You limited your search to:
Partner:
UNT Libraries
Department:
Department of Biology
Degree Level:
Master's
Collection:
Environmental Policy Collection
Integration of field-based analysis of plant community dynamics with quantitative analysis of landscape change in the Ray Roberts Lake area, 19871997
Date: May 2000
Creator: McDonough, Theresa J.
Description: This study focused on the effectiveness of integrating traditional plant community analyses with landscape ecological analyses based on remotely sensed data. A temporal analysis of plant community diversity was conducted for major plant communities of the Ray Roberts Lake area using transect monitoring data collected between 1987 and 1997. Landscape analyses were performed with FRAGSTATS*ARC using classified SPOT satellite imagery for 1987 and 1997. Although the methodology developed in this work was exploratory, it was found that characterizing the dynamics of major plant communities in the study area produced a more effective and insightful analysis of Ray Roberts Lake area landscape dynamics.
Contributing Partner: UNT Libraries
Permallink:digital.library.unt.edu/ark:/67531/metadc2515/
Laboratory and field studies of cadmium effects on Hyalella azteca in effluent dominated systems.
Date: August 2003
Creator: Stanley, Jacob K.
Description: Laboratory single-species toxicity tests are used to assess the effects of contaminants on aquatic biota. Questions remain as to how accurately these controlled toxicity tests predict sitespecific bioavailability and effects of metals. Concurrent 42-day Hyalella azteca exposures were performed with cadmium and final treated municipal effluent in the laboratory and at the University of North Texas Stream Research Facility. Further laboratory testing in reconstituted hard water was also conducted. Endpoints evaluated include survival, growth, reproduction, and Cd body burden. My results demonstrate that laboratory toxicity tests may overestimate toxicity responses to cadmium when compared to effluent dominated stream exposures. Discrepancies between endpoints in the three tests likely resulted from increased food sources and decreased cadmium bioavailability in stream mesocosms
Contributing Partner: UNT Libraries
Permallink:digital.library.unt.edu/ark:/67531/metadc4291/
Managing Cattail (Typha latifolia) Growth in Wetland Systems
Date: August 2002
Creator: Sharp, Jessica Little
Description: Nutrient availability, water depth, competition, and soil management effects on cattail (Typha latifolia) growth in wetland systems were examined. Soluble reactive phosphorous (SRP), nitrate-nitrogen (NO3-N), and ammonia-nitrogen (NH3-N) removals were tested at a constructed wetland receiving municipal wastewater effluent. Over all, no significant differences in nutrients occurred between diverse planted and cattail areas. T. latifolia seeds, under the canopy of Eleochoris macrostachya, had low seed germination. Established stands of emergent vegetation can prevent cattail colonization and spread. Germination of T. latifolia at various water depths was tested, and depth impacts on cattail seedling growth and survival were ascertained using various moist soil management techniques in three ponds. Water levels at 0cm and >40cm can adversely impact cattail establishment.
Contributing Partner: UNT Libraries
Permallink:digital.library.unt.edu/ark:/67531/metadc3210/