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Response Of Tree Growth And Water Use Efficiency To Climate And Nitrogen Deposition In A Temperate Deciduous Forest In The Northeastern Us, Katie Jennings

Master's Theses and Capstones

Nitrogen (N) deposition and climate change are altering tree growth and may have important consequences for water use in northeastern forests. Intrinsic water use efficiency (iWUE), the trade-off between water loss and carbon fixed during photosynthesis, directly links forest carbon and water cycles. Dendrochronology and stable isotopes (delta13C and delta18O) were used to assess Quercus velutina growth and iWUE within a chronic N deposition experiment (20+ years of fertilization at low- and high-N rates). Fertilized trees exhibited sustained growth enhancement, with the greatest response observed for high-N trees. All fertilized trees improved their iWUE through increased photosynthetic rates, but was …

Valuation Of Ecosystem Services: The Case Of Orseg National Park, Hungary, Ildiko Losonci

Master's Theses and Capstones

A chronic lack of sufficient financial resources has prevented many protected area professionals from achieving adequate ecosystem protection. Using a case study of O&huml;rseg National Park in Hungary and the contingent valuation technique, we examined the relative importance of various ecosystem services to respondents, their WTP for these services, and the oath of honesty's effect on hypothetical bias.

Results from the intercept survey that was administered in the park in the summer of 2011 and filled out by 212 respondents show that visitors prefer the protection of the park's cultural monuments, and ecosystems services like local natural food, climate regulation …

Preparing For Climate Change In Three New England Coastal Communities: Lessons On Motivations, Approaches, And Outcomes, Chris Keeley

Master's Theses and Capstones

This case study research investigated three coastal communities in New England engaged in climate change adaptation. The research goals were to (1) Identify and describe the factors that prompt communities to plan for climate change impacts, (2) To elucidate the types of approaches taken by communities in planning for climate change impacts, and (3) To identify outcomes that transpire from engaging in climate adaptation. The major factors prompting climate adaptation included experience with extreme weather events, local leadership on climate change, and access to technical assistance. Each adaptation process was largely stakeholder-driven. The approaches varied and included utilizing local stories …

Effects Of Nitrogen Fertilization On Fungal Community Structure In A Temperate Hardwood Forest: Implicit Links Between Structure, Function And Resilience, Eric W. Morrison

Master's Theses and Capstones

This study documents soil fungal communities at the Harvard Forest Chronic Nitrogen Addition experiment, which was established in 1989 to test the effects of long-term nitrogen fertilization on ecosystem processes. Researchers at this site have observed an accumulation of soil carbon in the nitrogen fertilized plots and a decrease in fungal biomass, ligninolytic enzyme activity, and rates of litter decay. We hypothesized that decreased decomposition rates in nitrogen-fertilized plots were due to changes in the structure of the fungal community, especially Basidiomycetes, the primary decomposers of lignin in this ecosystem. We performed a marker gene study of fungal communities in …

A Comparative Study Of Reactive Caps For Polycyclic Aromatic Hydrocardons In Sediment, John D. Anderson

Master's Theses and Capstones

Some of the most common byproducts from industrial production and hydrocarbon combustion are polycyclic aromatic hydrocarbons (PAHs). These compounds readily adsorb to lake and river sediment, and represent a significant problem to humans and the environment. Capping technologies work as physical barriers between the contamination in the sediment and the greater ecosystem. In this study, capping performance is analyzed based on the removal efficiency of two different organoclay-based treatments and a sand treatment, and the loading rate of PAHs onto the treatment materials. PAH loading rate and removal efficiency indicate the material's ability to sequester PAHs from the aqueous phase …

The Effects Of Historic Earthen Barriers On Northern New England Tital Marshes, Jordan W. Mora

Master's Theses and Capstones

Berms, defined as historic earthen barriers, represent one type of hydrological modification introduced by humans in the tidal marshes of northern New England. Three different research approaches were applied to study the impact of berms on various tidal marsh dynamics. The descriptive study shows that restricted flooding from berm interference can result in significantly altered physical gradients in addition to landward subsidence and pool development. The results from the transplant experiment indicate that the altered landward structure affects the relative importance of biological interactions, namely herbivory, in controlling plant species distribution. The predictive GIS analyses illustrate the location of 34 …

Building And Deployment Of An Automated, In Situ Greenhouse Gas Gas Chromatographic System, Andrew H. Hart

Master's Theses and Capstones

High-precision, continuous monitoring of greenhouse gases, such as carbon dioxide (CO2), methane (CH4), nitrous oxide (N 2O), sulfur hexafluoride (SF6), and the criteria pollutant carbon monoxide (CO), is important for characterizing their regional sources and sinks and understanding how their ambient levels are changing with time and associated anthropogenic activities. For monitoring this suite of gases, a fully automated gas chromatographic based analytical system was built and deployed in the field at the UNH AIRMAP Observing Station at Thompson Farm in Durham, NH. The instrument consists of a Shimadzu 17A gas chromatograph (GC), equipped with a Flame Ionization Detector and …

The Effect Of In Vivo Pbde Treatment On Hepatic Phosphoenolpyruvate Carboxykinase (Pepck) Enzyme Kinetics In Male Wistar Rats, Jessica T. Nash

Master's Theses and Capstones

Polybrominated diphenyl ethers (PBDEs) are synthetic flame-retardant chemicals that enter the environment and mammalian body and may disrupt glucose metabolism. This study investigated the effect of PBDEs on a key gluconeogenic enzyme, phosphoenolpyruvate carboxykinase (PEPCK). Forty-eight male Wistar rats were gavaged with corn oil or corn oil containing 14 mg/kg DE-71 for 3, 14 or 28 days (N = 8 per group). At each time point, fasting plasma glucose, insulin and C-peptide were measured and liver PEPCK enzyme activity was assayed. PBDEs significantly decreased PEPCK Vmax (mumol/min/g liver weight) at 3 days by 26%; this reduction persisted through 28 days. …

Optimized Identification Of Fecal Pollution Sources In A Rural Tidal Watershed In Coastal New Hampshire, Sana B. Hussain

Master's Theses and Capstones

Escherichia coli ribotyping was used to identify fecal contamination sources in Grommet Creek- a tidal creek that drains into Great Bay and contaminates shellfishing beds. Water samples were collected during late summer through late fall. Fecal samples were collected to establish a local source species database. Fecal indicator bacteria were enumerated from water samples and ribotyping was conducted by using EcoR1 restriction enzyme digestion and an automated RiboPrinter(c). There was consistent relative abundance between source types with wild animals and birds as the primary sources. An optimized approach for maximizing source identification involved using a 90% similarity threshold and prioritizing …

A Feasibility Study: Forest Carbon Stocks And Stock Change Of The White Mountain National Forest, Erica Jane Cate

Master's Theses and Capstones

Interest has heightened for forest managers to account for the impacts of management activities on forest carbon sequestration. This study was designed to assess the feasibility of developing estimates of WMNF forest carbon based on the available information. The yield curves, inventory data and resulting carbon projections were dependent on a number of assumptions and subject to various sources of error and bias. Thus, they should not be relied on as definitive estimates and forecasts, or used as a basis for policy recommendations. Under the specific approaches used in this study, forest carbon stocks appear to be accumulating in the …

Age And Age Structure Of An Invasive Plant, Lythrum Salicaria, Kimberly L. Therrien

Master's Theses and Capstones

My objective was to determine whether purple loosestrife (Lythrum salicaria L.) individuals could be aged using the pattern of ramet production. Assuming current year loosestrife ramets produce new basal ramets only in the following year, plant age could be estimated by counting ranks of sequentially produced ramets. I found that in four New Hampshire wetlands the assumptions of the method were generally met, although some ramets were not produced sequentially. Using ramet counts I was able to estimate minimum age for individuals in each of the four populations. All populations were dominated by individuals > 1 year old. I tested whether …

Impacts Of Suburbanization On Food Web Stoichiometry Of Detritus-Based Streams, Nathaniel Burr Morse

Master's Theses and Capstones

Higher non-point source nutrient inputs are one of many impacts associated with the "urban stream syndrome". Research on how non-point source pollution affects the stoichiometry of urban stream food webs has received little attention, however. This study quantified food web stoichiometry in nine headwater, detritus-based streams draining forested or suburban watersheds in northeastern, coastal Massachusetts.

While this study suggests that suburbanization can affect in-stream nutrient recycling by consumers, research that quantifies changes to biomass of different in-stream compartments is needed to calculate the extent of such impacts on suburban stream ecosystems.

Variation In Foliar Nitrogen And Albedo In Response To Nitrogen Fertilization And Elevated Carbon Dioxide, Haley F. Wicklein

Master's Theses and Capstones

It has recently been demonstrated that foliar nitrogen is positively correlated with surface albedo over a broad range of plant functional types. However, the mechanism(s) driving the nitrogen-albedo relationship remain elusive. This study investigated leaf spectral properties from three deciduous species subjected to either nitrogen or CO2 fertilization and compared results to measured chemical and structural properties. We measured reflectance and transmittance, foliar nitrogen, leaf mass per unit area, water content, and d13C values for stacks of 1, 2, 4, and 8 leaves. Nitrogen was the best predictor of leaf-level albedo of the traits that we measured. There were no …

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 …

Sampling And Classification Of Tree Holes Within A Northeast Temperate Forest System, Colleen M. Didas

Master's Theses and Capstones

Tree holes are water filled depressions on trees and harbor macroinvertebrate communities; they often serve as microcosms in studies of population dynamics, competition, and fungal decay of leaf litter. Quantification of tree hole prevalence and incidence in forest stands is lacking in the current literature. This study examined factors influencing tree hole occurrence and the types and formations of tree holes in northeastern forest stands. Modeling was used to correct for non-detection and estimate the abundance of tree holes on a per-hectare basis. Mixed-effects logistic regression was used to predict tree hole occurrence. Tree species, stand basal area, and diameter …

Using Icesat's Geoscience Laser Altimeter System To Assess Large Scale Forest Disturbance Caused By Hurricane Katrina, Katelyn A. Dolan

Master's Theses and Capstones

We assessed the use of GLAS data as a tool to quantify large-scale forest damage. GLAS data for the year prior to and following Hurricane Katrina were compared to wind speed, forest cover, and MODIS NPV maps to analyze senor sampling, and changes in mean canopy height. We detected significant losses in mean canopy height post-Katrina that increased with wind intensity, from ∼.5m in forests hit by tropical storm winds to ∼4m in forests experiencing category two force winds. Season of data acquisition was shown to influence calculations of mean canopy height. There was insufficient sampling to adequately detect changes …

Effects Of Urbanization On The Size And Spatial Distribution Of Wetlands In New Hampshire, Katie Jacques

Master's Theses and Capstones

This study investigates the effects of land use change in the form of urbanization on the size and spatial distribution of wetlands in New Hampshire. I predict that with increased urbanization, the number of wetlands lost will rise, causing an increase in landscape fragmentation. Aerial photography, US Geological Survey topographic maps, National Agriculture Imagery Program imagery, hydrography and National Wetlands Inventory data layers were analyzed using GIS tools along four urban-rural gradient transects 5km by 25km in size. Each study area transect included urban, suburban and rural areas. This study identified the relationships between the urbanization level and the size …

Observations Of Nucleation-Mode Particle Events And Characterization Of Organic Atmospheric Particulate Matter At A Rural New England Site, Philip Fulton Place Jr.

Master's Theses and Capstones

Air quality of New England reflects air quality of the eastern United States and Canada because of transport from these areas to New England. Particle number (PN) concentration, size distribution, and composition were observed in the winter/spring period at a rural New England site (Thompson Farm). Thirteen PN events identified on the basis of increased PN above the site average were investigated, with the majority of events originating from clean northwestern air masses. Steady particle growth rates were observed for events ranging between 0.9 and 5.5 nm.

The organic composition of bulk aerosols were also investigated over a year (August …

An Assessment Of Stress In Acer Saccharum As A Possible Response To Climate Change, Martha Carlson

Master's Theses and Capstones

Climate change is projected to extirpate Acer saccharum throughout its range in the United States. The current investigation evaluates the potential of spectral indices of foliar reflectance, measures of leaf area and bud quality, and historic trends in sap sugar and wood increments for detecting stress in sugar maple.

Thirty trees were examined in 10 plots on 5 sugar bushes in or near the Bearcamp Valley, New Hampshire, over the course of the 2008 growing season. The study found water stress in 100% of trees; reduced chlorophyll content in 60%; early abscission of leaves in 80%; reduced growing season in …

Expanding The Availability Of Sustainable Seafood: Uncovering Barriers For Retailers, Lindsey Piilani Fong

Master's Theses and Capstones

In the fall of 2008, a mail survey was distributed to New England retailers to assess their knowledge and interest regarding 'sustainable seafood' campaigns and eco-labeling programs, as well as identify incentives to help overcome perceived barriers that prevent the distribution of sustainably harvested and labeled seafood in grocery stores. This investigation yields valuable insight for increasing the effectiveness of efforts that aim to influence consumer purchasing of seafood, as there has been little prior investigation of seafood eco-label systems used at the point-of-purchase, or retailer willingness to offer sustainably produced seafood products. This study found that many retailers are …

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 …

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 …

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 …

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 …

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 …

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 …