporting and processing dissolved organic matter (DOM). DOM composition influences its susceptibility to decomposition (biolability), which in turn determines whether the associated C is respired, stored, or exported. High-latitude ecosystems are changing rapidly due to processes such as permafrost thaw, shifts in vegetative communities, and increasing discharge, and each of these processes can influence the composition of DOM reaching rivers. The eventual fate of riverine DOM, whether it is mineralized or exported, shifts the balance of global C pools. Therefore, to understand how changes to high-latitude ecosystems influence the global C cycle, we must be able to connect patterns in DOM composition to its biolability and subsequent fate within the C cycle. The objectives of this study were to describe spatial and temporal patterns in DOM composition and biolability, and to determine links between the composition and biolability of DOM. I sampled DOM from streams along an Arctic-boreal gradient in interior Alaska throughout the year. I measured DOM biolability and nutrient limitation of decomposition in laboratory incubations and characterized DOM composition using optical properties and chemical analysis. I found that temporal patterns in DOM composition corresponded to seasonal trends in the hydrology of high-latitude catchments, linking DOM source to shallow, organic-rich flowpaths in spring and deeper groundwater flows in winter. Biolability was low, indicating that the majority of riverine DOM is recalcitrant to biological decomposition. I observed increased biolability in response to phosphorus (P) addition, particularly during spring, indicating that phosphorus limits DOM decomposition. To further examine the mechanisms driving C processing in streams, I also conducted a series of whole-stream experiments to compare the relative influence of molecular composition and nutrient content of DOM. I added leaf leachate to boreal streams and measured C retention, which represents both biological uptake and sorption. The leachates varied by molecular composition, due to differences in tissue chemistry of plant species, and in nutrient content, because the leaves were collected from plots with different fertilization regimes. Retention was greatest for leachates derived from trees that had been fertilized with P, indicating P-limitation of biological uptake of C or preferential sorption of P-containing organic molecules. Although leachates varied in molecular composition as determined by optical properties, these differences did not correspond to a difference in uptake rates by species. These patterns in DOM retention indicate that nutrient content is a greater constraint on C uptake than molecular composition. Together, the two studies suggest that export is the primary fate of ambient DOM in high-latitude streams, but that C processing is highly sensitive to inputs of bioavailable DOM. The coupling between the P and C cycles observed in both studies highlights the potential for nutrient availability to constrain or promote CO2 emissions from C-rich, high-latitude catchments.

Quantity and Composition of Stream Dissolved Organic Matter in the Watershed of Conesus Lake, New York

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ISBN 13 :
Total Pages : 116 pages
Book Rating : 4.:/5 (875 download)

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Book Synopsis Quantity and Composition of Stream Dissolved Organic Matter in the Watershed of Conesus Lake, New York by : Morgan Bida

Download or read book Quantity and Composition of Stream Dissolved Organic Matter in the Watershed of Conesus Lake, New York written by Morgan Bida and published by . This book was released on 2013 with total page 116 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The watershed of Conesus Lake, New York is drained by more than 18 unique streams and several smaller tributaries and has multiple land uses, varying from highly agricultural to primarily wooded, making the lake an ideal study site for analysis of the effects of land use on various water quality parameters. Previous water quality and watershed-health studies at Conesus Lake have focused on the delivery of inorganic nutrients to the lake. We know much less, however, about the effects of watershed land use on the quantity and composition of dissolved organic matter (DOM) exported to the lake. We sought to determine how stream DOM quantity and composition varied with space and time within the watershed during 2011. The concentrations of dissolved organic carbon and inorganic and organic nitrogen and phosphorus were measured seasonally in 7 streams, with a more detailed analysis of water chemistry in 12 streams during the growing season. The composition of DOM entering Conesus Lake was assessed with a suite of optical indices and with fluorescence excitation-emission matrices (EEMs) with parallel factor analysis (PARAFAC), a chemometric technique for the decomposition of characteristic fluorescence peaks. A 4-component PARAFAC model showed one allochthonous, humic-like component (C1), one semi-labile component with allochthonous and/or autochthonous origin (C2), and two autochthonous, protein-like components (C3 & C4). We showed seasonality in the composition and quantity of DOM that is consistent with abiotic seasonal controls and principal components analyses (PCA) suggest that agriculturally-dominated streams are associated with increased nitrate and phosphate, a greater proportion of protein-like PARAFAC components (C3 & C4), and that the DOM tends to be less humified. These results imply that a) seasonal controls on DOM govern the abundance of protein-like DOM and can alter the quantity of bulk DOM, b) agricultural land use may augment autochthonous production in a stream, particularly in the spring and summer, thus creating a more labile pool of DOM that is exported to the lake, and c) stream order can alter DOM quantity and composition, possibly through instream processing and variations in light availability."--Abstract.

Advances in the Physicochemical Characterization of Dissolved Organic Matter

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Publisher : ACS Symposium
ISBN 13 : 9780841229518
Total Pages : 0 pages
Book Rating : 4.2/5 (295 download)

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Book Synopsis Advances in the Physicochemical Characterization of Dissolved Organic Matter by : Fernando Rosario-Ortiz

Download or read book Advances in the Physicochemical Characterization of Dissolved Organic Matter written by Fernando Rosario-Ortiz and published by ACS Symposium. This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of dissolved organic matter (DOM) has fascinated scientists and engineers for at least 60 years - from the initial efforts focused on measuring the concentrations of carbon in marine and aquatic systems, to the discovery of the role of DOM in the formation of disinfection byproducts, all the way to the new emphasis on the detailed understanding of the different functional groups and basic structural features which are the basis for the physicochemical properties of the material. After 50 years of work in the area, there are still many questions regarding DOM. The study of dissolved organic matter (DOM) has fascinated researchers in different fields of science and engineering for many decades. The impact that DOM has on a wide array of environmental processes has resulted in the development of a multidisciplinary community of researchers all focusing on using different analytical techniques and experimental design to better understand DOM. This book offers select case studies focusing on the advanced characterization of DOM in different environments and with respect to different processes. It results from the conclusion of a symposium that E. M. Thurman and I had organized for the 245th meeting of the American Chemical Society, which was held on April 7-11, 2013 in New Orleans, Louisiana.

Pulse of the Stream

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ISBN 13 : 9781369354133
Total Pages : 204 pages
Book Rating : 4.3/5 (541 download)

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Book Synopsis Pulse of the Stream by : Catherine Grace Winters

Download or read book Pulse of the Stream written by Catherine Grace Winters and published by . This book was released on 2016 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Biotic and abiotic factors both play critical roles in the cycling of organic matter and nutrients in aquatic ecosystems. Understanding the relative control of these factors on solute fate and transport in fluvial systems is important for understanding how climatic changes can affect water quality. Many processes that control solute cycling in streams occur at sub-daily scales, making high-frequency, in situ, sub-hourly measurements important for capturing the response of dissolved organic matter and nutrients to changes in the strength of controlling processes. The tightly coupled aquatic and terrestrial environments present in headwater streams make them particularly useful systems for studying high-frequency changes in water chemistry. In this study, we examined the patterns of dissolved organic carbon, nitrate, dissolved oxygen, temperature, dissolved organic matter fluorescence, and stream discharge using in-stream measurements at sub-hourly to monthly time scales to understand the daily and seasonal controls of aquatic organic matter and nutrient processing. We also conducted a laboratory incubation to measure the effects of dissolved organic carbon and nutrient treatments on consumption of carbon and nitrogen in our system. Our main objectives were to identify: 1) the relative controls of diel biotic and abiotic processes on stream dissolved organic carbon and nitrate-N; and 2) the mechanisms controlling rapid autumnal changes in dissolved organic carbon and nitrate-N in stream runoff. We found that hydrology plays a key role in transporting solutes to a forested headwater stream in the Piedmont Region, Maryland; however, once solutes reach the stream biotic controls dominate the stream solute patterns. Biology is an important regulator of diel patterns of streamwater dissolved organic carbon and nitrate concentrations during springtime and autumn leaf fall. Diel cycling is most apparent during the spring prior to leaf out when the water temperature is increasing. Where patterns were evident, nitrate (annual average in second order stream: 17:00) and discharge (17:28) reached their minimums during the afternoon within a few hours of the peaks in dissolved oxygen (13:16), temperature (15:17), dissolved organic carbon (16:06), and dissolved organic matter fluorescence (17:23). Larger amplitudes of dissolved oxygen, nitrate, dissolved organic carbon, and dissolved organic matter fluorescence correspond with larger daily temperature changes. Laboratory incubations showed increased consumption of nitrogen in the presence of labile carbon, but not in the presence of labile carbon plus nutrients, which indicates our system is carbon limited. Autumn dissolved organic carbon and nitrate dynamics also indicate our system is carbon limited. Increased rates of leaf litter fall corresponded with increased consumption of stream nitrate leading to a late October depression, or annual minimum, in nitrate concentration. Storm events accelerated the recovery of stream nitrate to early autumn concentrations as nitrate was mobilized and transported from soils to the stream. Hydrology is important for solute transport to and export from the stream. Autotrophic activity dominates on the daily scale, while heterotrophic activity controls seasonal responses in organic matter and nutrient cycling in this forested watershed. Carbon and nitrogen dynamics have been studied in other forested systems, as well, but the controlling processes vary among these watershed. Our results highlight the importance of understanding controlling processes within specific watersheds when making large scale predictions of the potential export of carbon and nitrogen from forested systems.

Limnology

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Publisher : Academic Press
ISBN 13 : 0080574394
Total Pages : 1023 pages
Book Rating : 4.0/5 (85 download)

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Book Synopsis Limnology by : Robert G. Wetzel

Download or read book Limnology written by Robert G. Wetzel and published by Academic Press. This book was released on 2001-05-10 with total page 1023 pages. Available in PDF, EPUB and Kindle. Book excerpt: Limnology is the study of the structural and functional interrelationships of organisms of inland waters as they are affected by their dynamic physical, chemical, and biotic environments. Limnology: Lake and River Ecosystems, Third Edition, is a new edition of this established classic text. The coverage remains rigorous and uncompromising and has been thoroughly reviewed and updated with evolving recent research results and theoretical understanding. In addition, the author has expanded coverage of lakes to reservoir and river ecosystems in comparative functional analyses.

Biogeochemical Cycling in Lake Superior Tributaries

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Publisher :
ISBN 13 :
Total Pages : 382 pages
Book Rating : 4.:/5 (944 download)

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Book Synopsis Biogeochemical Cycling in Lake Superior Tributaries by : Ashley Anne Coble

Download or read book Biogeochemical Cycling in Lake Superior Tributaries written by Ashley Anne Coble and published by . This book was released on 2015 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt: Seasonal and spatial variability in environmental factors may affect dissolved organic matter composition and nutrient transformation and retention in streams. The objective of this research was to quantify and describe seasonality, quantity, and quality of nutrient processing and export of ammonium (NH4), soluble reactive phosphate (SRP), and dissolved organic carbon (DOC) into Lake Superior through intensive study in a small 1st order watershed coupled with snapshot measurements across 12 tributaries that varied in size, location, and wetland coverage. Our results suggest biodegradable C is exported from a small headwater stream year-round and that DOC mineralization rates can be stimulated by additions of NH4 and labile C (Chapter 2). We found that biodegradable DOC varied synchronously among 3 rivers that varied in size by three orders of magnitude. Furthermore, these rivers exported 9 to 17% of annual DOC in biodegradable form, which may then fuel biological activity in nearshore zones of Lake Superior. Modeling of historical loads of DOC suggests that spring loads of DOC have increased and fall loads have decreased over a 26 year period, but annual loads have not (Chapter 3). Across eleven tributaries variability in NH4 uptake velocity was explained by watershed area, discharge, and fluorescence index of DOC (indicator of microbial and terrestrial sources; Chapter 4). Temporally detailed measurements (every 2 to 4 weeks for 3 years) of nutrient uptake in a small headwater stream indicated light availability, algal and periphyton biomass, solute concentrations, and pH were important predictors of NH4 uptake velocity (Chapter 5). We found a similar magnitude of NH4 uptake velocity during winter and summer measurements while SRP uptake velocity was greater in summer than winter (Chapter 5). Overall the greatest uptake velocities were observed in spring and fall for NH4, in spring for SRP and in fall for DOC (Chapter 5). Collectively, this research demonstrates the temporally dynamic nature of biodegradable carbon and nutrient uptake, the tight coupling of C and N cycling, and the role of DOM composition in stream nutrient uptake in northern temperate forested streams.

Hydrologic Dynamics Control Dissolved Organic Matter Export from Watersheds

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (91 download)

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Book Synopsis Hydrologic Dynamics Control Dissolved Organic Matter Export from Watersheds by : Rebecca Anne Bellmore

Download or read book Hydrologic Dynamics Control Dissolved Organic Matter Export from Watersheds written by Rebecca Anne Bellmore and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dissolved organic matter (DOM) is an important component of nutrient cycling and energy transfer within and between ecosystems. Understanding controls over the magnitude and quality of DOM that is transferred from soils to surface water is needed to better characterize the terrestrial-aquatic carbon flux and effects of terrestrial DOM on downstream ecosystems. A meta-analysis of the response of in-stream dissolved organic nitrogen concentration (DON) to high flow events indicates that DON typically increases with flow across a wide range of ecosystem types, likely as novel DOM sources in the landscape are mobilized and transported to streams and rivers. Mechanisms controlling DOM export, including dissolved organic carbon (DOC) and DON concentrations and the quality of DOM, were examined in a small agricultural catchment in eastern Washington State. In the soil column, DOC concentration declined and source of DOM shifted from humic-like and plant-derived to microbially-derived with depth through the profile. Across seasons and years, DOM exported via drain discharge during low flows resembled that found deep in the soil profile, and DOM exported during high flows suggests topsoil and litter sources contribute to export. A simple mixing model suggests that litter leachate can contribute over 50% of DOM during peak flow. Based on modeled contributions of litter, topsoil and subsoil DOM during storm events, DOC concentration is over-predicted, except for peak flows, suggesting removal via sorption and/or microbial decomposition in the soil column control DOC export on the timescale of events. Although the character of exported DOM shifts with flow conditions, laboratory incubations suggest bioavailability to the stream sediment microbial community is consistently low, with a maximum of 7% loss over 6 days, indicating exported DOM is likely transported beyond the immediate stream reach. An analysis of anticipated effects of climate change on the flow regime in the catchment projects the wettest years to become more variable, with non-linear effects on the magnitude of DOC export. Finally I explore how climate change assessments can be incorporated into nonpoint source nutrient management plans, despite current uncertainty about the magnitude and timeframe of climate effects on nutrient loading.

Aquatic Ecosystems: Interactivity of Dissolved Organic Matter

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Publisher : Academic Press
ISBN 13 : 0122563719
Total Pages : 534 pages
Book Rating : 4.1/5 (225 download)

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Book Synopsis Aquatic Ecosystems: Interactivity of Dissolved Organic Matter by : Stuart Findlay

Download or read book Aquatic Ecosystems: Interactivity of Dissolved Organic Matter written by Stuart Findlay and published by Academic Press. This book was released on 2003 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: Overviews of the source, supply and variability of DOM, surveys of the processes that mediate inputs to microbial food webs, and syntheses consolidating research findings provide a comprehensive review of what is known of DOM in freshwater. This book will be important to anyone interested in understanding the fundamental factors associated with DOM that control aquatic ecosystems."--BOOK JACKET.

Dissolved Organic Matter in Atmospheric Deposition

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ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (971 download)

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Book Synopsis Dissolved Organic Matter in Atmospheric Deposition by : Lidiia Iavorivska

Download or read book Dissolved Organic Matter in Atmospheric Deposition written by Lidiia Iavorivska and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Dissolved organic matter (DOM) in the atmosphere affects air quality and climate. Unlike inorganic constituents that typically consist of single compounds, DOM is a mixture of multiple organic compounds having varying molecular weights, reactivity and solubility. Dissolved organic carbon (DOC) is typically used as a measure of the total DOM present in solution. In the atmosphere, DOC originates from emissions of various biogenic and anthropogenic sources, such as vegetation, incomplete combustion of fossil fuels, biomass burning, and sea-spray. The ultimate fate of atmospheric DOC is to be oxidized to inorganic forms of carbon dioxide and carbon monoxide, or to be removed from the atmosphere and transferred to the landscape through deposition. Deposition can occur as wet deposition via precipitation and as dry deposition via surface settling of particles and gases. The concentration, or quantity, of DOC in precipitation plays an important role in the carbon cycle and in other elemental cycles; while the chemical composition, or quality, of DOC in precipitation largely determines its fate in the environment. Rain and snow deposited to the landscape are a source of nutrient enrichment to ecosystems and water bodies, and are especially important as an input of carbon in coastal regions. Since DOC in precipitation is highly chemically reactive and bioavailable it influences rates of productivity in aquatic ecosystems. Despite the significance of DOC to many ecosystem processes, knowledge about its contributions to landscapes in precipitation remains limited. With anthropogenic influences on the carbon cycle now widely recognized, the need for synthesis of existing datasets on atmospheric deposition of DOC and further determining its rates and drivers is great. My dissertation is focused on wet deposition of DOC and assesses the magnitude and patterns of variation of organic matter in precipitation over space and time. The dissertation is organized into four manuscripts. Chapter 1 is a literature review where I provide a new data synthesis from 83 contemporary, peer-reviewed studies where organic carbon (OC) in precipitation was measured at sites around the world. Data regarding the concentrations of OC in precipitation and rates of atmospheric deposition were compiled in a common set of units and presented along with the summary statistics. These data give insights into the magnitude and regional variability of OC in precipitation. Organic carbon was ubiquitous in precipitation in rural and urban locations; with DOC in precipitation spanning several orders of magnitude between locations. This synthesis brings attention to atmospheric deposition as an under-sampled piece of the global carbon cycle; highlights gaps in data availability and challenges for data inter-comparison; and provides a unique data set that can be used for toward exploring future changes in the carbon cycle. Chapter 2 aims to understand how DOC concentration and composition in precipitation change temporally from storm to storm. Precipitation samples were collected at the Susquehanna Shale Hills Critical Zone Observatory watershed (Pennsylvania, USA) during 90 storm events. Observational data revealed temporal variability associated with seasonality and meteorological conditions. Using a mixed modeling statistical approach, I showed that there are multiple processes that work in synergy to influence the quantity and quality of DOC in precipitation. Factors related to storm properties, emission sources, and to the chemical composition of the atmosphere could explain more than 60% of the storm to storm variability in DOC concentrations. This study provided observations on changes in DOC that can be useful in modeling of atmospheric chemistry and in considering temporal changes in ecosystem nutrient balances and microbial activity.Chapter 3 explores how DOC concentration and composition vary throughout the course of storm events. I measured DOC in sequential samples during 13 storms at the Shale Hills watershed. The observational data generated hypotheses about potential factors that influence variability of DOC within storms. While previous studies have observed that concentrations of other elements in precipitation typically decrease over the course of individual storms, results from this study showed that DOC concentrations are highly variable. During most storms concentrations decreased towards the end of the event; however increasing concentrations in the later stages of some storms highlight that DOC removal with precipitation is not merely an exponential decay process. The variability of DOC during events is related to the balance between the cloud microphysics, atmospheric chemical transformations, and synoptic scale gradients in the abundance of organic compounds in the boundary layer. This work advances understanding of physicochemical processes occurring during storms that are relevant to studies of atmospheric chemistry, carbon cycling, and ecosystem responses.Chapter 4 quantifies spatial gradients in wet atmospheric DOC deposition across the state of Pennsylvania (USA). DOC concentrations were measured in selected precipitation samples collected for six years at a network of atmospheric deposition monitoring sites. A simple modeling approach was used to estimate the first statewide, annual estimates of wet atmospheric DOC deposition. Results showed that DOC inputs with wet deposition in Pennsylvania represented about one-third as much as literature reported values for DOC exported by rivers from watersheds in the region. The rates of DOC wet deposition showed a pronounced seasonality and spatial distribution, with highest deposition rates observed in the summer, especially at the sites located in western Pennsylvania.

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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Publisher :
ISBN 13 :
Total Pages : 200 pages
Book Rating : 4.:/5 (931 download)

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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:

Stream Ecology

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Publisher : Springer Nature
ISBN 13 : 3030612864
Total Pages : 485 pages
Book Rating : 4.0/5 (36 download)

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Book Synopsis Stream Ecology by : J. David Allan

Download or read book Stream Ecology written by J. David Allan and published by Springer Nature. This book was released on 2021-03-17 with total page 485 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stream Ecology: Structure and Function of Running Waters is designed to serve as a textbook for advanced undergraduate and graduate students, and as a reference source for specialists in stream ecology and related fields. This Third Edition is thoroughly updated and expanded to incorporate significant advances in our understanding of environmental factors, biological interactions, and ecosystem processes, and how these vary with hydrological, geomorphological, and landscape setting. The broad diversity of running waters – from torrential mountain brooks, to large, lowland rivers, to great river systems whose basins occupy sub-continents – makes river ecosystems appear overwhelming complex. A central theme of this book is that although the settings are often unique, the processes at work in running waters are general and increasingly well understood. Even as our scientific understanding of stream ecosystems rapidly advances, the pressures arising from diverse human activities continue to threaten the health of rivers worldwide. This book presents vital new findings concerning human impacts, and the advances in pollution control, flow management, restoration, and conservation planning that point to practical solutions. Reviews of the first edition: ".. an unusually lucid and judicious reassessment of the state of stream ecology" Science Magazine "..provides an excellent introduction to the area for advanced undergraduates and graduate students..." Limnology & Oceanography "... a valuable reference for all those interested in the ecology of running waters." Transactions of the American Fisheries Society Reviews of the second edition: "Overall, a must for the field centre and a good starter text in stream ecology." (TEN News, October, 2007) "Highly recommended. Upper-division undergraduates through faculty." (P. R. Pinet, CHOICE, Vol. 45 (7), 2008) "... a very good, fluidly readable book which contains the latest key scientific knowledge of the ecology of running waters." (Daniel Graeber, International Review of Hydrobiology, Vol. 94 (2), 2009)

Estuarine Processes: Uses, stresses, and adaptation to the estuary

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Publisher :
ISBN 13 :
Total Pages : 568 pages
Book Rating : 4.:/5 (318 download)

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Book Synopsis Estuarine Processes: Uses, stresses, and adaptation to the estuary by : Martin L. Wiley

Download or read book Estuarine Processes: Uses, stresses, and adaptation to the estuary written by Martin L. Wiley and published by . This book was released on 1976 with total page 568 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Resolving Spatial and Temporal Variability in Dissolved Organic Matter Characteristics Within Combined Agricultural and Stormwater Conveyances

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Publisher :
ISBN 13 :
Total Pages : pages
Book Rating : 4.:/5 (1 download)

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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.

Biogeochemistry of Marine Dissolved Organic Matter

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Publisher : Academic Press
ISBN 13 : 0124071538
Total Pages : 712 pages
Book Rating : 4.1/5 (24 download)

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Book Synopsis Biogeochemistry of Marine Dissolved Organic Matter by : Dennis A. Hansell

Download or read book Biogeochemistry of Marine Dissolved Organic Matter written by Dennis A. Hansell and published by Academic Press. This book was released on 2014-10-02 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt: Marine dissolved organic matter (DOM) is a complex mixture of molecules found throughout the world's oceans. It plays a key role in the export, distribution, and sequestration of carbon in the oceanic water column, posited to be a source of atmospheric climate regulation. Biogeochemistry of Marine Dissolved Organic Matter, Second Edition, focuses on the chemical constituents of DOM and its biogeochemical, biological, and ecological significance in the global ocean, and provides a single, unique source for the references, information, and informed judgments of the community of marine biogeochemists. Presented by some of the world's leading scientists, this revised edition reports on the major advances in this area and includes new chapters covering the role of DOM in ancient ocean carbon cycles, the long term stability of marine DOM, the biophysical dynamics of DOM, fluvial DOM qualities and fate, and the Mediterranean Sea. Biogeochemistry of Marine Dissolved Organic Matter, Second Edition, is an extremely useful resource that helps people interested in the largest pool of active carbon on the planet (DOC) get a firm grounding on the general paradigms and many of the relevant references on this topic. Features up-to-date knowledge of DOM, including five new chapters The only published work to synthesize recent research on dissolved organic carbon in the Mediterranean Sea Includes chapters that address inputs from freshwater terrestrial DOM