Life Sciences Commons^™

Forest Development Over A Twenty-Year Chronosequence Of Reforested Urban Sites, Kenton L. Sena, Zachary J. Hackworth, John M. Lhotka

Lewis Honors College Faculty Publications

Urbanization causes a variety of negative ecological impacts, impairing forests, streams, and other ecosystems. While urban forests are the subject of increasing research attention, planted urban forests are less well-understood than remnant forests; however, these systems may be distinct in terms of ecosystem structure and function. The current study investigates a chronosequence of reforested urban sites in Lexington, KY, USA, with a focus on overstory and understory woody plant community characteristics. Monitoring plots were established in each of the 20 sites; tree height, dbh, and species were surveyed for the overstory, and species and height were surveyed for the understory. …

Development Of Mine Soils In A Chronosequence Of Forestry-Reclaimed Sites In Eastern Kentucky, Kenton L. Sena, Kevin M. Yeager, Christopher D. Barton, John M. Lhotka, William E. Bond, Kimberly J. Schindler

Lewis Honors College Faculty Publications

Surface mining for coal has contributed to widespread deforestation and soil loss in coal mining regions around the world, and particularly in Appalachia, USA. Mined land reforestation is of interest in this and other regions where forests are the dominant pre-mining land use. This study evaluated mine soil development on surface-mined sites reforested according to the Forestry Reclamation Approach, representing a chronosequence of time ranging from 0 to 19 years after reclamation. Soils were sampled in depth increments to 50 cm and analyzed for a suite of soil physical and chemical characteristics. Overall, soil fines (silt + clay) tended to …

The Impacts Of Imazapic On Garlic Mustard And Non-Target Forest Floor Vegetation In Central Kentucky’S Hardwood Forests, Pavan Kumar Podapati

Theses and Dissertations--Forestry and Natural Resources

Alliaria petiolata is an invasive biennial herb that poses a substantial threat to various ecosystems across the United States. Imazapic herbicide can control A. petiolata infestations, but there is limited peer-reviewed data on impacts of pre-emergent imazapic spraying to forest floor communities. This research examined the impacts of pre-emergent imazapic (0.84 kg/ha) with Pentra-Bark® surfactant on ground cover of A. petiolata and the spring perennials Claytonia virginica and Erigenia bulbosa. Experimental populations in randomized blocks within two forest stands in central Kentucky received the following treatments at 0.84 kg ai/ha: imazapic with Pentra-Bark®, glyphosate with Pentra-Bark®, Pentra-Bark® alone, and …

Sustainability And Economics Of White Oak (Quercus Alba) Timber Supply In Kentucky, Gaurav Dhungel

Theses and Dissertations--Forestry and Natural Resources

Sustained timber supply relies upon balanced forest age distribution, where the level of harvesting and mortality is compensated by regeneration and growth among younger age classes. However, current forest inventory trends from the white oak growing region reveal sustainability threat from declining white oak regeneration and recruitment leading to disproportionate inventory structure. Consequently, there exists growing concern among stakeholders on long-term sustainability of white oak timber and its economic implications, particularly in Kentucky, because of the significance of the species to the state’s economy. This research aims to examine past and current inventory levels of white oak in Kentucky using …

Residual Spatial Autocorrelation In Macroecological And Biogeographical Modeling: A Review, Guetchine Gaspard

Theses and Dissertations--Geography

Macroecological and biogeographical modelers have predicted the distribution of species across space relying on the relationship between biotic processes and environmental variables. Such a method employs data associated, for instance, with species abundance or presence/absence, climate, geomorphology, and soils. Statistical analyses found in previous studies have highlighted the importance of accounting for the effects of spatial autocorrelation (SAC), which indicates a level of dependence between pairs of nearby observations. A consensus has existed that residual spatial autocorrelation (rSAC) can substantially impact modeling processes and inferences. However, more emphasis should be put on identifying the sources of rSAC and the degree …

Southern Pine Beetle-Specific Rna Interference Demonstrates No Effects On Nontarget Insects, Hannah Marie Hollowell

Theses and Dissertations--Entomology

The endemic southern pine beetle (SPB), Dendroctonus frontalis Zimmermann, is a highly destructive bark beetle that has devastated coniferous forests of the southern United States for decades. Traditional management strategies have been unable to respond effectively to largescale SPB outbreaks, prompting exploration of novel techniques including RNA interference (RNAi). Double-stranded RNAs (dsRNAs) are effective at triggering gene silencing and inducing mortality in SPB, but determining delivery methods and demonstrating specificity of the treatments is necessary before this technology may progress to deployment.

I evaluated three SPB-specific dsRNAs on model nontarget insects to assess potential lethal effects, sublethal effects such as …