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Organic Geochemical Characteristics Of Coal Deposits In Lampang Province, Patthapong Chaiseanwang Jan 2019

Organic Geochemical Characteristics Of Coal Deposits In Lampang Province, Patthapong Chaiseanwang

Chulalongkorn University Theses and Dissertations (Chula ETD)

ถ่านหินและหินตะกอนจำนวน 31 ตัวอย่างจากแหล่งถ่านหินแม่ตีบและแหล่งถ่านหินแม่ทานที่ตั้งอยู่ในจังหวัดลำปางทางตอนเหนือของประเทศไทยถูกนำมาศึกษาลักษณะเฉพาะทางธรณีเคมีอินทรีย์ (Organic geochemistry) ผลจากการวิเคราะห์ปริมาณสารอินทรีย์ทั้งหมด (Total organic carbon) พบว่าตัวอย่างถ่านหินจากแหล่งแม่ตีบมีค่าระหว่าง 30.12 - 73.71 wt. % และสูงกว่าตัวอย่างถ่านหินของแหล่งแม่ทานซึ่งมีค่าระหว่าง 23.48 - 52.50 wt. % หินดินดานจากทั้งสองแหล่งมีค่าใกล้เคียงกันระหว่าง 4.82 - 19.49 wt. % ในแหล่งแม่ตีบ และ 14.00 - 24.87 wt. % ในแหล่งแม่ทาน ค่าที่น้อยที่สุดของปริมาณสารอินทรีย์ทั้งหมดปรากฏในตัวอย่างหินโคลนซึ่งมีค่าระหว่าง 0.88 – 4.92 wt. % ในแหล่งแม่ตีบ และค่าระหว่าง 0.59 – 5.98 wt. % การวิเคราะห์ปริมาณสารอินทรีย์ที่สกัดได้ (Extractable organic matter) ในตัวอย่างหินของแหล่งแม่ตีบมีค่าระหว่าง 1,277 - 9,764 ppm ในขณะที่ตัวอย่างหินของแหล่งแม่ทานมีค่ามากกว่าโดยอยู่ระหว่าง 1,256-16,421 ppm จากข้อมูลข้างต้นทั้งสองแหล่งมีศักยภาพการเป็นชั้นหินต้นกำเนิดของแหล่งปิโตรเลียมอยู่ในเกณฑ์ดีถึงดีเยี่ยมยกเว้นหินโคลนบางตัวอย่าง ข้อมูลลักษณะเฉพาะทางธรณีเคมีอินทรีย์ศึกษาจากแก๊สโครมาโตแกรม (Gas chromatogram) ได้มาจากการวิเคราะห์โดยใช้เครื่องมือแก๊สโครมาโตกราฟี-แมสสเปกโตมิเตอร์ (Gas chromatography-mass spectrometer) ซึ่งให้ข้อมูลของตัวชี้วัดทางชีวภาพ (Biomarker and non-biomarker) ที่มีประโยชน์ในการตีความทั้งระดับความพร้อมสมบูรณ์ (Maturity) ชนิดของอินทรีย์วัตถุ (Organic matter input) และสภาพแวดล้อมการสะสมตัวในอดีต (Depositional environment) ในการศึกษานี้ถ่านหินมีระดับความพร้อมสมบูรณ์เทียบเคียงกับระดับถ่านหิน (coal rank) อยู่ในระดับลิกไนต์ถึงบิทูมินัสสารระเหยสูงระดับซี (Lignite – high volatile bituminous C) อ้างอิงจากตัวชี้วัดความพร้อมสมบูรณ์ทางชีวภาพ (Biomarker maturity) ซึ่งบ่งชี้ว่าตัวอย่างหินมีระดับความพร้อมสมบูรณ์อยู่ในระดับตอนต้น (immature-early mature stage) แก๊สโครมาโตแกรมของแอลเคนสายตรง (n-alkanes) …


Manufactured By Nature: Growing Generatively Designed Products, Mohammad Jawad Jan 2019

Manufactured By Nature: Growing Generatively Designed Products, Mohammad Jawad

Theses and Dissertations

Mass production and assembly lines are yesterday’s manufacturing methods. They have exhausted Earth’s resources and limited the possibilities of design in terms of both form and material, prompting designers to search for new processes. A new generation of making includes biomimicry-inspired technologies such as 3D printing and parametric simulation, which have transformed the production paradigm. Utilizing nature as industry, this thesis explores the possibility of “growing” designed objects by employing nature’s own processes and resources. It integrates bio materials, generative design and additive manufacturing to produce objects for a post-industrial world. The project outcomes employ natural minerals, crystallization and 3D …


Discerning The Diets Of Sweep-Feeding Eurypterids Through Analyses Of Mesh-Modified Appendage Armature, Emily Samantha Hughes Jan 2019

Discerning The Diets Of Sweep-Feeding Eurypterids Through Analyses Of Mesh-Modified Appendage Armature, Emily Samantha Hughes

Graduate Theses, Dissertations, and Problem Reports (ETD)

Eurypterids were a group of aquatic chelicerates that lived throughout most of the Paleozoic. While swimming eurypterids are generally considered to be active predators, the benthic stylonurine eurypterids appear to have had a mode of life similar to modern horseshoe crabs with the exception of two clades, the Stylonuroidea and the Mycteropoidea, both of which independently evolved modifications for sweep-feeding on their anterior appendages. Among extant suspension feeders, it has been shown that there is a linear correlation between the average spacing of feeding structures and prey sizes. This relationship was extrapolated to the sweep-feeding stylonuroid and mycteropoid eurypterids in …


Research On Land Use Changes And Ecological Risk Assessment In Yongjiang River Basin In Zhejiang Province, China, Peng Tian, Jianlin Li, Hongbo Gong, Ruiliang Pu, Luodan Cao, Shuyao Shao, Zuoqi Shi, Xuili Feng, Lijia Wang, Riuqing Liu Jan 2019

Research On Land Use Changes And Ecological Risk Assessment In Yongjiang River Basin In Zhejiang Province, China, Peng Tian, Jianlin Li, Hongbo Gong, Ruiliang Pu, Luodan Cao, Shuyao Shao, Zuoqi Shi, Xuili Feng, Lijia Wang, Riuqing Liu

School of Geosciences Faculty and Staff Publications

Studying land use changes and ecological risk assessment in Yongjiang River Basin in Zhejiang Province, China, provides theoretical references for optimal configuration of land resources and maintaining stability of ecosystems. Given impacts of land use changes on landscape patterns in the Yongjiang River Basin, ecological risk assessment indexes were constructed and used to analyze temporal and spatial variation characteristics of ecological risk within different periods. Results show that (1) the construction land area was increased quickly, while the cultivated area decreased sharply. A prominent characteristic of land use changes was manifested by transforming cultivated area and forestland into construction land. …


Geochronology And Depositional History Of The Sandy Springs Aeolian Landscape In The Unglaciated Upper Ohio River Valley, United States, Mathew P. Purtill, J. Steven Kite, Steven L. Forman Jan 2019

Geochronology And Depositional History Of The Sandy Springs Aeolian Landscape In The Unglaciated Upper Ohio River Valley, United States, Mathew P. Purtill, J. Steven Kite, Steven L. Forman

Faculty & Staff Scholarship

The study of active and stabilized late Quaternary aeolian landforms provides important proxies for past climate events and environmental transitions. Despite an overall increase in the study of aeolian landforms in previously glaciated and coastal settings in eastern North America, the history of aeolian sedimentation in many unglaciated inland alluvial settings remain poorly understood. This study reports on the geochronology and depositional history of aeolian landforms and sediments in the unglaciated upper Ohio Valley at the Sandy Springs site. Aeolian landforms and sediments include complex, linear, barchan-like, and climbing dunes; an interdune sand sheet; and sandy loess that blankets high …


Historic Log Buildings As Archives Of Past Forest Ecology, Kristen K. De Graauw Jan 2019

Historic Log Buildings As Archives Of Past Forest Ecology, Kristen K. De Graauw

Graduate Theses, Dissertations, and Problem Reports (ETD)

This dissertation is composed of three separate but related manuscripts with the common theme of using historic log buildings from the central Appalachian Mountain region of eastern North America as ecological archives. In Chapter 1, I explore the biases, limitations, and ecological applications of tree-ring data from historic log buildings. European immigrants selected trees from a forested stand based on species, log sizes, and construction locations. Despite this selection bias, ecological information can be gleaned from historic log buildings, which offer a complementary record of past forest ecology and represent a site type that is not often associated with old-growth …


Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch Jan 2019

Cosmic Ray Sensors For The Continuous Measurement Of Arctic Snow Accumulation And Melt, Anton Jitnikovitch

Theses and Dissertations (Comprehensive)

In the Arctic, winter persists for much of the year, resulting in a hydrological system that is primarily regulated by snow and snowmelt runoff, and has important implications on vegetation, animals, and on the thermal regime of the active layer and permafrost. Snow water equivalent (SWE) measurements such as remote sensing techniques provide coarse resolution data, while snow surveys and snow-pits are labour intensive, have limited spatial coverage and do not provide a continuous reading. Over the last few decades, cosmic ray sensors (CRS) have been proposed as a way to provide much improved snow data, but few studies have …


Temporal Changes Of Nutrients Within The Lower Grand River Watershed And Selected Sites, Weston Scott Duley Jan 2019

Temporal Changes Of Nutrients Within The Lower Grand River Watershed And Selected Sites, Weston Scott Duley

Masters Theses

"This report presents the results of a study carried out in collaboration with the U.S. Geological Survey (USGS) and the Missouri Department of Natural Resources (MDNR) to estimate total nitrogen (TN) and total phosphorus (TP) at five USGS monitoring sites within Lower Grand River Watershed (LGRW) and two monitoring sites on the Missouri River. The objective of this study was to quantify temporal changes in TN and TP concentrations and compare those to best management practices (BMPs).

In this study, the approach to the analysis of long-term surface water-quality data by using Weighted Regressions on Time, Discharge and Seasons models …


Continued Eastward Range Expansion Of Black Phoebes (Sayornis Nigricans) In Southernmost Texas, Samuel G. Ortiz, Christopher A. Gabler, Timothy Brush Jan 2019

Continued Eastward Range Expansion Of Black Phoebes (Sayornis Nigricans) In Southernmost Texas, Samuel G. Ortiz, Christopher A. Gabler, Timothy Brush

School of Earth, Environmental, & Marine Sciences Faculty Publications

ABSTRACT—We observed black phoebe (Sayornis nigricans) nests, breeding pairs, and juveniles in Cameron County, Texas, in 2017. Our first confirmed nesting records in Cameron County document a continued eastward range expansion by black phoebes.

RESUMEN—En el 2017, observamos nidos, parejas reproductoras y juveniles del pajaro mosquero negro (Sayornis nigricans) en el condado de Cameron, Texas. Los primeros registros confirmados de reproducci ´on en el condado de Cameron son evidencia de una continua expansion hacia el este de la distribuci ´on geogr´afica del mosquero negro.


Floodplains Provide Important Amphibian Habitat Despite Multiple Ecological Threats, Meredith Holgerson, Adam Duarte, Marc P. Hayes, Michael J. Adams, Julie A. Tyson, Keith A. Douville, Angela L. Strecker Jan 2019

Floodplains Provide Important Amphibian Habitat Despite Multiple Ecological Threats, Meredith Holgerson, Adam Duarte, Marc P. Hayes, Michael J. Adams, Julie A. Tyson, Keith A. Douville, Angela L. Strecker

Environmental Science and Management Faculty Publications and Presentations

Floodplain ponds and wetlands are productive and biodiverse ecosystems, yet they face multiple threats including altered hydrology, land use change, and non-native species. Protecting and restoring important floodplain ecosystems requires understanding how organisms use these habitats and respond to altered environmental conditions. We developed Bayesian models to evaluate occupancy of six amphibian species across 103 off-channel aquatic habitats in the Chehalis River floodplain, Washington State, USA. The basin has been altered by changes in land use, reduced river–wetland connections, and the establishment of non-native American bullfrogs (Rana catesbeiana = Lithobates catesbeianus) and centrarchid fishes, all of which we hypothesized could …


Post-Wildfire Recovery Of An Upland Oak-Pine Forest On The Cumberland Plateau, Kentucky, Usa, Devin E. Black, Zachary W. Poynter, Claudia A. Cotton, Suraj Upadhaya, David D. Taylor, Wendy Leuenberger, Beth A. Blankenship, Mary A. Arthur Dec 2018

Post-Wildfire Recovery Of An Upland Oak-Pine Forest On The Cumberland Plateau, Kentucky, Usa, Devin E. Black, Zachary W. Poynter, Claudia A. Cotton, Suraj Upadhaya, David D. Taylor, Wendy Leuenberger, Beth A. Blankenship, Mary A. Arthur

Forestry and Natural Resources Faculty Publications

Background: Many forests within the southern Appalachian region, USA, have experienced decades of fire exclusion, contributing to regeneration challenges for species such as oaks (Quercus spp. L.) and pines (Pinus spp. L.), and threatening the maintenance of oak-dominated forests in the future. While the use of prescribed fire as a forest management tool is increasing within this region, there remains a lack of information on the potential role of wildfire. A wildfire within the Daniel Boone National Forest, Kentucky, USA, provided an opportunity to investigate how wildfire affected forest vegetation response.

Results: We examined the effects of fire …


Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe Dec 2018

Seasonality Of Nitrogen Balances In A Mediterranean Climate Watershed, Oregon, Us, Jiajia Lin, Jana E. Compton, Scott G. Leibowitz, George Mueller-Warrant, William Matthews, Stephen H. Schoenholtz, Daniel M. Evans, Rob A. Coulombe

United States Environmental Protection Agency: Publications

We constructed a seasonal nitrogen (N) budget for the year 2008 in the Calapooia River Watershed (CRW), an agriculturally dominated tributary of the Willamette River (Oregon, U.S.) under Mediterranean climate. Synthetic fertilizer application to agricultural land (dominated by grass seed crops) was the source of 90% of total N input to the CRW. Over 70% of the stream N export occurred during the wet winter, the primary time of fertilization and precipitation, and the lowest export occurred in the dry summer. Averaging across all 58 tributary subwatersheds, 19% of annual N inputs were exported by streams, and 41% by crop …


The Relationship Between The Phosphate And Structural Carbonate Fractionation Of Fallow Deer Bioapatite In Tooth Enamel, Holly Miller, Carolyn Chenery, Angela L. Lamb, Hilary Sloane, Ruth F. Carden, Levent Atici, Naomi Sykes Dec 2018

The Relationship Between The Phosphate And Structural Carbonate Fractionation Of Fallow Deer Bioapatite In Tooth Enamel, Holly Miller, Carolyn Chenery, Angela L. Lamb, Hilary Sloane, Ruth F. Carden, Levent Atici, Naomi Sykes

Anthropology Faculty Research

Rationale The species‐specific relationship between phosphate (δ18OP values) and structural carbonate (δ18OC values) oxygen isotope ratios has been established for several modern and fossil animal species but until now it has not been investigated in European fallow deer (Dama dama dama). This study describes the relationship between phosphate and structural carbonate bioapatite in tooth enamel of extant fallow deer, which will help us further understand the species' unique environmental and cultural history. Methods The oxygen isotope composition of phosphate (δ18OP value) and structural carbonate (δ18OC value) of hydroxylapatite was determined in 51 modern fallow deer tooth enamel samples from across …


Spoil Type Influences Soil Genesis And Forest Development On An Appalachian Surface Coal Mine Ten Years After Placement, Kenton L. Sena, Carmen T. Agouridis, Jarrod Miller, Christopher D. Barton Dec 2018

Spoil Type Influences Soil Genesis And Forest Development On An Appalachian Surface Coal Mine Ten Years After Placement, Kenton L. Sena, Carmen T. Agouridis, Jarrod Miller, Christopher D. Barton

Lewis Honors College Faculty Publications

Surface mining for coal (or other mineral resources) is a major driver of land-use change around the world and especially in the Appalachian region of the United States. Intentional and well-informed reclamation of surface-mined land is critical for the restoration of healthy ecosystems on these disturbed sites. In Appalachia, the pre-mining land cover is predominately mixed hardwood forest, with rich species diversity. In recent years, Appalachian mine reforestation has become an issue of concern, prompting the development of the Forestry Reclamation Approach, a series of mine reforestation recommendations. One of these recommendations is to use the best available soil substitute; …


Riverbank Filtration Impacts On Post Disinfection Water Quality In Small Systems—A Case Study From Auburn And Nebraska City, Nebraska, Matteo D'Alessio, Bruce Dvorak, Chittaranjan Ray Dec 2018

Riverbank Filtration Impacts On Post Disinfection Water Quality In Small Systems—A Case Study From Auburn And Nebraska City, Nebraska, Matteo D'Alessio, Bruce Dvorak, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

Small water systems can experience a fluctuating quality of water in the distribution system after disinfection. As chlorine is the most common disinfectant for small systems, the occurrence of disinfection byproducts (DBPs) represents a common problem for these systems. Riverbank filtration (RBF) can be a valuable solution for small communities located on riverbanks. The objectives of this study were to evaluate (i) the improvements in water quality at two selected RBF systems, and (ii) the potential lower concentrations of DBPs, in particular, trihalomethanes (THMs), in small systems that use RBF. Two small communities in Nebraska, Auburn and Nebraska City, using …


Prokaryotic Diversity And Aqueous Geochemistry Of Subsurface Environments Of The Death Valley Regional Flow System, Joshua David Sackett Dec 2018

Prokaryotic Diversity And Aqueous Geochemistry Of Subsurface Environments Of The Death Valley Regional Flow System, Joshua David Sackett

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation summarizes over four years of effort towards the completion of a Ph.D. in Biological Sciences. The work presented in this document covers a broad range of topics, but a central unifying theme is prokaryotic life in the continental subsurface. The work presented in each chapter relied heavily on cultivation-independent methods for assessing prokaryotic communities, including prokaryotic community structure reconstruction from high-throughput sequencing of 16S rRNA gene libraries and single-cell genome analysis of novel uncultivated bacteria.

Chapter 2 examines the aqueous geochemistry and prokaryotic diversity of Devils Hole, a cavernous limnocrene and sole natural habitat for the critically endangered …


Assessing The Feasibility Of Soil Infiltration Trenches For Highway Runoff Control On The Island Of Oahu, Hawaii, Martina Sobotkova, Jaromir Dusek, Ghasem Alavi, Laxman Sharma, Chittaranjan Ray Dec 2018

Assessing The Feasibility Of Soil Infiltration Trenches For Highway Runoff Control On The Island Of Oahu, Hawaii, Martina Sobotkova, Jaromir Dusek, Ghasem Alavi, Laxman Sharma, Chittaranjan Ray

Daugherty Water for Food Global Institute: Faculty Publications

The coastal waters of Hawaii are extremely important for recreation as well as for the health of the marine environment. Non-point source pollution from storm runoff poses a great threat to surface water quality in Hawaii. The State of Hawaii Department of Transportation (HDOT) includes infiltration trenches as a best management practice (BMP) option to reduce pollution caused by stormwater runoff. HDOT guidelines state that the implementation of BMPs is needed to reduce sediment and pollutant loads to streams and the ocean. In this study, the suitability of soils adjacent to highways on Oahu for the siting of infiltration trenches …


Pengaruh Cara Pemberian Pupuk Organik Cair Vinasse Terhadap Pertumbuhan Awal Bawang Dayak (Eleutherine Palmifolia), Rina Ekawati, Lestari Hetalesi Saputri Dec 2018

Pengaruh Cara Pemberian Pupuk Organik Cair Vinasse Terhadap Pertumbuhan Awal Bawang Dayak (Eleutherine Palmifolia), Rina Ekawati, Lestari Hetalesi Saputri

Jurnal Kultivasi

Pupuk organik bermanfaat untuk meningkatkan kandungan hara, bahan organik tanah, serta memperbaiki sifat fisik, kimia, dan biologi tanah. Vinasse merupakan limbah dari proses pembuatan bioetanol pada industri pengolahan gula, jika telah mengalami proses pengomposan dapat digunakan sebagai pupuk organik cair (POC) vinasse yang dapat meningkatkan pertumbuhan tanaman. Bawang dayak merupakan salah satu tanaman hortikultura yang dapat dijadikan sebagai tanaman berkhasiat obat. Penelitian ini bertujuan untuk mempelajari pengaruh cara pemberian pupuk organik cair vinasse terhadap pertumbuhan awal tanaman bawang dayak. Percobaan ini dilakukan di Politeknik Lembaga Pendidikan Perkebunan (LPP) Yogyakarta, dari bulan Juli hingga November 2018. Penelitian ini menggunakan rancangan acak …


Widespread, Prolonged Microbial Limestone Deposition And Large, Rapid Sulfur Isotope Excursions: A New Perspective On The Early Triassic From The Western U.S., Brad M. Jeffrey Dec 2018

Widespread, Prolonged Microbial Limestone Deposition And Large, Rapid Sulfur Isotope Excursions: A New Perspective On The Early Triassic From The Western U.S., Brad M. Jeffrey

Earth and Planetary Sciences ETDs

The Early Triassic records a ~5 My period of marine biological recovery following the end-Permian mass extinction (EPME, ~252 My). Global oceans were characterized by warm sea-surface temperatures (SSTs), widespread anoxia, and major perturbations to the carbon cycle, the collective result of repeated massive Siberian Traps eruptions and associated global climate feedbacks. Globally widespread microbial deposits (stromatolites, thrombolites) developed in shallow marine environments. Several marine isotope records (C, O, S, U) indicate repeated, large-magnitude shifts related to paleoceanographic events during the recovery of marine ecosystems following the EPME.

Chapter 1 describes and interprets a widespread (~400 km along strike) Smithian …


Simulating The Impacts Of Irrigation Levels On Soybean Production In Texas High Plains To Manage Diminishing Groundwater Levels, Vaishali Sharda, Prasanna H. Gowda, Gary Marek, Isaya Kisekka, Chittaranjan Ray, Pradip Adhikari Dec 2018

Simulating The Impacts Of Irrigation Levels On Soybean Production In Texas High Plains To Manage Diminishing Groundwater Levels, Vaishali Sharda, Prasanna H. Gowda, Gary Marek, Isaya Kisekka, Chittaranjan Ray, Pradip Adhikari

Nebraska Water Center: Faculty Publications

There is an increasing need to strategize and plan irrigation systems under varied climatic conditions to support efficient irrigation practices while maintaining and improving the sustainability of groundwater systems. This study was undertaken to simulate the growth and production of soybean [Glycine max (L.)] under different irrigation scenarios. The objectives of this study were to calibrate and validate the CROPGRO-Soybean model under Texas High Plains’ (THP) climatic conditions and to apply the calibrated model to simulate the impacts of different irrigation levels and triggers on soybean production. The methodology involved combining short-term experimental data with long-term historical weather data (1951–2012), …


Assessment Of The Effects Of Climate Change On Evapotranspiration With An Improved Elasticity Method In A Nonhumid Area, Lei Tian, Jiming Jin, Pute Wu, Guo-Yue Niu Dec 2018

Assessment Of The Effects Of Climate Change On Evapotranspiration With An Improved Elasticity Method In A Nonhumid Area, Lei Tian, Jiming Jin, Pute Wu, Guo-Yue Niu

Watershed Sciences Faculty Publications

Climatic elasticity is a crucial metric to assess the hydrological influence of climate change. Based on the Budyko equation, this study performed an analytical derivation of the climatic elasticity of evapotranspiration (ET). With this derived elasticity, it is possible to quantitatively separate the impacts of precipitation, air temperature, net radiation, relative humidity, and wind speed on ET in a watershed. This method was applied in the Wuding River Watershed (WRW), located in the center of the Yellow River Watershed of China. The estimated rate of change in ET caused by climatic variables is −10.69 mm/decade, which is close to the …


Designing A Protected Area To Safeguard Imperiled Species From Urbanization, Stephanie S. Romanach, Brad Stith, Fred A. Johnson Dec 2018

Designing A Protected Area To Safeguard Imperiled Species From Urbanization, Stephanie S. Romanach, Brad Stith, Fred A. Johnson

United States Geological Survey: Staff Publications

Reserve design is a process that can address ecological, social, and political factors to identify parcels of land needed to sustain wildlife populations and other natural resources. Acquisition of parcels for a large terrestrial reserve is difficult because it typically occurs over a long timeframe and thus invokes consideration of future conditions such as climate and urbanization changes. In central Florida, the U.S. government has authorized a new protected area, the Everglades Headwaters National Wildlife Refuge. The new refuge will host important threatened and endangered species and habitats, and will be located to allow for species adaptation from climate change …


An Early Late Cretaceous Nodosaur From The Marine Eagle Ford Group Of North Central Texas, A Test Of The Endothermy In The Mosasaurs From The Late Cretaceous Of Angola, And The Ontogeny Of A New Pipid Frog From The Miocene Of Ethiopia, Matt Clemens Dec 2018

An Early Late Cretaceous Nodosaur From The Marine Eagle Ford Group Of North Central Texas, A Test Of The Endothermy In The Mosasaurs From The Late Cretaceous Of Angola, And The Ontogeny Of A New Pipid Frog From The Miocene Of Ethiopia, Matt Clemens

Earth Sciences Theses and Dissertations

The first two chapters of this dissertation detail the study of the newly recovered Holland Farm nodosaur (SMU 77100) from the Eagle Ford Group (95.29 ± 0.04 MA) of Mansfield in north central Texas. The objectives of this research are (1) to describe the anatomy of the Holland Farm nodosaur, (2) to determine its phylogenetic position within Ankylosauria, (3) to elaborate the substantial differences in body size and osteoderm morphology in armored dinosaurs occurring in north central Texas during the short duration of the Late Albian and Early Cenomanian, and (4) to provide a radiometric date for the lowermost member …


Fusulinid And Conodont Biostratigraphy Of The Upper Pennsylvanian–Cisuralian Riepe Spring Limestone, Spruce Mountain Ridge, Elko County, Nevada, U.S.A., Michael Taylor Read Dec 2018

Fusulinid And Conodont Biostratigraphy Of The Upper Pennsylvanian–Cisuralian Riepe Spring Limestone, Spruce Mountain Ridge, Elko County, Nevada, U.S.A., Michael Taylor Read

Earth & Environmental Sciences Dissertations - Archive

The Upper Pennsylvanian-Cisuralian (lower Permian) mixed carbonate-siliciclastic strata exposed at Spruce Mountain Ridge, Elko County, Nevada, record the shallow-marine microfauna and oscillating depositional history of the Ferguson Trough during the final glacial interval of the late Paleozoic ice age. The 420 m thick North Spruce Mountain Ridge (NSMR) section includes the uppermost part of the Ely Limestone, the Riepe Spring Limestone, and the base of the Rib Hill Formation. A discontinuous Pennsylvanian-Permian transition is preserved within the approximately 390 m thick Riepe Spring Limestone along the west side of Spruce Mountain Ridge, where an erosional disconformity separates upper Gzhelian (Upper …


Assessment Of Soil Properties And Vegetation In A Mounded Native Tallgrass Prairie With An Aquic And Udic Soil Moisture Regime In The Ozark Highlands Region Of Northwest Arkansas, Tyler Joseph Durre Dec 2018

Assessment Of Soil Properties And Vegetation In A Mounded Native Tallgrass Prairie With An Aquic And Udic Soil Moisture Regime In The Ozark Highlands Region Of Northwest Arkansas, Tyler Joseph Durre

Graduate Theses and Dissertations

Native tallgrass prairies were once considered to be the dominant pre-settlement vegetation type in the eastern third of the Great Plains, but are now designated as America’s most endangered ecosystem due to conversion to agricultural land. Prairie mounds are unique soil features still present in remnant native tallgrass prairies across the United States. The main objective was to determine the effects of soil moisture regime (i.e., aquic and udic), mound position, (i.e., mound summit, backslope, toeslope, inter-mound), soil depth (i.e., 10-cm intervals from 0 to 90 cm), and their interactions on soil physical, chemical, and hydraulic properties in a mounded …


Margaret White Springs Recharge Study, Buffalo National River, North-Central Arkansas, Usa, Ashlon Elizabeth Leonard Dec 2018

Margaret White Springs Recharge Study, Buffalo National River, North-Central Arkansas, Usa, Ashlon Elizabeth Leonard

Graduate Theses and Dissertations

Margaret White Springs (MWS) is one of the largest springs in the middle section of the Buffalo National River (BNR) and contributes several tens of cubic feet per second of flow to river discharge on average, yet the source of the water has not been fully studied or documented. The spring is located approximately 4 miles downstream from Robertson Hole, a losing reach of the river. At Robertson Hole the river loses a significant amount of flow to groundwater, which during the dry season (summer) can be as much as 100%. Flow in the main channel is re-established at MWS; …


Carbon Sequestration In Grassland Soils Across Arkansas, Marya Jean Mckee Dec 2018

Carbon Sequestration In Grassland Soils Across Arkansas, Marya Jean Mckee

Graduate Theses and Dissertations

The capture, conversion, and long-term storage of carbon dioxide (CO2) as soil organic carbon (SOC), a process known as soil C sequestration, is a possible solution to the current and ever-increasing threat of rising greenhouse gas emissions and global climate change. Tallgrass prairies, which once historically covered the country, are known to accumulate and sequester large amounts of C from the atmosphere deep within the soil, due to their extensive rooting systems. The purpose of this research was to increase understanding of soil C sequestration dynamics and general functioning in disappearing native grassland ecosystems within Arkansas, as well as the …


Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy Dec 2018

Managing For Vegetation Heterogeneity On Rangelands: An Exploration Of Rancher Attitudes, Stephanie Marie Kennedy

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

Grasslands provide food, fiber, and numerous ecosystem services to human populations as well as habitat for wildlife. They are also some of the most endangered ecosystems in the world because of their productive soils and open topography. This problem is exacerbated by the accelerating conversion of grassland to cropland and encroaching trees and shrubs. The quality of remaining grasslands will be of increasing importance because of the biodiversity and vital ecosystem services they provide. Heterogeneity is a term specific to rangeland science that is illustrative of grassland health. Grassland species require very specific and differing habitats and without the variation …


The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams Dec 2018

The Biological Significance And Utility Of Feeding By Dermestes Maculatus, Braymond Adams

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

With their efficient feeding habits and tolerance to very low moisture and humidity, beetles in the Family Dermestidae are especially adapted to variable environments and habitats. Dermestid cultures have been in use since 1922 in cleaning tissue and flesh from bones, and proven benefit in multiple fields, including zoology, ornithology, and forensics. Dermestid feeding behaviors when coupled with known life stage and insect succession information aids in providing significant entomological evidence. However, the feeding activities of insects, like those of vertebrate scavengers and predators, change remains and may leave artifacts that can be sometimes be difficult to assign to a …


Stable Isotope Geochemistry Of Bioapatite, Amanda E. Drewicz Dec 2018

Stable Isotope Geochemistry Of Bioapatite, Amanda E. Drewicz

Boise State University Theses and Dissertations

The Cenozoic Era was a time period where dynamic shifts in climate created for both warm-wet greenhouse environments of the mid-Miocene Climatic Optimum (MMCO), and cool-dry, glacial periods of the late Pleistocene. The Cenozoic is close to our own time period, and although past climate reconstructions cannot be used as direct analogs for future climate change, understanding previous environmental responses can help inform policy surrounding future climate change. Presented here are climate reconstructions of the interior western United States, from two different geologic time periods. Each had a different climate, that differed greatly from modern day environments. The use of …