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Articles 13051 - 13080 of 17799
Full-Text Articles in Entire DC Network
Ecohydrology And Groundwater Dynamics In A Salt Marsh Island, Andrea L. H. Hughes
Ecohydrology And Groundwater Dynamics In A Salt Marsh Island, Andrea L. H. Hughes
Theses and Dissertations
Tidal salt marshes are extraordinarily productive and valuable ecosystems that provide via groundwater a not insignificant portion of coastal solute and nutrient budgets. Among the many goods and services they provide are habitat for diverse wildlife, protection for coastal communities during storms, and protection for coastal surface waters by filtering anthropogenic pollutants. One threat to the health of tidal salt marshes along the East Coast have been episodes of Acute Marsh Dieback (AMD) from 1999 to 2001. Dieback was observed at North Inlet salt marsh from 2000 to 2001. Since salt marsh hydrology is dominated by the local tidal regime, …
Satellite-Assisted Assessment Of The Effects Of Human Development On Coral Reefs, Roatan Honduras, Clayton A. Helm
Satellite-Assisted Assessment Of The Effects Of Human Development On Coral Reefs, Roatan Honduras, Clayton A. Helm
Theses and Dissertations
Human intervention is degrading coastal marine environments on a global scale. Coral reefs are one of the most valuable ecosystems occupying coastal areas that provide a vast majority of consumable fish, recreational activities, and protection from extreme events, such as tropical cyclones. Unfortunately, as human development activities such as the construction of buildings, road infrastructure, and agriculture increase in coastal areas, so do the detrimental impacts on the health of coral reefs. Consequences of coastal development such as pollution, sedimentation, eutrophication, overfishing, and recreational activities have been linked to diminished coral health. A degraded coral ecosystem can often be identified …
An Association Between A Cusk Eel (Bassozetus Sp.) And A Black Coral (Schizopathes Sp.) In The Deep Western Indian Ocean, Andrew R. Gates, Kirsty J. Morris, Daniel O. Jones, Kenneth J. Sulak
An Association Between A Cusk Eel (Bassozetus Sp.) And A Black Coral (Schizopathes Sp.) In The Deep Western Indian Ocean, Andrew R. Gates, Kirsty J. Morris, Daniel O. Jones, Kenneth J. Sulak
United States Geological Survey: Staff Publications
Detailed observations in the deep sea can reveal previously unknown behaviour, species interactions and fine-scale habitat heterogeneity. Here, the first in situ images of the black coral Schizopathes sp. (Anthozoa: Antipatharia) in the deep western Indian Ocean have been obtained from remotely operated vehicle video footage and time-lapse photography. In these images, there appears to be an association with the cusk eel Bassozetus (Family: Ophidiidae). In the primary observation, chance encounters revealed the fish interacted with the anitpatharian on multiple occasions over several days. Subsequent time-lapse camera footage showed the fish remained almost exclusively underneath the antipatharian for the duration …
The Influences Of Drought And Land-Cover Conversion On Inter-Annual Variation Of Npp In The Three-North Shelterbelt Program Zone Of China Based On Modis Data, Dailiang Peng, Chaoyang Wu, Bing Zhang, Alfredo Huete, Xiaoyang Zhang, Rui Sun, Liping Lei, Wenjing Huang, Liangyun Liu, Xinjie Liu, Jun Li, Shezhou Luo, Bin Fang
The Influences Of Drought And Land-Cover Conversion On Inter-Annual Variation Of Npp In The Three-North Shelterbelt Program Zone Of China Based On Modis Data, Dailiang Peng, Chaoyang Wu, Bing Zhang, Alfredo Huete, Xiaoyang Zhang, Rui Sun, Liping Lei, Wenjing Huang, Liangyun Liu, Xinjie Liu, Jun Li, Shezhou Luo, Bin Fang
GSCE Faculty Publications
Terrestrial ecosystems greatly contribute to carbon (C) emission reduction targets through photosynthetic C uptake.Net primary production (NPP) represents the amount of atmospheric C fixed by plants and accumulated as biomass. The Three-North Shelterbelt Program (TNSP) zone accounts for more than 40% of China’s landmass. This zone has been the scene of several large-scale ecological restoration efforts since the late 1990s, and has witnessed significant changes in climate and human activities.Assessing the relative roles of different causal factors on NPP variability in TNSP zone is very important for establishing reasonable local policies to realize the emission reduction targets for central government. …
Mineralogical Transformations And Soil Development In Shale Across A Latitudinal Climosequence, Ashlee L.D. Dere, Timothy S. White, Richard H. April, Susan L. Brantley
Mineralogical Transformations And Soil Development In Shale Across A Latitudinal Climosequence, Ashlee L.D. Dere, Timothy S. White, Richard H. April, Susan L. Brantley
Geography and Geology Faculty Publications
To investigate factors controlling soil formation, we established a climosequence as part of the Susquehanna-Shale Hills Critical Zone Observatory (SSHCZO) in central Pennsylvania, USA. Sites were located on organic matter-poor, iron-rich Silurian-aged shale in Wales, Pennsylvania, Virginia, Tennessee, Alabama, and Puerto Rico, although this last site is underlain by a younger shale. Across the climosequence, mean annual temperature (MAT) increases from 7 to 24°C and mean annual precipitation (MAP) ranges from 100 to 250 cm. Variations in soil characteristics along the climosequence, including depth, morphology, particle-size distribution, geochemistry, and bulk and clay mineralogy, were characterized to investigate the role of …
The Influence Of Floodplain Restoration On Flow And Sediment Dynamics In An Urban River, Sangaralingam Ahilan, Mingfu Guan, Andrew Sleigh, Nigel G. Wright, Heejun Chang
The Influence Of Floodplain Restoration On Flow And Sediment Dynamics In An Urban River, Sangaralingam Ahilan, Mingfu Guan, Andrew Sleigh, Nigel G. Wright, Heejun Chang
Geography Faculty Publications and Presentations
A study of floodplain sedimentation on a recently restored floodplain is presented. This study uses a two-dimensional hydro-morphodynamic model for predicting flow and suspended-sediment dynamics in the downstream of Johnson Creek, the East Lents reach, where the bank of the river has been reconfigured to reconnect to a restored floodplain on a 0.26 km2 (26-ha) site. The simulation scenarios include 10-, 50-, 100- and 500-year event-based deposition modelling of flood events and long-term modelling using the 64 historical flood events between 1941 and 2014. Simulation results showed that the restored floodplain significantly attenuates the upstream flood peak by up …
Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West
Optimizing Methods For Extraction Of Organic Compounds From Molluscan Shells, Kaydee Jo West
USF Tampa Graduate Theses and Dissertations
Mollusk shells contain proteins within and between the crystals of calcium carbonate. These organic molecules play an important role in biomineralization and shell function, and their stable isotope ratios of carbon and nitrogen are also thought to record important ecological information about the animal's diet and nutrient sources. These proteins can be preserved for millions of years, offering potential insight into pre-anthropogenic ecological conditions. However, shell organics in older shells are typically recovered in reduced abundances due to leaching and remaining organics are often converted from insoluble proteins to soluble, free amino acids, making them difficult to detect and recover. …
Modeling Of Soybean Under Present And Future Climates In Mozambique, Manuel António Dina Talacuece, Flávio Barbosa Justino, Rafael De Ávila Rodrigues, Milton Edgar Pereira Flores, Jéssica Garcia Nascimento, Eduardo Eduardo Santos
Modeling Of Soybean Under Present And Future Climates In Mozambique, Manuel António Dina Talacuece, Flávio Barbosa Justino, Rafael De Ávila Rodrigues, Milton Edgar Pereira Flores, Jéssica Garcia Nascimento, Eduardo Eduardo Santos
Daugherty Water for Food Global Institute: Faculty Publications
This study aims to calibrate and validate the generic crop model (CROPGRO-Soybean) and estimate the soybean yield, considering simulations with different sowing times for the current period (1990–2013) and future climate scenario (2014–2030). The database used came from observed data, nine climate models of CORDEX (Coordinated Regional climate Downscaling Experiment)-Africa framework and MERRA (Modern Era Retrospective-Analysis for Research and Applications) reanalysis. The calibration and validation data for the model were acquired in field experiments, carried out in the 2009/2010 and 2010/2011 growing seasons in the experimental area of the International Institute of Tropical Agriculture (IITA) in Angónia, Mozambique. The yield …
Development And Validation Of A Remote Sensing Model To Identify Anthropogenic Boreholes That Provide Dry Season, Refuge Habitat For Anopheles Vector Mosquitoes In Sub-Saharan Africa, James Pkemoi Kukat
USF Tampa Graduate Theses and Dissertations
A lack of surveillance systems is an impediment to public health intervention for perennial vector-borne disease transmission in northern tropical savanna region of Kenya. The population in this area are mostly poor nomadic pastoralists with little acquired functional immunity to Plasmodium falciparum, due to infrequent challenges with the parasite. A common characteristic in tropical savanna climatic zone is the availability of riverbeds that have anthropogenic boreholes that provide malaria vector mosquitoes, such as Anopheles gambiae s.l and Anopheles funestus, with aquatic refuge habitats for proliferation and endemic transmission to proximity human households during the dry-season. Unfortunately, currently there …
High-Resolution Surface Circulation Of The Bay Of Bengal Derived From Satellite Observation Data, Mridula Kuttyattu Rayaroth, Benny Neettumkara, Mohd Razali Mahmud
High-Resolution Surface Circulation Of The Bay Of Bengal Derived From Satellite Observation Data, Mridula Kuttyattu Rayaroth, Benny Neettumkara, Mohd Razali Mahmud
Journal of Marine Science and Technology–Taiwan
High-resolution surface circulation and its variability of the Bay of Bengal are derived by combining surface drifter and satellite observation data. The satellite altimetry data, satellitetracked surface drifter data and ocean surface winds from satellite scatterometers during 1993-2012 are used. The estimated velocities show good agreement with in-situ acoustic Doppler current profiler observations. The estimated velocity components are significantly correlated with monthly mean velocity components from Research Moored Array for AfricanAsian-Australian Monsoon Analysis and Prediction buoy data. The mean circulation exhibits the strong western boundary current, zonal currents and weak eastern boundary flow. Large spatial and temporal variations are found …
Slides: The Era Of River Anthropology: Social And Eco-Hydrological Science Connections And Capacity For Environmental Flows: Us Case Studies, Joseph E. Flotemersch, Lisa-Perras Gordon
Slides: The Era Of River Anthropology: Social And Eco-Hydrological Science Connections And Capacity For Environmental Flows: Us Case Studies, Joseph E. Flotemersch, Lisa-Perras Gordon
Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)
Presenter: Joe Flotemersch, US Environmental Protection Agency (EPA), Office of Research and Development
21 slides
Slides: The Columbia River Basin, Barbara Cosens
Slides: The Columbia River Basin, Barbara Cosens
Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)
Presenter: Barbara Cosens, Professor and Associate Dean of Faculty, University of Idaho College of Law, Waters of the West Interdisciplinary Program
16 slides
Agenda: Coping With Water Scarcity In River Basins Worldwide: Lessons Learned From Shared Experiences, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment
Agenda: Coping With Water Scarcity In River Basins Worldwide: Lessons Learned From Shared Experiences, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment
Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)
Water scarcity is increasingly dominating headlines throughout the world. In the southwestern USA, the looming water shortages on the Colorado River system and the unprecedented drought in California are garnering the greatest attention. Similar stories of scarcity and crisis can be found across the globe, suggesting an opportunity for sharing lessons and innovations. For example, the Colorado River and Australia's Murray-Darling Basin likely can share many lessons, as both systems were over-allocated, feature multiple jurisdictions, face similar climatic risks and drought stresses, and struggle to balance human demands with environmental needs. In this conference we cast our net broadly, exploring …
Slides: Rivers And People In The Neotropics: Social And Ecological Science For Environmental Flows, Elizabeth P. Anderson
Slides: Rivers And People In The Neotropics: Social And Ecological Science For Environmental Flows, Elizabeth P. Anderson
Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)
Presenter: Elizabeth P. Anderson, Florida International University
38 slides
Slides: Food For Thought: Water Requirements For Social-Ecological Systems, Michael Douglas, Sue Jackson
Slides: Food For Thought: Water Requirements For Social-Ecological Systems, Michael Douglas, Sue Jackson
Coping with Water Scarcity in River Basins Worldwide: Lessons Learned from Shared Experiences (Martz Summer Conference, June 9-10)
Presenters:
Michael Douglas, University of Western Australia, Charles Darwin University
Sue Jackson, Griffith University
35 slides
Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon
Pollutants And Foraminiferal Assemblages In Torrecillas Lagoon: An Environmental Micropaleontology Approach, Michael Martinez-Colon
USF Tampa Graduate Theses and Dissertations
Torrecillas Lagoon in the North Coast of Puerto Rico has experienced extensive anthropogenic influence over the past 400 years. Elevated concentrations of Potential Toxic Elements (PTEs) have been reported in surficial sediments. The main goal of this dissertation was to implement in Puerto Rico the use of benthic foraminifers as a bioindicators of PTEs and to compare the impact of Cu(II) on field samples with results of experimental work using cultures.
Analyses included geochemical assessment for bulk and carbonate- soluble bioavailable concentrations of PTEs in surface, core and pore-water samples, as well as analyses of grain-size, Percent Total Organic Carbon …
Shell Bluff – A Fossiliferous Ridge, The Site Of The Extinct Oyster Crassostrea Gigantissima And History Of Its Identification, Elliott O. Edwards Jr.
Shell Bluff – A Fossiliferous Ridge, The Site Of The Extinct Oyster Crassostrea Gigantissima And History Of Its Identification, Elliott O. Edwards Jr.
Georgia Journal of Science
Shell Bluff is described by geologists as stratigraphically one of the most important exposures in the Georgia Coastal Plain because the bluff is home to the large oyster, Crassostrea gigantissima, now extinct. Native Americans inhabited this area prior to Hernando DeSoto and his men who visited the area in 1540. They were probably the first Europeans to visit Shell Bluff. John and son William Bartram visited the bluff in 1764 and John described the bluff in his journal and the existence of large oysters. The British naturalist, John Finch, described a fossil oyster taken from the site in 1824 as …
Agenda: Indigenous Water Justice Symposium, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment
Agenda: Indigenous Water Justice Symposium, University Of Colorado Boulder. Getches-Wilkinson Center For Natural Resources, Energy, And The Environment
Indigenous Water Justice Symposium (June 6)
Indigenous peoples throughout the world face diverse and often formidable challenges of what might be termed “water justice.” On one hand, these challenges involve issues of distributional justice that concern Indigenous communities’ relative abilities to access and use water for self-determined purposes. On the other hand, issues of procedural justice are frequently associated with water allocation and management, encompassing fundamental matters like representation within governance entities and participation in decision-making processes. Yet another realm of water justice in which disputes are commonplace relates to the persistence of, and respect afforded to, Indigenous communities’ cultural traditions and values surrounding water—more specifically, …
The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson
The Growth And Ecology Of Upper Cambrian Microbialite Biostromes From The Notch Peak Formation In Utah, Ken P. Coulson
Loma Linda University Electronic Theses, Dissertations & Projects
Exposure of carbonate rocks within the uplifted mountains of southwestern Utah presents a unique opportunity to study the growth, morphology and ecology of two upper Cambrian microbialite reefs located within the Hellnmaria Member of the Notch Peak Formation. The first reef contains meter-length, strongly elongate microbialites that grew in a deep, subtidal marine environment. These elongate microbialites formed as a result of coalescence of round ‘algal’ heads, a process known to produce compound microbialite structures in shallow water, but seldom explored as a key factor in the elongation of deep, subtidal forms that grew in ancient environments. The second reef …
Taphonomy Of A Lance Formation(Maastrichtian, Wy) Dinosaur Bonebed With A Focus On Tooth Traces, Matthew A. Mclain
Taphonomy Of A Lance Formation(Maastrichtian, Wy) Dinosaur Bonebed With A Focus On Tooth Traces, Matthew A. Mclain
Loma Linda University Electronic Theses, Dissertations & Projects
The Rose Quarry bonebed found in the Maastrichtian Lance Formation of eastern Wyoming possesses a complex blendof taphonomic signatures. Disarticulated, disassociated, fragmented bones of various states of abrasion from dinosaurs, turtles, and crocodilians are clustered together in a channelized sandstone unit. The mismatched taphonomic signatures of the bonebed suggest that it is amixed assemblage, containing bones with different taphonomic histories that were washed together by a flood event. Sedimentological data,includingthe presence of large mud clasts in the bonebed,agree well with this hypothesis. The abundant breakage of the bones in the Rose Quarry bonebed is attributed mainly to trampling. This study …
Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy
Bathymetric Survey For Lakes Azuei And Enriquillo, Hispaniola, Michael Piasecki, Mahrokh Moknatian, Fred Moshary, Joseph Cleto, Yolanda Leon, Jorge Gonzalez, Daniel Comarazamy
Publications and Research
The two largest lakes on the Caribbean Island of Hispaniola, Lake Azuei in Haiti and Lake Enriquillo in the Dominican Republic, have experienced dramatic growth and surface area expansion over the past few years leading to severe flooding and loss of arable land around the lake perimeters. In order to better understand the reasons for this unprecedented rate of expansion and the resulting consequences a multi-disciplinary team comprised of researchers from Haiti, the DR, and the US have embarked on an extensive data collecting and hydrologic and climatological modeling campaign. While the sensor deployment entails stations that measure climatological data …
Sedimentology Of Kingston Peak Formation Kp1 Beds In Beck Canyon Region, Kingston Range, California, Dominic Joel Ombati
Sedimentology Of Kingston Peak Formation Kp1 Beds In Beck Canyon Region, Kingston Range, California, Dominic Joel Ombati
Loma Linda University Electronic Theses, Dissertations & Projects
The Neoproterozoic Kingston Peak Formation (KPF) is known for its diamictites interpreted as of glacial origin. The KPF overlies the Beck Spring Dolomite (BSD) that contains microfossils and microbialites. This study aims to test correlation between outcrops and understand the abrupt change from BSD to KPF. It focuses on the basal 4 meters of the KP1 subunit of the KPF as it appears in the Beck Canyon region, Kingston Range, California. We describe and correlate sedimentary rocks at and immediately overlying the contact and analyze the sedimentary structures, textures and sequences. We have found only three sites in the northern …
Coastal Ocean And Shelf-Sea Biogeochemical Cycling Of Trace Elements And Isotopes: Lessons Learned From Geotraces, Matthew A. Charette, Phoebe J. Lam, Maeve C. Lohan, Eun Young Kwon, Vanessa Hatje, Catherine Jeandel, Alan M. Shiller, Gregory A. Cutter, Alex Thomas, Philip W. Boyd
Coastal Ocean And Shelf-Sea Biogeochemical Cycling Of Trace Elements And Isotopes: Lessons Learned From Geotraces, Matthew A. Charette, Phoebe J. Lam, Maeve C. Lohan, Eun Young Kwon, Vanessa Hatje, Catherine Jeandel, Alan M. Shiller, Gregory A. Cutter, Alex Thomas, Philip W. Boyd
OES Faculty Publications
Continental shelves and shelf seas play a central role in the global carbon cycle. However, their importance with respect to trace element and isotope (TEI) inputs to ocean basins is less well understood. Here, we present major findings on shelf TEI biogeochemistry from the GEOTRACES programme as well as a proof of concept for a new method to estimate shelf TEI fluxes. The case studies focus on advances in our understanding of TEI cycling in the Arctic, transformations within a major river estuary (Amazon), shelf sediment micronutrient fluxes and basin-scale estimates of submarine groundwater discharge. The proposed shelf flux tracer …
In-Air Hearing Of A Diving Duck: A Comparison Of Psychoacoustic And Auditory Brainstem Response Thresholds, Sara E. Crowell, Alicia M. Wells-Berlin, Ronald E. Therrien, Sally E. Yannuzzi, Catherine E. Carr
In-Air Hearing Of A Diving Duck: A Comparison Of Psychoacoustic And Auditory Brainstem Response Thresholds, Sara E. Crowell, Alicia M. Wells-Berlin, Ronald E. Therrien, Sally E. Yannuzzi, Catherine E. Carr
United States Geological Survey: Staff Publications
Auditory sensitivity was measured in a species of diving duck that is not often kept in captivity, the lesser scaup. Behavioral (psychoacoustics) and electrophysiological [the auditory brainstem response (ABR)] methods were used to measure in-air auditory sensitivity, and the resulting audiograms were compared. Both approaches yielded audiograms with similar U-shapes and regions of greatest sensitivity (2000-3000 Hz). However, ABR thresholds were higher than psychoacoustic thresholds at all frequencies. This difference was least at the highest frequency tested using both methods (5700 Hz) and greatest at 1000 Hz, where the ABR threshold was 26.8 dB higher than the behavioral measure of …
Dissolved Organic Carbon Fluxes From A New England Salt Marsh, Hayley Nicole Schiebel
Dissolved Organic Carbon Fluxes From A New England Salt Marsh, Hayley Nicole Schiebel
Graduate Doctoral Dissertations
Blue carbon systems (mangroves, salt marshes, and seagrass beds) sequester large amounts of carbon via primary productivity and sedimentation. Sequestered carbon can be respired back to the atmosphere, buried for long time periods, or exported (“outwelled”) to adjacent ecosystems. This study estimates the total outwelling of dissolved organic carbon (DOC) from the Neponset Salt Marsh (Boston, Massachusetts) as well as the major plant and sediment processes contributing to the overall flux. The total export was quantified via high-resolution in situ chromophoric dissolved organic matter (CDOM) measurements as a proxy for DOC using 12 years of transect data. Seasonal trends, alternate …
Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres
Cone In Cone Concretions Of The Stanley Group In Southeastern Oklahoma, Kyle B. Ayres
Electronic Theses and Dissertations
Cone in cone concretions found in the Stanley Group of Southeastern Oklahoma have a variety of external and internal attributes which allow diagenetic and theoretical models of formation to be hypothesized. Stanley Group carbonate cone in cone concretions are initially formed in sulfur reducing horizons at shallow burial depths in a poorly circulated possibly deep trough containing siliceous sediments and organic matter. Collected concretions near the town of Smithville, Oklahoma displayed four different external morphologies and four variations of mineral constituents. All concretions contained microscopic cones which initiated diffusion and/or fluid patterns and is an early cementation process that directly …
Characterization Of Lower Permian Carbonate Subaqueous Gravity Flows In Crockett County, Texas, Wesley L. Turner
Characterization Of Lower Permian Carbonate Subaqueous Gravity Flows In Crockett County, Texas, Wesley L. Turner
Electronic Theses and Dissertations
Transitional sediments on carbonate ramp slopes act as a link to relatively well-studied platform and basin depositional environments. In the southern Midland Basin, the key to understanding the relationship between these environments lies in the allochthonous gravity flow sediments found on the slope. Here, a succession of various gravity flow deposits is used to interpret how base level fluctuations affect the type of deposits found on the slope and their effect on the deep basinal environment. This study utilizes core samples from the Wolfcamp Formation adjacent to the Central Basin Platform in five wells in Northwest Crockett County, Texas. The …
An Analysis Of The Physical And Cultural Landscape Of Grand Isle, Louisiana, Alexis Thomas
An Analysis Of The Physical And Cultural Landscape Of Grand Isle, Louisiana, Alexis Thomas
LSU New Orleans Theses and Dissertations
The town of Grand Isle, Louisiana, and its rich geographic history, can offer insight into the early history of the State of Louisiana and the establishment of the United States as a country, as well as the study of the formation of barrier islands and methods of land use with such areas. The following thesis presents a geographic, as well as a historical, analysis of Grand Isle’s history. It attempts to answer the following questions: What is the shape, form, and origin of the physical landscape of Grand Isle? How have humans interacted with the land and surrounding areas of …
The First Hominin From The Early Pleistocene Paleocave Of Haasgat, South Africa, Ab Leece, Anthony D T Kegley, Rodrigo S. Lacruz, Andy I R Herries, Jason Hemingway, Lazarus Kgasi, Stephany Potze, Justin W. Adams
The First Hominin From The Early Pleistocene Paleocave Of Haasgat, South Africa, Ab Leece, Anthony D T Kegley, Rodrigo S. Lacruz, Andy I R Herries, Jason Hemingway, Lazarus Kgasi, Stephany Potze, Justin W. Adams
Peer Reviewed Articles
Haasgat is a primate-rich fossil locality in the northeastern part of the Fossil Hominid Sites of South Africa UNESCO World Heritage Site. Here we report the first hominin identified from Haasgat, a partial maxillary molar (HGT 500), that was recovered from an ex situ calcified sediment block sampled from the locality. The in situ fossil bearing deposits of the Haasgat paleokarstic deposits are estimated to date to slightly older than 1.95 Ma based on magnetobiostratigraphy. This places the hominin specimen at a critical time period in South Africa that marks the last occurrence of Australopithecus around 1.98 Ma and the …
Age Re-Assessment Of The Cave Bear Assemblage From Urşilor Cave, North-Western Romania, Marius V. Robu
Age Re-Assessment Of The Cave Bear Assemblage From Urşilor Cave, North-Western Romania, Marius V. Robu
International Journal of Speleology
The most common methods used for assessing the relative age of a cave bear bone assemblage are the P4/4 index (morphodynamic index of the cave bear fourth premolar), the K-index and the Index of Plumpness (both used for cave bear’s 2nd metatarsal). Preliminary work on this (Robu et al., 2011), for Urşilor Cave (NW Romania), has indicated one of the youngest European cave bear populations. As the number of extracted fossil bones from the palaeontological excavation increased recently, a re-assessment of the of the age of the cave bear assemblage is necessary. 206 cave bear fourth …