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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Measuring Conservation Success: An Investigation of Land Trusts in North Carolina

Alexander, Louise Boatwright 02 April 2010 (has links)
Local land trusts in North Carolina protect land to conserve natural resources and biodiversity, and to provide public benefits, such as clean air and water. However the success of their efforts is commonly reported in terms of the amount of land protected or money raised in support of conservation rather than in measures that describe whether or not conservations goals have been achieved. In order to determine if the conservation lands protected by local land trusts are meeting the goals they were intended to serve, I reviewed published research, literature and methodologies to identify common practices used to measure conservation success. Findings indicate three fundamental processes that allow organizations to evaluate the effectiveness of their interventions which are; 1) conducting status assessments that include articulating specific goals and describing the project context; 2) identifying threats to conservation targets; and 3) identifying, developing, and monitoring specific indicators whose status is a measurable reflection of the conservation targets and interventions. I also surveyed 24 land trusts in North Carolina to determine why they protect lands, what activities they perform that would allow them to evaluate the conservation impact of their work, and how success is reported to the public. From the survey, I conclude that land trusts in North Carolina are unable to determine if the lands they have protected are meeting their conservation goals because they are not consistently setting measurable goals, indentifying specific conservation targets, or monitoring indicators that would reflect conservation impact, processes identified in the literature review as necessary to evaluate conservation projects. I identify the Open Standards for the Practice of Conservation framework as an applicable tool for local land trusts to use to focus their conservation efforts and develop measurable goals and report their conservation success.
12

Natural Variation of Hydrology in Nonrivierine Wet Hardwood Forests and the Implications for Restoration

Johnson, Yari Ben 15 January 2010 (has links)
Wetland restoration projects across the United States are failing. Restored sites commonly lack the species and hydrology of the targeted community being restored. A better understanding of natural wetlands would help restoration project designers achieve community composition and hydrologic regimes that more closely resemble natural conditions. I investigated two different methods to identify patterns in hydrologic regime useful to restoration design. The first method was based on success criteria commonly used by North Carolina wetland mitigation projects. The second method was based on The Nature Conservancyâs Indicators of Hydrologic Alteration. In order to test these two methods, I collected hydrologic and compositional data across the natural variation of nonriverine wet hardwood forest stands, a rare wetland community type commonly restored in North Carolina. My results show that hydrologic parameters from the first method, based on current success criteria used in North Carolina, are not related to community composition. Hydrologic parameters from the second method, e.g. the maximum water table level over a 3-day span, explained much of the variation in nonriverine wet hardwood forest community composition. My results found that clear relationships do exist between hydrologic regime and community composition. Hydrologic parameters that are related to community composition need to be used as success criteria in future restoration designs. This will ensure that projects establish the appropriate hydrologic regime necessary to foster the desired wetland community type.
13

Understanding Environmentally Significant Behavior Among Guides in the Garhwal Himalaya

Serenari, Christopher 22 April 2010 (has links)
A gap currently exists in research pertaining to the utility of low impact outdoor ethics in non-Western societies. Many non-Western societies rely on their own religious beliefs, cultural perceptions, and traditions to serve as the foundation for conservation and environmental protection and influence related behavior. This notion also includes guides, who have been identified as effective in altering client behavior and minimizing environmentally destructive behavior. Exploratory research was conducted in Garhwal, Uttarakhand, India in 2009 applying the Theory of Planned Behavior to identify those cognitive factors that lead whitewater and trekking guides to pack out trash, bury human waste, and cut living trees for firewood. Results suggest that the foundational constructs of the Theory of Planned Behavior are capable of predicting intention to perform pro-environmental behavior in a non-Western population of guides; however, their utility depends on the behavior performed. The implications of these results are discussed.
14

Technology Adoption in West Africa: adoption and disadoption of soybeans on the Togo-Benin border

Jones, Kelly Michelle 26 April 2005 (has links)
New agricultural technologies are promoted in developing countries to bring about some combination of economic, environmental, and or health benefit. All of these benefits are considered to improve the livelihoods of the households that adopt them. However, the adoption of these new innovations by farm households is never uniform but is based on each household?s evaluation of the utility of the new technology with relation to that household?s attributes. This study looks at the adoption of a new agricultural crop?soybeans?that has been promoted for its nutritional effects in the Tamberma region of Benin and Togo. Variables affecting adoption and disadoption are based on five broad categories of adoption determinants found in the literature: household preferences, resource endowments, economic incentives, risk and uncertainty, and biophysical characteristics. A sixth category of farmer?s perceptions is added to this model to determine current perceptions of soybean utility in the study area. A Probit model is employed to determine factors affecting adoption and disadoption rates in the study area. Variables statistically correlated with the adoption decision include: education, extension, membership, health, cash cropping, and soil quality. Variables statistically correlated with the disadoption decision include: education, experience, expected price, and type of soil.
15

Geographic Modeling of El Niño Southern Oscillation Influence on Remotely Sensed Global Nutrient Distribution Patterns -- Applications to Science and Geographic Information Systems Education

Jason, Allyson Lynne 24 April 2002 (has links)
The objective of the study was to geographically model the effects of the El Niño Southern Oscillation (ENSO) influence on remotely sensed global nutrient distribution patterns. The result was a system of digital maps communicating the impact of ENSO on the physical and biological components of the ocean. These maps compare modeled phytoplankton biomass distribution over the ENSO extremes. Chlorophyll a, Aerosol Optical Thickness, and Sea Surface Temperature data, all obtained from remotely sensed sources, were used to develop these predictions. Areas of iron deposition and phytoplankton presence (chlorophyll a < 0.1 mg 1-1) were combined with nutrient distributions (based on the temperature-nutrient relationship) to create a sixteen-category composite phytoplankton ecological factor distribution map for each month in the study. The months included in the study were January, February, March of 1998, an El Niño year, and January, February, March of 1999, a La Niña year. Finally, an educational multimedia tool (CD-ROM) was created based on the research in the study for use in grades 7-16 classrooms. The tool was designed and tested to utilize Geographic Information Systems and the Internet to apply inquiry-based learning to science education.
16

The Relationship Between Past Experience and Multiple-use Trail Conflict

Bradsher, Debra J 10 June 2003 (has links)
The purpose of this study was to test the relationship between past experience in several trail activities and conflict due to encounters with trail users engaged in those activities. This research question involved the following trail activity groups: runners, walkers or hikers, mountain bikers, horseback riders, and users with dogs. Data were collected through on-site interviews with 421 trail users in the Greater Snow King Area of the Bridger-Teton National Forest near Jackson, Wyoming from July 17 to August 11, 2002. Conflict was assessed by asking participants to rate their increased/decreased enjoyment due to encounters with each of the other user groups. Past experience in an activity was determined by whether a participant had ever participated in that activity on any trail. In tests of the relationship between past experience in an activity and conflict due to encounters with participants of that activity, results indicated that two were statistically significant at the .05 level (running and walking dogs). Trail users who had participated in the activity in the past experienced less conflict when encountering that group than did respondents who had never done the activity before. Likewise, those who had participated in an activity in the past were more likely to experience increased enjoyment due to encounters with that group than were trail users who had never done the activity before. This pattern held for running, mountain biking, horseback riding, and dog walking although it was not significant at the .05 level in the cases of mountain biking and horseback riding. The relationship between past experience walking or hiking and conflict due to walkers or hikers could not be tested because only two respondents indicated that they had never walked or hiked on a trail. Trail users with past experience in an activity may have experienced less conflict when encountering that group because they better understood the requirements of the activity or because they saw the other users as having lifestyles, values, and/or attitudes similar to their own. Findings suggest that efforts to promote tolerance for other user groups may reduce the occurrence of conflict among trail users. Other implications for management and further research are discussed.
17

What factors influence freshwater molluscan survival in the Conasauga River?

Sharpe, Adam James 28 June 2005 (has links)
Recent biological inventory data shows a consistent decline in molluscan abundance and biodiversity in the Conasauga River Basin in Northwest GA. This study was initiated to monitor sediment and water quality by stable nitrogen isotope ratio analyses (IRMS) of snails and sediments, permeable membrane devices (PMD), polar organic chemical integrative samplers (POCISTM), and conventional water quality analyses for the Conasauga River Basin. Atrazine, metalochlor, prometon, and simazine were the most frequently detected herbicides throughout the basin. Most of the ambient concentrations of detected organic contaminants are at or near the method detection limit and all are well below any aquatic life criteria. Recent evaluation of water quality criteria for ammonia and nitrate suggest that these criteria levels are not protective for mussels. Data suggests that a shift to livestock and row crop land-use results in greater water nutrient levels and increased ä15N signatures for aquatic snails. Mean ä15N values for snails collected at national forest sites are significantly different from ä15N in snails collected in agricultural areas of the Conasauga River Basin (Student t-test, p<0.05). ä15N signatures of cow manure (6.71? wet, 8.40? dry) and poultry manure treated soil (9.47?) were similar to those of the snails collected in the agricultural areas of the Conasauga. Dissolved nitrate had elevated ä15N signatures that reflected the upper range of ä15N signatures for the aquatic snails. Elevated nitrogen isotope signatures indicate the fact that a shift in land use within in the basin is impacting the dominant nitrogen source to the aquatic environment. Continued evaluation of water quality criteria levels are needed to determine if aquatic habitats are viable for mussel reproduction, growth, and survival.
18

Modeling Soil Erosion and Sediment Transport from Fires in Forested Watersheds of the South Carolina Piedmont.

Crumbley, Tyler Autry 08 August 2007 (has links)
Forested watersheds in the Southeastern U.S. provide high quality water vital to ecosystem integrity and downstream aquatic resources. Excessive sediment from human activities in forested watersheds is of concern to responsible land managers. Prescribed fire is a common treatment applied to Southeastern Piedmont forests and is becoming increasingly important under the threat of higher fuel loads, and higher intensity storm events from changing land uses and climate. Several studies have been conducted to evaluate the impacts of fire on sedimentation processes with conflicting conclusions. Measuring the amount of runoff and erosion from fire-induced forested watersheds is difficult due to the high variability inherent in these systems. Erosion simulation models assist in relieving the time and resources consumed measuring these effects. The process-based Water Erosion Prediction Project (GeoWEPP) is widely used in the Western U.S. to predict erosion resulting from forest fires, but has yet to be tested in Southeastern Piedmont settings. The objective of this study was to evaluate the effectiveness of the GeoWEPP model in predicting sediment amounts from low-, moderate- and high-intensity forest fires on pine stands of the Sumter National Forest in the piedmont region of South Carolina. GeoWEPP simulation results were compared to observed sediment production from two ongoing prescribed burn studies in the Enoree and Long Cane Ranger Districts. Erosion measurements were conducted using 48 silt fences placed on hillslopes within 22 x 22 m plots. The measurements were collected biennially following low- and high-intensity prescribed burnings of the forested plots. The annual observed erosion amounts averaged 0.014 and 0.022-kg/m (width) for the Enoree and Long Cane sites respectively. Modeling results from the simulations of the same sites averaged 1.94-kg/m width of fence and 0.55-kg/m (width) annually. The model largely over predicted the amounts of erosion at these low levels. However, the average observed erosion amounts and average GeoWEPP predictions of 0.01 t/ac/yr were well below the tolerable soil loss value (T-value) of 0.41 t/ac/yr during the unburned, low-, and high-intensity forest fire conditions of the treatments. Predicted erosion exceeded this value only for high-intensity fires followed by high-intensity storm events (>20-yr return periods). These results suggest that low-intensity fires may not elevate sediment loading above tolerable rates; however, higher-severity fires can cause soil erosion and sediment loading at levels of concern in water quality degradation. Land topography, fire intensity and soil surface texture type are key variables to predicting soil erosion and runoff. We conclude that this model may be a useful tool to land managers for evaluating and predicting the effects of fire on erosion following forest fires. This study is the first to evaluate the effectiveness of the GeoWEPP model in predicting runoff and sedimentation in Southeastern piedmont watersheds. From this initial testing, recommendations were made to improve the model for applications in the Southeast.
19

Conifer Discrimination in the Sandhills of North Carolina Using High Spectral Resolution Data

Otwell, Dwight Woodard 12 August 2008 (has links)
We investigated techniques to discriminate long leaf pine (Pinus palustris) and loblolly pine (Pinus taeda) in 126 band HyMap imagery with a 4 meter spatial resolution. Field assessment provided stand composition information, and crowns of known species were selected in the imagery to represent species types for model construction. A Quadratic Discriminant Analysis used with a likelihood ratio test was able to identify southern yellow pine with a producerâs accuracy of 98% and a userâs accuracy of 96%. The same test identified loblolly pine with a producerâs accuracy of 80% and a userâs accuracy of 49%. Longleaf pine identification had a producerâs accuracy of 60% and a userâs accuracy of 76%. Price of image acquisition, the relatively low accuracy of discrimination between longleaf and loblolly pine crowns, and inherent bias in the approach make this particular method unreliable as an option for targeting potential sites for RCW habitat restoration.
20

The Effects of Culverts and Bridges on Stream Geomorphology

Merrill, MaximilIan Atlas 07 December 2005 (has links)
Culverts and bridges are necessary in order to cross waterways during road construction. However, these structures have detrimental affects on the hydrology and ecology of the streams they cross. The objective of this study was to investigate how these bridges and culverts alter stream hydrology and geomorphology by determining the effects on the upstream and downstream reaches of a road crossing on the cross sectional area, the hyporheic depth, on riffle habitat, and substrate types. Three types of culverts (arch, box, and pipe) and small bridges were evaluated. All four types of stream crossings were determined to increase the cross sectional area downstream of the structure. Crossing structures also affected hyporheic zone depths by decreasing average depths downstream of the structure. Finally, most mussels seemed to occur in substrates that were dominated by relatively large particles (gravel and cobble) that were less movable by sheer stress during higher flows. Each of the problems discovered with these structures is a result of the channel restriction and the increased flow velocity and turbulence scour that it creates. These detrimental conditions can be mitigated by providing for floodplain access for higher flows. It is recommended that culverts be designed for low flows and high flows. Oversizing culverts, compared to current design criteria will allow floodplain access and build bankfull benches in the extra openings to restrict low flows to a few openings. The use of bridges that span across the valley limiting fill and allowing floodplain access may even be more beneficial. When valley fill is necessary, then side culverts in the floodplain may alleviate degradation and allow more natural floodplain hydrology.

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