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Critical Analysis Of The Value Of Drought Information And Impacts On Land Management And Public Health, Tingting Liu, Kelly Helm Smith, Richard Krop, Tonya Haigh, Mark Svoboda Jan 2020

Critical Analysis Of The Value Of Drought Information And Impacts On Land Management And Public Health, Tingting Liu, Kelly Helm Smith, Richard Krop, Tonya Haigh, Mark Svoboda

National Drought Mitigation Center: Faculty Publications

This paper reviews previous efforts to assign monetary value to climatic or meteorological information, such as public information on drought, climate, early warning systems, and weather forecast information. Methods and tools that have been explored to examine the benefits of climatic and meteorological information include the avoided cost, contingent valuation, choice experiments, benefit transfer, and descriptive approaches using surveys. The second part of this paper discusses specific considerations related to valuing drought information for public health and the Bureau of Land Management. We found a multitude of connections between drought and the land management and health sectors in the literature. …


Using Climate To Explain And Predict West Nile Virus Risk In Nebraska, Kelly Smith, Andrew Tyre, Jeff Hamik, Michael Hayes, Yuzhen Zhou, Li Dai Jan 2020

Using Climate To Explain And Predict West Nile Virus Risk In Nebraska, Kelly Smith, Andrew Tyre, Jeff Hamik, Michael Hayes, Yuzhen Zhou, Li Dai

National Drought Mitigation Center: Faculty Publications

We used monthly precipitation and temperature data to give early warning of years with higher West Nile Virus (WNV) risk in Nebraska. We used generalized additive models with a negative binomial distribution and smoothing curves to identify combinations of extremes and timing that had the most influence, experimenting with all combinations of temperature and drought data, lagged by 12, 18, 24, 30, and 36 months. We fit models on data from 2002 through 2011, used Akaike's Information Criterion (AIC) to select the best‐fitting model, and used 2012 as out‐of‐sample data for prediction, and repeated this process for each successive year, …


The Importance Of Understanding Trophic Transfer In Top Marine Predators Due To An Increase In Plastic Production, Annika M. Markovich Jan 2020

The Importance Of Understanding Trophic Transfer In Top Marine Predators Due To An Increase In Plastic Production, Annika M. Markovich

Scientific Communication News

No abstract provided.


Thirty Years Of Data Sheds Light On Plastic Pollution In The Deep Sea, Adam Warren Jan 2020

Thirty Years Of Data Sheds Light On Plastic Pollution In The Deep Sea, Adam Warren

Scientific Communication News

No abstract provided.


Dolphin Study Gives Insight Into Marine Mammal Threat Response, Marshall Hawkins Jan 2020

Dolphin Study Gives Insight Into Marine Mammal Threat Response, Marshall Hawkins

Scientific Communication News

No abstract provided.


Using Ground Penetrating Radar To Investigate A Sedimentary Archive At Pj Hoffmaster State Park, Peter Duimstra, Melinda C. Higley Jan 2020

Using Ground Penetrating Radar To Investigate A Sedimentary Archive At Pj Hoffmaster State Park, Peter Duimstra, Melinda C. Higley

Summer Research

Ground Penetrating Radar is a non-invasive method of observing the Earth’s subsurface using emitted radio waves. The coastal dune environment present at PJ Hoffmaster State Park represents an ideal environment to utilize this technology (1). The contrast of subsurface soils show up as reflective layers which can be interpreted as sedimentary layers using GPR data. Subsurface layers provide insight to the historic dune structure, revealing past erosional or depositional events and possibly paleo wind directions (2).


Revision Of The Genus Styxosaurus And Relationships Of The Late Cretaceous Elasmosaurids (Sauropterygia: Plesiosauria) Of The Western Interior Seaway, Elliott Armour Smith Jan 2020

Revision Of The Genus Styxosaurus And Relationships Of The Late Cretaceous Elasmosaurids (Sauropterygia: Plesiosauria) Of The Western Interior Seaway, Elliott Armour Smith

Theses, Dissertations and Capstones

Growing evidence indicates that elasmosaurid plesiosaurs from the Late Cretaceous Western Interior Seaway are members of a single clade, the Styxosaurinae. The styxosaurines are reported to be mostly Campanian in age, and taxa within the clade obtain the longest necks, by number of cervical vertebrae, of any known vertebrate. The styxosaurines are morphologically diverse and include taxa that exhibit a secondary reduction in neck length. Given the evolutionary plasticity of postcranial characters in plesiosaurs in general, and neck length in elasmosaurs, scrutiny of cranial osteology is pertinent to advancing understanding of Western Interior Seaway elasmosaurids. This study finds that an …


Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila Jan 2020

Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila

United States Geological Survey: Staff Publications

Pesticides coated to the seed surface potentially pose an ecological risk to granivorous birds that consume incompletely buried or spilled seeds. To assess the toxicokinetics of seeds treated with current-use fungicides, Japanese quail ( Coturnix japonica) were orally dosed with commercially coated wheat seeds. Quail were exposed to metalaxyl, tebuconazole, and fludioxonil at either a low dose (0.0655, 0.0308, and 0.0328 mg/kg of body weight, respectively) or a high dose (0.196, 0.0925, and 0.0985 mg/kg of body weight, respectively). Fungicides were rapidly absorbed and distributed to tissues. Tebuconazole was metabolized into tert-butylhydroxy-tebuconazole. All compounds were eliminated to below detection limits …


Modeling Escherichia Coli In The Missouri River Near Omaha, Nebraska, 2012–16, Brenda K. Densmore, Brent M. Hall, Matthew T. Moser Jan 2020

Modeling Escherichia Coli In The Missouri River Near Omaha, Nebraska, 2012–16, Brenda K. Densmore, Brent M. Hall, Matthew T. Moser

United States Geological Survey: Publications

The city of Omaha, Nebraska, has a combined sewer system in some areas of the city. In Omaha, Nebr., a moderate amount of rainfall will lead to the combination of stormwater and untreated sewage or wastewater being discharged directly into the Missouri River and Papillion Creek and is called a combined sewer overflow (CSO) event. In 2009, the city of Omaha began the implementation of their Long Term Control Plan (LTCP) to mitigate the effects of CSOs on the Missouri River and Papillion Creek. As part of the LTCP, the city partnered with the U.S. Geological Survey (USGS) in 2012 …


Annotated Bibliography Of Scientific Research On Greater Sage-Grouse Published From 2015 To 2019, Sarah K. Carter, Robert S. Arkle, Heidi L. Bencin, Benjamin R. Harms, Daniel J. Manier, Aaron N. Johnston, Susan L. Phillips, Steven E. Hanser, Zachary H. Bowen Jan 2020

Annotated Bibliography Of Scientific Research On Greater Sage-Grouse Published From 2015 To 2019, Sarah K. Carter, Robert S. Arkle, Heidi L. Bencin, Benjamin R. Harms, Daniel J. Manier, Aaron N. Johnston, Susan L. Phillips, Steven E. Hanser, Zachary H. Bowen

United States Geological Survey: Publications

The greater sage-grouse (Centrocercus urophasianus; hereafter GRSG) has been a focus of scientific investigation and management action for the past two decades. The 2015 U.S. Fish and Wildlife Service listing determination of “not warranted” was in part due to a large-scale collaborative effort to develop strategies to conserve GRSG populations and their habitat and to reduce threats to both. New scientific information augments existing knowledge and can help inform updates or modifications to existing plans for managing GRSG and sagebrush ecosystems. However, the sheer number of scientific publications can be a challenge for managers tasked with evaluating and …


Alluvial-Lacustrine Sedimentation And Volcaniclastic Deposition In An Intracontinental Tectonic Graben: Paleoenvironmental Evolution Of The Neogene Sinanpaşa Basin, West-Central Turkey, Eli̇f Akiska, Baki̇ Erdoğan Varol Jan 2020

Alluvial-Lacustrine Sedimentation And Volcaniclastic Deposition In An Intracontinental Tectonic Graben: Paleoenvironmental Evolution Of The Neogene Sinanpaşa Basin, West-Central Turkey, Eli̇f Akiska, Baki̇ Erdoğan Varol

Turkish Journal of Earth Sciences

This study reports on the Sinanpaşa Basin, a typical example of the Miocene tectonic intracontinental grabens formed in West Anatolia, Turkey. The study reconstructs the paleoenvironmental and paleogeographic history of the graben based on a detailed sedimentological analysis of basin-fill deposits exposed mainly near the graben's northern and southern margins. The sedimentary paleoenvironments in the graben range from basin-margin alluvial fan systems and basin-axis fluvial distributary system to an intrabasinal shallow lake environment surrounded by peat-forming mires, changing from carbonate to more clayey, episodically evaporitic, and shifting its shorelines considerably. The spatial distribution and stratigraphic stacking of these paleoenvironments indicate …


Hyracoidea From The Middle Miocene Hominoid Locality Of Paşalar (Nw Turkey), Martin Pickford, Serdar Mayda, Berna Alpagut, Fatma Arzu Demi̇rel, Ayşegül Şarbak, Tümel Tanju Kaya Jan 2020

Hyracoidea From The Middle Miocene Hominoid Locality Of Paşalar (Nw Turkey), Martin Pickford, Serdar Mayda, Berna Alpagut, Fatma Arzu Demi̇rel, Ayşegül Şarbak, Tümel Tanju Kaya

Turkish Journal of Earth Sciences

Previously available samples of Hyracoidea from Paşalar (MN 6, Middle Miocene), Turkey, have indicated the presence of Pliohyracidae at the site, but the material was too scanty for confident identification. The single upper molar, an upper molar ectoloph fragment and an ascending ramal fragment were too uninformative for determining the taxonomic identity of the fossils, although several names have been proposed in the literature. Additional fossils collected from Paşalar include upper and lower premolars, which help to tie down the affinities of this hyracoid. They are attributed to the genus Prohyrax, but were not named specifically, even though they are …


Assessment Of Element Concentrations In Surface Sediment Samples Fromsığacık Bay (Eastern Aegean), Özde Bakak, Fi̇li̇z Küçüksezgi̇n, Fai̇k Erdeni̇z Özel Jan 2020

Assessment Of Element Concentrations In Surface Sediment Samples Fromsığacık Bay (Eastern Aegean), Özde Bakak, Fi̇li̇z Küçüksezgi̇n, Fai̇k Erdeni̇z Özel

Turkish Journal of Earth Sciences

Concentrations of Al, Fe, As, Co, Cr, Cu, Mn, Ni, Pb, Zn, Hg, and organic carbon, and grain size distribution were investigated in the surface sediments of 7 sampling stations in the Sığacık Bay (western Anatolia) in December 2016. At all of the sampling stations, the concentrations of Pb, Ni, Cr, and As were higher than the average shale values. The highest concentrations of Pb, Cu, Zn, As, and Hg were found at stations near Doğanbey Cape. The possible sources of pollution were evaluated using several parameters: the enrichment factor (Ef), contamination factor (Cf), and contamination degree (Cd). The Ef …


Ashfall Fossil Beds: From Waterhole To Rhino Barn, Sandy Mosel Jan 2020

Ashfall Fossil Beds: From Waterhole To Rhino Barn, Sandy Mosel

University of Nebraska State Museum: Programs Information

Twelve million years ago a volcanic super-eruption in what is now southwestern Idaho created an enormous ashfall that blanketed the Great Plains with several inches of volcanic ash, devastating the local wildlife. Evidence of this geologic event lies within the hills of the Niobrara River Valley in northeast Nebraska, at a place aptly named the Ashfall Fossil Beds State Historical Park. Located near the tiny village of Royal, the Ashfall Park has been developed around a waterhole where animals succumbed after breathing in the volcanic dust. Buried deeply by windblown volcanic ash in the weeks following the eruption, the skeletons …


Fossil Fortunes: Regulating Commercial Paleontology & Incentivizing Fossil Discovery, Ashlee A. Paxton-Turner Jan 2020

Fossil Fortunes: Regulating Commercial Paleontology & Incentivizing Fossil Discovery, Ashlee A. Paxton-Turner

Faculty Scholarship

No abstract provided.


Early Triassic Conchostracans From The Tiryakh-Kobyume Section (Southern Verkhoyansk Region, Republic Of Sakha (Yakutia)), V. V. Zharinova, F. Scholze, V. I. Davydov, R. V. Kutygin Jan 2020

Early Triassic Conchostracans From The Tiryakh-Kobyume Section (Southern Verkhoyansk Region, Republic Of Sakha (Yakutia)), V. V. Zharinova, F. Scholze, V. I. Davydov, R. V. Kutygin

Geosciences Faculty Publications and Presentations

Conchostracans (Crustacea) from the Induan deposits of the Tiryakh-Kobyume section (southern Verkhoyansk region) were studied. We identified the following seven conchostracan species belonging to five genera: Pseudestheria Raymond, 1946; Euestheria Deperet et Mezeran, 1912; Sphaerestheria Novojilov, 1954; Lioestheria Deperet et Mezeran, 1912; Wetlugites Novojilov, 1958. Most of the previously identified species in the Tiryakh-Kobyume region (“Pseudestheria sibirica”, “Ps. tumaryana”, “Ps. kashirtzevi”, and “Sphaeres­theria aldanensis”) were described in the middle of the 20th century from the basal Triassic in the western Verkhoyansk region (Balbuk section). Revision of these species with the use …


Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila Jan 2020

Uptake, Metabolism, And Elimination Of Fungicides From Coated Wheat Seeds In Japanese Quail (Coturnix Japonica), Michael S. Gross, Thomas G. Bean, Michelle L. Hladik, Barnett A. Rattner, Kathryn M. Kuivila

United States Geological Survey: Staff Publications

Pesticides coated to the seed surface potentially pose an ecological risk to granivorous birds that consume incompletely buried or spilled seeds. To assess the toxicokinetics of seeds treated with current-use fungicides, Japanese quail ( Coturnix japonica) were orally dosed with commercially coated wheat seeds. Quail were exposed to metalaxyl, tebuconazole, and fludioxonil at either a low dose (0.0655, 0.0308, and 0.0328 mg/kg of body weight, respectively) or a high dose (0.196, 0.0925, and 0.0985 mg/kg of body weight, respectively). Fungicides were rapidly absorbed and distributed to tissues. Tebuconazole was metabolized into tert-butylhydroxy-tebuconazole. All compounds were eliminated to below detection limits …


Crop Rotations, Tillage And Cover Crops Influences On Soil Health, Greenhouse Gas Emissions And Farm Profitability, Jasdeep Singh Jan 2020

Crop Rotations, Tillage And Cover Crops Influences On Soil Health, Greenhouse Gas Emissions And Farm Profitability, Jasdeep Singh

Electronic Theses and Dissertations

This study assessed the effects of three levels of crop rotation: [2-yr; corn (Zea mays L.)- soybean (Glycine max L.), 3-yr; corn-soybean-oat (Avena sativa L.) or 4-yr; cornsoybean- oat-winter wheat (Triticum aestivum L.)], two tillage [conventional-till (CT) and no-till (NT)], and two winter cover cropping systems [cover crop (CC) or fallow control (NC)] on soil biochemical and physical properties, greenhouse gas emissions (GHG), microbial community composition, crop yield and farm profitability under silty clay loam soil of south eastern South Dakota. Experimental design was a randomized complete block design in a split-split plot treatment arrangement with four replications. Rotations, tillage …


Soil Physical And Hydrological Properties, And Greenhouse Gas Emissions Under Integrated Crop-Livestock Agroecosystems, Navdeep Singh Jan 2020

Soil Physical And Hydrological Properties, And Greenhouse Gas Emissions Under Integrated Crop-Livestock Agroecosystems, Navdeep Singh

Electronic Theses and Dissertations

Cover crops (CCs) and grazing play a critical role in successful implementation of the integrated crop-livestock system (ICLS) because they can have a direct impact on soils and greenhouse gas emissions. The objectives of this study were to (i) evaluate the short-term impacts of CCs [grass dominated cover crops (GdC) and legume dominated cover crops (LdC)] and grazed CCs and corn (Zea mays L.) residue under oat (Avena sativa L.)–CC–corn rotation on soil physical and hydrological properties; (ii) quantify the architecture of soil pores using X-ray computed tomography (CT) for soils managed under long-term ICLS, native grazed pasture and corn-soybean …


Stable Carbon And Oxygen Isotopes As Environmental Indicators Of The Late Pleistocene Inel Arenoso, Sonora, Northwest Mexico, Victor Adrian Perez Crespo, Tamara Cruz Y Cruz, Alejandro Terrazas Mata, Pedro Morales Puente, Martha Benavente, Edith Cienfuegos-Alvrado, Francisco J. Otero Jan 2020

Stable Carbon And Oxygen Isotopes As Environmental Indicators Of The Late Pleistocene Inel Arenoso, Sonora, Northwest Mexico, Victor Adrian Perez Crespo, Tamara Cruz Y Cruz, Alejandro Terrazas Mata, Pedro Morales Puente, Martha Benavente, Edith Cienfuegos-Alvrado, Francisco J. Otero

Turkish Journal of Earth Sciences

The paleoenvironment conditions that existed in the Late Pleistocene at the archaeological-paleontological site of El Arenoso, Sonora, NW Mexico, were inferred using the carbon and oxygen stable isotopes from one bison, one mammoth, and thirteen horses as well as the pedological characteristics and the carbon isotopes of calcium carbonates from paleosoil. The values δ13C of the bison (-1.4‰), the horses (-2.8‰), and the mammoth (-4.3‰) show that these animals fed mainly on C4 plants and carbon isotopic values from profile horizons of locality 4Bgk (-3.4‰), 3Ck (-3.4‰), and 2Bgk2 (-5.7‰) indicated the presence of C3/C4 vegetation mixed in El Arenoso. …


Heavy Metal Contamination In Groundwater And Surface Water Due To Active Pb-Zn-Cumine Tails And Water-Rock Interactions: A Case Study From The Küre Mine Area (Turkey), Tülay Ekemen Keski̇n, Emre Özler Jan 2020

Heavy Metal Contamination In Groundwater And Surface Water Due To Active Pb-Zn-Cumine Tails And Water-Rock Interactions: A Case Study From The Küre Mine Area (Turkey), Tülay Ekemen Keski̇n, Emre Özler

Turkish Journal of Earth Sciences

This study aimed at elucidating the groundwater and surface water pollution resulting from water-rock interaction, mine tailings, and mining activities at Küre (Kastamonu) sulfidic Pb-Zn-Cu mine area and its vicinity. The study area has a surface area of approximately 2990 km2. The Küre River drainage site covering the study area is approximately 440 km2. The concentrations of SO4, Al, As, Ba, Mn, Ni, Sb, and Pb in some groundwater (K10, K20, K21, K27, K28, K29, K30), and surface water (KR3) exceed the maximum limit values with respect to the Turkish Standards for Water Intended For Human Consumption and World Health …


New Geosite Candidates From Urla (İzmir, Western Anatolia, Turkey): A List Of Geologicalassets Nested With Antique And Modern Cultural Heritage, Ökmen Sümer, Mehmet Akbulut, Hülya İnaner Jan 2020

New Geosite Candidates From Urla (İzmir, Western Anatolia, Turkey): A List Of Geologicalassets Nested With Antique And Modern Cultural Heritage, Ökmen Sümer, Mehmet Akbulut, Hülya İnaner

Turkish Journal of Earth Sciences

The Urla Basin is an approximately 20 km wide and 30 km long N-S-trending strike-slip basin, located in the westernmost part of the Western Anatolia Extensional Province. Although the basin-fill units are generally composed of sedimentary and volcanic rocks of Miocene to Recent, Triassic and Late Cretaceous-Paleocene sedimentary rocks are also exposed in the middle and western part of the basin. In addition to this geological diversity, the basin hosts many ancient settlements due to its geographical position and close contact with the Aegean Sea. This study mostly focuses on the northern part of the basin with a concentration on …


Applied Injected Air Into Subsurface Drip Irrigation: Plant Uptake Of Pharmaceuticals And Soil Microbial Communities, Matteo D'Alessio, Lisa M. Durso, Clinton Williams, Christopher A. Olson, Chittaranjan Ray, Ellen Paparozzi Jan 2020

Applied Injected Air Into Subsurface Drip Irrigation: Plant Uptake Of Pharmaceuticals And Soil Microbial Communities, Matteo D'Alessio, Lisa M. Durso, Clinton Williams, Christopher A. Olson, Chittaranjan Ray, Ellen Paparozzi

Nebraska Water Center: Faculty Publications

The growing global food security crisis is complicated by the need for increased crop production with less arable land and limited water resources. Reuse of treated wastewater for agricultural irrigation is becoming more common, often paired with other conservation measures such as subsurface drip irrigation (SDI). Passively injecting air into SDI systems increases crop yields and overcomes root zone wetting issues. However, when used with treated irrigation water, contaminants in the water might be taken up by the crops. This paper investigates the impact of air-injected water containing caffeine, carbamazepine, and gemfibrozil on plant uptake and soil microbial communities in …


Droughtscape, Winter 2019, Cory Matteson Jan 2020

Droughtscape, Winter 2019, Cory Matteson

DroughtScape: Quarterly Newsletter of the National Drought Mitigation Center (2007–2023)

Contents

From the Director

4th quarter climate summary

2019 year in review summary

4th quarter drought impact summary

2019 drought impact summary

New form helps ‘see more’ drought

Landscape photographers invited to submit photos

Helping Central and South America planning

Database includes more drought planning


Scientist Of The Week!, Sarah L. Sheffield, Lisette Melendez, Kristin Houdyshell, Mathew Burgos Jan 2020

Scientist Of The Week!, Sarah L. Sheffield, Lisette Melendez, Kristin Houdyshell, Mathew Burgos

School of Geosciences Faculty and Staff Publications

No abstract provided.


Space-Time Hierarchical Clustering For Identifying Clusters In Spatiotemporal Point Data, David S. Lamb, Joni Downs, Steven Reader Jan 2020

Space-Time Hierarchical Clustering For Identifying Clusters In Spatiotemporal Point Data, David S. Lamb, Joni Downs, Steven Reader

School of Geosciences Faculty and Staff Publications

Finding clusters of events is an important task in many spatial analyses. Both confirmatory and exploratory methods exist to accomplish this. Traditional statistical techniques are viewed as confirmatory, or observational, in that researchers are confirming an a priori hypothesis. These methods often fail when applied to newer types of data like moving object data and big data. Moving object data incorporates at least three parts: location, time, and attributes. This paper proposes an improved space-time clustering approach that relies on agglomerative hierarchical clustering to identify groupings in movement data. The approach, i.e., space–time hierarchical clustering, incorporates location, time, and attribute …


Boosting Computational Effectiveness In Big Spatial Flow Data Analysis With Intelligent Data Reduction, Ran Tao, Zhaoya Gong, Qiwei Ma, Jean-Claude Thill Jan 2020

Boosting Computational Effectiveness In Big Spatial Flow Data Analysis With Intelligent Data Reduction, Ran Tao, Zhaoya Gong, Qiwei Ma, Jean-Claude Thill

School of Geosciences Faculty and Staff Publications

One of the enduring issues of spatial origin-destination (OD) flow data analysis is the computational inefficiency or even the impossibility to handle large datasets. Despite the recent advancements in high performance computing (HPC) and the ready availability of powerful computing infrastructure, we argue that the best solutions are based on a thorough understanding of the fundamental properties of the data. This paper focuses on overcoming the computational challenge through data reduction that intelligently takes advantage of the heavy-tailed distributional property of most flow datasets. We specifically propose the classification technique of head/tail breaks to this end. We test this approach …


Geoscience Videos And Animations: How To Make Them With Your Students, And How To Use Them In The Classroom, Robert J. Stern, Jeff Ryan, Ning Wang, Victor J. Ricchezza, Siloa Willis Jan 2020

Geoscience Videos And Animations: How To Make Them With Your Students, And How To Use Them In The Classroom, Robert J. Stern, Jeff Ryan, Ning Wang, Victor J. Ricchezza, Siloa Willis

School of Geosciences Faculty and Staff Publications

We are in the midst of a “tectonic shift” in the way that undergraduate students want to learn. They will attend lectures and read assignments if they must, but they are especially interested in information that they can receive as videos on their cell phones and other mobile devices (Prensky, 2001; Thomas, 2011). The geosciences are uniquely well-suited to presentation via well-crafted, scientifically robust videos and animations. Geologic processes often take place over thousands to hundreds of millions of years and occur deep under water or within the Earth, where direct observation is not possible. Geology is synonymous with travel: …


Mapping Long-Term Spatiotemporal Dynamics Of Pen Aquaculture In A Shallow Lake: Less Aquaculture Coming Along Better Water Quality, Juhua Luo, Ruiliang Pu, Ronghua Ma, Xiaolong Wang, Xijun Lai, Zhigang Mao, Li Zhang, Zhaoliang Peng, Zhe Sun Jan 2020

Mapping Long-Term Spatiotemporal Dynamics Of Pen Aquaculture In A Shallow Lake: Less Aquaculture Coming Along Better Water Quality, Juhua Luo, Ruiliang Pu, Ronghua Ma, Xiaolong Wang, Xijun Lai, Zhigang Mao, Li Zhang, Zhaoliang Peng, Zhe Sun

School of Geosciences Faculty and Staff Publications

Pen aquaculture is the main form of aquaculture in some shallow lakes in eastern China. It is valuable to map the spatiotemporal changes of pen aquaculture in eutrophic lakes to assess its effect on water quality, thereby helping the relevant decision-making agencies to manage the water quality (WQ) of lakes. In this study, an automatic approach for extracting the pen aquaculture area was developed based on Landsat data. The approach integrates five algorithms, including grey transformation, discrete wavelet transform, fast Fourier transform, singular value decomposition and k-nearest neighbor classification. It was successfully applied in the automatic mapping of the pen …


Late Holocene Droughts And Cave Ice Harvesting By Ancestral Puebloans, Bogdan P. Onac, Steven M. Baumann, Dylan S. Parmenter, Eric Weaver, Tiberiu B. Sava Jan 2020

Late Holocene Droughts And Cave Ice Harvesting By Ancestral Puebloans, Bogdan P. Onac, Steven M. Baumann, Dylan S. Parmenter, Eric Weaver, Tiberiu B. Sava

School of Geosciences Faculty and Staff Publications

Water availability for Native Americans in the southwestern United States during periods of prolonged droughts is poorly understood as regional hydroclimate records are scant or contradicting. Here, we show that radiocarbon-dated charcoal recovered from an ice deposit accumulated in Cave 29, western New Mexico, provide unambiguous evidence for five drought events that impacted the Ancestral Puebloan society between ~ AD 150 and 950. The presence of abundant charred material in this cave indicates that they periodically obtained drinking water by using fire to melt cave ice, and sheds light on one of many human–environment interactions in the Southwest in a …