Browsing Earth and Environmental Sciences by Title
Now showing items 329-348 of 434
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Quantification of Oxygen Dynamics in the Grand River Using a Stable Isotope Approach
(University of Waterloo, 2010-04-30)The current study monitored DO, stable isotopes of O2 (δ18O-O2 and δ18O-H2O) along with water quality parameters on both a diel and day-time only basis in the Grand River over several seasons and locations. A dynamic dual ... -
Quantification of the Long-Term Effects from Nutrient Reductions on Groundwater Nitrate Concentrations in an Agricultural Setting
(University of Waterloo, 2008-06-06)The Ontario Nutrient Management Act (2002) recommends agricultural Beneficial Management Practices (BMPs) that involve reductions in nutrient applications of nitrogen (N) to fields to improve underlying groundwater quality, ... -
Quantifying Groundwater Recharge Under Dynamic Seasonality in Cold Climates
(University of Waterloo, 2018-01-18)Estimating groundwater recharge in cold climates during periods of dynamic seasonality such as winter melt periods and spring freshets is challenging due to subsurface heterogeneities and the complexity of vadose zone ... -
Quantifying the Effects of Water Management Decisions on Streambank Stability
(University of Waterloo, 2022-09-30)Streams continuously change due to natural processes and human activities, significantly affecting streambank erosion and stability. These changes cause severe environmental issues, including sedimentation of reservoirs, ... -
Quantifying the Groundwater Component within the Water Balance of a Large Lake in a Glaciated Watershed: Lake Pyhäjärvi, SW Finland
(University of Waterloo, 2012-01-20)Accurate estimates of the amount of groundwater entering a lake on a yearly basis may provide valuable information for assessing contaminant loadings such as nutrient mass fluxes and the subsequent contribution of groundwater ... -
Quantifying the role of reservoirs in altering phosphorus dynamics using a combination of data analysis and process modeling
(University of Waterloo, 2022-04-29)Excess phosphorus (P) from agricultural watersheds promotes eutrophication in downstream aquatic systems. Reservoirs retain P generated from farm fields and protect downstream waters. Reservoirs also act as hotspots for P ... -
Quantitative modeling of nitrogen cycling along the river continuum: streambed sediments, reservoirs, and isotopes
(University of Waterloo, 2018-09-26)The vast release of anthropogenically produced reactive nitrogen (N) into the environment, by agricultural activities, energy production and municipal wastewater, has led to a variety of consequences for atmospheric, ... -
Quaternary Stratigraphy and Glacial Dynamics from a Core Region of the Laurentide Ice Sheet, Aberdeen Lake, Kivalliq, Nunavut
(University of Waterloo, 2015-01-16)Central Kivalliq, mainland Nunavut west of Hudson Bay and north of Manitoba, was a long-standing core region of the Laurentide Ice Sheet (LIS). The location of the Keewatin Ice Divide (KID), a major ice spreading region ... -
Ra-228, Ra-226, Ra-224 and Ra-223 in potential sources and sinks of land-derived material in the German Bight of the North Sea: implications for the use of radium as a tracer
(Springer, 2011-08-01)Activities of the naturally occurring radium nuclides Ra-228, Ra-226, Ra-224 and Ra-223 were determined in waters of the open German Bight and adjacent nearshore areas in the North Sea, in order to explore the potential ... -
Radial Movement of a Passively Released Gas from a Monitoring Well
(University of Waterloo, 2009-09-01)In order to preserve groundwater as a viable source of drinking water, remedial measures must be applied where appropriate. The application of the various remedial technologies is site and contaminant dependent. Differing ... -
Rare earth elements and radiogenic strontium isotopes in carbonate minerals reveal diagenetic influence in shales and limestones in the Appalachian Basin
(Elsevier, 2019-03-30)Rare earth element (REE) signatures are often applied to interpret paleoenvironmental conditions in sedimentary basins, however the complicated diagenetic histories in dynamic depositional environments can affect interpretation ... -
Reconstruction of Local and Global Marine Paleoredox Conditions during Deposition of the Devonian-Mississippian Exshaw Formation (Black Shale Member) and the Evaluation of Hydrocarbon Maturation Effects
(University of Waterloo, 2019-07-17)The end-Devonian Hangenberg event represented one of the biggest Phanerozoic mass extinctions. However, the potential mechanism(s) for triggering this event, including climate cooling, sea-level change, glaciation and ocean ... -
Reconstruction of local and global marine paleoredox conditions for the northeast-Panthalassan (British Columbia, Canada) expression of the Toarcian Oceanic Anoxic Event using a multi-proxy approach
(University of Waterloo, 2020-01-23)The Toarcian Oceanic Anoxic Event (T-OAE) of the Early Jurassic is one of several Mesozoic instances of expanded ocean anoxia, coupled with feedbacks and perturbations in Earth’s systems. The drivers for these feedbacks ... -
Reconstruction of Local and Global Marine Redox Conditions During Deposition of Late Ordovician and Early Silurian Organic-Rich Mudrocks in the Siljan Ring District, Central Sweden
(University of Waterloo, 2016-01-12)The Ordovician-Silurian transition witnessed the second largest mass extinction in the Phanerozoic Eon and the Hirnantian glaciation. We measured U (as δ238U relative to standard CRM145 = 0‰) and Mo (as δ98Mo relative to ... -
Reconstruction of Paleoclimate Time-Series in the Peace-Athabasca Delta, Northern Alberta, from Stable Isotopes in Tree-Rings
(University of Waterloo, 2008-08-12)The isotopic labelling of carbon in tree-rings varies as a function of growth season temperature and relative humidity. The isotopic labelling of oxygen in tree-rings varies as a function of source-water isotopic composition ... -
Redox conditions across the Cambrian–Ordovician boundary: Elemental and isotopic signatures retained in the GSSP carbonates
(Elsevier, 2015-12-15)Lime mudstone samples (rhythmites) were collected at high resolution from outcrops of the Cambrian–Ordovician GSSP boundary section at Green Point (western Newfoundland, Canada). The sequence (~45 mthick) consists of slope ... -
Reduction of TCE and Chromate by Granular Iron in the Presence of Dissolved CaCO<sub>3</sub>
(University of Waterloo, 2006)Iron permeable reactive barriers (PRBs) have been installed at sites contaminated with various reducible organic and inorganic chemicals, particularly chlorinated solvents, worldwide. Many geochemical factors can affect ... -
The relationship between retail type and transportation emissions
(University of Waterloo, 2013-09-03)This study investigates the relationship between three types of retail, Big Box, traditional and online retail, and their transportation related emissions. The study takes a comprehensive approach by examining both the ... -
Remediation of Pentaerythritol Tetranitrate (PETN) Contaminated Water and Soil
(University of Waterloo, 2007-11-28)Pentaerythritol tetranitrate (PETN), a nitrate ester, is widely used as a powerful explosive and is classified as a munitions constituent of great concern by DoD in U.S.A. It is an environmental concern and poses a threat ... -
Remote Paleohydrograph Reconstruction of the Stockton Island Tombolo
(University of Waterloo, 2021-05-01)Rising lake levels have become a concern for the coasts of Lake Superior and one such coastline is the Stockton Island Tombolo (SIT) that protects the Pine Barrens Habitat (PBH) in the Apostle Islands National Lakeshore ...