Pre-impoundment Environmental Study of Ray Roberts Lake

Pre-impoundment Environmental Study of Ray Roberts Lake

Date: May 1988
Creator: University of North Texas. Institute of Applied Sciences.
Description: "This report presents the results of the pre-impoundment investigations" of Ray Roberts Lake. The purpose of the study is "to improve understanding of the impact of [U.S. Army Corps of Engineers] water resource projects, to provide the basis for evaluating the projects' effects on fish and wildlife resources, and to provide the opportunity for better planning and development of water resource projects and natural resource management" in the Lake Ray Roberts area, located in Denton County, Texas (p. 3).
Contributing Partner: UNT Institute of Applied Sciences
Post-impoundment Study of Ray Roberts Lake Year-Six

Post-impoundment Study of Ray Roberts Lake Year-Six

Date: December 1995
Creator: University of North Texas. Institute of Applied Sciences.
Description: "This report presents the results of investigations conducted six years following the impoundment of Ray Roberts Lake." The purpose of the study is "to improve understanding of the impact of [U.S. Army Corps of Engineers] water resource projects, to provide the basis for evaluating the projects' effects on fish and wildlife resources, and to provide the opportunity for better planning and development of water resource projects and natural resource management" in the Lake Ray Roberts area, located in Denton County, Texas (p. 3).
Contributing Partner: UNT Institute of Applied Sciences
Ecological Studies of the Hudson River Near Indian Point

Ecological Studies of the Hudson River Near Indian Point

Date: April 1971
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Description: "The general purpose of [this study is] to determine the ecological responses of the [Hudson] River to various classes of potential pollutants, so that the discharge of waste heat and radionuclides from the Indian Point Power Plant can be evaluated in context with these" (p. 1).
Contributing Partner: UNT Libraries
Spatial and Temporal Influences of Water Quality on Zooplankton in Lake Texoma

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

Date: May 2000
Creator: Franks, Jessica L.
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 ...
Contributing Partner: UNT Libraries
Ultraviolet Radiation Tolerance in High Elevation Copepods from the Rocky Mountains of Colorado, USA

Ultraviolet Radiation Tolerance in High Elevation Copepods from the Rocky Mountains of Colorado, USA

Date: December 2011
Creator: Hudelson, Karista
Description: Copepods in high elevation lakes and ponds in Colorado are exposed to significant levels of ultraviolet radiation (UV), necessitating development of UV avoidance behavior and photoprotective physiological adaptations. The copepods are brightly pigmented due to accumulation of astaxanthin, a carotenoid which has photoprotective and antioxidant properties. Astaxanthin interacts with a crustacyanin-like protein, shifting its absorbance from 473 nm (hydrophobic free form, appears red) to 632 nm (protein-bound complex, appears blue). In six sites in Colorado, habitat-specific coloration patterns related to carotenoprotein complex have been observed. The objective of this study was to determine whether pigment accumulation or carotenoprotein expression has a greater effect on resistance to UV exposure. For each site, copepod tolerance to UV was assessed by survivorship during UV exposure trials. Average UV exposure was determined for each habitat. Astaxanthin profiles were generated for copepods in each site. Ability to withstand UV exposure during exposure trials was significantly different between color morphs (p < 0.0001). Red copepods were found to tolerate 2-fold greater levels of UVB than blue or mixed copepods. Additionally, red copepods have much higher levels of total astaxanthin than blue or mixed copepods (p < 0.0001) and receive a higher daily UV dose (p < ...
Contributing Partner: UNT Libraries
Marine Ecosystems and Global Change

Marine Ecosystems and Global Change

Date: 2003
Creator: Global Ocean Ecosystem Dynamics Project (GLOBEC)
Description: The ocean is a vital component of the metabolism of the Earth and plays a key role in global change. In fact, the oceans cover so much of the Earth's surface that our planet has been described as the Water Planet, and it could be argued that its most extensive ecosystems are marine. Marine ecosystems are inextricably involved in the physical, chemical, biological and societal processes of global change. It is impossible to describe and understand the Earth system without understanding the ocean, the special characteristics of the environment that it provides for life, the changes that it is undergoing and the manner in which these changes interact with the total Earth System. Understanding the functioning of marine ecosystems and how they respond to global change is also essential in order to effectively manage global marine living resources, such as fisheries. The GLOBEC project is an international response to the need to understand how global change will affect the abundance, diversity and productivity of marine populations, from zooplankton to fish, that comprise a major component of oceanic ecosystems. GLOBEC's goal is to advance our understanding of the structure and functioning of such ecosystems, their major subsystems, and responses to physical ...
Contributing Partner: UNT Libraries
Global Ocean Ecosystem Dynamics (GLOBEC) Science Plan

Global Ocean Ecosystem Dynamics (GLOBEC) Science Plan

Date: 1997
Creator: Global Ocean Ecosystem Dynamics (GLOBEC)
Description: Human population and associated industrial activities continue to increase rapidly, and have reached levels that put the environment under stress in many areas of the world. In addition natural fluctuations of the Earth's physical and biological systems, often occur in time frames that are not readily evident to man. Such fluctuations cause additional stress on the environment, and can result in changes that impact society in terms of diminished availability of clean water, unspoiled land and natural vegetation, minerals, fish stocks, and clean air. Human societies are making a rapidly increasing number of policy and management decisions that attempt to allow both for natural fluctuations and to limit or modify human impact. Such decisions are often ineffective, as a result of economic, political and social constraints, and inadequate understanding of the interactions between human activities and natural responses. Improved understanding of such issues is important in its own right, and will contribute to ameliorating economic, political and social constraints. Developing improved understanding of environmental change is within the realm of the natural sciences and is being addressed by the International Geosphere-Biosphere Programme (IGBP) and other programmes concerned with describing and understanding the Earth System. Natural variability, occurring over a variety ...
Contributing Partner: UNT Libraries
A Net Plankton Survey of a Small Perennial Pond

A Net Plankton Survey of a Small Perennial Pond

Date: August 1940
Creator: Legett, Jesse Harrison
Description: This thesis resulted from an examination of Lake Worth plankton in comparison to plankton found in similar bodies of water throughout the United States.
Contributing Partner: UNT Libraries
Post-impoundment Study of Ray Roberts Lake Year-Ten

Post-impoundment Study of Ray Roberts Lake Year-Ten

Date: December 1999
Creator: University of North Texas. Institute of Applied Sciences.
Description: "This report is the final chapter of a long-term project to assess the environmental impacts associated with the construction and operation of Ray Roberts Lake during its first ten years" (p. ii). The purpose of the study is "to improve understanding of the impact of [U.S. Army Corps of Engineers] water resource projects, to provide the basis for evaluating the projects' effects on fish and wildlife resources, and to provide the opportunity for better planning and development of water resource projects and natural resource management" in the Lake Ray Roberts area, located in Denton County, Texas (p. 3).
Contributing Partner: UNT Institute of Applied Sciences
Pre-impoundment Environmental Study of Ray Roberts Lake

Pre-impoundment Environmental Study of Ray Roberts Lake

Date: December 1987
Creator: University of North Texas. Institute of Applied Sciences.
Description: "This report presents the results of the pre-impoundment investigations" of Ray Roberts Lake. The purpose of the study is "to improve understanding of the impact of [U.S. Army Corps of Engineers] water resource projects, to provide the basis for evaluating the projects' effects on fish and wildlife resources, and to provide the opportunity for better planning and development of water resource projects and natural resource management" in the Lake Ray Roberts area, located in Denton County, Texas (p. 3).
Contributing Partner: UNT Institute of Applied Sciences