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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 …

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 …

Age, Growth, And Reproductive Biology, Of The Winter Skate, Leucoraja Ocellata, In The Western Gulf Of Maine, James Antoni Sulikowski

Doctoral Dissertations

This study describes the age, growth and reproductive biology of the winter skate, Leucoraja ocellata, in the Western Gulf of Maine. Age was estimated by enumerating annular bands within the vertebral centra. Precision of the age estimates was evaluated using the Index of Average Percent Error and the annual nature of growth band formation was documented using marginal increment analyses. Growth was assessed with the use of the von Bertalanffy growth equation. Age and size at maturity was estimated by measuring morphological and histological changes in the reproductive tract and circulating steroid hormone concentrations. Maturity ogives for males predict that …

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 …