The following posters represented the geosciences at CUR’s Posters on the Hill, April 19-20, 2016.
Student: Miles T. Bengtson
Research Institution: Embry-Riddle Aeronautical University
Lead Student Home Institution: Embry-Riddle Aeronautical University
Lead Student Home State: NC
Faculty Mentor: Dr. Anatoly V. Streltsov
Sponsoring Agency (Grant #): Embry-Riddle Office of Undergraduate Research
Title: Obser vations and Simulations of Whistler Waves in the Van Allen Radiation Belts
Abstract:When the first American satellite, Explorer I, was launched into space it inadvertently discovered one the most significant features of our local space environment: the Van Allen Radiation Belts. This region contains highly energetic particles which are trapped in the geomagnetic field. These particles are extremely hazardous for spacecraft, causing damage to electronics and endangering astronauts on the International Space Station. Certain natural or artificial events, such as coronal mass ejections or high-altitude nuclear explosions, can enhance the Radiation Belts and decrease satellite lifetimes from years to months.Therefore, one of the most critical national defense objectives is to develop a process to remediate the radiation and protect our assets in space from this threat. Our research involves one promising remediation mechanism based on the interactions between these particles and very-low-frequency electromagnetic waves known as whistlers. One important property of whistler waves is that they can be guided along narrow inhomogeneities of plasma density called ducts.To understand the ducting mechanism one needs to compare theoretical predictions with in-situ observations of waves and particles in the magnetosphere. We have analyzed several events of ducted whistlers observed by the Van Allen Probes satellites and reproduce them with numerical simulations based on whistler theory.We demonstrate good, quantitative agreement between our simulations and the observations, indicating that our model successfully explains a majority of the existing satellite observations and can be used to predict the results from future experiments of launching whistler waves into the Radiation Belts from ground transmitters and spacecraft.
Students: David A McLennan, and Erika Smith
Research Institution: Indiana State University
Lead Student Home Institution: Indiana State University
Lead Student Home State: IN
Faculty Mentors: Dr. Jennifer C Latimer, and Dr. Jeffery R Stone
Sponsoring Agency (Grant #): National Science Foundation, and the US Geological Survey
Poster Title: “Monitoring Increased Nutrient Loads on a Lake Acting as a Heavy Metal Reservoir”
Abstract: GreenValley Lake State Fishing Area in west-central Indiana once served as a water supply reservoir for the adjacent and now abandoned GreenValley Coal Mine (operated from 1948-1963).The mine property continues to discharge acidic drainage despite reclamation efforts into GreenValley Lake and the connected Scott Lake Fish and Wildlife Areas.To evaluate the variability of metal and nutrient loads over time, two short sediment cores were collected from Green Valley Lake in spring 2014 (38cm) and spring 2015 (39cm). Metal concentrations were determined by a portable X-ray fluorescence analyzer after the cores were separated into 0.5 cm samples. Approximately 20% of the metal concentrations will be verified by ICP-OES following extraction in 50% aqua regia. Detailed phosphorus (P) geochemistry was determined using a sequential extraction technique (SEDEX).The sediments in the lake are characterized by heavy metal concentrations elevated above typical background levels. These metals tend concentrate near the sediment water interface, often 2-5 times greater than the average for the sediments below.This suggests they are diagenetically mobile, possibly diffusing out of the sediments under low oxygen conditions and returning to the sediments when oxygen returns.The most dramatic shift in the detailed P geochemistry is the significant reduction of mineral P at 15 cm and increasing importance of oxide-associated and adsorbed P upcore. Diatom assemblages suggest increasing eutrophication. As nutrient loads continue to increase, the oxygen depleted zone may expand impacting fish populations and change water geochemistry significantly, in particular by mobilizing heavy metals.
Student: John Warnock
Research Institution: Carthage College
Lead Student Home Institution: Car thage College
Lead Student Home State: IL
Faculty Mentor: Dr.Wenjie Sun
Poster Title: “Is cycling as an active transpor tation more than environmentally friendly?—Impacts of bicycle networks on property values in Madison,WI”
Abstract: Whether it is a simple bike path in a park or a complex network of trails and bike lanes, bicycling infrastructure positively impacts the economy. Networks promote active transportation which results in both public and personal economic benefits.The community benefits from reduced infrastructure and health costs, reduced vehicle emissions, and increased revenues to local businesses. Individuals benefit through a healthier lifestyle as well as reduced transportation and medical expenses.There is also an economic effect on property values. Opinions vary whether a bike trail will increase or decrease the value of properties near it.While opponents feel that privacy decreases and crime increases near a bike trail, most studies have shown that bike trails will increase property values. ,This study focuses on the effect bicycle trails have on property values in Madison, WI. Madison has a well-developed cycling network which acts as a corridor for transportation and recreation. While only 0.6% of workers in the U.S. commute to work by bicycle, the percentage is much higher in Madison at 5.3%. In this study, through the use of geographic information system (GIS), maps were created and statistical analyses were run to determine how assessed values of single family residential properties vary by the home’s proximity to the nearest off-street, paved bike trail. Many variables relating to the attributes of properties were also incorporated in this research.The results show a statistically significant effect of a home’s distance to the nearest bike trail on assessed value together with other property characteristics.