The Bouteloua curtipendula (Michx.) Torr. complex (BCC) is composed of 11 species and five varieties distributed in North and South America with its center of diversity in Mexico. It is characterized by tremendous morphological variation and taxonomic complexity that is most likely due to reticulate evolution, phenotypic plasticity, and the development of asexual reproduction (apomixis). Climate-induced range changes over evolutionary time may explain the origin of the morphologically diverse BCC as suites of species came into contact over time, hybridized, and created new species, cytotypes, and reproductive modes. I investigated the origins of the BCC by creating habitat suitability models based on present-day occurrence records for eight BCC taxa and hindcast these models to paleoclimate reconstructions for the Last Glacial Maximum and Last Interglacial. By estimating range dynamics over time, coupled with phylogenetic data, I inferred the locations of contact zones among taxa and identified likely progenitor taxa for various cytotypes found in the BCC. Species with large and environmentally heterogeneous distributions may have large ranges due to plastic responses to environmental variation for adaptive traits or they may maintain differently adapted ecotypes to specific habitats. I evaluated phenotypic plasticity for stolon and rhizome production in the three taxonomic varieties of B. curtipendula. My results indicate that expression of these traits is correlated with specific, local environmental conditions and not to broadly defined environments in geographic space and that phenotypic plasticity accounts for a greater proportion of trait expression than does total genetic variance. Apomixis, asexual reproduction via seed, most likely results from interploidy hybridization. There are many possible pathways that lead to asexual seed formation and understanding these pathways is important to understanding genetic diversity, demography, and evolutionary potential in apomictic and mixed apomictic-sexual populations. I discovered that B. curtipendula var. caespitosa, the only recognized apomictic taxon in the BCC, is pseudogamous, indicating that although fertilization is unnecessary to produce the embryo, it is necessary to produce the endosperm. These data also indicate that meiosis is highly irregular and results in sperm nuclei with variable chromosome numbers, which affects endosperm production, fertility and demographics in apomictic B. curtipendula.

Four innovations in the fields of optical design and solar concentration are presented: a) the derivation of fundamentally new gradient-index (GRIN) distributions for perfect optical instruments. For the first time, GRIN lenses for visible and solar radiation with refractive index distributions that are amenable to current fabrication techniques are presented. Those lenses perform at nature's cardinal limits (within the geometrical optics approximation - valid for essentially all solar applications), i.e. perfect imaging and ideal nonimaging performance for monochromatic radiation and unprecedented image fidelity and near-ideal flux concentration for the full solar spectrum. Until now, there have been no GRIN solutions (for performance approaching the fundamental limits of flux concentration and image fidelity) that can accommodate an extended constant-index core - especially relevant because the only available fabrication techniques for visible and solar GRIN lenses require a constant-index core. b) The design, for the first time, of a nominally stationary solar concentrator with attainable geometric concentration of the order of 10super suns with high collection efficiency. The burden of tracking is transferred inside the stationary module where mm-scale motion of GRIN perfect imaging lenses tracks the sun. This creates the possibility for rooftop Concentrator Photovoltaics (CPV) with unprecedented optical performance and exceptional optical tolerance. c) The design of a nominally stationary solar concentrator with a modified Simultaneous Multiple Surface technique for nonimaging contoured lenses with flux concentration of the order of tenths of suns. d) The design of planar GRIN lenses able to deliver flux concentrations close to the thermodynamic limit to Solar Concentration with a single, optical element, previously deemed unattainable and particularly suitable to dual-axis tracking CPV.

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In the effort to restore historic landscapes, it is necessary to first specify spatially explicit target vegetation communities. Previously, botanists or other local experts have used landscape and environmental factors, historical evidence, and evidence from remnant vegetation to define presettlement vegetation communities on the landscape. Once these communities are defined, they must be mapped in order to be truly understandable and useful. Efforts to map the location of these presettlement communities on a particular landscape are often laborious and time consuming. In this study, we discuss a rapid method for assessing the location of these vegetation communities using Geographic Information Systems (GIS) and the current science of fire behavior modeling. Fire behavior models are proven predictors of fire intensities across a landscape, considering vegetation, slope, aspect, wind, and weather. Our hypothesis was that these fire behavior models could be used to make inferences about presettlement vegetation community distributions in former frequent-fire landscapes. GIS software was used to find simple combinations of variables associated with vegetation distribution, including soil type, aspect, slope, and orientation to gradient winds. A conventional fire model (FlamMap) was then used to find areas that are distinctly fire sheltered. In a survey of 78 fire sheltered community sites visited on the study landscape, 91% of the areas were considered to be correctly identified based on the presence of remnant presettlement vegetation indicator species. Success in finding a single community as related to a specified range of fire behavior outputs suggests that there is potential for expanded utility of fire models in making inferences about vegetative distribution on the frequent-fire landscape. The fire model adds to the utility of the GIS by considering the effects of fire spread direction and variation in fuel moistures in conjunction with terrain variables. The resulting fire intensity outputs represent environmental effects on vegetation distribution that cannot be modeled solely with a GIS. A final presettlement vegetation layer was completed for the study site, located at Fort Bragg on the Southeastern coastal plain of North Carolina, and compared to a layer generated by an extensive 2-year study considered to be definitive. The results showed an overall map accuracy of 78 percent for the proposed procedure. This output may be used as a preliminary map that, in conjunction with ground-truthing, will shorten the process of mapping presettlement vegetation for use in the restoration of historic fire dependent communities.

The growth characteristics and habitat of the rare shrub Amorpha georgiana var. georgiana were studied by examining 19 documented groups of this Federal Species of Concern. These 19 groups occur along the Little River on the Fort Bragg Military Reservation in Cumberland, Hoke and Moore counties, North Carolina. Systematic field studies located and monitored the plants, and a modified version of the North Carolina Vegetation Survey protocol produced an inventory of surrounding plant communities. Results were used to modify knowledge of A. georgiana var. georgiana and correct errors in previous accounts: flowering commences in mid-April and ends in mid-May; seeds may persist on the plants until the following April; tree canopy densities range above 75 percent; and the plant inhabits transition zones on the dry side of wetland boundaries. A key to guide searches for the plant is presented along with recommendations for further research to resolve remaining questions about the protection status of Amorpha georgiana var. georgiana.

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.

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.

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.

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.

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.