Actinoplanes Philippinensis: Effect of Carbon Sources on Zoospore Production (open access)

Actinoplanes Philippinensis: Effect of Carbon Sources on Zoospore Production

Actinomycetes are able to utilize a great variety of carbohydrates, like sugar. The particular kind of sugar and its concentration has decisive effect on the growth of microorganisms. The proper nutritional media aids also in the production of spores. Based on this generalization, that the growth and sporulation of microorganisms are greatly influenced by the nature and the concentration of carbohydrates, an attempt has been made to study Actinoplanes philippinensis with respect to this influence.
Date: May 1968
Creator: White, Olivia
System: The UNT Digital Library
A Qualitative Survey of the Airborne Algae, Protozoa, and Bacteria at the Denton Sewage Treatment Plant (open access)

A Qualitative Survey of the Airborne Algae, Protozoa, and Bacteria at the Denton Sewage Treatment Plant

This study had a three-fold purpose. First, it was decided to determine if algae and protozoa were emitted to the air at the Denton sewage treatment plant. The information obtained could be of future importance in the fields of algal and protozoan ecology and public health. Second, it was decided to make a survey of the airborne bacteria at this plant. Some researchers have described bacterial air contamination at similar sewage treatment plants, but the one in Denton has not been studied. Third, it was hoped that in this research some relationships could be found between the bacteria and the algae and protozoa in the air in the vicinity of the sewage aeration basin. It was hypothesized that pathogenic bacteria were carried in the air with these other organisms.
Date: May 1968
Creator: Mahoney, Joseph L.
System: The UNT Digital Library
A Comparison of the Carbon Dioxide and Oxygen Rate of Change Methods for Measuring Primary Productivity (open access)

A Comparison of the Carbon Dioxide and Oxygen Rate of Change Methods for Measuring Primary Productivity

The purpose of this study was to demonstrate the variability of oxygen and carbon dioxide rate of change methods for measuring primary productivity and respiration in an aquatic environment.
Date: May 1969
Creator: Trotter, Dennis M.
System: The UNT Digital Library
Distribution of Phosphates in a Sewage Plant and its Receiving Waters (open access)

Distribution of Phosphates in a Sewage Plant and its Receiving Waters

The purpose of this paper is to detail the distribution and quantity of soluble phosphates in an activated sludge plant, its discharge creek, and receiving reservoir. The resultant analyses and comparison of data should provide some better understanding of the fate of phosphorus in a Southwestern waterway system.
Date: May 1969
Creator: Hansard, John D.
System: The UNT Digital Library
Quantitative Aspects of the Microflora of an Overland Flow Spray Irrigation Sewage Disposal System (open access)

Quantitative Aspects of the Microflora of an Overland Flow Spray Irrigation Sewage Disposal System

It was the purpose of this investigation to attempt to quantitate the microflora of the fields which receive the effluent from the Campbell Soup Plant, Paris, Texas, and to determine whether or not there is a correlation between the numbers and types of organisms present and the efficiency of purification of the system.
Date: May 1969
Creator: Jones, Rebecca
System: The UNT Digital Library
A Study of a Branchiobdellid from Denton County, Texas (open access)

A Study of a Branchiobdellid from Denton County, Texas

In this study, branchiobdellids were collected from crayfish captured from two adjacent sites in Denton County, Texas. Identification of the branchiobdellid, Cambarincola vitrea Ellis, was first made and then work was extended to include several topics of ecological interest.
Date: May 1970
Creator: Koepp, Stephen J.
System: The UNT Digital Library
Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas (open access)

Food Habits and Dietary Overlap of Four Species of Rodents from the Mesquite Plains of Texas

The coexistence of Dipodomys ordii and Perognathus hispidus with Peromyscus maniculatus and Reithrodontomys montanus was studied in a grassland association of central Texas. The food habits of these species were compared with information from habitat vegetation analysis in an effort to determine food selectivity and the amount and importance of niche overlap and competition among these rodents.
Date: May 1972
Creator: Alcoze, Thomas M.
System: The UNT Digital Library
Primary Productivity and Nutrient Relationships in Garza-Little Elm Reservoir (open access)

Primary Productivity and Nutrient Relationships in Garza-Little Elm Reservoir

A large, multi-basin, reservoir (Garza-Little Elm Reservoir) in north central Texas was studied to determine the relative effects of various parameters on primary productivity. The basins were impounded several years apart,thus allowing the influence of age on water chemistry and biota to be considered. Another principal influence on water quality was secondary sewage effluent that entered one basin from a nearby source.
Date: May 1973
Creator: Smith, Jerry Allen
System: The UNT Digital Library
Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX (open access)

Evaluation of a Constructed Wetland to Reduce Toxicity from Diazinon at the Pecan Creek Wastewater Treatment Plant, Denton, TX

The City of Denton Pecan Creek Wastewater Treatment Facility has periodically failed effluent toxicity testing. A Toxicity Identification Evaluation has determined that Diazinon in the effluent is contributing to the observed toxicity. Chlorpyrifos is also implicated as a factor. The City of Denton constructed a half acre experimental wetland to remove Diazinon related toxicity. Results from spiking and microcosm experiments indicate that the wetland can reduce the Diazinon.
Date: May 1996
Creator: Baerenklau, Amy L. (Amy Lyn)
System: The UNT Digital Library
Analysis of Phytoplankton Responses to Water Chemistry Dynamics in a Moderately Eutrophic North Texas Reservoir (open access)

Analysis of Phytoplankton Responses to Water Chemistry Dynamics in a Moderately Eutrophic North Texas Reservoir

Canonical correspondence analysis (CCA) was used to explore relationships between measured environmental variables and in situ phytoplankton communities in a moderately eutrophic North Texas Reservoir.
Date: May 1998
Creator: Banks, Kenneth E. (Kenneth Edward)
System: The UNT Digital Library
Callibaetis Floridanus (Ephemeroptera: Baetidae) Life History and Production in a West Texas Playa (open access)

Callibaetis Floridanus (Ephemeroptera: Baetidae) Life History and Production in a West Texas Playa

A life history study of Callibaetis floridanus was conducted over the wet cycle of a playa on the Southern High Plains of Texas from June through September 1995.
Date: May 1998
Creator: Anderson, Gregory (Gregory Mark)
System: The UNT Digital Library
A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A (open access)

A Comparison of Predicted and Actual Trophic Status of Lake Ray Roberts, Texas Based on Chlorophyll A

Two years before impoundment, the trophic status of Lake Ray Roberts was predicted by applying the total phosphorus input into the Organization for Economic Cooperation and Development (OECD) eutrophication model. Predicted mean summer epilimnetic (MSE) chlorophyll a of Elm Fork arm, Isle duBois arm and Main Body were in the eutrophic category of the OECD model. Observed MSE chlorophyll a two years after impoundment of Elm Fork arm, Isle duBois and Main Body had not reached their predicted means and were at the mesotrophic-eutrophic boundary of the OECD model. Six years after impoundment, observed MSE chlorophyll a for Main Body, was closer to its predicted mean and in the eutrophic category of the OECD model. Six years after impoundment, Elm Fork arm was the most productive area of Lake Ray Roberts. Observed means of chlorophyll a, total phosphates, suspended solids and turbidity were often highest in the Elm Fork arm. Wastewater effluent from Gainesville and Valley View, TX, had an impact on productivity in Elm Fork arm.
Date: May 1999
Creator: Lytle, Lili Lisa
System: The UNT Digital Library
The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment (open access)

The Effects of Organic Surface Amendments on Soil Nutrients and Initial Tree Establishment

This study examined the effects of replicating woodland soil surface horizonation on the nutrient status of underlying soils and the initial establishment and growth of trees. A total of 283 container grown trees were planted in a bufferzone around a future landfill site. Control amendments consisted of an 8 cm layer (0.5 m3) of wood chips applied in a circular area of 4.6 m2 around the trees' planting pit. For the treatment, a 2.5 cm layer of composted biosolids (0.15 m3 or 80 Mg/ha) was applied in a circular area of 4.6 m2 around the trees' planting pit followed by an 8 cm layer (0.5 m3) of wood chips. The results indicate that the replication of woodland soil surface attributes using composted biosolids can significantly improve the nutrient status of underlying soil. Some significant effects were seen under control conditions, too. However, the effects on tree establishment and growth parameters were, for the most part, not statistically significant.
Date: May 1999
Creator: Thuesen, Kevin (Kevin Andrew)
System: The UNT Digital Library