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Seasonal Changes In The Sinking Particulate Flux And In The Nitrogen Cycle Within The Euphotic And Twilight Zones Of The Cariaco Basin, Venezuela, Enrique Montes-Herrera

USF Tampa Graduate Theses and Dissertations

This study explored the effects of seasonal variability on the geochemistry of sinking pthesiss and on the nitrogen cycle of the Cariaco Basin. Pthesis fluxes were measured at the base of the euphotic zone (the depth of 1% of photosynthetically active radiation - PAR) with drifting sediment traps during months of upwelling and non-upwelling regimes from March 2007 to November 2009. Flux estimates were analyzed in the context of seasonal variations in sea surface temperature, primary productivity, and chlorophyll a concentrations using data generated by the CARIACO Time-series Program as well as satellite data. Additionally, nine years (1996-2000 and 2004-2007) …

Collaboration And Climate Action At The Local Scale, Linda Lyshall

Antioch University Dissertations & Theses

This dissertation encompasses a case study and a Participatory Action Research project. The case study focuses on climate change mitigation activities within King County, Washington and its 39 cities and towns and discusses progress and challenges related to transportation issues, efficiency measures, and sustainability planning. The findings indicate there is a high level of activity in waste reduction, environmental outreach and education, bicycle and pedestrian promotion, tree canopy protection, sustainability policies, and green building. Other categories, such as energy efficiency, electric vehicle infrastructure, and greenhouse gas emission inventories and goal setting are on the rise. Twelve of the cities were …

Depositional And Stratigraphic Significance Of Marine, Green-Clay, Mineral Facies In The Lower-Middle Mississippian Borden And Fort Payne Formations, Western Appalachian And Eastern Illinois Basins, Kentucky, Devi Bhagabati Prasad Udgata

University of Kentucky Doctoral Dissertations

Detailed study of strata associated with the glauconite-rich Floyds Knob Bed in the western Appalachian and eastern Illinois basins have corroborated previous interpretations that the unit is a widespread, largely synchronous marker horizon. However, in some areas there are multiple glauconite beds; in others a distinct bed is lacking, but the glauconite is dispersed throughout many beds, forming an interval rather than a distinct bed. In Kentucky and adjacent states, the Floyds Knob interval, in upper parts of the Lower-Middle Mississippian Borden-Grainger delta sequence and in lower parts of the Fort Payne carbonate sequence, was deposited at the end of …

Petrologic, Geochemical, And Geochronologic Constraints On The Tectonic Evolution Of The Southern Appalachian Orogen, Blue Ridge Province Of Western North Carolina, Eric Douglas Anderson

University of Kentucky Doctoral Dissertations

The Blue Ridge Province of western North Carolina contains a wide variety of metamorphosed igneous and sedimentary rocks that record the tectonic effects of Precambrian and Paleozoic orogenic cycles. Tectonic interpretations of the events that led to the present configuration are varied and often conflicting. This investigation examines metamorphosed mafic rocks that are widely interpreted to have formed during the closure of ocean basins. Metabasites, and specifically eclogites, have a tendency to mark tectonic sutures and frequently preserve pressure (P), temperature (T), and age data (t) that can be gleaned from mineral equilibria and U-Pb isotopic compositions. As such, the …

Stratigraphy And Petroleum Production Potential Of The Spearfish Formation In North Central North Dakota, Nnaemeka C. Anyanwu

Theses and Dissertations

The Spearfish oil play is unconventional requiring the use of horizontal wells that are fracture stimulated to deliver economic flow rates. However, fraccing into the underlying water has been a source of significant production problems for operators. The key to developing the area is to keep the individual fracs large enough to stimulate the tight Spearfish sands but not to let them propagate into the underlying water zone.

The Spearfish Formation of the Black Hills has been traced into the subsurface of the Williston Basin in western North Dakota from bore holes at the northern margin of the outcrop area …

Identifying Potential Geothermal Resources From Co-Produced Fluids Using Existing Data From Drilling Logs : Williston, North Dakota, Anna M. Crowell

Theses and Dissertations

With the current need for technology that will allow for environmentally-friendly power generation, geothermal power has become an attractive resource given its low environmental impact and potential cost savings. One specific resource is co-produced water from oil wells that are not currently producing, but can yield formation waters that are both high enough in temperature and fluid volume to operate the turbines of binary geothermal power systems. The data required to identify sites, i.e. bottom-hole temperatures (BHT), latitude, longitude, total depth of hole (TD) in meters, the identification number, and the amount of water produced in gallons, can be mined …

Early Season Depletion Of Dissolved Iron In The Ross Sea Polynya: Implications For Iron Dynamics On The Antarctic Continental Shelf, Peter N. Sedwick, C. M. Marsay, B. M. Sohst, A. M. Aguilar-Islas, M. C. Lohan, M. C. Long, K. R. Arrigo, R. B. Dunbar, M. A. Saito, W. O. Smith, G. R. Ditullio

OES Faculty Publications

The Ross Sea polynya is among the most productive regions in the Southern Ocean and may constitute a significant oceanic CO₂sink. Based on results from several field studies, this region has been considered seasonally iron limited, whereby a "winter reserve" of dissolved iron (dFe) is progressively depleted during the growing season to low concentrations (~ 0.1 nM) that limit phytoplankton growth in the austral summer (December-February). Here we report new iron data for the Ross Sea polynya during austral summer 2005-2006 (27 December-22 January) and the following austral spring 2006 (16 November-3 December). The summer 2005-2006 data show …

Evidence From The Florida Straits For Younger Dryas Ocean Circulation Changes, Jean Lynch-Stieglitz, Matthew W. Schmidt, William B. Curry

OES Faculty Publications

The waters passing through the Florida Straits today reflect both the western portion of the wind-driven subtropical gyre and the northward flow of the upper waters which cross the equator, compensating North Atlantic Deep Water export as part of the large-scale Atlantic meridional overturning circulation. It has been postulated from various lines of evidence that the overturning circulation was weaker during the Younger Dryas cold event of the last deglaciation. We show here that the contrast in the oxygen isotopic composition of benthic foraminiferal tests across the Florida Current is reduced during the Younger Dryas. This most likely reflects a …

Florida Straits Deglacial Temperature And Salinity Change: Implications For Tropical Hydrologic Cycle Variability During The Younger Dryas, Matthew W. Schmidt, Jean Lynch-Stieglitz

OES Faculty Publications

The prevailing paradigm of abrupt climate change holds that rapid shifts associated with the most extreme climate swings of the last glacial cycle were forced by changes in the strength and northward extension of Atlantic Meridional Overturning Circulation (AMOC), resulting in an abrupt reorganization of atmospheric circulation patterns with global teleconnections. To determine the timing of tropical Atlantic atmospheric circulation changes over the past 21 ka BP, we reconstruct high resolution sea surface temperature and δ¹⁸O_SW (a proxy for surface salinity) records based on Mg/Ca ratios and oxygen isotope measurements in the planktonic foraminifera Globigerinoides ruber from …

Meridional Shifts In The Marine Itcz And The Tropical Hydrologic Cycle Over The Last Three Glacial Cycles, Matthew W. Schmidt, Howard J. Spero

OES Faculty Publications

Paleoproxy studies show a strong correlation between tropical climate and high-latitude temperature variability recorded in the Greenland ice cores over the last glacial cycle. In particular, abrupt cooling events in the Greenland Ice Sheet Project II δ¹⁸O ice record appear synchronous with a southward migration of the Intertropical Convergence Zone (ITCZ) in the Atlantic, a weakening of the Indian and East Asian monsoon systems, and a strengthening of the South American monsoon system. Because this high-to-low-latitude climate teleconnection significantly alters the tropical hydrologic cycle around the globe, it plays a critical role in regulating global climate on glacial-interglacial …

Lithospheric Control On The Spatial Pattern Of Azores Hotspot Seafloor Anomalies: Constraints From A Model Of Plume-Triple Junction Interaction, Jennifer E. Georgen

OES Faculty Publications

The Azores hotspot is located near a plate boundary triple junction (TJ) consisting of the Terceira Rift (TER) and two branches of the Mid-Atlantic Ridge (MAR). The seafloor expression of the Azores hotspot has a complex spatial pattern. Latitudinal anomalies in seafloor depth and other data along the MAR extend farther to the south of the inferred location of the mantle heterogeneity than to the north. Longitudinal anomalies span a greater distance to the east of the MAR (along the TER) than to the west. A finite element model is used to investigate how the divergence of three plates away …

Modern Dirty Sea Ice Characteristics And Sources: The Role Of Anchor Ice, Dennis A. Darby, Wesley B. Myers, Martin Jakobsson, Ignatius Rigor

OES Faculty Publications

Extensive dirty ice patches with up to 7 kg m^-2 sediment concentrations in layers of up to 10 cm thickness were encountered in 2005 and 2007 in numerous areas across the central Arctic. The Fe grain fingerprint determination of sources for these sampled dirty ice floes indicated both Russian and Canadian sources, with the latter dominating. The presence of benthic shells and sea weeds along with thick layers (2-10 cm) of sediment covering 5-10 m² indicates an anchor ice entrainment origin as opposed to suspension freezing for some of these floes. The anchor ice origin might explain the …

Using Temperature Profiles To Investigate The Hyporheic Zone In An Agricultural Drainage Ditch, Richard A. Suggs

Theses and Dissertations

During the last three decades, there has been much research on ground water/surface water interaction and hyporheic zone processes in natural rivers and streams. Research into natural systems has revealed significant ground water/surface water interaction and a complex variability that depends primarily on surface conditions, subsurface composition, and seasonal influences. Hyporheic zone interaction is an important factor contributing to water quality of both surface water and ground water systems.

This research expands on the concept of using heat transport, as revealed by temperature variation, as an analogue for water movement within a surface water/ground water system to include the man-made …

Geomechanical Stability Analysis For Co2 Sequestration In Carbonate Formation, Xue J. Zhou

Theses and Dissertations

Geomechanical analysis is one of the fundamental pillars to build up the confidence of geological sequestration of CO2. Large scale CO2 sequestration in deep carbonate formation is a complicated geological process, which will non-reversibly transform the presumed equivalent and stable status of a sedimentary basin that formed over millions of years: chemically, hydraulically, geothermally, and geomechanically. In this dissertation, thermoporoelasticity guides the theoretical establishment of a conservative baseline for the geomechanical stability analysis of CO2 sequestration.

Extensive laboratory tests, including CO2 flooding tests, permeability tests, uniaxial and triaxial tests, Brazilian tensile strength tests, poroelasticity tests, point load tests, and fracture …

Yellow-Fluorescing Calcite From Sterling Hill, James A. Van Fleet, E. R. Verbeek

Faculty Journal Articles

No abstract provided.

Eogenetic Caves In Conglomerate: An Example From Udin Boršt, Slovenia, Matej Lipar, Mateja Ferk

International Journal of Speleology

Udin Boršt is a karstified terrace of carbonate rock, which is of fluvioglacial origin, and is situated in the north-western part of Slovenia. There are 15 registered caves, which have been interpreted as caves in conglomerate, while karst of Udin Boršt itself was interpreted as conglomerate karst, shallow karst or isolated karst. In this article, caves in Udin Boršt have been interpreted as eogenetic caves. Based on porosity and bedding material, different types of caves and cave passages have developed. Four general types of eogenetic caves found in Udin Boršt are; linear stream caves, shelter caves, breakdown caves and vadose …

A New Foodweb Based On Microbes In Calcitic Caves: The Cansiliella (Beetles) Case In Northern Italy, Maurizio G. Paoletti, Mattia Beggio, Angelo Leandro Dreon, Alberto Pamio, Tiziano Gomiero, Mauro Brilli, Luca Dorigo, Giuseppe Concheri, Andrea Squartini, Annette Summers Engel

International Journal of Speleology

The troglobitic beetle, Cansiliella servadeii percolating water on moonmilk, a speleothem formation in Grotta della Foos, Italy. Results from analyses of stable isotopes of carbon and nitrogen suggest that acquires and assimilates dissolved allochthonous organic carbon, inorganic nitrogen, and possibly phosphorus and other nutrients from the microbial fauna associated with moonmilk.

Minerogenetic Mechanisms Occurring In The Cave Environment: An Overview, Bogdan P. Onac, Paolo Forti

International Journal of Speleology

Perhaps man’s first motivation to explore caves, beyond using them as shelter, was the search for substances that were not available elsewhere: most of them were minerals. However, for a long time it was believed that the cave environment was not very interesting from the mineralogical point of view. This was due to the fact that most cave deposits are normally composed of a single compound: calcium carbonate. Therefore, the systematic study of cave mineralogy is of only recent origin. However, although only a limited number of natural cavities have been investigated in detail, about 350 cave minerals have already …

Black Mn-Fe Crusts As Markers Of Abrupt Palaeoenvironmental Changes In El Soplao Cave (Cantabria, Spain), Fernando Gázquez, Jose Maria Calaforra, Paolo Forti

International Journal of Speleology

Peculiar iron and manganese deposits coating walls, floors and ceilings of many galleries are one of the special features of the El Soplao Cave (Cantabria, Spain). These speleothems appear to have been deposited over wall clay deposits, as well as forming part of flowstones. Structure of crusts is essentially amorphous but several manganese and iron oxides were identified like goethite and birnessite, though all occur with a low degree of crystallinity. In the outer layer of the crusts, alteration iron minerals appear that derive from previous minerals in a process probably mediated by microorganisms. EDX microanalyses report fairly high values …

Mineralogy Of Iza Cave (Rodnei Mountains, N. Romania), Tudor Tămaş, Ferenc Kristály, Lucian Barbu-Tudoran

International Journal of Speleology

The secondary minerals from Iza Cave result from the interactions of karst water and/or cave atmosphere over a variety of sedimentary and metamorphic rocks. The cave passages expose at various extents Eocene limestones and conglomerates, Oligocene black shales, Upper Precambrian micaschists, marble and dolomitic marble and associated ore deposits.

Twelve secondary minerals identified in the cave (carbonates, sulfates, phosphates, oxides and hydroxides, and silicates) are presented in this study. Calcite, aragonite, gypsum, brushite and hydroxylapatite are the components of common speleothems in the limestone, dolomite and conglomerate areas of the cave. Ankerite crusts are related to areas with pyrite mineralization …

A Comparative Integrated Geophysical Study Of Horseshoe Chimney Cave, Colorado Bend State Park, Texas, Wesley A. Brown, Kevin W. Stafford, Mindy Shaw-Faulkner, Andy Grubbs

International Journal of Speleology

An integrated geophysical study was performed over a known cave in Colorado Bend State Park (CBSP), Texas, where shallow karst features are common within the Ellenberger Limestone. Geophysical survey such as microgravity, ground penetrating radar (GPR), direct current (DC) resistivity, capacitively coupled (CC) resistivity, induced polarization (IP) and ground conductivity (GC) measurements were performed in an effort to distinguish which geophysical method worked most effectively and efficiently in detecting the presence of subsurface voids, caves and collapsed features. Horseshoe Chimney Cave (HCC), which is part of a larger network of cave systems, provides a good control environment for this research. …

Evolution Of The Veternica Cave (Medvednica Mountain, Croatia) Drainage System: Insights From The Distribution And Dating Of Cave Deposits, Damir Lacković, Bosiljka Glumac, Yemane Asmerom, Andrej Stroj

Geosciences: Faculty Publications

Detailed field examination, U-Th age dating, and stable isotope analysis of Veternica flowstone and shelfstone deposits have been employed in order to unravel details about the geological history of Veternica Cave (Medvednica Mountain, Croatia). The study was carried out in the hydrologically inactive part of the main cave channel, which is developed mainly along the unconformity between Triassic dolostone and Miocene limestone. For 180 m from the cave entrance, (located at 320 metres above sea level (asl)), the morphology of the main channel reflects exclusively phreatic conditions in the cave until the end of its hydrological activity. From 180 to …

Evaluating Spawning Migration Patterns And Predicting Spawning Success Of Shovelnose Sturgeon In The Lower Missouri River, M. L. Wildhaber, S. H. Holan, G. M. Davis, D. W. Gladish, A. J. Delonay, Diana M. Papoulias, D. K. Sommerhauser

United States Geological Survey: Staff Publications

Approaches using telemetry, precise reproductive assessments, and surgically implanted data storage tags (DSTs) were used in combination with novel applications of analytical techniques for fish movement studies to describe patterns in migratory behavior and predict spawning success of gravid shovelnose sturgeon. From 2004 to 2007, over 300 gravid female shovelnose sturgeon (Scaphirhynchus platorynchus) from the Lower Missouri River, that were expected to spawn in the year they were collected, were surgically implanted with transmitters and archival DSTs. Functional cluster modeling of telemetry data from the spawning season suggested two common migration patterns of gravid female shovelnose sturgeon. Fish …

Land Change Variability And Human–Environment Dynamics In The United States Great Plains, Mark A, Drummond, Roger F. Auch, Krista A. Karstensen, Kristi L. Sayler, Janis L. Taylor, Thomas Loveland

United States Geological Survey: Staff Publications

Land use and land cover changes have complex linkages to climate variability and change, biophysical resources, and socioeconomic driving forces. To assess these land change dynamics and their causes in the Great Plains, we compare and contrast contemporary changes across 16 ecoregions using Landsat satellite data and statistical analysis. Large-area change analysis of agricultural regions is often hampered by change detection error and the tendency for land conversions to occur at the local-scale. To facilitate a regional-scale analysis, a statistical sampling design of randomly selected 10 km × 10 km blocks is used to efficiently identify the types and rates …

Introduction To “Environmental Contaminants In Biota, 2nd Edition”, W. Nelson Beyer, James P. Meador

United States Geological Survey: Staff Publications

Ecotoxicology is the study of the movement of environmental contaminants through ecosystems and their effects on plants and animals. Examining tissue residues of these contaminants in biota is basic to ecotoxicology, both for understanding the movement of contaminants within organisms and through food chains, and for understanding and quantifying injuries to organisms and their communities. This book provides guidance on interpreting tissue concentrations of environmental contaminants.

Tissue concentrations have long been used both to identify the cause of toxicity in animals and as a measure of the severity of toxicity. More recently, they have been incorporated into environmental models, tying …

Spatial Patch Occupancy Patterns Of The Lower Keys Marsh Rabbit, Mitchell J. Eaton, Phillip T. Hughes, James D. Nichols, Anne Morkill, Chad Anderson

United States Geological Survey: Staff Publications

Reliable estimates of presence or absence of a species can provide substantial information on management questions related to distribution and habitat use but should incorporate the probability of detection to reduce bias. We surveyed for the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) in habitat patches on 5 Florida Key islands, USA, to estimate occupancy and detection probabilities. We derived detection probabilities using spatial replication of plots and evaluated hypotheses that patch location (coastal or interior) and patch size influence occupancy and detection. Results demonstrate that detection probability, given rabbits were present, was <0.5 and suggest that naı¨ve estimates (i.e., estimates without consideration of imperfect detection) of patch occupancy are negatively biased. We found that patch size and location influenced probability of occupancy but not detection. Our findings will be used by Refuge managers to evaluate population trends of Lower Keys marsh rabbits from historical data and to guide management decisions for species recovery. The sampling and analytical methods we used may be useful for researchers and managers of other endangered lagomorphs and cryptic or fossorial animals occupying diverse habitats.

Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link

United States Geological Survey: Staff Publications

Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models …

Adaptive Resource Management And The Value Of Information, Byron K. Williams, Mitchell J. Eaton, David R. Breininger

United States Geological Survey: Staff Publications

The value of information is a general and broadly applicable concept that has been used for several decades to aid in making decisions in the face of uncertainty. Yet there are relatively few examples of its use in ecology and natural resources management, and almost none that are framed in terms of the future impacts of management decisions. In this paper we discuss the value of information in a context of adaptive management, in which actions are taken sequentially over a time frame and both future resource conditions and residual uncertainties about resource responses are taken into account. Our objective …

Estimating Age From Recapture Data: Integrating Incremental Growth Measures With Ancillary Data To Infer Age-At-Length, Mitchell J. Eaton, William A. Link

United States Geological Survey: Staff Publications

Estimating the age of individuals in wild populations can be of fundamental importance for answering ecological questions, modeling population demographics, and managing exploited or threatened species. Significant effort has been devoted to determining age through the use of growth annuli, secondary physical characteristics related to age, and growth models. Many species, however, either do not exhibit physical characteristics useful for independent age validation or are too rare to justify sacrificing a large number of individuals to establish the relationship between size and age. Length-at-age models are well represented in the fisheries and other wildlife management literature. Many of these models …

Spatial Patch Occupancy Patterns Of The Lower Keys Marsh Rabbit, Mitchell J. Eaton, Phillip T. Hughes, James D. Nichols, Anne Morkill, Chad Anderson

United States Geological Survey: Staff Publications

Reliable estimates of presence or absence of a species can provide substantial information on management questions related to distribution and habitat use but should incorporate the probability of detection to reduce bias. We surveyed for the endangered Lower Keys marsh rabbit (Sylvilagus palustris hefneri) in habitat patches on 5 Florida Key islands, USA, to estimate occupancy and detection probabilities. We derived detection probabilities using spatial replication of plots and evaluated hypotheses that patch location (coastal or interior) and patch size influence occupancy and detection. Results demonstrate that detection probability, given rabbits were present, was <0.5 and suggest that naı¨ve estimates (i.e., estimates without consideration of imperfect detection) of patch occupancy are negatively biased. We found that patch size and location influenced probability of occupancy but not detection. Our findings will be used by Refuge managers to evaluate population trends of Lower Keys marsh rabbits from historical data and to guide management decisions for species recovery. The sampling and analytical methods we used may be useful for researchers and managers of other endangered lagomorphs and cryptic or fossorial animals occupying diverse habitats.