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Full-Text Articles in Hydrology
Hydrologic Controls On Phosphorus Speciation And Mobilization In A Subalpine Watershed (East River, Colorado), Lucia Isobel Arthen-Long
Hydrologic Controls On Phosphorus Speciation And Mobilization In A Subalpine Watershed (East River, Colorado), Lucia Isobel Arthen-Long
Masters Theses
The cycling of phosphorus (P) through floodplain environments is critical to ecosystem productivity and has significant implications on both water quality and soil fertility. P export from soils in response to saturation has been well documented, but the relative vulnerability of specific P pools to mobilization remains poorly constrained, as do the mechanisms mediating its release. The prediction of P availability in and export from mountainous floodplain soils is of great importance as global climate change is projected to significantly alter precipitation regimes in alpine systems. This study combined a thorough characterization of P distribution across a hillslope to floodplain …
Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro
Nitrogen Dynamics And Transport Along Flowpaths In A Rural Wetland-Stream Complex, Colton Kyro
Graduate Student Theses, Dissertations, & Professional Papers
Human activities have doubled the rate of nitrogen inputs onto the landscape resulting in elevated nitrogen concentrations in our streams. Anthropogenically applied nitrogen is largely transported to stream networks via groundwater movement. Groundwater discharge occurs in distinct points along a stream but whose influences can often persist far beyond that area due to insufficient biogeochemical removal of imported nitrogen potentially causing alterations in community structure and precipitating large algae blooms. To understand the factors governing nitrogen abundance in a historical polluted stream, I used a mass-balance approach to quantify groundwater-surface water interaction and the magnitude of groundwater nitrogen input and …
Spatiotemporal Dynamics Of Nitrogen And Carbon Biogeochemistry In A Wetland-Stream Sequence, Patrick E. Hurley
Spatiotemporal Dynamics Of Nitrogen And Carbon Biogeochemistry In A Wetland-Stream Sequence, Patrick E. Hurley
Graduate Student Theses, Dissertations, & Professional Papers
Studies of aquatic ecosystems often segregate streams from the influential ponds, lakes, and wetland zones that act as important transitions between terrestrial and fluvial systems. Across the aquatic landscape, these zones interact to form linked ecosystems that function as discrete nutrient processing domains, shifting biogeochemical signals due to spatial and temporal variability in hydrologic and biologic controls. Using a mass-balance approach, we profiled nutrient dynamics along a 23-km wetland-stream sequence over three seasons. Hydrologic, morphologic, and biologic conditions, as well as landscape attributes, were quantified to determine potential controls on biogeochemical cycling in a tributary of the Upper Clark Fork …
The Effects Of Seasonal Variations In Chemistry And Hydrology On The Microbial Community And Its Sulfide Oxidation Potential In A Naturally Acidic Maine Stream, Raymond C. Kahler Iii
The Effects Of Seasonal Variations In Chemistry And Hydrology On The Microbial Community And Its Sulfide Oxidation Potential In A Naturally Acidic Maine Stream, Raymond C. Kahler Iii
Electronic Theses and Dissertations
Sulfide minerals oxidize through interaction with water and oxygen, releasing hydrogen ions. The process often occurs naturally near metal sulfide deposits, and can be accelerated through mining. Microorganisms accelerate the rate of sulfide oxidation. Acidified streams typically contain high metal concentrations (e.g. aluminum) and microbes in these systems may develop resistances to metal toxicity. Stream flow can affect sulfide oxidation and microbial community structure. Baseflow can influence stream chemistry from interactions with the surrounding bedrock, while stormflow affects stream chemistry and the local microbial community through dilution and addition of microbes transported by runoff. Microbial community composition is affected by …
Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd
Graduate Theses and Dissertations
The natural flow regime exerts primacy over lotic ecosystem patterns and processes. However, little work has examined the influence of flow regime on instream and riparian carbon (C) dynamics in minimally-impacted, temperate forested systems. To date, most research efforts have focused on characterizing C movement and transformations across biomes and land use categories; however, flow regime represents an overlooked, finer level of detail that may drive differences in ecosystem function. My dissertation objective was to measure C fixation and movement within and across multiple environmental spheres (e.g. within stream channels, between stream surfaces and the atmosphere, and from riparian soils …
Synthesis Of Satellite Microwave Observations For Monitoring Global Land-Atmosphere Co2 Exchange, Lucas Alan Jones
Synthesis Of Satellite Microwave Observations For Monitoring Global Land-Atmosphere Co2 Exchange, Lucas Alan Jones
Graduate Student Theses, Dissertations, & Professional Papers
This dissertation describes the estimation, error quantification, and incorporation of land surface information from microwave satellite remote sensing for modeling global ecosystem land-atmosphere net CO2 exchange. Retrieval algorithms were developed for estimating soil moisture, surface water, surface temperature, and vegetation phenology from microwave imagery timeseries. Soil moisture retrievals were merged with model-based soil moisture estimates and incorporated into a light-use efficiency model for vegetation productivity coupled to a soil decomposition model. Results, including state and uncertainty estimates, were evaluated with a global eddy covariance flux tower network and other independent global model- and remote-sensing based products.
Wetlands And Greenhouse Gas Fluxes: Causes And Effects Of Climate Change – A Meta-Analysis, Robert E. Ventura
Wetlands And Greenhouse Gas Fluxes: Causes And Effects Of Climate Change – A Meta-Analysis, Robert E. Ventura
Pomona Senior Theses
Climate change is one of the largest problems facing this generation. Anthropogenically caused increases of greenhouse gas emissions is a significant culprit to this problem. Although the obvious problems such as cars, industry, and urbanism garnish a significant amount of the criticism, natural sources such as wetlands are also beginning to contribute to this issue. This is becoming increasingly significant as wetlands shift from being sinks of greenhouse gases to becoming sources as various anthropogenic impacts, including global warming itself, begin to affect the health of the wetlands. The aim of this project is to look at four common types …