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A GIS MODEL FOR APIARY SITE SELECTION BASED ON PROXIMITY TO NECTAR SOURCES UTILIZED IN VARIETAL HONEY PRODUCTION ON FORMER MINE SITES IN APPALACHIAPotter, Douglass W. 01 January 2019 (has links)
Beekeepers in Appalachia market varietal honeys derived from particular species of deciduous trees; however, finding places in a mountainous landscape to locate new beeyards is difficult. Site selection is hindered by the high up-front costs of negotiating access to remote areas with limited knowledge of the available forage. Remotely sensed data and species distribution modeling (SDM) of trees important to beekeepers could aid in locating apiary sites at the landscape scale. The objectives of this study are i) using publicly available forest inventory data, to model the spatial distribution of three native tree species that are important to honey producers in eastern Kentucky: American Basswood, Sourwood and Tulip Poplar, and to assess the accuracy of the models, ii) to incorporate a method for discounting the value of a nectar resource as a function of distance based on an energetic model of honeybee foraging, and iii) to provide an example by ranking potential apiary locations around the perimeter of a mine site in the study area based on their proximity to probable species habitat using a GIS model.
Logistic regression models were trained using presence-absence records from 1,059 USFS Forest Inventory and Analysis (FIA) sub-plots distributed throughout a 9,000 km2 portion of the Kentucky River watershed. The models were evaluated by applying them to a separate dataset, 950 forest inventory sub-plots distributed over a 40.5 km2 research forest maintained by the University of Kentucky. Weights derived from an energic model of honeybee foraging were then applied to the probabilities of tree species occurrence predicted by the SDM. As an example, 24 potential apiary locations around the perimeter of a reclaimed mine site were selected and then ranked according to a site suitability index. Three tributary areas corresponding to different honeybee flight ranges were considered: 500m, 700m, and 1,200m. Results confirm that rankings are dependent on the foraging range considered, suggesting that the number of colonies at an apiary location would be an important factor to consider when choosing a site. However, the methodology makes assumptions that are only anecdotally supported, notably i) that colonies will forage preferentially at the target species when it is in bloom and, ii) that foragers will exhaust resources closest to the hive first, regardless of patch size. Additional study of how bees deplete the nectar resources surrounding an apiary is needed to verify the usefulness of SDM in site selection for varietal honey production.
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The Effects of Disturbance and Species Specific Interactions on Diversity in an Agent Based Forest SimulationMills, Matthew E 01 January 2017 (has links)
In ecology literature, there is much data which suggests that conspecific negative density dependence (CNDD) and abiotic disturbances increase biodiversity in forests. This thesis elucidates the notion that not only do these two forces increase diversity, but they may also interact with one another in order to achieve higher levels of biodiversity. Abiotic disturbances, like fires and hurricanes, can indirectly impact conspecific effects because when these forces remove individuals from the landscape, the role of the conspecific effects will change. The interaction of these two factors in biodiversity are explored in an agent based forest simulation through a resource surface. Several different types of abiotic disturbances are simulated with either weak or strong CNDD effects in order to establish that different disturbances and conspecific effects cause certain levels of diversity. The underlying causes for the change in impact is also examined.
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Steps Toward Butternut (Juglans cinerea L.) RestorationBrosi, Sunshine L. 01 August 2010 (has links)
Butternut (Juglans cinerea L.), a lesser-known relative of black walnut (Juglans nigra L.), is a native tree species beneficial for wildlife, valuable for timber, and part of the great diversity of species in the eastern forests of North America. Populations of butternut are being devastated by butternut canker disease, caused by the fungus Sirococcus clavigignenti-juglandacearum (V.M.G. Nair, Kostichka, & Kuntz), which is thought to be introduced to North America. The disease causes multiple branch and stem cankers that eventually girdle trees. Small population sizes, lack of sprouting, and shade intolerance exacerbates the disease and results in permanent losses of butternut across the native range. Fortunately, healthy, canker-free butternut trees have been found proximal to diseased trees, indicating that a breeding approach could be a feasible strategy for producing and reintroducing resistant butternuts. A successful restoration program will require an understanding of genetic variation in open-pollinated seedlings, genetic basis of disease resistance, seedling establishment procedures, site requirements, and a greater understanding of disease development over time.
This dissertation is divided into six parts, with the overall goal of insight into butternut ecology and management techniques which could be used to guide restoration decisions for this important species. The first two parts are an introduction and a literature review. In the third section, butternut seedlings were propagated in nursery progeny plantings to determine the genetic and phenotypic variability among one-year-old seedlings in a controlled environment. Part four outlines the disease development of butternut seedlings across progeny in resistance screening plantings at various locations. Part five aims at aiding restoration techniques by determining the impact of phenotypic and genetic variables on establishment success across various planting sites with different silvicultural treatments. Part six describes the dynamics of a large population of healthy and diseased butternut trees including disease development across temporal scales. The information gained from this research will be directly used in gene conservation strategies, the construction of disease resistant breeding orchards, and in determining appropriate restoration techniques.
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Assessment of Control Charts for Evaluating Dynamic Accuracy of Forest Growth ModelsCristan, Richard Raymond 01 December 2010 (has links)
The purpose of this study was to determine if control charts are an effective tool to identify trends in forest growth and yield model accuracy. Accurate forest growth and yield models are important for projecting future forest composition. However, environmental factors have the potential to make forest growth models created from historic data inaccurate. Control charts in this study determine if forest growth predictions fall within confidence limits established for historic growth at a number of points in time. Two data sets were used in this study: the first was a Continuous Forest Inventory (CFI) from three tracts at the University of Tennessee Cumberland Research Station and the second data set was Forest Inventory and Analysis data collected by the U.S. Forest Service. The CFI plots represented a stand level data set measured every 5 years from 1962-1977 and revisited for a re-measurement in 2009. The FIA plots were a regional data with subsets of plots measured annually from 1999-2008. The FIA data set was limited to plots of the oak/hickory forest type from Tennessee, Alabama, and Georgia. Two forest growth and yield models were used to predict growth: (1) WinYield and (2) Forest Vegetation Simulator (FVS). The two different data sets were used with both FVS and WinYield to evaluate control charts using different models ad at different spatial and temporal scales. The data sets were also subset by site index, stand age, stocking percent, aspect, and species composition to determine if control charts could identify changes in model accuracy for forests subjected to different growing conditions. The CFI and FIA data had short growth predictions and control charts indicated that there were no trends affecting accuracy. The CFI data also had a long growth prediction of 32 years and the control charts found that the predictions using WinYield and FVS were inaccurate, indicating that there may be a trend causing inaccuracy in the model.
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COMPARATIVE ECOPHYSIOLOGY OF AMERICAN CHESTNUT UNDER DIFFERENT PLANTING TREATMENTS ON RECLAIMED MINE SITESMiller, Christopher Ryan 01 May 2010 (has links)
American chestnut was once an abundant species that dominated the Eastern U.S. deciduous forests. Although this species is currently functionally extinct due to the chestnut blight, researchers are working on blight-resistant hybrids in hopes of restoring the species. As one potential vector for chestnut reintroduction and dispersal, the reclamation of mine sites are being considered. Recent research has found that reforestation efforts on these reclaimed mine sites provide productive tree growth while also complying with mine-reclamation laws. Understanding how American chestnut performs physiologically on mine sites will aid in the restoration of this species and reclamation of mine sites.
The objective of this study was to determine the effect planting treatments have on survival, physiology, and performance of American chestnut. The response of American chestnuts under planting treatments varying in planting method, slow-release fertilizer, a hydrophilic root polymer (Terra-Sorb), and the addition of native forest soil were examined at three sites: a mine site, a quarry, and a greenhouse. Results from this study suggest that fertilizer, hydrophilic root polymers and soil microorganisms produce varying effects on dissimilar sites. Greatest overall survival was found in greenhouse-grown bare-root seedlings. The introduction of fertilizer to the soil substrate lowered emergence and survival of directly-seeded trees at the mine site and quarry, but increased tree growth at all sites and photosynthetic rate at the quarry. However, use of fertilizer resulted in a more negative water potential at the mine site and higher transpiration rate, potentially increasing moisture stress and demand. Increased seed survival, growth, and water status can be accomplished through the use of Terra-Sorb, but only in direct seeded trees on sites with potentially deficient plant-available water. Native forest soil can increase survival in both direct seeded and bare-root planted trees. However, more research is needed on the benefits of native forest soil, as growth and physiological results conflict. It is recommended that site characterization be performed prior to selection of planting treatments. Results of this study can prove beneficial to reclamation specialists with an interest in using mine site reclamation in conjunction with American chestnut restoration.
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The Effects of Fire on the Vernal Herbs of an Eastern Mesic ForestKem, David Randolph 01 May 2013 (has links)
The effects of fire on vernal herbs of the mesic forests of eastern North America are poorly understood. I studied the influence of prescribed fire on species richness, abundance of rare and common species, and density of exotics in the vernal herbaceous layer. To determine these effects, three sites in central Kentucky were surveyed prior to and following one of three treatments: spring burn, winter burn, or negative control. I conducted low-intensity spring burns in April 2010 and winter burns in February 2011. I used chi square analyses to test for changes in species richness, abundance of rare species, abundance of common species, and abundance of Glechoma hederacea, an exotic herb. I used multiple logistic regressions to test for the effect of burn severity on the abundance of two of the most common herbs, Erythronium americanum and Viola sororia sensu lato. The abundance of rare species increased significantly after fire treatment, with a 2% greater increase on burned plots than control plots (p < 0.05), and showed a 40% greater increase in plots burned in winter than plots burned in spring. However, there was no significant difference in overall species richness due to fire or to the season in which the prescribed fire was conducted. There were no significant differences in the density of common species or Glechoma hederacea due to fire treatment or due to fire season. There were also no significant differences in the abundances of Erythronium americanum or Viola sororia sensu lato due to burn severity. Changes in the abundance of rare species due to fire might suggest that prescribed burns may slightly increase the diversity of vernal herbs in eastern mesic forests. Changes in the abundance of rare species due to fire season might suggest that prescribed fires conducted prior to emergence may further increase the diversity of vernal herbs in the eastern mesic forest.
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Reestablishing Diversity in Our Hardwood Forests: A Transplant Study of Five Spring-Flowering HerbsRacke, Danielle 01 August 2010 (has links)
Herbaceous communities are critical to the functioning of forest ecosystems. They recycle nutrients, help prevent erosion, provide critical microhabitats and maintain biodiversity. In the eastern United States, most hardwood forests are growing on land once entirely cleared or used for some form of agriculture. Although some of these forests are nearly 150 years old, they still have depauperate native herbaceous communities when compared to remaining old-growth forests. This long-term depletion may result from dispersal limitation or environmental limitation.
I tested the hypothesis that dispersal was the primary factor contributing to the absence of five spring-flowering herbaceous species in four secondary mesic hardwood forests. I transplanted adults and sowed fresh propagules into chosen forests. By establishing negative controls, I showed that propagules of experimental species were not incidentally dispersed and would not have been present at the sites had I not introduced them. In all four sites, seeds of three ant-dispersed species germinated and adults of these species survived, flowered and self-sowed viable propagules. These results strongly indicated dispersal limitation in all sites. Another ant-dispersed species showed evidence of being dispersal-limited in at least two sites. The limitations of one gravity-dispersed species were unclear. I discuss results from the first year after transplanting and offer management suggestions to facilitate the return of these species to degraded forests.
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COMPARATIVE ECOPHYSIOLOGY OF AMERICAN CHESTNUT UNDER DIFFERENT PLANTING TREATMENTS ON RECLAIMED MINE SITESMiller, Christopher Ryan 01 May 2010 (has links)
American chestnut was once an abundant species that dominated the Eastern U.S. deciduous forests. Although this species is currently functionally extinct due to the chestnut blight, researchers are working on blight-resistant hybrids in hopes of restoring the species. As one potential vector for chestnut reintroduction and dispersal, the reclamation of mine sites are being considered. Recent research has found that reforestation efforts on these reclaimed mine sites provide productive tree growth while also complying with mine-reclamation laws. Understanding how American chestnut performs physiologically on mine sites will aid in the restoration of this species and reclamation of mine sites. The objective of this study was to determine the effect planting treatments have on survival, physiology, and performance of American chestnut. The response of American chestnuts under planting treatments varying in planting method, slow-release fertilizer, a hydrophilic root polymer (Terra-Sorb), and the addition of native forest soil were examined at three sites: a mine site, a quarry, and a greenhouse. Results from this study suggest that fertilizer, hydrophilic root polymers and soil microorganisms produce varying effects on dissimilar sites. Greatest overall survival was found in greenhouse-grown bare-root seedlings. The introduction of fertilizer to the soil substrate lowered emergence and survival of directly-seeded trees at the mine site and quarry, but increased tree growth at all sites and photosynthetic rate at the quarry. However, use of fertilizer resulted in a more negative water potential at the mine site and higher transpiration rate, potentially increasing moisture stress and demand. Increased seed survival, growth, and water status can be accomplished through the use of Terra-Sorb, but only in direct seeded trees on sites with potentially deficient plant-available water. Native forest soil can increase survival in both direct seeded and bare-root planted trees. However, more research is needed on the benefits of native forest soil, as growth and physiological results conflict. It is recommended that site characterization be performed prior to selection of planting treatments. Results of this study can prove beneficial to reclamation specialists with an interest in using mine site reclamation in conjunction with American chestnut restoration.
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Monitoring the Influence of Acid Deposition on Soil and Implications to Forest Health in the Daniel Boone National ForestSanderson, Tyler M 01 January 2014 (has links)
Combustion of fossil fuels has contributed to many environmental problems including acid deposition. The Clean Air Act (CAA) was created to reduce ecological problems by cutting emissions of sulfur and nitrogen. Reduced emissions and rainfall concentrations of acidic ions have been observed since the enactment of the CAA, but soils continue to receive some acid inputs. Soils sensitive to acid deposition have been found to have low pH, a loss of base cations and a shift in the mineral phase controlling the activity of Al3+ and/or SO42-. If inputs continue, soil may be depleted of base cations and saturated with Al and could cause low forest productivity. Soil solutions from lysimeters were taken in the Daniel Boone National Forest to evaluate potential impacts of acid deposition. In addition, tree-ring growth and chemical analysis created a timeline of forest health and ion accumulation. Physicochemical characteristics of the soils revealed that sites were very low in base saturation and pH and high in exchangeable acidity. Soil solution data indicated that sites periodically received high acid inputs leading to saturation of Al in soils and the formation of Al-hydroxy-sulfate minerals. Given these conditions, long-term changes in soil chemistry from acid deposition are acknowledged.
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Invertebrate responses to the effects of thinning and understory burning in a canyon live oak (Quercus Chrysolepis) forest in the San Bernardino Mountains, CaliforniaNarog, Marcia Gay 01 January 1991 (has links)
No description available.
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