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Spatial and Temporal Influences of Water Quality on Zooplankton in Lake Texoma

Description: Seventy-one aquatic species including the copepodids and nauplii were identified from Lake Texoma from August 1996 to September 1997. Zooplankton community structure, abundance and spatial and temporal distributions were compared among five lake zones delineated a priori based on chloride concentration. The zones, in order of decreasing chloride concentration, are the Red River zone (RRZ), Red river Transition zone (RRTZ), Main Lake zone (MLZ), Washita River Transition zone (WRTZ) and Washita River zone (WRZ). Bray Curtis Similarity Index showed community structure was most similar in the two Red River arm zones, the two Washita River arm zones and the MLZ. Zooplankton abundance was greatest in the Red River arm (312 org/L), intermediate in the Washita River arm (217 org/L) and least in the Main Lake body (103 org/L). A significant increase in the abundance of a deformed rotifer, Keratella cochlearis, was observed mainly in the Red River arm during a second study from March 1999 to June 1999. Seasonal dynamics, rather than spatial dynamics, were more important in structuring the zooplankton community, especially in the two river arms. Spatial variance was solely attributed to station and zone effects independent of time for a few crustacean species and many of the water quality parameters supporting the presence of longitudinal gradients of differing water quality. Three independent models (Red River arm, Washita River arm, Main Lake body) rather than a single model for the entire reservoir, best describe patterns in the zooplankton community and its relationship to seasonal, physical and chemical factors. Statistical power, sample size and taxonomic resolution were examined. When monitoring seasonal and annuals trends in abundance, the greatest statistical power was achieved by analyzing count data at taxonomic levels above genus. Taxonomic sufficiency was assessed to determine if costs could be reduced for zooplankton identifications. For water quality monitoring ...
Date: May 2000
Creator: Franks, Jessica L.

Life History and Case Building Behaviors of Phylloicus ornatus (Banks) (Trichoptera: Calamoceratidae) In Two Spring Fed Tributaries in the Central Edwards Plateau Bioregion of Texas

Description: The life history and case-making behaviors of Phylloicus ornatus from two springfed first order streams in the Edwards Plateau Bioregion of Texas were studied from January 1998 to November 1999. Field larval, pupal and adult samples and laboratory rearings indicated a multivoltine cycle. First instars differ from late instars in number of labral setae and in having a unique spur-like claw on each lateral hump. Larval development was asynchronous with second through fifth instars and pupae present most months. First instars were present April through July, October and November. Case making of first instar and case reconstruction of later instars extracted from their cases was documented by videophotography.
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Date: August 2000
Creator: Norwood, James Christopher

A Quantitative and Qualitative Bacterial Analysis of Pecan Creek

Description: Since Pecan Creek receives sewage wastes from an obviously inadequate disposal system, it seemed possible that it could receive pathogenic bacteria. The fact that these might be present in numbers sufficient to cause epidemics, provided the proper natural vectors were present, stimulated an interest in and the pursuance of this study.
Date: 1946
Creator: Cook, Vernice

Food Habit Analysis of the Two Species of Texas Crappie

Description: This study is based upon information taken from stomach analysis of 302 black crappie and 561 white crappie; the following data will be presented: 1. Food of adults and fingerlings; 2. Diet variation in relation to food availability; 3. Seasonal variation of feeding habits; 4. Diet variation in relation to size of crappie. Collections were made from ten lakes located in North, East, Central, and South Texas.
Date: 1941
Creator: Mitchell Glenn C.

The Phototropic Properties of Lactuca Ludoviciana (Nutt.) DC. and Silphium Laciniatum L.

Description: This paper deals with certain phases of phototropic properties of two exceptional plants, the pertinent behavior of each being decidedly individualistic and in remarkable contrast to that of herbaceous plants in general. The prickly lettuce, Lactuca ludoviciana (Nutt.) DC. and the rosinweed, Silphium laciniatum L., two common Denton County, Texas, plants, have been selected for this study.
Date: 1941
Creator: Neal, George C.

The Taxonomic Significance of the Foliar Epidermal Hairs of Several Families of Dicotyledons

Description: The present investigation deals with the study of non-glandular epidermal hairs from the leaves of two hundred representative dicotyledons of forty-eight families in the Central North Texas area. Special attention has been given to the Compositae and Leguminosae in an effort to find a possible correlation between epidermal hair morphology and the taxonomic position of the plants concerned.
Date: 1945
Creator: McCarty, Faye A.

Seasonal Variations in Microflora of Four Denton County, Texas, Clay Soils

Description: This investigation has for its aim the confirmation of the correlation between soil moisture and the microflora of soils, and a lesser relation between the soil temperature and the microflora. The soils used in this study are typical clay soils of Denton County, Texas. The samples were taken from virgin pasture lands and analyses made monthly or semimonthly. The wide seasonal variation of temperature and rainfall afford a good opportunity for this study.
Date: 1941
Creator: Manire, Philip

Sanitary Aspects of the Swimming Pool of North Texas State Teachers College, Denton, Texas

Description: This investigation was conducted in order to show that insanitary conditions may exist in the swimming pool at North Texas State Teachers College provided the proper precautions are not taken; and, in contrast that this pool can be sanitary and entirely safe when operated and used according to the necessary sanitary specifications.
Date: 1943
Creator: Self, Louise

The Spermatophytes of Tarrant County, Texas

Description: The problem consisted of thoroughly exploring Tarrant County, Texas, in an attempt to collect and study critically as many species of Spermatophytes as possible. In addition a thorough examination was made of herbarium specimens assembled from the region by other botanists.
Date: 1943
Creator: McCart, William Larrey