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Estimating The Permanent Loss Of Groundwater Storage In The Southern San Joaquin Valley, California, Ryan G. Smith, Rosemary Knight, J. Chen, J. A. Reeves, H. A. Zebker, T. Farr, Z. Liu 2018 Missouri University of Science and Technology

Estimating The Permanent Loss Of Groundwater Storage In The Southern San Joaquin Valley, California, Ryan G. Smith, Rosemary Knight, J. Chen, J. A. Reeves, H. A. Zebker, T. Farr, Z. Liu

Ryan G. Smith

In the San Joaquin Valley, California, recent droughts starting in 2007 have increased the pumping of groundwater, leading to widespread subsidence. In the southern portion of the San Joaquin Valley, vertical subsidence as high as 85 cm has been observed between June 2007 and December 2010 using Interferometric Synthetic Aperture Radar (InSAR). This study seeks to map regions where inelastic (not recoverable) deformation occurred during the study period, resulting in permanent compaction and loss of groundwater storage. We estimated the amount of permanent compaction by incorporating multiple data sets: the total deformation derived from InSAR, estimated skeletal-specific storage and hydraulic ...


Overpumping Leads To California Groundwater Arsenic Threat, Ryan G. Smith, Rosemary Knight, Scott Fendorf 2018 Missouri University of Science and Technology

Overpumping Leads To California Groundwater Arsenic Threat, Ryan G. Smith, Rosemary Knight, Scott Fendorf

Ryan G. Smith

Water resources are being challenged to meet domestic, agricultural, and industrial needs. To complement finite surface water supplies that are being stressed by changes in precipitation and increased demand, groundwater is increasingly being used. Sustaining groundwater use requires considering both water quantity and quality. A unique challenge for groundwater use, as compared with surface water, is the presence of naturally occurring contaminants within aquifer sediments, which can enter the water supply. Here we find that recent groundwater pumping, observed through land subsidence, results in an increase in aquifer arsenic concentrations in the San Joaquin Valley of California. By comparison, historic ...


Characterization Of Kelyphite Rims: Relevance To Diamond Exploration, Mallory N.G. Metcalf 2018 The University of Western Ontario

Characterization Of Kelyphite Rims: Relevance To Diamond Exploration, Mallory N.G. Metcalf

Electronic Thesis and Dissertation Repository

A detailed investigation into the mineralogy and chemistry of kelyphitic rims/veins on garnets was conducted using µXRD, EPMA and Raman spectroscopy for a suite of samples from economic and non-economic kimberlites in Canada and South Africa. Mineralogy demonstrates the influence of metasomatic fluids during the reactions which produced kelyphite in all localities and was used to propose P-T regions where kelyphite could have formed. Using chemical analyses of host garnets and the mineralogy obtained for kelyphite, modified chemical reactions representing Types 1 and 2 kelyphite are provided to describe kelyphite reactions in open systems. Elastically-strained secondary garnet is common ...


Reducing High Flows And Sediment Loading Through Increased Water Storage In An Agricultural Watershed Of The Upper Midwest, Usa, Nate Mitchell, Karthik Kumarasamy, Se Jong Cho, Patrick Belmont, Brent Dalzell, Karen Gran 2018 Indiana University Bloomington

Reducing High Flows And Sediment Loading Through Increased Water Storage In An Agricultural Watershed Of The Upper Midwest, Usa, Nate Mitchell, Karthik Kumarasamy, Se Jong Cho, Patrick Belmont, Brent Dalzell, Karen Gran

Watershed Sciences Faculty Publications

Climate change, land clearing, and artificial drainage have increased the Minnesota River Basin’s (MRB) stream flows, enhancing erosion of channel banks and bluffs. Accelerated erosion has increased sediment loads and sedimentation rates downstream. High flows could be reduced through increased water storage (e.g., wetlands or detention basins), but quantifying the effectiveness of such a strategy remains a challenge. We used the Soil and Water Assessment Tool (SWAT) to simulate changes in river discharge from various water retention site (WRS) implementation scenarios in the Le Sueur watershed, a tributary basin to the MRB. We also show how high flow ...


Effects Of Volcanicity In Iceland, LILIAN Njoki NG'ANG'A 2018 Embry-Riddle Aeronautical University

Effects Of Volcanicity In Iceland, Lilian Njoki Ng'ang'a

Student Works

Iceland is greatly known for its volcanicity as there are several eruptions that have occurred over the years. The country’s volcanology is due to its location on the Mid-Atlantic Ridge, which is a divergent tectonic boundary (Promote Iceland, n.d.). Due to this, the country is known to be responsible for a third of all the fresh lava on earth (Marteinn, 2018).

This research provides a deep dive into the effects of volcanicity and how the Icelandic people have adapted to it. The methods used to collect data for this research were secondary sources and interviews. It was evident ...


Impact Craters On Titan: Finalizing Titan's Crater Population, Joshua E. Hedgepeth 2018 The University of Western Ontario

Impact Craters On Titan: Finalizing Titan's Crater Population, Joshua E. Hedgepeth

Electronic Thesis and Dissertation Repository

Titan is one of the most dynamic moons in the solar system. It is smaller than Earth and much colder, yet Titan is eerily similar to Earth, with rivers, rain, and seas, as well as sand seas that wrap around the equator. However, the rivers are made of hydrocarbons rather than water and the sand made of organics rather rock. We can use Titan’s impact craters to study how these processes modify the surface by comparing the craters depths, diameters and rim heights of Titan’s craters with fresh craters. Therefore, we have used the complete data set from ...


Serum Proteins In Healthy And Diseased Florida Manatees (Trichechus Manatus Latirostris), J.W. Harvey, K.E. Harr, D. Murphy, M.T. Walsh, M. de Wit, R.K. Bonde 2018 Department of Physiological Sciences, College of Veterinary Medicine, University of Florida,

Serum Proteins In Healthy And Diseased Florida Manatees (Trichechus Manatus Latirostris), J.W. Harvey, K.E. Harr, D. Murphy, M.T. Walsh, M. De Wit, R.K. Bonde

USGS Staff -- Published Research

A major goal of this study was to determine whether serum protein fractions of healthy Florida manatees differ with age, sex, or living environments (wild versus housed). A second goal was to determine which serum protein fractions vary in diseased versus healthy manatees. Serum protein fractions were determined using agarose gel electrophoresis. Healthy adults had slightly higher total serum protein and total globulin concentrations than younger animals. This largely resulted from an increase in gamma globulins with age. Total serum protein, albumin, alpha-1 globulin, beta globulin, and total globulin concentrations were slightly higher in housed manatees compared to wild manatees ...


Estimating Watershed Residence Times In Artificially-Drained Landscapes And Relation To Nutrient Concentrations, Emma Beck, Lisa Welp, Alexandra L. Meyer 2018 Purdue University

Estimating Watershed Residence Times In Artificially-Drained Landscapes And Relation To Nutrient Concentrations, Emma Beck, Lisa Welp, Alexandra L. Meyer

The Summer Undergraduate Research Fellowship (SURF) Symposium

Nutrient runoff from agricultural lands feeds harmful algae blooms that create a variety of problems in freshwater ecosystems. In order to reduce the effects of this nutrient runoff, Best Management Practices (BMPs) are being put in place in agricultural lands. Most of these BMPs focus on slowing down the flow of water through the watershed to give nutrient concentrations time to deplete before the water flows to the stream or river. However, the effectiveness of these BMPs are highly unknown and the process of monitoring nutrient runoff is often complex and costly. The data in this study consists of 7 ...


Remote Sensing Using I-Band And S-Band Signals Of Opportunity, Kadir Efecik, Benjamin R. Nold, James L. Garrison 2018 Purdue University

Remote Sensing Using I-Band And S-Band Signals Of Opportunity, Kadir Efecik, Benjamin R. Nold, James L. Garrison

The Summer Undergraduate Research Fellowship (SURF) Symposium

Measurement of soil moisture, especially the root zone soil moisture, is important in agriculture, meteorology, and hydrology. Root zone soil moisture is concerned with the first meter down the soil. Active and passive remote sensing methods used today utilizing L-band(1-2GHz) are physically limited to a sensing depth of about 5 cm or less. To remotely sense the soil moisture in the deeper parts of the soil, the frequency should be lowered. Lower frequencies cannot be used in active spaceborne instruments because of their need for larger antennas, radio frequency interference (RFI), and frequency spectrum allocations. Ground-based passive remote sensing ...


Remote Sensing Of Soil Moisture Using S-Band Signals Of Opportunity: Model Development And Experimental Validation, Marvin Jesse, Benjamin Nold, James L. Garrison 2018 Purdue University

Remote Sensing Of Soil Moisture Using S-Band Signals Of Opportunity: Model Development And Experimental Validation, Marvin Jesse, Benjamin Nold, James L. Garrison

The Summer Undergraduate Research Fellowship (SURF) Symposium

Root zone soil moisture (RZSM) is a vital aspect in meteorology, hydrology, and agriculture. There are currently some methods in passive and active remote sensing at L-band, but these methods are limited to a sensing depth of approximately 10 cm. Observing RZSM (water in the top meter of soil) will require lower frequencies, thus presenting significant difficulties for a spaceborne instrument, because of the required antenna size, the presence of radio-frequency interference (RFI), and competition for spectrum allocations (in the case of active radar). Bistatic radar using Signal of Opportunity (SoOp) (e.g. digital satellite transmitters) provides an opportunity for ...


Spatial Response Of Near-Surface Soil Water Contents To Newly Imposed Soil Management, Aaron L. M. Daigh, Upasana Ghosh, Jodi DeJong-Hughes, Robert Horton 2018 North Dakota State University--Fargo

Spatial Response Of Near-Surface Soil Water Contents To Newly Imposed Soil Management, Aaron L. M. Daigh, Upasana Ghosh, Jodi Dejong-Hughes, Robert Horton

Agronomy Publications

Near-surface soil water content (SWC) and its spatial patterns are important for landscape hydrological responses to precipitation as well as our ability to remotely sense and model such responses. Our objective was to measure and evaluate near-surface SWC semivariograms of agricultural fields with newly imposed (i.e., <2 yr) side-by-side soil and residue management practices (i.e., reduced tillage systems and cover crops) in the midwestern United States. Range parameters were consistently smaller when cover crops were planted (20–25 m less) and tillage area and/or intensity was reduced (12–27 m less) compared with no cover crop and chisel plowing, respectively, except in a clayey Vertisol. Nugget and sill parameters did not have consistent trends across soil management practices or sites. These data, although brief and preliminary in scope, provide clear proof of concept that spatial pattern shifts can be clearly detected in newly imposed soil-management systems even though differences in SWC means are not always evident.


Using Drones To Generate New Data For Conservation Insights, Paul Lorah, Alice Ready, Emma Rinn 2018 University of Saint Thomas

Using Drones To Generate New Data For Conservation Insights, Paul Lorah, Alice Ready, Emma Rinn

International Journal of Geospatial and Environmental Research

Human impact on the environment is driving a decline in biodiversity that heightens the need for informed management of conservation lands. Unmanned aerial vehicles (UAVs), also known as drones, are an increasingly cost-effective tool for generating high-quality data used to map landscape features, analyze land cover change and assess the effectiveness of conservation efforts. Traditional sources of remotely sensed data such as satellites and aircraft can be costly, inflexible and unable to detect fine-scale surface variation. This paper explores the advantages (and challenges) of analyzing data collected by drones to generate useful conservation management insights. We focus on three key ...


A Comparison Of Vnir And Mir Spectroscopy For Predicting Various Soil Properties, Joshua R. Gates 2018 University of Nebraska-Lincoln

A Comparison Of Vnir And Mir Spectroscopy For Predicting Various Soil Properties, Joshua R. Gates

Dissertations & Theses in Natural Resources

Soil plays an important role in our daily lives, namely producing food, cleaning water and storing carbon. The ability to rapidly and cost-effectively quantify the various components of soils can help us understand and better manage this important resource. This study aims to compare the ability of visible near-infrared (VNIR) spectroscopy and mid-infrared (MIR) spectroscopy to quickly and accurately predict various important soil properties (electrical conductivity, soil pH, cation exchange capacity, exchangeable cations, phosphorus, carbon, beta-glucosidase enzyme activity and nitrogen). Prediction models were developed using partial least squares regression (PLSR) techniques. Three different calibration sampling methods were tested along with ...


Boundary Spanners And Trust Development Between Stakeholders In Integrated Water Resource Management: A Mixed Methods Study, Jodi L. Delozier 2018 University of Nebraska-Lincoln

Boundary Spanners And Trust Development Between Stakeholders In Integrated Water Resource Management: A Mixed Methods Study, Jodi L. Delozier

Dissertations & Theses in Natural Resources

Natural resource issues are inherently complex, even more so are those that involve the management of water. Because watersheds tend to cross multiple jurisdictional and geographical boundaries, a diverse set of stakeholders are needed to develop appropriate and sustainable management policy. This research sheds light on the importance of boundary spanners assisting in the development of trust between stakeholders in integrated water resource management (IWRM). Previous literature has explored the advantages to boundary spanning leadership in business practice, emergency management, university and community management as well as fish and wildlife management, but has failed to address the area of integrated ...


Investigations Of The Potential For Irrigated Agriculture On The Bonaparte Plains: Bore Completion Report, D L. Bennett 2018 Department of Agriculture and Food, Western Australia

Investigations Of The Potential For Irrigated Agriculture On The Bonaparte Plains: Bore Completion Report, D L. Bennett

Resource management technical reports

Drilling programs were undertaken in 2013 and 2016 by the former Department of Agriculture and Food, Western Australia and in 2017 by DPIRD, at 10 sites in the Bonaparte Plains area, north of Kununurra in the East Kimberley region of Western Australia (WA).

These drilling programs were a component of resource availability and risk investigations conducted to determine the potential for developing irrigated agriculture on 30 000 hectares (ha) of Cockatoo Sands — free-draining loamy soils that have the potential to support crops in the wet and dry seasons. There was limited hydrogeological information available at a suitable scale for the ...


Geophysical Assessment Of Subsurface Soil Conditions Using Capacitively Coupled Resistivity, Folaseye Coker 2018 University of Arkansas, Fayetteville

Geophysical Assessment Of Subsurface Soil Conditions Using Capacitively Coupled Resistivity, Folaseye Coker

Theses and Dissertations

The purpose of this research is to explore the applicability of Capacitively-Coupled Resistivity (CCR) as an improvement on traditional drilling and sampling methods for subsurface soil investigations. The CCR method could be used to identify critical locations for drilling and sampling such as expansive clay layers and anomalies (sinkholes, unknown landfills, etc.) rather than uniformly sampling across a site. CCR surveys were performed at Alpena, Arkansas along a highway expansion project changing US 62 from a two lane to four lane highway, and at Alton, Illinois along the Mel Price Levee, a 5.2 mile levee along a portion of ...


Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd 2018 University of Arkansas, Fayetteville

Flow Regime Influences On Stream And Riparian Soil Carbon Dynamics In The Ozark Highlands And Boston Mountains Of Arkansas, Allyn Dodd

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 ...


A Quantitative Analysis Of Calcareous Nannofossils Across A Late Oligocene Paleolatitude Transect Of The North Atlantic Ocean, William Barrett Clark 2018 University of Nebraska-Lincoln

A Quantitative Analysis Of Calcareous Nannofossils Across A Late Oligocene Paleolatitude Transect Of The North Atlantic Ocean, William Barrett Clark

Dissertations & Theses in Earth and Atmospheric Sciences

Samples from ODP Sites 926, 628, 563, U1406, 647, and 918, were analyzed quantitatively across a paleolatitude transect of the North Atlantic Ocean to determine the paleolatitudinal distribution of calcareous nannofossils in the Late Oligocene and the effects of that distribution on biostratigraphic resolution. Detrended Correspondence Analysis (DCA), a Temperature index (TI), and the Shannon Diversity Index (H), were used to examine the paleoenvironmental gradients which exerted the most control over the distribution of species and their abundances. The temperature index correlates significantly to the first axis of the DCA, suggesting that thermal controls were the most important factor in ...


From Snow To Flow: Exploring Relationships Between Snotel Ablation Curves And Peak Streamflow Timing, Kara Jane Ferguson 2018 Boise State University

From Snow To Flow: Exploring Relationships Between Snotel Ablation Curves And Peak Streamflow Timing, Kara Jane Ferguson

Boise State University Theses and Dissertations

Predictions of peak streamflow timing in snow-dominated river systems are essential for proper water management and recreational availability. This study evaluates historic snow and streamflow data from 14 river basins throughout Idaho to investigate the relationship between snowmelt timing at SNOw TELemetry (SNOTEL) sites and peak streamflow within each basin. The goal is to provide a simple operational tool that estimates the probability of peak streamflow occurring within a certain number of days as ablation progresses from 0 to 100% melted. For individual basins we evaluate meltout levels in increments of 10% from each SNOTEL site and use a probabilistic ...


Exploring The Role Of Deforestation On Regional Hydroclimate In Southeast Africa: An Approach Fusing Models And Data, Megan Maksimowicz 2018 Boise State University

Exploring The Role Of Deforestation On Regional Hydroclimate In Southeast Africa: An Approach Fusing Models And Data, Megan Maksimowicz

Boise State University Theses and Dissertations

Land cover acts as the gatekeeper to incoming and outgoing energy and water fluxes at the land surface, partitioning energy and water in accordance with the vegetation type and in response to atmospheric forcings. As Land Surface Models become more complex and more capable of simulating the coupled dynamics of the land-atmosphere system in greater spatial detail, the need for accurate representation of spatial distribution of vegetation types and their dynamics through time grows.

As humans modify land cover, there are complex dynamics at play between the vegetation, the surface energy balance and the cycling of water. The resultant hydroclimatic ...


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