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Mycorrhizal Colonization And Nutrient Supply Rate Influence Elemental And Isotopic Tracers Of Calcium Cycling In Plant-Substrate Systems, Claire J. Hoff

Master's Theses and Capstones

Intraplant (root-foliage) fractionation of Ca isotopes and Ca/Sr were determined in Pinus sylvestris seedlings grown at different nutrient supply rates with or without ectomycorrhizal colonization. Foliar 44Ca/40Ca and Ca/Sr are uniformly higher than those of roots in individual seedlings, and these ratios in both foliage and roots differed significantly from those of nutrient sources. The measured offsets indicate that isotopic and trace element ratios can identify relative contributions from distinct calcium pools in terrestrial ecosystems. Furthermore, the results clearly show that fractionation of calcium isotopes and calcium from strontium in plants must be assessed in ecosystem-scale budgets and large watershed …

Tracking Bacterial Pollution In The Cains Brook/Mill Creek Watershed: Implications For Policy And Management, Aaron Kornbluth

Master's Theses and Capstones

Pathogenic fecal bacteria present a management challenge when they contaminate surface waters used by humans. This study examined the extent to which the ongoing Cains Brook/Mill Creek watershed restoration in Seabrook, NH has successfully characterized the problem of bacterial pollution and implemented mitigation practices. Guided by the policy sciences analytical framework, this study employed a policy implementation audit reviewing relevant bacteria source tracking data, interviews and online surveys as a means to triangulate multiple data sources. Results indicate that bacteria arise from multiple sources and impairments still exist, although bacteria levels were not generally high. Management activities have likely reduced …

Patterns Of Population Structure And Productivity In Saltmarsh Sparrows, Jennifer Walsh

Master's Theses and Capstones

The Saltmarsh Sparrow (Ammodramus caudacutus) is one of the few species globally that is exclusively restricted to coastal wetlands. Despite the high vagility characteristic of avian species, the highly patchy distribution of tidal marshes can often lead to fine scale genetic structure in salt marsh obligates. To elucidate patterns of population structure, we investigated the degree of genetic differentiation among nine Saltmarsh Sparrow populations along the northeastern coastline of the United States. Although overall FST values were small (0.008), population substructuring was detected along with a positive correlation between geographic distance and genetic differentiation, suggesting that Ammodramus caudacutus follow an …

Secondary Organic Aerosol Formation Of Relevance To The Marine Boundary Layer, Xuyi Cai

Doctoral Dissertations

The chlorine atom (Cl) is a potential oxidant of volatile organic compounds (VOCs) in the atmosphere and is hypothesized to lead to secondary organic aerosol (SOA) formation in coastal areas. The purpose of this dissertation is to test this hypothesis and quantify the SOA formation potentials of some representative biogenic and anthropogenic hydrocarbons when oxidized by Cl in laboratory chamber experiments. The chosen model compounds for biogenic and anthropogenic hydrocarbons in this study are three monoterpenes (alpha-pinene, beta-pinene, and d-limonene) and two aromatics (m-xylene and toluene), respectively. Results indicate that the oxidation of these monoterpenes and aromatics generates significant amounts …

Sustainable Development Of Maritime Cultural Heritage In The Gulf Of Maine, Stefan Claesson

Doctoral Dissertations

In this study the principles of sustainable development and ecosystem-based management are applied to develop a conservation policy for maritime cultural heritage in the Gulf of Maine. This dissertation first examines the effectiveness of existing laws, policies and preservation programs available for the protection and conservation of maritime historical and archaeological resources in the region, and provides an assessment of the diversity and abundance of these resources. Then the principles of sustainability and ecosystem-based management, including inter- and intra-generational equity, precaution, system interconnectedness, and diversity, are applied to form a theoretical framework upon which policies and cultural resource management techniques …

The Local Land Use Process In New Hampshire: Does It Contribute To Sprawl?, Clayton Robert Mitchell

Doctoral Dissertations

In New Hampshire, local communities confront development related impacts, such as, environmental degradation, loss of open space, economic and social structure-based changes, and community character. Local land use regulation is the principal tool available to the municipality that seeks to manage problems associated with growth. The policy decision process employed to develop these policy responses is a complex process of social and political interactions. These decisions and processes are rooted in the community master plan. The master plan serves as the blueprint for a community's vision and its goals. Unfortunately, our understanding of this process is limited.

The policy sciences …

Biomonitoring Polybrominated Diphenyl Ethers In Lactating Women, Rebecca L. Dunn

Doctoral Dissertations

Breast milk is a valuable biological specimen for biomonitoring lipid-soluble polybrominated diphenyl ethers (PBDEs). The goal of this project was to determine the levels of PBDEs in breast milk of lactating women from the Seacoast region of New Hampshire and to examine potential relationships between PBDE levels in breast milk and stage of lactation, maternal characteristics, living environment and dietary intake. Forty women, ages 22 to 40, provided up to three breast milk samples at the end of their first, second and third month of breastfeeding for evaluation of day-to-day and month-to-month variation in PBDE levels. Participants were asked to …

Sources And Sinks Of Selected Trace Gases In The Tropospheric Boundary Layer Of The Eastern United States, Marguerite L. White

Doctoral Dissertations

This dissertation describes three major research projects with the common goal of characterizing sources and sinks of trace gases of strong relevance to regional air quality and global climate issues. In the first study, volatile organic compound (VOC) measurements collected at a marine and continental site in northern New England were compared and examined for evidence of regional VOC sources. Biogenic VOCs, including isoprene, monoterpenes, and oxygenated VOCs, were significant components of the total reactivity at both locations. However, very different VOC distributions were observed for each site. The impact of local anthropogenic hydrocarbon sources such as liquefied petroleum gas …

Conserving Dolphins And Fishermen: Combining Science And Local Knowledge To Reduce Cetacean Bycatch, Erika A. Zollett

Doctoral Dissertations

Bycatch is the portion of catch that is neither targeted nor retained by fishermen. It threatens the survival of many marine mammal populations globally, and it occurs in nearly every fishing gear type. Despite its widespread occurrence, observations of bycatch are rare, and scientific data on marine mammal bycatch are limited. Difficulties result in developing models that accurately depict the interactions. This study focuses on developing methodology to combine disparate data sources, specifically data from fishery observer programs and interviews of fishermen, to better understand these interactions and to identify effective mitigation measures. As a case study, this research investigates …

Geochemical Weathering Of Granular Byproduct Materials, Robert K. Carter

Master's Theses and Capstones

Granular byproducts of artificial systems, such as municipal solid waste incinerator ash (MSWI) and coal combustion, are limited in re-use applications because of concern for their long-term environmental behavior with particular focus on the release of heavy metals. Understanding the solid phases within these materials and their influence on heavy metal leaching is necessary for development of an approach to potential re-use applications. Application of traditional geomorphologic principles may describe the solid phases of man-made systems and their development over time. This research addresses identification of the solid phases by use of Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy …

An Environmental Characterization Of Unbound Mining Residuals From The Tri-State Mining District, Scott Greenwood

Master's Theses and Capstones

The mining and processing of mineral ores presents significant waste management issues due to the large quantities of waste generated and the environmental characteristics of that waste. Conventional waste management options are considered unsustainable and impractical, therefore consideration of alternative options, such as recycling, require investigation. This research analyzed the environmental characteristics of three mining residual samples from the Tri State Mining District to determine if they could be potentially recycled into an unbound highway application.

Testing found that all three samples could be a potentially acceptable aggregate substitute if implemented correctly. Leaching tests showed that the materials did not …

Extreme Precipitation Trends In New England, Susan Grace Spierre

Master's Theses and Capstones

Decision-makers require current data and analysis on extreme precipitation events and trends to facilitate effective adaptation. Here, multiple definitions of extreme precipitation (accumulations of one-inch, two-inch and four-inches, ten-, five- and one-yr. recurrence intervals, and the 99th percentile of events) are used to examine changes in the frequency and intensity of extreme precipitation events in New England over the past 60-100 years. Correlations of trends in extreme precipitation events with temperature and with indices of atmospheric circulation patterns are also investigated.

Predominately positive trends were found for all extreme precipitation definitions. For example, increases of 1 events/decade in one-inch events …

Climate Change Policy: Why Germany Leads And The United States Lags, Kristin Kesling

Master's Theses and Capstones

Why is climate change a top priority on the political agenda in Germany and not a top priority on the political agenda in the United States? This study seeks to answer this question by examining the evolution of climate change policy in both countries. Analyzing Germany's and America's environmental movement, the thesis points to several theories which include the European Union and cultural values. However, it is the nations' political structures/institutions and their post WWII foreign policy views that most determine where climate change policy stands on each country's political agenda. The analysis concludes with a possible outlook on America's …

A Statistical Approach To Understanding Microcosm Methods For Microbially Mediated Dechlorination Of Trichloroethene In Bedrock Aquifers, Stephen J. Druschel

Doctoral Dissertations

Microcosms were evaluated using statistical methods to advance the measurement and characterization abilities for in situ reductive dechlorination of trichloroethene (TCE) in fractured rock aquifers. Microcosms constructed with unincubated crushed rock in groundwater provided the best microcosm model of in situ TCE degradation, when prepared and incubated to simulate the in situ environment. Microcosms constructed with only groundwater were effective at modeling the TCE degradation only when the microcosms were amended with (total) organic carbon (TOC). Incubation of crushed rock core within the residual TCE plume caused a substantial decline in TCE degradation for biotic intrinsic microcosms, suggesting an effect …

Sustainability Of New Hampshire's Sawmill Industry And Its Forest Resource Base, Difei Zhang

Doctoral Dissertations

Sustaining our forests is vital for a healthy ecosystem and for the future of forest industry. To sustain the regional sawmill industry as well as the associated forest resource base, the key is to track the consumption and inventory of eastern white pine (Pinus strobus L.), the most dominant commercial species in New Hampshire. This research profiled the sawmill industry in New Hampshire and Vermont in terms of production, consumption, labor characteristics and regulating economic and policy issues. We examined the sustainability of the industry and its resource base; with a specific focus on the white pine sawmill industry and …

Impacts Of Palustrine Wetlands On Surface Water Quality In The Lamprey River Watershed, New Hampshire, Shelby A. Flint

Master's Theses and Capstones

Surface water chemistry was measured monthly at ten wetlands in New Hampshire from January, 2005 through October, 2006. An additional wetland was sampled intensively and only during summer-autumn, 2005, and summer, 2006. Nitrate, ammonium, dissolved organic nitrogen, total dissolved nitrogen, nitrous oxide, and dissolved organic carbon concentrations in surface waters immediately up- and downstream of the wetlands were compared and changes in concentration were modeled. Nitrate, total nitrogen, organic nitrogen, and organic carbon concentrations differed significantly between upstream and downstream sampling stations. Ammonium and nitrous oxide did not show strong differences between upstream and downstream during much of the sampling …

Microbial Functional Capacity Among Natural And Created Wetlands In Ohio, Usa, Eric J. Saas

Master's Theses and Capstones

Natural depressional wetlands carry out important functions related to C and N cycling, yet the ability of created wetlands to functionally replace natural wetlands in this capacity is not well understood. My objective was to apply the catabolic response profile (CRP) method to evaluate the functional capacity of the soil microbial community in a series of 15 freshwater depressional wetlands: five naturally-occurring wetlands and 10 created wetlands from 1 to 39 years old. I amended sediment samples with 20 labile carbon sources, and samples were analyzed for CO2 and CH4 efflux following a 4-hr incubation under either aerobic or anaerobic …

Nitrogen Loading In Coastal Watersheds Of New Hampshire: An Application Of The Sparrow Model, Kathleen A. Legere

Master's Theses and Capstones

In coastal New Hampshire as well as throughout the world there has been an increase in Nitrogen (N) loading to coastal areas. N is considered the limiting nutrient in coastal waters and can lead to eutrophication. Understanding the sources of coastal inputs is difficult because of the many possible sources of N are found in the watershed and few are adequately sampled. Modeling is an important tool in understanding the sources of N in a watershed. In this research, the New England SPARROW (Spatially Referenced Regression on Watershed Attributes) will be applied to predict nitrogen loading in the Exeter, Oyster, …

Development Of A Numerical Model To Predict Impact Forces On A North Atlantic Right Whale During Collision With A Vessel, Jason J. Raymond

Master's Theses and Capstones

The North Atlantic right whale is under a great deal of public and private concern due to their endangered status and shrinking numbers. Of the 40 animals examined post-mortem (1970-2006), 21 deaths (52.5%) were caused by vessel-whale collision injuries, such as skull fractures. Several methods have been proposed to help reduce the number of fatalities. One such method is to place restrictions on ship speed within right whale critical habitats. However, no quantitative data exist regarding the effect of reduced vessel speed on the likelihood of fatality. The objective of this study is to develop a numerical model of the …

Characterization Of Public And Stakeholder Objectives In Environmental Management: The Application Of Conjoint Analysis And Other Survey Tools To The Management Of The Lamprey River, Shannon Rogers

Master's Theses and Capstones

Management plans for natural resources can be seen as multi-attribute goods that are held in the public domain and therefore require input from experts, stakeholders, and citizens. The state is coordinating an Instream flow study for the Lamprey River in the Seacoast of NH and this research adds a key component to the existing study. This thesis explains how the values and objectives of stakeholders and the general public were elicited. Fourteen stakeholders participated in an interview and survey process and 229 randomly selected residents of the Lamprey River Watershed completed surveys about they how use and value the river. …

Methyl Halide Production In Fungi, Gail D. Dailey

Master's Theses and Capstones

Methyl halide gases are a source of halogen radicals that can react with and destroy stratospheric ozone. The sources of methyl halide gases are both anthropogenic and biogenic, that is, they are human induced and they occur naturally. This research focused on the emission of methyl betides from fungi in the phylum Basidiomycota, which are one of the known biogenic sources.

Previous studies have measured methyl halide production and consumption in soils using field chambers. The objective of this study was to compare production from individual fungi in laboratory cultures to the field measured fluxes to examine whether fungi are …

Red Clover As A Living Mulch: Implications For Sustainable Agriculture And Environmental Conservation, Bill Errickson

Master's Theses and Capstones

This study evaluated the short-term effects of a red clover living mulch on soil physical, chemical and biological properties, in an organically managed tomato agroecosystern in New Hampshire. Four treatments were established, including bare ground with no black plastic (BGNP), bare ground with black plastic (BGBP), red clover with no plastic (LMNP), and red clover with black plastic (LMBP). The effects of these practices are discussed in relation to total soil C and N, N mineralization, microbial biomass, mycorrhizal root colonization, aggregation, bulk density, moisture, and pH. Tomato yield, plant N uptake, and weed emergence were also determined. Large macroaggregates …

Consequences Of Fine-Scale Heterogeneity On Predictions Of The Carbon Cycle Using Lidar Data And A Height-Structured Ecosystem Model, R Quinn Thomas

Master's Theses and Capstones

To more accurately predict carbon stocks and fluxes in forests, it is important to measure fine-scale heterogeneity in ecosystem structure across the landscape, and incorporate the underlying mechanisms responsible for the observed heterogeneity in ecosystem models. This study used large-footprint lidar and a height-structured ecosystem model to estimate carbon stocks and fluxes at Hubbard Brook Experimental Forest (HBEF). At HBEF elevation gradients yield a decline in aboveground carbon stock, due to changes in net growth rates and disturbance at higher elevations. Lidar and a height structured ecosystem model can accurately quantified aboveground carbon stocks. Estimates of aboveground carbon fluxes depended …

Trends In Wintertime Climate Variability In The Northeastern United States, Elizabeth Ann Burakowski

Master's Theses and Capstones

Humans experience climate variability and climate change primarily through changes in weather at local and regional scales. In this work, changes in northeastern United States winter climate are documented using meteorological observations from 1965-2005. Spatial coherence analysis is utilized to remove stations with non-climatic influences from the analysis. Trends over the past four decades in snowfall, snow-covered days, mean, minimum, and maximum temperature are estimated using linear regression.

Northeastern United States regional winter maximum temperatures (+0.43 +/-.08°C/decade) are warming greater rate than minimum (+0.37 +/-0.10°C/decade) and mean (+0.39 +/-0.10°C/decade). Regional winter snowfall decreased by -2.5 +/-0.8 inches/decade. Overall snowfall decreases …

Statistical And Cartographic Modeling Of Vernal Pool Locations: Incorporating The Spatial Component Into Ecological Modeling, Tina A. Cormier

Master's Theses and Capstones

Vernal pools are small, isolated, depressions that experience cyclical periods of inundation and drying. Many species have evolved strategies to utilize the unique characteristics of vernal pools; however, their small size, seasonal nature, and isolation from other, larger water bodies, suggest increased risk of damage/loss by development. The goals of this research were to statistically determine physical predictors of vernal pool presence and, subsequently, to represent the output cartographically for use as a conservation tool. Logistic regression and Classification and Regression Tree (CART) routines were used to define important variables (slope, aspect, land use, soils, and reflectance) of 405 known …

Good Press, Bad Press: A 25-Year Comparison Of Arguments And Trends In American News Coverage Of Climate Change And The Ozone Hole, David Howland

Doctoral Dissertations

This study uses an original content analysis categorical system to seek out and compare the substance of arguments in a quarter century of American news coverage about the ozone hole and climate change. Findings from an examination of more than 1,000 news articles written by The Associated Press, United Press International and The New York Times are combined with interviews with members of key stakeholder groups in both cases including scientists, politicians, industry officials, environmentalists and news reporters. The analysis illuminates the social and political processes at work---that is, those captured by the press---in the evolution of the Montreal ozone …

Assessing The Accuracy Of The Modis Lai 1-Km Product In Southeastern United States Loblolly Pine Plantations: Accounting For Measurement Variance From Ground To Satellite, John Shepherd Iiames Jr.

Doctoral Dissertations

Leaf area index (LAI), defined here as one-half of the total leaf area per unit ground surface area (Chen, 1996), has been estimated at a global scale from spectral data processed from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor aboard two NASA EOS-AM spacecraft, Terra (launched in 1999) and Aqua (launched in 2002). The MOD15A2 LAI product is a 1 km global data product composited over an 8-day period and is derived from a three-dimensional radiative transfer model driven by an atmosphere corrected surface reflectance product (MOD09), a land cover product (MOD12) and ancillary information on surface characteristics. The United …

Gonadal Histology And Reproductive Steroidogenesis Of Anurans Exposed To Potential Endocrine Disrupting Contaminants, Emily May La Fiandra

Doctoral Dissertations

The prevalence of malformed amphibians and the association of high incidences of malformation with the presence of environmental contaminants have raised questions about the effects of environmental contaminants on the development of larval amphibians. The potential endocrine disrupting effects of pesticides suggest that the reproductive and developmental abnormalities observed in larval anurans may be due at least in part to impacts on the hypothalamic-pituitary-gonadal axis. The present studies investigate the effects of exposure to environmental contaminants including DDT and atrazine on the development, gonadal histology and reproductive steroidogenesis of larval anurans.

As previous monitoring at Great Bay National Wildlife Refuge …

Recent Extreme Events In A Tropical Stalagmite: Multi-Proxy Records And Analysis Of Ecosystem Delta Carbon-13 Value Sensitivity To Weak Climate Forcing, Amy E Benoit Frappier

Doctoral Dissertations

Speleothems are emerging as important and detailed chronological records of environmental change. Integrating exploration of modern speleothem records of environmental variability, related forcing factors, and understanding and suggests new potential proxies. This dissertation demonstrates the potential for developing novel proxy records of past regional environmental extremes, such as tropical cyclones, explosive volcanism, and enhanced seasonal contrasts from speleothems that are sensitive to transient infiltration events through very high-resolution, multi-parameter analysis of a rapidly growing, fracture-fed tropical stalagmite. A series of sample screening steps were developed prior to stalagmite collection in the field in order to increase the likelihood of collecting …

Atmospheric Volatile Organic Compound Measurements: Distributions And Effects On Air Quality In Coastal Marine, Rural And Remote Continental Environments, Yong Zhou

Doctoral Dissertations

A detailed description of the analytical methods employed for whole air sampling and analysis of atmospheric volatile organic compounds is presented. The system described in this thesis produced high precision measurements for a large suite of nonmethane hydrocarbons, halocarbons, and alkyl nitrates, from part per billion by volume (ppbv) to part per trillion by volume (pptv) levels. The measurement precision for most gases ranged from 1-10%.

Results from two subsequent field campaigns (2002 and 2003) conducted in Yellowstone National Park (YNP) are presented. The findings indicate that 2-stroke snowmobile engine emissions furnish large quantities of air toxics to the YNP …