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An Ecological Assessment Of Wetland Mitigation Projects In East Tennessee, Kim Pilarski

Masters Theses

Federal wetland protection regulations stipulate that developers who destroy natural wetlands are required to construct mitigation or replacement wetlands. Despite the frequency of wetland mitigation, few studies have evaluated the ability of mitigated wetlands to mimic the ecological function and community composition of natural wetlands. Fewer still compare mitigation sites with existing natural wetlands in the same ecological region.

Studies from other freshwater habitats suggest that comparisons of the ratios of functional feeding groups (FFGs) of benthic macroinvertebrates (i.e., shredders, scrapers, collectors, predators) may provide useful information about the ability of mitigated wetlands to mimic the ecological functions of natural …

Utilization Of Half-Log Structures As Spawning Sites For Smallmouth Bass In Norris Reservoir, Tennessee, Keith A. Patrick

Masters Theses

SCUBA observations were used to evaluate the utilization of half-logs by naturally spawning smallmouth bass (Micropterus dolomieu). Of the 736 half-logs which were installed in Norris Reservoir in 1993, 22% of the total (161) logs were evaluated weekly at three different sites from 2 April 1996 and continuing through 25 June 1996. There were 88 line-transects, each 12.2 m in length, used as controls and positioned in non-structure areas; the transects were located at the same water depths as the half-log structures.

Species found utilizing the half-logs for spawning were smallmouth bass, bluegill (Lepomis macrochirus), black …

The Interactive Effect Of Shade And Drought On Seedling Growth And Survival, Milena Holmgren

Doctoral Dissertations

The hypothesis that plants face a trade-off between shade and drought tolerance is examined. Smith and Huston (1989) had used the trade-off model to predict the growth and survival of different plant functional types along gradients of light and water availability, and showed that several natural patterns of plant distribution and succession could, in principle, be explained from this hypothesized response-model. Based on a set of assumptions on plant morphological and physiological responses to drought and shade, the authors had predicted that under drier conditions plants would become less shade tolerant, and, therefore, would grow and survive better under higher …

The Cliff Ecology And Genetic Structure Of Northern White Cedar (Thuja Occidentalis L.) In Its Southern Disjunct Range, John Mikell Young

Masters Theses

In the southern portion of its disjunct range, northern white cedar (Thuja occidentalis L.) is a glacial relict that typically occurs on north-facing, limestone cliffs along deeply entrenched stream and river valleys. Cliff Thuja populations occur across a mosaic of physiographic provinces that comprise a heterogeneous landscape of variable topographic, lithologic, and climatic conditions. Habitat heterogeneity is observed within cliff sites, where Thuja stems occur on sheer cliff faces and less frequently along thin corridors cliff top and/or cliff bottom habitat. Several associate species, including additional relict ones, are also distributed among these cliff habitats I sampled and described …