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Climate change has altered and will continue to alter the hydrologic systems, Pacific salmon habitat, and survival of salmon in the Nooksack River watershed. Past and future climate change in combination with legacy impacts from forest practices and land use will continue to greatly reduce salmon stocks in the River. Tribal groups are dependent on Pacific salmon for cultural, heritage, subsistence, and commercial uses, and continued climate change will threaten the ability of tribal members to harvest salmon. Tribes are place-based and cannot move to where salmon will survive in the face of climate change. The purpose of this project is to evaluate the effect of climate change on glacier ablation and Nooksack River...
Although ?70 dams have been decommissioned in Wisconsin over the past 30 y, little is known about the physical and ecological effects of dam removal on riverine ecosystems. The purpose of our study was to document changes in channel form and macroinvertebrate assemblages following the removal of a low-head, run-of-river dam from the Baraboo River,Wisconsin, in January 2000. We surveyed cross sections and collected benthic macroinvertebrate samples in 6 reaches (an upstream reference reach, reaches immediately above and below the dam that was to be removed, and sequential unimpounded and impounded reaches further downstream) in a multiple-dam sys- tem. Surveys were conducted in December 1999, before dam removal,...
A slow draining reservoir on the U.S. East Coast was monitored to identify the processes governing channel evolution upstream of a dam removal. Channel evolution was documented through cross section surveys, sediment size analysis, discharge measurements, and visual assessments of vegetative growth. The reservoir drained slowly, allowing for an analysis of channel evolution and identification of the morphometric parameters defining the path and time required for a channel to reach dynamic equilibrium. Channel evolution was a multidirectional process, and evolving channel reaches actively migrated laterally while alternating between aggradation and degradation. Channel formation was dominated primarily by the hydrologic...
Kentchurch Weir, a low-head weir on the river Monnow, Wales, was demolished in August 2011, releasing a sediment wave that had formed behind the structure for at least a century. We surveyed channel topography and bed-material composition through a 1.5-km long reach prior to weir removal and then periodically over a 2-year period. The fill material was finer than the ambient bed material with all particles mobilized by bankfull flows. Rapid degradation of the 1460-m3 sediment fill in the previously impounded reach occurred as bed material appeared to disperse downstream, consistent with other studies of sediment waves in gravel-bed rivers. The riverbed profile was gradually smoothed through the study reach by degrading...
In the late 1970s, the construction of weirs in Norwegian regulated river systems for aesthetic reasons was common. However, today, the focus of river restoration has shifted towards improving biological functionality and biodiversity. In the present study, two weirs, originally built to create a stable water level, were removed on a residual flow reach in a Norwegian regulated river as a measure to restore river connectivity and to re-establish the local population of Atlantic salmon. The removal design was based on hydraulic modelling, and biological monitoring was implemented before and after the weir removal to evaluate the biological response to weir removal. The results demonstrated that salmon spawning sites...
This database is the result of an extensive literature search aimed at identifying documents relevant to the emerging field of dam removal science. In total the database contains 179 citations that contain empirical monitoring information associated with 130 different dam removals across the United States and abroad. Data includes publications through 2014 and supplemented with the U.S. Army Corps of Engineers National Inventory of Dams database, U.S. Geological Survey National Water Information System and aerial photos to estimate locations when coordinates were not provided. Publications were located using the Web of Science, Google Scholar, and Clearinghouse for Dam Removal Information.
In the past two decades, major flood events have occurred on the lower Colorado River, a dramatic shift from the low flows and moderate floods associated with prior decades of river regulation. This study uses repeat aerial photography and Geographic Information System analysis to examine the planform channel response of the upper Colorado River delta (limitrophe reach) to this recently altered hydrology. Results indicate that channel contraction has been the dominant planform process in recent decades, but periodic floods resulted in channel expansion (1981–1988; 1997–2000) or likely reduced the channel contraction measured between successive aerial photographs (1976–1981; 1988–1994). Sinuosity adjustments...
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River systems in Central Asia have been well-studied by scientists in the Former Soviet Union (FSU), but their work has been largely inaccessible to English-speaking North American scientists. Like their North American counterparts, rivers and associated vegetation and wildlife in Central Asia have undergone tremendous change as a result of water management, agriculture and grazing. Important applied aspects of studies of Central Asian systems include the ecology of species native to Central Asia but invasive in North America (e.g., tamarisk, Russian-olive), and riparian restoration approaches (technology transfer from the U.S. to FSU). The objective of this task is to develop and edit a book on riparian ecosystems...
Small-bodied, riverine minnows that historically characterized fish assemblages of Great Plains rivers in North America have declined because of river fragmentation, dewatering, river channel degradation, river salinization and nonnative species introductions. The Pecos bluntnose shiner Notropis simus pecosensis, a member of this guild, persists in one segment of the Pecos River, New Mexico, USA. We characterized habitat associations for the species at two spatial scales. In general, N. s. pecosensis associated with fluvial habitats, but velocity association depended on body size, with larger individuals using swifter habitats. All N. s. pecosensis associated with relatively low depths (3–51 cm), which were most...
Straightened channels and altered and drained adjacent riparian wetlands have adversely impacted streams and rivers throughout the US Midwest. This research investigated the biological connection and water quality of a 0.07 ha diversion wetland and adjacent stream at the Olentangy River Wetland Research Park in central Ohio. Before the flowthrough conditions were established, we demonstrated with mark and recapture techniques that the wetland already was a biorefuge for fish under extreme conditions; two species (Centrarchidae) captured in the stream before a total drawdown of the stream were found in the wetland a year later. In addition, water at the bottom remained at around 4 °C over the winter likely due to...
Alteration of natural flow regimes by river regulation affects fish distribution and assemblage structure, but causative pathways are not always direct and may go unrecognized. The Colorado River population of the endangered Colorado pikeminnow, Ptychocheilus lucius, suffers from low rates of recruitment and reduced carrying capacity. We hypothesized that availability of prey fish for this large-bodied native piscivore may, in part, be limited by reduced standing crops of periphyton and macroinvertebrates resulting from accumulation of fine sediment in the riverbed. We stratified the 373-km-long study area into 11 strata and sampled various physical and biological parameters in runs and riffles of three randomly...
Billions of dollars are being spent in the United States to restore rivers to a desired, yet often unknown, reference condition. In lieu of a known reference, practitioners typically assume the paradigm of a connected watercourse. Geological and ecological processes, however, create patchy and discontinuous fluvial systems. One of these processes, dam building by North American beavers (Castor canadensis), generated discontinuities throughout precolonial river systems of northern North America. Under modern conditions, beaver dams create dynamic sequences of ponds and wet meadows among free-flowing segments. One beaver impoundment alone can exceed 1000 meters along the river, flood the valley laterally, and fundamentally...
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The North Fork of the Virgin River, which flows through Zion National Park, was channelized in the early 1900s to protect the newly built (and now historic) road and Zion Lodge situated along the river. Wire caging filled with rocks (revetments) were installed, which stabilized and heightened the river's banks. Although the effort has been successful in preventing flooding, channelization has had ecological repercussions. Historically, cottonwood and willow forest dominated the canyon floor, providing habitat and forage to native fauna and important aesthetic values to humans. Today, the forest is composed solely of aging trees, as natural flood processes that supported phreatophyte seedling establishment no longer...


    map background search result map search result map Test Riparian Revegetation Methods along the Virgin River, Zion National Park Riparian Ecosystems of Central Asia Climate Change Impacts on Nooksack River Hydrology, Salmon Fish Vulnerability Assessment, and River Habitat Restoration/Adaptation Planning Climate Change Impacts on Nooksack River Hydrology, Salmon Fish Vulnerability Assessment, and River Habitat Restoration/Adaptation Planning Test Riparian Revegetation Methods along the Virgin River, Zion National Park Riparian Ecosystems of Central Asia