Regional paleoclimatic proxies and current local climate variables and were analyzed to reconstruct paleoglaciers in an effort to assess glacier change On Mount Rainier. Despite the dry and generally warm conditions (sea surface temperatures (SST) -0.15°C to +1.8°C relative to current temperatures), the previously documented McNeeley II advance (10,900 - 9,950 cal yr B.P.) was likely produced by air temperature fluctuations. The average SST record and the terrestrial climate proxies show cooling temperatures with continued dryness between McNeeley II and the Burroughs Mountain advance (3,442 - 2,153 cal yr B.P.). The paleoclimate during the Burroughs Mountain advance was both cool and warm (SST temperatures -0.55°C to +0.5°C) and was the wettest of the Holocene. A combination of statistical and deterministic equilibrium line altitude (ELA) models was used to produce Holocene ELAs between 1,735 -2,980 m. Glacial advances were predicted 10,990, 10,170, 9,260, 8,200, 6,490, 3,450 and 550 - 160 cal yr. B.P. Two glacier flow models were produced simultaneously to constrain glacial extent through the Holocene. Model I is based on current mass balance parameters and produced lengths for the Nisqually and Emmons glaciers 3.7 - 14.2 km and 4.2 - 17.1 km respectively. Glaciated area ranged from 26 to 327 km2. Model 2 is tuned to the Garda advance and produced lengths 2.6-10.6 km and 2.3-13.9 km. Glaciated area ranged from 11 to 303 km2. The first two advances were similar in elevation and GIS-modeled extent to McNeely II moraines. The following three advances were not detected in the geologic record. The 3,450 cal yr. B.P. advance was the largest of the late-Holocene (ELA 1,800 - 1,817 m) and was ~200 m lower than the geologic record. The ELAs of the Garda advance were modeled (1,944 - 1,983 m) and are similar to previous reconstructions. North-south spatial variations in glacial extent increase during periods of recession as the southern glaciers receive more ablation than northern glaciers. Early humans could have accessed the alpine environments as high as 1,730-2,980 m. The early Holocene glacial extent allowed the highest (2,980 m) 11,150 cal yr. B.P. and lowest (1,730 m) 10,990 cal yr. B.P. alpine access. Glacial retreat (2,727 m 10,400 cal yr. B.P.) was followed by an advance (1,929 m 10,170 cal yr. B.P.) and another retreat (2,951 m 10,050 cal yr. B.P.). Ice gradually descended and limited access to 1,820 m 6,490 cal yr. B.P. Glacial extents remained largely unchanged until the historic era when paleohumans would have had access to alpine environments at 2,000 m.

The aim of this thesis is to understand spatiotemporal temperature variability in southern South America by identifying overarching temperature variability states and their associated synoptic-scale meteorological patterns. Further, the temporal frequency of occurrence of those temperature variability states is investigated as is the role of recurrent low-frequency modes of climate variability (El Niño Southern Oscillation and the Southern Annular Mode) on temperature variability. K-means cluster analysis is used to group all months during the period 1980-2015 into four primary categories for summer and winter separately. Monthly maps of temperature anomalies are provided as input to the k-means algorithm and the resulting temperature variability states are the composites of temperature anomaly maps for months assigned to each cluster, illustrating the primary spatial patterns of temperature variability over Southern South America. Composites of synoptic-scale meteorological patterns (wind, geopotential height, and moisture fields) are calculated for months assigned to each cluster to better diagnose the driving meteorology associated with these patterns of temperature variability. Results show that in summer surface wind direction and geopotential height are robust indicators of temperature variability patterns, while in winter jet stream winds are important for diagnosing equatorward excursions of cold air and poleward excursions of warm air. According to the results the El Niño Southern Oscillation and the Southern Annular Mode exhibit some relationship with temperature variability state frequency, with some states more associated with these two modes than others, however they do not appear to be primary drivers of any of the temperature variability states.

Animal home range estimations are important for conservation planning and protecting the habitat of threatened species. The accuracy of home range calculations is influenced by the map projection chosen in a geographic information system (GIS) for data analysis. Different methods of projection will distort spatial data in different ways, so it is important to choose a projection that meets the needs of the research. The large number of projections in use today and the lack of distortion comparison between the various types make selecting the most appropriate projection a difficult decision. The purpose of this study is to quantify and compare the amount of area distortion in animal home range estimations when projected into a number of projected coordinate systems in order to understand how the chosen projection influences analysis. The objectives of this research are accomplished by analyzing the tracking data of four species from different regions in North and South America. The home range of each individual from the four species datasets is calculated using the Characteristic Hull Polygon method for home range estimation and then projected into eight projected coordinate systems of various scales and projection type, including equal area, conformal, equidistant, and compromise projections. A continental Albers Equal Area projection is then used as a baseline area for the calculation of a distortion measurement ratio and magnitude of distortion statistic. The distortion measurement ratio and magnitude calculations provide a measurement of the quantity of area distortion caused by a projection. Results show the amount distortion associated with each type of projection method and how the amount of distortion changes for a projection based on geographic location. These findings show how the choice of map projection can have a large influence on data analysis and illustrate the importance of using an appropriate PCS for the needs of a given study. Distorted perceptions can influence decision-making, so it is important to recognize how a map projection can influence the analysis and interpretation of spatial data.

Emerald Pond (26° 32' 12" N, 77° 06' 32" W) is a vertical-walled solution hole in the pine rocklands of Great Abaco Island, The Bahamas. In 2006, Sally Horn, Ken Orvis, and students recovered an 8.7 m-long sediment core from the center of the pond using a Colinvaux-Vohnout locking piston corer. AMS radiocarbon dates on macrofossils are in stratigraphic order and indicate that the sequence extends to ca. 8400 cal yr BP. Basal deposits consist of aeolian sands topped by a soil and then pond sediment, suggesting that the site began as a sheltered, dry hole during a Late Pleistocene low sea level stand, and became moister as climate changed and rising sea level pushed up the freshwater table. The limestone rockland surrounding the site is presently dominated by Bahamian pine (Pinus caribaea Morelet var. bahamensis (Griseb.) W.H. Barrett & Golfari) with an understory of hardwoods and several palm species. Pollen analyses on the sediments of Emerald Pond indicate significant environmental change at the site. Pines and palms have dominated for much of the record, with some variation in relative importance. Pine pollen shows a non-uniform, general increase over the record, with highest values reached in a section of the upper meter of the record that contains abundant microscopic charcoal that may be related to anthropogenic activities. Palm pollen is well represented in all but this upper section of the core. The shifts in pollen percentages in the upper meter of the core suggest a generally drier environment during the last two millennia at Emerald Pond.

The Ecuadorian páramo is characterized by unique soil properties that allow the ground to hold large amounts of water. These páramo grasslands support Andean cities and communities as a source of water for municipal, industrial, and agricultural use. Although recent research has suggested that changes in land use can decrease the amount of water and affect the water-holding capabilities of the soil, the hydrologic effects of different land uses, including burning for livestock grazing and pine planting for carbon credits, are currently under debate. This research tested hypotheses about moisture-related properties of páramo soils under different land uses at two study areas in Ecuador. Bulk density, volumetric water content, water retention, and general physical properties were identified and compared between sites at those study areas. Soil structure differed between pine sites and other sites at both study areas, and moisture consistency differed between pine and other sites at the Mazar Wildlife Reserve. Volumetric water content values were high (mean of 86% at one Mazar site) but the pine sites contained less water by volume than the other sites. Water retention data showed that the surface horizons of all sites at both study areas require more pressure to release moisture than the subsurface horizons. Compared to other sites studied, the pine sites from both study areas have lower gravimetric water contents at saturation through -6.0 kPa. Different burning regimes do not appear to affect soil properties, in-situ moisture content, or water-retention capacity. The introduction of pine plantations in the páramo at both study areas appears to have lowered soil moisture contents and reduced bulk density in the soil profile. This research adds to a growing group of studies that show that changes in land management can affect the hydrological properties of soils.

South-central Kentucky has one of the world’s most intensively studied karstareas, with most work focusing on the Mammoth Cave System and related caves and aquifers. However, slightly higher in the stratigraphic section than Mammoth Cave, the Haney Limestone is a locally important but less well studied carbonate aquifer. This research provides the most comprehensive synthesis to date of the karst hydrogeology of the Haney Limestone of south-central Kentucky, focusing on the distribution and controls on cave and karst features developed within. In contrast to drainage systems within the major limestones below, joints are the most dominant control on passage development in the Haney Limestone within the study area and the orientation of these joints is consistent with that of regional joint sets. Bedding planes and the presence of insoluble rock at the base of the Haney also exert control on conduit development in the Haney Limestone. Most of the caves of the study area developed in the Haney Limestone are singleconduit caves that receive water through direct, allogenic sources. Cave entrances are frequently perennial spring resurgences and the presence of active streams suggests that the caves function within the contemporary landscape, acting as drains for localized recharge areas. The hydrology of the Haney Limestone plays an important, if localized, role in the regional hydrology of south-central Kentucky, integrated into the current system of surface and subsurface drainage of the regional karst landscape. Evidence supports the idea that caves of the Haney Limestone are, geologically, relatively recent phenomena. A majority of the cave passages in the study area are hydrologically active, the water resurging from the sampled springs is typically undersaturated with respect to limestone, and the caves in some case appear to be developed along potential stress release fractures associated with small, apparently young valleys. This suggests that caves in the Haney Limestone were not directly influenced by the incision of the Green River over vast periods, like Mammoth Cave, but that cave development is a largely contemporary process.

The groundwater in agricultural karst areas is susceptible to contamination from organic soil amendments and pesticides. During major storm events during 2011, dye traces were initiated using sulphorhodamine-B, fluorescein and eosine in a groundwater recharge area where manure was applied to the ground. Fecal coliform samples were collected from significant storm events from January-September 2011. Water samples and geochemical data were collected every four hours before, during, and between the storm events from a waterfall in Crumps cave flowing from the known recharge area to track the transport and residence time of the epikarst water and organic soil amendments during variable flow conditions. Two dataloggers at the same waterfall were set up to collect 10-minute data, which included pH, specific conductivity, temperature, and discharge. Total rainfall amount and other surface meteorological data were collected from a rain station located above the cave. Cave water samples were collected for the analysis of anions, cations, bacterial count, and the presence of dye. The dye traces show variability in the characteristics of epikarstic response and flowpaths. The changes in geochemistry indicate simultaneous storage and transport of meteoric water through epikarst pathways into the cave, with rapid transport of bacteria occurring through the conduits that bypass storage. Fecal coliform counts were elevated all through the study period indicating survivability in soils through the seasons. The results indicate that significant precipitation events affect the storage properties and rapidly impact the various pathways and timing of contaminant transport through the epikarst zone, eventually allowing these contaminants to be transported unfiltered in to the groundwater supply. This study shows that current best management practices in karst lands need to be revisited to incorporate areas that do not have surface runoff but where contaminants are transported by seepage into local aquifer.

Ostracodes, bi-valved crustaceans, are potentially excellent proxies for salinity.They are abundant, react to changes in salinity, and secrete low-magnesium calcite shells that preserve information about their host water chemistry. Changes in valve trace element concentration, stable isotope composition, and sieve pore shape values have been linked to changes in salinity. This study analyzed the response of the euryhaline ostracode, Cyprideis americana, to salinity in six lakes from two Bahamian islands across two seasons. The purpose of this work was to determine which compositional and morphological variables in C. americana are the most useful for paleosalinity reconstructions.Ostracode and water samples were collected from lakes of varying water chemistry on San Salvador Island (winter and summer seasons), and Exuma (winter season). Dissolved oxygen, pH, salinity, and temperature measurements were taken for each lake. The best-preserved valves from each lake were analyzed for sieve pore circularity, Mg and Ca concentrations, and δ18 O isotopic composition. Mg/Ca ratios and Kd[Mg] values were calculated for each lake. Each parameter was plotted against salinity for all of the lakes and for lakes from each season and island. Only the samples collected during the summer followed expected trends: with increases in lake water salinity, Mg/Ca ratio decreased, δ18 O composition increased, and sieve pore circularity decreased. Samples collected from the winter field sessions did not follow expected trends, potentially due to the breeding and moulting habits of C. americana. Temperature was more correlative with valve composition than a previous study of C. americana suggests, but is supportive of similar correlations of Cyprideis species in continental and other island settings. The valve Mg/Ca ratio and mean sieve pore circularity showed the best correlation with salinity and are the variables that will be most useful in paleosalinity studies from sediment cores. Future work should further investigate the relationship between mean sieve pore circularity and lake salinity as well as the breeding and moulting habits of C. americana. Such work may allow for past salinity ranges to be reconstructed from fossil C. americana samples.

ABSTRACT Karst regions of the world that receive relatively similar amounts of precipitation display a wide variety of landscapes. It has been suggested (Groves and Meiman, 2005) that climates exhibiting larger discrete storm events have more dissolving power and consequently higher rates of conduit growth than climates with more uniform precipitation distributions. To study this concept, a computer program “Cave Growth” was developed that modeled the growth of a cross-section of a cave passage under dynamic flow and chemical conditions. A series of 46 simulation datasets were created to represent different climatic conditions. These simulations had the same total annual discharge, but demonstrated a range of flow distributions quantified by use of a gamma distribution index, along with two special theoretical cases. After simulating a year of conduit growth for each of the various flow distributions in a series of model runs, and repeating these sets of simulations for three different passage cross-section geometries, it was evident that the annual temporal distribution of flow did indeed impact the amount of cave growth. However, an increase in the “storminess” of the climate did not simply equate to more dissolution and thus conduit growth. Rather, the quantity and duration of surface contact between water and the conduit walls combined with dissolution rates to affect the total growth. The amount of wetted perimeter (contact between fluid and passage floor/walls) generated by specific conduit to capacity were shown to be very effective at growing the cave. Above this level, the dissolving power of additional water was essentially wasted. This investigation suggests that the maximum amount of passage flow levels depended upon the shape of the passage. Flow conditions that filled the growth occurs under flow conditions that result in the most wetted perimeter for the longest period of time at the highest dissolution rate.

Karst regions are composed of soluble rock, often limestone, which leads to the formation of fissures, sinkholes and water flow conduits such as caves. Pollutants in karst waters tend to be quickly directed and concentrated into these subsurface conduits. As a result of this and other factors, water resources are especially sensitive to contamination and pollution in karst areas. Pollutant concentrations going into fluvial systems travelling through the subsurface in karst areas are often very similar to the concentrations arriving at outlets such as springs. Areas connected by karst conduit flows must be distinctly determined and special attention should be given to water quality impacts from land-use practices near conduit inputs. The climate which affects a certain karst area can also have different impacts on water resources considerations. For example, in the temperate climate of Kentucky precipitation is essentially even in distribution throughout the year. In contrast, southwest China is affected by a monsoon climate with high precipitation in the spring to summer and drier conditions in other seasons. In the wet season large storm pulses can effectively transport contaminants to water sources resulting in loads that can be unhealthy for frequent human consumption in drinking water. The dry seasons can be particularly severe in karst areas as water quickly drains to the subsurface, making water access a major hardship. The research for this study focused on the seasonal influences that the climate of southwest China poses for water quality, including differences in pesticide concentrations between agricultural and residential areas hydrologically linked by karst conduits. In late 2007 the fluvial connections in a simple karst system near Chongqing were confirmed using dye tracing techniques. Once these connections were established and the flow of the subterranean stream was assessed, the transport of agricultural runoff in the system was studied. Data loggers were used to record continuous data of the water conditions, including nitrate concentrations. The pesticides in the agricultural runoff entering and exiting the subterranean stream were quantified using ELISA methods. The concentrations were found to be within safe limits for drinking water. The hypothesis that there is a close relationship between concentrations of the pesticides glyphosate, chlorothalonil, and triazines in the input and the output of the system was supported by the results. When considering the hydrology and water chemistry data of the site, along with the water samples tested for pesticides, non-parametric statistical testing showed the correlations between these factors to be significant with p<0.01. The percent difference between the input and the output concentrations of glyphosate, chlorothalonil, and triazines were 31, 43, and 57% respectively. Taking into account the rapid and direct flows in this karst system, the concentrations of the pesticides found in the output were more similar to the input than would be expected in a surface stream. This suggests that there are fewer natural remediation effects reducing contamination in subsurface karst rivers of southwest China than in surface rivers. Therefore, these systems should be handled with extra attention to possible contamination of water resources. The research was conducted in the spring and summer of 2007-2008 and funded by the U.S. Agency for International Development.