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Bacterial Biodegradation Of Soluble Crude Oil Hydrocarbons And The Influence Of Protists In Simulated Arctic Seawater And Sea Ice, Heather Ballestero
Bacterial Biodegradation Of Soluble Crude Oil Hydrocarbons And The Influence Of Protists In Simulated Arctic Seawater And Sea Ice, Heather Ballestero
Doctoral Dissertations
With expected increases in vessel traffic, drilling, and exploration for petroleum and natural gas, the potential for an Arctic oil spill is heightened, yet knowledge of contaminant fate and behavior is limited in this environment. With challenging conditions in the Arctic and limited equipment caches, response will be extremely difficult. In freezing conditions, oil may become encapsulated in ice. Understanding biodegradation potential in this environment can dictate response options for spills that occur in Arctic marine waters. The influence of protists on bacterial biodegradation of water accommodated fractions (WAF) of petroleum hydrocarbons is unknown, yet important because it could enhance …
Sampling And Classification Of Tree Holes Within A Northeast Temperate Forest System, Colleen M. Didas
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 …
Effects Of Urbanization On The Size And Spatial Distribution Of Wetlands In New Hampshire, Katie Jacques
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 …
Statistical And Cartographic Modeling Of Vernal Pool Locations: Incorporating The Spatial Component Into Ecological Modeling, Tina A. Cormier
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 …
Tropical Forest Structure: Ground Measurements Of Coarse Necromass And Satellite Observations Of Crown Geometry, Michael W. Palace
Tropical Forest Structure: Ground Measurements Of Coarse Necromass And Satellite Observations Of Crown Geometry, Michael W. Palace
Doctoral Dissertations
Forests are structurally diverse, but these structures derive from the same processes of disturbance and growth. Understanding forest structure can help unlock the history, function, and future of a forested ecosystem. Components of forest structure include tree size distributions, foliage distributions and variation in canopy density, and coarse woody debris (coarse necromass). Tropical rainforests are structurally the most complex of all ecosystems. In addition to having high biological diversity, Amazon forests are marked by complex vegetation dynamics and a diverse forest stand structures, which play an important role in the interactions of water and carbon between the biosphere and atmosphere. …
Effects Of Forest Clear Cutting On Spotted Salamander ( Ambystoma Maculatum) Migration, Jessica Susannah Veysey
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 …
Characterization Of Prokaryotic Diversity In A Chlorinated Solvent-Contaminated Bedrock Aquifer Using Denaturing Gradient Gel Electrophoresis, Ribosomal Dna Sequencing, And Real Time Pcr, Walid Naser
Doctoral Dissertations
A culture-independent molecular phylogenetic approach was implemented to investigate spatial and temporal variations in microbial diversity and abundance in a chlorinated solvent-contaminated bedrock aquifer. Core and groundwater samples were collected from several boreholes and included the following samples: (1) groundwater that was associated with the core, (2) open fractures and (3) partially mineralized sealed fractures (PMSF) exposed by striking the core with a surface-sterilized geology hammer. DNA representing the attached and unattached microbial communities was extracted from these samples, and the 16S rRNA gene was amplified with primers specific for Bacteria, Archaea, sulfate reducers, Geobacteraceae family, Dehalorespirers (Dehalococcoides sp. and …