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Book Linking Temporal and Spatial Variability of Millennial and Decadal Scale Sediment Yield to Aquatic Habitat in the Columbia River Basin

Download or read book Linking Temporal and Spatial Variability of Millennial and Decadal Scale Sediment Yield to Aquatic Habitat in the Columbia River Basin written by Elijah Portugal and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Eco-geomorphic interactions occur across a range of spatial and temporal scales from the level of the entire watershed to an individual geomorphic unit within a stream channel. Predicting the mechanisms, rates and timing of sediment production and storage in the landscape are fundamental problems in the watershed sciences. This is of particular concern given that excess sedimentation is considered a major pollutant to aquatic ecosystems. Rates of sediment delivery to stream networks are characteristically unsteady and non-uniform. Because of this, conventional approaches for predicting sediment yield provide incomplete and often inaccurate information. Terrestrial cosmogenic nuclides (TCNs) provide an estimate of spatially averaged rates of sediment yield from 101 to 104 km2 and temporally integrated from 103 to 105 years. Here, I used TCNs to constrain unsteadiness and non-uniformity of sediment yield within specific catchments of the Columbia River Basin (CRB). This is in combination with GIS analysis optically stimulated luminescence (OSL), Carbon-14 (C14) dating of fluvial deposits, and rapid geomorphic assessments. Results showed an order of magnitude spatial variability in the rates of millennial-scale sediment yield at the scale of the entire CRB. At the broadest scale long-term rates of sediment yield generally are poorly predicted from topographic and environmental parameters. A notable exception is the observed positive correlation between mean annual precipitation and sediment yield. Where functional relationships exist, the nature of those relationships are scale and situation-dependent. In addition to the broadest scale, each smaller watershed (e.g., ~ 10 0́3 2,000 km2) has a distinct geologic, geomorphic, and disturbance history that sets the template for the modern sediment dynamics and the physical aspects of aquatic habitat. Chapter 2 presents results of broad-scale trends while Chapter 3 is comprised of case studies from smaller watersheds. Finally, Chapter 4 explores the relationship between long-term sediment yield and modern channel form.

Book Spatial and Temporal Variation of Stream Water Chemistry at the Plynlimon Catchments

Download or read book Spatial and Temporal Variation of Stream Water Chemistry at the Plynlimon Catchments written by T. Locks and published by . This book was released on 1996 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Spatial and Temporal Variability of Sediment Sources in the Upper Rh ne Basin Switzerland

Download or read book Spatial and Temporal Variability of Sediment Sources in the Upper Rh ne Basin Switzerland written by Laura Stutenbecker and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Spatial and Temporal Variability in Sediment Movement and the Role of Woody Debris in a Sub alpine Stream Colorado

Download or read book Spatial and Temporal Variability in Sediment Movement and the Role of Woody Debris in a Sub alpine Stream Colorado written by Carolyn R. Trayler and published by . This book was released on 1997 with total page 310 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Evaluating Spatial and Temporal Variations of Water Chemistry and the Impact of Transient Storage on Solute Transport in Low order Mountain Streams

Download or read book Evaluating Spatial and Temporal Variations of Water Chemistry and the Impact of Transient Storage on Solute Transport in Low order Mountain Streams written by Li Jin and published by . This book was released on 2008 with total page 284 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Assessment and modelling of spatial temporal variability in upland stream chemistry

Download or read book Assessment and modelling of spatial temporal variability in upland stream chemistry written by H J. Foster and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Spatial and Temporal Dynamics of Biogeochemical Processes in the Fraser River Canada

Download or read book Spatial and Temporal Dynamics of Biogeochemical Processes in the Fraser River Canada written by Britta Marie Voss and published by . This book was released on 2014 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: The great geologic and climatic diversity of the Fraser River basin in southwestern Canada render it an excellent location for understanding biogeochemical cycling of sediments and terrigenous organic carbon in a relatively pristine, large, temperate watershed. Sediments delivered by all tributaries have the potential to reach the ocean due to a lack of main stem lakes or impoundments, a unique feature for a river of its size. This study documents the concentrations of a suite of dissolved and particulate organic and inorganic constituents, which elucidate spatial and temporal variations in chemical weathering (including carbonate weathering in certain areas) as well as organic carbon mobilization, export, and biogeochemical transformation. Radiogenic strontium isotopes are employed as a tracer of sediment provenance based on the wide variation in bedrock age and lithology in the Fraser basin. The influence of sediments derived from the headwaters is detectable at the river mouth, however more downstream sediment sources predominate, particularly during high discharge conditions. Bulk radiocarbon analyses are used to quantify terrestrial storage timescales of organic carbon and distinguish between petrogenic and biospheric organic carbon, which is critical to assessing the role of rivers in long-term atmospheric CO2 consumption. The estimated terrestrial residence time of biospheric organic carbon in the Fraser basin is 650 years, which is relatively short compared to other larger rivers (Amazon, Ganges-Brahmaputra) in which this assessment has been performed, and is likely related to the limited floodplain storage capacity and non-steady-state post-glacial erosion state of the Fraser River. A large portion of the dissolved inorganic carbon load of the Fraser River (>80%) is estimated to derive from remineralization of dissolved organic carbon, particularly during the annual spring freshet when organic carbon concentrations increase rapidly. This thesis establishes a baseline for carbon cycling in a largely unperturbed modern mid-latitude river system and establishes a framework for future process studies on the mechanisms of organic carbon turnover and organic matter-mineral associations in river systems.

Book Temporal and Spatial Variability and Controls of Sediment Yield in Selected Drainage Basins of Southwestern Pennsylvania USA

Download or read book Temporal and Spatial Variability and Controls of Sediment Yield in Selected Drainage Basins of Southwestern Pennsylvania USA written by Belayet H. Khan and published by . This book was released on 1985 with total page 404 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book A High Resolution Study of the Spatial and Temporal Variability of Natural and Anthropogenic Compounds in Offshore Lake Superior Sediments

Download or read book A High Resolution Study of the Spatial and Temporal Variability of Natural and Anthropogenic Compounds in Offshore Lake Superior Sediments written by Jon D. Van Alstine and published by . This book was released on 2006 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Book Sediment Dynamics and Implications for Sediment associated Contaminants in the Peace Athabasca and Slave River Basins

Download or read book Sediment Dynamics and Implications for Sediment associated Contaminants in the Peace Athabasca and Slave River Basins written by Michael A. Carson and published by . This book was released on 1997 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Examines the mechanisms of natural riverine sediment production in the Northern River Basins Study area, together with the routine data for suspended sediment in the area's rivers, as background for the examination of sediment-associated contaminants. Topics examined include: the causative mechanisms and boundary conditions affecting the sediment regime, including area topography, geology, and hydrology; availability and adequacy of data on suspended sediments in the area; time trends of fluvial suspended sediment dynamics on a seasonal (open water and ice regime) and annual basis, over the long term, and in critical events; sediment sources, pathways, and fates, and sediment dynamics at basin-wide, reach, and site levels; sediment quality, including sediment-associated characteristics of pulp mill effluents and sediment-contaminant relationships; and implications for sediment-associated contaminants. Recommendations are made for monitoring and assessment of the sediment component of the area's ecosystem.

Book Temporal Influences of Seasonal Hypoxia on Sediment Biogeochemistry in Coastal Sediments

Download or read book Temporal Influences of Seasonal Hypoxia on Sediment Biogeochemistry in Coastal Sediments written by Karen S. Sell and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Bottom water hypoxia and its influence on the environment have been topics of increasing concern for many coastal regions. This research addresses both spatial and temporal variability in sediment biogeochemistry at the southeastern region of Corpus Christi Bay, TX, where seasonal (summer) hypoxia occurs. Traditional techniques for determination of a variety of dissolved and solid components, benthic oxygen demand, and sulfate reduction rates were augmented by measurements using solid state microelectrodes to simultaneously determine concentrations of dissolved O2, Mn2+, Fe2+, and [sigma]H2S in multiple small - interval (1 mm) depth profiles of sediment microcosms. Oxygen concentrations in the overlying water were manipulated in the sediment microcosms and electrode depth profile measurements were made over %7E 500 hours of experimentation. Laboratory and field microelectrode results were in good agreement for both norm - oxic and anoxic time periods. Results indicated that iron (Fe2+) and sulfide ([sigma]H2S) were the redox reactive species in these sediments. During hypoxic conditions an upward migration of dissolved Fe2+ and [sigma]H2S through the sediment column and, at times, into the overlying water was observed as the dissolved oxygen concentrations decreased. A corresponding decline in the vertical extent of these redox species occurred when the overlying water was re-oxidized. When both dissolved iron and sulfide coexisted, FeS minerals were formed in the sediment, preventing sulfide diffusion into the overlying water. However, after a long duration of hypoxia (> 200 hours) this buffering capacity was exceeded and both iron and sulfide penetrated into the overlying waters. Results indicated that iron may have a greater influence on hypoxia than sulfide because its concentration in the overlying waters during induced hypoxia was an order of magnitude greater than those of sulfide. Moreover, in the southeastern region of the Bay, where mixing was minimal and the water column was shallow, the sediments alone may have caused the onset of the hypoxic event in a relatively short time period (