Geography Commons^™

Assessing, Restoring, And Centering Social–Ecological Relationships For Advancing Social–Ecological Resilience In The Northern Great Plains Grasslands, Katia Pilar Carranza Bernal

School of Natural Resources: Dissertations, Theses, and Student Research

The Northern Great Plains grasslands are social-ecological systems that were shaped by evolutionary and Indigenous social-ecological relationships. European colonization disrupted many of these interactions, including the coupling of fire and grazing, and degraded social-ecological resilience, shifting these grasslands to a new state. For those reasons, my research focused on assessing, restoring, and centering evolutionary and Indigenous social-ecological relationships for advancing social-ecological resilience in the Northern Great Plains grasslands. I first performed a study in the Nebraska Sandhillls assessing the potential of patch-burn grazing to support grassland resilience by comparing its effects to those of rotational grazing. Through vegetation and bird …

A Comparative Analysis Of Openet For Evaluating Evapotranspiration In California Almond Orchards, Kyle Knipper, Martha Anderson, Nicholas Bambach, Forrest Melton, Zac Ellis, Yun Yang, John Volk, Andrew J. Mcelrone, William Kustas, Matthew Roby, Will Carrara, Sebastian Castro, Ayse Kilic, Joshua B. Fisher, Anderson Ruhoff, Gabriel B. Senay, Charles Morton, Sebastian Saa, Richard G. Allen

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

The almond industry in California faces water management challenges that are being exacerbated by droughts, climate change, and groundwater sustainability legislation. The Tree-crop Remote sensing of Evapotranspiration eXperiment (T-REX) aims to explore opportunities to improve precision irrigation management for woody perennial cropping systems. Almond orchards in the California Central Valley were equipped with eddy covariance flux measurements to evaluate satellite remote sensing-based evapotranspiration (RSET) models. OpenET provides high-resolution (30-m spatial and daily temporal) RSET data, synthesizing decades of research for practical water management. This study provides an evaluation of OpenET performance at six almond sites covering a large range in …

Integrating Remote Sensing And Machine Learning To Determine Past, Current And Future Crop Water Use From The Nubian Sandstone Aquifer System, Moaz Ishag

Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research

The agriculture sector is a significant consumer of water, and sustainable water use begins with monitoring irrigated land. Delineating irrigated land supports decision-makers and promotes the sustainable use of this crucial resource. This study focuses on the Nubian Sandstone Aquifer System (NSAS), the largest aquifers in the world, which spans Egypt, Sudan, Libya, and Chad. The study aims to: 1) quantify the increase in irrigated hectares (both pivot and non-pivot) from 2000-2001 to 2023-2024; 2) identify major irrigated crop types and their water requirements; and 3) quantify groundwater crop water use from the NSAS using remote sensing via the Google …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle Duncan Dougherty

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Spatial Ecology Of Mountain Lions Throughout Their Distribution In California, Kyle D. Dougherty

School of Natural Resources: Dissertations, Theses, and Student Research

Mountain lions (Puma concolor) have been studied extensively throughout their wide geographic distribution in the Western Hemisphere, but most research has been conducted at relatively small spatial scales. We used GPS telemetry data contributed by researchers in 16 study areas throughout California to advance understanding of mountain lion spatial ecology. First, we investigated multi-scale resource selection of mountain lions relative to spatially varying risk of intentional human-caused mortality associated with livestock depredation management. We show that individuals that proactively avoided mortality risk when selecting home ranges were able to relax their avoidance of risk when making resource selection …

Uncovering The Dynamic Nature Of Fire Refugia Across Landscapes In Oregon's Western Cascades, Alec Scott Dyer

Dissertations and Theses

With increased fire activity, the presence of fire refugia is critical to support forest resiliency and mitigate large-scale vegetation conversion, however, the persistence of fire refugia within burn perimeters over time is uncertain. This study examines the dynamic nature of fire refugia by mapping the decline in forest cover over time, identifying spatiotemporal patch- and landscape-scale patterns and the biophysical drivers of delayed mortality following the 2020 Labor Day Fires occurring in Oregon’s western Cascades. After three years post-fire, delayed mortality accounted for an additional 8.5% of forest loss (total of 24,147 hectares in all five burns) compared to pre-fire …

The Ecosystem As Super-Organ/Ism, Revisited: Scaling Hydraulics To Forests Under Climate Change, Jeffrey D. Wood, Matteo Detto, Marvin Browne, Nathan J.B. Kraft, Alexandra G. Konings, Joshua B. Fisher, Gregory R. Quetin, Anna T. Trugman, Troy S. Magney, Camila D. Medeiros, Nidhi Vinod, Thomas N. Buckley, Lawren Sack

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Classic debates in community ecology focused on the complexities of considering an ecosystem as a super-organ or organism. New consideration of such perspectives could clarify mechanisms underlying the dynamics of forest carbon dioxide (CO₂) uptake and water vapor loss, important for predicting and managing the future of Earth's ecosystems and climate system. Here, we provide a rubric for considering ecosystem traits as aggregated, systemic, or emergent, i.e., representing the ecosystem as an aggregate of its individuals, or as a metaphorical or literal super-organ or organism. We review recent approaches to scaling-up plant water relations (hydraulics) concepts developed for …

Evidence Of Climatic Influence On Subsistence Strategies At Sage Hen Springs, Nevada, Andrew Rogers

Electronic Theses and Dissertations

Models of settlement patterns in the northwest Great Basin describe a decrease in residential mobility, intensified use of upland spring ecozones, and an increase in diet breadth during the Middle and Late Archaic. Here, I present data collected from the Sage Hen Springs site in northwestern Nevada during a Phase II testing project conducted by the BLM and an analysis of these data focusing on patterns of subsistence and mobility strategies throughout the Archaic. Results of this analysis support existing models of lifeways in the northwest Great Basin at the small scale and point to climatic factors as influences on …

Agricultural Groundcover Update May 2024, Justin Laycock

Natural resources published reports

• In May, over 9% (1,410,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.
• Northern grainbelt had the highest risk of wind erosion and over 26% of this farmland had inadequate groundcover, predominantly found on landscapes known for sandy soils.
• About 1.3% (208,900 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%. Half of this land was in the West Midlands Ag Soil Zone.

Agricultural Groundcover Update April 2024, Justin Laycock

Natural resources published reports

• In April, over 12% (1,876,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.
• Northern grainbelt had the highest risk of wind erosion and over 26% of this farmland had inadequate groundcover, predominantly found on landscapes known for sandy soils.
• About 1.5% (238,900 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.

Naturify 2300, Yarina Yiwei Dai

Masters Theses

In my art practice, I explore the interplay between human desires to manipulate and anthropomorphize nature, as seen in the technological augmentation of plants and living entities. This investigation delves into how this intersection, alongside empathy towards these creations, contributes to fears of uncontrollability and the risks of addiction and excessive dependence on technology.

Bioengineering and genetic modification have cultivated unprecedented developments, allowing humans to manipulate the fundamental building blocks of life. My research speculates on this technology further, modifying the genetic code of organisms and creating bioengineered wearable entities with enhanced traits or entirely new functionalities. The primary objective …

Du Undergraduate Showcase Abstracts: Research, Scholarship, And Creative Works, August Alexander, Kevin Summers, E. Paige Lloyd, Alyssa Aragon, Lauren Wols, Erica Larson, Colton Arciniaga, Lily Baeza, Ellie Barnett-Cashman, Sidney Barbier, Maverick Bartholomew, Ryan Bell, Trevor Briggs, Amanda Brown, Cory Marchi, Maddy Pontius, Jennifer Gallagher, Claire Kwok, Channing Bullock, Alex Mccollister, Kim Gorgens, Daniela Chavez, Yamilet Espinoza Nuñez, Giovanni Valladares Giron, William Christensen, Olivia Kachulis, Daniel Cierasynski, Brandon Cohen, Spenser Dobbs, Lindsay Goolsby, Noah Craver, Nyah Cubbison, Liam Doherty, Nicole Doris, Yan Qin, Alexander Nguyen, Lily Harmon, Shubh Todi, Naichen Zhao, Noah Fagello, Stacia Fritz, Paola Gascot-Chinea, Alex Volkova, Janelyn Geronimo, Elsie Harrington, Shane Simmons, Clarice Hise, Laura Moreno Palmer, Henry Xu, Yesu Leela Pasupula, Emily Fisher, Zachary Hogan, Colin Kleckner, Alyssa Knaus, Erin Kubat, Sam Werkema, Katie Lamberton, Lilliya Larson, Allie Leary, Vanessa Leon-Gamez, James H. Gallagher, E. Dale Broder, Robin M. Tinghitella, Emma Loeber, Alina Mali, Ixchel Marquez, Lauren Mcgrath, Ella Matthews, Grace Naegelen, Audrey Ng, Megan Lucyshyn, Rachel Brough, Alexandra Norman, Joe Ontiveros Rodriguez, Ben Dossett, Ori Miller, Janamejay Sharma, Christopher Reardon, Vincent Pandey, Regan Parish, Ren Pratt, Alisha Pravasi, Sanchari Das, Cari Reichel, Emma Robson, Victoria Rockwell, Jayce Rumsey, Steven Said, Norah Schroder, Alaina Smith, Shannon Murphy, Shujan A. Sharafeldeen, Stanley M. Kanai, James T. Nichols, David E. Clouthier, Macalia R. Augustus, Daniel Silva Rios, Scott Simpson, Anna Sparling, Chase Spurbeck, Kimberly Chiew, Christine Stadnik-Poteroba, Jacqueline Stephenson, Evelyn Stovin, Mia Supan, Lauren Tapper, Will Thrush, Anna Vogt, Michaela Walheim, Jon Weber, Hunter Whitehouse, Kansas Wood, Hayley Sayre, Lydia Mccann, Maread Mclaughlin, Kelly Krumrie, Olivia Wuttke

DU Undergraduate Research Journal Archive

Abstracts from the DU Undergraduate Research Showcase.

From Pixels To Plants: Remote Sensing Of California Invasive Plants, Kenneth Rangel

Master's Projects and Capstones

Invasive plants cause significant impacts to ecosystems, the economy, and human health. California has experienced significant plant invasions and is well suited to future invasion because of its Mediterranean climate and human disturbance. Eradication or control of invasive plant species requires a detailed understanding of their spatial distribution, which typically involves on the ground surveys that can be expensive or inconsistent. Remote sensing offers a potential alternative or supplement to in-person invasive plant mapping. This study performed a comparative analysis of 41 remote sensing studies that mapped the distribution of California invasive plants. I found that while high spectral resolution …

Managing The Environmental And Socio-Economic Impacts Of Rohingya Refugees In Bangladesh, Mousume Azad

Master's Projects and Capstones

In August 2017, nearly 1 million Rohingya people fled to Bangladesh to save their lives from the genocide inflicted by the military of Myanmar. At present, over 1.3 million Rohingyas are staying at Cox’s Bazar, Bangladesh, in 34 overcrowded refugee camps. This research examined the environmental impacts especially the change in vegetation cover and land surface temperature as well as the socioeconomic alteration of the host country after the refugee influx. The research found a 5488 ha or 9.58% decrease in forest area, accompanied by an 8.25% increase in refugee settlement areas, an increase in average land surface temperature within …

Impact Of Temperature On Children’S Nutrition: A Comparative Study Of Three Ecological Regions Of Nepal, Prakriti Shakya

Master's Theses

Nutrition obtained during the growth period of childhood significantly influences long-term well-being and overall productivity, ultimately contributing to the economy of a society. However, weather shocks can wreak havoc by damaging crops, changing yields of important crops and disrupting market access, which directly impacts the food intake of both adults and children. When these adverse events occur during childhood, short term and long term inadequacy in nutrition as well as disease incidence can cause malnutrition leading to stunted growth and cognitive impairment that may persist into adulthood, affecting the labor market and increasing health expenditure. To address this issue, we …

Land Use Intensification And Bio-Resource Utilisation In The South Pacific Islands, David Lopez Cornelio

International Journal of Islands Research

The long and gradual colonisation of the Pacific islands created settlements of cohesive social networks that fused or were displaced by western ways of life, trade and governance through the centuries. In this paper, a historical review of the processes of island discovery, plants domestication, and of land use practices are discussed alongside the main socioeconomic drivers of land cover change. The native trees of the South Pacific constitute an invaluable resource for sustainable development; they were used and domesticated for thousands of years but logging, commercial agriculture, mining, the introduction of exotic species and urban expansion are threatening them …

Dendrochronological Analysis Of The Duncan Tavern, Paris, Kentucky, Usa, Delaney Ballard, Maegen Rochner

Undergraduate Research Events

Duncan Tavern is a historical structure located at 323 High Street in Paris, Kentucky in Bourbon County. The structure currently serves as the headquarters for the Kentucky Society of the Daughters of the American Revolution (KSDAR). KSDAR maintains that Duncan Tavern was originally built in the mid-1790s; the land was purchased in 1792 by Joseph Duncan, a civilian armorer in the Revolutionary War. Although Duncan Tavern has been listed on the National Register of Historical Places since 1973, a dendrochronological study of this structure was requested to quantitatively examine the legitimacy of archival and anecdotal claims about the construction history. …

Thematic Mapping Of Apidae Holdings Within The University Of Arkansas Arthropod Museum, Baylie Lenora Day

Crop, Soil and Environmental Sciences Undergraduate Honors Theses

Museum biological collections store species data that can be utilized in research on biodiversity, environmental change, invasive species, public health, and disease. The University of Arkansas Arthropod Museum, which began in 1905, houses over 750,000 specimens and has not yet been digitized. Making data publicly accessible via the internet makes the data available to the entire scientific community. The goal of this project was to create a digital resource to allow greater access to the University of Arkansas Arthropod Museum holdings. To do so, data from Bombus (bumble bee) and Xylocopa (carpenter bee) specimens were databased in Excel and displayed …

What's In A Name? Plant Naming As Cultural Artifact And Story In The Midwestern United States, Sophie Wesseler

Undergraduate Theses

This project sought to collect and contextualize the historical and contemporary names given to plants by inhabitants of the Midwestern United States, understanding plant names as cultural artifacts that can offer insight into the communities in which they were created and evolved. Formatted as a series of entries, this collection gathered these names and contextualized them within other artifacts of cultural significance, such as art or poetry, and alongside historical research on their origins and cultural environments. Examining plant names through the fields of linguistics, semiology, anthropology, cultural studies, taxonomy, and ethnobotany, this work traces the names of various plants …

College Of Natural Sciences Newsletter, Spring 2024, College Of Natural Sciences

College of Natural Sciences Newsletters and Reports

Page 1 Dean's Message
Page 2 New Faculty and New Club on Campus
Page 3 2024 URSCAD Awards
Page 4 Day of Scholars 2024
Page 5 SDSU's First Representation at the Association for Anatomy's 2024
Annual Conference
Page 6-7 2024 Honor's College Convocation
Page 8 Other Student Activities
Page 9 Faculty Awards
Page 10-11 Other News
Page 12 2024 Drone Day and American Association of Geographers Convention - Hawaii
Page 13 55th Annual Geography Convention
Page 14 2024 Stethoscope Ceremony
Page 15 Open PRAIRIE Data

Agricultural Groundcover Update March 2024, Justin Laycock

Natural resources published reports

• In March, over 10% (1,577,000 ha) of the arable farmland in the south-west of Western Australia had less than 50% vegetative groundcover, which is inadequate to prevent wind erosion.

• The northern grainbelt had the highest risk of wind erosion and over 20% of this farmland had inadequate groundcover.

• About 1.3% (191,000 ha) of arable land had a high to very high risk of wind erosion because groundcover was less than 30%.

Microwave Emission Model Parameter Tuning For Surface Soil Moisture Retrieval Using Uav-Mounted Dual Polarization L-Band Radiometer, Santiago Hoyos Echeverri

Open Access Theses & Dissertations

Surface soil moisture retrieval from L-band brightness temperature has been developed for the past decades due to multiple beneficial characteristics of 1-2 GHz frequency bands for remote sensing of the environment. Numerous microwave emission models have been proposed for tower and satellite-based operations with successful retrieval of surface soil moisture and vegetation water content. As a result of the development of cost-effective and low-mass microwave L-band radiometers such as the Portable L-band Radiometer (PoLRa), surface soil moisture surveying traditionally developed by satellite missions SMOS and SMAP can now be developed at local scales, bringing these operations to commercial small unmanned …

Examining Context Dependency Of Invasion Hypotheses At The Continental Scale Using Riverine Fish Communities, Lily Thompson

All Dissertations

Many well-supported hypotheses seek to explain invasion dynamics, but evidence for common patterns among regions and taxa remains inconclusive and often contradictory. Invasion ecology is fundamentally linked to spatial scale, and discrepancies in results among invasion studies may be attributed, in part, to a failure to fully consider scale dependency. In this dissertation, I investigate the sources of inconsistencies across spatial scales and large geographic extents using riverine fish communities across the conterminous United States. To do so, I tested three main ideas. First, that cross-scale interactions contextualize estimated invasion mechanisms among regions. My results demonstrate that local empirical support …

Net Fluxes Of Broadband Shortwave And Photosynthetically Active Radiation Complement Ndvi And Near Infrared Reflectance Of Vegetation To Explain Gross Photosynthesis Variability Across Ecosystems And Climate, Kanishka Mallick, Joseph Verfaillie, Tianxin Wang, Ariane Arias Ortiz, Daphne Szutu, Koong Yi, Yanghui Kang, Robert Shortt, Tian Hu, Mauro Sulis, Zoltan Szantoi, Gilles Boulet, Joshua B. Fisher, Dennis Baldocchi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

A significant challenge in global change research is understanding how vegetation interacts with the environment to influence ecosystem gross primary productivity (GPP) through carbon assimilation. One emerging objective is to consistently predict GPP fluctuations worldwide by establishing a robust scaling relationship between GPP measured at flux towers and satellite spectral reflectance data. However, a major hurdle in achieving this goal is the discrepancy in spatial resolution between early satellite measurements and eddy flux measurements. By using a large set of growing season data covering 100 site-years in North and Central America, we explored the potential of transforming incident and reflected …

Agricultural Groundcover Update February 2024, Justin Laycock

Natural resources published reports

• About 92% of the grainbelt had adequate (more than 50%) vegetative groundcover to prevent wind erosion in February 2024.

• Nearly 8% of the grainbelt (1,193,400 ha) had less than 50% groundcover, which is inadequate to prevent wind erosion.

• The northern grainbelt had the highest risk of wind erosion and 16.5% of this farmland had inadequate groundcover.

• Less than 0.7% of the grainbelt had a high to very high risk of wind erosion because groundcover was less than 30%.

Maize Production In Ghana: A Case Study Of Asante Akim North Municipality, Vincent Osei

Masters Theses

In spite of the numerous benefits of maize production in Ghana, its production is faced with a lot of challenges leading to production losses. Asante Akim North Municipality is one of the largest maize-producing areas in Ghana. However, studies on maize and its production in this municipality are under-researched, hence the need for this study. The main objective of the study is to analyze a 10-year (2013-2022) production trend of maize in Asante Akim North Municipality to identify factors affecting maize production in the municipality, so as to seek pragmatic measures to help improve maize yields in the municipality and …

Mushroom Composition Across An Elevational Gradient During The 2024 Wet Season In Mazumbai Forest Reserve, Tanzania, Christopher Brady

Independent Study Project (ISP) Collection

Mushrooms are key bioindicators that contribute greatly to ecological health, and their diversity is indicative of a healthy ecosystem. However, even with the vital role they play in ecological health, there are few studies which measure the diversity of mushrooms in Mazumbai Forest Reserve (MFR), Tanzania, Africa, and none which focus on diversity along the elevational gradient within the reserve (1300-1900m). This study measures the diversity and equitability of mushrooms growing in six elevational zones within MFR during the rainy season of 2024. A species checklist of mushrooms growing in MFR during the 2024 rainy season was created, tracking the …

Evaluating The Environmental Impacts Of U.S. Historical Oil Spill Incidents, Yiming Liu, Hua Cai

Graduate Industrial Research Symposium

Exposure to risks associated with the production and usage of products, particularly oil, poses significant threats to both ecological systems and human health. Notable examples include the Gulf War Oil Spill (1991) and the Deepwater Horizon Oil Spill (2010). However, numerous smaller-scale oil spills, which collectively contribute to substantial oil releases, often remain overlooked. To fill this gap, our study first developed a detailed oil spill incidents database, covering 1967 to 2023. We quantified the released amount (RA) of oil spills recorded by the National Oceanic and Atmospheric Administration (NOAA). Subsequently, we utilized life cycle impact indicators in ReCiPe to …

Design And Test The Effectiveness Of Interpretive Signs Using Eye Tracking And Biometric Data, Hadara Gordon, Wendy Miyazaki

Baker/Koob Endowments Awarded Projects

Recreational trails on forested lands should satisfy the needs of recreationists, safeguard important habitats, and maintain the natural environment (Kortenkamp et al., 2021). Appropriate management is critical because of the increasing number of visitors. Signs are a cost-effective method to reduce the negative impacts on visitors and enhance visitor experiences (Brown et al., 2010). This research aimed to investigate how visitors pay attention to signs, view the trail surrounded by trees and behave in a natural space.

Integrating Multiscale Geospatial Analysis For Monitoring Crop Growth, Nutrient Distribution, And Hydrological Dynamics In Large-Scale Agricultural Systems, Olatunde D. Akanbi, Deepa C. Bhuvanagiri, Erika I. Barcelos, Arafath Nihar, Brian Gonzalez Hernandez, Jeffrey M. Yarus, Roger H. French

Faculty Scholarship

Monitoring crop growth, soil conditions, and hydrological dynamics are imperative for sustainable agriculture and reduced environmental impacts. This interdisciplinary study integrates remote sensing, digital soil mapping, and hydrological data to elucidate intricate connections between these factors in the state of Ohio, USA. Advanced spatiotemporal analysis techniques were applied to key datasets, including the MODIS sensor satellite imagery, USDA crop data, soil datasets, Aster GDEM, and USGS stream gauge measurements. Vegetation indices derived from MODIS characterized crop-specific phenology and productivity patterns. Exploratory spatial data analysis show relationships of vegetation dynamics and soil properties, uncovering links between plant vigor, edaphic fertility, and …