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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 …

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 …

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 …

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 …

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 …

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 …

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. …

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 …

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 …

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, …

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 …