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Full-Text Articles in Natural Resources Management and Policy

Targeting Macrophytes: Increased Water Quality Through Optimized Vegetation Considerations For Constructed Wetlands, Austin Mcbrady Dec 2023

Targeting Macrophytes: Increased Water Quality Through Optimized Vegetation Considerations For Constructed Wetlands, Austin Mcbrady

Masters Theses

This study of constructed wetland design investigated relationships between macrophyte species selection and planting density for water quality improvement. A lab-scale wetland was compared against a pilot-scale wetland in San Antonio, Texas at Mitchell Lake to measure differences in effluent water quality improvement using three native macrophyte species. Using a novel, two-phase method, a targeting macrophyte was identified from among other species based on its marked capability for improving water quality factors, then was planted in varied majority densities to compare differences in treatment effectiveness. The results of this study showed that this complimentary approach to wetland design displayed significant …


Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin Sep 2023

Fire Effects On Soil Organic Matter In The Creek Fire, Gracie E. Doolin

Master of Science in Environmental Sciences and Management Projects

Wildfires have increased in frequency and severity over the past few decades due to the increased concertation of CO2 emissions from anthropogenic influence. Soil carbon (C) sequestration has been identified as a climate change mitigation strategy; however, the influx of large-scale wildfires has accelerated landscape processes such as erosion, reducing soil aggradation, and soil C and nitrogen (N) protection. This trend is highlighted by the Creek Fire that occurred in September 2020 and burned 379,895 acres in the Sierra National Forest. This research is designed to close the knowledge gap regarding the impact of burn severity on soil organic matter …


Pumping-Induced Drawdown Of Streams In Proximity To Agricultural Wells, Sara Alina Sternberg Sep 2023

Pumping-Induced Drawdown Of Streams In Proximity To Agricultural Wells, Sara Alina Sternberg

Master of Science in Environmental Sciences and Management Projects

In the context of unprecedented drought and aquifer overdraft in California, understanding surface water and groundwater connectivity have become increasingly important. While there is a clear understanding of how wells induce drawdown in aquifers (Theis, 1935; Hantush, 1965), secondary effects on local streams have not fully been considered. Current mathematical models targeting aquifer drawdown do not address stream drawdown response in aquifer-stream systems with strong connectivity; instead, they assume the stream to be a constant head boundary. In the drought-stricken and summer-dry climate of California, streams often run dry for months out of the year, which is currently not reflected …


Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed Aug 2023

Analyzing The Adoption, Cropping Rotation, And Impact Of Winter Cover Crops In The Mississippi Alluvial Plain (Map) Region Through Remote Sensing Technologies, Zobaer Ahmed

Graduate Theses and Dissertations

This dissertation explores the application of remote sensing technologies in conservation agriculture, specifically focusing on identifying and mapping winter cover crops and assessing voluntary cover crop adoption and cropping patterns in the Arkansas portion of the Mississippi Alluvial Plain (MAP). In the first chapter, a systematic review using the PRISMA methodology examines the last 30 years of thematic research, development, and trends in remote sensing applied to conservation agriculture from a global perspective. The review uncovers a growing interest in remote sensing-based research in conservation agriculture and emphasizes the necessity for further studies dedicated to conservation practices. Among the 68 …


Evaluation Of Hydrogeochemical Characteristics Of San Joaquin, Tulare, And Mojave Aquifers, Southern California, Maedeh Hassanvand May 2023

Evaluation Of Hydrogeochemical Characteristics Of San Joaquin, Tulare, And Mojave Aquifers, Southern California, Maedeh Hassanvand

Graduate Theses and Dissertations

Before making attempts to enhance and manage the quality of water, a thorough understanding of these processes is necessary since the chemical quality of groundwater is impacted by a number of linked processes. This would be more important in arid and semiarid regions like the southern part of California where more rely on groundwater for agriculture and drinking water uses than the other states. As a result, fundamental knowledge of the governing processes of groundwater chemistry is required for effective water resource management. Thus, this study is primarily concerned with three aspects in Mojave, Tulare, and San Joaquin aquifers: The …


Assessing Ecosystem Health Through Contaminants In The Tijuana River National Estuarine Research Reserve, Nancy Torres Jan 2023

Assessing Ecosystem Health Through Contaminants In The Tijuana River National Estuarine Research Reserve, Nancy Torres

Theses

Although the Tijuana River Estuary (TRE) remains the largest, most-intact coastal wetland in Southern California, it has a history of major changes, much of this related to its location immediately north of the US / Mexico Border. One of the primary challenges is cross-border flows from the rapidly growing city of Tijuana, Baja California, Mexico, and the delivery of wastewater, debris, and sediment to sensitive coastal wetland ecosystems. There is a need to more fully investigate these environmental changes to assess the ecosystem health of the Tijuana River Estuary over time, especially related to pollution impacts. This can inform an …


National Development And The Sustainability Of Mining In The Atacama Desert, Chile, Dakota Soleil Osgood Jan 2023

National Development And The Sustainability Of Mining In The Atacama Desert, Chile, Dakota Soleil Osgood

Capstone Collection

As climate change continues to intensify on a global scale, efforts have been made to implement renewable energies and progressive technologies. These tools are critical in the shift towards a more sustainable practice, and yet analysis of localized impacts from the development of these mechanisms is inadequate. Chile has been and continues to be a leading country in mineral extraction, with an economic history founded in the mining industry. The establishment of mining in Chile as a progressive tool has aided the social and economic development of the nation. Consequences of mining extraction, however, include intensive environmental degradation, human rights …


Power Play: The President's Role In Shaping Renewable Energy Regulation And Policy, Luke Bartol Jan 2023

Power Play: The President's Role In Shaping Renewable Energy Regulation And Policy, Luke Bartol

Honors Projects

With the impacts of climate change becoming more and more apparent every day, finding means of effective action to mitigate its effects become increasingly critical. While localized work can play an important role, federal action is necessary to have the most widespread and effective impact, especially on interconnected issues such as clean energy. Congressional action is the avenue of change at this level, however in an increasingly partisan and divided environment, progress on this front is far short of what is needed.

Looking to the president is logical here, both as a single actor more insulated from partisan fights, but …


Field Tests Of A Uav-Compatible Spectrometer To Evaluate Its Suitability For Detailed Soil Radon Potential Mapping, Alexandria Briahnne Thomas Jan 2023

Field Tests Of A Uav-Compatible Spectrometer To Evaluate Its Suitability For Detailed Soil Radon Potential Mapping, Alexandria Briahnne Thomas

Theses and Dissertations--Earth and Environmental Sciences

As part of ongoing research on radionuclide mapping and radon hazard characterization, field tests were performed to evaluate the suitability and limitations of a UAV-compatible gamma spectrometer. To date, this data set includes completed stationary data collection, mobile ground collection, multi-level UAV flights over a known material transition, as well as redundant ground and multi-level UAV data collection over a relatively uniform area. Total counts were used as a measure of soil radionuclide levels for our data collected above background. Although our test sites were in regions underlain by bedrock with high indoor radon levels, uranium counts were barely above …


Analysis Of Benthic Macroinvertebrate Response To Restoration Flows And Scour In The Trinity River, Northern California, Sarah Gutierrez, Julie Avina Jan 2023

Analysis Of Benthic Macroinvertebrate Response To Restoration Flows And Scour In The Trinity River, Northern California, Sarah Gutierrez, Julie Avina

Cal Poly Humboldt Capstone Honor Roll

This study investigates the ecological impact of restoration flows and scouring events on benthic macroinvertebrate (BMI) communities within the Trinity River, an ecosystem historically impacted by anthropogenic activities. Central to this study is the examination of how hydrologic alterations, especially the construction of the Lewiston Dam, have influenced these vital ecological indicators. Using data collected earlier in 2023 from a current study by Benjamin King, we analyzed BMI samples from three river sites (Junction City, Pear Tree, and Lorenz Gulch), both prior to and following a major scouring event in January 2023. This paper utilizes statistical analyses, including ANOVA and …