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Power Laws, Discontinuities And Regional City Size Distributions, Ahjond S. Garmestan, Craig R. Allen, Colin M. Gallagher Jan 2008

Power Laws, Discontinuities And Regional City Size Distributions, Ahjond S. Garmestan, Craig R. Allen, Colin M. Gallagher

School of Natural Resources: Faculty Publications

Urban systems are manifestations of human adaptation to the natural environment. City size distributions are the expression of hierarchical processes acting upon urban systems. In this paper, we test the entire city size distributions for the southeastern and southwestern United States (1990), as well as the size classes in these regions for power law behavior. We interpret the differences in the size of the regional city size distributions as the manifestation of variable growth dynamics dependent upon city size. Size classics in the city size distributions are snapshots of stable states within urban systems in flux.


Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood Jan 2008

Equilibrium Sampling Used To Monitor Malodors In A Swine Waste Lagoon, Rezaul Mahmood

School of Natural Resources: Faculty Publications

No abstract provided.


The Application Of Lc-Ms Technologies For The Detection Of Triazine Herbicides In Water, Michael Cahill Jan 2008

The Application Of Lc-Ms Technologies For The Detection Of Triazine Herbicides In Water, Michael Cahill

Theses

The triazine herbicides, including, simazine (6-chloro-N,N’-diethyl-1,3,5-triazine-2,4- diamine), atrazine (2-chloro-4-ethylamino-6-isopropylamino-l,3,5-triazine) and cyanazine were developed as selective weed killers. Their design function is to disrupt the photosynthesis of broad-leafed plants. In the intensive production of grasses (e.g. wheat, cereals, etc.) broad-leafed plants growing in the grass production area are economically costly, competitors with the grasses for nutrients; their removal is facilitated by triazines herbicides and simazine and atrazine are the predominant compounds used. Significant amounts of triazine herbicides are consumed by the agricultural industry each year. However, due to the indiscriminate use of pesticides/herbicides, traces of herbicides have been found in run-off …


Treatment Of Industrial Wastewater Containing Active Pharmaceutical Ingredients With A Membrane Bioreactor, With The Aim Of Reducing Resource Consumption, Pádraig Colm Ó'Maolcatha Jan 2008

Treatment Of Industrial Wastewater Containing Active Pharmaceutical Ingredients With A Membrane Bioreactor, With The Aim Of Reducing Resource Consumption, Pádraig Colm Ó'Maolcatha

Theses

The biodegradation of a selected active pharmaceutical ingredient (API) during wastewater treatment in a membrane bioreactor (MBR) was examined experimentally. A comparison study was conducted by operating a conventional activated sludge (CAS) pilot plant in parallel to the MBR. The MBR was operated under varying conditions of pH (pH6 and pH8), MLSS (6g/L and l0g/L) and SRT (20 days and 30 days) according to a full factorial design of experiments. In the CAS, pH and SRT were altered as above but MLSS was maintained at 3-4g/L. Comparable average API removal results of 95.5% and 95.7% were obtained for the MBR …


Mycobacteriosis-Associated Mortality In Wild Striped Bass (Morone Saxatilis) From Chesapeake Bay, Usa, D. T. Gauthier, R. J. Latour, D. M. Heisey, C. F. Bonzek, J. Gartland, E. J. Burge, W. K. Vogelbein Jan 2008

Mycobacteriosis-Associated Mortality In Wild Striped Bass (Morone Saxatilis) From Chesapeake Bay, Usa, D. T. Gauthier, R. J. Latour, D. M. Heisey, C. F. Bonzek, J. Gartland, E. J. Burge, W. K. Vogelbein

Biological Sciences Faculty Publications

The striped bass (Morone saxatilis) is an economically and ecologically important finfish species along the Atlantic seaboard of the United States. Recent stock assessments in Chesapeake Bay (USA) indicate that non-fishing mortality in striped bass has increased since 1999, concomitant with very high (>50%) prevalence of visceral and dermal disease caused by Mycobacterium spp. Current fishery assessment models do not differentiate between disease and other components of non-fishing mortality (e. g., senescence, predation); therefore, disease impact on the striped bass population has not been established. Specific measurement of mortality associated with mycobacteriosis in wild striped bass is …


Life Cycle Analysis For The Cultivation And Combustion Of Miscanthus For Biofuel Compared With Natural Gas, Amanda Ashworth, Charles West, Michael Popp, Mireille Montrejaud-Vignoles, Caroline Sablayrolles, Gabrielle Benoit Jan 2008

Life Cycle Analysis For The Cultivation And Combustion Of Miscanthus For Biofuel Compared With Natural Gas, Amanda Ashworth, Charles West, Michael Popp, Mireille Montrejaud-Vignoles, Caroline Sablayrolles, Gabrielle Benoit

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

As negative environmental and economic impacts of fossil fuels have escalated, so has the importance of renewable bioenergy crops whose feedstocks are noncompetitive with food supplies. Compared with fossil fuels, use of lignocellulosic feedstocks offers potential for greenhouse gas reduction and highly positive net energy returns because of low input demand and high yields per unit of land area, thus making them advantageous for the emerging biofuel industry. The aim of this study was to simulate environmental impacts of producing a biofuel grass for combustion use based on the inventory of inputs and their effects on eutrophication of surface waters; …


Using Biosolids To Enhance Phytoremediation Of Oil-Contaminated Soil, Heather N. Markway, Duane C. Wolf, Kaaron J. Davis, Edward E. Gbur Jan 2008

Using Biosolids To Enhance Phytoremediation Of Oil-Contaminated Soil, Heather N. Markway, Duane C. Wolf, Kaaron J. Davis, Edward E. Gbur

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

While the plant rhizosphere and associated microbial processes have been shown to amplify the degradation rate of chemical residues in soils, phytoremediation can be a slow process. The objective of this greenhouse study was to determine if the addition of biosolids as an organic soil amendment would enhance growth of plants in oil-contaminated soil and thus potentially increase effectiveness of phytoremediation. Pearl millet (Pennisetum glaucum (L.) R. Br.) or sudangrass (Sorghum sudanense (Piper) Stapf (Piper)) was grown in a Captina silt loam (finesilty, siliceous, mesic Typic Fragiudults) contaminated with 5% crude oil (v/w) and amended with 24 g biosolids/kg soil. …


Toward A New Consciousness: Values To Sustain Human And Natural Communities, Anthony A. Leiserowitz, Lisa O. Fernandez Jan 2008

Toward A New Consciousness: Values To Sustain Human And Natural Communities, Anthony A. Leiserowitz, Lisa O. Fernandez

Yale School of the Environment Publications Series

A Synthesis of Insights and Recommendations from the 2007 Yale F&ES Conference


Agricultural Systems: Agroecology And Rural Innovations For Development [Book Review], Charles A. Francis Jan 2008

Agricultural Systems: Agroecology And Rural Innovations For Development [Book Review], Charles A. Francis

Department of Agronomy and Horticulture: Faculty Publications

To welcome yet another book on sustainable development, a reviewer must look for what is unique and what adds value to the volumes already published. In Agricultural Systems, editors Sieglinde Snapp and Barry Pound have assembled a collection of chapters that goes beyond the usual praise and criticism of the green revolution and the focus on economic development. Their book provides a first-hand story by people with lengthy experiences in the field, especially in Africa, who have developed and tested grassroots, participatory development approaches. The result is a valuable set of principles, strategies and case studies that paint a new …


Influence Of Row Spacing And Debris Distribution On Vegetation And Small Mammals In Louisiana Pine Plantations, Anne M. Bechard Jan 2008

Influence Of Row Spacing And Debris Distribution On Vegetation And Small Mammals In Louisiana Pine Plantations, Anne M. Bechard

LSU Master's Theses

Site preparation after clearcuts directly affects surrounding small mammal populations. Differences in bed row spacing and arrangement of debris can impact structure and composition of vegetation communities, which influence small mammal habitat. We surveyed vegetation and small mammals in 2 different row spacings (14 ft and 20 ft) and 2 different debris distributions (piled and scattered) in 4 clearcuts owned by Weyerhaeuser in Louisiana during 2006-2007. Our objectives were to examine effects of row spacing and debris distribution on vegetation, to look at responses of small mammal densities to row spacing and debris distribution, and to see how small mammals …


Using Combined Prediction Models To Quantify And Visualize Stormwater Runoff In An Urban Watershed, Keshia Koehn, Cristina Scarlat, Kristofor Brye Jan 2008

Using Combined Prediction Models To Quantify And Visualize Stormwater Runoff In An Urban Watershed, Keshia Koehn, Cristina Scarlat, Kristofor Brye

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Stormwater runoff can transport nutrients, sediments, chemicals, and pathogens to surface waterbodies. Managing runoff is crucial to preserving water quality in rapidly developing urban watersheds like those in Northwest Arkansas. A watershed containing the majority of the University of Arkansas campus was designated as the study area because stormwater from it drains into the West Fork of the White River, designated as an impaired waterbody due to siltation. The project objective was to develop methodology to test existing stormwater drainage infrastructure, identify potential areas of improvement, and estimate potentially contaminated runoff by combining two widely used prediction models. The U.S. …


Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2006, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman Jan 2008

Current Status And Long-Term Trends In Water Quality And Living Resources In The Virginia Tributaries And Chesapeake Bay Mainstem From 1985 Through 2006, Daniel M. Dauer, Harold G. Marshall, John R. Donat, Michael F. Lane, Suzanne C. Doughten, Frederick A. Hoffman

Status and Trends for Virginia Chesapeake Bay

The period prior to the implementation of the Chesapeake Bay Monitoring Program was characterized by a marked decline in the water quality of the Chesapeake Bay. The disappearance of submerged aquatic vegetation in certain regions of the Bay, declines in the abundance of some commercially and recreationally important species, increases in the incidence of low dissolved oxygen events, changes in the Bay's food web, and other ecological problems have been related to the deteriorating water quality (e.g. USEPA, 1982,1983;Officer et al.,1984; Orth and Moore, 1984). The results of concentrated research efforts in the late 1970s and early 1980s stimulated the …


The Impacts Of River Impoundment: A Case Study Of H. Neely Henry Lake In Northeast Alabama, Willis Scott Estis Jan 2008

The Impacts Of River Impoundment: A Case Study Of H. Neely Henry Lake In Northeast Alabama, Willis Scott Estis

LSU Master's Theses

Dam building is one of the methods that modern civilization uses in an attempt to harness the power of nature. These dams and the impoundments associated with them can contribute numerous positive impacts to the surrounding human population. Unfortunately, there are negative impacts as well. This research focuses on one impoundment in particular, H. Neely Henry Lake in northeast Alabama (an impoundment of the Coosa River). Site-specific information regarding the H. Neely Henry development is explored including area geography, history, and the formation of the Alabama Power Company – the agency responsible for H. Neely Henry and other Coosa River …


An Analysis Of The Benefits And Patterns Of Public Support For Urban Forestry Programs, Barbi Marisa Landano Jan 2008

An Analysis Of The Benefits And Patterns Of Public Support For Urban Forestry Programs, Barbi Marisa Landano

LSU Master's Theses

Trees are an essential element in a healthy urban community. They provide many benefits if they are properly managed and maintained throughout their lives. In order to accomplish this, urban forestry programs need to be established and there needs to be a good support system within the city. The objectives of this study are to identify key factors that may influence public support for urban forestry programs and to examine the role of nonprofit organizations in building support for and implementing urban forest programs. Surveys of Baton Rouge, Louisiana residents were conducted to identify the variables that are associated with …


The Balancing Act, David Weaver Jan 2008

The Balancing Act, David Weaver

Conference papers and presentations

Nutrient management is as much a global issue as a local one with a balance required between economics and environment, inherent biological limitations and expectations of nutrient use efficiency, and traditional fertiliser practices and actual enterprise nutrient requirements. The concept of nutrient balance depends on context and scale. Nutrient balance can be considered at a global scale, where issues of nutrient stocks, cycles, depletion and transfer of a particular element are important. For a single farm enterprise, nutrient balance might be considered in terms of phosphorus (P) inputs into and outputs from the enterprise. This is commonly known as a …


Identification Of Quantitative Trait Loci Influencing Early Height Growth In Longleaf Pine (Pinus Palustris Mill), Lisha Wu Jan 2008

Identification Of Quantitative Trait Loci Influencing Early Height Growth In Longleaf Pine (Pinus Palustris Mill), Lisha Wu

LSU Doctoral Dissertations

The delay in early height growth (EHG) has been a limiting factor for artificial regeneration of longleaf pine (Pinus palustris Mill.). Simple Sequence Repeat (SSR) markers have been used to map the genome and quantitative trait loci controlling the EHG in a backcross family (longleaf pine x slash pine) x longleaf pine. A total of 228 locus specific SSR markers were screened against 6 longleaf pine recurrent parents and a sample of 7 longlef x slash pine hybrid parents. In total, 135 polymorphic markers were identified. Based on the genetic variance in EHG, available sample size, and the number of …


Spatial And Temporal Dynamics Of Stream Water Chemistry In A Headwater Catchment Of Central Louisiana, April Bryantmason Jan 2008

Spatial And Temporal Dynamics Of Stream Water Chemistry In A Headwater Catchment Of Central Louisiana, April Bryantmason

LSU Master's Theses

One of the dominant themes of stream water quality research has been the effect of nutrients and organic materials on eutrophication of coastal waters. Despite this prevalence in water quality research, few studies have been conducted on water quality changes in low-gradient watersheds under a humid, warm subtropical climate, such as those in the coastal plains of the Northern Gulf of Mexico. This study addresses: (1) the nutrient conditions in headwater streams of a low-gradient, subtropical watershed, especially as it relates to the suggested criteria by the Environtmental Protection Agency (EPA), (2) organic and inorganic carbon dynamics in the headwaters …


Photonic-Based Spectral Reflectance Sensor For Ground-Based Plant Detection And Weed Discrimination, Arie Paap, Sreten Askraba, Kamal Alameh, John Rowe Jan 2008

Photonic-Based Spectral Reflectance Sensor For Ground-Based Plant Detection And Weed Discrimination, Arie Paap, Sreten Askraba, Kamal Alameh, John Rowe

Research outputs pre 2011

A bench prototype photonic-based spectral reflectance sensor architecture for use in selective herbicide spraying systems performing non-contact spectral reflectance measurements of plants and soil is described and experimental data obtained with simulated farming vehicle traveling speeds of 7 and 22 km/h is presented. The sensor uses a three-wavelength laser diode module that sequentially emits identically-polarized laser light beams through a common aperture, along one optical path. Each laser beam enters a multi-spot beam generator which produces up to 14 parallel laser beams over a 210mm span. The intensity of the reflected light from each spot is detected by a high-speed …


Climate Change And Freshwater Resources, Robert H. Abrams, Noah D. Hall, Bret B. Stuntz Jan 2008

Climate Change And Freshwater Resources, Robert H. Abrams, Noah D. Hall, Bret B. Stuntz

Journal Publications

Earth's climate is warming. This is the unequivocal conclusion of climate scientists. Despite the complexities of climatology, certain consistent trends emerge with implications for water availability: as the world gets warmer, it will experience increased regional variability in precipitation, with more frequent heavy precipitation events and more susceptibility to drought. These simple facts will have a profound impact on freshwater resources throughout the United States, as the warmer climate will reduce available water supplies and increase water demand. Unfortunately, current water law and policy are not up to the new challenges of climate change and resulting pressures on freshwater resources. …


State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2008, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University Jan 2008

State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2008, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University

State of the River Report

No abstract provided.


The Identification And Characterization Of Phenylalanine Ammonia-Lyase Gene Family Members In Glycine Max, Erin Kathleen Pringle Jan 2008

The Identification And Characterization Of Phenylalanine Ammonia-Lyase Gene Family Members In Glycine Max, Erin Kathleen Pringle

Masters Theses

"Gene families are collections of genes with similar functions. Studying gene families is important for understanding the evolution of genes and manipulating genes. Phenylalanine ammonia-lyase (PAL) is an enzyme found in plants. It catalyzes the deamination of phenylalanine to produce cinnamic acid. Genes for PAL have been identified in many different plant species. This project used the known sequence for the PAL1 gene in Glycine max to find other PAL genes in Glycine max"--Abstract, page iii.


Dual Regulation, Collaborative Management, Or Layered Federalism: Can Cooperative Federalism Models From Other Laws Save Our Public Lands?, Hope M. Babcock Jan 2008

Dual Regulation, Collaborative Management, Or Layered Federalism: Can Cooperative Federalism Models From Other Laws Save Our Public Lands?, Hope M. Babcock

Georgetown Law Faculty Publications and Other Works

To realize the goals of conservation biology and ecosystem management, the institutions that govern these systems must be able to work together harmoniously, across political boundary lines and into a biologically uncertain future. The rigidity of the current public lands model creates substantial barriers to the achievement of these goals.

This article's working premise is that unless the current governance structure for the management of public lands changes, the political conflicts over their use and management will continue to blight their future, just as it has marred their past. Further, failing to adapt the management of public lands to our …


Estimation Of Evapotranspiration Of Cottonwood Trees In The Cibola National Wildlife Refuge, Cibola, Arizona, Amity J. Jetton Jan 2008

Estimation Of Evapotranspiration Of Cottonwood Trees In The Cibola National Wildlife Refuge, Cibola, Arizona, Amity J. Jetton

Browse all Theses and Dissertations

This study used sap flow measurements and satellite imagery to estimatewater use by cottonwood (Populus fremontii S. Wats. ssp) trees in an irrigated restoration plot at Cibola National Wildlife Refuge on the Lower Colorado River. Several thousand hectares of irrigated plots of this type are planned to improve riparian habitat on the river, hence it is important to know how much water the trees require. In this study, the ET rates for 20 Freemont cottonwood trees, from an 8 ha plot, were monitored over a 30-day period. ET rates were estimated by measuring sap flow through branches of the trees. …


Deer Impact On Vegetation In Natural Areas In Southeastern Nebraska, Joseph Gubanyi, Julie A. Savidge, Scott E. Hygnstrom, Kurt C. Vercauteren, Gary W. Garabrandt, Seth Korte Jan 2008

Deer Impact On Vegetation In Natural Areas In Southeastern Nebraska, Joseph Gubanyi, Julie A. Savidge, Scott E. Hygnstrom, Kurt C. Vercauteren, Gary W. Garabrandt, Seth Korte

United States Department of Agriculture Wildlife Services: Staff Publications

We studied the effect of browsing by white-tailed deer (Odocoileus virginianus Zimmerman) on vegetation at three sites with high densities of deer and six sites with low densities of deer along the Missouri and Platte Rivers in southeastern Nebraska in 1995-1996. Vegetation volume from 0-1 m high was similar between sites with high and low deer densities (P > 0.05). From 1-2 m high, vegetation volume was less at sites with more deer in both years (P < 0.05). Densities for eight of 11 small woody plant categories (< 3 cm dbh) were less common at sites with high densities of deer (P < 0.05). Overall densities of small trees (3-15 cm dbh) were similar between sites with high and low densities of deer. However, small hackberry trees (Celtis occidentalis L.) were more common (P = 0.03), while all other small trees were less common (P = 0.038), at sites with …


Passive Immunity To West Nile Virus Provides Limited Protection In A Common Passerine Species, Nicole M. Nemeth, Paul T. Oesterle, Richard A. Bowen Jan 2008

Passive Immunity To West Nile Virus Provides Limited Protection In A Common Passerine Species, Nicole M. Nemeth, Paul T. Oesterle, Richard A. Bowen

United States Department of Agriculture Wildlife Services: Staff Publications

Passerine birds have played an important role in the establishment, maintenance, and spread of West Nile virus (WNV) in North America, and some are susceptible to WNV-associated mortality. Characterization of passive transfer of anti-WNV antibodies in passerines is important to understanding transmission and demographic effects of WNV on wild birds. We showed passively acquired maternal antibodies to WNV in the house sparrow (Passer domesticus). Although all seropositive females (N = 18) produced antibody-positive egg yolks, only 20% of seropositive mothers (3/15) produced seropositive chicks. The estimated average half-life of maternal antibodies in chick sera was 3 days, …


Skunk Rabies In California (1992–2003)—Implications For Oral Rabies Vaccination, Ray T. Sterner, Ben Sun, Jean B. Bourassa, Robert L. Hale, Stephanie A. Shwiff, Michele T. Jay, Dennis Slate Jan 2008

Skunk Rabies In California (1992–2003)—Implications For Oral Rabies Vaccination, Ray T. Sterner, Ben Sun, Jean B. Bourassa, Robert L. Hale, Stephanie A. Shwiff, Michele T. Jay, Dennis Slate

United States Department of Agriculture Wildlife Services: Staff Publications

Skunk-variant rabies is endemic in California (United States), and the development of oral vaccines and baits to vaccinate skunks is in progress. In 2003, the California Department of Public Health (CDPH) began to quantify the impacts of skunk-variant rabies and to assess the feasibility of using oral rabies vaccination (ORV) as a containment measure. The CDPH rabies case data for skunks were spatially depicted and analyzed using a geographic information system. Statewide, rabid skunks (1992–2003) primarily occurred in seven physiographic regions: Central Coast, North Coast, North Sierra, Sacramento Valley, San Francisco Bay and Delta, San Joaquin Valley, and South Sierra. …


Food Color, Flavor, And Conditioned Avoidance Among Red-Winged Blackbirds, Scott J. Werner, Bruce A. Kimball, Frederick D. Provenza Jan 2008

Food Color, Flavor, And Conditioned Avoidance Among Red-Winged Blackbirds, Scott J. Werner, Bruce A. Kimball, Frederick D. Provenza

United States Department of Agriculture Wildlife Services: Staff Publications

The relationship between food flavors and postingestive feedback enables mammalian herbivores to procure nutrients and avoid toxins within ever-changing environments. We conducted four experiments with red-winged blackbirds (Agelaius phoeniceus) in captivity to determine the relative roles of color and flavor cues paired with negative postingestive feedback. We first conducted baseline tests to assess preferences for colors and flavors. All blackbirds preferred red- to blue-colored food, and they preferred umami- (L-alanine) flavored to bitter/astringent food (tannic acid). We observed no difference in consumption of salty (NaCl) vs sour (citric acid) foods during baseline tests (i.e., neutral flavors). We then …


Sttructure-Function Correlations Of The Antagonist Effects Of Flavonoids Present In Medicinal Plants On Oxidative Reactive Molecules, Deema Khalil Al Jayousi Jan 2008

Sttructure-Function Correlations Of The Antagonist Effects Of Flavonoids Present In Medicinal Plants On Oxidative Reactive Molecules, Deema Khalil Al Jayousi

Theses

Flavonoids are phenolic compounds with significant antioxidant properties. The propensity of a flavonoid to inhibit free-radical mediated events is governed by its chemical structure. Since these compounds are based on the flavan nucleus, the number, positions, and types of substitutions influence radical scavenging and chelating activity. The main objective of this thesis was to establish structure-activity relationships of flavonoids by means of experimental and computational techniques.

Initially, a series of dietary flavonoids belonging to the most representative families (flavonols; myricetin, quercetin, morin, kaempferol, and 3-hydrxoyflavone, flavones; flavone and flavanones; naringenin) were studied during the reaction with DPPH radical following addition …


Dissolution Kinetics Of Sulfate Minerals: Linking Environmental Significance Of Mineral-Water Interface Reactions To The Retention Of Aqueous Cro42- In Natural Waters, Sweta Bose Jan 2008

Dissolution Kinetics Of Sulfate Minerals: Linking Environmental Significance Of Mineral-Water Interface Reactions To The Retention Of Aqueous Cro42- In Natural Waters, Sweta Bose

Browse all Theses and Dissertations

Dissolution as a function of solution undersaturation (Ω) was studied on both celestite and barite (001) by the aid of atomic force microscopy (AFM). Both the sulfates exhibited non-linear reactivity trends showing increasing dissolution rates with decreasing Ω. In the case of celestite, the dissolution rate non linearity was attributed to a changeover in reaction mechanism. At higher undersaturations below a critical saturation state of Ωcrit ~ 0.1, dissolution occurred both along the existing step edges and also via the creation of new steps. At conditions near saturation states dissolution took place exclusively by removal of ions from existing …


An Assessment Of The Allelopathic Potential Of Alliaria Petiolata, Eulondia Kathryn Barto Jan 2008

An Assessment Of The Allelopathic Potential Of Alliaria Petiolata, Eulondia Kathryn Barto

Browse all Theses and Dissertations

Garlic mustard (GM), Alliaria petiolata, a European biennial herb invasive in North America, produces secondary metabolites that may contribute to its invasive success by allelopathically inhibiting growth of native plants. I tested this hypothesis by determining the levels, and stability, of these compounds in field soils. I also explored differences in the phytochemical profiles of GM and closely related North American species, and biogeographic differences in allelopathic effects on North American and European arbuscular mycorrhizal fungi (AMF). Furthermore, I exposed a North American annual herb, pale jewelweed (Impatiens pallida), and its AMF, to GM extracts in order …