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The Relation Between Carbon Assimilation and Biomass Dynamics in a Phytoplankton Community

Description: Production dynamics in the phytoplankton community of a mesotrophic Texas reservoir were measured weekly over a four month period using 14C incubation and ATP assay methodologies. Assimilation values of 14C ranged from 0.2 to 45 ug C 1 hr1 - . Significant positive and occasionally negative changes in biomass (i.e. viable organic carbon) were observed in short term (4 hr) in situ incubations juxtapo-sitioned with the 14C experiments; viable organic carbon production, estimated with the ATP assay, ranged from -25 to +50 ug C 1l1hr1. Carbon assimilation and biomass changes did not correlate in either short term (4-5 hr.) or over the study period (6 months). However, weekly biomass trends were predicted by relative positive or negative biomass changes in the short term incubations. Biomass measurements gave a more sensitive insight into production dynamics in the phytoplankton community than did carbon assimilation measurements.
Date: December 1977
Creator: Wilcox, Douglas P.
Partner: UNT Libraries

Dry season limnological conditions and basin geology exhibit complex relationships with δ¹³C and δ¹⁵N of carbon sources in four Neotropical floodplains

Description: This article assesses the potential for basin geology and local limnological conditions to predict stable carbon and nitrogen isotope values of six carbon sources at multiple locations in four Neotropical floodplain ecosystems (Paranaá , Pantanal, Araguaia, and Amazon).
Date: March 30, 2017
Creator: Alves, Gustavo H. Zaia; Hoeinghaus, David; Manetta, Gislaine I. & Benedito, Evanilde
Partner: UNT College of Arts and Sciences

Pre-impoundment Environmental Study of Ray Roberts Lake

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).
Date: May 1988
Creator: University of North Texas. Institute of Applied Sciences.
Partner: UNT Institute of Applied Sciences

Post-impoundment Study of Ray Roberts Lake Year-Six

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).
Date: December 1995
Creator: University of North Texas. Institute of Applied Sciences.
Partner: UNT Institute of Applied Sciences

Effects of Entrainment by the Indian Point Power Plant on Biota in the Hudson River Estuary, August 1976

Description: "This report presents the final results of studies conducted at Indian Point during 1973 using the full complement of available striped bass ichthyoplankton data. These procedures were undertaken in order to present data for river and plant comparisons in the proper perspective of time and space" (p. ii).
Date: August 1976
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Libraries

Ecological Studies of the Hudson River Near Indian Point

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).
Date: April 1971
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Libraries

Effects of Entrainment by the Indian Point Power Plant on Biota in the Hudson River Estuary, 1973

Description: "This report summarizes the progress of studies conducted in 1973 to determine the effects on Hudson River organisms of entrainment by the Indian Point nuclear power station" with emphasis "on the potential effects of entrainment on organisms passing through the plant's condenser cooling system" (p. xxi).
Date: September 1974
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Institute of Applied Sciences

Effects of Entrainment by the Indian Point Power Plant on Biota in the Hudson River Estuary, March 1975

Description: "The data presented in this report represent an analysis of the abundance of four life-history stages of striped bass collected in the Hudson River at Indian Point and the intakes and discharge canal at the Indian Point Power Station" (p. 54).
Date: March 1975
Creator: New York University. Medical Center. Institute of Environmental Medicine.
Partner: UNT Libraries

Global Ocean Ecosystem Dynamics (GLOBEC) Science Plan

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 of time scales, dominates the health of complex marine ecosystems, regardless of fishing or other environmental pressure. We are only now beginning to compile quantitative documentation of such variability, and consequently our knowledge concerning its causes remains at the level of hypotheses. Understanding of the role of variability in the functioning of marine ecosystems is essential if we are to effectively manage global marine living resources such as fisheries during this period of tremendously increased human impact, and concurrent dependence, on these resources.
Date: 1997
Creator: Global Ocean Ecosystem Dynamics (GLOBEC)
Partner: UNT Libraries

Post-impoundment Study of Ray Roberts Lake Year-Ten

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).
Date: December 1999
Creator: University of North Texas. Institute of Applied Sciences.
Partner: UNT Institute of Applied Sciences

Pre-impoundment Environmental Study of Ray Roberts Lake

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).
Date: December 1987
Creator: University of North Texas. Institute of Applied Sciences.
Partner: UNT Institute of Applied Sciences

Limitation of Primary Productivity in a Southwestern Reservoir Due to Thermal Pollution

Description: Evidence is presented to support the conclusions that (1) North Lake reservoir is less productive, contains lower standing crops of phytoplankton and total organic carbon than other local reservoirs; (2) that neither the phytoplankton nor their instantaneously-determined primary productivity was detrimentally affected by the power plant entrainment and (3) that the effect of the power plant is to cause nutrient limitation of the phytoplankton primary productivity by long-term, subtle, thermally-linked nutrient precipitation activities.
Date: August 1977
Creator: Stuart, Tom J.
Location Info:
Partner: UNT Libraries

Preimpoundment Water Quality in the Tioga River Basin, Pennsylvania and New York

Description: Introduction: The U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, and aided by the Susquehanna River Basin Commission, investigated the water quality of the Tioga River basin, Pennsylvania. The study, made from September 1973 to September 1978, was designed to evaluate water quality at various sites prior to impoundment. Results of the investigation will aid the Corps of Engineers in designing the operation of three reservoirs that were in the final stages of construction in late 1979.
Date: March 1981
Creator: Ward, Janice R.
Partner: UNT Libraries Government Documents Department

Primary Productivity by Phytoplankton in the Tidal, Fresh Potomac River, Maryland, May 1980 to August 1981

Description: Purpose and scope: The purpose of this study was to determine primary productivity and respiration of the fresh, tidal Potomac River. The data will be used by the authors and other researchers involved in modelling chemical and biological properties to calculate phytoplankton growth rates. Methods are documented in detail so that the report could serve as a reference. The report covers the period from May 1980 through August 1981. Five stations were selected for study that are representative of biologically important reaches of the fresh, tidal Potomac River.
Date: 1983
Creator: Cohen, R. H. & Pollock, Sheryl O.
Partner: UNT Libraries Government Documents Department