Jackson Blue is a first magnitude spring in the karst terrane of northeast Florida. Previous studies have identified inorganic fertilizer as the source of high nitrate levels in the spring. Agricultural land use and karst vulnerability make Jackson Blue a good model for conservation concerns. This work offers an aggregation of studies relating to the springshed, providing a valuable tool for planning and conservation efforts in the region. An analysis of nitrate levels and other water quality parameters within the springshed did not reveal significantly different values between agricultural and forested land use areas. Confounding factors include: high transmissivity in the aquifer, interspersed land use parcels, and fertilizer application in forested areas due to commercial pine stand activity.

Mangrove forests have one of the highest capacities of any ecosystem to sequester carbon. Mangroves in the Red Sea exist in a uniquely saline, high temperature, nutrient limited environment and the effects on carbon storage and greenhouse gas (GHG) emissions from arid mangrove soils is understudied. The flux of carbon dioxide (CO2) and methane (CH4) has the potential to enhance or reduce the carbon storage capacity of mangroves, which is an important nature-based solution for carbon drawdown to limit global warming. To determine the magnitude of CO2 and CH4 flux from mangrove soil in the Red Sea, soil cores were incubated on a monthly basis for over a year in light and dark conditions. Soil properties such as salinity, organic carbon, water content, bulk density, and stable isotopes, along with environmental variables such as inundation frequency and temperature were measured to resolve the drivers and variation of GHG flux over time. Additionally, 16S and 18S rRNA metabarcoding was conducted to determine the relative influence of prokaryotes and eukaryotes in the microbial mat within this mangrove ecosystem, and the microbial contribution to GHG flux. Oxygen microsensors were used for fine-scale resolution of the microbial mat, to determine photosynthetic rates and oxygen profiles. Fluxes were found to be highly variable, with the highest correlation between GHG flux and soil water content (p<0.05). Both prokaryotic and eukaryotic components of the microbial mat had a significant relationship with GHG flux, with mixed impacts depending on the taxa. These findings show that Red Sea mangroves, despite their lower carbon storage capacity, are a negligible source of GHG to the atmosphere unlike other regions where GHG emissions offset a greater proportion of carbon storage potential. Additionally, the importance of the microbial mat in this ecosystem is demonstrated, and an important consideration for future studies on mangroves and their potential as a nature-based solution against global warming.

No description available.

Thesis (M.S.)--University of North Carolina at Wilmington, 2004. / Includes bibliographical references (leaves : [38]-[40]).

Thesis (Ph.D.)--University of North Carolina Wilmington, 2009. / Title from PDF title page (January 12, 2010) Includes bibliographical references.

Ground-water geology along the northwest foot of the Blue Ridge between Arnold Valley and Elkton, Virginia The area discussed in this report lies along the northwest flank of the Blue Ridge in Rockbridge, Augusta, and Rockingham counties, Virginia. It spans the boundary between the Blue Ridge and the Great Valley physiographic provinces. The southeastern (Blue Ridge) portion of the area is mountainous and underlain by Precambrian crystalline and lower Cambrian elastic rocks. It is a major water catchment area for the eastern edge of the Shenandoah Valley and is chiefly a National Forest preserve. Cambriancarbonate rocks and fine-grained elastics underlie the relatively level areas between the mountains and the major subsequent streams near their base. A thick unconsolidated mantle which slopes gently away from the mountains conceals bedrock over much of the area. Major well fields have been developed on level alluvial floodplains and terraces adjacent to the rivers. Some produce several million gallons of water each day from bedrock aquifers at depth of from 50 to over 700 feet. The average temperature within the area is about 55°F. Average annual precipitation is approximately 41 inches and is greatest in the mountains. About six inches becomes ground-water recharge. Artificial withdrawal by wells would increase the rate of recharge. Evapotranspiration frequently exceeds total precipitation during the summer and early autumn. Most streams which drain the Blue Ridge are perennial near the headwaters and intermittent northwest of the mountains. They may be influent to bedrock aquifers within or near the base of the mountains and near the confluence with subsequent streams where the clay mantle is deeply eroded, but are effluent in the intervening reaches. The perennial streams are dominantly effluent. The major rivers are sub•sequent and effluent. They receive surface drainage and overflow of ground-water reservoirs from the Blue Ridge and from dominantly carbonate terranes to the west and northwest. Streamflow of the major streams represents approximately one third of the average annual areal precipitation. The stratigraphic sequence within the area from older to younger is designated as fellows: Precambrian crystalline rocks; Precambrian-Lower Cambrian Catoctin Greenstone and Swift Run Formations; LowerCambrian elastics; Lower Cambrian Tomstown (Shady) Delomite; Lower Cambrian Waynesboro (Rome) Formation; Middle Cambrian Elbrook Formation; and the Upper Cambrian Conococheague Limestone. The Precambrian igneous and metamorphic rocks, and the lower portion of the Lower Cambrian elastics are normally relatively poor aquifers. Minor production is obtained from fractured zones at locations within the mountains. The Antietam formation, the upper portion of the Lower Cambrianelastics, is a major potential aquifer. One well in Buena Vista produces over 600 gpm of water of low mineralization. Similar sites abound along the base of the Blue Ridge. The Tomstown Dolomite is a major aquifer at Waynesboro where the DuPont well field produces over 11,000,000 gpd. The producing characteristics of the Tomstown formation near the mountains at locations remote from the major rivers, where it is commonly concealed by a thick impermeable mantle of clay, are virtually unknown. Thick beds of limestone and dolomite in the Waynesboro Formationare prolific aquifers at Glasgow and near Elkton. Argillaceous portions of the formation are commonly aquicludes although secondary permeability may be developed by fracturing. Several wells produce over 1000 gpm from aquifers in the Elbrookand Conococheague formations near Grottoes and south of Elkton. With some exceptions, the water produced from these formations is harder than that produced from older formations to the east. A mantle of Cenozoic gravel and clay up to 400 feet thick overlies the bedrock over wide areas. The lower portion consists primarily of silty clay which is largely residual. Near the base of the mountains where it is thickest. it consists largely of leached colluvial material derived from the adjacent formations. It is characteristically an aquiclude which inhibits direct downward percolation of water to the underlying bedrock. Water encountered in the bedrock below it is commonly under mild artesian head. The upper portion of the mantle consists dominantly of alluvial and colluvial gravel with a sandy clay matrix and discontinuous beds of sand or of sandy or silty clay. It lies unconformably over residual clay and bedrock and is probably of Pleistocene age. It grades into talus near the foot of the mountains. The Cenozoic mantle yields only small amounts of water of variable quality to domestic wells although several large springs issue from it. The structural geology of the area is complex. Interpretation is complicated by facies changes and poor exposure. Fractures produced by deformation of the brittle rocks provide permeability. The main effect of the structure is its effect on the distribution of potential aquifers. The occurrence of ground water within the area is probably influenced more by topography, distribution of the unconsolidated mantle, and lithologic characteristics of the bedrock than by structure. Calcium and magnesium bicarbonate is the principal chemical constituents of ground water produced from major wells and springs within the area. Water from the carbonate aquifers is commonly moderately hard (61-120 ppm as CaC03). Nearly all of the hardness is temporary(carbonate) and is approximately equivalent to the alkalinity. Concentrations of deleterious substances are low. Water from the elastic rocks is characterized of low mineralization and pH. It is corrosive to ferrous metals. The temperature of well waters varies from 12° to 15°c. (54° - 59°F.)with few exceptions. Quality of ground water can commonly be correlated with the geologic formation from which it is produced. The concentration of total dissolved solids in waters from the bedrock aquifers tends to increase with decreasing age of the aquifer and with distance from the mountains. Water from limestone is commonly more highly mineralized than that from dolomite. Waters from. the same formation tends to be more highly mineralized west of the major rivers than they are to the east. Mineralization of most of the waters studied is derived from the dissolution of the carbonate aquifers and is controlled by equilibrium relations between dolomite, calcite, and dissolved carbon dioxide. The degree of saturation of waters with respect to solid calcite and dolomite can be determined semiquantitatively by comparison of the equilibrium pH computed from water analyses with the measured pH. Waters from typical dolomite reservoirs are supersaturated with respect to dolomite. The ratio of the concentration of calcium to the concentration of magnesium of most samples reflects the composition of the reservoir rock. Most samples contain more calcium than magnesium. Relationships between the calcium-magnesium ratio, the total mineralization, and the degree of saturation of water samples with respect to the solid carbonates are useful to relate the geology of the area to its hydrology. The quality of river water fluctuates widely with meteorologic variations, but that of ground-water produced from bedrock in adjacent wells east of the river remains relatively constant. Recharge to the wells at depth is evidently sufficient to prevent downward percolation of appreciable quantities of surface flow into the good bores although pumping levels are commonly below river level. The quality of the water suggests that recharge is dominantly from the east. Dolomite aquifers underlying floodplain and terrace deposits east of the major rivers are most favorable for the industrial development of ground-water resources. Prospective areas are outlined. Wells located in minor stream valleys near the boundary between the Blue Ridge and the Valley also offers prospects of production from Antietam or Tomstownaquifers. Test-drilling is warranted. Drilling of test wells should be the first step of industrial site investigation. The location of wells should be based upon a detailed local surface geological investigation. / Doctor of Philosophy

No description available.

Great Blue Herons (Ardea herodias) breeding near a pulp mill at Crofton B.C. failed to raise young in 1987 and 1988. Elevated levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzo-furans were detected in their eggs. The highest 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) toxic equivalent level observed was 496 ng/kg (wet weight) in 1987 (Elliott et al. 1989). I compared the Crofton colony with a less contaminated colony on Sidney Island in 1988 and 1989. I examined three possible explanations for nesting failure: (i) abnormal nesting behaviour by parents because of contamination, (ii) disturbance by human activities, and (iii) predation by Bald Eagles (Haliaeetus leucocephalus), Northwestern Crows (Corvus caurinus) and Common Ravens (Corvus corax). The Crofton colony was successful in 1989 and 1990. Within the TCDD toxic equivalent range of 34 - 257 ng/kg (1989), I observed no abnormal heron nesting behaviour or reduction in numbers of chicks fledged. In 1988 the herons at Crofton were disturbed repeatedly by human activities. Bald Eagles were observed daily at both Crofton and Sidney Island. The heron colony on Sidney Island failed in 1989 and 1990. The failures on Sidney Island were thought to involve a disturbance by eagles followed by rapid removal of eggs and young chicks at unattended nests by crows and ravens. It is likely that disturbance and predation played a part in the failure at Crofton in 1988, but there remains the possibility that environmental contaminants may have increased the sensitivity of herons to disturbance and predation. / Land and Food Systems, Faculty of / Graduate

One person - one vote; on Election Day in a representative democracy, everyone with the right to vote is equal. However, this occurs in Sweden once every four years. Between those occasions, we cannot be certain that political influence is equal until this has been tested. In this thesis, I will investigate whether Swedish democracy is responding to blue- and white-collar families equally. Do they have equal influence over public policy? And what consequences do the result have for some theories of democracy? With quantitative research, by replicating large parts of the research done by Martin Gilens and his research team, this thesis will be able to test if political influence is equal between these two groups. This allows us to test some of the theories and earlier research conclusions of Swedish democracy. No one, that I am aware of, has published something regarding this type of research in Sweden before. Gilens &amp; Page’s (2014) research found that in the United States, economic elites and interest groups had substantial influence on public policy whereas average citizens had little or none - confirming economic elite domination and biased pluralism theories. By analysing 182 policy proposals, I find no clear proof, but strong indications that white- collar families have more influence on policy-making than blue-collar families. Future research would most likely be able to draw more confident conclusions if there was a greater data sample. If these indications are correct, then this has implications for some theories of American and Swedish democracy.

Destination USA examines the works of the travel writer William Least Heat-Moon and his place ·in the tradition of American travel writing. The study begins with an overview of the current scholarship and trends within contemporary American travel writing and then moves on to limit and to define its scope. Next an outline and an in-depth explanation of the structure and thematics of such works is presented. Contemporary American travel writing has two dominant structures: the on-the~road motif and the intimate journey Of~ place. Woven into these two structures are three main themes common to both. The first theme focuses on the role of selfdiscovery in travel writing. The second theme highlights the role of travel writing in discovering hidden or marginalised American voices. The third theme centres around travel writing's use as a warning about or an assessment of the current American situation. Next a historical overview of the roots of American travel writing is undertaken which highlights the role it has played in the foundation of the country as well as providing the basis for those structures and themes outlined above. From there the dissertation moves onto an analysis of the works of William Least Heat-Moon: Blue Highways (1982), PrairyErth (1991) and River-Horse (1999). Heat-Moan's works provide an effective focal point for the understanding of contemporary American travel writing as a whole. They are forward looking and experimental while retaining a continuity with the tradition of American travel writing. An in-depth analysis of his trilogy on the American landscape is supported by previously unpublished interviews by the author. His works are then examined to uncover how they point to travel writing's elision with naturalist prose and work together to form a multifaceted vision of America. !