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  Partner: UNT Libraries
 Decade: 1990-1999
 Month: December
 Degree Discipline: Environmental Science
 Collection: UNT Theses and Dissertations
Ecological Enhancement of Timber Growth: Applying Compost to Loblolly Pine Plantations

Ecological Enhancement of Timber Growth: Applying Compost to Loblolly Pine Plantations

Access: Use of this item is restricted to the UNT Community.
Date: December 1999
Creator: Stuckey, Harold Troy
Description: This study explored the application of compost onto a small loblolly pine tree forest in northeast Texas. Its purpose was to determine if the application of various amounts of compost would provide for accelerated rates of growth for the trees. Soil parameters were also monitored. A total of 270 trees were planted and studied in a northeast Texas forest ecosystem. Compost rates of 5, 25, and 50 tons per acre with either soil or compost backfill were utilized and compared to a control without compost. Nonparametric and parametric ANOVA and Chi-Square tests were utilized. The results indicated that greater application rates retained greater moisture and higher pH levels in the soil. Compost applications also yielded a greater survival rate as well as larger tree height and diameter when compared to the control. The 25 ton/acre application backfilled in native soil achieved the greatest average in height and diameter when compared to the averages for the control plot. Greater growth differences for the 25S application can be attributed to additional nutrients coupled with a stable pH consistent with native soil acidity.
Contributing Partner: UNT Libraries
Environmental Factors Influencing Chlorophyll-a Concentrations in Lake Texoma

Environmental Factors Influencing Chlorophyll-a Concentrations in Lake Texoma

Date: December 1998
Creator: Gibbs, Jennifer S. (Jennifer Sokolovic)
Description: An analysis of algal biomass measured by chlorophyll-a concentration in Lake Texoma was performed as a part of a monitoring program to develop baseline environmental data in order to detect the potential effects of engineered changes in chloride concentrations in the reservoir. This portion of the research project focused on two main research objectives. The first objective was evaluating the effect of sampling strategy on the ability to adequately reflect standing crop estimates and trends in algal biomass. Two sampling regimes utilizing replication of three versus ten samples were applied and then analyzed using a minimum detectable difference algorithm to determine the necessary magnitude of replication to represent the variation in the metric. Chlorophyll-a distribution was analyzed for zonation patterns expected in a river-run reservoir to establish the importance of representative sampling of river, transition and main lake zones of the reservoir for management decisions and trophic characterization.
Contributing Partner: UNT Libraries
Evaluation of the Use of the Bivalves Ischadium recurvum Rafinesque, 1820 and Corbicula fluminea Muller, 1774 as Biological Indicators of Relative Water Quality in Terms of Growth and Upper Temperature Tolerance

Evaluation of the Use of the Bivalves Ischadium recurvum Rafinesque, 1820 and Corbicula fluminea Muller, 1774 as Biological Indicators of Relative Water Quality in Terms of Growth and Upper Temperature Tolerance

Date: December 1997
Creator: Hemming, Jon Michael
Description: Growth of mussels under laboratory conditions was examined under various food regimes in different water types and temperatures. Growth was less than would be useful as an indicator and comparisons with field exposures were of minimal value. The effects of organophosphates on bivalves were examined via toxicity tests, tissue concentration, and by controlling exposure through the use of physical constraints. Upper temperature tolerance of both bivalve species was examined with respect to different acclimation temperatures and organophosphate exposures. Deviations from control exposures occurred at some temperatures. Copper effectively lowered the mean heat coma temperatures of C. fluminea at some concentrations, however, chlorine exposures did not alter heat coma temperature.
Contributing Partner: UNT Libraries
The potential of coelomocyte chemotaxis as an immune biomarker in the earthworm, Lumbricus terrestris

The potential of coelomocyte chemotaxis as an immune biomarker in the earthworm, Lumbricus terrestris

Access: Use of this item is restricted to the UNT Community.
Date: December 1999
Creator: Mota, Jennifer A.
Description: Coelomocyte migration responses, both random and chemotatic, were examined in the earthworm Lumbricus terrestris. Coelomocyte random migration patterns towards non-stimulatory, non-chemotatic solutions were described. Migration responses to immunostimulatory agents lipopolysaccharides (LPS), N-formly-methionyl-leucyl-phenylalanine (FMLP), sheep erythrocytes, Saccharomyces cerevisiae, Aeromonas hydrophila, Eisenia fetida and Rhabditis pellio were characterized. Chemotaxis was reported to LPS, FMLP, sheep erythrocytes, S. cerivesae and E. fetida. Bio-indicator potential of chemotaxis is discussed relative to variability in migration responses.
Contributing Partner: UNT Libraries
Pretreatment Optimization of Fiberglass Manufacturing Industrial Wastewater

Pretreatment Optimization of Fiberglass Manufacturing Industrial Wastewater

Date: December 1998
Creator: Dragoo, Ron
Description: Wastewater effluent produced in the fiberglass manufacturing industry contains a significant amount of total suspended solids. Environmental regulations require pretreatment of effluent before it is discharged to the municipal wastewater treatment plant. Chemical precipitation by coagulation and flocculation is the method of pretreatment used at the Vetrotex CertainTeed Corporation (VCT). A treatability study was conducted to determine conditions at which the VCT Wastewater Pretreatment Plant could operate to consistently achieve a total suspended solids concentration ≤ 200-mg/L. Jar tests varied pH, polymer dosage, and ferric sulfate dosage. Total suspended solids and turbidity were measured to evaluate treatment performance. The data were used to determine an optimum set of conditions under project guidelines. Of twelve polymers screened, BPL 594 was selected as the most effective polymer. For cost efficiency in the wastewater pretreatment operation, recommendations suggested that treatment chemical injection be electronically controlled according to turbidity of the treated effluent.
Contributing Partner: UNT Libraries