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Trouble Breathing?, Storm Project Jan 2007

Trouble Breathing?, Storm Project

Open Educational Resources

Objective:

Students will make connections from everyday situations to air quality. Students will know the 7 criteria pollutants established by the EPA and monitored by each state.

National Science Education Standard:

As a result of activities in grades 5-8, students w ill learn that natural environments may contain substances that are harmful to human beings. Maintaining environmental health involves establishing or monitoring quality standards related to use of soil, water, and air.


There's A Whole Lotta Spillin' Goin' On!, Storm Project Jan 2007

There's A Whole Lotta Spillin' Goin' On!, Storm Project

Open Educational Resources

Unit Learning Objectives: The learner should be able to:

1. Compare and contrast hazardous chemical spills
2. Comprehend how hazardous chemicals affect the environment.
3. Explain the difficulty involved in cleaning up a
hazardous spill.
4. Explain how the chemical travels once it is released.
5. Assess how hazardous chemicals affect the human body and animal life.
6. Analyze a chemical spill and its affects on its
surroundings.
7. Create an emergency management system based on a real life situation

Evidence of Understanding: By the end of this unit, students should be able to demonstrate a clear understanding of hazardous …


Be Particular About Our Matter!, Storm Project Jan 2007

Be Particular About Our Matter!, Storm Project

Open Educational Resources

Objectives:

--Demonstrate that particulate air pollution can be invisible to the eye.
--Students will collect and observe particulate matter.
--Students will identify pollen grains and make their own pollen map for Davenport.
-- Students will collect and interpret local environmental maps.
--Students will investigate health risks involved in polluted air.

National Science Education Standards:

  • Standard A: Students will conduct scientific inquiry
  • Standard B: Teacher will guide and facilitate a learning environment.
  • Standard D: Students will be provided with time, space and resources toconduct their research.
  • Standard F: Risks and benefits; Science and technology in society


Factories - Friends Or Foes?, Storm Project Jan 2007

Factories - Friends Or Foes?, Storm Project

Open Educational Resources

Objective: Students will be able to role play various points of view considering placement of a factory and its effects on air quality.

National Science Education Standards:

Standard E - Understandings about science and technology

Standard F -

  • Personal health
  • Populations, resources, and environments
  • Natural hazards
  • Risks and benefits
  • Science and technology in society

Standard G - Science as a human endeavor


Droughtscape, Winter 2007, Kelly Smith Jan 2007

Droughtscape, Winter 2007, Kelly Smith

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

Subscribe Now!

Policy Update: NIDIS is Law. What’s Next?

What Would You Like to See?

TX, OK, Plains, Southwest Hardest Hit in 2006

Climatologically Speaking, How Bad Was It?

State Spotlight: Arizona

Drought Decision-Support Tools Evolving


Regional Groundwater Quality In Watersheds Of The Upper Cumberland, Lower Cumberland, And Lower Tennessee Rivers, And The Jackson Purchase Region (Kentucky Basin Management Unit 3), R. Stephen Fisher, Bart Davidson, Peter T. Goodmann Jan 2007

Regional Groundwater Quality In Watersheds Of The Upper Cumberland, Lower Cumberland, And Lower Tennessee Rivers, And The Jackson Purchase Region (Kentucky Basin Management Unit 3), R. Stephen Fisher, Bart Davidson, Peter T. Goodmann

Report of Investigations--KGS

The Kentucky Geological Survey and the Kentucky Division of Water are evaluating groundwater quality throughout the commonwealth to determine regional conditions, assess impacts of nonpoint-source contaminants, provide a baseline for tracking changes, and provide essential information for environmental-protection and resource-management decisions. This report summarizes expanded groundwater monitoring activities and groundwater quality in watersheds of the Upper Cumberland River, Lower Cumberland River, Tennessee River, and the Jackson Purchase Region (Kentucky Basin Management Unit 3).

Thirty wells and springs were sampled seasonally between the summer of 2000 and the spring of 2001, and analyzed at the Kentucky Division of Environmental Services Laboratory. …


Simulations Of Ground-Water Flow, Transport, Age, And Particle Tracking Near York, Nebraska, For A Study Of Transport Of Anthropogenic And Natural Contaminants (Tanc) To Public-Supply Wells, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Hornberger Jan 2007

Simulations Of Ground-Water Flow, Transport, Age, And Particle Tracking Near York, Nebraska, For A Study Of Transport Of Anthropogenic And Natural Contaminants (Tanc) To Public-Supply Wells, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Hornberger

United States Geological Survey: Publications

The U.S. Geological Survey (USGS) is committed to providing the Nation with credible scientific information that helps to enhance and protect the overall quality of life and that facilitates effective management of water, biological, energy, and mineral resources (http://www.usgs.gov/). Information on the Nation’s water resources is critical to ensuring long-term availability of water that is safe for drinking and recreation and is suitable for industry, irrigation, and fish and wildlife. Population growth and increasing demands for water make the availability of that water, now measured in terms of quantity and quality, even more essential to the long-term sustainability of our …


Monitoring Changes In Geothermal Activity At Norris Geyser Basin By Satellite Telemetry, Yellowstone National Park, Wyoming, Irving Friedman Jan 2007

Monitoring Changes In Geothermal Activity At Norris Geyser Basin By Satellite Telemetry, Yellowstone National Park, Wyoming, Irving Friedman

United States Geological Survey: Publications

Instrumentation on a weir on Tantalus Creek, which captures 98 percent of the surface discharge of Norris Geyser Basin, Yellowstone National Park (the Park), records discharge and water temperature every 10 minutes and telemeters recorded data every hour via GOES satellite. Plots of discharge from June 1998 through mid-November 2003 record frequent—and often large—changes in
discharge.

Data recorded during five eruptions of Steamboat Geyser (May 2000, April 2002, September 2002, April 2003, and October 2003) allow calculation of the time and duration of the eruptions, as well as amounts of water released by each eruption.

Water discharge at the weir …


Investigations Of The Effects Of Synthetic Chemicals On The Endocrine System Of Common Carp In Lake Mead, Nevada And Arizona, Michael R. Rosen, Steven L. Goodbred, Reynaldo Patiño, Thomas J. Leiker, Erik Orsak Jan 2007

Investigations Of The Effects Of Synthetic Chemicals On The Endocrine System Of Common Carp In Lake Mead, Nevada And Arizona, Michael R. Rosen, Steven L. Goodbred, Reynaldo Patiño, Thomas J. Leiker, Erik Orsak

United States Geological Survey: Publications

Lake Mead is the largest reservoir by volume in the United States and was created by the construction of the 221-meter high Hoover Dam in 1935 at Black Canyon on the lower Colorado River between Nevada and Arizona (fig. 1). Inflows of water into the lake include three rivers, Colorado, Virgin, and Muddy; as well as Las Vegas Wash, which is now perennial because of discharges from municipal wastewater treatment plants (Covay and Leiker, 1998) and urban stormwater runoff. As the population within the Las Vegas Valley began to increase in the 1940s, the treated effluent volume also has increased …


Applications Of Trace-Element And Stable-Isotope Geochemistry To Wildlife Issues, Yellowstone National Park And Vicinity, Maurice A. Chaffee, Wayne C. Shanks Iii, Robert O. Rye, Charles C. Shwartz, Monique G. Adams, Robert R. Carlson, James G. Crock, Pamela A. Gemery-Hill, Kerry A. Gunther, Cynthia L. Kester, Harley D. King, Shannon R. Podruzny Jan 2007

Applications Of Trace-Element And Stable-Isotope Geochemistry To Wildlife Issues, Yellowstone National Park And Vicinity, Maurice A. Chaffee, Wayne C. Shanks Iii, Robert O. Rye, Charles C. Shwartz, Monique G. Adams, Robert R. Carlson, James G. Crock, Pamela A. Gemery-Hill, Kerry A. Gunther, Cynthia L. Kester, Harley D. King, Shannon R. Podruzny

United States Geological Survey: Publications

Reconnaissance investigations have been conducted to identify how geochemical techniques can be applied to biological studies to assist wildlife management in and near Yellowstone National Park (the Park). Many elements (for example, As, B, Be, Ce, Cl, Cs, F, Hg, K, Li, Mo, Rb, S, Sb, Si, and W) are commonly enriched in (1) thermal waters in the Yellowstone area, (2) rocks altered by these waters, (3) sinter and travertine deposits, and (4) soils and stream sediments derived from these rocks. Some of these elements, such as As, F, Hg, and Mo, may be toxic to wildlife and could be …


Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May Jan 2007

Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May

United States Geological Survey: Publications

This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 …


Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales1, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson Jan 2007

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales1, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …


Butterfly Responses To Prairie Restoration Through Fire And Grazing, Jennifer A. Vogel, Diane M. Debinski, Rolf R. Koford, James R. Miller Jan 2007

Butterfly Responses To Prairie Restoration Through Fire And Grazing, Jennifer A. Vogel, Diane M. Debinski, Rolf R. Koford, James R. Miller

United States Geological Survey: Staff Publications

The development of land for modern agriculture has resulted in losses of native prairie habitat. The small, isolated patches of prairie habitat that remain are threatened by fire suppression, overgrazing, and invasion by non-native species. We evaluated the effects of three restoration practices (grazing only, burning only, and burning and grazing) on the vegetation characteristics and butterfly communities of remnant prairies. Total butterfly abundance was highest on prairies that were managed with burning and grazing and lowest on those that were only burned. Butterfly species richness did not differ among any of the restoration practices. Butterfly species diversity was highest …


Factors Influencing Movement Probabilities Of Big Brown Bats (Eptesicus Fuscus) In Buildings, Laura E. Ellison, Thomas J. O’Shea, Daniel J. Neubaum, Richard Bowen Jan 2007

Factors Influencing Movement Probabilities Of Big Brown Bats (Eptesicus Fuscus) In Buildings, Laura E. Ellison, Thomas J. O’Shea, Daniel J. Neubaum, Richard Bowen

United States Geological Survey: Staff Publications

We investigated movements of female big brown bats (Eptesicus fuscus) roosting in maternity colonies in buildings in Fort Collins, Colorado (USA), during the summers of 2002, 2003, and 2005. This behavior can be of public health concern where bats that may carry diseases (e.g., rabies) move among buildings occupied by people. We used passive integrated transponders (PIT tags) to mark individual bats and hoop PIT readers at emergence points to passively monitor the use of building roosts by marked adult females on a daily basis during the lactation phase of reproduction. Multi-strata models were used to examine movements …


Fundulus As The Premier Teleost Model In Environmental Biology: Opportunities For New Insights Using Genomics, Karen G. Burnett, Lisa J. Bain, William S. Baldwin, Gloria V. Callard, Sarah Cohen, Richard T. Di Giulio, David H. Evans, Marta Gómez-Chiarri, Mark E. Hahn, Cindi A. Hoover, Sibel I. Karchner, Fumi Katoh, Deborah L. Maclatchy, William S. Marshall, Joel N. Meyer, Diane E. Nacci, Marjorie F. Oleksiak, Bernard B. Rees, Thomas D. Singer, John J. Stegeman, David W. Towle, Peter A. Van Veld, Wolfgang K. Vogelbein, Andrew Whitehead, Richard N. Winn, Douglas L. Crawford Jan 2007

Fundulus As The Premier Teleost Model In Environmental Biology: Opportunities For New Insights Using Genomics, Karen G. Burnett, Lisa J. Bain, William S. Baldwin, Gloria V. Callard, Sarah Cohen, Richard T. Di Giulio, David H. Evans, Marta Gómez-Chiarri, Mark E. Hahn, Cindi A. Hoover, Sibel I. Karchner, Fumi Katoh, Deborah L. Maclatchy, William S. Marshall, Joel N. Meyer, Diane E. Nacci, Marjorie F. Oleksiak, Bernard B. Rees, Thomas D. Singer, John J. Stegeman, David W. Towle, Peter A. Van Veld, Wolfgang K. Vogelbein, Andrew Whitehead, Richard N. Winn, Douglas L. Crawford

United States Environmental Protection Agency: Publications

A strong foundation of basic and applied research documents that the estuarine fish Fundulus heteroclitus and related species are unique laboratory and field models for understanding how individuals and populations interact with their environment. In this paper we summarize an extensive body of work examining the adaptive responses of Fundulus species to environmental conditions, and describe how this research has contributed importantly to our understanding of physiology, gene regulation, toxicology, and ecological and evolutionary genetics of teleosts and other vertebrates. These explorations have reached a critical juncture at which advancement is hindered by the lack of genomic resources for these …


Nutrient Concentrations At Baseflow Conditions In The Upper White River Basin, Southwest Missouri And Northwest Arkansas, Gopala G. Borchelt Jan 2007

Nutrient Concentrations At Baseflow Conditions In The Upper White River Basin, Southwest Missouri And Northwest Arkansas, Gopala G. Borchelt

Graduate Theses/Dissertations

The Upper White River Basin (UWRB) is becoming increasingly vulnerable to water quality degradation from urban/population growth and increased agricultural production. This study examines the relationships among nutrient levels, water chemistry and watershed characteristics of 19 watersheds in the UWRB. Water samples were collected during baseflow conditions each month for one year at USGS continuous-flow gage stations. Watershed characteristics evaluated were land use, geology, drainage area, flow discharge, and wastewater treatment plant discharge (WTP). Measured chemical water quality indicators include total nitrogen (TN), total phosphorus (TP), specific conductivity, turbidity, pH and dissolved oxygen. Rapidly expanding urban areas are associated with …


Quartz Grain Surface Textures As Indicators Of Infilling Processes And Depositional Environments Associated With Ice-Wedge Casts In Northeast Iowa, Michael Loux Jan 2007

Quartz Grain Surface Textures As Indicators Of Infilling Processes And Depositional Environments Associated With Ice-Wedge Casts In Northeast Iowa, Michael Loux

Honors Program Theses

Ice-wedge casts and polygonal patterned ground are common features of the Iowan Surface of Northeast Iowa. Paleoenvironmental studies in Iowa and adjacent states indicate that tundra conditions existed in Northeast Iowa between 21,000 and 16,500 years BP, the coldest part of late \\'.'isconsinan time. Degradation of permafrost and formation of ice-wedge casts must have occurred near the end of this cold climate episode, which also promoted extreme erosion of the landscape in Northeast Iowa. The sediment-filled wedges in Northeast Iowa occur in pre-Illinoian till with the infilling material consisting mostly of sand. The details of the infilling history of the …


Bomb-Spike Dating Of A Mummified Baboon In Ludwig Cave, Namibia, Greg Hodgins, George A. Brook, Eugene Marais Jan 2007

Bomb-Spike Dating Of A Mummified Baboon In Ludwig Cave, Namibia, Greg Hodgins, George A. Brook, Eugene Marais

International Journal of Speleology

In 1982 a mummified adult female baboon was discovered on a ledge in Ludwig Cave in Namibia. A toe bone was removed for dating in July 1995. AMS radiocarbon dating of bone collagen, tendon, and skin indicates a post-modern age. Application of the atomic bomb-spike calibration curve suggests death in late 1977 and an age at death of around 19 years. Baboons roost in the cave and the mummified female, along with a mummified juvenile male discovered in 2002 and three rotting corpses discovered in 1995, were probably chased by other baboons or by leopards down a ca. 6 m …


Acadian Biospeleology: Composition And Ecology Of Cave Fauna Of Nova Scotia And Southern New Brunswick, Canada, Max Moseley Jan 2007

Acadian Biospeleology: Composition And Ecology Of Cave Fauna Of Nova Scotia And Southern New Brunswick, Canada, Max Moseley

International Journal of Speleology

The vertebrate and invertebrate fauna, environment and habitats of caves and disused mines in Nova Scotia and southern New Brunswick are provisionally catalogued and described, based on field collections made over many years. The area was glaciated and the subterranean fauna consists of non-troglobites all of which have arrived and colonised the caves during or following final recession of the Pleistocene glaciers. The statistical composition of the fauna at the higher taxonomic level is similar to that in Ontario, but is less species rich and there are some notable ecological and other differences. Porcupine dung accumulations are an important habitat …


A Taxonomic Survey Of Lamp Flora (Algae And Cyanobacteria) In Electrically Lit Passages Within Mammoth Cave National Park, Kentucky, Thomas Smith, Rick Olson Jan 2007

A Taxonomic Survey Of Lamp Flora (Algae And Cyanobacteria) In Electrically Lit Passages Within Mammoth Cave National Park, Kentucky, Thomas Smith, Rick Olson

International Journal of Speleology

A taxonomic survey of the lamp flora from electrically lit passages in Mammoth Cave, Mammoth Cave National Park, identified 28 species. Overall, cyanobacteria were dominant represented by 14 species (50% of the total), green algae had eight species (29%), and six diatoms species (21%) were present. There was not a correlation between species diversity and temperature, but there is a general trend of increasing diversity with warmer temperatures. There were two algal or cyanobacterial species identified in this study that overlapped with previous studies. There is a lack of continuity between previous studies only having one species identified in more …


Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke Jan 2007

Impact Of Land Use On Water Quality In The Indian Lake Watershed: An Integrated Geographic Information Systems Approach, Michael Belke

Browse all Theses and Dissertations

Geology and land use and land cover are the most important factors that influence water quality. The purpose of this study is to investigate how these factors operate in a rural watershed. Specifically, this thesis tests the feasibility of a proposed formula to relate how land use affects surface water quality and to infer hydrogeochemical reactions that control water chemistry through hydrogeochemical speciation and mineral stability relationships. Samples were collected from Indian Lake and its watershed in West-Central Ohio. BASINS, produced by the USEPA, was then used to delineate sub-watersheds and find the land use areas of these watersheds. The …


Dinosaur Tectonics: A Structural Analysis Of Theropod Undertracks With A Reconstruction Of Theropod Walking Dynamics, Ole Graversen, Jesper Milán, David B. Loope Jan 2007

Dinosaur Tectonics: A Structural Analysis Of Theropod Undertracks With A Reconstruction Of Theropod Walking Dynamics, Ole Graversen, Jesper Milán, David B. Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

A dinosaur trackway in the Middle Jurassic eolian Entrada Sandstone of southern Utah, U.S.A., exposes three undertracks that we have modeled as isolated tectonic regimes showing the development of fold-thrust ramp systems induced by the dinosaur’s feet. The faulted and folded sequence is comparable to crustal-scale tectonics associated with plate tectonics and foreland fold-thrust belts. A structural analysis of the dinosaur tracks shows the timing and direction of the forces exercised on the substrate by the animal’s foot during the stride. Based on the structural analysis, we establish a scenario for foot movements and weight distribution in the feet. During …


Preservation And Erosion Of Theropod Tracks In Eolian Deposits: Examples From The Middle Jurassic Entrada Sandstone, Utah, U.S.A., Jesper Milán, David B. Loope Jan 2007

Preservation And Erosion Of Theropod Tracks In Eolian Deposits: Examples From The Middle Jurassic Entrada Sandstone, Utah, U.S.A., Jesper Milán, David B. Loope

Department of Earth and Atmospheric Sciences: Faculty Publications

The Middle Jurassic Entrada Sandstone, exposed near the town of Escalante, southern Utah, consists of large-scale cross-bedded eolian deposits that are interbedded with horizontally laminated sand sheets and thin sets of eolian cross-strata, representing periods with a moister climate. The flat-bedded units contain numerous tracks and trackways from small to large-sized theropod dinosaurs. These tracks are today exposed in several distinct erosional states, allowing detailed studies of track and undertrack formation in eolian deposits. Tracks that originally were emplaced on sloping surfaces show, in their present-day erosional state, a morphology distinct from those originally emplaced on horizontal surfaces. Further, the …


Sexual Selection Drives Speciation In An Amazonian Frog, Kathryn E. Boul, W. Chris Funk, Catherine R. Darst, David C. Cannatella, Michael J. Ryan Jan 2007

Sexual Selection Drives Speciation In An Amazonian Frog, Kathryn E. Boul, W. Chris Funk, Catherine R. Darst, David C. Cannatella, Michael J. Ryan

United States Geological Survey: Staff Publications

One proposed mechanism of speciation is divergent sexual selection, whereby divergence in female preferences and male signals results in behavioural isolation. Despite the appeal of this hypothesis, evidence for it remains inconclusive. Here, we present several lines of evidence that sexual selection is driving behavioural isolation and speciation among populations of an Amazonian frog (Physalaemus petersi). First, sexual selection has promoted divergence in male mating calls and female preferences for calls between neighbouring populations, resulting in strong behavioural isolation. Second, phylogenetic analysis indicates that populations have become fixed for alternative call types several times throughout the species’ range, …


New Insights Into Marine Migration And Winter Habitat Of Gulf Sturgeon, Randy E. Edwards, Frank M. Parauka, Kenneth J. Sulak Jan 2007

New Insights Into Marine Migration And Winter Habitat Of Gulf Sturgeon, Randy E. Edwards, Frank M. Parauka, Kenneth J. Sulak

United States Geological Survey: Staff Publications

Migrations and movements of Gulf sturgeon Acipenser oxyrinchus desotoi were determined using satellite pop-up archival transmitting (PAT) tags and acoustic telemetry. Adult Gulf sturgeon from four rivers in northwestern Florida were caught with gill nets and were tagged with PAT and acoustic tags in the fall of 2001 and 2002. PAT tags were programmed to release in early February 2002 and 2003 to provide information about location of late-winter marine habitats. However, only 5 of 25 provided meaningful location information. Three of the PAT-tagged fish were relocated acoustically near the PAT tag pop-up locations, one of which was in Choctawhatchee …


Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson Jan 2007

Hydrologic Connectivity And The Contribution Of Stream Headwaters To Ecological Integrity At Regional Scales, Mary C. Freeman, Catherine M. Pringle, C. Rhett Jackson

United States Geological Survey: Staff Publications

Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified by land uses that alter …


Dune Fields: Mid-Latitudes, J. Sun, Daniel R. Muhs Jan 2007

Dune Fields: Mid-Latitudes, J. Sun, Daniel R. Muhs

United States Geological Survey: Staff Publications

Large dune fields, or sand seas, are landscapes often thought to be found only in deserts beneath the great, subtropical high-pressure zones, where subsiding air suppresses rainfall. Dune fields are also quite common in mid-latitude regions, to the north and south of subtropical deserts (Fig. 1). Two major characteristics distinguish many mid-latitude dune fields from the sand seas of lower latitudes. One difference is that many of those in mid-latitudes are in semiarid, rather than arid climates, and therefore are not presently active. In this article, ‘active’ refers to eolian sand bodies that are not covered with vegetation, and where …


Biogeography And The Cambrian Radiation Of Arachnomorph Arthropods, Jonathan R. Hendricks, Bruce S. Lieberman Jan 2007

Biogeography And The Cambrian Radiation Of Arachnomorph Arthropods, Jonathan R. Hendricks, Bruce S. Lieberman

Faculty Publications

Biogeographic patterns in primarily Cambrian arachnomorph taxa are investigated using a recently constructed phylogenetic hypothesis in order to explore the biogeographic context of the Cambrian radiation. A modified version of Brooks Parsimony Analysis is employed to elucidate patterns of vicariance and geodispersal in taxa from six regions (Laurentia, Baltica, Siberia, Australia, Africa and China). Well resolved vicariance and geodispersal trees are very similar and reconstruct Laurentia and China as sister areas. This close area relationship between Laurentia and China provides extensive evidence for congruent vicariance and range expansion in Cambrian arachnomorphs, while data from trilobites do not show this pattern. …


Assessment Of The Source And Transformation Of Nitrate In The Cedar River Watershed By Using Stable Isotopes Of Nitrogen, Sushil Gautam Jan 2007

Assessment Of The Source And Transformation Of Nitrate In The Cedar River Watershed By Using Stable Isotopes Of Nitrogen, Sushil Gautam

Dissertations and Theses @ UNI

Stable isotopes of nitrogen were used to assess the source and fate of nitrate in the Cedar River Watershed, Iowa. Ground water samples from 20 private wells and surface water samples from 10 sites in the Cedar River and its tributaries were collected. A total of 90 samples were collected during the growing season from May through September 2006. In 35% of the wells, nitrate concentration exceeded the U.S. Environmental Protection Agency's recommended maximum contaminant level (MCL) of 45 mg/1 (as NO3-) for drinking purposes. Eight (8) out of 10 samples exceeded MCL for nitrate in the first set of …


An Investigation Of Lead And Other Metal Contaminants In The Sediments Of Clearwater Lake, Missouri, Gary W. Krizanich Jan 2007

An Investigation Of Lead And Other Metal Contaminants In The Sediments Of Clearwater Lake, Missouri, Gary W. Krizanich

Doctoral Dissertations

"The purpose of this investigation is to characterize the spatial and temporal distribution and concentration of trace metals in sediments of Clearwater Lake. Understanding how trace metals are released to and transported in aquatic environments is important to the overall understanding of the impacts of mining on the natural environment. The main focus of this research will be on historic sedimentation within Clearwater Lake, which may act as a sink where mining related trace metals are stored. Because of their high preservation rates in basins, sediments can provide detailed chronostratigraphic histories of trace metal inputs in lakes. Sediment records can …