Author: Peter J. Pfaff
Publisher:
ISBN:
Category : Colorado River Watershed (Tex.)
Languages : en
Pages : 140
Book Description
Fish communities are distributed heterogeneously within river basins. Heterogeneity is attributed to a number of physical, chemical, and biological processes. Among river basins that traverse a diversity of surficial geologies, physical and chemical properties of surficial geologies influence stream characteristics and regional aquatic communities. Likewise, stream characteristics and aquatic communities of distinct surficial geologies (i.e., georegions) can respond differently to anthropogenic stressors. Purposes of this study were to assess the influence of surficial geologies (i.e., georegions) on stream characteristics and fish communities in the Colorado River basin of Texas, a representative western gulf slope basin of southcentral USA, and determine if anthropogenic stressors differentially affect fish communities by georegion. Using measures of discrete (i.e., georegions, stream type) and continuous (e.g., stream order, distance from river mouth) community variation (i.e., spatial delineations), I found that georegion, stream type, stream order, and distance from mouth distinguished stream characteristic types within the basin, but only georegion explained a significant portion (41%) of the fish community variation. Using fish community changes between time periods (1933 to 1980; 1981 to 2018), which generally corresponds with pre- and post- dam constructions within the basin, I found that anthropogenic flow alterations had more of an effect on fish communities in some georegions than others. My findings support the concept of georegions having a hierarchical influence on stream characteristics and aquatic community heterogeneity within a basin, and that anthropogenic modifications can differentially affect aquatic communities, depending on factors associated with georegions and stream characteristics. Potential benefits of this work include understanding factors influencing the heterogeneity in aquatic communities and the role of anthropogenic stressors across georegions (e.g., prairie streams, karst terrains, lowland coastal rivers) within and outside the western gulf slope basins.
Influence of Surface and Near-surface Geology on Fish Assemblages in the Colorado River Basin of Texas
Author: Peter J. Pfaff
Publisher:
ISBN:
Category : Colorado River Watershed (Tex.)
Languages : en
Pages : 140
Book Description
Fish communities are distributed heterogeneously within river basins. Heterogeneity is attributed to a number of physical, chemical, and biological processes. Among river basins that traverse a diversity of surficial geologies, physical and chemical properties of surficial geologies influence stream characteristics and regional aquatic communities. Likewise, stream characteristics and aquatic communities of distinct surficial geologies (i.e., georegions) can respond differently to anthropogenic stressors. Purposes of this study were to assess the influence of surficial geologies (i.e., georegions) on stream characteristics and fish communities in the Colorado River basin of Texas, a representative western gulf slope basin of southcentral USA, and determine if anthropogenic stressors differentially affect fish communities by georegion. Using measures of discrete (i.e., georegions, stream type) and continuous (e.g., stream order, distance from river mouth) community variation (i.e., spatial delineations), I found that georegion, stream type, stream order, and distance from mouth distinguished stream characteristic types within the basin, but only georegion explained a significant portion (41%) of the fish community variation. Using fish community changes between time periods (1933 to 1980; 1981 to 2018), which generally corresponds with pre- and post- dam constructions within the basin, I found that anthropogenic flow alterations had more of an effect on fish communities in some georegions than others. My findings support the concept of georegions having a hierarchical influence on stream characteristics and aquatic community heterogeneity within a basin, and that anthropogenic modifications can differentially affect aquatic communities, depending on factors associated with georegions and stream characteristics. Potential benefits of this work include understanding factors influencing the heterogeneity in aquatic communities and the role of anthropogenic stressors across georegions (e.g., prairie streams, karst terrains, lowland coastal rivers) within and outside the western gulf slope basins.
Publisher:
ISBN:
Category : Colorado River Watershed (Tex.)
Languages : en
Pages : 140
Book Description
Fish communities are distributed heterogeneously within river basins. Heterogeneity is attributed to a number of physical, chemical, and biological processes. Among river basins that traverse a diversity of surficial geologies, physical and chemical properties of surficial geologies influence stream characteristics and regional aquatic communities. Likewise, stream characteristics and aquatic communities of distinct surficial geologies (i.e., georegions) can respond differently to anthropogenic stressors. Purposes of this study were to assess the influence of surficial geologies (i.e., georegions) on stream characteristics and fish communities in the Colorado River basin of Texas, a representative western gulf slope basin of southcentral USA, and determine if anthropogenic stressors differentially affect fish communities by georegion. Using measures of discrete (i.e., georegions, stream type) and continuous (e.g., stream order, distance from river mouth) community variation (i.e., spatial delineations), I found that georegion, stream type, stream order, and distance from mouth distinguished stream characteristic types within the basin, but only georegion explained a significant portion (41%) of the fish community variation. Using fish community changes between time periods (1933 to 1980; 1981 to 2018), which generally corresponds with pre- and post- dam constructions within the basin, I found that anthropogenic flow alterations had more of an effect on fish communities in some georegions than others. My findings support the concept of georegions having a hierarchical influence on stream characteristics and aquatic community heterogeneity within a basin, and that anthropogenic modifications can differentially affect aquatic communities, depending on factors associated with georegions and stream characteristics. Potential benefits of this work include understanding factors influencing the heterogeneity in aquatic communities and the role of anthropogenic stressors across georegions (e.g., prairie streams, karst terrains, lowland coastal rivers) within and outside the western gulf slope basins.
Index of Surface-water Records
Author: Geological Survey (U.S.). Surface Water Branch. Tucson District
Publisher:
ISBN:
Category : Colorado River Watershed (Colo.-Mexico)
Languages : en
Pages : 28
Book Description
Publisher:
ISBN:
Category : Colorado River Watershed (Colo.-Mexico)
Languages : en
Pages : 28
Book Description
Effects of Water Quality and Habitat on Composition of Fish Communities in the Upper Colorado River Basin
Author: Jeffrey R. Deacon
Publisher:
ISBN:
Category : Fish communities
Languages : en
Pages : 6
Book Description
Publisher:
ISBN:
Category : Fish communities
Languages : en
Pages : 6
Book Description
Reconnaissance of the Chemical Quality of Surface Waters of the Colorado River Basin, Texas
Author: Donald K. Leifeste
Publisher:
ISBN:
Category : Water quality
Languages : en
Pages : 92
Book Description
Publisher:
ISBN:
Category : Water quality
Languages : en
Pages : 92
Book Description
Present and Future Surface-water Availability in the Colorado River Basin, Texas
Author: Texas. Department of Water Resources. Planning and Development Division
Publisher:
ISBN:
Category : Colorado River Watershed (Tex.)
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category : Colorado River Watershed (Tex.)
Languages : en
Pages :
Book Description
Selected Water Resources Abstracts
New Publications of the Geological Survey
Author: Geological Survey (U.S.)
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 748
Book Description
Publisher:
ISBN:
Category : Geology
Languages : en
Pages : 748
Book Description
Selected Water Resources Abstracts
Lost, a Desert River and Its Native Fishes
Author: Gordon Mueller
Publisher:
ISBN:
Category : Colorado River (Colo.-Mexico)
Languages : en
Pages : 90
Book Description
The Colorado River had one of the most unique fish communities in the world. Seventy-five percent of those species were found nowhere else in the world. Settlement of the lower basin brought dramatic change to both the river and its native fish. Those changes began more than 120 years ago as settlers began stocking nonnative fishes. By 1930, nonnative fish had spread throughout the lower basin and replaced native communities. All resemblance of historic river conditions faded with the construction of Hoover Dam in 1935 and other large water development projects. Today, few remember what the Colorado River was really like. Seven of the nine mainstream fishes are now Federally-protected as endangered. Federal and state agencies are attempting to recover these fish. However, progress has been frustrated due to the severity of human impact. This report represents testimony, old descriptions, and photographs describing the changes that have taken place in hopes that it will provide managers, biologists, and the interested public a better appreciation of the environment that shaped these unique fish.
Publisher:
ISBN:
Category : Colorado River (Colo.-Mexico)
Languages : en
Pages : 90
Book Description
The Colorado River had one of the most unique fish communities in the world. Seventy-five percent of those species were found nowhere else in the world. Settlement of the lower basin brought dramatic change to both the river and its native fish. Those changes began more than 120 years ago as settlers began stocking nonnative fishes. By 1930, nonnative fish had spread throughout the lower basin and replaced native communities. All resemblance of historic river conditions faded with the construction of Hoover Dam in 1935 and other large water development projects. Today, few remember what the Colorado River was really like. Seven of the nine mainstream fishes are now Federally-protected as endangered. Federal and state agencies are attempting to recover these fish. However, progress has been frustrated due to the severity of human impact. This report represents testimony, old descriptions, and photographs describing the changes that have taken place in hopes that it will provide managers, biologists, and the interested public a better appreciation of the environment that shaped these unique fish.
Quality of Surface Waters of the United States, 1969
Author: Geological Survey (U.S.)
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description