2012 Grant Recipients

Chelsie Dugan ($2,100)
M.S. Student
Department of Geological Sciences
Ball State University

Investigating Vadose-Zone Hydrology in Karst Aquifers using Quantitative Groundwater Tracing Methods: Timpanogos Cave National Monument, Utah

Abstract - During the spring and summer of 2012, I will undertake water-tracing and groundwater investigations at Timpanogos Cave National Monument (TICA) to help National Park Service resource managers understand the scope and characteristics of the watershed that contributes to the many cave pools in this important tourist destination in the American Fork Canyon near Provo, Utah. More specifically, I propose a series of dye trace experiments, geochemistry studies, and water isotope investigations to assess the water quality and hydrologic function of the contributing watershed to TICA, which is hypothesized to extend into adjacent United States Forest Service (USFS) lands. These USFS lands above the American Fork River and on the slopes of Mount Timpanogos are subjected to recreational off-road vehicle use, snowmobiling, commercial ranching, and mining. Each of these activities presents a potential source of contamination to surface waters that may enter the cave ecosystem. TICA managers are particularly concerned with potential contamination derived from recreational activities on these USFS lands.

Brett R. Gerard ($1,600)
M.S. Student
Department of Biology, Aquatic Resources Program
Texas State University-San Marcos

Modeling Precipitation Thresholds Required for Recharge into a Central Texas Karst Aquifer and the Influence of Barometric Pressure on Cave Drip Rates

Abstract- Karst aquifers supply water for many aquatic ecosystems and an estimated 20% of the world's population (Ford and Williams 2007). Growing populations in karst regions place increasing demands on water in these systems, and to sustain the ecosystems and communities that rely on them, better management strategies are needed.

My research objectives are twofold. First, I plan to quantify the complex effects of antecedent hydrologic and environmental conditions on precipitation thresholds which must be exceeded in order for diffuse and direct recharge to occur in karstic aquifers in the Edwards Plateau, Central TX, USA. To do this, I will use precipitation, environmental and in-cave drip and stream-discharge data to examine the complex relationship between precipitation and recharge. I will also use continuous and periodic geochemical and stable isotope data to develop hydrograph separation curves for responses under variable hydrologic and environmental conditions.

Secondly, I will examine the relationship between cave speleothem drip rates and barometric pressure. To do this I will use the same in-cave drip data used in objective one along with surface and in-cave atmospheric pressure data. Preliminary data show a strong anti-correlation between barometric pressure and cave drip rate; consistent with the findings of Genty and Deflandre (1998). Preliminary data also show a strong anti-correlation between barometric pressure and drip water specific conductance, a trend not observed by Genty and Deflandre (1998). Ultimately, the results of my research will provide information required for developing better recharge models, which are necessary for groundwater modeling and environmental management strategies.

Patricia Kambesis ($3,000)
Ph.D. Candidate
Department of Geoscience
Mississippi State University

Speleogenetic Mechanisms in the Eastern Yucatan Peninsula, Quintana Roo, Mexico

Abstract - Carbonate islands and continental coastlines share a unique regional hydrology where cave development results from the interaction of a freshwater lens and marine waters. The regional hydrology is a function of catchment size and type of recharge. Hydrology is affected by eustatic sea-level changes and/or tectonics and can result in polygenetic caves that developed at different elevations and are overprinted with features associated with diffuse and/or turbulent flow. It has been suggested that island size controls the nature of cave development. Small islands have large perimeter-to-area ratios, and meteoric catchment can easily be discharged to the sea as diffuse flow, creating classic flank margin cave conditions. As islands grows larger, area increases by the square, but perimeter increases linearly. Since meteoric catchment increases faster than the available discharge perimeter, diffuse flow paths become longer. Under these conditions conduit flow becomes sustainable and cave development makes a switch to integrated turbulent flow systems. Just as with islands, cave development on continental carbonate coastlines is also a function of catchment and recharge on a regional scale. The Yucatan Peninsula exemplifies complex regional coastal hydrology that has been subject to eustatic sea-level changes. In the Yucatan, these conditions are expressed as different types of caves, from vast underwater cave systems to flank margin caves as end members. The purpose of this study is to determine the speleogenetic mechanisms that have resulted in the formation of a spectrum of caves types in close geographic proximity that range from turbulent flow to diffuse-flow systems.

Amy R. Michael ($1,700)
Ph.D. Candidate
Department of Anthropology
Michigan State University

The Use of Dental Microscopy in the Investigation of Social Experience and Status of Non-Elites in Ancient Maya Cave and Rockshelter Mortuary Sites: Interpreting Health Differences in Disparate Social Groups in the Caves Branch River Valley, Belize

Abstract -The ancient Maya subscribed to an ideological system that was deeply entrenched in the assignation of supernatural powers to earthly features. Caves figure prominently in Mayan ritual beliefs, a notion reflected by the burial of the dead in these environments. While archaeologists have long known of the presence of human remains in caves, explanations for these interments vary from evidence for human sacrifice to ancestor worship to expedient disposal of the dead.

The aim of this project is to use standardized scanning electron microscopy methods to analyze the dental microstructure of individuals buried in caves and rockshelters in order to assess health quality and to infer social experience, especially that of the non-elite population. Biological data (to investigate health) and archaeological data (to investigate use of cave and rockshelter mortuary space) are employed to determine if there is validity to the hypothesis that caves were restricted zones reserved for elites, while rockshelters were openly accessed repositories for non-elites.

A binary model of health stress (elites did not suffer, while non-elites suffered greatly) likely does not encapsulate the experience of either group and does not explain the subtle, graded stratifications within the overarching social hierarchy. Analysis of these mortuary environments will reveal information on Maya lifeways and death rituals, leading to a better understanding of the importance and use of caves in ancient burial programs. This project combines the disciplines of archaeology, physical anthropology, and geochemistry to analyze mortuary data and to make inferences about prehistoric ritual behavior.

Gilman Ouellette ($1,500)
M.S. Student
Department of Geography and Geology
Western Kentucky University

Paleohydrology and Climate Change in the Eastern Caribbean from Barbadian Speleothems

Abstract -Ground water resources on island nations such as Barbados are highly sensitive to changes in precipitation regimes. To understand and manage water resources most effectively, a strong understanding of the geographically unique climate/ground water interactions is necessary. To this end a high-resolution reconstruction of late Holocene precipitation on the island of Barbados will be reconstructed from multiple speleothem stable oxygen isotope records. The reconstructed paleoprecipitation patterns will be analyzed using time series analysis, elucidating the role major climate influences play in modulating water availability throughout the Late Holocene. This research will provide insight into how the climate of the Eastern Caribbean (and thus groundwater resources) has changed in the past several thousand years as well as the causal mechanisms affecting these changes. This information is vital in understanding regional and global climate change, as well as managing the limited groundwater resources of Barbados and nearby islands in the face of future climate change scenarios.

Kendra L. Phelps ($2,000)
Ph.D. Candidate
Department of Biological Sciences
Texas Tech University

Conserving Cave Bats in the Philippines: Assessing the Impact of Cave Disturbance on Bat Communities

Abstract -The Philippines harbor a vast diversity of bat species, many of which are unique to the tropical archipelago. Nearly half of these bat species are dependent upon caves as roosting sites for rearing young and shelter from weather. Tragically, cave-dependent bats in the Philippines are threatened by human activities; this is particularly so on Bohol Island. Human pressures on cave bats are occurring at multiple scales on Bohol Island, including widespread landscape disturbances from illegal logging which results in the loss of foraging sites. Localized disturbances from residents, including hunting, cave tourism, and guano mining, add additional pressures. Such threats jeopardize the viability of cave-dependent bats. My study aims to compare cave-dependent bat communities among caves experiencing differing levels of human disturbance on Bohol Island to: i) assess the status of cave bats in an increasingly human-dominated landscape in order to identify priority caves; and ii) pinpoint threats that have the greatest impact on cave-dependent bats. Specifically, this study will quantify disturbance levels at 60 caves on Bohol Island using a modified karst disturbance index, and compare with species diversity and composition of cave bat communities documented over 2 consecutive nights. Results will be used to evaluate the significance of individual caves for maintaining viable populations of cave-dependent bats, identified as a priority under the Philippine National Caves and Cave Resources Management and Protection Act. Furthermore, assessing threats to cave-dependent bats allows for identification of the most detrimental forms of human activities, critical information for developing effective management strategies.