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Studies On Benthic Denitrification In The Chwaka Bay Mangrove Sediments, Zanzibar, Sm Mahommed, Rw Johnstone

Tanzania Journal of Science

Denitrification was measured at three sites in a narrow tidal creek in the Chwaka mangrove ecosystem. Denitrification arising from water column nitrate (Dw) was low (< 0.1μM Nm-2h-1) and there was little spatial and seasonal variation in Dw rates in the creek. Coupled nitrification-denitrification (Dn) was found to be low, but within the range measured in other mangrove sediments. Average values ranged from 0.01 to 0.45 μM Nm-2h-1 and showed strong spatial variations. The low denitrifcation rates observed in the creek were possibly as a result of the low availability of NO3 and high C:N values of the organic matter in the sediment. Spatial variations in denitrification rates were due to variations in concentration levels of organic matter and possibly to disproportionate competition for inorganic nitrogen between denitrifiers and benthic autotrophs among sites. There were no seasonal differences in denitrification rates. Results from the present study suggest that sediment denitrification does not play a major role as a sink for N in this ecosystem

A 700-Year Record Of Atmospheric Circulation Developed From The Law Dome Ice Core, East Antarctica, Joseph M. Souney Jr, Paul A. Mayewski, Ian D. Goodwin, David Meeker, Vin Morgan, Mark Aj Curran, Tas D. Van Ommen, Anne S. Palmer

All Materials

A 700-year, high-resolution, multivariate ice core record from Dome Summit South (DSS) (66°46′S, 112°48′E; 1370 m), Law Dome, is used to investigate sea level pressure (SLP) variability in the region of East Antarctica. Empirical orthogonal function (EOF) analysis reveals that the first EOF (LDEOF1) of the combined glaciochemical, oxygen isotope ratio, and accumulation rate record from DSS represents most of the variability in sea salt seen in the record. LDEOF1 is positively correlated (at least 95% confidence level) to instrumental June mean SLP across most of East Antarctica. Over the last 700 years, LDEOF1 levels at Law Dome were the …

Enhancement Of Wind-Driven Upwelling And Downwelling By Alongshore Bathymetric Variability, James M. Pringle

Earth Sciences

Steady wind-driven flow along a shelf of changing width is described with a frictional barotropic model valid in the limit of small Rossby and Burger number. In these limits, an alongshore wind drives enhanced onshelf transport in a coastal ocean if the shelf widens downwind, and the change in shelf width only affects the flow in the direction of Kelvin wave propagation ("downwave'') from the change in shelf width. There is enhanced onshore transport of cold, nutrient-laden bottom water if the winds favor upwelling and the shelf narrows in the direction of Kelvin wave propagation. This enhanced transport extends a …

Soils Of Mississippi County, Arkansas, J. M. Mckimmey, B. Dixon, H. D. Scott, C. M. Scarlat

AAES Research Reports and Research Bulletins

Along with air and water, soil contributes essential processes to the natural order of global cycles. With the exception of edibles from the sea, virtually everything we, and most other land-based animals, eat is derived from soil. Soil is a storage medium of essential minerals and nutrients for fulfilling our agricultural and nutritional needs. Humans work the soil to provide the basics of food, clothing, and shelter. We also use the soil as a medium to store and discard our waste. Virtually everything we do is in some way connected to soil

Early Deglaciation In The Tropical Andes, G. O. Seltzer, D. T. Rodbell, P. A. Baker, Sherilyn C. Fritz, P. M. Tapia, H. D. Rowe, R. B. Dunbar, Peter U. Clark

Department of Earth and Atmospheric Sciences: Faculty Publications

Analysis of sediment records from lakes located beyond the glacial limit in the Andes has provided, for the first time, an independent assessment of effective moisture ( precipitation minus evaporation) and the timing of the last glaciation (1). Conditions were wet at the LGM and remained so until approximately 15,000 cal yr B.P. (2). However, deglaciation was under way from the LGM between 22,000 and 19,500 cal yr B.P., which reinforces the observation that deglaciation in the tropical Andes was primarily forced by an increase in mean annual temperature during a wet postglacial interval (3, 4).

Ua66/8/3 Geogram, Wku Geography & Geology

WKU Administration Documents

Newsletter created by and about the WKU Geography & Geology highlighting activities of faculty, students and alumni.

Earth News, V26, Fall 2002, Department Of Earth Science, University Of Northern Iowa.

Earth News

Inside this issue:

--- Earth Science Staff Activities
--- STORM Curriculum Development Update
--- Earth Science Majors
--- Earth Science Student Assistants
--- Earth Science Seminar Series
--- Sigma Gamma Epsilon - Gamma Sigma Chapter
--- Summer 2002 Field Course "Paleontology in the Canadian Rockies"
--- Studies in the Geology of Iowa for Teachers
--- Workshop Teaches Educators the Value of Aggregates
--- Quarry Open House is a Smash Hit
--- 2002 Earth Science Graduates
--- Student Internships
--- Student Research Presentations
--- Gifts to the Department of Earth Science
--- 2002-2003 Scholarship and Award Recipients
--- President Bush Meets …

Phillips Brook Catchment Appraisal, Paul D. Galloway

Resource management technical reports

This report describes the soils, hydrology and natural vegetation of the Phillips Brook catchment near Toodyay, Western Australia and provides information on the threats to agriculture, infrastructure and natural resources from salinity, waterlogging, erosion and other land degradation processes.

Development And Implementation Of A Comprehensive Lake And Reservoir Strategy For Nebraska As A Model For Agricultural Dominated Ecosystems, John C. Holz, James W. Merchant, Anatoly A. Gitelson, Sherilyn C. Fritz, Kyle D. Hoagland, Istvan Bogardi, Donald C. Rundquist

Department of Earth and Atmospheric Sciences: Faculty Publications

In agriculturally dominated regions, land use practices have an unusually large impact on water bodies and, therefore, land use may reduce the utility of current ecoregion-based approaches to lake classification by dampening the signals that underlie the ecoregion framework. A team of water quality researchers has been assembled to develop a comprehensive classification scheme for agriculturally dominated ecosystems, using Nebraska as a highly representative model. Three objectives critical to achieving this goal are to establish: (1) a protocol for aggregating water bodies in agricultural ecosystems into classification strata and identifying reference conditions for these classes; (2) the role of remote …

Preliminary Geochemical Evaluation Of Groundwaters From Wells Of The Nye County Early Warning Drilling Program, Irene Farnham, Klaus J. Stetzenbach, Amy J. Smiecinski

Publications (YM)

As part of the Yucca Mountain Oversight program, the Nye County Nuclear Waste Repository Project Office (NWRPO) has established a groundwater monitoring program to protect groundwater resources for the residents of Nye County in Amargosa and Pahrump Valleys. This groundwater monitoring program, referred to as the Nye County Early Warning Drilling Program (NCEWDP), involves drilling a series of wells down-gradient from Yucca Mountain for long term groundwater monitoring and also to provide much needed geologic and hydrologic information in this area. A comprehensive database of aquifer parameters in the alluvial, volcanic, and carbonate aquifers down-gradient hydrogeologically of Yucca Mountain is …

Using The Index Of Biotic Integrity Of Fish Communities To Evaluate Habitat Quality In Middle Chattahoochee River Tributaries, Theodor W. Roever

Theses and Dissertations

An ichthyological survey was conducted within the lower Piedmont and upper Coastal Plain physiographic regions of the middle Chattahoochee River drainage basin between August 1998 and September 2000. Sampling was conducted by Columbus State University (CSU) under contract to Columbus Water Works for the purpose of obtaining biological measurements of watershed health. Objectives of the survey were the establishment of a data baseline of IBI scores for this ecoregion and to ascertain if there was a correlation between the IBI score and human influence. The thesis to be tested is: 'Fish community IBI scores of different watersheds within the Middle …

A Regional Gis-Based Analysis Of Elk Habitat Suitability In Northeast Nebraska, J W. Fisher

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

No abstract provided.

Influence Of Light And Nutrients On Atrazine Toxicity To Freshwater Algae, Crystal J. Hansen

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

No abstract provided.

Availability Of Organochlorides And Accumulation In Populations Of Tadarida Brasiliensis (Free-Tailed Bat) And Eptesicus Fuscus (Big Brown Bat), Michelle Lee Smith

Theses and Dissertations

Organochlorides were historically effective in controlling a wide range of pests. However, organochlorides have proved to present many problems to the health and welfare of other organisms. Due to these problems, especially declines in wildlife populations, organochlorides were restricted in the 1970's and a majority of them were banned in the mid to late 1980's. The effects of organochlorides on bats such as Tadarida brasiliensis and Eptesicus fuscus have been intensively studied. The effects can range from problems with reproduction to mortality. My analysis of populations of T. brasiliensis and E. fuscus showed that organochlorides are still present in the …

Genesis And Morphology Of Soil Pendants In Quaternary Landforms Of Pahranagat Valley, Nevada, Amy Lynn Brock

UNLV Theses, Dissertations, Professional Papers, and Capstones

Five geomorphic surfaces present in the northern Pahranagat Valley, Lincoln County, Nevada range in age from Early Pleistocene to Recent (Q1-Q5) and vary in clast lithology from dolomite to volcanic tephras. Two chronosequences and 5 lithosequences were compared to evaluate micro and macromorphic characteristics and development of soil pendants. This study presents a new interpretation for soil pendant development. Key features observed in the Pahranagat Valley pendants provide evidence for precipitation at the clast-pendant contact suggesting that newer deposits are not always found at the pendant terminus as other studies have assumed. These features include a void at the clast-pendant …

The Mount Feather Diamicton Of The Sirius Group: An Accumulation Of Indicators Of Neogene Antarctic Glacial And Climatic History, G. A. Wilson, J. A. Barron, A. C. Ashworth, R. A. Askin, J. A. Carter, M. G. Curren, D. H. Dalhuisen, E. I. Friedmann, D. G. Fyodorov-Davidov, D. A. Gilichinsky, M. A. Harper, David M. Harwood, J. F. Hiemstra, T. R. Janecek, K. J. Licht, V. E. Ostroumov, R. D. Powell, E. M. Rivkina, S. A. Rose, A. P. Stroeven, P. Stroeven, J. J. M. Van Der Meer, M. C. Wizevich

Department of Earth and Atmospheric Sciences: Faculty Publications

A paucity of data from the Antarctic continent has resulted in conflicting interpretations of Neogene Antarctic glacial history. Much of the debate centres on interpretations of the glacigene Sirius Group strata that crop out as discrete deposits along the length of the Transantarctic Mountains and in particular on its age and the origin of the siliceous microfossils it encloses. Pliocene marine diatoms enclosed within Sirius Group strata are inferred to indicate a dynamic East Antarctic ice sheet that was much reduced, compared with today, in the early-middle Pliocene and then expanded again in the late Pliocene. However, the geomorphology of …

Public Attitudes And Knowledge Of The Black-Tailed Prairie Dog: A Common And Controversial Species, Donna Lybecker, Berton Lee Lamb, Phadrea Ponds

United States Geological Survey: Staff Publications

Black-tailed prairie dogs (Cynomys ludovicianus; hereafter, prairie dogs) are native to the short-grass prairie region of North America from Mexico to Canada (figure 1).According to government documents (64 Federal Register 57 at 14426–14427), before the 19th century expansion of the United States, prairie dogs inhabited millions of acres of the Great Plains and lived in huge colonies west of the Missouri River. Settlement of the Great Plains and the transformation of vast areas from native grassland to tilled farmland forever changed the prairie ecosystem and prairie dog habitat.
Over the course of the last century, the habitat range …

Microbial Composition Of Near-Boiling Silica-Depositing Thermal Springs Throughout Yellowstone National Park, Carrine E. Blank, Sherry L. Cady, Norman R. Pace

Geology Faculty Publications and Presentations

The extent of hyperthermophilic microbial diversity associated with siliceous sinter (geyserite) was characterized in seven near-boiling silica-depositing springs throughout Yellowstone National Park using environmental PCR amplification of small-subunit rRNA genes (SSU rDNA), large-subunit rDNA, and the internal transcribed spacer (ITS). We found that Thermocrinis ruber, a member of the order Aquificales, is ubiquitous, an indication that primary production in these springs is driven by hydrogen oxidation. Several other lineages with no known close relatives were identified that branch among the hyperthermophilic bacteria. Although they all branch deep in the bacterial tree, the precise phylogenetic placement of many of these lineages …

Distribution Of Channel Catfish Life Stages In A Prairie River Basin, Jason C. Vokoun, Charles F. Rabeni

United States Geological Survey: Staff Publications

To describe the pattern of use by age 0, juvenile, and adult channel catfish (Ictalurus punctatus) in a prairie river basin, we collected concurrent samples from tributaries and mainstem study sites in the Grand River basin of northern Missouri. Using standardized methods, we made collections in June, August, and October of 1997 and 1998. Age 0 channel catfish were found in all three streams in August, but rarely were observed in the tributaries during October. Juveniles (ages 1-3) and adults were observed in all three streams in all three months sampled. Tag returns suggested that age 2 and …

Selection Of Nesting Habitat By Sharptailed Grouse In The Nebraska Sandhills, Bart L. Prose, Brian S. Cade, Dale Hein

United States Geological Survey: Staff Publications

We evaluated nesting habitat selection (disproportionate use compared to availability) by plains sharp-tailed grouse (Tympanuchus phasianellus jamesi) on rangelands grazed by cattle (Bas taurus) relative to height, density, and heterogeneity of residual herbaceous vegetation remaining from previous growing seasons. Residual cover is critical for nesting sharp-tailed grouse and can be lacking on grazed rangelands. Aerial photography and a geographic information system were used to analyze residual cover height classes and several measures of residual cover heterogeneity in nest (n = 38) and random (n = 38) plots. Height classes corresponded to visual obstruction readings (YORs), the …

Multiple Isotopic Investigation Of Lake Sediments From Northern India, Alice Mwanda

Masters Theses

Stable isotopes ratio of lake sediments can provide valuable environmental information. This possibility has been investigated using radiocarbon dated fossil lake sediments from the Himalayan region of Northern India. The chronology was established using Radiocarbon dating of both organic and inorganic fractions using (AMS). Inorganic ages are older than organic ages. Organic ages are expected to increase stratigraphically, however several anomalous old ages are found in the younger part of the sediments. Final chronology, determined using selected sensible ages identified two periods of sedimentation. The high sedimentation period is characterized by sedimentation rate of 0.8cm/yr and it fairly coincides with …

Satellite Imagery Proves Essential For Monitoring Erupting Aleutian Volcano, Kenneson Dean, Jonathan Dehn, Stephen R. Mcnutt, Christina Neal, Richard Moore, Dave Schneider

School of Geosciences Faculty and Staff Publications

Mt. Cleveland is one of more than 40 active volcanoes in Alaska that is monitored by the Alaska Volcano Observatory (AVO). It is located on the western half of Chuginadak, a remote and uninhabited island in the east central Aleutians that lies 1526 km southwest of Anchorage. The closest inhabited community, Nikolski, is 75 km to the east on Umnak Island (Figure 1). Mt. Cleveland erupted explosively on 19 February and on 11 and 19 March 2001. Because the volcano is not yet monitored with seismic, deformation, or other geophysical instruments, satellite imagery was the only effective tool for detecting …

Geochemistry Of Atmospheric Aerosols Generated From Lava-Seawater Interactions, Francis J. Sansone, Claudia R. Benitez-Nelson, Joseph A. Resing, Eric H. Decarlo, Sue M. Vink, Jacqueline A. Heath, Barry J. Huebert

Faculty Publications

[1] Trace elements were measured in the aerosol plume produced by lava‐seawater interactions along the shoreline of Kilauea volcano, Hawaii. Plume concentrations were normalized relative to Hawaiian basalt composition and showed a linear log‐log co‐variation with their emanation coefficient (an indicator of element volatility). Normalized aerosol concentrations also consistently covaried with corresponding normalized concentrations in dilute fumarolic gas from Kilauea volcano and fumarolic gas condensates from Kudryavy and Merapi volcanoes, despite different mechanisms of element volatilization. Conservatively estimated regional ocean deposition rates of Cu, Cd, Ni, Pb, Mn, Zn, Fe and P were >50 times background rates. Thus, upper ocean …

Land Usage Impacts On Springhead Salamander Populations, At Callaway Extended Properties, Harris County, Georgia, Neil Allen Pearce

Theses and Dissertations

Recent scientific studies have indicated that anrphibian populations appear to be declining in many areas of the world or exhibiting local population fluctuations. Some of the reasons given for this population decline are associated with land usage, and the negative biological impacts of many forms of land management practices. A study was conducted at the Callaway Gardens Extended Properties in Pine Mountain Georgia which compared the local aquatic salamander populations of five spring -fed streams in the Cason J. Callaway Memorial Forest, and five spring-fed streams in the Lower Valley Area. Using a cat ch-per-unit -effort sampling methodology, a comparison …

The Lacustrine Carbon Cycle As Illuminated By The Waters And Sediments Of Two Hydrologically Distinct Headwater Lakes In North-Central Minnesota, U.S.A., Walter E. Dean, Antje Schwalb

United States Geological Survey: Staff Publications

The accumulation rates of CaCO₃ and organic carbon (OC) in lake sediments are delicately balanced between production in the epilimnion and destruction in the hypolimnion. The cycling of these two forms of carbon makes a ‘‘carbon pump’’ that greatly affects the biogeochemical cycles of other elements. To further understand these biogeochemical dynamics, the lakes, streams, and wetlands of the Shingobee River headwater area of north-central Minnesota have been subjected to intensive hydrologic and biogeochemical studies. Williams Lake, situated close to the highest point in the regional flow system, is hydrologically closed, with no surface inlet or outlet, and ground …

Profitable And Productive Farming Systems For Management Of Nolba Catchment, B R. Eastough, Nolba Focus Catchment Group

Resource management technical reports

Summary of the main points covered at each of the several workshop and two demonstrations by the Nolba Catchment Group, Western Australia. The areas addressed include: low recharge farming systems; impact on the environment of integrated weed management; management of organic matter in soils within the catchment; dune stabilisation and groundwater hydrology.

Using Gis And Land Use Data To Select Candidate Reference Sites For Stream Bioassessment, John Robert Olson

Theses and Dissertations

GIS was used to select candidate reference sites in Georgia to characterize the reference condition by sub-ecoregion for a rapid bioassessment of streams statewide. Instead of relying on best professional judgment or previous knowledge of a limited number of sites, we performed an objective evaluation of cumulative impact on all catchments using land use data sets. These included road and impoundment data from DLGs and Multi-Resolution Land use Consortium data. Land use impairment was measured as percentages of forest, urban, pasture, row crops, and barren area for both the entire catchment and for 10, 40, and 130-m riparian buffers, road …

Bioavailability/Toxicity Of Iron From Aerobically Processed Organic Fertilizer, Stacey Marie Wilson

Undergraduate Honors Capstone Projects

For an undergraduate Honor's project, I worked under the direction of Dr. Jeffery Hall to determine the bioavailability and toxicity of iron from Milorganite® fertilizer, an aerobically processed organic fertilizer. The Milorganite® Company is a subsidiary of the Milwaukee Municipal Sewage District and produces a fertilizer of high iron content (approximately 5-7%). The high iron content has resulted in concern about the toxic potential, which until now was unknown. This thesis paper will explain iron chemistry, bioavailability, requirements, absorption, toxicity, and treatments, followed by a description of fertilizer types and contents. This will be followed by a description and reasoning …

Stratigraphy And Paleoecology Of The Morrison Formation, Como Bluff, Wyoming, Melissa V. Connely

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Morrison Formation at Como Bluff, Wyoming, has been historically known for containing a rich source of Late Jurassic vertebrate fossils. However, when collected, most of these fossils were not positioned into a stratigraphic or sedimentologic framework. Research shows that the Morrison Formation at Como Bluff can be divided into three members. These members can be identified by lithologic and paleontological characteristics. The lower Morrison members include the Windy Hill Member and the recently described Lake Como Member. The Windy Hill Member primarily contains near-shore marine sandstone. Megavertebrate fauna is lacking. The Lake Como Member contains illitic clay in red …

A Macroterrain Landtype Association Classification Model For The Great Basin, Frank L. Dougher

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Three Macroterrain Landtype Association classification models were developed to stratify and categorize Utah's West Desert. These models approached terrain segmentation using an energy-flow paradigm from erosional to transitional to depositional landscape. One model was developed as a slope-backed deterministic model that used slope-threshold limits to discriminate between Landtype Associations. A second model was developed as a stochastic, training-data driven supervised classification, using comparative t-values to classify the landscape to the most similar landtype class. The third model was a probabilistic algorithm, which classified the landscape to the most probable class based on multiple iterations of the stochastic model. These …