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Environmental Indicators and Impact Assessment
School of Natural Resources: Dissertations, Theses, and Student Research
- Keyword
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- Agriculture (3)
- Climate (2)
- Cyanobacteria (2)
- Phytoplankton (2)
- Abundance estimation (1)
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- Adaptation (1)
- Africa (1)
- Alaska (1)
- Aluminum sulfate (1)
- Arcgis (1)
- Arcgis pro (1)
- Beef (1)
- Biofuel (1)
- Biofuels (1)
- Biological monitoring (1)
- Bos gaurus (1)
- Botswana (1)
- Camera trapping (1)
- Climate Change (1)
- Climate change (1)
- Conservation (1)
- Corn (1)
- Crop yield (1)
- Drought (1)
- Emissions (1)
- Eutrophication (1)
- Evapotranspiration (1)
- GIS (1)
- GRACE; Drought stress ;Tree rings; Forest (1)
- Gaur (1)
Articles 1 - 16 of 16
Full-Text Articles in Physical Sciences and Mathematics
Connecting The Nebraska Water Quality Index To The Aquatic Microbial Community Of The North Platte River Basin, Nebraska, Paula R. Guastello
Connecting The Nebraska Water Quality Index To The Aquatic Microbial Community Of The North Platte River Basin, Nebraska, Paula R. Guastello
School of Natural Resources: Dissertations, Theses, and Student Research
The Nebraska Water Quality Index, under development by the Nebraska Department of Environment and Energy, summarizes in a single value eight environmental parameters that have been monitored in Nebraska for nearly 20 years. Water quality parameters including those used in the Nebraska Water Quality Index have been shown in previous studies to impact bacterial growth. As such, this index has the potential to correlate with the freshwater microbial community. Here, I relate the Nebraska Water Quality Index to microbial community composition and structure using 16S rRNA gene amplicon sequence data collected from the North Platte River Basin, Nebraska. This index …
The Last Drought Frontier: Building A Drought Index For The State Of Alaska, Olivia Campbell
The Last Drought Frontier: Building A Drought Index For The State Of Alaska, Olivia Campbell
School of Natural Resources: Dissertations, Theses, and Student Research
Drought is characterized by periods of below average precipitation. There are five major types of drought recognized in the literature: meteorological, hydrological, agricultural, socioeconomic, and ecological. A relatively new concept in the drought literature is “snow drought.” A key part of the definition of drought is that it is not always accompanied by extreme heat. This means drought can occur even in cold climates, cold seasons, and higher latitudes and altitudes, like Alaska. Drought is a natural part of climate variability, but Alaska’s climate is changing faster than any other state in the United States. Alaska is no stranger to …
Multi-Criteria Evaluation Model For Classifying Marginal Cropland In Nebraska Using Historical Crop Yield And Biophysical Characteristics, Andrew Laws
School of Natural Resources: Dissertations, Theses, and Student Research
Marginal cropland is suboptimal due to historically low and variable productivity and limiting biophysical characteristics. To support future agricultural management and policy decisions in Nebraska, U.S.A, it is important to understand where cropland is marginal for its two most economically important crops: corn (Zea mays) and soybean (Glycine max). As corn and soybean are frequently planted in a crop rotation, it is important to consider if there is a relationship with cropland marginality. Based on the current literature, there exists a need for a flexible yet robust methodology for identifying marginal land at different scales, which …
Comprehensive And Agricultural Greenhouse Gas Emissions Inventories For Nebraska And The Midwest As Baselines For Climate Change Mitigation, Eric R. Holley
Comprehensive And Agricultural Greenhouse Gas Emissions Inventories For Nebraska And The Midwest As Baselines For Climate Change Mitigation, Eric R. Holley
School of Natural Resources: Dissertations, Theses, and Student Research
Climate change is the paramount challenge of today for a sustainable future. Mitigation of greenhouse gas (GHG) emissions is necessary to reduce the associated risks and impacts on society. Using the EPA’s SIT and literature review, comprehensive GHG-emissions inventories were developed for the state of Nebraska over 25 years (1990-2015) and agricultural GHG emissions inventories were developed for the Midwest U.S for one year (2016). Nebraska’s net emissions increased from 56.2 million metric tons of carbon dioxide equivalent (MMtCO2e) in 1990 to 87.4 MMtCO2e in 2016. Agriculture was found to be the sector with the most …
Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang
Investigation Of Grace-Derived Information On Forest Drought Stress Across The Contiguous Us, Beichen Zhang
School of Natural Resources: Dissertations, Theses, and Student Research
This research derives z-score monthly groundwater storage (GWS) anomalies and z-score monthly root zone soil moisture (RZSM) anomalies from products of Gravity Recovery and Climate Experiment Data Assimilation (GRACE-DA). Z-score monthly GWS and RZSM anomalies are compared to two drought indicators: Standardized Precipitation Index (SPI) and Standardized Precipitation-Evapotranspiration Index (SPEI) to investigate the usefulness of GRACE-DA information to detect drought conditions at tree-ring sites. This study also compares z-score monthly GWS and RZSM anomalies with the Tree Ring Standardized Growth Index (TRSGI) that is resampled by bootstrapping to investigate the capability of monitoring forest drought stress. Finally, this research uses …
Assessing Responses Of Betula Papyrifera (Paper Birch) To Climate Variability In A Remnant Population Along The Niobrara River In Nebraska Through Dendroecological And Remote Sensing Techniques, Evan Bumann
School of Natural Resources: Dissertations, Theses, and Student Research
Remnant populations of the boreal species Betula papyrifera, found along north-facing canyons and river banks of the Niobrara River Valley in north-central Nebraska, represent one of the southernmost distributions of the species in North America. Although, the species has persisted in the Great Plains after the Wisconsin Glaciation due to the local topography and microclimatic conditions, canopy dieback has been reported in recent years, which is believed to be attributed to temperature change. Therefore, the goals of this research are to: 1) use dendroecological techniques, or the study of tree rings to assess the responses B. papyrifera to intra- and …
Applications Of Time-Lapse Imagery For Monitoring And Illustrating Ecological Dynamics In A Water-Stressed System, Emma Brinley Buckley
Applications Of Time-Lapse Imagery For Monitoring And Illustrating Ecological Dynamics In A Water-Stressed System, Emma Brinley Buckley
School of Natural Resources: Dissertations, Theses, and Student Research
Understanding and perceiving the natural world is a key part of management, policy, conservation, and inevitably for our future. Increased demand on natural resources has heightened the importance of documenting ecosystem changes, and knowledge-sharing to foster awareness. The advancement of digital technologies has improved the efficiency of passive monitoring, connectivity among systems, and expanded the potential for innovative and communicative approaches. From technological progression, time-lapse imagery has emerged a valuable tool to capture and depict natural systems. I sought to enhance our understanding of a water-stressed system by analyzing imagery, in addition to integrating images with data visualization to illustrate …
Gaur (Bos Gaurus) Abundance, Distribution, And Habitat Use Patterns In Kuiburi National Park, Southwestern Thailand, Supatcharee Tanasarnpaiboon
Gaur (Bos Gaurus) Abundance, Distribution, And Habitat Use Patterns In Kuiburi National Park, Southwestern Thailand, Supatcharee Tanasarnpaiboon
School of Natural Resources: Dissertations, Theses, and Student Research
Population status of gaur (Bos gaurus), a wild cattle, in most habitats where they are present, is still unknown. As the use of camera traps in wildlife studies are widespread, I developed photographic individual identification procedures and utilized encounter histories of gaur individuals from camera trap data to estimate gaur abundance and density using the spatially explicit capture-recapture analysis. The study was conducted at Kuiburi National Park, southwestern Thailand, comprised of dry evergreen forest, moist evergreen forest, and man-modified secondary forest during November 2013- January 2015. I conducted 71 direct observations in a savannah-like habitat area to observe …
Occupancy Analysis And Density Estimation Of Kori Bustards (Ardeotis Kori) And Helmeted Guineafowl (Numida Meleagris) For Use In Landscape Conservation Planning In The Northern Tuli Game Reserve, Botswana, Kathryn R. Mccollum
School of Natural Resources: Dissertations, Theses, and Student Research
For understudied species, more informed conservation planning and decision-making on both the local and landscape levels may be attained through the use of occupancy and abundance estimations. Here, we focus on two iconic bird species in eastern Botswana, kori bustards (Ardeotis kori) and helmeted guineafowl (Numida meleagris). The overall goal of this project was to better understand the hierarchy of factors that influence occupancy (ψ) and density of kori bustard and helmeted guineafowl populations within the Northern Tuli Game Reserve and how these factors may interact to affect landscape conservation and usage. We performed distance sampling …
Shorebird Migratory Stopover Responses To Local And Regional Change: Habitat Decisions In A Vanishing Landscape, Caitlyn Gillespie
Shorebird Migratory Stopover Responses To Local And Regional Change: Habitat Decisions In A Vanishing Landscape, Caitlyn Gillespie
School of Natural Resources: Dissertations, Theses, and Student Research
Understanding the consequences of anthropogenic change for migratory species is challenging because although they have evolved to cope with environmental uncertainty, migrants still rely on predictable relationships within and among habitats to make informed decisions. Calidris shorebirds rely on ephemeral wetlands during northward migration through mid-continental North America, where favorable habitat conditions are annually and regionally unpredictable and increasingly altered by land-use change. During spring 2013 and 2014, we assessed Calidris habitat use in the Rainwater Basin (RWB) and the Prairie Pothole Region (PPR) at both local and landscape scales. Although anthropogenic change has altered the wetland landscape in both …
Genetic And Morphological Variation In Ecuadorian Astroblepid Catfishes, Katherine M. Lawry
Genetic And Morphological Variation In Ecuadorian Astroblepid Catfishes, Katherine M. Lawry
School of Natural Resources: Dissertations, Theses, and Student Research
The Andean ichthyofauna remains a poorly understood component of Neotropical biodiversity, and stands in stark contrast to the lowland ichthyofauna in terms of number of species and range of distribution. The Climate Variability Hypothesis (CVH) predicts rapid turnover of species along elevational gradients in tropical climates, but it remains unclear whether stream fishes follow this pattern. Astroblepid catfishes represent a distinctive assemblage of species that inhabit high elevation streams throughout the Andes from Panama to Bolivia, and constitute the only native fish family present in the Ecuadorian highland region. In this research, population samples of Astroblepids collected throughout Ecuador’s Napo …
Combating Eutrophication: An Ecosystem Scale Analysis Of Aluminum Sulfate (Alum) Effectiveness Among Lakes, With Comparison To Alum And Biomanipulation Dual Treatment, Christa M. Webber
Combating Eutrophication: An Ecosystem Scale Analysis Of Aluminum Sulfate (Alum) Effectiveness Among Lakes, With Comparison To Alum And Biomanipulation Dual Treatment, Christa M. Webber
School of Natural Resources: Dissertations, Theses, and Student Research
Eutrophic conditions in lakes and reservoirs in agricultural regions often drive summer blooms of toxic cyanobacteria. Aluminum sulfate (alum) applications are commonly used to control cyanobacteria blooms and restore water quality in eutrophic lakes. However, studies of alum treatments often lack true replication, comparison to reference lakes, or comparison to other restoration techniques, such as an alum and biomanipulation combined or “dual” treatments. Without these comparisons, the variation of treatment response between replicate lakes and restoration techniques remains uncertain. Therefore, I sought to assess how water quality is affected by multiple restoration techniques among geographically proximate (1.4 km2) …
Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander
Interactions Of Zooplankton And Phytoplankton With Cyanobacteria, Rebecca Alexander
School of Natural Resources: Dissertations, Theses, and Student Research
Cyanobacteria are a major concern in Nebraska reservoirs and are capable of producing toxins that can cause skin irritations and gastrointestinal problems, as well as affect the nervous system. It is important to determine the mechanisms that can cause cyanobacteria blooms due to the effect they can have on human health. The interaction of zooplankton and other phytoplankton groups with cyanobacteria is important because there is a biological component in surface waters that should be taken into consideration along with the physical and chemical parameters that have been noted to promote cyanobacteria. For example, zooplankton have the ability to alter …
Impacts Of Climate Change On The Surface Water Balance Of The Central United States, 1984-2007, Bo Dong
Impacts Of Climate Change On The Surface Water Balance Of The Central United States, 1984-2007, Bo Dong
School of Natural Resources: Dissertations, Theses, and Student Research
The climate system and the hydrologic cycle are strongly connected with each other. Understanding the interactions between these two systems is important, since variations in climate can trigger extensive changes in the hydrologic cycle, with significant impacts on agriculture, ecosystems, and society. Observations over the central U.S. in recent decades show numerous changes in climatic variables. This includes decreases in cloud cover and wind speed, increases in air temperature, and seasonal shifts in precipitation rate and rain/snow fraction. To assess the impacts of these variations in climate on the regional water cycle, a terrestrial ecosystem/land surface hydrologic model (Agro-IBIS) is …
Groundwater Pollution Risk Assessment Under Scenarios Of Climate And Land Use Change In The Northern Great Plains, Ruopu Li
School of Natural Resources: Dissertations, Theses, and Student Research
Modeling groundwater vulnerability to pollution is critical for implementing programs to protect groundwater quality. Traditionally, groundwater vulnerability was modeled based on current hydrogeology and land use conditions. However, groundwater vulnerability is strongly dependent on factors such as depth-to-water, recharge and land use conditions that may change in response to future changes in climate and/or socio-economic conditions. For example, global warming may lead to northward shifts in cropping patterns and changes in crop mixes (and use of farm chemicals). Meanwhile, growing demands for biofuels are resulting in expanding corn acreage, and may lead to pressures to remove land from the Conservation …
Ecological Impacts Of Stream Bank Stabilization In A Great Plains River, Christopher M. Pracheil
Ecological Impacts Of Stream Bank Stabilization In A Great Plains River, Christopher M. Pracheil
School of Natural Resources: Dissertations, Theses, and Student Research
Reduced ecological complexity, decreased water quality, and accelerated stream bank erosion are common disturbances in rivers with agriculturally dominated watersheds. Massive bank failures, increased sediment loads, and decreased riverine habitat are current problems in the agriculturally dominated Cedar River of central Nebraska. In an effort to slow erosion and prevent further ecological degradation, 20 reach scale stream bank stabilization projects were installed on the Cedar River from 2001 to 2004. The objective of this study was to determine the impact of the Cedar River stream bank stabilization projects on the ecological conditions within the Cedar River. Stream bank erosion, suspended …