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Sampling Of Soils With Metallic Residues Collected From Military Small-Arms Ranges, Jay L. Clausen

Doctoral Dissertations

Small-arms, artillery, mortar, and pyrotechnic military training introduces solid metallic residues into the environment. Previous energetic residue research showed conventional judgmental soil sampling and associated sample preparation methodologies are inadequate to address the heterogeneous distribution and still yield representative and reproducible results for the area of interest. Metallic residue deposition at military small-arms ranges occurs in a heterogeneous distributional pattern, similar to solid particulate energetic residue deposition.

One of the primary objectives of an environmental investigation is to estimate the mean contaminant concentration to evaluate human and ecological risk in an exposure unit (i.e., an area where the receptors are …

Remote Sensing Of Foliar Nitrogen In Cultivated Grasslands Of Human Dominated Landscapes, Paul Adam Pellissier

Master's Theses and Capstones

Foliar nitrogen (N) concentration of plant canopies plays a central role in a number of important ecosystem processes and continues to be an active subject in the field of remote sensing. Previous efforts to estimate foliar N at the landscape scale have primarily focused on intact forests and grasslands using aircraft imaging spectrometry and various techniques of statistical calibration and modeling. The present study was designed to extend this work by examining the potential to estimate the foliar N concentration of residential, agricultural and other cultivated grassland areas within a suburbanizing watershed. In conjunction with ground-based vegetation sampling, we developed …

Characterization And Distribution Of Fungi Associated With Needle Defoliation Of Eastern White Pine (Pinus Strobus), Stephen Andrew Wyka

Master's Theses and Capstones

Over the past seven years eastern white pines (Pinus strobus) across the northeastern United States have been prematurely defoliating due to a disease complex known as White Pine Needle Damage (WPND). Previous research on WPND indicates that this outbreak, which started in 2010, is primarily attributed to the causal agent of brown spot needle blight, Lecanosticta acicola along with two other known P. strobus needle cast pathogens, Bifusella linearis and Lophophacidium dooksii. The current outbreak is thought to have arisen from several consecutive years of increased temperature and precipitation in the region. Current research, however, is lacking in both sampling …

Estimating Surficial Seafloor Sediment Properties Using An Empirical Orthogonal Decomposition On Acoustic Backscatter Waveform Properties, Joshua Lincoln Humberston

Master's Theses and Capstones

Seafloor classification and environmental assessment in shallow marine waters are crucial to habitat mapping, coastal management policies and maintaining navigational waterways. There are existing methods for remotely estimating some bottom properties, but the large variety of desired measured sediment properties frequently leads to insufficient quantifiable data to support marine policy decisions. This problem is exacerbated by the highly variable bottom composition of typical coastal and estuarine environments. In this work, field observations from an Odom Echotrac vertical-incidence echosounder with a 200 khz transducer were used to estimate seafloor sediment characteristics in regions with variable bottom types. Observations were obtained in …