Digital Commons Network^™

End-Permian (252 Mya) Deforestation, Wildfires And Flooding—An Ancient Biotic Crisis With Lessons For The Present, Vivi Vajda, Stephen Mcloughlin, Chris Mays, Tracy D. Frank, Christopher R. Fielding, Allen Tevyaw, Veiko Lehsten, Malcolm Bocking, Robert S. Nicoll

Department of Earth and Atmospheric Sciences: Faculty Publications

Current large-scale deforestation poses a threat to ecosystems globally, and imposes substantial and prolonged changes on the hydrological and carbon cycles. The tropical forests of the Amazon and Indonesia are currently undergoing deforestation with catastrophic ecological consequences but widespread deforestation events have occurred several times in Earth’s history and these provide lessons for the future. The end-Permian mass-extinction event (EPE; ∼252 Ma) provides a global, deep-time analogue for modern deforestation and diversity loss. We undertook centimeter-resolution palynological, sedimentological, carbon stable-isotope and paleobotanical investigations of strata spanning the end- Permian event at the Frazer Beach and Snapper Point localities, in the …

Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton

United States Geological Survey: Staff Publications

There is global interest in quantifying changing biodiversity in human-modified landscapes. Ecoacoustics may offer a promising pathway for supporting multi-taxa monitoring, but its scalability has been hampered by the sonic complexity of biodiverse ecosystems and the imperfect detectability of animal-generated sounds. The acoustic signature of a habitat, or soundscape, contains information about multiple taxa and may circumvent species identification, but robust statistical technology for characterizing community-level attributes is lacking. Here, we present the Acoustic Space Occupancy Model, a flexible hierarchical framework designed to account for detection artifacts from acoustic surveys in order to model biologically relevant variation in acoustic space …

Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis, Liba Pejchar

United States Geological Survey: Staff Publications

Aim: Human development and agriculture can have transformative and homogenizing effects on natural systems, shifting the composition of ecological communities towards non-native and native species that tolerate or thrive under human-dominated conditions. These impacts cannot be fully captured by summarizing species presence, as they include dramatic changes to patterns of species abundance. However, how human land use patterns and species invasions intersect to shape patterns of abundance and dominance within ecological communities is poorly understood even in well-known taxa.

Location: Conterminous United States.

Time period: 2010–2012.

Major taxa studied: Passeriformes.

Methods: We analyse continental-scale monitoring data to study the proportional …

Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, Barry R. Noon, Zachary Bowen, Brad C. Fedy

United States Geological Survey: Staff Publications

Species–environment relationships for highly mobile species outside of the breeding season are often highly dynamic in response to the collective effects of everchanging climatic conditions, food resources, and anthropogenic disturbance. Capturing dynamic space-use patterns in a model-based framework is critical as model inference often drives place-based conservation planning. We applied dynamic occupancy models to broad-scale golden eagle Aquila chrysaetos survey data collected annually from 2006 to 2012 during the late summer post-fledging period in the western US. We defined survey sites as 10 km transect segments with a 1 km buffer on either transect side (n = 3540). Derived estimates …

Human-Associated Species Dominate Passerine Communities Across The United States, Helen R. Sofaer, Curtis H. Flather, Catherine S. Jarnevich, Kristin P. Davis

United States Geological Survey: Staff Publications

Aim: Human development and agriculture can have transformative and homogenizing effects on natural systems, shifting the composition of ecological communities towards non-native and native species that tolerate or thrive under human-dominated conditions. These impacts cannot be fully captured by summarizing species presence, as they include dramatic changes to patterns of species abundance. However, how human land use patterns and species invasions intersect to shape patterns of abundance and dominance within ecological communities is poorly understood even in well-known taxa.

Location: Conterminous United States.

Time period: 2010–2012.

Major taxa studied: Passeriformes.

Methods: We analyse continental-scale monitoring data to study the proportional …

Acoustic Space Occupancy: Combining Ecoacoustics And Lidar To Model Biodiversity Variation And Detection Bias Across Heterogeneous Landscapes, Danielle I. Rappaport, J. Andrew Royle, Douglas C. Morton

United States Geological Survey: Staff Publications

There is global interest in quantifying changing biodiversity in human-modified landscapes. Ecoacoustics may offer a promising pathway for supporting multi-taxa monitoring, but its scalability has been hampered by the sonic complexity of biodiverse ecosystems and the imperfect detectability of animal-generated sounds. The acoustic signature of a habitat, or soundscape, contains information about multiple taxa and may circumvent species identification, but robust statistical technology for characterizing community-level attributes is lacking. Here, we present the Acoustic Space Occupancy Model, a flexible hierarchical framework designed to account for detection artifacts from acoustic surveys in order to model biologically relevant variation in acoustic space …

Characterization Of Pallid Sturgeon (Scaphirhynchus Albus) Spawning Habitat In The Lower Missouri River, Caroline M. Elliott, Aaron J. Delonay, Kimberly Chojnacki, Robert B. Jacobson

United States Geological Survey: Staff Publications

Acipenseriformes (sturgeons and paddlefish) globally have declined throughout their range due to river fragmentation, habitat loss, overfishing, and degradation of water quality. In North America, pallid sturgeon (Scaphirhynchus albus) populations have experienced poor to no recruitment, or substantial levels of hybridization with the closely related shovelnose sturgeon (S. platorynchus). The Lower Missouri River is the only portion of the species’ range where successful reproduction and recruitment of genetically pure pallid sturgeon have been documented. This paper documents spawning habitat and behavior on the Lower Missouri River, which comprises over 1,300 km of unfragmented river habitat. The …

Late Quaternary Sea-Level History Of Saipan, Commonwealth Of The Northern Mariana Islands, Usa: A Test Of Tectonic Uplift And Glacial Isostatic Adjustment Models, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons

United States Geological Survey: Staff Publications

In 1979, S. Uyeda and H. Kanamori proposed a tectonic model with two end members of a subduction-boundary continuum: the “Chilean” type (shallow dip of the subducting plate, great thrust events, compression, and uplift of the overriding plate) and a “Mariana” type (steep dip of the subducting plate, no great thrust events, tension, and no uplift). This concept has been used to explain variable rates of Quaternary uplift around the Pacific Rim, yet no uplift rates have been determined for the Mariana Islands themselves, one of the end members in this model. We studied the late Quaternary Tanapag Limestone, which …

Investigating Diel, Seasonal, And Interannual Variability Of Dissolved And Particulate Stable Carbon Isotope Values In A Eutrophic Boreal Lake, Rachel Henderson

Theses and Dissertations (Comprehensive)

Lakes are globally significant sources, sinks, and conduits of carbon. Cultural eutrophication of freshwater promotes the growth of phytoplankton blooms, which can transform, respire, and sequester large amounts of carbon. Analysis of stable carbon isotopes is a common tool to study the movement of carbon through the aquatic carbon cycle. The causes of temporal variability in δ¹³C values at different timescales are not well understood, and differ between lakes. In this study, I investigated diel, seasonal, and interannual variability in δ¹³C values of dissolved inorganic carbon (DIC) and particulate organic carbon (POC) in Lake 227, an …

The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys (MDVs) of Antarctica are a polar desert ecosystem consisting of alpine glaciers, ice-covered lakes, streams, and expanses of vegetation-free rocky soil. Because average summer temperatures are close to 0 Cel., the MDV ecosystem in general, and glacier melt dynamics in particular, are both closely linked to the energy balance. A slight increase in incoming radiation or change in albedo can have large effects on the timing and volume of meltwater. However, the seasonal evolution or spatial variability of albedo in the valleys has yet to fully characterized. In this study, we aim to understand the drivers …

A Basilosaurid Archaeocete (Cetacea, Pelagiceti) From The Late Eocene Of Oregon, Usa, Mark D. Uhen, David Taylor

Geology Faculty Publications and Presentations

Background: Basilosaurid archaeocetes are known from the Late Eocene of virtually all coastlines bearing coeval marine rocks except the North Pacific Basin, until now. Here we report on three consecutive posterior thoracic vertebrae of a large, basilosaurid archaeocete from a Late Eocene horizon in the Keasey Formation in Oregon.

Methods: These vertebrae were morphologically and morphometrically compared to other vertebrae of similar age from around the world.

Results: The specimens were determined to be different from all currently named species of fossil cetacean, but most similar to those found in the Gulf Coast region of North America. …

Microbial Degradability Of Terrigenous, Marsh-Exported, And Estuarine Colored Dissolved Organic Matter In Long Island Sound, John R. Supino

Dissertations and Theses

The Long Island Sound is one of the world's most urbanized estuaries, polluted from excess nutrients which impact the quality of water through increased biological productivity. Dissolved organic matter (DOM) is a sensitive indicator of anthropogenic pollution and nutrient enrichment in coastal waters as well as an important part of the carbon cycle and serves as a primary food source for aquatic food webs. Additionally, the colored portion of DOM (CDOM) impacts coastal optical properties, ocean color, and light attenuation. High levels of CDOM have been shown to inhibit the growth of phytoplankton and limit photosynthesis, damaging the food chain …

Ftir Analysis Of Bacteria Biomass-Mineral Interactions In Soils, Finola Fung-Khee

Dissertations and Theses

Soil organic carbon (SOC) accounts for 70% of the carbon on Earth. It is therefore a key player in global carbon cycling and climate change (Smith et al., 2008). Soil organic matter (SOM) is an important component of organic matter in soils (SOC), and results from biogeochemical process involving net primary producers, soil biomass and soil mineralogy (Horwath and Kuzyakov, 2018). In this study, the interplay between soil bacterial biomass and reactive clay minerals in soils was investigated. The purpose of the research was to shed light into the stabilization of SOC in a bacterial biomass-soil/clay matrix. Soils characterized as …

Burning With Potential: Understanding The Relationship Between Biochar And Agriculture Of The Northern Glaciated Plains Ecoregion, Kaitlyn Abrahamson

Electronic Theses and Dissertations

Achieving global sustainable agriculture is one of the most incredible challenges of this century, yet many continue to try to solve this problem through the development of precision technologies. Biotechnologies, such as biochar, can perform like a precision technology while protecting agricultural land from soil erosion and fertility loss. The Northern Glaciated Plains ecoregion of the United States is little researched in the benefits from the use of biochar through improved soil nutrient capture and water retention, crop health improvements, and yield increases. The study plot has four sections of corn stover biochar and eight sections of control sections. This …

Dissolved Organic Matter Movement Across Lake Superior’S Terrestrial-Stream-Coastal Interface, Karl M. Meingast

Dissertations, Master's Theses and Master's Reports

Dissolved organic matter (DOM) represents a carbon pool that can be easily translocated between ecosystems with the movement of water. This study examines the controls on DOM quantity and character delivered to Lake Superior primarily during the snowmelt period. We employed long-term stream dissolved organic carbon (DOC) data to determine quantity as well as absorption and fluorescence spectroscopy to analyze DOM structure. Our results indicate that an increasing trend in DOC concentrations, likely driven by decreases in acidity of precipitation, combined with slightly less annual runoff have resulted in relatively constant fluxes of DOM to Lake Superior. Additionally, our study …

Model-Based Estimates Of The Timing Of Brine Flux Into The Victoria Land Basin From The Mcmurdo Dry Valleys, Antarctica, Valerie Nicole Voisin

Graduate Research Theses & Dissertations

Submarine groundwater discharge (SGD) at a continental scale is one of the least constrained components of the hydrologic cycle and may represent a significant flux of iron and silica waters to the global ocean. Quantifying SGD along the Antarctic margin is complicated by complex subglacial and subsurface hydrogeology and limited observational data. Airborne transient electromagnetic (AEM) surveys have identified extensive high-salinity subsurface brines in the McMurdo Dry Valleys (MDV) that are hydrologically connected to surface features in the MDV (e.g. Taylor Glacier, saline lakes) and are potentially a significant source of SGD to McMurdo Sound. A 2D numerical model was …

Estimating Paleotemperatures In The Amundsen Sea For The Last 620,000 Years Through Diatom Morphometrics (Iodp Expedition 379), Joseph Robert Mastro

Graduate Research Theses & Dissertations

As global climate continues to rapidly change over the coming decades, West Antarctica will continue to be a significant area of concern due to its susceptibility to marine ice sheet collapse. Past collapses during Pleistocene interglacials have been hypothesized but uncertainty exists with respect to the precise timing of specific collapse events. Drill core samples collected from the Amundsen Sea continental rise during IODP Expedition 379 allow for analysis of a more continuous record of Pleistocene glacial-interglacial cycles. Here we report paleotemperature estimates from the Amundsen Sea spanning the last 620 kyr with the objective of identifying likely late Pleistocene …

Larger-Scale Ocean-Atmospheric Patterns Drive Synergistic Variability And World-Wide Volatility Of Wheat Yields, Ehsan Najafi, Indrani Pal, Reza Khanbilvardi

Advanced Science Research Center

Diagnosing potential predictability of global crop yields in the near term is of utmost importance for ensuring food supply and preventing socio-economic consequences. Previous studies suggest that a substantial proportion of global wheat yield variability depends on local climate and larger-scale ocean-atmospheric patterns. The science is however at its infancy to address whether synergistic variability and volatility (major departure from the normal) of multi-national crop yields can be potentially predicted by larger-scale climate drivers. Here, using observed data on wheat yields for 85 producing countries and climate variability from 1961–2013, we diagnose that wheat yields vary synergistically across key producing …

The Transition From Planar To En Echelon Morphology In A Single Vein In Shale: Insights From X-Ray Computed Tomography Scanning, Graham Dm Andrews, Sarah R. Brown, Johnathan Moore, Dustin Crandall, Paige Mackey

Faculty & Staff Scholarship

En echelon fractures and veins are among the most common and distinctive geological structures, yet their three-dimensional forms and relationships to surrounding structures are commonly unclear. X-ray computed tomography (CT) offers an unrivaled ability to examine structures within rocks in three dimensions, and it is applied here to a sample of drill core from the Marcellus Shale of southwestern Pennsylvania (USA). CT images yield qualitative and quantitative data on the transition from a pyrite-rich planar vein to an en echelon veinlet array, and on the heterogeneity of veinlets within the array. Using a combination of three- and two-dimensional images, geometric …

Water Sourcing Strategies Of Highly Resilient Vegetation In Desert Soils: Stable Isotope Analysis Of A Northern Chihuahuan Desert Ecosystem, Hayden Eleanor Thompson

Open Access Theses & Dissertations

Plant water use strategies and water transport dynamics are important for understanding ecosystem productivity and soil-vegetation-atmosphere interactions within an environment (Li et al., 2007). Recent research using stable isotope analysis in wet and humid climates has found that vegetation uses tightly particle-bound water stored in the soil that does not participate in translatory flow (Brooks et al., 2010; Goldsmith et al., 2011; McDonnell 2014). In arid and semi-arid deserts of the United States, highly resilient vegetation, such as the Honey Mesquite (Prosopis glandulosa) and the Creosote shrub (Larrea tridentata), exhibit some degree of activity year-round despite limited water availability during …

Lévy Processes: Characterizing Volcanic And Financial Time Series, Peter Kwadwo Asante

Open Access Theses & Dissertations

In this work, we use the Diffusion Entropy Analysis (DEA) to analyze and detect the scaling properties of time series from both emerging and well established markets as well as volcanic eruptions recorded by a seismic station, both financial and volcanic time series data are known to have high frequencies (i.e they are collected at an extremely fine scale). The objective is to determine the characterization i.e whether they follow a Gaussian or Lévy distribution. If they do follow a Lévy distribution we are then interested in finding if they are characterized by a Lévy walk which has a finite …

Paleoecology Of Bivalves In The Carmel Formation (Middle Jurassic, Bajocian) Of Utah, Evan L. Shadbolt

Senior Independent Study Theses

The Carmel Formation of the Middle Jurassic has many mysteries. One of these enigmas is its bivalves. The formation contains the famous oyster balls called ostreoliths. Despite bivalves making up 80 percent of the fossils found in the Carmel Formation, it is not understood how the bivalves lived in this community. The formation is located in southwestern and central Utah. It was deposited when an epicontinental seaway covered most of Utah. The paleoclimate of Utah was hot and dry, which meant that the environment was evaporite heavy. This also meant that the seawater at the southernmost extent of the seaway …

Agricultural And Environmental Weeds Of South Texas And Their Management, Pushpa Soti, John A. Goolsby, Alexis Racelis

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The Lower Rio Grande Valley (LRGV) in south Texas is one of the most productive agricultural regions in southern United States. With subtropical climate and highly fertile soils, this region provides a year-round growing condition for crops. Along with citrus, major crops grown in the region are sorghum cotton and corn in the summer and vegetables in winter. Thus, a fallow period of 3-6 months between successive crops is common in the region. Growers in this region report weeds as their number one economic and agronomic problem affecting crop yield and quality and increasing the cost of production and weeds …

Hydromorphological Changes Of Chi River, Mueang District, Khon Kaen Province, Pawat Wattanachareekul

Chulalongkorn University Theses and Dissertations (Chula ETD)

This thesis focuses on the analysis of hydrology coupled with geomorphology for river management such as flood mitigation and river restoration. Morphological Quality Index (MQI) is used for assessing hydro-morphological conditions from part of the Chi River (67 km long) at Khon Kaen province, a major river in north-eastern Thailand. This study area has been suffering from unexpected and repeated flooding. MQI is applied to evaluate the degree of hydro-morphological alteration in terms of relative scores (from 0 to 1). Basically, in case that MQI score equals 1, it means the area has no any alteration. On the other hand, …

ผลของโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ต่อสมรรถนะ ของทหารกองประจำการ: กรณีศึกษา มณฑลทหารบกที่ 21 จังหวัดนครราชสีมา, วีรยุทธ หมื่นบุญมี

Chulalongkorn University Theses and Dissertations (Chula ETD)

การวิจัยครั้งนี้เป็นงานวิจัยแบบกึ่งทดลอง (Quasi-experimental research design) แบบกลุ่มเดียววัดก่อนและหลังการทดลอง (One-group Pretest-posttest Design) เพื่อศึกษาสมรรถนะของทหารกองประจำการหลังการได้รับโปรแกรมการเรียนรู้แบบบูรณาการ ในการจัดการภัยพิบัติและอุบัติภัยหมู่และเพื่อเปรียบเทียบสมรรถนะของทหารกองประจำการก่อนและหลังได้รับโปรแกรมการเรียนรู้ แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ กลุ่มตัวอย่างในการวิจัยครั้งนี้ คือ ทหารกองประจำการ มณฑลทหารบกที่ 21 จังหวัดนครราชสีมา จำนวน 40 คน คัดเลือกแบบเฉพาะเจาะจง (Purposive Sampling) เข้าร่วมโปรแกรมการเรียนรู้แบบบูรณาการ ในการจัดการภัยพิบัติและอุบัติภัยหมู่ เครื่องมือในการวิจัยประกอบด้วย 1) เครื่องมือที่ใช้ในการรวบรวมข้อมูล ได้แก่ แบบสอบถามข้อมูล ส่วนบุคคล 2) เครื่องมือที่ใช้ในการดำเนินการทดลอง ได้แก่ 2.1) แบบประเมินสมรรถนะของทหารกองประจำการ มีค่าความเที่ยง เท่ากับ .77 และ 2.2) โปรแกรมการเรียนรู้แบบบูรณาการในจัดการภัยพิบัติและอุบัติภัยหมู่ต่อสมรรถนะของทหารกองประจำการ และ 3) เครื่องมือกำกับการทดลอง ได้แก่ แบบทดสอบความรู้ก่อนเรียนและหลังเรียน (Pre-test and Post-test) มีค่าความเที่ยง เท่ากับ .91 วิเคราะห์ข้อมูลโดยใช้ร้อยละ ค่าเฉลี่ย ส่วนเบี่ยงเบนมาตรฐาน และการทดสอบค่าที ผลการวิจัยสรุปว่า 1. สมรรถนะของทหารกองประจำการหลังการได้รับโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ มีค่าเฉลี่ยคะแนนสูงกว่าก่อนได้รับโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ อย่างมีนัยสำคัญทางสถิติที่ระดับ .05 พบว่า คะแนนสมรรถนะของทหารกองประจำการหลังเข้าร่วมโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ อยู่ในระดับสูง 2. สมรรถนะของทหารกองประจำการก่อนได้รับโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ มีค่าคะแนนเฉลี่ย 25.15 ซึ่งพบว่าอยู่ในระดับต่ำ และหลังได้รับโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ มีค่าคะแนนเฉลี่ย 45.08 ซึ่งพบว่าอยู่ในระดับสูง เมื่อพิจารณาเปรียบเทียบค่าคะแนนเฉลี่ยสมรรถนะของทหารกองประจำการหลังได้รับโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่สูงกว่าก่อนได้รับโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการ ภัยพิบัติและอุบัติภัยหมู่ อย่างมีนัยสำคัญทางสถิติที่ระดับ .05 แสดงให้เห็นว่าโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่ตอบสนองต่อสมรรถนะ ของทหารกองประจำการได้มากขึ้น จึงส่งผลให้ค่าคะแนนเฉลี่ยสมรรถนะของทหารกองประจำการสูงขึ้นหลังจากเข้าร่วมโปรแกรมการเรียนรู้แบบบูรณาการในการจัดการภัยพิบัติและอุบัติภัยหมู่

The Prebiotic Provenance Of Semi-Aqueous Solvents, Jennifer L. Lago, Bradley T. Burcar, Nicholas V. Hud, Rio Febrian, Christopher A. Mehta, Paul J. Bracher, Zachary D. Atlas, Matthew A. Pasek

School of Geosciences Faculty and Staff Publications

The numerous and varied roles of phosphorylated organic molecules in biochemistry suggest they may have been important to the origin of life. The prominence of phosphorylated molecules presents a conundrum given that phosphorylation is a thermodynamically unfavorable, endergonic process in water, and most natural sources of phosphate are poorly soluble. We recently demonstrated that a semi-aqueous solvent consisting of urea, ammonium formate, and water (UAFW) supports the dissolution of phosphate and the phosphorylation of nucleosides. However, the prebiotic feasibility and robustness of the UAFW system are unclear. Here, we study the UAFW system as a medium in which phosphate minerals …

Utilizing Ecological Niche Modelling To Predict Habitat Suitability Of Eastern Equine Encephalitis In Florida, Claire Burch, Rebecca Loraamm, Thomas R. Unnasch, Joni A. Downs

School of Geosciences Faculty and Staff Publications

Eastern Equine Encephalitis virus (EEEV) is a virus found predominantly east of the Mississippi River in the United States that can be fatal to both equines and humans. The disease has previously been most prolific in states like Florida, but there has been an increase in the prevalence in other states further up north on the east coast of the United States in recent years. The purpose of this research is to use the ecological niche modelling program Maxent to model EEEV habitat suitability probability. This research utilized data of fatality incidence in equine hosts, versus sentinel chicken infection data, …

Optimizing Arbovirus Surveillance Using Risk Mapping And Coverage Modelling, Joni A. Downs, Mehrdad Vaziri, George Deskins, William Kellner, Kristi M. Miley, Thomas R. Unnasch

School of Geosciences Faculty and Staff Publications

Diseases carried by mosquitoes and other arthropods endanger human health globally. Though costly, surveillance efforts are vital for disease control and prevention This paper describes an approach for strategically configuring targeted disease surveillance sites across a study area. The methodology combines risk index mapping and spatial optimization modelling. The risk index is used to identify demand for surveillance, and the maximum covering location problem is used to select a specified number of candidate surveillance sites that covers the maximum amount of risk. The approach is demonstrated using a case study where optimal locations for sentinel surveillance sites are selected for …

A Hydrologic Landscapes Perspective On Groundwater Connectivity Of Depressional Wetlands, Brian P. Neff, Donald O. Rosenberry, Scott G. Leibowitz, Dave M. Mushet, Heather E. Golden, Mark C. Rains, J. R. Brooks, Charles R. Lane

School of Geosciences Faculty and Staff Publications

Research into processes governing the hydrologic connectivity of depressional wetlands has advanced rapidly in recent years. Nevertheless, a need persists for broadly applicable, non-site-specific guidance to facilitate further research. Here, we explicitly use the hydrologic landscapes theoretical framework to develop broadly applicable conceptual knowledge of depressional-wetland hydrologic connectivity. We used a numerical model to simulate the groundwater flow through five generic hydrologic landscapes. Next, we inserted depressional wetlands into the generic landscapes and repeated the modeling exercise. The results strongly characterize groundwater connectivity from uplands to lowlands as being predominantly indirect. Groundwater flowed from uplands and most of it was …

Paleoecological Successions From Shallow-Marine Depositional Environments In Upper Silurian Carbonate Rocks Of Blair County, Pennsylvania, Shadya El-Ashkar

Graduate Theses, Dissertations, and Problem Reports (ETD)

Studies of paleoenvironment and paleoecology are important for investigating relationships between the different environmental and biological variables that influenced biodiversification patterns during the Silurian Period. The mixed carbonate and siliciclastic rocks of the Bloomsburg and Mifflintown Formations in central Pennsylvania represent transitions between carbonate ramp and deltaic settings. The goal of this study was to assess changes in depositional environment and paleoecology of an undescribed Bloomsburg/Mifflintown locality in Bellwood, Pennsylvania. In central Pennsylvania, the interfingered relationship of mixed carbonate and siliciclastic mudstones of the Mifflintown Formation with red fine-grained sandstones and shales of the Bloomsburg Formation presented challenges for deciphering …