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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 …

Abiotic Retention Of Nitrogen And Dissolved Organic Matter By Forest Mineral Soils, Naoko Watanabe

Master's Theses and Capstones

The effect of NO3- deposition on NH4 +, DON, and DOC retention as well as abiotic NO3 - retention via the hypothesized "ferrous wheel" mechanism was examined in oxic and anoxic tropical and oxic temperate soils using sorption isotherm experiments. Adsorption of NH4+, DON, and DOC by mineral soils was examined in forest floor extracts with DOC levels of 0-50 mg/L. Experimental treatments included no added NO3-, 4mg/L of added NO3-, or 4 mg/L of NO3 - and 2 mg/L of Fe3+. Ferric iron was added since it would likely increase DOC retention in the context of podzolization, and it …

Understanding Changes In Aboveground Biomass And Height With Elevation At Hubbard Brook Experimental Forest, Mariya Schilz

Master's Theses and Capstones

A better understanding of carbon stocks and fluxes is a priority of many national and international agencies, including NASA, NACP, IPCC, and IGBP. (Asrar et al. 2001, IGBP Annual Report, 2003, IPCC Third Assessment Report: Climate Change 2001). Patterns of carbon stocks and fluxes on the land surface are important for studies of the carbon cycle, climate change, and terrestrial ecology. One source of heterogeneity is associated with elevation. In systems around the world, patterns in carbon stocks, fluxes, and the factors that underlie them have well documented relationships with elevation (Korner 1999, Schwarz et al. 2003, Waide et al. …

Effects Of Forest Clear Cutting On Spotted Salamander ( Ambystoma Maculatum) Migration, Jessica Susannah Veysey

Master's Theses and Capstones

Upland buffer zones are a proposed management tool for vernal-pool-breeding amphibians. Substantial validation of buffers, via experimental upland habitat disturbance, is lacking. Specifically, no studies have examined immediate effects of clear cutting on spotted salamander (Ambystoma maculatum ) migration. I used clear cutting to experimentally manipulate upland buffer widths at 11 vernal pools. I then radiotracked 40 adult spotted salamanders at these pools, and modeled their migration with mixed-effects regression. Mean maximum distance from the pool was 106.0 +/- 15.4 m (range = 1.6 to 427.6 m). At clear cut-treatment pools, mean percent of time in the cut was 27.2 …

An Evaluation Of The Effect Of Terrain Normalization On Classification Accuracy Of Landsat Etm+ Imagery, Jesse B. Bishop

Master's Theses and Capstones

More than 60% of land in New Zealand has been converted from native forests to residential areas, agriculture, or forest plantations. Settlers brought many species of plants and animals to New Zealand. Many native species were unable to protect themselves from these new predators, causing numerous extinctions. In light of this rapid decline in biodiversity, the New Zealand government has attempted to mitigate the destruction of endemic flora and fauna through both new environmental policies and intensive land management. Land management techniques include the restoration of developed land and the protection of remaining areas of native forest. Monitoring of restoration …

Patterns And Processes Of Soil Carbon Dynamics In A Northeastern United States Forest, Sarah K. Silverberg

Master's Theses and Capstones

Forest soils represent a substantial component of the terrestrial carbon cycle and are an important research area for a number of carbon cycle science initiatives. Whereas patterns of aboveground productivity have been relatively well measured and are increasingly included in regional-scale model analyses, belowground estimates are still highly uncertain and progress has been hampered by methodological difficulties. The lack of data poses a problem because belowground measurements are needed to create complete carbon budgets for terrestrial ecosystems at local, regional and global scales. Ecosystem carbon balances will help identify how and where carbon is being stored, as well as how …

An Experimental Approach To Understanding The Impact Of Vernal Pool Buffer Size On Wood Frogs (Rana Sylvatica), Nicole Alexis Freidenfelds

Master's Theses and Capstones

Strategies to conserve vernal pool-dependent amphibians emphasize the maintenance of adequate areas (buffers) of terrestrial habitat surrounding the pool. I conducted a large-scale field study that specifically examined the effects of buffer width manipulation on adult and metamorph wood frogs at eleven vernal pools in a managed forest in central Maine. Buffer width treatments were 30 m or 100 m forest buffer surrounded by a 100 m clearcut, or no cut (reference). I encircled pools with drift fences and monitored wood frogs from April--November, 2004 and 2005 using pitfall traps and radio-telemetry. Buffer width had no effect on the number …

Characteristics And Dynamics Of A Moose Population In Northern New Hampshire, Anthony Richard Musante

Master's Theses and Capstones

Abundance indices suggest that the moose (Alces alces) population in northern New Hampshire has stabilized despite favorable habitat and conservative harvest. Natural mortality of unknown cause is presumed a primary reason although little is known about moose reproduction and survival in New Hampshire. This study (2002-2005) was designed to investigate the dynamics that impact this population.

Analysis of harvest reproductive data (1988-2004) indicated that average field-dressed weight of adult cows increased although corpora lutea count declined from ∼1.4- 1.2/cow in the study area and statewide. Yearling ovulation rate (∼42%) and average weight (<211 kg) declined about 25% and 4%, respectively. Parturition of radio-marked cows ranged from 8 May-13 July (median=19 May) with 78% of births from 13-27 May. Calving rate of yearlings and adults (>2 yr) averaged 30 and 85%, respectively, …