Digital Commons Network^™

Penetration Of Uv-Visible Solar Radiation In The Global Oceans: Insights From Ocean Color Remote Sensing, Zhongping Lee, Chuanmin Hu, Shaoling Shang, Keping Du, Marlon Lewis, Robert Arnone, Robert Brewin

Marine Science Faculty Publications

Penetration of solar radiation in the ocean is determined by the attenuation coefficient (K_d(λ)). Following radiative transfer theory, K_d is a function of angular distribution of incident light and water's absorption and backscattering coefficients. Because these optical products are now generated routinely from satellite measurements, it is logical to evolve the empirical K_d to a semianalytical K_d that is not only spectrally flexible, but also the sun-angle effect is accounted for explicitly. Here, the semianalytical model developed in Lee et al. (2005b) is revised to account for the shift of phase …

Geo402/585: Field Methods; Labs 4-5 Gordon Natural Area Carbon Stock Pilot Study, Joy Fritschle

Gordon Natural Area-related Curricula Documents

No abstract provided.

The Contested Vision For Agriculture's Future: Sustainable Intensive Agriculture And Agroecology, Drew L. Kershen

Faculty Articles

No abstract provided.

Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer

Electronic Theses and Dissertations

Sagebrush (Artemisia spp.) ecosystems constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. Disturbances continue to alter this ecosystem, with climate change possibly representing the greatest future disturbance risk. Improved ways to characterize and monitor gradual change in this ecosystem are vital to its future management. A new remote sensing sagebrush characterization approach was developed in Wyoming which integrates three scales of remote sensing to derive four primary continuous field components (bare ground, herbaceousness, litter, and shrub), and four secondary components (sagebrush, big sagebrush, Wyoming sagebrush, and shrub …

Ecology Of Glacial Relict Fishes In South Dakota's Sandhills Region, Eli Felts

Electronic Theses and Dissertations

Native stream fish zoogeography has changed substantially across North America during the last century as habitat degradation, stream fragmentation and introductions of nonnative species have led to numerous extinctions, extirpations and altered distributions. Insufficient information regarding imperiled species often results in reactive, rather than proactive, management, and knowledge of species status and ecology is critical in identifying conservation priorities. South Dakota populations of three dace species (northern redbelly dace Chrosomus eos, finescale dace Chrosomus neogaeus, and pearl dace Margariscus margarita) are relict of Pleistocene Glaciation and are isolated from the northern core of their distribution, but little information exists regarding …

Energy In The Corn Belt: Is Maize Production Sustainable?, Matthew Bernau

Electronic Theses and Dissertations

Technological and scientific innovation has transformed agricultural production. Corn production methods changed from a sustainable, nutrient recycling production system to one reliant on imported fossil energy inputs. Located in the Western Corn Belt, Union County, South Dakota was chosen as the study area. Changes in production methods are represented by four technological epochs: 1) The Draft Horse Epoch, 1890-1920; 2) The Tractor Epoch, 1920-1950; 3) The Fertilizer Epoch, 1950-1980; and 4) The Biotechnology and Precision Agriculture Epoch, 1980-2010. The energy budget method was used to measure the energy sustainability of corn production. The findings show that the volume of corn …

Threshold Responses Of Forest Birds To Landscape Changes Around Exurban Development, Todd R. Lookingbill, Marcela Suarez-Rubio, Scott Wilson, Peter Leimgruber

Geography and the Environment Faculty Publications

Low-density residential development (i.e., exurban development) is often embedded within a matrix of protected areas and natural amenities, raising concern about its ecological consequences. Forest-dependent species are particularly susceptible to human settlement even at low housing densities typical of exurban areas. However, few studies have examined the response of forest birds to this increasingly common form of land conversion. The aim of this study was to assess whether, how, and at what scale forest birds respond to changes in habitat due to exurban growth. We evaluated changes in habitat composition (amount) and configuration (arrangement) for forest and forest-edge species around …

Impacts Of Insecticide Treatments On Platytetranychus Multidigituli (Acari:Tetranychidae) And Predatory Mites On Gleditsia Triacanthos Var. Inermis (Honeylocust), Adam Robert Witte

Open Access Theses

Spider mite outbreaks can occur in urban forests after insecticides are applied to control early season pests. We used thornless honeylocust (Gleditsia triacanthos var. inermis) and honeylocust spider mite (Platytetranychus multidigituli) as a model to investigate this phenomenon by applying both topical and systemic insecticides to treat early season pests of honeylocust. Impacts of these applications on populations of P. multidigituli and its associated predatory mites were assessed. Early season applications of bifenthrin caused outbreaks of honeylocust spider mite and drastically reduced phytoseiids but not the stigmaeid mite, Zetzellia mali. In contrast later season applications suppressed populations of P. multidigituli. …

Sensitivity Of Grassland Plant Community Composition To Spatial Vs. Temporal Variation In Precipitation, Elsa E. Cleland, Scott L. Collins, Timothy L. Dickson, Emily C. Farrer, Katherine L. Gross, Laureano A. Gherardi, Lauren M. Hallett, Richard J. Hobbs, Joanna S. Hsu, Laura Turnball, Katharine N. Suding

Biology Faculty Publications

Climate gradients shape spatial variation in the richness and composition of plant communities. Given future predicted changes in climate means and variability, and likely regional variation in the magnitudes of these changes, it is important to determine how temporal variation in climate influences temporal variation in plant community structure. Here, we evaluated how species richness, turnover, and composition of grassland plant communities responded to interannual variation in precipitation by synthesizing long-term data from grasslands across the United States. We found that mean annual precipitation (MAP) was apositive predictor of species richness across sites, but a positive temporal relationship between annual …

Program And Proceedings: Nebraska Academy Of Sciences 1880–2013, 133rd Anniversary Year, One Hundred-Twenty-Third Annual Meeting

Nebraska Academy of Sciences: Programs and Proceedings

Aeronautics and Space Science

Collegiate Academy: Biology

Biological and Medical Sciences

Nebraska Chapter, National Council for Geographic Education

Chemistry and Physics

Collegiate Academy: Chemistry and Physics

Junior Academy, Senior High Competition

Aeronautics and Space Science, Poster Session

Anthropology

Nebraska Wesleyan University Health and Sciences Graduate School Fair

Aeronautics and Space Science, Poster Session

Maiben Memorial Lecture: Making People Smarter Using "Habits of Mind," Bob Feurer, North Bend High School

Collegiate Academy: Biology

Teaching of Science and Math

Applied Science and Technology

Junior Academy, Junior High Competition

Population Genetics And Ecology Of Regional Malaria Vectors In Amazonian Brazil, Sascha Naomi Mckeon

Legacy Theses & Dissertations (2009 - 2024)

Species complexes are common among anopheline mosquitoes, but only some members of complexes are disease vectors. Research involving overall patterns of divergence, phylogenetic relationships and population structure is partly driven by the operational need to be able to reliably distinguish component taxa that may be involved in malaria transmission. Anopheles triannulatus, An. nuneztovari and An. albitarsis are broadly distributed species complexes that contain local and regionally important malaria vectors, whose genetic diversity has been largely overshadowed by studies involving An. darlingi, the principal vector of Central and South America. I have analyzed the ecological suitability of habitats and geographical ranges …

Floristic Diversity And Vegetation Analysis Of Wadi Al-Noman, Mecca, Saudi Arabia, Kadry Abdel Khalik, Mohamed El-Sheikh, Abeer El-Aidarous

Turkish Journal of Botany

Wadi Al-Noman in Mecca is one of the most important wadis. It was included among the most important water sources where the springs and wells of Zobida run and it provides drinking water for the holy places in Mecca and visitors to the Kaaba and Arafat regions. The present study provides an analysis of floristic composition, vegetation types, and structure and species distribution at 20 sites, emphasising the environmental factors that affect species distribution. A total of 126 species representing 39 families of vascular plants are recorded. Fabaceae, Poaceae, and Boraginaceae are the largest families, and therophytes and chamaephytes are …

Contributions To Lichen Diversity Of Turkey From The Sarısu Area (Kocaeli), Gülşah Çobanoğlu, Bi̇rkan Açikgöz, Laurentiu Baloniu

Turkish Journal of Botany

A total of 85 lichen taxa from the Sarısu area of the district of Kandıra in Kocaeli Province were listed. Three new records for the biota of Turkey, Coenogonium pineti (Ach.) Lücking & Lumbsch, Lecania cuprea (A.Massal.) Van den Boom & Coppins, and Opegrapha calcarea Turner ex Sm., have been identified within the context of this study along with 81 new taxa for the province of Kocaeli.

The Effect Of Visual Wulst Lesions And Trigeminal Nerve Sectioning On The Discrimination Of Magnetic Inclination In The Homing Pigeon (Columba Livia), Merissa Acerbi

Honors Projects

The ability of homing pigeons to return to their loft from unknown places has fascinated scientists for centuries. It is well established that homing pigeons, like migratory birds, posses an innate magnetic inclination compass to determine direction by measuring the angle between the magnetic field vector and the Earth's surface. Recent work has indicated that the avian magnetic compass is light mediated and appears to mediate magnetic information to the brain. This occurs via a visual pathway with processing in the visual Wulst area of the forebrain. There is, however, also evidence from other avian species that magnetic direction may …

Phylogeography Of Notropis Nubilus (Ozark Minnow), Jason F. Dugan

Dissertations and Theses @ UNI

Periodic glacial cycles beginning 2.6 million years ago to 10,000 years ago forced the repeated contraction, fragmentation, and expansion of the North American biota. In the upper Mississippi River basin three very different areas characterize the topography left by glaciations and still and influence the flora and fauna: Driftless Area, Paleozoic Plateau, and Iowan Surface. The Paleozoic Plateau is located in the northern part of the upper Mississippi River basin, and it is a unique geographical region situated in an area that straddles northeast Iowa, southeastern Minnesota, southwest Wisconsin, and northwest Illinois. This region was bypassed by the last glacial …

Plant Community Composition And Structure Monitoring For Agate Fossil Beds National Monument, 2012 Annual Report, Isabel W. Ashton, Stephen K. Wilson, Daniel J. Swanson, Michael Prowatzke, Phil Graeve

United States National Park Service: Publications

Executive Summary

Agate Fossil Beds National Monument (AGFO) plays a vital role in protecting and managing some of the last remnants of native mixed-grass prairie in the region. The Northern Great Plains Inventory & Monitoring Network (NGPN) and Fire Ecology Program (FireEP) surveyed 12 long-term monitoring plots in Agate Fossil Beds National Monument in 2012 as part of an effort to better understand the condition of plant communities in the park. We measured plant diversity and cover, looked for the presence of exotic species that may be newly invading the park, and evaluated the amount of human and natural disturbance …

Survival And Behavior Of Chinese Mystery Snails (Bellamya Chinensis) In Response To Simulated Water Body Drawdowns And Extended Air Exposure, Kody M. Unstad, Daniel R. Uden, Craig R. Allen, Noelle M. Chaine, Danielle M. Haak, Robert A. Kill, Kevin L. Pope, Bruce J. Stephen, Alec Wong

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Nonnative invasive mollusks degrade aquatic ecosystems and induce economic losses worldwide. Extended air exposure through water body drawdown is one management action used for control. In North America, the Chinese mystery snail (Bellamya chinensis) is an invasive aquatic snail with an expanding range, but eradication methods for this species are not well documented. We assessed the ability of B. chinensis to survive different durations of air exposure, and observed behavioral responses prior to, during, and following desiccation events. Individual B. chinensis specimens survived air exposure in a laboratory setting for > 9 weeks, and survivorship was greater among adults …

Estimation Of Aerosolized Antibiotic Resistant Bacteria Concentrations From Wastewater Treatment Facilities Using Spatially-Based Dispersion Modeling, Renee Nichole Dickman

Theses and Dissertations

Pathogenic bacteria can develop resistance to antibiotics to which they were previously sensitive, resulting in increased morbidity and mortality worldwide [1]. The increase in drug resistance in bacteria is an emerging public health concern. The activated sludge tanks of wastewater treatment plants are known sources of antibiotic resistant bacteria. These resistant bacteria can become aerosolized and disperse downwind. Using previously sampled aerosol concentrations and meteorological data, a Gaussian dispersion model was developed to estimate the concentration downwind from a selected wastewater treatment facility. The emission rate was calculated to be 7,941 CFU/m²/sec ± 2,149 CFU/m²/sec. This value was used in …

Evaluating Habitat Vulnerability And Sustainability Of Urban Seagrass Resources To Sea Level Rise, Cynthia A. Meyer

USF Tampa Graduate Theses and Dissertations

The seagrass resource provides essential ecosystem functions for many marine species. This research evaluated the vulnerability and sustainability of the seagrass resource in an urbanized area to the effects of sea level rise. The assessment required analysis of information regarding the biogeography of the seagrass resource, and developing a method to model the spatial extent of the suitable habitat for seagrass, and applying the model to predict the implications of simulated sea level rise scenarios on the seagrass resource.

Examining the biogeography of the seagrass resource required the development of a seagrass monitoring and assessment field survey and a comprehensive …

Floracultures: Conserving Perth's Botanical Heritage Through A Digital Repository, John C. Ryan

Research outputs 2013

FloraCultures is a 2013 pilot project in development with Kings Park and Botanic Garden in Perth, Western Australia, and funded by Edith Cowan University’s Early Career Researcher grant scheme. The project aims to develop a model for documenting the plant-based cultural heritage of 30–50 indigenous species occurring in the Kings Park bushland. The FloraCultures initiative integrates archival and digital design techniques, creating a unique web portal of potential interest to a range of users -- from first-time tourists and amateur naturalists to heritage consultants and evironmental conservationists . The initiative reflects the belief that research into environmental heritage (defined broadly …

Utilisation Of Spent Dairy Yeast Kluyveromyces Marxianus For The Production Of Flavoured Yeast Extracts., Brendan Mccarra

Theses

Spent dairy yeast Kluyveromyces marxianus (SDYK), a by-product of whey to ethanol fermentations, was investigated as a natural biomass source for the production of alternative flavoured yeast extracts. SDYK which was characterised by a high protein content (55.3% (w/w) ± 0.8) and comparable levels of flavor enhancing amino acids to that of S. cerevisiae was prepared for induced autolysis at different pH values in the presence of inductors sodium chloride and the proteolytic enzyme papain. An induced autolysis process was developed for the production of flavoured yeast extracts in which pH and autolytic treatment applied were found to have a …

Phylogeography Of The Malagasy Ant Species Otontomachus Coquereli, Jason Jackson

Electronic Theses and Dissertations

Madagascar is an extremely diverse and geographically complex area boasting levels of endemism that blatantly raise questions about their origins. There is evidence that these endemics arose via insitu diversification during Madagascar's ~88 million year isolation, even though it was essentially in the middle of Gondwana with ample opportunity to acquire inhabitants. Madagascar's high levels of diversity and endemism make it an ideal location to study speciation, especially considering the evidence that such high levels speciation occurred in Madagascar itself. Several hypotheses have been formulated to relate the complex geography to genetic divergence, and thereby speciation. I explore three hypotheses …

The Relative Contribution Of Methanotrophs To Microbial Communities And Carbon Cycling In Soil Overlying A Coal-Bed Methane Seep, Christopher T. Mills, Gregpry F. Slater, Robert F. Dias, Stephanie A. Carr, Christopher M. Reddy, Raleigh Schmidt, Kevin W. Mandernack

Chemistry & Biochemistry Faculty Publications

Seepage of coal-bed methane (CBM) through soils is a potential source of atmospheric CH₄ and also a likely source of ancient (i.e. ¹⁴C-dead) carbon to soil microbial communities. Natural abundance ¹³C and ¹⁴C compositions of bacterial membrane phospholipid fatty acids (PLFAs) and soil gas CO₂ and CH₄ were used to assess the incorporation of CBM-derived carbon into methanotrophs and other members of the soil microbial community. Concentrations of type I and type II methanotroph PLFA biomarkers (16:1ω8c and 18:1ω8c, respectively) were elevated in CBM-impacted soils compared with a control site. Comparison …

Weed Flora In The Reclaimed Lands Along The Northern Sector Of The Nile Valley In Egypt, Monier Abd El-Ghani, Ashraf Soliman, Rim Hamdy, Ebtesam Bennoba

Turkish Journal of Botany

Deserts comprise about 95% of the total land surface of Egypt; therefore, their potential for production must be assessed. Weed communities are mainly affected by the environment, and studies may increase our knowledge of the relationship among the weed flora, soil properties, crop rotation, soil management, fertiliser usage, and weed control. The area under study is one of the most recently reclaimed lands. The recorded 150 species in the monitored 19 sites were distributed within 33 families. The species-rich families were: Poaceae (31), Asteraceae (23), Brassicaceae (13), Chenopodiaceae (12), and Fabaceae (12). Chorological analysis revealed that the widely distributed species …

Vegetation And Soil Relationships In The Inland Wadi Ecosystem Of Central Eastern Desert, Egypt, Fawzy Salama, Monier Abd El-Ghani, Noha El-Tayeh

Turkish Journal of Botany

In January 2010, torrential rains that had suddenly swept away a limited area in the Eastern Desert facing Qena Province in Upper Egypt resulted in the enriching of the vegetation of some extremely dry wadis at this location. A vegetation survey carried out shortly after this event, in April, revealed the prevalence of annuals in considerable abundance, which are hardly recognisable in such usually dry habitats. The normally scarce perennial vegetation had flourished, too. A total of 32 species, 11 annuals, and 21 perennials that belong to 27 genera and 15 families were recorded. The life-form spectrum in the present …

Agroforestry And Smallholder Farmers: Climate Change Adaptation Through Sustainable Land Use, Colin Mccabe

Capstone Collection

Agriculture in the developing world will be extremely hard hit by climate change, and smallholder farmers in Least Developed Countries (LDCs) are among the most vulnerable to its impacts. There is a range of agricultural adaptations to climate change, and each context demands a unique appraisal of impacts and adaptations based on specific geography, local climate variability and expected change, and social conditions. The term “climate-smart agriculture” (CSA) has come to embody a set of practices in crop and livestock cultivation that 1) reduce greenhouse gas emissions (climate change mitigation), 2) build resilience to the impacts of climate change for …

Population Genetics Of Thomomydoecus Minor: Ectoparasitic Chewing Lice On Thomomys Bottae Pocket Gophers Of The Rio Grande Valley In New Mexico, Sheree Elizabeth Harper

Dissertations and Theses @ UNI

Thomomydoecus minor is an ectoparasitic chewing louse that lives in intimate association with the pocket gopher Thomomys bottae. Chewing lice are wingless, obligate, host specific parasites that spend their entire life cycle on the fur of their host. Pocket gophers are fossorial and asocial, cut off for most of their lives even from members of their own species. Thus, the life histories of both chewing lice and pocket gophers have been predicted to limit transmission of lice from host to host, thus limiting gene flow among louse infrapopulations found on different hosts and increasing the effect of louse population …

Continental-Scale Assessment Of Genetic Diversity And Population Structure In Quaking Aspen (Populus Tremuloides), Colin M. Callahan, Carol A. Rowe, Ronald J. Ryel, John D. Shaw, Michael D. Madritch, Karen E. Mock

Wildland Resources Faculty Publications

Aim: Quaking aspen (Populus tremuloides) has the largest natural distribution of any tree native to North America. The primary objectives of this study were to characterize range-wide genetic diversity and genetic structuring in quaking aspen, and to assess the influence of glacial history and rear-edge dynamics.

Location: North America.

Methods: Using a sample set representing the full longitudinal and latitudinal extent of the species’ distribution, we examined geographical patterns of genetic diversity and structuring using 8 nuclear microsatellite loci in 794 individuals from 30 sampling sites.

Results: Two major genetic clusters were identified across the range: a southwestern cluster and …

Molecular Phylogeny Of Galanthus (Amaryllidaceae) Of Anatolia Inferred From Multiple Nuclear And Chloroplast Dna Regions, Ni̇vart Taşci Margoz, İbrahi̇m Sirri Yüzbaşioğlu, Zeynep Çelen, Tuna Eki̇m, Ayşe Neşe Bi̇lgi̇n

Turkish Journal of Botany

Anatolia hosts 14 of the 22 taxa of genus Galanthus L. The phylogenetic relationships of Galanthus species were explored using DNA sequence data from both nuclear and chloroplast DNA of 70 specimens covering all subdivisions of Galanthus present in Turkey. Our data showed that species of the same geography clustered together phylogenetically, in contrast to the presently recognized taxonomy based on morphological characters. The 5.8S rRNA sequence data by itself is sufficiently informative for constructing phylogenetic trees. Our data confirm the identity of Galanthus koenenianus as a new taxon, well separated from G. alpinus; both are clustered within subseries Viridifolii, …

The Elwha River Restoration: Landscape Change, Salmon, And Sense Of Place, Kelseyanne Johnson

All Master's Theses

Removal of the Elwha River dams to restore the ecosystem and salmon fisheries is the largest project of its kind in the history of the United States. Spanning decades and affecting generations, this project has changed and will continue to change the landscape. This research examined the influence of the anticipated return of salmon on 18 key stakeholders' sense of place of the Elwha River. For almost all stakeholders, changes to the Elwha landscape are welcomed as they expect that salmon will restore the ecosystem to its natural state. Narrative data revealed dominant themes in participants' sense of place expressed …