Global ETD Search

11	Shrinking the Janzen-Connell Doughnut: Consequences of an Invasive Multiplier (Microstegium vimineum) on the Mid-canopy in a Mixed Pine-Oak Forest Shaw, Rebekha 04 May 2009 (has links) Introduction of invasive species can alter seed fate predictions made by the Janzen-Connell Escape Hypothesis (JCEH). The JCEH states that there is a suitable region around a plant that is ideal for seed germination, growth, and recruitment. Seeds dispersed too close to the maternal plant are subject to competition from the maternal individual and perhaps density-dependent predation, whereas seeds dispersed further away may end up in suboptimal habitats. Invasive species may change the amount of these suitable habitats for native plants by creating unsuitable light environments and as a result, may influence the size of the ideal recruitment zone surrounding a parent plant. This study examines the extent to which the invasive grass species, Microstegium vimineum, influences recruitment of the understory tree, Cornus florida. In general, M. vimineum was found to reduce both germination and early seedling success and may have significant consequences for future forest structure. Janzen-Connell Escape Hypothesis Microstegium vimineum Cornus florida seed dispersal invasive species Environmental Sciences Physical Sciences and Mathematics
12	SPATIAL AND TEMPORAL PATTERNS OF INVASIVE EXOTIC PLANT SPECIES IN RESPONSE TO TIMBER HARVESTING IN A MIXED MESOPHYTIC FOREST OF EASTERN KENTUCKY Rasp, Benjamin Christopher 01 January 2019 (has links) Invasive exotic species (IES) responses to silvicultural treatments eight years after timber harvesting were examined and compared to one-year post-harvest IES survey in University of Kentucky’s Robinson Forest. The temporal effects of harvesting were further compared between harvested and non-harvested watersheds. Analyses were performed to identify IES spatial distribution and determine the relationships between IES presence and disturbance effects, biological, and environmental characteristics. IES prevalence was higher in the harvested watersheds and was influenced by canopy cover, shrub cover and disturbance proximity. Ailanthus altissima and Microstegium vimineum presence in the study area has decreased over time. Comparing to the 1-yr post-harvest study which only identified direct harvesting effects (e.g. canopy cover and disturbance proximities) as significant predictors, the 8-yr post-harvest survey results suggest that while harvesting effects and disturbance proximity still play an important role, environmental characteristics have also taken precedence in predicting IES presence. Overall IES prevalence has decreased but invasive plant species richness has increased over time. Results indicate that IES eradication may not need to be conducted immediately after harvesting, and when needed, can primarily target IES hotspots where low canopy cover, proximity to disturbance, and southwest facing slopes convene on the landscape. invasive exotic species timber harvesting regeneration Ailanthus altissima Microstegium vimineum temporal dynamics Forest Biology Forest Management Forest Sciences
13	EFFECTS OF TREEFALL GAPS AND SOIL DISTURBANCE ON THE INVASION OF FOUR NON-NATIVE PLANT SPECIES IN A MATURE UPLAND FOREST IN MARYLAND Emsweller, Lauren N. 30 November 2015 (has links) No description available. Botany Ecology
14	The Effect of Silviculture Management on the Spread of Three Invasive Species Redwood, Mame S. 26 July 2012 (has links) No description available. Botany invasive harvest burn spread Microstegium vimineum Ailanthus altissima Alliaria petiolata dormancy germination slope aspect seed survivorship ecology garlic mustard japanese stiltgrass tree of heaven dispersal establishment

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