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A Comparison Of Floristic Diversity In Old-Growth Versus Mid-Successional Secondary-Growth Hardwood Forests Of The White Mountain National Forest, New Hampshire, United States, Leslie Marie Teeling-Adams

Doctoral Dissertations

There is currently debate over whether managed forests will ever regain the species diversity of old-growth stands. While succession and response to disturbance of tree species has been extensively researched, little similar effort has focused on understory herbaceous communities. This study conducted large-scale, comprehensive botanical inventories of three old-growth and three mid-successional (80--100 year old) secondary forest stands in New Hampshire's White Mountain National Forest (WMNF). Cluster analysis and TWINSPAN grouped the secondary sites within two steps. Old-growth floras were significantly richer in total, total herbaceous, woodland herbaceous, and unique herbaceous species. Abundance distributions of the two treatment groups were …

Evaluation Of Bacteriophage And Viral Persistence During Alkaline Stabilization In Sludge And Biosolids Intended For Land Application, Jacqueline Joy Brabants

Doctoral Dissertations

The use of lime to reduce or eliminate pathogen content is a cost-effective treatment method currently being employed in many Class B biosolids production plants in the United States. A bench scale model of lime stabilization was designed to evaluate pathogen persistence. The survivability of poliovirus type 1, fecal coliforms, Salmonella, adenovirus type 5, rotavirus Wa, and the male-specific bacteriophage MS-2 was evaluated under lime stabilization conditions in various matrices. Salmonella and fecal coliforms were evaluated at 28°C and poliovirus and MS-2 were evaluated at both 28°C and 4°C for survivability under lime stabilization conditions in a sludge matrix. All …

Spatial Modeling And Visualization Of Habitat Response To Hydrologic Restoration In New England Salt Marshes, Raymond Anthony Konisky

Doctoral Dissertations

Anthropogenic alterations that restrict tidal flows negatively impact 20% of New England salt marshes, but management attempts to restore tides to these sites can be met with unexpected or less than optimal results. Restoration planners may be hindered by a lack of synthesized information regarding important biotic and abiotic factors that determine the distribution of dominant salt marsh plants and invasive species. An ecosystem model was developed to better predict salt marsh habitat response to hydrologic modification as a synthesis of existing models for biomass production, marsh elevation, tidal hydrology, and plant succession. A field experiment was conducted to provide …

Factors Associated With Atlantic White -Cedar Seedling Recruitment On Microtopographic And Landscape Scales, Brown Mill Pond, Rye, New Hampshire, Lara Megdane Gengarelly

Doctoral Dissertations

The decline of Atlantic white-cedar (Chamaecyparis thyoides) throughout its range has motivated researchers to investigate cedar seedling recruitment. In this study, conducted at Brown Mill Pond in Rye, New Hampshire, the distribution pattern of cedar seedlings was studied in order to identify which, if any, biological or physical factors observed at a microtopographic scale were associated with seedling presence. On a landscape scale, five previously identified cedar communities were measured for differences in water table level and soil moisture in order to determine associations between stand dynamics and hydrology.

A field survey showed that cedar seedlings were (1) absent from …

Factors Affecting Plant Community Composition And Dynamics In The Ossipee Pine Barrens, New Hampshire, Lauren Fredrick Howard

Doctoral Dissertations

Forty-one 0.25 ha sites were sampled in the Ossipee Pine Barrens to identify and describe tree community types and investigate factors controlling forest composition and dynamics. Every site had three site-time assemblages (STA's) representing past, present, and future trees. Past (1952) vegetation was calculated based on reverse growth estimates of current stems and stumps. Future (2052) vegetation was predicted by current sapling (<10 cm dbh and ≥1 m tall) relative densities.

Cluster analysis produced three community types from 121 STA's: pitch pine, mixed pine-hardwoods, and red maple. Pitch pine communities comprised 63% of sites in 1952, but declined since. Mixed pine-hardwoods peaked at 58% in 2002, but were …

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 …