Mid-Columbia Coho Salmon Reintroduction Feasibility Project : Environmental Assessment.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration; Washington (State) Department of Fish and Wildlife; Confederated Tribes and Bands of the Yakama Nation

1999-01-01

Before the Bonneville Power Administration (BPA) decides whether to fund a program to reintroduce coho salmon to mid-Columbia River basin tributaries, research is needed to determine the ecological risks and biological feasibility of such an effort. Since the early 1900s, the native stock of coho has been decimated in the tributaries of the middle reach of the Columbia River. The four Columbia River Treaty Tribes identified coho reintroduction in the mid-Columbia as a priority in the Tribal Restoration Plan. It is a comprehensive plan put forward by the Tribes to restore the Columbia River fisheries. In 1996, the Northwest Power Planning Council (NPPC) recommended the tribal mid-Columbia reintroduction project for funding by BPA. It was identified as one of fifteen high-priority supplementation projects for the Columbia River basin, and was incorporated into the NPPC`s Fish and Wildlife Program. The release of coho from lower Columbia hatcheries into mid-Columbia tributaries is also recognized in the Columbia River Fish Management Plan.

Processesof Tamarix invasion and floodplain development along the lower Green River, Utah.

Science.gov (United States)

Birken, Adam S; Cooper, David J

2006-06-01

Significant ecological, hydrologic, and geomorphic changes have occurred during the 20th century along many large floodplain rivers in the American Southwest. Native Populus forests have declined, while the exotic Eurasian shrub, Tamarix, has proliferated and now dominates most floodplain ecosystems. Photographs from late 19th and early 20th centuries illustrate wide river channels with largely bare in-channel landforms and shrubby higher channel margin floodplains. However, by the mid-20th century, floodplains supporting dense Tamarix stands had expanded, and river channels had narrowed. Along the lower Green River in eastern Utah, the causal mechanism of channel and floodplain changes remains ambiguous due to the confounding effects of climatically driven reductions in flood magnitude, river regulation by Flaming Gorge Dam, and Tamarix invasion. This study addressed whether Tamarix establishment and spread followed climate- or dam-induced reductions in annual peak flows or whether Tamarix was potentially a driver of floodplain changes. We aged 235 Tamarix and 57 Populus individuals, determined the hydrologic and geomorphic processes that controlled recruitment, identified the spatial relationships of germination sites within floodplain stratigraphic transects, and mapped woody riparian vegetation cohorts along three segments of the lower Green River. The oldest Tamarix established along several sampling reaches in 1938, and 1.50-2.25 m of alluvium has accreted above their germination surfaces. Nearly 90% of the Tamarix and Populus samples established during flood years that exceeded the 2.5-year recurrence interval. Recruitment was most common when large floods were followed by years with smaller peak flows. The majority of Tamarix establishment and Green River channel narrowing occurred long before river regulation by Flaming Gorge Dam. Tamarix initially colonized bare instream sand deposits (e.g., islands and bars), and most channel and floodplain changes

Drivers of annual to decadal streamflow variability in the lower Colorado River Basin

Science.gov (United States)

Lambeth-Beagles, R. S.; Troch, P. A.

2010-12-01

The Colorado River is the main water supply to the southwest region. As demand reaches the limit of supply in the southwest it becomes increasingly important to understand the dynamics of streamflow in the Colorado River and in particular the tributaries to the lower Colorado River. Climate change may pose an additional threat to the already-scarce water supply in the southwest. Due to the narrowing margin for error, water managers are keen on extending their ability to predict streamflow volumes on a mid-range to decadal scale. Before a predictive streamflow model can be developed, an understanding of the physical drivers of annual to decadal streamflow variability in the lower Colorado River Basin is needed. This research addresses this need by applying multiple statistical methods to identify trends, patterns and relationships present in streamflow, precipitation and temperature over the past century in four contributing watersheds to the lower Colorado River. The four watersheds selected were the Paria, Little Colorado, Virgin/Muddy, and Bill Williams. Time series data over a common period from 1906-2007 for streamflow, precipitation and temperature were used for the initial analysis. Through statistical analysis the following questions were addressed: 1) are there observable trends and patterns in these variables during the past century and 2) if there are trends or patterns, how are they related to each other? The Mann-Kendall test was used to identify trends in the three variables. Assumptions regarding autocorrelation and persistence in the data were taken into consideration. Kendall’s tau-b test was used to establish association between any found trends in the data. Initial results suggest there are two primary processes occurring. First, statistical analysis reveals significant upward trends in temperatures and downward trends in streamflow. However, there appears to be no trend in precipitation data. These trends in streamflow and temperature speak to

Hydraulic Characteristics of the Lower Snake River During Periods of Juvenile Fall Chinook Migration

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Cook, Chris B.; Dibrani, Berhon; Richmond, Marshall C.; Bleich, Matthew D.; Titzler, P. Scott; Fu, Tao

2006-01-30

This report documents a four-year study to assess hydraulic conditions in the lower Snake River. The work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by the Pacific Northwest National Laboratory. Cold water released from the Dworshak Reservoir hypolimnion during mid- to late-summer months cools the Clearwater River far below equilibrium temperature. The volume of released cold water augments the Clearwater River, and the combined total discharge is on the order of the Snake River discharge when the two rivers meet at their confluence near the upstream edge of Lower Granite Reservoir. With typical temperature differences between the Clearwater and Snake rivers of 10°C or more during July and August, the density difference between the two rivers during summer flow augmentation periods is sufficient to stratify Lower Granite Reservoir as well as the other three reservoirs downstream. Because cooling of the river is desirable for migrating juvenile fall Chinook salmon (Oncorhynchus tshawytscha) during this same time period, the amount of mixing and cold water entrained into Lower Granite Reservoir’s epilimnion at the Clearwater/Snake River confluence is of key biological importance to juvenile fall Chinook salmon. Data collected during this project indicates the three reservoirs downstream of Lower Granite also stratify as direct result of flow augmentation from Dworshak Reservoir. These four lower Snake reservoirs are also heavily influenced by wind forcing at the water’s surface, and during periods of low river discharge, often behave like a two-layer lake. During these periods of stratification, lower river discharge, and wind forcing, the water in the upper layer of the reservoir is held in place or moves slightly upstream. This upper layer is also exposed to surface heating and may warm up to temperatures close to equilibrium temperature. The depth of this upper warm layer and its direction of travel may also be of key

Baseline hydrologic studies in the lower Elwha River prior to dam removal

Science.gov (United States)

Magirl, Christopher S.; Curran, Christopher A.; Sheibley, Rich W.; Warrick, Jonathan A.; Czuba, Jonathan A.; Czuba, Christiana R.; Gendaszek, Andrew S.; Shafroth, Patrick B.; Duda, Jeffrey J.; Foreman, James R.

2011-01-01

After the removal of two large, long‑standing dams on the Elwha River, Washington, the additional load of sediment and wood is expected to affect the hydrology of the lower river, its estuary, and the alluvial aquifer underlying the surrounding flood plain. To better understand the surface-water and groundwater characteristics of the river and estuary before dam removal, several hydrologic data sets were collected and analyzed. An experiment using a dye tracer characterized transient storage, and it was determined that the low‑flow channel of the lower Elwha River was relatively simple; 1–6 percent of the median travel time of dye was attributed to transient‑storage processes. Water data from monitoring wells adjacent to the main‑stem river indicated a strong hydraulic connectivity between stage in the river and groundwater levels in the flood plain. Analysis of temperature data from the monitoring wells showed that changes in the groundwater temperature responded weeks or months after water temperature changed in the river. A seepage investigation indicated that water from the river was moving into the aquifer (losing

Bed Degradation and Sediment Export from the Missouri River after Dam Construction and River Training: Significance to Lower Mississippi River Sediment Loads

Science.gov (United States)

Blum, M. D.; Viparelli, E.; Sulaiman, Z. A.; Pettit, B. S.

2016-12-01

More than 40,000 dams have been constructed in the Mississippi River drainage basin, which has had a dramatic impact on suspended sediment load for the Mississippi delta. The most significant dams were constructed in the 1950s on the Missouri River in South Dakota, after which total suspended loads for the lower Mississippi River, some 2500 km downstream, were cut in half: gauging station data from the Missouri-Mississippi system show significant load reductions immediately after dam closure, followed by a continued downward trend since that time. The delta region is experiencing tremendous land loss in response to acceleration of global sea-level rise, and load reductions of this magnitude may place severe limits on mitigation efforts. Here we examine sediment export from the Missouri system due to bed scour. The US Army Corps of Engineers has compiled changes in river stage at constant discharge for 8 stations between the lowermost dam at Yankton, South Dakota and the Missouri-Mississippi confluence at St. Louis (a distance of 1250 river km), for the period 1930-2010, which we have updated to 2015. These data show two general reaches of significant bed degradation. The first extends from the last major dam at Yankton, South Dakota downstream 300 km to Omaha, Nebraska, where degradation in response to the dam exceeds 3 m. The second reach, with >2.5 m of degradation, occurs in and around Kansas City, Missouri, and has been attributed to river training activities. The reach between Omaha and Kansas City, as well as the lower Missouri below Kansas City, show River due to bed scour following dam construction and river training. This number equates to 20-25 million tons per year, which is sufficient to account for 30% of the total Missouri River load, and 15% of the total post-dam annual sediment load for the lower Mississippi River. For perspective, the quantity of sediment exported from the Missouri River due to bed scour is greater than the total load for all

Compositional Characteristics of Dissolved Organic Matter released from the sediment of Han river in Korea.

Science.gov (United States)

Oh, H.; Choi, J. H.

2017-12-01

The dissolved organic matter (DOM) has variable characteristics depending on the sources. The DOM of a river is affected by rain water, windborne material, surface and groundwater flow, and sediments. In particular, sediments are sources and sinks of nutrients and pollutants in aquatic ecosystems by supplying large amounts of organic matter. The DOM which absorbs ultraviolet and visible light is called colored dissolved organic matter (CDOM). CDOM is responsible for the optical properties of natural waters in several biogeochemical and photochemical processes and absorbs UV-A (315-400 nm) and UV-B (280-315), which are harmful to aquatic ecosystems (Helms et al., 2008). In this study, we investigated the quantity and quality of DOM and CDOM released from the sediments of Han river which was impacted by anthropogenic activities and hydrologic alternation of 4 Major River Restoration Project. The target area of this study is Gangchenbo (GC), Yeojubo (YJ), and Ipobo(IP) of the Han River, Korea. Sediments and water samples were taken on July and August of 2016 and were incubated at 20° up to 7 days. Absorbance was measured with UV-visible spectrophotometer (Libra S32 PC, Biochrom). Fluorescence intensity determined with Fluorescence EEMs (F-7000, Hitachi). Absorbance and fluorescence intensity were used to calculate Specific Ultraviolet Absorbance (SUVA254), Humification index (HIX), Biological index (BIX), Spectral slope (SR) and component analysis. The DOC concentration increased after 3 days of incubation. According to the SUVA254 analysis, the microbial activity is highest in the initial overlying water of IP. HIX have range of 1.35-4.08, and decrease poly aromatic structures of organic matter during incubation. From the results of the BIX, autochthonous organic matter was released from the sediments. In all sites, Humic-like DOM, Microbial humic-like DOM and Protein-like DOM increased significantly between Day 0 and 3(except Humic-like, Microbial humic-like DOM in

Measured and simulated runoff to the lower Charles River, Massachusetts, October 1999-September 2000

Science.gov (United States)

Zarriello, Phillip J.; Barlow, Lora K.

2002-01-01

The lower Charles River, the water body between the Watertown Dam and the New Charles River Dam, is an important recreational resource for the Boston, Massachusetts, metropolitan area, but impaired water quality has affected its use. The goal of making this resource fishable and swimmable requires a better understanding of combined-sewer-overflow discharges, non-combined-sewer-overflow stormwater runoff, and constituent loads. This report documents the modeling effort used to calculate non-combined-sewer-overflow runoff to the lower Charles River. During the 2000 water year, October 1, 1999?September 30, 2000, the U.S. Geological Survey collected precipitation data at Watertown Dam and compiled data from five other precipitation gages in or near the watershed. In addition, surface-water discharge data were collected at eight sites?three relatively homogenous land-use sites, four major tributary sites, and the Charles River at Watertown Dam, which is the divide between the upper and lower watersheds. The precipitation and discharge data were used to run and calibrate Stormwater Management Models developed for the three land-use subbasins (single-family, multi-family, and commercial), and the two tributary subbasins (Laundry and Faneuil Brooks). These calibrated models were used to develop a sixth model to simulate 54 ungaged outfalls to the lower Charles River. Models developed by the U.S. Geological Survey at gaged sites were calibrated with up to 24 storms. Each model was evaluated by comparing simulated discharge against measured discharge for all storms with appreciable precipitation and reliable discharge data. The model-fit statistics indicated that the models generally were well calibrated to peak discharge and runoff volumes. The model fit of the commercial land-use subbasin was not as well calibrated compared to the other models because the measured flows appear to be affected by variable conditions not represented in the model. A separate Stormwater

Research, Monitoring, and Evaluation of Avian Predation on Salmonid Smolts in the Lower and Mid-Columbia River, 2008 Draft Season Summary.

Energy Technology Data Exchange (ETDEWEB)

Roby, Daniel D. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Department of Fisheries and Wildlife, Oregon State University; Collis, Ken [Real Time Research, Inc.; Lyons, Donald E. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University

2009-07-08

predation. Cormorant predation rates in excess of 30%, however, were observed for some groups of hatchery-reared fall Chinook salmon released downstream of Bonneville Dam. Implementation of the federal plan 'Caspian Tern Management to Reduce Predation of Juvenile Salmonids in the Columbia River Estuary' was initiated in 2008 with construction by the Corps of Engineers of two alternative colony sites for Caspian terns in interior Oregon: a 1-acre island on Crump Lake in the Warner Valley and a 1-acre island on Fern Ridge Reservoir near Eugene. We deployed Caspian tern social attraction (decoys and sound systems) on these two islands and monitored for Caspian tern nesting. Caspian terns quickly colonized the Crump Lake tern island; about 430 pairs nested there, including 5 terns that had been banded at the East Sand Island colony in the Columbia River estuary, over 500 km to the northwest. No Caspian terns nested at the Fern Ridge tern island in 2008, but up to 9 Caspian terns were recorded roosting on the island after the nesting season. There were two breeding colonies of Caspian terns on the mid-Columbia River in 2008: (1) about 388 pairs nested at the historical colony on Crescent Island in the McNary Pool and (2) about 100 pairs nested at a relatively new colony site on Rock Island in the John Day Pool. Nesting success at the Crescent Island tern colony was only 0.28 young fledged per breeding pair, the lowest nesting success recorded at that colony since monitoring began in 2000, while only three fledglings were raised at the Rock Island tern colony. The diet of Crescent Island Caspian terns consisted of 68% salmonid smolts; total smolt consumption was estimated at 330,000. Since 2004, total smolt consumption by Crescent Island terns has declined by 34%, due mostly to a decline in colony size, while steelhead consumption has increased 10% during this same period. In 2008, approximately 64,000 steelhead smolts were consumed by Caspian terns nesting at Crescent

Lower Charles River Bathymetry: 108 Years of Fresh Water

Science.gov (United States)

Yoder, M.; Sacarny, M.

2017-12-01

The Lower Charles River is a heavily utilized urban river that runs between Cambridge and Boston in Massachusetts. The recreational usage of the river is dependent on adequate water depths, but there have been no definitive prior studies on the sedimentation rate of the Lower Charles River. The river transitioned from tidal to a freshwater basin in 1908 due to the construction of the (old) Charles River Dam. Water surface height on the Lower Charles River is maintained within ±1 foot through controlled discharge at the new Charles River Dam. The current study area for historical comparisons is from the old Charles River Dam to the Boston University Bridge. This study conducted a bathymetric survey of the Lower Charles River, digitized three prior surveys in the study area, calculated volumes and depth distributions for each survey, and estimated sedimentation rates from fits to the volumes over time. The oldest chart digitized was produced in 1902 during dam construction deliberations. The average sedimentation rate is estimated as 5-10 mm/year, which implies 1.8-3.5 feet sedimentation since 1908. Sedimentation rates and distributions are necessary to develop comprehensive management plans for the river and there is evidence to suggest that sedimentation rates in the shallow upstream areas are higher than the inferred rates in the study area.

Sediment transport and deposition in the lower Missouri River during the 2011 flood

Science.gov (United States)

Alexander, Jason S.; Jacobson, Robert B.; Rus, David L.

2013-01-01

Hermann, Missouri. Measurements made in early January, when SSC was low, indicate that suspended sediment mostly was composed of bed material, but by mid-February, runoff from the plains caused PW to increase at most streamgages. Total suspended-sediment discharge (SSD) during water year 2011 at the selected streamgages in the lower Missouri River ranged from approximately 29 to 64 million tons. Total estimated SSD had the lowest exceedance frequencies in the reaches between Gavins Point Dam and Nebraska City, Nebraska, but exceedance frequencies increased substantially downstream. In 2011, total SSD with low exceedance frequencies were reported at Sioux City, Iowa, Omaha, Nebraska, and Nebraska City, Nebraska, despite moderate-to-high exceedance frequencies for annual average SSC, indicating that the duration of high-magnitude flooding was the primary driver of total SSD. Comparison of median SSC for samples from water year 2011 with samples in the 20 years prior indicated that median SSC for high-action streamflows (streamflows likely to produce a stage exceeding the National Weather Service’s “action stage”) in 2011 were lower than those typical for high-action streamflows. Multiple-comparison analysis indicated that median SSC values for low-action streamflows (streamflows likely to produce stages lower than the National Weather Service’s “action stage”) and high-action streamflows sampled in 2011 at 4 of 6 streamgages were not significantly distinguishable from median SSC values for low-action streamflows in the previous 20 years. Longitudinal comparison of streamflow and SSD exceedance frequencies for 2011 with corresponding frequencies for 2008 and 1993 indicated the important role of tributary contributions to total SSD in the lower Missouri River. In 1993 and 2008, tributaries were the primary source of floodwater in the lower Missouri River, which resulted in a 20-fold increase in total SSD from Sioux City, Iowa, to Hermann, Missouri. In 2011

Edaphic Conditions Regulate Denitrification Directly and Indirectly by Altering Denitrifier Abundance in Wetlands along the Han River, China.

Science.gov (United States)

Xiong, Ziqian; Guo, Laodong; Zhang, Quanfa; Liu, Guihua; Liu, Wenzhi

2017-05-16

Riparian wetlands play a critical role in retaining nitrogen (N) from upland runoff and improving river water quality, mainly through biological processes such as soil denitrification. However, the relative contribution of abiotic and biotic factors to riparian denitrification capacity remains elusive. Here we report the spatiotemporal dynamics of potential and unamended soil denitrification rates in 20 wetlands along the Han River, an important water source in central China. We also quantified the abundance of soil denitrifying microorganisms using nirK and nirS genes. Results showed that soil denitrification rates were significantly different between riparian and reservoir shoreline wetlands, but not between mountain and lowland wetlands. In addition, soil denitrification rates showed strong seasonality, with higher values in August (summer) and April (spring) but lower values in January (winter). The potential and unamended denitrification rates were positively correlated with edaphic conditions (moisture and carbon concentration), denitrifier abundance, and plant species richness. Path analysis further revealed that edaphic conditions could regulate denitrification rates both directly and indirectly through their effects on denitrifier abundance. Our findings highlight that not only environmental factors, but also biotic factors including denitrifying microorganisms and standing vegetation, play an important role in regulating denitrification rate and N removal capacity in riparian wetlands.

Architecture of channel-belt deposits in an aggrading shallow sandbed braided river: the lower Niobrara River, northeast Nebraska

Science.gov (United States)

Skelly, Raymond L.; Bristow, Charlie S.; Ethridge, Frank G.

2003-05-01

Architecture of recent channel-belt deposits of the Niobrara River, northeast Nebraska, USA, records the response of a sandy braided river to rapid base-level rise. Up to 3 m of aggradation has occurred within the lower 14 km of the Niobrara River since the mid-1950s as a result of base-level rise at the confluence of the Niobrara and Missouri Rivers. Aerial photographs and channel surveys indicate that the lower Niobrara has evolved from a relatively deep, stable channel with large, bank-attached braid bars to a relatively shallow, aggrading channel with braid bars and smaller secondary channels. Architecture of channel-belt deposits associated with the recent aggradation has been defined using ground-penetrating radar (GPR) and vibracores. The channel-belt deposits exhibit a series of amalgamated channel fills and braid bar complexes (i.e., macroforms). Radar facies identified in the GPR data represent architectural elements of the braid bar complexes, large and small bedforms [two-dimensional (2-D) and three-dimensional (3-D) dunes], and channels. Individual braid bars appear to consist of basal high-flow and upper low-flow components. Preservation of the complete, high-flow bar geometry is generally incomplete due to frequent migration of smaller scale, secondary channels within the channel belt (i.e., braided channel network) at low discharges. The large-scale stratification of the braid bar deposits is dominated by cross-channel and upstream accretion. Elements of downstream accretion are also recognized. These accretion geometries have not been documented previously in similar sandy braided rivers. Braid bar deposits with low-flow modification (e.g., incision by secondary channels) are recognized in the deeper portions of the deposits imaged by GPR. Preservation of braid bars, with both high- and low-flow components, is a result of the rapid base-level rise and channel-bed aggradation experienced by the Niobrara River over the past 45 years. Recent avulsion

Seismic scatterers in the mid-lower mantle beneath Tonga-Fiji

Science.gov (United States)

Kaneshima, Satoshi

2018-01-01

We analyze deep and intermediate-depth earthquakes at the Tonga-Fiji region in order to reveal the distribution of scattering objects in the mid-lower mantle. By array processing waveform data recorded at regional seismograph stations in the US, Alaska, and Japan, we investigate S-to-P scattering waves in the P coda, which arise from kilometer-scale chemically distinct objects in the mid-lower mantle beneath Tonga-Fiji. With ten scatterers previously reported by the author included, twenty-three mid-lower mantle scatterers have been detected below 900 km depth, while scatterers deeper than 1900 km have not been identified. Strong mid-lower mantle S-to-P scattering most frequently occurs at the scatterers located within a depth range between 1400 km and 1600 km. The number of scatterers decreases below 1600 km depth, and the deeper objects tend to be weaker. The scatterer distribution may reflect diminishing elastic anomalies of basaltic rocks with depth relative to the surrounding mantle rocks, which mineral physics has predicted to occur. The predominant occurrence of strong S-to-P scattering waves within a narrow depth range may reflect significant reduction of rigidity due to the ferro-elastic transformation of stishovite in basaltic rocks. Very large signals associated with mid-mantle scatterers are observed only for a small portion of the entire earthquake-array pairs. Such infrequent observations of large scattering signals, combined with quite large event-to-event differences in the scattering intensity for each scatterer, suggest both that the strong arrivals approximately represent ray theoretical S-to-P converted waves at objects with a plane geometry. The plane portions of the strong scatterers may often dip steeply, with the size exceeding 100 km. For a few strong scatterers, the range of receivers showing clear scattered waves varies substantially from earthquake-array pair to pair. Some of the scatterers are also observed at different arrays that have

Floodplain hydrodynamic modelling of the Lower Volta River in Ghana

Directory of Open Access Journals (Sweden)

Frederick Yaw Logah

2017-12-01

Full Text Available The impacts of dam releases from re-operation scenarios of the Akosombo and Kpong hydropower facilities on downstream communities along the Lower Volta River were examined through hydrodynamic modelling using the HEC-RAS hydraulic model. The model was used to simulate surface water elevation along the river reach for specified discharge hydrographs from proposed re-operation dam release scenarios. The morphology of the river and its flood plains together with cross-sectional profiles at selected river sections were mapped and used in the hydrodynamic modelling. In addition, both suspended and bed-load sediment were sampled and analysed to determine the current sediment load of the river and its potential to carry more sediment. The modelling results indicate that large areas downstream of the dam including its flood plains would be inundated if dam releases came close to or exceeded 2300 m3/s. It is therefore recommended to relocate communities along the banks and in the flood plains of the Lower Volta River when dam releases are to exceed 2300 m3/s. Suspended sediment transport was found to be very low in the Lower Volta River and the predominant soil type in the river banks and bed is sandy soil. Thus, the geomorphology of the river can be expected to change considerably with time, particularly for sustained high releases from the Akosombo and Kpong dams. The results obtained from this study form a basis for assessing future sedimentation problems in the Lower Volta River and for underpinning the development of sediment control and management strategies for river basins in Ghana. Keywords: Geomorphology, HEC-RAS model, Dam release, Floodplain, Lower Volta River, Ghana

Variations in zebra mussel (Dreissena polymorpha) veliger densities throughout 1996 at Dam 52 on the lower Ohio River

Science.gov (United States)

Reed, Darren P.; Herod, Jeffrey J.; Sickel, James B.

1998-01-01

Zebra mussel veliger densities were monitored throughout 1996 at Lock and Dam 52 on the lower Ohio River near Brookport, IL. The spawning season occurred between mid June and early September with veliger densities peaking at 30,000/m3 in late June. Veliger first appeared at a water temperature of 21° C. When spawning ended in September the water temperature was 22 °C. Veligers were found throughout November when the water temperature was 10 °C. The lowest temperature at which veligers were observed was 7 ° C in March 1996. These results show that the zebra mussels in the lower Ohio River are reproducing naturally and that spawning appears to be synchronous. The presence of larvae at low temperatures in March suggests that veligers are capable of delaying settlement and overwintering in the planktonic stage.

Sediment oxygen demand in the lower Willamette River, Oregon, 1994

Science.gov (United States)

Caldwell, James M.; Doyle, Micelis C.

1995-01-01

An investigation of sediment oxygen demand (SOD) at the interface of the stream and stream bed was performed in the lower Willamette River (river mile 51 to river mile 3) during August, 1994, as part of a cooperative project with the Oregon Department of Environmental Quality. The primary goals of the investigation were to measure the spatial variability of SOD in the lower Willamette River and to relate SOD to bottom-sediment characteristics.

Water Quality Projects Summary for the Mid-Columbia and Cumberland River Systems

Energy Technology Data Exchange (ETDEWEB)

Stewart, Kevin M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Witt, Adam M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hadjerioua, Boualem [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

2017-04-01

Scheduling and operational control of hydropower systems is accompanied with a keen awareness of the management of water use, environmental effects, and policy, especially within the context of strict water rights policy and generation maximization. This is a multi-objective problem for many hydropower systems, including the Cumberland and Mid-Columbia river systems. Though each of these two systems have distinct operational philosophies, hydrologic characteristics, and system dynamics, they both share a responsibility to effectively manage hydropower and the environment, which requires state-of-the art improvements in the approaches and applications for water quality modeling. The Department of Energy and Oak Ridge National Laboratory have developed tools for total dissolved gas (TDG) prediction on the Mid-Columbia River and a decision-support system used for hydropower generation and environmental optimization on the Cumberland River. In conjunction with IIHR - Hydroscience & Engineering, The University of Iowa and University of Colorado s Center for Advanced Decision Support for Water and Environmental Systems (CADSWES), ORNL has managed the development of a TDG predictive methodology at seven dams along the Mid-Columbia River and has enabled the ability to utilize this methodology for optimization of operations at these projects with the commercially available software package Riverware. ORNL has also managed the collaboration with Vanderbilt University and Lipscomb University to develop a state-of-the art method for reducing high-fidelity water quality modeling results into surrogate models which can be used effectively within the context of optimization efforts to maximize generation for a reservoir system based on environmental and policy constraints. The novel contribution of these efforts is the ability to predict water quality conditions with simplified methodologies at the same level of accuracy as more complex and resource intensive computing methods

Sources and compositional distribution of organic carbon in surface sediments from the lower Pearl River to the coastal South China Sea

Science.gov (United States)

Li, X.; Zhang, Z.; Wade, T.; Knap, A. H.; Zhang, C.

2017-12-01

The Pearl River plays an important role in transporting terrestrial organic carbon (OC) to the South China Sea (SCS). However, the sources and compositional distribution of OC in the system are poorly understood. This study focused on delineating the sources and determining the fate of surface sedimentary OC from the Feilaixia Hydro-power Station to the coastal SCS. Elemental, stable carbon/nitrogen isotope (δ13C, δ15N) and lignin-phenol analyses have been conducted. The total OC (TOC) from the up-stream sites were generally derived from vascular plants (higher C/N, and depleted δ13C) and soils. Additional input was attributed to riverine primary production (lower C/N and enriched δ13C), which was enhanced near the dam-created reservoir. The C/N and δ13C values were not significantly different among sites in the mid-stream. The estuary/coastal sites witnessed hydrodynamically sorted riverine OC, which was diluted by marine primary production (lower C/N and more enriched δ13C). The lignin concentration was the highest in the up-stream sites, remained relatively unchanged in the mid-stream sites and decreased significantly along the estuary/coastal sites, which was corroborated by variation in TOC. A comprehensive five-endmember Monte Carlo simulation suggested that previous studies had underestimated the C4 plant input by 14 ± 11% and overestimated the riverbank soil input by 21 ± 17%. Thus, our study provided valuable information for more accurate source and mass balance studies of terrestrial OC transported to the SCS, which helped to further understand the carbon cycling in the large river-ocean continuum.

Research, Monitoring, and Evaluation of Avian Predation on Salmonid Smolts in the Lower and Mid-Columbia River, 2006 Final Season Summary.

Energy Technology Data Exchange (ETDEWEB)

Roby, Daniel D. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University; Collis, Ken [Real Time Research, Inc.; Lyons, Donald E. [USGS - Oregon Cooperative Fish and Wildlife Research Unit, Oregon State University

2009-06-18

This study investigates predation by piscivorous waterbirds on juvenile salmonids (Oncorhynchus spp.) from throughout the Columbia River Basin. During 2006, study objectives in the Columbia River estuary, work funded by the Bonneville Power Administration, were to (1) monitor and evaluate previous management initiatives to reduce Caspian tern (Hydroprogne caspia) predation on juvenile salmonids (smolts); (2) measure the impact of double-crested cormorant (Phalacrocorax auritus) predation on smolt survival, and assess potential management options to reduce cormorant predation; and (3) monitor large colonies of other piscivorous waterbirds in the estuary (i.e., glaucous-winged/western gulls [Larus glaucescens/occidentalis]) to determine the potential impacts on smolt survival. Study objectives on the mid-Columbia River, work funded by the Walla Walla District of the U.S. Army Corps of Engineers, were to (1) measure the impact of predation by Caspian terns and double-crested cormorants on smolt survival; and (2) monitor large nesting colonies of other piscivorous waterbirds (i.e., California gulls [L. californicus], ring-billed gulls [L. delawarensis], American white pelicans [Pelecanus erythrorhynchos]) on the mid-Columbia River to determine the potential for significant impacts on smolt survival. Our efforts to evaluate system-wide losses of juvenile salmonids to avian predation indicated that Caspian terns and double-crested cormorants were responsible for the vast majority of smolt losses to avian predators in the Columbia Basin, with most losses occurring in the Columbia River estuary. In 2006, East Sand Island in the Columbia River estuary supported the largest known breeding colonies of Caspian terns and double-crested cormorants in the world. The Caspian tern colony on East Sand Island consisted of about 9,200 breeding pairs in 2006, up slightly (but not significantly so) from the estimate of colony size in 2005 (8,820 pairs). There has not been a

Development of river flood model in lower reach of urbanized river basin

Science.gov (United States)

Yoshimura, Kouhei; Tajima, Yoshimitsu; Sanuki, Hiroshi; Shibuo, Yoshihiro; Sato, Shinji; Lee, SungAe; Furumai, Hiroaki; Koike, Toshio

2014-05-01

Japan, with its natural mountainous landscape, has demographic feature that population is concentrated in lower reach of elevation close to the coast, and therefore flood damage with large socio-economic value tends to occur in low-lying region. Modeling of river flood in such low-lying urbanized river basin is complex due to the following reasons. In upstream it has been experienced urbanization, which changed land covers from natural forest or agricultural fields to residential or industrial area. Hence rate of infiltration and runoff are quite different from natural hydrological settings. In downstream, paved covers and construct of sewerage system in urbanized areas affect direct discharges and it enhances higher and faster flood peak arrival. Also tidal effect from river mouth strongly affects water levels in rivers, which must be taken into account. We develop an integrated river flood model in lower reach of urbanized areas to be able to address above described complex feature, by integrating model components: LSM coupled distributed hydrological model that models anthropogenic influence on river discharges to downstream; urban hydrological model that simulates run off response in urbanized areas; Saint Venant's equation approximated river model that integrates upstream and urban hydrological models with considering tidal effect from downstream. These features are integrated in a common modeling framework so that model interaction can be directly performed. The model is applied to the Tsurumi river basin, urbanized low-lying river basin in Yokohama and model results show that it can simulate water levels in rivers with acceptable model errors. Furthermore the model is able to install miscellaneous water planning constructs, such as runoff reduction pond in urbanized area, flood control field along the river channel, levee, etc. This can be a useful tool to investigate cost performance of hypothetical water management plan against impact of climate change in

Enhancing mud supply from the Lower Missouri River to the Mississippi River Delta USA: Dam bypassing and coastal restoration

Science.gov (United States)

Kemp, G. Paul; Day, John W.; Rogers, J. David; Giosan, Liviu; Peyronnin, Natalie

2016-12-01

Sand transport to the Mississippi River Delta (MRD) remains sufficient to build wetlands in shallow, sheltered coastal bays fed by engineered diversions on the Mississippi River (MR) and its Atchafalaya River (AR) distributary. But suspended mud (silt & clay) flux to the coast has dropped from a mean of 390 Mt y-1 in the early 1950s, to 100 Mt y-1 since 1970. This fine-grained sediment travels deeper into receiving estuarine basins and plays a critical role in sustaining existing marshes. Virtually all of the 300 Mt y-1 of missing mud once flowed from the Missouri River (MOR) Basin before nearly 100 dams were built as part of the Pick-Sloan water development project. About 100 Mt y-1 is now intercepted by main-stem Upper MOR dams closed in 1953. But the remaining 200 Mt y-1 is trapped by impoundments built on tributaries to the Lower MOR in the 1950s and 1960s. Sediment flux during the post-dam high MOR discharge years of 1973, 1993 and 2011 approached pre-dam levels when tributaries to the Lower MOR, including the Platte and Kansas Rivers, contributed to flood flows. West bank tributaries drain a vast, arid part of the Great Plains, while those entering from the east bank traverse the lowlands of the MOR floodplain. Both provinces are dominated by highly erodible loess soils. Staunching the continued decline in MR fine-grained sediment flux has assumed greater importance now that engineered diversions are being built to reconnect the Lowermost MR to the MRD. Tributary dam bypassing in the Lower MOR basin could increase mud supply to the MRD by 100-200 Mt y-1 within 1-2 decades. Such emergency measures to save the MRD are compatible with objectives of the Missouri River Restoration and Platte River Recovery Programs to restore MOR riparian habitat for endangered species. Rapid mobilization to shunt fine-grained sediments past as many as 50 Lower MOR tributary dams in several U.S. states will undoubtedly require as much regional coordination and funding in the 21st

The Hans Tausen drill

DEFF Research Database (Denmark)

Johnsen, Sigfus Johann; Dahl-Jensen, Dorthe; Steffensen, Jørgen Peder

2007-01-01

In the mid-1990s, excellent results from the GRIP and GISP2 deep drilling projects in Greenland opened up funding for continued ice-coring efforts in Antarctica (EPICA) and Greenland (NorthGRIP). The Glaciology Group of the Niels Bohr Institute, University of Copenhagen, was assigned the task...... of providing drilling capability for these projects, as it had done for the GRIP project. The group decided to further simplify existing deep drill designs for better reliability and ease of handling. The drill design decided upon was successfully tested on Hans Tausen Ice Cap, Peary Land, Greenland, in 1995....... The 5.0 m long Hans Tausen (HT) drill was a prototype for the ~11 m long EPICA and NorthGRIP versions of the drill which were mechanically identical to the HT drill except for a much longer core barrel and chips chamber. These drills could deliver up to 4 m long ice cores after some design improvements...

Heavy Metal Pollution of Lakes along the Mid-Lower Reaches of the Yangtze River in China: Intensity, Sources and Spatial Patterns

Science.gov (United States)

Zeng, Haiao; Wu, Jinglu

2013-01-01

Lakes in the middle and lower reaches of the Yangtze River form a shallow lake group unique in the World that is becoming increasingly polluted by heavy metals. Previous studies have largely focused on individual lakes, with limited exploration of the regional pattern of heavy metal pollution of the lake group in this area. This paper explores the sources, intensity and spatial patterns of heavy metal pollution of lake sediments. A total of 45 sample lakes were selected and the concentrations of key metal elements in the sediments of each lake were measured. The cluster analysis (CA), principal component analysis (PCA) and Geo-accumulation index (Ig) analysis permitted analysis of the source and pollution intensity of the target lakes. Results suggested a notable spatial variation amongst the sample lakes. Lakes in the upper part of the lower reach of the Yangtze River surrounded by typical urban landscapes were strongly or extremely polluted, with high concentrations of Pb, Zn, Cu and Cd in their sediments. This was attributed to large amount of untreated industrial discharges and municipal sewage produced within the lake catchments. In contrast, the heavy-metal pollution of lakes in the Taihu Delta area was notably lower due to industrial restructuring and implementation of effective environmental protection measures. Lakes along the middle reach of Yangtze River surrounded by agricultural areas were unpolluted to moderately polluted by heavy metals overall. Our results suggested that lakes in the central part of China require immediate attention and efforts should be made to implement management plans to prevent further degradation of water quality in these lakes. PMID:23442559

Channel and island change in the lower Platte River, Eastern Nebraska, USA: 1855 2005

Science.gov (United States)

Joeckel, R. M.; Henebry, G. M.

2008-12-01

The lower Platte River has undergone considerable change in channel and bar characteristics since the mid-1850s in four 20-25 km-long study stretches. The same net effect of historical channel shrinkage that was detected upstream from Grand Island, Nebraska, can also be detected in the lower river but differences in the behaviors of study stretches upstream and downstream from major tributaries are striking. The least relative decrease occurred downstream from the Loup River confluence, and the stretch downstream from the Elkhorn River confluence actually showed an increase in channel area during the 1940s. Bank erosion was also greater downstream of the tributaries between ca. 1860 and 1938/1941, particularly in stretch RG, which showed more lateral migration. The cumulative island area and the ratio of island area to channel area relative to the 1938/1941 baseline data showed comparatively great fluctuations in median island size in both downstream stretches. The erratic behavior of island size distributions over time indicates that large islands were accreted to the banks at different times, and that some small, newly-stabilized islands were episodically "flushed" out of the system. In the upstream stretches the stabilization of mobile bars to create new, small islands had a more consistent impact over time. Channel decrease by the abandonment of large, long-lived anabranches and by the in-place narrowing resulting from island accretion were more prominent in these upstream stretches. Across all of the study area, channel area appears to be stabilizing gradually as the rate of decrease lessens. This trend began earliest in stretch RG in the late 1950s and was accompanied by shifts in the size distributions of stabilized islands in that stretch into the 1960s. Elsewhere, even in the easternmost study stretch, stabilizing was occurring by the late 1960s, the same time frame documented by investigations of the Platte system upstream of the study area. Comprehensive

Monitoring of protected areas of the Lower Vistula River

OpenAIRE

Dawid Aleksander Szatten; Zbigniew Czerebiej

2018-01-01

The main aim of the research was to determine the quantitative and qualitative assessment of the condition of surface waters in the protected areas of the Lower Vistula River. The research included the analysis of the surface water monitoring network in the Lower Vistula catchment area in the water management cycle 2010-2015. The research subject was Lower Vistula on the section from the Wloclawek Reservoir (km 675) to the estuary of the river to the Gdańsk Bay (km 941). The most important re...

Comparison of land–atmosphere interaction at different surface types in the mid- to lower reaches of the Yangtze River valley

Directory of Open Access Journals (Sweden)

W. Guo

2016-08-01

Full Text Available The mid- to lower reaches of the Yangtze River valley are located within the typical East Asian monsoon zone. Rapid urbanization, industrialization, and development of agriculture have led to fast and complicated land use and land cover change in this region. To investigate land–atmosphere interaction in this region where human activities and monsoon climate have considerable interaction with each other, micrometeorological elements over four sites with different surface types around Nanjing, including urban surface at Dangxiao (hereafter DX-urban, suburban surface at Xianling (XL-suburb, and grassland and farmland at Lishui County (LS-grass and LS-crop, are analyzed and their differences are revealed. The impacts of surface parameters of different surface types on the radiation budget and land surface–atmosphere heat, water, and mass exchanges are investigated and compared. The results indicate the following. (1 The largest differences in daily average surface air temperature (Ta, surface skin temperature (Ts, and relative humidity (RH, which are found during the dry periods between DX-urban and LS-crop, can be up to 3.21 °C, 7.26 °C, and 22.79 %, respectively. The diurnal ranges of the above three elements are the smallest at DX-urban and the largest at LS-grass, XL-suburb, and LS-crop. (2 Differences in radiative fluxes are mainly reflected in upward shortwave radiation (USR that is related to surface albedo and upward longwave radiation (ULR that is related to Ts. When comparing four sites, it can be found that both the smallest USR and the largest ULR occur at the DX-urban site. The diurnal variation in ULR is same as that of Ts at all four sites. (3 The differences in daily average sensible heat (H and latent heat (LE between DX-urban and LS-crop are larger than 45 and 95 Wm−2, respectively. The proportion of latent heat flux in the net radiation (LE/Rn keeps increasing with the change in season from the spring to summer

Hydraulic Characteristics of the Lower Snake River during Periods of Juvenile Fall Chinook Salmon Migration, 2002-2006 Final Report.

Energy Technology Data Exchange (ETDEWEB)

Cook, C.; Dibrani, B.; Richmond, M.; Bleich, M.; Titzler, P..; Fu, T. [Pacific Northwest National Laboratory

2006-01-01

This report documents a four-year study to assess hydraulic conditions in the lower Snake River. The work was conducted for the Bonneville Power Administration, U.S. Department of Energy, by the Pacific Northwest National Laboratory. Cold water released from the Dworshak Reservoir hypolimnion during mid- to late-summer months cools the Clearwater River far below equilibrium temperature. The volume of released cold water augments the Clearwater River, and the combined total discharge is on the order of the Snake River discharge when the two rivers meet at their confluence near the upstream edge of Lower Granite Reservoir. With typical temperature differences between the Clearwater and Snake rivers of 10 C or more during July and August, the density difference between the two rivers during summer flow augmentation periods is sufficient to stratify Lower Granite Reservoir as well as the other three reservoirs downstream. Because cooling of the river is desirable for migrating juvenile fall Chinook salmon (Oncorhynchus tshawytscha) during this same time period, the amount of mixing and cold water entrained into Lower Granite Reservoir's epilimnion at the Clearwater/Snake River confluence is of key biological importance. Data collected during this project indicates the three reservoirs downstream of Lower Granite also stratify as direct result of flow augmentation from Dworshak Reservoir. These four reservoirs are also heavily influenced by wind forcing at the water's surface and during periods of low river discharge often behave like a two-layer lake. During these periods of stratification, lower river discharge, and wind forcing, the water in the upper layer of the reservoir is held in place or moves slightly upstream. This upper layer is also exposed to surface heating and may warm up to temperatures close to equilibrium temperature. The thickness (depth) of this upper warm layer and its direction of travel may be of key biological importance to juvenile

Sediment transport and capacity change in three reservoirs, Lower Susquehanna River Basin, Pennsylvania and Maryland, 1900-2012

Science.gov (United States)

Langland, Michael J.

2015-01-01

The U.S. Geological Survey (USGS) has conducted numerous sediment transport studies in the Susquehanna River and in particular in three reservoirs in the Lower Susquehanna River Basin to determine sediment transport rates over the past century and to document changes in storage capacity. The Susquehanna River is the largest tributary to Chesapeake Bay and transports about one-half of the total freshwater input and substantial amounts of sediment and nutrients to the bay. The transported loads are affected by deposition in reservoirs (Lake Clarke, Lake Aldred, and Conowingo Reservoir) behind three hydropower dams. The geometry and texture of the deposited sediments in each reservoir upstream from the three dams has been a subject of research in recent decades. Particle size deposition and sediment scouring processes are part of the reservoir dynamics. A Total Maximum Daily Load (TMDL) for nitrogen, phosphorus, and sediment was established for Chesapeake Bay to attain water-quality standards. Six states and the District of Columbia agreed to reduce loads to the bay and to meet load allocation goals for the TMDL. The USGS has been estimating annual sediment loads at the Susquehanna River at Marietta, Pennsylvania (above Lake Clarke), and Susquehanna River at Conowingo, Maryland (below Conowingo Reservoir), since the mid-1980s to predict the mass balance of sediment transport through the reservoir system. Using streamflow and sediment data from the Susquehanna River at Harrisburg, Pennsylvania (upstream from the reservoirs), from 1900 to 1981, sediment loads were greatest in the early to mid-1900s when land disturbance activities from coal production and agriculture were at their peak. Sediment loads declined in the 1950s with the introduction of agricultural soil conservation practices. Loads were dominated by climatic factors in the 1960s (drought) and 1970s (very wet) and have been declining since the 1980s through 2012. The USGS developed a regression equation to

Historical Channel Adjustment and Estimates of Selected Hydraulic Values in the Lower Sabine River and Lower Brazos River Basins, Texas and Louisiana

Science.gov (United States)

Heitmuller, Franklin T.; Greene, Lauren E.

2009-01-01

The U.S. Geological Survey, in cooperation with the Texas Water Development Board, evaluated historical channel adjustment and estimated selected hydraulic values at U.S. Geological Survey streamflow-gaging stations in the lower Sabine River Basin in Texas and Louisiana and lower Brazos River Basin in Texas to support geomorphic assessments of the Texas Instream Flow Program. Channel attributes including cross-section geometry, slope, and planform change were evaluated to learn how each river's morphology changed over the years in response to natural and anthropogenic disturbances. Historical and contemporary cross-sectional channel geometries at several gaging stations on each river were compared, planform changes were assessed, and hydraulic values were estimated including mean flow velocity, bed shear stress, Froude numbers, and hydraulic depth. The primary sources of historical channel morphology information were U.S. Geological Survey hard-copy discharge-measurement field notes. Additional analyses were done using computations of selected flow hydraulics, comparisons of historical and contemporary aerial photographs, comparisons of historical and contemporary ground photographs, evaluations of how frequently stage-discharge rating curves were updated, reviews of stage-discharge relations for field measurements, and considerations of bridge and reservoir construction activities. Based on historical cross sections at three gaging stations downstream from Toledo Bend Reservoir, the lower Sabine River is relatively stable, but is subject to substantial temporary scour-and-fill processes during floods. Exceptions to this characterization of relative stability include an episode of channel aggradation at the Sabine River near Bon Wier, Texas, during the 1930s, and about 2 to 3 feet of channel incision at the Sabine River near Burkeville, Texas, since the late 1950s. The Brazos River, at gaging stations downstream from Waco, Texas, has adjusted to a combination of

Morphodynamic change analysis of bedforms in the Lower Orinoco River, Venezuela

Science.gov (United States)

Yepez, Santiago Paul; Laraque, Alain; Gualtieri, Carlo; Christophoul, Frédéric; Marchan, Claudio; Castellanos, Bartolo; Azocar, Jose Manuel; Lopez, Jose Luis; Alfonso, Juan

2018-04-01

The Orinoco River has the third largest discharge in the world, with an annual mean flow of 37 600 m3 s-1 at its outlet to the Atlantic Ocean. Due to the presence of the Guiana Shield on the right bank, the lower reach of the Orinoco has a plan form characterized by contraction and expansion zones. Typical 1-1.5 km wide narrow reaches are followed by 7-8 km wide reaches. A complex pattern of bed aggradation and degradation processes takes place during the annual hydrological regime. A series of Acoustic Doppler Current Profiler (ADCP) transects were collected on an expansion channel in the Orinoco River, specifically over a fluvial island, representative of the lower Orinoco. In this study, temporal series of bathymetric cartography obtained by ADCP profiles combined with Differential Global Position System (DGPS) measurements (with dual-frequency), were used to recover the local displacement of bed forms in this island. The principal aims of this analysis were: (1) to understand the dynamics and evolution of sand waves and bars at this section and (2) to quantify the volume (erosion vs. accretion) of a mid-channel bar with dunes by applying DEM of Difference (DoD) maps on time series of bathymetric data. This required sampling with ADCP transects during the months of: May 2016; November 2016 and April 2017. Each bathymetric transect was measured twice, 1 day apart and on the same trajectory obtained by a GPS receptor. The spatial analysis of these ADCP transects is presented as a novel tool in the acquisition of time series of bathymetry for a relatively deep section ( ˜ 20 m) and under variable flow conditions.

A velocimetric survey of the Lower Missouri River from river mile 492.38 to 290.20, July-October 2011 and July 2012

Science.gov (United States)

Armstrong, Daniel J.; Wilkison, Donald H.; Norman, Richard D.

2014-01-01

Velocimetric surveys were made by the U.S. Geological Survey in 2011 and 2012 to provide data for the U.S. Army Corps of Engineers’ ongoing study of bed degradation in the Lower Missouri River. Using Acoustic Doppler Current Profile technology, velocity data were collected at 87 river miles along the Lower Missouri River from Rulo, Nebraska to Waverly, Missouri, from July to October 2011 and in July 2012, for a total of 118 velocimetric surveys. Multiple-repeat velocimetric surveys were done eight times at three river miles from July to October 2011. Synoptic velocimetric surveys spanning 2–4 days were done twice at ten river miles, once in July 2011 and once in October 2011. Additional synoptic velocimetric surveys were done at proximal river miles in October 2011 and July 2012. Main-channel, near-bed, near-bank, and whole-river velocities were extracted from the Acoustic Doppler Current Profile data using AdMap and compiled as an average of reciprocal pairs for each survey. In addition, the mean velocity computed by the Winriver II software for each survey was integrated with the extracted data.

A floodplain continuum for Atlantic coast rivers of the Southeastern US: Predictable changes in floodplain biota along a river's length

Science.gov (United States)

Batzer, Darold P.; Noe, Gregory; Lee, Linda; Galatowitsch, Mark

2018-01-01

Floodplains are among the world’s economically-most-valuable, environmentally-most-threatened, and yet conceptually-least-understood ecosystems. Drawing on concepts from existing riverine and wetland models, and empirical data from floodplains of Atlantic Coast rivers in the Southeastern US (and elsewhere when possible), we introduce a conceptual model to explain a continuum of longitudinal variation in floodplain ecosystem functions with a particular focus on biotic change. Our hypothesis maintains that major controls on floodplain ecology are either external (ecotonal interactions with uplands or stream/river channels) or internal (wetland-specific functions), and the relative importance of these controls changes progressively from headwater to mid-river to lower-river floodplains. Inputs of water, sediments, nutrients, flora, and fauna from uplands-to-floodplains decrease, while the impacts of wetland biogeochemistry and obligate wetland plants and animals within-floodplains increase, along the length of a river floodplain. Inputs of water, sediment, nutrients, and fauna from river/stream channels to floodplains are greatest mid-river, and lower either up- or down-stream. While the floodplain continuum we develop is regional in scope, we review how aspects may apply more broadly. Management of coupled floodplain-river ecosystems would be improved by accounting for how factors controlling the floodplain ecosystem progressively change along longitudinal riverine gradients.

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix D: Natural River Drawdown Engineering

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Geomorphology and river dynamics of the lower Copper River, Alaska

Science.gov (United States)

Brabets, Timothy P.; Conaway, Jeffrey S.

2009-01-01

effects that betterments, such as guide banks or bridge extensions, would have on flow conditions and to provide sound conceptual information that could help decide if a proposed betterment will work or determine potential problems that need to be addressed for a particular betterment. The ability of the model to simulate these hydraulic conditions was constrained by the accuracy and level of channel geometry detail, which is constantly changing in the lower Copper River.

Morphodynamic change analysis of bedforms in the Lower Orinoco River, Venezuela

Directory of Open Access Journals (Sweden)

S. P. Yepez

2018-04-01

Full Text Available The Orinoco River has the third largest discharge in the world, with an annual mean flow of 37 600 m3 s−1 at its outlet to the Atlantic Ocean. Due to the presence of the Guiana Shield on the right bank, the lower reach of the Orinoco has a plan form characterized by contraction and expansion zones. Typical 1–1.5 km wide narrow reaches are followed by 7–8 km wide reaches. A complex pattern of bed aggradation and degradation processes takes place during the annual hydrological regime. A series of Acoustic Doppler Current Profiler (ADCP transects were collected on an expansion channel in the Orinoco River, specifically over a fluvial island, representative of the lower Orinoco. In this study, temporal series of bathymetric cartography obtained by ADCP profiles combined with Differential Global Position System (DGPS measurements (with dual-frequency, were used to recover the local displacement of bed forms in this island. The principal aims of this analysis were: (1 to understand the dynamics and evolution of sand waves and bars at this section and (2 to quantify the volume (erosion vs. accretion of a mid-channel bar with dunes by applying DEM of Difference (DoD maps on time series of bathymetric data. This required sampling with ADCP transects during the months of: May 2016; November 2016 and April 2017. Each bathymetric transect was measured twice, 1 day apart and on the same trajectory obtained by a GPS receptor. The spatial analysis of these ADCP transects is presented as a novel tool in the acquisition of time series of bathymetry for a relatively deep section ( ∼ 20 m and under variable flow conditions.

Assessment of denitrification process in lower Ishikari river system, Japan.

Science.gov (United States)

Jha, Pawan Kumar; Minagawa, Masao

2013-11-01

Sediment denitrification rate and its role in removal of dissolved nitrate load in lower Ishikari river system were examined. Denitrification rate were measured using acetylene inhibition technique on the sediment samples collected during August 2009-July 2010. The denitrification rate varied from 0.001 to 1.9 μg Ng(-1) DM h(-1) with an average value of 0.21 μg Ng(-1) DM h(-1) in lower Ishikari river system. Denitrification rate showed positive correlation with dissolved nitrate concentration in the river basin, indicating overlying water column supplied nitrate for the sediment denitrification processes. Nutrient enrichment experiments result showed that denitrification rate increased significantly with addition of nitrate in case of samples collected from Barato Lake however no such increase was observed in the samples collected from Ishikari river main channel and its major tributaries indicating that factors other than substrate concentration such as population of denitrifier and hydrological properties of stream channel including channel depth and flow velocity may affects the denitrification rate in lower Ishikari river system. Denitrification rate showed no significant increase with the addition of labile carbon (glucose), indicating that sediment samples had sufficient organic matter to sustain denitrification activity. The result of nutrient spiraling model indicates that in- stream denitrification process removes on an average 5%d(-1) of dissolve nitrate load in Ishikari river. This study was carried out to fill the gap present in the availability of riverine denitrification rate measurement and its role in nitrogen budget from Japanese rivers characterize by small river length and high flow rate. Copyright © 2013 Elsevier Ltd. All rights reserved.

What was the transport mode of large boulders in the Campine Plateau and the lower Meuse valley during the mid-Pleistocene?

Science.gov (United States)

De Brue, Hanne; Poesen, Jean; Notebaert, Bastiaan

2015-01-01

The Campine Plateau in northeastern Belgium, a remnant of an alluvial fan deposited by the Meuse River during the mid-Pleistocene, is characterised by the presence of boulders with maximum dimensions of up to 2 m, embedded in a gravel matrix. These boulders originated in the Ardennes region and are generally assumed to have been transported by ice-rafting processes. This paper investigates for the first time quantitatively the possibility of purely hydraulic transport of the boulders, taking into account channel and flow characteristics in the boulder provenance area during the mid-Pleistocene. Empirical transport relations that describe incipient motion thresholds in nonuniform river beds as a function of the relative grain size, or the ratio between the grain size of interest and the median grain size of the channel bed, are applied in order to calculate critical water depths for transport of boulders of various sizes. Results indicate that hydraulic transport of boulders with intermediate diameters < 1 m could have occurred within limited reaches of the palaeoriver, more specifically in the palaeo-Amblève tributary; whereas the small slope gradient of the palaeo-Meuse most probably inhibited boulder movement by hydraulic forces only. Although calculations of the ice volume required to lift a boulder to the water surface and comparison of the ice floe's dimensions with palaeochannel morphology do suggest that ice rafting is theoretically possible, several alternative, more probable transport mechanisms for the larger boulders of the Campine Plateau are proposed, requiring much smaller critical ice volumes and water depths than ice-rafting processes or purely hydraulic transport. These hypotheses include decreased bed friction and effective boulder density caused by a limited ice layer attached to the river bed and the boulder, hence lowering hydraulic transport thresholds, as well as the formation of ice jams and dams inducing catastrophic flooding and

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix L: Lower Snake River Mitigation History and Status. Appendix M: Fish and Wildlife Coordination Act Report

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Multi-residues analysis of pre-emergence herbicides in fluvial sediments: application to the mid-Garonne River.

Science.gov (United States)

Devault, Damien A; Merlina, Georges; Lim, Puy; Probst, Jean-Luc; Pinelli, Eric

2007-09-01

Contamination of man and ecosystems by pesticides has become a major environmental concern. Whereas many studies exist on contamination from agriculture, the effects of urban sources are usually omitted. Fluvial sediment is a complex matrix of pollutants but little is known of its recent herbicide content. This study proposes a method for a fast and reliable analysis of herbicides by employing the accelerated solvent extractor (ASE). The aim of the study is to show the impact of a major town (Toulouse) on the herbicide content in the river. In this study, three herbicide families (i.e.s-triazine, substituted ureas and anilides) were analysed in fluvial sediment fractions at 11 sampling sites along the mid-Garonne River and its tributaries. River water contamination by herbicides is minor, except for at three sites located in urban areas. Among the herbicidal families studied, urban and suburban areas are distinguished from rural areas and were found to be the most contaminated sites during the study period, a winter low-water event. The herbicide content of the coarse sediment fractions is about one third of that found in the fine fractions and usually ignored. The distribution of pesticide concentrations across the whole range of particle sizes was investigated to clarify the role of plant remains on the significant accumulation in the coarse fractions.

Effect of human activities on overall trend of sedimentation in the lower Yellow River, China.

Science.gov (United States)

Jiongxin, Xu

2004-05-01

The Yellow River has been intensively affected by human activities, particularly in the past 50 years, including soil-water conservation in the upper and middle drainage basin, flood protection in the lower reaches, and flow regulation and water diversion in the whole drainage basin. All these changes may impact sedimentation process of the lower Yellow River in different ways. Assessing these impacts comprehensively is important for more effective environmental management of the drainage basin. Based on the data of annual river flow, sediment load, and channel sedimentation in the lower Yellow River between 1950 and 1997, the purpose of this paper is to analyze the overall trend of channel sedimentation rate at a time scale of 50 years, and its formative cause. It was found in this study that erosion control measures and water diversion have counteractive impacts on sedimentation rate in the lower Yellow River. Although both annual river flow and sediment decreased, there was no change in channel sedimentation rate. A regression analysis indicated that the sedimentation in the lower Yellow River decreased with the sediment input to the lower Yellow River but increased with the river flow input. In the past 30-40 years, the basin-wide practice of erosion and sediment control measures resulted in a decline in sediment supply to the Yellow River; at the same time, the human development of water resources that required river flow regulation and water diversion caused great reduction in river flow. The former may reduce the sedimentation in the lower Yellow River, but the reduction of river flow increased the sedimentation. When their effects counterbalanced each other, the overall trend of channel sedimentation in the lower Yellow River remained unchanged. This fact may help us to better understand the positive and negative effects of human activities in the Yellow River basin and to pay more attention to the negative effect of the development of water resources. The

Meeting instream flow needs of lower Colorado River in Texas

International Nuclear Information System (INIS)

Martin, Q.W.

1993-01-01

The Lower Colorado River Authority (LCRA), an agency of the State of Texas, manages the surface waters of the lower Colorado River in Texas. The major water supply source in the lower basin is the Highland Lakes chain of reservoirs in Central Texas. The use of water from these lakes for environmental protection and enhancement has received increasing attention in recent years. The LCRA recently completed major revisions to its comprehensive Water Management Plan (WMP) for the Highland Lakes. These revisions included changes to incorporate the results of a three year study of instream flow needs in the lower Colorado River. The instream flow needs were determined to consist of two flow regimes: critical and target. The critical flows are considered to be the daily minimum flows needed to maintain minimum viable aquatic conditions for important fish species. The target flow needs are those daily flows which maximize the available habitat for a variety of fish. After evaluating numerous policy options, LCRA revised to WMP to allow the release of water from the Highland Lakes to maintain the daily river flows at no less than the critical flows in all years. Further, in those years when drought-induced irrigation water supply curtailments do not occur, LCRA will release water from the lakes, to the extent of daily inflows, to maintain daily river flows at no less than the target levels. To fully honor this pledge, LCRA committed an average of 28,700 acre-feet annually, during any ten consecutive years, from the dependable supply of the Highland Lakes

Age, growth and mortality of Clarias gariepinus (Siluriformes: Clariidae in the Mid-Cross River-Floodplain ecosystem, Nigeria

Directory of Open Access Journals (Sweden)

Okechukwu Idumah Okogwu

2011-12-01

Full Text Available Clarias gariepinus is a threatened highly prized species used for some elite ceremonies by the local communities. Artisanal fishers take advantage of this species annual breeding migration from the lower Cross River to the floodplain lakes in Mid-Cross River during the rainy season, and some migrant stocks are not able to spawn. Since there is a lack of information on this species population dynamics in the Mid-Cross area, this study aimed to evaluate the age, growth and mortality to support the development of effective management plans. For this, monthly overnight gill net catches (from 6 to 72mm mesh sizes were developed between March 2005 and February 2007. Growth parameters were determined using the FiSAT II length-frequency distribution. A total of 1 421 fish were collected during the survey. The asymptotic growth (L∞ was 80.24cm, growth rate (K was 0.49/year while the longevity was 6.12years. The annual instantaneous rate of total mortality (Z was 2.54/year and the natural mortality (M was 0.88. Fishing mortality (1.66/year was higher than the biological reference points (Fopt=0.83 and Flimit=1.11 and the exploitation rate (0.66 was higher than the predicted value (Emax=0.64 indicating that C. gariepinus was over exploited in the Mid-Cross River-Floodplain ecosystem. Some recommended immediate management actions are to strengthen the ban of ichthyocide fishing, closure of the floodplain lakes for most of the year, restricted access to the migratory path of the fish during the flood period and vocational training to the fishers. In order to recover and maintain a sustainable harvest, I suggest that a multi-sector stakeholder group should be formed with governmental agents, community leaders, fishers, fisheries scientists and non-governmental organizations. These short and long term measures, if carefully applied, will facilitate recovery of the fishery. Rev. Biol. Trop. 59 (4: 1707-1716. Epub 2011 December 01.Clarias gariepinus es una

Quality of surface waters in the lower Columbia River Basin

Science.gov (United States)

Santos, John F.

1965-01-01

This report, made during 1959-60, provides reconnaissance data on the quality of waters in the lower Columbia River basin ; information on present and future water problems in the basin; and data that can be employed both in water-use studies and in planning future industrial, municipal, and agricultural expansion within this area. The lower Columbia River basin consists of approximately 46,000 square miles downstream from the confluence of the Snake and Columbia Rivers The region can be divided into three geographic areas. The first is the heavily forested, sparsely populated mountain regions in which quality of water in general is related to geologic and climatological factors. The second is a semiarid plateau east of the Cascade Mountains; there differences in geology and precipitation, together with more intensive use of available water for irrigation, bring about marked differences in water quality. The third is the Willamette-Puget trough area in which are concentrated most of the industry and population and in which water quality is influenced by sewage and industrial waste disposal. The majority of the streams in the lower Columbia River basin are calcium magnesium bicarbonate waters. In general, the rivers rising in the. Coast Range and on the west slope of the Cascade Range contain less than 100 parts per million of dissolved solids, and hardness of the water is less than 50 parts per million. Headwater reaches of the streams on the east slope of the Cascade Range are similar to those on the west slope; but, downstream, irrigation return flows cause the dissolved-solids content and hardness to increase. Most of the waters, however, remain calcium magnesium bicarbonate in type. The highest observed dissolved-solids concentrations and also some changes in chemical composition occur in the streams draining the more arid parts of the area. In these parts, irrigation is chiefly responsible for increasing the dissolved-solids concentration and altering the

Phenomena and characteristics of barrier river reaches in the middle and lower Yangtze River, China

Science.gov (United States)

You, Xingying; Tang, Jinwu

2017-06-01

Alluvial river self-adjustment describes the mechanism whereby a river that was originally in an equilibrium state of sediment transport encounters some disturbance that destroys the balance and results in responses such as riverbed deformation. A systematic study of historical and recent aerial photographs and topographic maps in the Middle and Lower Reaches of the Yangtze River (MLYR) shows that river self-adjustment has the distinguishing feature of transferring from upstream to downstream, which may affect flood safety, waterway morphology, bank stability, and aquatic environmental safety over relatively long reaches downstream. As a result, it is necessary to take measures to control or block this transfer. Using the relationship of the occurrence time of channel adjustments between the upstream and downstream, 34 single-thread river reaches in the MLYR were classified into four types: corresponding, basically corresponding, basically not corresponding, not corresponding. The latter two types, because of their ability to prevent upstream channel adjustment from transferring downstream, are called barrier river reaches in this study. Statistics indicate that barrier river reaches are generally single thread and slightly curved, with a narrow and deep cross-sectional morphology, and without flow deflecting nodes in the upper and middle parts of reaches. Moreover, in the MLYR, barrier river reaches have a hydrogeometric coefficient of {}1.2‱, a silty clay content of the concave bank {>}{9.5}%, and a median diameter of the bed sediment {>}{0.158} mm. The barrier river reach mechanism lies in that can effectively centralise the planimetric position of the main stream from different upstream directions, meaning that no matter how the upper channel adjusts, the main stream shows little change, providing relatively stable inflow conditions for the lower reaches. Regarding river regulation, it is necessary to optimise the benefits of barrier river reaches; long river

First survey of parasitic helminths of goats along the Han River in Hubei Province, China.

Science.gov (United States)

Yang, Xin; Gasser, Robin B; Fang, Rui; Zeng, Jinrong; Zhu, Kaixiang; Qi, Mingwei; Zhang, Zongze; Tan, Li; Lei, Weiqiang; Zhou, Yanqin; Zhao, Junlong; Hu, Min

2016-09-01

Diseases caused by parasitic helminths cause considerable production and economic losses in livestock worldwide. Understanding the epidemiology of these parasites has important implications for controlling them. The main purpose of the present study was to estimate the prevalence of key parasitic helminths in goats along the Han River in Zhanggang, Hubei Province (from January to December 2014). We used faecal flotation and sedimentation techniques as well as PCR-based DNA sequencing to detect and identify helminths. Results showed that the prevalence of helminths was high throughout the year, particularly for gastrointestinal nematodes. These first findings provide useful baseline information for goat helminths in Zhanggang, and a starting point for the implementation of control programs. With an increased expansion of the goat industry in China, the findings also emphasise the need to undertake prevalence surveys in other regions of China where extensive farming practices are used.

Evaluate Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2001-2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Faler, Michael P. (US Fish and Wildlife Service, Idaho Fishery Resource Office, Ahsahka, ID); Mendel, Glen W.; Fulton, Carl (Washington Department of Fish and Wildlife, Fish Management Division, Dayton, WA)

2003-06-01

We collected, radio-tagged, and PIT-tagged 41 bull trout at the Tucannon River Hatchery trap from May 17, through June 14, 2002. An additional 65 bull trout were also collected and PIT tagged by June 24, at which time we ceased PIT tagging operations because water temperatures were reaching 16.0 C or higher on a regular basis. Six radio-tags were recovered shortly after tagging, and as a result, 35 remained in the river through November 30, 2002. During the month of July, radio-tagged bull trout exhibited a general upstream movement into the upper reaches of the Tucannon Subbasin. We began to observe some downstream movements of radio-tagged bull trout in mid to late September and throughout October. These movements appeared to be associated with post spawning migrations. As of November 30, radio tagged bull trout were relatively stationary, and distributed from the headwaters downstream to river mile 11.3, near Pataha Creek. None of the radio-tagged bull trout left the Tucannon Subbasin and entered the federal hydropower system on the mainstem Snake River. We conducted some initial transmission tests of submerged radio tags at depths of 25, 35, 45, and 55 ft. in Lower Monumental Pool to test our capability of detection at these depths. Equipment used included Lotek model MCFT-3A transmitters, an SRX 400 receiver, a 4 element Yagi antenna, and a Lotek ''H'' antenna. Test results indicated that depth transmission of these tags was poor; only the transmitter placed at 25 ft. was audibly detectable.

What factors drive fishery yields in the Lower Shire River, Malawi ...

African Journals Online (AJOL)

The Shire River drains from Lake Malawi to the Lower Zambezi River. Annual flow is dependent mainly on lake level, partially controlled by the operation of a barrage at Liwonde to regulate flows for hydroelectricity generation in the escarpment reaches of the river. Downstream of the escarpment, the floodplains of the ...

Lower Red River Meadow Stream Restoration Project

International Nuclear Information System (INIS)

1996-05-01

As part of a continuing effort to restore anadromous fish populations in the South Fork Clearwater River basin of Idaho, Bonneville Power Administration (BPA) proposes to fund the Lower Red River Meadow Restoration Project (Project). The Project is a cooperative effort with the Idaho Soil and Water Conservation District, Nez Perce National Forest, Idaho Department of Fish and Game (IDFG), and the Nez Perce Tribe of Idaho. The proposed action would allow the sponsors to perform stream bank stabilization, aquatic and riparian habitat improvement activities on IDFG's Red River Management Area and to secure long-term conservation contracts or agreements for conducting streambank and habitat improvement activities with participating private landowners located in the Idaho County, Idaho, study area. This preliminary Environmental Assessment (EA) examines the potential environmental effects of stabilizing the stream channel, restoring juvenile fish rearing habitat and reestablishing a riparian shrub community along the stream

Changes in freshwater mussel communities linked to legacy pollution in the Lower Delaware River

Science.gov (United States)

Blakeslee, Carrie J.; Silldorff, Erik L.; Galbraith, Heather S.

2018-01-01

Freshwater mussels are among the most-imperiled organisms worldwide, although they provide a variety of important functions in the streams and rivers they inhabit. Among Atlantic-slope rivers, the Delaware River is known for its freshwater mussel diversity and biomass; however, limited data are available on the freshwater mussel fauna in the lower, non-tidal portion of the river. This section of the Delaware River has experienced decades of water-quality degradation from both industrial and municipal sources, primarily as a function of one of its major tributaries, the Lehigh River. We completed semi-quantitative snorkel surveys in 53.5 of the 121 km of the river to document mussel community composition and the continued impacts from pollution (particularly inputs from the Lehigh River) on mussel fauna. We detected changes in mussel catch per unit effort (CPUE) below the confluence of the Lehigh River, with significant declines in the dominant species Elliptio complanata (Eastern Elliptio) as we moved downstream from its confluence—CPUE dropped from 179 to 21 mussels/h. Patterns in mussel distribution around the Lehigh confluence matched chemical signatures of Lehigh water input. Specifically, Eastern Elliptio CPUE declined more quickly moving downstream on the Pennsylvania bank, where Lehigh River water input was more concentrated compared to the New Jersey bank. A definitive causal link remains to be established between the Lehigh River and the dramatic shifts in mussel community composition, warranting continued investigation as it relates to mussel conservation and restoration in the basin.

Hydraulic Geometry Analysis of the Lower Mississippi River

National Research Council Canada - National Science Library

Soar, Philip J; Thorne, Colin R; Harmar, Oliver P

2005-01-01

The hydraulic geometry of the Lower Mississippi River is primarily the product of the action of natural flows acting on the floodplain materials over centuries and millennia to form an alluvial forming a channel...

Watershed prioritization in the upper Han River basin for soil and water conservation in the South-to-North Water Transfer Project (middle route) of China.

Science.gov (United States)

Wu, Haibing

2018-01-01

Watershed prioritization with the objective of identifying critical areas to undertake soil and water conservation measures was conducted in the upper Han River basin, the water source area of approximately 95,000 km 2 for the middle route of China's South-to-North Water Transfer Project. Based on the estimated soil erosion intensity in uplands and clustering analysis of measured nutrient concentrations in rivers, the basin was grouped into very-high-, high-, moderate-, and low-priority regions for water and soil conservation, respectively. The results indicated that soil erosion was primarily controlled by topography, and nutrients in rivers were associated with land use and land cover in uplands. Also, there was large spatial disparity between soil erosion intensity in the uplands and nutrient concentrations in the rivers across the basin. Analysis was then performed to prioritize the basin by the integration of the soil erosion intensity and water quality on a GIS platform in order to identify critical areas for water and soil conservation in the basin. The identified high-priority regions which occupy 5.74% of the drainage areas need immediate attention for soil and water conservation treatments, of which 5.28% is critical for soil erosion prevention and 0.46% for water conservation. Understandings of the basin environment and pollutant loading with spatial explicit are critical to the soil and water resource conservation for the interbasin water transfer project.

Fall Chinook Salmon Survival and Supplementation Studies in the Snake River and Lower Snake River Reservoirs, 1995 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Williams, John G.; Bjomn (Bjornn), Theodore C.

1997-03-01

In 1994, the National Marine Fisheries Service and the US Fish and Wildlife Service began a cooperative study to investigate migrational characteristics of subyearling fall chinook salmon in the Snake River. The primary study objectives were to (1) determine the feasibility of estimating detection and passage survival probabilities of natural and hatchery subyearling fall chinook salmon released in the Snake River (Chapter 1), (2) investigate relationships between detection and passage survival probabilities and travel time of subyearling fall chinook salmon and environmental influences such as flow volume and water temperature (Chapter 1), (3) monitor and evaluate dispersal of hatchery subyearling chinook salmon into nearshore rearing areas used by natural fish (Chapter 2), and (4) monitor and evaluate travel time to Lower Granite Dam, growth from release in the Snake River to recapture at Lower Granite Dam, ATPase levels of fish recaptured at Lower Granite Dam, and survival from release in the free-flowing Snake River to the tailrace of Lower Granite Dam (Chapter 2).

Fall chinook salmon survival and supplementation studies in the Snake River and Lower Snake River reservoirs: Annual report 1995

International Nuclear Information System (INIS)

Williams, John G.; Bjornn, Theodore C.

1997-01-01

In 1994, the National Marine Fisheries Service and the US Fish and Wildlife Service began a cooperative study to investigate migrational characteristics of subyearling fall chinook salmon in the Snake River. The primary study objectives were to (1) determine the feasibility of estimating detection and passage survival probabilities of natural and hatchery subyearling fall chinook salmon released in the Snake River (Chapter 1), (2) investigate relationships between detection and passage survival probabilities and travel time of subyearling fall chinook salmon and environmental influences such as flow volume and water temperature (Chapter 1), (3) monitor and evaluate dispersal of hatchery subyearling chinook salmon into nearshore rearing areas used by natural fish (Chapter 2), and (4) monitor and evaluate travel time to Lower Granite Dam, growth from release in the Snake River to recapture at Lower Granite Dam, ATPase levels of fish recaptured at Lower Granite Dam, and survival from release in the free-flowing Snake River to the tailrace of Lower Granite Dam (Chapter 2)

Discharge and other hydraulic measurements for characterizing the hydraulics of Lower Congo River

Science.gov (United States)

Oberg, Kevin; Shelton, John M.; Gardiner, Ned; Jackson, P. Ryan

2009-01-01

The first direct measurements of discharge of the Lower Congo River below Malebo Pool and upstream from Kinganga, Democratic Republic of Congo (DRC) were made in July 2008 using acoustic Doppler current profilers, differential GPS, and echo sounders. These measurements were made in support of research that is attempting to understand the distribution of fish species in the Lower Congo River and reasons for separation of species within this large river. Analyses of these measurements show that the maximum depth in the Lower Congo River was in excess of 200 m and maximum water velocities were greater than 4 m/s. The discharge measured near Luozi, DRC was 35,800 m3/s, and decreased slightly beginning midway through the study. Local bedrock controls seem to have a large effect on the flow in the river, even in reaches without waterfalls and rapids. Dramatic changes in bed topography are evident in transects across the river.

Age, distribution, and formation of late cenozoic paleovalleys of the lower Colorado River and their relation to river aggradation and degradation

Science.gov (United States)

Howard, K.A.; Lundstrom, S.C.; Malmon, D.V.; Hook, S.J.

2008-01-01

Distinctive far-traveled fluvial sediment of the lower Colorado River fills 20 paleo-valleys now stranded by the river downstream of Grand Canyon as it crosses the Basin and Range Province. These sediments resulted from two or more aggradational epi sodes in Pliocene and Pleistocene times following initial incision during the early Pliocene. A review of the stratigraphic evidence of major swings in river elevation over the last 5 m.y. from alternating degradation and aggradation episodes establishes a framework for understanding the incision and filling of the paleovalleys. The paleo-valleys are found mostly along narrow bedrock canyon reaches of the river, where divides of bedrock or old deposits separate them from the modern river. The paleo-valleys are interpreted to have stemmed from periods of aggradation that filled and broadened the river valley, burying low uplands in the canyon reaches into which later channel positions were entrenched during subsequent degradation episodes. The aggradation-degradation cycles resulted in the stranding of incised river valleys that range in elevation from near the modern river to 350 m above it. ?? 2008 The Geological Society of America.

Mid-21st century projections of hydroclimate in Western Himalayas and Satluj River basin

Science.gov (United States)

Tiwari, Sarita; Kar, Sarat C.; Bhatla, R.

2018-02-01

The Himalayan climate system is sensitive to global warming and climate change. Regional hydrology and the downstream water flow in the rivers of Himalayan origin may change due to variations in snow and glacier melt in the region. This study examines the mid-21st century climate projections over western Himalayas from the Coupled Model Intercomparison Project Phase 5 (CMIP5) global climate models under Representative Concentration Pathways (RCP) scenarios (RCP4.5 and RCP8.5). All the global climate models used in the present analysis indicate that the study region would be warmer by mid-century. The temperature trends from all the models studied here are statistically significant at 95% confidence interval. Multi-model ensemble spreads show that there are large differences among the models in their projections of future climate with spread in temperature ranging from about 1.5 °C to 5 °C over various areas of western Himalayas in all the seasons. Spread in precipitation projections lies between 0.3 and 1 mm/day in all the seasons. Major shift in the timing of evaporation maxima and minima is noticed. The GFDL_ESM2G model products have been downscaled to Satluj River basin using the weather research and forecast (WRF) model and impact of climate change on streamflow has been studied. The reduction of precipitation during JJAS is expected to be > 3-6 mm/day in RCP8.5 as compared to present climate. It is expected that precipitation amount shall increase over Satluj basin in future (mid-21st century) The soil and water assessment tool (SWAT) model has been used to simulate the Satluj streamflow for the present and future climate using GFDL_ESM2G precipitation and temperature data as well as the WRF model downscaled data. The computations using the global model data show that total annual discharge from Satluj will be less in future than that in present climate, especially in peak discharge season (JJAS). The SWAT model with downscaled output indicates that during

Streamflow, water quality, and contaminant loads in the lower Charles River Watershed, Massachusetts, 1999-2000

Science.gov (United States)

Breault, Robert F.; Sorenson, Jason R.; Weiskel, Peter K.

2002-01-01

Streamflow data and dry-weather and stormwater water-quality samples were collected from the main stem of the Charles River upstream of the lower Charles River (or the Basin) and from four partially culverted urban streams that drain tributary subbasins in the lower Charles River Watershed. Samples were collected between June 1999 and September 2000 and analyzed for a number of potential contaminants including nitrate (plus nitrite), ammonia, total Kjeldahl nitrogen, phosphorus, cadmium, chromium, copper, lead, and zinc; and water-quality properties including specific conductance, turbidity, biochemical oxygen demand, fecal coliform bacteria, Entero-coccus bacteria, total dissolved solids, and total suspended sediment. These data were used to identify the major pathways and to determine the magnitudes of contaminants loads that contribute to the poor water quality of the lower Charles River. Water-quality and streamflow data, for one small urban stream and two storm drains that drain subbasins with uniform (greater than 73 percent) land use (including single-family residential, multifamily residential, and commercial), also were collected. These data were used to elucidate relations among streamflow, water quality, and subbasin characteristics. Streamflow in the lower Charles River Watershed can be characterized as being unsettled and flashy. These characteristics result from the impervious character of the land and the complex infrastructure of pipes, pumps, diversionary canals, and detention ponds throughout the watershed. The water quality of the lower Charles River can be considered good?meeting water-quality standards and guidelines?during dry weather. After rainstorms, however, the water quality of the river becomes impaired, as in other urban areas. The poor quality of stormwater and its large quantity, delivered over short periods (hours and days), together with illicit sanitary cross connections, and combined sewer overflows, results in large contaminant

Three Gorges Dam alters the Changjiang (Yangtze) river water cycle in the dry seasons: Evidence from H-O isotopes

Energy Technology Data Exchange (ETDEWEB)

Deng, Kai [School of Ocean and Earth Science, Tongji University, Shanghai, 200092 (China); State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Yang, Shouye, E-mail: syyang@tongji.edu.cn [State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061 (China); Lian, Ergang [School of Ocean and Earth Science, Tongji University, Shanghai, 200092 (China); State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Li, Chao [State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China); Yang, Chengfan; Wei, Hailun [School of Ocean and Earth Science, Tongji University, Shanghai, 200092 (China); State Key Laboratory of Marine Geology, Tongji University, Shanghai 200092 (China)

2016-08-15

As the largest hydropower project in the world, the Three Gorges Dam (TGD) has attracted great concerns in terms of its impact on the Changjiang (Yangtze) River and coastal marine environments. In this study, we measured or collected the H-O isotopic data of river water, groundwater and precipitation in the mid-lower Changjiang catchment during the dry seasons of recent years. The aim was to investigate the changes of river water cycle in response to the impoundment of the TGD. Isotopic evidences suggested that the mid-lower Changjiang river water was ultimately derived from precipitation, but dominated by the mixing of different water masses with variable sources and isotopic signals as well. The isotopic parameter “deuterium excess” (d-excess) yielded large fluctuations along the mid-lower mainstream during the initial stage of the TGD impoundment, which was inherited from the upstream water with inhomogeneous isotopic signals. However, as the reservoir water level rising to the present stage, small variability of d-excess was observed along the mid-lower mainstream. This discrepancy could be explained that the TGD impoundment had significantly altered the water cycle downstream the dam, with the rising water level increasing the residence time and enhancing the mixing of reservoir water derived from upstream. This eventually resulted in the homogenization of reservoir water, and thus small fluctuations of d-excess downstream the dam after the quasi-normal stage (2008 to present). We infer that the retention effect of large reservoirs has greatly buffered the d-excess natural variability of water cycle in large river systems. Nevertheless, more research attention has to be paid to the damming effect on the water cycle in the river, estuarine and coastal areas, especially during the dry seasons. - Highlights: • Stable H-O isotopes indicate the Changjiang river water cycle in dry seasons. • The isotopic parameter “d-excess” reveals the origins of

Three Gorges Dam alters the Changjiang (Yangtze) river water cycle in the dry seasons: Evidence from H-O isotopes

International Nuclear Information System (INIS)

Deng, Kai; Yang, Shouye; Lian, Ergang; Li, Chao; Yang, Chengfan; Wei, Hailun

2016-01-01

As the largest hydropower project in the world, the Three Gorges Dam (TGD) has attracted great concerns in terms of its impact on the Changjiang (Yangtze) River and coastal marine environments. In this study, we measured or collected the H-O isotopic data of river water, groundwater and precipitation in the mid-lower Changjiang catchment during the dry seasons of recent years. The aim was to investigate the changes of river water cycle in response to the impoundment of the TGD. Isotopic evidences suggested that the mid-lower Changjiang river water was ultimately derived from precipitation, but dominated by the mixing of different water masses with variable sources and isotopic signals as well. The isotopic parameter “deuterium excess” (d-excess) yielded large fluctuations along the mid-lower mainstream during the initial stage of the TGD impoundment, which was inherited from the upstream water with inhomogeneous isotopic signals. However, as the reservoir water level rising to the present stage, small variability of d-excess was observed along the mid-lower mainstream. This discrepancy could be explained that the TGD impoundment had significantly altered the water cycle downstream the dam, with the rising water level increasing the residence time and enhancing the mixing of reservoir water derived from upstream. This eventually resulted in the homogenization of reservoir water, and thus small fluctuations of d-excess downstream the dam after the quasi-normal stage (2008 to present). We infer that the retention effect of large reservoirs has greatly buffered the d-excess natural variability of water cycle in large river systems. Nevertheless, more research attention has to be paid to the damming effect on the water cycle in the river, estuarine and coastal areas, especially during the dry seasons. - Highlights: • Stable H-O isotopes indicate the Changjiang river water cycle in dry seasons. • The isotopic parameter “d-excess” reveals the origins of

Tribute to Hans Sann

CERN Multimedia

2003-01-01

1945-2003 Hans Sann, an internationally recognized scientist, beloved colleague and friend, died in a tragic car accident, on May 27th, on one of his many travels to CERN. Employed at GSI, in Darmstadt, since 1979, Hans Sann devoted most of his scientific career to the development of large size gas detectors for nuclear and high-energy physics experiments at GSI, CERN and Berkeley. One of his main achievements, among many others, was the famous MUSIC detector, on which several projects at GSI, Berkeley and other research Institutes were based. The innovative results obtained in the study of the fluid-gas transition in nuclear matter would not have been possible without his contribution and the application of the MUSIC detector. A member of the ALICE Collaboration since 1996, Hans was leading two main ALICE sub-programmes, the development of the gas system and the cooling system for the TPC detector. In addition, he was involved in the development of a new technological concept for the resistor chain of the ...

Storage and remobilization of suspended sediment in the lower amazon river of Brazil

Science.gov (United States)

Meade, R.H.; Dunne, T.; Richey, J.E.; Santos, U.De. M.; Salati, E.

1985-01-01

In the lower Amazon River, suspended sediment is stored during rising stages of the river and resuspended during falling river stages. The storage and resuspension in the reach are related to the mean slope of the flood wave on the river surface; this slope is smaller during rising river stages than during falling stages. The pattern of storage and resuspension damps out the extreme values of high and low sediment discharge and tends to keep them near the mean value between 3.0 ?? 106 and 3.5 ?? 106 metric tons per day. Mean annual discharge of suspended sediment in the lower Amazon is between 1.1 ?? 109 and 1.3 ?? 109 metric tons per year.

Records of human occupation from Pleistocene river terrace and aeolian sediments in the Arneiro depression (Lower Tejo River, central eastern Portugal)

DEFF Research Database (Denmark)

Cunha, Pedro P.; Almeida, Nelson A.C.; Aubry, Thierry

2012-01-01

In the uppermost reach of the Lower Tejo River (eastern central Portugal), where the river crosses two quartzite ridges that separate the Ródão (upstream) and Arneiro (downstream) depressions, Palaeolithic artefacts have been recovered from three lower river terrace levels and a cover unit of aeo...

Record of Lower Gondwana megafloral assemblage from Lower Kamthi Formation of Ib River Coalfield, Orissa, India

Energy Technology Data Exchange (ETDEWEB)

Goswami, S. [Birbal Sahni Institute of Paleobotany, Lucknow (India)

2006-03-15

Recent investigations carried out in the Ib River Coalfield, Mahanadi Master Basin, Orissa, identified some fossiliferous beds in the Lower Gondwana deposits. Two exposures of the Lower Kamthi Formation yielded diverse and abundant plant remains, which include Neomariopteris, Vertebraria, and a scale leaf along with 14 Glossopteris species otherwise mapped as Barren Measures and Upper Kamthi formations. Glossopteris indica dominates the flora (22.78%) followed by G. communis (17.72%) and G. browniana (13.92%). Based on megafloral assemblages, different beds exposed at Gopalpur and Laxamanpur Pahar are assigned here to the Lower Kamthi Formation (Late Permian). The floristic composition suggests that a warm and humid climate prevailed during the Late Permian. The status of the Kamthi Formation in the Ib River Coalfield has been redefined in the present study.

Creating Flood Inundation Maps For Lower Sakarya River

Directory of Open Access Journals (Sweden)

Osman Sönmez

2013-06-01

Full Text Available The Sakarya River Basin in Turkey frequently floods. The allure of riverside settlement and of nutrient-rich riverbank soil has led to extensive residential and agricultural development in flood plains. In this study, the 100 years return period possible flood carrying capacites of last 113 km of the Lower Sakarya Riverbed were investigated, also dam break and risk analyses were performed by applying different scenarios for the floods likely to occur. Flooding scenarios and water depth within the floodplain during these scenarios were calculated with the HEC-RAS software program and results were converted into a map in HEC-GeoRAS,ArcGIS 9x and ArcView 3.2 programs. As a result, it was observed that the Lower Sakarya River is susceptible to flooding. Recent observations of the study area confirm the study findings. This study tries to underscore the importance of taking into account the different scenarios regarding flood prevention and reduction studies.

Fish depth distributions in the Lower Mississippi River

Science.gov (United States)

Killgore, K. J.; Miranda, Leandro E.

2014-01-01

A substantial body of literature exists about depth distribution of fish in oceans, lakes and reservoirs, but less is known about fish depth distribution in large rivers. Most of the emphasis on fish distributions in rivers has focused on longitudinal and latitudinal spatial distributions. Knowledge on depth distribution is necessary to understand species and community habitat needs. Considering this void, our goal was to identify patterns in fish benthic distribution along depth gradients in the Lower Mississippi River. Fish were collected over 14 years in depths down to 27 m. Fish exhibited non-random depth distributions that varied seasonally and according to species. Species richness was highest in shallow water, with about 50% of the 62 species detected no longer collected in water deeper than 8 m and about 75% no longer collected in water deeper than 12 m. Although richness was highest in shallow water, most species were not restricted to shallow water. Rather, most species used a wide range of depths. A weak depth zonation occurred, not as strong as that reported for deep oceans and lakes. Larger fish tended to occur in deeper water during the high-water period of an annual cycle, but no correlation was evident during the low-water period. The advent of landscape ecology has guided river research to search for spatial patterns along the length of the river and associated floodplains. Our results suggest that fish assemblages in large rivers are also structured vertically. 

Lower Columbia River Terminal Fisheries Research Project : Final Environmental Assessment.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1995-04-01

This notice announces BPA`S`s decision to fund the Oregon Department of Fish and Wildlife (ODFW), the Washington Department of Fish and Wildlife (WDFW), and the Clatsop Economic Development Committee for the Lower Columbia River Terminal Fisheries Research Project (Project). The Project will continue the testing of various species/stocks, rearing regimes, and harvest options for terminal fisheries, as a means to increase lower river sport and commercial harvest of hatchery fish, while providing both greater protection of weaker wild stocks and increasing the return of upriver salmon runs to potential Zone 6 Treaty fisheries. The Project involves relocating hatchery smolts to new, additional pen locations in three bays/sloughs in the lower Columbia River along both the Oregon and Washington sides. The sites are Blind Slough and Tongue Point in Clatsop County, Oregon, and Grays Bay/Deep River, Wahkiakum County, Washington. The smolts will be acclimated for various lengths of time in the net pens and released from these sites. The Project will expand upon an existing terminal fisheries project in Youngs Bay, Oregon. The Project may be expanded to other sites in the future, depending on the results of this initial expansion. BPA`S has determined the project is not a major Federal action significantly affecting the quality of the human environment, within the meaning of the National Environmental Policy Act (NEPA) of 1969. Therefore, the preparation of an environmental impact statement is not required, and BPA`S is issuing this FONSI.

Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1997 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Hoefs, Nancy (Nez Perce Tribe, Department of Fisheries Resource Management, Lapwai, ID)

2004-02-01

During 1997 the first phase of the Nez Perce Tribe White Sturgeon Project was completed and the second phase was initiated. During Phase I the ''Upper Snake River White Sturgeon Biological Assessment'' was completed, successfully: (1) compiling regional white sturgeon management objectives, and (2) identifying potential mitigation actions needed to rebuild the white sturgeon population in the Snake River between Hells Canyon and Lower Granite dams. Risks and uncertainties associated with implementation of these potential mitigative actions could not be fully assessed because critical information concerning the status of the population and their habitat requirements were unknown. The biological risk assessment identified the fundamental information concerning the white sturgeon population that is needed to fully evaluate the effectiveness of alternative mitigative strategies. Accordingly, a multi-year research plan was developed to collect specific biological and environmental data needed to assess the health and status of the population and characterize habitat used for spawning and rearing. In addition, in 1997 Phase II of the project was initiated. White sturgeon were captured, marked, and population data were collected between Lower Granite Dam and the mouth of the Salmon River. During 1997, 316 white sturgeon were captured in the Snake River. Of these, 298 were marked. Differences in the fork length frequency distributions of the white sturgeon were not affected by collection method. No significant differences in length frequency distributions of sturgeon captured in Lower Granite Reservoir and the mid- and upper free-flowing reaches of the Snake River were detected. The length frequency distribution indicated that white sturgeon between 92 and 183 cm are prevalent in the reaches of the Snake River that were sampled. However, white sturgeon >183 have not changed markedly since 1970. I would speculate that some factor other than past over

Measurement of flows for two irrigation districts in the lower Colorado River basin, Texas

Science.gov (United States)

Coplin, L.S.; Liscum, Fred; East, J.W.; Goldstein, L.B.

1996-01-01

The Lower Colorado River Authority sells and distributes water for irrigation of rice farms in two irrigation districts, the Lakeside district and the Gulf Coast district, in the lower Colorado River Basin of Texas. In 1993, the Lower Colorado River Authority implemented a water-measurement program to account for the water delivered to rice farms and to promote water conservation. During the rice-irrigation season (summer and fall) of 1995, the U.S. Geological Survey measured flows at 30 sites in the Lakeside district and 24 sites in the Gulf Coast district coincident with Lower Colorado River Authority measuring sites. In each district, the Survey made essentially simultaneous flow measurements with different types of meters twice a day once in the morning and once in the afternoon at each site on selected days for comparison with Lower Colorado River Authority measurements. One-hundred pairs of corresponding (same site, same date) Lower Colorado River Authority and U.S. Geological Survey measurements from the Lakeside district and 104 measurement pairs from the Gulf Coast district are compared statistically and graphically. For comparison, the measurement pairs are grouped by irrigation district and further subdivided by the time difference between corresponding measurements less than or equal to 1 hour or more than 1 hour. Wilcoxon signed-rank tests (to indicate whether two groups of paired observations are statistically different) on Lakeside district measurement pairs with 1 hour or less between measurements indicate that the Lower Colorado River Authority and U.S. Geological Survey measurements are not statistically different. The median absolute percent difference between the flow measurements is 5.9 percent; and 33 percent of the flow measurements differ by more than 10 percent. Similar statistical tests on Gulf Coast district measurement pairs with 1 hour or less between measurements indicate that the Lower Colorado River Authority and U.S. Geological

LCREP catch records - Lower Columbia River Ecosystem Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — 1) The purpose of this project is to document juvenile salmon habitat occurrence in the Lower Columbia River and estuary, and examine how habitat conditions...

LCREP prey data - Lower Columbia River Ecosystem Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — 1) The purpose of this project is to document juvenile salmon habitat occurrence in the Lower Columbia River and estuary, and examine how habitat conditions...

LCREP growth rates - Lower Columbia River Ecosystem Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — 1) The purpose of this project is to document juvenile salmon habitat occurrence in the Lower Columbia River and estuary, and examine how habitat conditions...

Physical characteristics of the lower San Joaquin River, California, in relation to white sturgeon spawning habitat, 2011–14

Science.gov (United States)

Marineau, Mathieu D.; Wright, Scott A.; Whealdon-Haught, Daniel R.; Kinzel, Paul J.

2017-07-19

The U.S. Fish and Wildlife Service confirmed that white sturgeon (Acipenser transmontanus) recently spawned in the lower San Joaquin River, California. Decreases in the San Francisco Bay estuary white sturgeon population have led to an increased effort to understand their migration behavior and habitat preferences. The preferred spawning habitat of other white sturgeon (for example, those in the Columbia and Klamath Rivers) is thought to be areas that have high water velocity, deep pools, and coarse bed material. Coarse bed material (pebbles and cobbles), in particular, is important for the survival of white sturgeon eggs and larvae. Knowledge of the physical characteristics of the lower San Joaquin River can be used to preserve sturgeon spawning habitat and lead to management decisions that could help increase the San Francisco Bay estuary white sturgeon population.Between 2011 and 2014, the U.S. Geological Survey, in cooperation with the U.S. Fish and Wildlife Service, assessed selected reaches and tributaries of the lower river in relation to sturgeon spawning habitat by (1) describing selected spawning reaches in terms of habitat-related physical characteristics (such as water depth and velocity, channel slope, and bed material) of the lower San Joaquin River between its confluences with the Stanislaus and Merced Rivers, (2) describing variations in these physical characteristics during wet and dry years, and (3) identifying potential reasons for these variations.The lower San Joaquin River was divided into five study reaches. Although data were collected from all study reaches, three subreaches where the USFWS collected viable eggs at multiple sites in 2011–12 from Orestimba Creek to Sturgeon Bend were of special interest. Water depth and velocity were measured using two different approaches—channel cross sections and longitudinal profiles—and data were collected using an acoustic Doppler current profiler.During the first year of data collection (water

Lower pole anatomy and mid-renal-zone classification applied to flexible ureteroscopy: experimental study using human three-dimensional endocasts.

Science.gov (United States)

Marroig, Bruno; Favorito, Luciano Alves; Fortes, Marco A; Sampaio, Francisco J B

2015-12-01

The aim of this study was to analyze the anatomy of the inferior pole collecting system and the mid-renal-zone classification in human endocasts applied to flexible ureteroscopy. 170 three-dimensional polyester resin endocasts of the kidney collecting system were obtained from 85 adult cadavers. We divided the endocasts into four groups: A1--kidney midzone (KM), drained by minor calices (mc) that are dependent on the superior or the inferior caliceal groups; A2--KM drained by crossed calices; B1--KM drained by a major caliceal group independent of both the superior and inferior groups; and B2--KM drained by mc entering directly into the renal pelvis. We studied the number of calices, the angle between the lower infundibulum and renal pelvis and the angle between the lower infundibulum and the inferior mc (LIICA). Means were statistically compared using ANOVA and the unpaired T test (p kidney midzone drained by minor calices that are dependent on the superior or on the inferior caliceal groups presented at least two restrictive anatomical features. The mid-renal-zone classification was predictive of anatomical risk factors for lower pole ureteroscopy difficulties.

The lower San Pedro River: hydrology and flow restoration for biodiversity conservation

Science.gov (United States)

Jeanmarie Haney

2005-01-01

The lower San Pedro River, downstream from Benson, is a nearly unfragmented habitat containing perennial flow reaches that support riparian vegetation that serve as “stepping stones” for migratory species. The Nature Conservancy has purchased farm properties and retired agricultural pumping along the lower river, based largely on results from hydrologic analyses...

Aquifer depletion in the Lower Mississippi River Basin: challenges and solutions

Science.gov (United States)

The Lower Mississippi River Basin (LMRB) is a nationally- and internationally-important region of intensive agricultural production that relies heavily on the underlying Mississippi River Valley Alluvial Aquifer (MRVAA) for row crop irrigation. Extensive irrigation coupled with the region’s geology ...

Floodplain lakes and alluviation cycles of the lower Colorado River

Science.gov (United States)

Malmon, D.; Felger, T. J.; Howard, K. A.

2007-05-01

The broad valleys along the lower Colorado River contain numerous bodies of still water that provide critical habitat for bird, fish, and other species. This chain of floodplain lakes is an important part of the Pacific Flyway - the major north-south route of travel for migratory birds in the western Hemisphere - and is also used by many resident bird species. In addition, isolated floodplain lakes may provide the only viable habitat for endangered native fish such as the razorback sucker, vulnerable to predation by introduced species in the main stem of the Colorado River. Floodplain lakes typically occupy former channel courses of the river and formed as a result of river meandering or avulsion. Persistent fluvial sediment deposition (aggradation) creates conditions that favor rapid formation and destruction of floodplain lakes, while long term river downcutting (degradation) inhibits their formation and evolution. New radiocarbon dates from wood recovered from drill cores near Topock, AZ indicate that the river aggraded an average of 3 mm/yr in the middle and late Holocene. Aggradational conditions before Hoover Dam was built were associated with rapid channel shifting and frequent lake formation. Lakes had short life spans due to rapid infilling with fine-grained sediment during turbid floods on the unregulated Colorado River. The building of dams and of armored banks had a major impact on floodplain lakes, not only by drowning large portions of the valley beneath reservoirs, but by preventing new lake formation in some areas and accelerating it in others. GIS analyses of three sets of historical maps show that both the number and total area of isolated (i.e., not linked to the main channel by a surface water connection) lakes in the lower Colorado River valley increased between 1902 and the 1950s, and then decreased though the 1970s. River bed degradation below dams inhibits channel shifting and floodplain lake formation, and the capture of fines behind the

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix I: Economics

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

33 CFR 165.812 - Security Zones; Lower Mississippi River, Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans...

Science.gov (United States)

2010-07-01

... River, Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. 165.812 Section 165.812 Navigation..., Southwest Pass Sea Buoy to Mile Marker 96.0, New Orleans, LA. (a) Location. Within the Lower Mississippi... Lower Mississippi River mile marker 96.0 in New Orleans, Louisiana. These moving security zones...

Salinization Sources Along the Lower Jordan River Under Draught Conditions

Science.gov (United States)

Holtzman, R.; Shavit, U.; Segal, M.; Vengosh, A.; Farber, E.; Gavrieli, I.

2003-12-01

The Lower Jordan River, once a flowing freshwater river, is suffering from an ongoing reduction of discharge and water quality. The river flows between the Sea of Galilee and the Dead Sea, an aerial distance of about 105 Km. The severe reduction is caused by an excessive exploitation of its sources and diversion of sewage and agricultural drainage into the river. The extreme low flows and low water quality threaten the natural existence of the river and its potential use for agriculture. In spite of its importance, little research has been done in the river. The objectives of the study were to measure the discharge and water composition along the river and to evaluate the main sources that control its flow and chemical characteristics. The hypothesis of the study was that interaction with subsurface flows significantly affects the river flow and chemical composition. The research is based on a detailed field study, which included flow rate measurements in the river and its tributaries, water sampling and analysis and mass balance calculations of water and solutes. A portable Acoustic Doppler Velocimeter (ADV) was used to measure velocities and bathymetry at different locations across the river sections. Due to accessibility constraints, a floating traverse construction, which enables the ADV's deployment from one bank of the river, was developed. It was found that flow rate ranges between 500-1,100 L/s in northern (upstream) sections and 300-1,650 L/s in the south. This low discharge represents a significant reduction from historical values and is lower than recent published estimations. This research represents base flows only, as the measurements were done during a period of two consecutive draught years. Calculated mass balance of water flows in the northern sections shows that the subsurface source contributes to the river around 200-670 L/s (30-80% of the river flow). Calculations of solute balance show that the subsurface flows add 20-50% of the mass of

Agricultural water conservation programs in the lower Colorado River Authority

International Nuclear Information System (INIS)

Kabir, J.

1993-01-01

Rice irrigation is the largest user of water within the area served by the Lower Colorado River Authority (LCRA), accounting for approximately 75 percent of total annual surface and ground water demands. In an average year, about 30 percent of surface water supplied to rice irrigation is satisfied with water released from the storage in the Highland Lakes located at the upstream reaches of the Lower Colorado River and its tributaries. During a severe drought, the demand for stored water could be as much as 70 percent of annual rice irrigation demand. LCRA owns and operates two irrigation canal systems which together supply water to irrigate 60,000 acres of rice each year. These irrigation systems are the Lakeside and Gulf Coast Irrigation Divisions. The Lakeside system is located in Colorado and Wharton Counties and the Gulf Coast system is located in Wharton and Matagorda Counties. In the 1987 and 1989, the Lower Colorado River Authority Board of Directors authorized implementation and funding for Canal Rehabilitation Project and Irrigation Water Measurement Project respectively. These two projects are key initiatives to agricultural water conservation goals established in the LCRA Water Management Plan and Water Conservation Policy. In addition LCRA participated actively in agricultural water conservation research projects and technology transfer activities

Potential effects of structural controls and street sweeping on stormwater loads to the lower Charles River, Massachusetts

Science.gov (United States)

Zarriello, Phillip J.; Breault, Robert F.; Weiskel, Peter K.

2002-01-01

The water quality of the lower Charles River is periodically impaired by combined sewer overflows (CSOs) and non-CSO stormwater runoff. This study examined the potential non-CSO load reductions of suspended solids, fecal coliform bacteria, total phosphorus, and total lead that could reasonably be achieved by implementation of stormwater best management practices, including both structural controls and systematic street sweeping. Structural controls were grouped by major physical or chemical process; these included infiltration-filtration (physical separation), biofiltration-bioretention (biological mechanisms), or detention-retention (physical settling). For each of these categories, upper and lower quartiles, median, and average removal efficiencies were compiled from three national databases of structural control performance. Removal efficiencies obtained indicated a wide range of performance. Removal was generally greatest for infiltration-filtration controls and suspended solids, and least for biofiltration-bioretention controls and fecal coliform bacteria. Street sweeping has received renewed interest as a water-quality control practice because of reported improvements in sweeper technology and the recognition that opportunities for implementing structural controls are limited in highly urbanized areas. The Stormwater Management Model that was developed by the U.S. Geological Survey for the lower Charles River Watershed was modified to simulate the effects of street sweeping in a single-family land-use basin. Constituent buildup and washoff variable values were calibrated to observed annual and storm-event loads. Once calibrated, the street sweeping model was applied to various permutations of four sweeper efficiencies and six sweeping frequencies that ranged from every day to once every 30 days. Reduction of constituent loads to the lower Charles River by the combined hypothetical practices of structural controls and street sweeping was estimated for a range

Ecosystem effects in the Lower Mississippi River Basin: Chapter L in 2011 Floods of the Central United States

Science.gov (United States)

Turnipseed, D. Phil; Allen, Yvonne C.; Couvillion, Brady R.; McKee, Karen L.; Vervaeke, William C.

2014-01-01

The 2011 Mississippi River flood in the Lower Mississippi River Basin was one of the largest flood events in recorded history, producing the largest or next to largest peak streamflow for the period of record at a number of streamgages on the lower Mississippi River. Ecosystem effects include changes to wetlands, nutrient transport, and land accretion and sediment deposition changes. Direct effects to the wetland ecosystems in the Lower Mississippi River Basin were minimized because of the expansive levee system built to pass floodwaters. Nutrients carried by the Mississippi River affect water quality in the Lower Mississippi River Basin. During 2011, nutrient fluxes in the lower Mississippi River were about average. Generally, nutrient delivery of the Mississippi and Atchafalaya Rivers contributes to the size of the hypoxic zone in the Gulf of Mexico. Based on available limited post-flood satellite imagery, some land expansion in both the Wax Lake and Atchafalaya River Deltas was observed. A wetland sediment survey completed in June 2011 indicated that recent sediment deposits were relatively thicker in the Atchafalaya and Mississippi River (Birdsfoot) Delta marshes compared to marshes farther from these rivers.

Relations of water-quality constituent concentrations to surrogate measurements in the lower Platte River corridor, Nebraska, 2007 through 2011

Science.gov (United States)

Schaepe, Nathaniel J.; Soenksen, Philip J.; Rus, David L.

2014-01-01

The lower Platte River, Nebraska, provides drinking water, irrigation water, and in-stream flows for recreation, wildlife habitat, and vital habitats for several threatened and endangered species. The U.S. Geological Survey (USGS), in cooperation with the Lower Platte River Corridor Alliance (LPRCA) developed site-specific regression models for water-quality constituents at four sites (Shell Creek near Columbus, Nebraska [USGS site 06795500]; Elkhorn River at Waterloo, Nebr. [USGS site 06800500]; Salt Creek near Ashland, Nebr. [USGS site 06805000]; and Platte River at Louisville, Nebr. [USGS site 06805500]) in the lower Platte River corridor. The models were developed by relating continuously monitored water-quality properties (surrogate measurements) to discrete water-quality samples. These models enable existing web-based software to provide near-real-time estimates of stream-specific constituent concentrations to support natural resources management decisions. Since 2007, USGS, in cooperation with the LPRCA, has continuously monitored four water-quality properties seasonally within the lower Platte River corridor: specific conductance, water temperature, dissolved oxygen, and turbidity. During 2007 through 2011, the USGS and the Nebraska Department of Environmental Quality collected and analyzed discrete water-quality samples for nutrients, major ions, pesticides, suspended sediment, and bacteria. These datasets were used to develop the regression models. This report documents the collection of these various water-quality datasets and the development of the site-specific regression models. Regression models were developed for all four monitored sites. Constituent models for Shell Creek included nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, acetochlor, suspended sediment, and Escherichia coli (E. coli) bacteria. Regression models that were developed for the Elkhorn River included nitrate plus nitrite, total Kjeldahl nitrogen, total phosphorus

Monitoring and mapping selected riparian habitat along the lower Snake River

Energy Technology Data Exchange (ETDEWEB)

Downs, J. L; Tiller, B. L [Pacific Northwest Lab., Richland, WA (United States); Witter, M. [Shannon and Wilson, Inc., Seattle, WA (United States). Geotechnical and Environmental Consultants, Seattle, Washington (United States); Mazaika, R. [Corps of Engineers, Portland, OR (United States)

1996-01-01

Studies in this document were initiated to establish baseline information on riparian and wetland habitat conditions at the areas studied under the current reservoir operations on the lower Snake River. Two approaches were used to assess habitat at 28 study sites selected on the four pools on the lower Snake River. These areas all contribute significant riparian habitat along the river, and several of these areas are designated habitat management units. At 14 of the 28 sites, we monitored riparian habitat on three dates during the growing season to quantify vegetation abundance and composition along three transects: soil nutrients, moisture, and pH and water level and pH. A second approach involved identifying any differences in the extent and amount of riparian/wetland habitat currently found at the study areas from that previously documented. We used both ground and boat surveys to map and classify the changes in vegetative cover along the shoreline at the 14 monitoring sites and at 14 additional sites along the lower Snake selected to represent various riparian/wetland habitat conditions. Results of these mapping efforts are compared with maps of cover types previously generated using aerial photography taken in 1987.

Designing forward with an eye to the past: Morphogenesis of the lower Yuba River

Science.gov (United States)

James, L. Allan

2015-12-01

The early geomorphic evolution of the lower Yuba River (LYR), northern California, up to 1906 is reconstructed using cartographic, documentary, topographic, and stratigraphic evidence. The importance of early river mining is identified along with rates and patterns of floodplain aggradation and channel incision at the turn of the 20th century. The LYR is a classic example of anthropogeomorphic transformation of a river by episodic hydraulic mining sedimentation. This was followed by channelization, damming, dredging, and other engineering works to redirect, contain, and stabilize channels. These geomorphic changes and engineering controls continue to govern channel and floodplain form and process, control the trajectory of river responses, and constrain flood control, water quality, and aquatic ecosystem management options. Returning a river system to a prior condition should not be the primary goal of river rehabilitation projects, especially if hydrologic inputs have substantially changed. Reconstructing former conditions may be impractical and unsustainable under modern circumstances. Instead, fluvial systems should be designed and managed for present inputs and processes while anticipating future conditions. Rapid changes in land use and climate that generate changes in runoff and sediment loadings are likely to generate morphological instability, and these changes should be considered in the design and management of fluvial systems. The past geomorphic evolution of fluvial systems should also be considered in design and management decisions to recognize trajectories and suppressed tendencies. Recognition of trends and system vulnerabilities may avoid potential blunders, such as removing critical stabilizing works. Complex causalities may be difficult to reconstruct from geomorphic form alone, however, due to process-form dynamics. Detailed research on the geomorphic and engineering history of a river is essential, therefore, if substantial changes and

Concentrations and transport of suspended sediment, nutrients, and pesticides in the lower Mississippi-Atchafalaya River subbasin during the 2011 Mississippi River flood, April through July

Science.gov (United States)

Welch, Heather L.; Coupe, Richard H.; Aulenbach, Brent T.

2014-01-01

High streamflow associated with the April–July 2011 Mississippi River flood forced the simultaneous opening of the three major flood-control structures in the lower Mississippi-Atchafalaya River subbasin for the first time in history in order to manage the amount of water moving through the system. The U.S. Geological Survey (USGS) collected samples for analysis of field properties, suspended-sediment concentration, particle-size, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, and up to 136 pesticides at 11 water-quality stations and 2 flood-control structures in the lower Mississippi-Atchafalaya River subbasin from just above the confluence of the upper Mississippi and Ohio Rivers downstream from April through July 2011. Monthly fluxes of suspended sediment, suspended sand, total nitrogen, nitrate plus nitrite, total phosphorus, orthophosphate, atrazine, simazine, metolachlor, and acetochlor were estimated at 9 stations and 2 flood-control structures during the flood period. Although concentrations during the 2011 flood were within the range of what has been observed historically, concentrations decreased during peak streamflow on the lower Mississippi River. Prior to the 2011 flood, high concentrations of suspended sediment and nitrate were observed in March 2011 at stations downstream of the confluence of the upper Mississippi and Ohio Rivers, which probably resulted in a loss of available material for movement during the flood. In addition, the major contributor of streamflow to the lower Mississippi-Atchafalaya River subbasin during April and May was the Ohio River, whose water contained lower concentrations of suspended sediment, pesticides, and nutrients than water from the upper Mississippi River. Estimated fluxes for the 4-month flood period were still quite high and contributed approximately 50 percent of the estimated annual suspended sediment, nitrate, and total phosphorus fluxes in 2011; the largest fluxes were estimated at

River-flow predictions for the South African mid-summer using a coupled general circulation model

CSIR Research Space (South Africa)

Olivier, C

2013-09-01

Full Text Available African Society for Atmospheric Sciences (SASAS) 2013 http://sasas.ukzn.ac.za/homepage.aspx 1 Tel: +27 12 367 6008 Fax: +27 12 367 6189 Email: cobus.olivier@weathersa.co.za RIVER-FLOW PREDICTIONS FOR THE SOUTH AFRICAN MID-SUMMER USING A COUPLED... for Atmospheric Sciences (SASAS) 2013 http://sasas.ukzn.ac.za/homepage.aspx 2 drops to 127 nationally and 65 stations for the area of interest. A recent coupled modeling system developed at the South African Weather Service (SAWS), that utilizes...

Proposed modifications to the Lower Mokelumne River Project, California: FERC Project No. 2916-004

International Nuclear Information System (INIS)

1993-11-01

This final environmental impact statement (FEIS) has been prepared for the Federal Energy Regulatory Commission (Commission) to consider modifications to the existing Lower Mokelumne River Project (LMRP) (FERC Project No. 2916-004) in California. Chinook salmon and steelhead trout populations in the lower Mokelumne River have experienced recent declines and fish kills associated, in part, with discharges from Camanche Dam. The California Department of Fish and Game and the California Sportfishing Protection Alliance have asked the Commission to investigate and correct these problems. A wide range of different mitigation actions has been proposed by parties participating in the scoping of this proceeding, and staff has evaluated these proposed actions in this assessment. The staff is recommending a combination of flow and non-flow modifications to the existing license, including new minimum flow and minimum pool elevation requirements at Camanche Reservoir, ramping rates on dam releases, interim attraction and out-migrant spike flows, instream habitat improvements, and a series of studies and monitoring to determine feasible means for solving off-site fish passage problems

LCREP genetic stock ID - Lower Columbia River Ecosystem Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — 1) The purpose of this project is to document juvenile salmon habitat occurrence in the Lower Columbia River and estuary, and examine how habitat conditions...

LCREP chemistry and lipids - Lower Columbia River Ecosystem Monitoring Project

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — 1) The purpose of this project is to document juvenile salmon habitat occurrence in the Lower Columbia River and estuary, and examine how habitat conditions...

Strategic Floodplain Reconnection Along the Lower Tisza and Lower Illinois Rivers: Identifying Opportunities, Tradeoffs, and Limitations

Science.gov (United States)

Guida, R.; Remo, J. W.; Secchi, S.; Swanson, T.; Kiss, T.

2015-12-01

During the late 19th and into the 20th Centuries, the Tisza and Illinois Rivers were highly altered through the construction of levees and dams to reclaim their floodplain-wetland systems for agriculture and to facilitate navigation. In recent decades, flood levels have continued to rise due to aggradation on the confined floodplains reducing flood-conveyance capacity. As a result, "Room for the River" proposals have gained more prominence. Our overarching hypothesis is that strategically reconnecting these rivers to their floodplains will reduce flood levels and increase ecological habitat while limiting socioeconomic impacts. In this study, we assessed several reconnection scenarios, including levee setbacks and removals, for the Lower Tisza River (LTR; Hungary) and the Lower Illinois River (LIR; Illinois, USA). To model water-surface elevations (WSELs) for the 5- through 500-year flood events, we employed HEC-RAS (1D) and SOBEK (1D/2D) hydraulic models. To determine socioeconomic tradeoffs using these modeled WSELs, we developed a corresponding suite of expected annual damages (EADs) using FEMA's Hazus-MH flood-loss modeling software for buildings and integrated geospatial and soil productivity indices to estimate agricultural losses. To assess ecosystem benefits of reconnection along the LTR, we used historic wetland extent as a proxy for increasing needed floodplain habitats. For the LIR, we performed habitat screening using Land Capability Potential Index and other assessment tools to estimate potential ecosystem benefits. Results indicate that levee removal and/or setbacks may reduce flood heights up to 1.6 m along the LTR and over 1.0 m along the LIR. While urban areas have the highest EADs, several lower-production agricultural areas show potential for reducing flood heights while minimizing damages. Strategic-floodplain reconnection benefits along the LTR and LIR include over half of historically-significant wetlands being reconnected and the creation of

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix C: Water Quality

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower-Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix K: Real Estate

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects-on four lower Snake River salmon and steelhead stocks listed for protection- under the Endangered Species Act (ESA). The U.S...

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix J: Plan Formulation

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Evaluate Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2002-2003 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Faler, Michael P. (US Fish and Wildlife Service, Idaho Fishery Resource Office, Ahsahka, ID); Mendel, Glen W.; Fulton, Carl (Washington Department of Fish and Wildlife, Fish Management Division, Dayton, WA)

2004-04-01

We collected 279 adult bull trout (Salvelinus confluentus) in the Tucannon River during the Spring and Fall of 2003. Passive Integrated Transponder (PIT) tags were inserted in 191 of them, and we detected existing PIT tags in an additional 31bull trout. Thirty five of these were also surgically implanted with radio-tags, and we monitored the movements of these fish throughout the year. Fourteen radio-tags were recovered shortly after tagging, and as a result, 21 remained in the river through December 31, 2003. Four bull trout that were radio-tagged in spring 2002 were known to survive and carry their tags through the spring and/or summer of 2003. One of these fish spent the winter near river mile (RM) 13.0; the other 3 over-wintered in the vicinity of the Tucannon Hatchery between RM 34 and 36. Twenty-one radio tags from bull trout tagged in 2002 were recovered during the spring and summer, 2003. These tags became stationary the winter of 2002/2003, and were recovered between RM 11 and 55. We were unable to recover the remaining 15 tags from 2002. During the month of July, radio-tagged bull trout exhibited a general upstream movement into the upper reaches of the Tucannon subbasin. We observed some downstream movements of radio-tagged bull trout in mid to late September and throughout October. By late November and early December, radio tagged bull trout were relatively stationary, and were distributed from the headwaters downstream to river mile 6.4, near Lower Monumental Pool. As in 2002, we did not conduct work associated with objectives 2, 3, or 4 of this study, because we were unable to monitor migratory movement of radio-tagged bull trout into the Federal hydropower system on the mainstem Snake River. Transmission tests of submerged ATS model F1830 radio-tags in Lower Granite Pool showed that audible detection and individual tag identification was possible at depths of 20 and 30 ft. Tests were conducted using an ATS R-4000 Receiver equipped with an &apos

High-resolution sequence stratigraphic correlation of the braided river and vertical distribution characteristics of sand body-Take upper member of saihan formation of lower cretaceous in Bayanwula deposit, for instance

International Nuclear Information System (INIS)

Dai Mingjian; Peng Yunbiao; Yang Jianxin; Shen Kefeng

2014-01-01

In recent years, the high-resolution sequence stratigraphy of which reference surface is base level cycle get rapid development. Its biggest advantage is the ability to apply to the continental sedimentary basins controlled by multiple factors, especially applied to the thin layer contrast of the paleochannel sandstone type uranium reservoir. This paper, by using drill core and logging data, has made the high resolution sequence stratigraphy studies on braided river uranium reservoir of Upper Member of Saihan Formation of Lower Cretaceous (Kls2) in Bayanwula deposit and identified the base level cycle interface. The study interval is divided into one long-term cycle and seven mid-term base level cycle, and high-resolution time stratigraphic framework of the deposit is established. Depth analysis is taken for the relationship between the braided river sand body and base level cycles. And the position, distribution, and genesis in vertical of the braided river sand body are discussed in detail. Ore body is mainly hosted in edge of braided bar sand body, which formed in the low accommodation space, and braided channel and the braided bar interchange. So uranium enriched in the mid-term base level cycle MSC2-MSC5 in the study area. (authors)

Distribution, source identification, and ecological risk assessment of heavy metals in wetland soils of a river-reservoir system.

Science.gov (United States)

Jiang, Xiaoliang; Xiong, Ziqian; Liu, Hui; Liu, Guihua; Liu, Wenzhi

2017-01-01

The majority of rivers in the world have been dammed, and over 45,000 large reservoirs have been constructed for multiple purposes. Riparian and reservoir shorelines are the two most important wetland types in a dammed river. To date, few studies have concerned the heavy metal pollution in wetland soils of these river-reservoir systems. In this study, we measured the concentrations of ten heavy metals (Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, and Zn) in surface soils collected from riparian and reservoir shorelines along the Han River in different seasons. Our results found that the Co, Cu, and Ni concentrations in riparian wetlands were significantly lower than those in reservoir shorelines. In riparian wetlands, only soil Sr concentration significantly increased after summer and autumn submergence. Multivariate statistical analyses demonstrated that Ba and Cd might originate from industrial and mining sources, whereas Sr and Mn predominantly originated from natural rock weathering. The ecological risk assessment analysis indicated that both riparian and reservoir shorelines along the Han River in China exhibited a moderate ecological risk in soil heavy metals. The upper Han River basin is the water resource area of China's Middle Route of the South-to-North Water Transfer Project. Therefore, to control the contamination of heavy metals in wetland soils, more efforts should be focused on reducing the discharge of mining and industrial pollutants into the riparian and reservoir shorelines.

Lower Columbia River and Estuary Habitat Monitoring Study, 2011 - Final Report

Energy Technology Data Exchange (ETDEWEB)

Borde, Amy B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kaufmann, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cullinan, Valerie I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Zimmerman, Shon A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Thom, Ronald M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wright, Cynthia L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2012-03-01

The Ecosystem Monitoring Program is a collaborative effort between the Lower Columbia River Estuary Partnership (LCREP), University of Washington, Wetland Ecosystem Team (UW), US Geological Survey, Water Science Center (USGS), National Oceanic and Atmospheric Administration, National Marine Fisheries Service (NOAA-Fisheries, hereafter NOAA), and Pacific Northwest National Laboratory, Marine Sciences Laboratory (PNNL). The goal of the program is to conduct emergent wetland monitoring aimed at characterizing salmonid habitats in the lower Columbia River and estuary (LCRE) from the mouth of the estuary to Bonneville Dam (Figure 1). This is an ecosystem based monitoring program focused on evaluating status and trends in habitat and reducing uncertainties regarding these ecosystems to ultimately improve the survival of juvenile salmonids through the LCRE. This project comprehensively assesses habitat, fish, food web, and abiotic conditions in the lower river, focusing on shallow water and vegetated habitats used by juvenile salmonids for feeding, rearing and refugia. The information is intended to be used to guide management actions associated with species recovery, particularly that of threatened and endangered salmonids. PNNL’s role in this multi-year study is to monitor the habitat structure (e.g., vegetation, topography, channel morphology, and sediment type) as well as hydrologic patterns.

Patterns of Bacterial and Archaeal Gene Expression through the Lower Amazon River

Directory of Open Access Journals (Sweden)

Brandon M. Satinsky

2017-08-01

Full Text Available Analysis of metatranscriptomic and metagenomic datasets from the lower reaches of the Amazon River between Óbidos and the river mouth revealed microbial transcript and gene pools dominated by Actinobacteria, Thaumarchaeota, Bacteroidetes, Acidobacteria, Betaproteobacteria, and Planctomycetes. Three mainstem stations spanning a 625 km reach had similar gene expression patterns (transcripts gene copy−1 across a diverse suite of element cycling genes, but two tributary-influenced stations at the mouth of the Tapajós River and near the Tocantins River at Belém had distinct transcriptome composition and expression ratios, particularly for genes encoding light-related energy capture (higher and iron acquisition and ammonia oxidation (lower. Environmental parameters that were useful predictors of gene expression ratios included concentrations of lignin phenols, suspended sediments, nitrate, phosphate, and particulate organic carbon and nitrogen. Similar to the gene expression data, these chemical properties reflected highly homogeneous mainstem stations punctuated by distinct tributary-influenced stations at Tapajós and Belém. Although heterotrophic processes were expected to dominate in the lower Amazon, transcripts from photosynthetic bacteria were abundant in tributary-influenced regions, and transcripts from Thaumarcheota taxa genetically capable of chemosynthetic ammonia oxidation accounted for up to 21% of the transcriptome at others. Based on regressions of transcript numbers against gene numbers, expression ratios of Thaumarchaeota populations were largely unchanged within the mainstem, suggesting a relatively minor role for gene regulation. These quantitative gene and transcript inventories detail a diverse array of energy acquisition strategies and metabolic capabilities for bacteria and archaea populations of the world's largest river system.

Patterns of Bacterial and Archaeal Gene Expression through the Lower Amazon River

Energy Technology Data Exchange (ETDEWEB)

Satinsky, Brandon M.; Smith, Christa B.; Sharma, Shalabh; Ward, Nicholas D.; Krusche, Alex V.; Richey, Jeffrey E.; Yager, Patricia L.; Crump, Byron C.; Moran, Mary Ann

2017-08-08

Analysis of metatranscriptomic and metagenomic datasets from the lower reaches of the Amazon River between Obidos and the river mouth revealed microbial transcript and gene pools dominated by Actinobacteria, Thaumarchaeota, Bacteroidetes, Acidobacteria, Betaproteobacteria, and Planctomycetes. Three mainstem stations spanning a 625 km reach had similar gene expression patterns (transcripts gene copy-1) across a diverse suite of element cycling genes, but two tributary-influenced stations at the mouth of the Tapajos River and near the Tocantins River at Belem had distinct transcriptome composition and expression ratios, particularly for genes encoding light-related energy capture (higher) and iron acquisition and ammonia oxidation (lower). Environmental parameters that were useful predictors of gene expression ratios included concentrations of lignin phenols, suspended sediments, nitrate, phosphate, and particulate organic carbon and nitrogen. Similar to the gene expression data, these chemical properties reflected highly homogeneous mainstem stations punctuated by distinct tributary- influenced stations at Tapajos and Belem. Although heterotrophic processes were expected to dominate in the lower Amazon, transcripts from photosynthetic bacteria were abundant in tributary-influenced regions, and transcripts from Thaumarcheota taxa genetically capable of chemosynthetic ammonia oxidation accounted for up to 21% of the transcriptome at others. Based on regressions of transcript numbers against gene numbers, expression ratios of Thaumarchaeota populations were largely unchanged within the mainstem, suggesting a relatively minor role for gene regulation. These quantitative gene and transcript inventories detail a diverse array of energy acquisition strategies and metabolic capabilities for bacteria and archaea populations of the world’s largest river system.

Contaminants of emerging concern in the lower Stillaguamish River Basin, Washington, 2008-11

Science.gov (United States)

Wagner, Richard J.; Moran, Patrick W.; Zaugg, Steven D.; Sevigny, Jennifer M.; Pope, Judy M.

2014-01-01

A series of discrete water-quality samples were collected in the lower Stillaguamish River Basin near the city of Arlington, Washington, through a partnership with the Stillaguamish Tribe of Indians. These samples included surface waters of the Stillaguamish River, adjacent tributary streams, and paired inflow and outflow sampling at three wastewater treatment plants in the lower river basin. Chemical analysis of these samples focused on chemicals of emerging concern, including wastewater compounds, human-health pharmaceuticals, steroidal hormones, and halogenated organic compounds on solids and sediment. This report presents the methods used and data results from the chemical analysis of these samples

Rethinking avian response to Tamarix on the lower Colorado River: A threshold hypothesis

Science.gov (United States)

van Riper, Charles; Paxton, K.L.; O'brien, C.; Shafroth, P.B.; McGrath, L.J.

2008-01-01

Many of the world's large river systems have been greatly altered in the past century due to river regulation, agriculture, and invasion of introduced Tamarix spp. (saltcedar, tamarisk). These riverine ecosystems are known to provide important habitat for avian communities, but information on responses of birds to differing levels of Tamarix is not known. Past research on birds along the Colorado River has shown that avian abundance in general is greater in native than in non-native habitat. In this article, we address habitat restoration on the lower Colorado River by comparing abundance and diversity of avian communities at a matrix of different amounts of native and non-native habitats at National Wildlife Refuges in Arizona. Two major patterns emerged from this study: (1) Not all bird species responded to Tamarix in a similar fashion, and for many bird species, abundance was highest at intermediate Tamarix levels (40-60%), suggesting a response threshold. (2) In Tamarix-dominated habitats, the greatest increase in bird abundance occurred when small amounts of native vegetation were present as a component of that habitat. In fact, Tamarix was the best vegetation predictor of avian abundance when compared to vegetation density and canopy cover. Our results suggest that to positively benefit avian abundance and diversity, one cost-effective way to rehabilitate larger monoculture Tamarix stands would be to add relatively low levels of native vegetation (???20-40%) within homogenous Tamarix habitat. In addition, this could be much more cost effective and feasible than attempting to replace all Tamarix with native vegetation. ?? 2008 Society for Ecological Restoration International.

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Summary

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four -lower Snake- Rive salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Hans Jürman 85 : Hans Jürman: kes ma olen? / Hans Jürman

Index Scriptorium Estoniae

Jürman, Hans, 1923-2014

2010-01-01

Hans Jürmani lapsepõlvest, kooliaastatest ning ülikooliajast. Olles hariduselt eesti filoloog on Hans Jürman töötanud ka apteekrina ja õpetajana, kuid suurema osa oma elust raamatukogudes, põhiliselt Tallinna Keskraamatukogus ja Eesti NSV Riiklikus Avalikus Raamatukogus, viimasel ajal tegeleb terminoloogiaga

Riverbank Collapse on the lower Murray River: recent phenomenon or long-term geomorphic process?

Science.gov (United States)

De Carli, E.; Hubble, T.; Jaksa, M.; Clarke, S. L.; Airey, D.; O'Toole, J.; Carpenter, G.

2013-12-01

The lower Murray River connects the Murray-Darling River Basin to the Southern Ocean and drains 14% of Australia's landmass. During the Millennium Drought (1997-2011) record low inflows for the Basin were recorded and the lower Murray River received only 19% of its long-term average inflow for 2008-2009, causing the pool-level in the lowermost reaches near Goolwa to fall 1 m below sea level. This event triggered widespread mass failure in the alluvial river banks and ground subsidence in some river-adjacent floodplain deposits between Blanchetown and Lake Alexandrina. Multi-beam bathymetry, sediment core and geotechnical data are presented for a number of sites investigated between Mannum and White Sands. Interpretation of this data indicates three different bank-failure slide morphologies present in the banks and adjacent channel. Type 1, ';recent' (2009-2011) deep-seated rotational slumps characterised by distinct, sharply-defined failure scars and associated debris fields of angular blocks shed from the failure site. Type 2, ';relatively-recent' shallow planar-failures, with less well-defined smoother failure scars and associated debris fields of smoothed or rounded blocks and pinnacles. Type 3, ';relatively-old' shallow planar-failures characterised by subdued relief slump scars that do not present an associated debris field. It is suspected that successive floods or high-flow events progressively erode and redistribute material, smoothing the landslide scars and redistributing the slide-debris deposits. Bank-failure and the delivery of material from the slides into the channel is interpreted as an ongoing and long-term geomorphic characteristic of the lower Murray River, rather than a new phenomenon that occurred as a response to unusually low river levels during the Millennium Drought. The larger size and rotational style of the recent Type 1 failures is most likely to be a consequence of the drought and anthropogenic modifications of the river channel and

Population data of 17 short tandem repeat loci in 2923 individuals from the Han population of Nantong in East China.

Science.gov (United States)

Yang, Min; Li, Liming; Han, Haijun; Jin, Li; Jia, Dongtao; Li, Shilin

2016-09-01

Nantong is located in mid-eastern China, and the Han population in Nantong may be greatly affected by population admixture between northern and southern Han Chinese populations. In this study, we analyzed 17 autosomal short tandem repeat (STR) loci on 2923 unrelated individuals collected from the Han population of Nantong. No significant deviation from Hardy-Weinberg equilibrium was observed at all STR loci, and the expected heterozygosity ranged from 0.6184 to 0.9187. The combined match probability (CMP) was 3.87 × 10(-21), and the combined power of discrimination (CPD) was 99.999999999999999999613 %. No significant difference of allele frequencies was observed between Nantong and other Han populations at all STR loci, as well as Dai, Mongolian, and Tibetan. Significant differences were only observed between Nantong Han and Uyghur at TH01, as well as Nantong Han and Dong at CSF1PO and FGA. Nantong Han showed significant differences between She, Bouyei, and Miao at multiple STR loci.

Sediment accumulation owing to backwater effect in the lower reach of the Stung Sen River, Cambodia

Science.gov (United States)

Nagumo, Naoko; Kubo, Sumiko; Sugai, Toshihiko; Egashira, Shinji

2017-11-01

We examined channel bars at two sites in the lower reach of the Stung Sen River, which flows into Lake Tonle Sap, Cambodia, to identify sediment transport and accumulation processes during monsoon-related flood events and to investigate how sediment transport capacity changes as a result of enhanced backwater effect of the lake. Channel bars in the lower reach of the Stung Sen River that emerge in the dry season were classified into type A (lateral bars), type B (point bars), type C (concave-bank benches) and type D (diagonal and island bars, or fluvial dunes) based on Nagumo et al.'s previous study. Type B, type C, and type D channel bars were at our study sites of SEN-01 and SEN-02, about 83 and 77 km from the river mouth respectively. Computation of water surface profiles showed that sediment transport capacity of the Stung Sen River decreased abruptly after the peak flow stage because of the backwater effect from Lake Tonle Sap during the decreasing flow stage. Our observations suggest that alternating layers of sand and silt to clay layers accumulate to form type C channel bars, corresponding to changes in sediment transport capacity controlled by backwater effects from Lake Tonle Sap and by changes in flow depths and associated slackwater systems. The accumulation of alternating silt and sand layers of type B channel bars results from lateral sediment transportation that is accelerated with an increase of secondary flow, whereas development of type D channel bars is related to bedload mobility.

Population trends, bend use relative to available habitat and within-river-bend habitat use of eight indicator species of Missouri and Lower Kansas River benthic fishes: 15 years after baseline assessment

Science.gov (United States)

Wildhaber, Mark L.; Yang, Wen-Hsi; Arab, Ali

2016-01-01

A baseline assessment of the Missouri River fish community and species-specific habitat use patterns conducted from 1996 to 1998 provided the first comprehensive analysis of Missouri River benthic fish population trends and habitat use in the Missouri and Lower Yellowstone rivers, exclusive of reservoirs, and provided the foundation for the present Pallid Sturgeon Population Assessment Program (PSPAP). Data used in such studies are frequently zero inflated. To address this issue, the zero-inflated Poisson (ZIP) model was applied. This follow-up study is based on PSPAP data collected up to 15 years later along with new understanding of how habitat characteristics among and within bends affect habitat use of fish species targeted by PSPAP, including pallid sturgeon. This work demonstrated that a large-scale, large-river, PSPAP-type monitoring program can be an effective tool for assessing population trends and habitat usage of large-river fish species. Using multiple gears, PSPAP was effective in monitoring shovelnose and pallid sturgeons, sicklefin, shoal and sturgeon chubs, sand shiner, blue sucker and sauger. For all species, the relationship between environmental variables and relative abundance differed, somewhat, among river segments suggesting the importance of the overall conditions of Upper and Middle Missouri River and Lower Missouri and Kansas rivers on the habitat usage patterns exhibited. Shoal and sicklefin chubs exhibited many similar habitat usage patterns; blue sucker and shovelnose sturgeon also shared similar responses. For pallid sturgeon, the primary focus of PSPAP, relative abundance tended to increase in Upper and Middle Missouri River paralleling stocking efforts, whereas no evidence of an increasing relative abundance was found in the Lower Missouri River despite stocking.

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Part II: Chapters 5-13

National Research Council Canada - National Science Library

2003-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Environmental isotope-aided studies on river water and groundwater interaction in the region of Seoul and Taegu

International Nuclear Information System (INIS)

Jong Sung Ahn

1988-01-01

Environmental isotope-aided studies on river water and groundwater interaction in the Han River Basin in areas especially occupied by crystalline rocks and limestone have been undertaken. The result indicates that the groundwater in the Seoul area is recharged by the Han River whereas in non-urban areas it is replenished by the infiltration of precipitation, the crystalline rock aquifers are recharged by downward percolation of shallow groundwater stored in overlying alluvium. Older groundwater having a very low concentration of tritium, ranging from 0 to 2 TU, was observed at the lower Han River basin near Bupyeong. It may indicate that the water sampled was recharged at a much earlier time than the other groundwater sampled, maybe, as early as the pre-thermonuclear period. The same interaction study conducted in the Karst area has shown that there is clearly no systematic differences of tritium level between surface water and groundwater and that the residence time of groundwater in limestone is very short, probably not longer than a few months. The areas recharged by the water from the overlying alluvium into the sedimentary rock aquifer were restricted only along the Kumho River channel and its tributaries in a clastic sedimentary rock area. Bedrock groundwater whose tritium level and stable isotope composition were less than 14 TU and -6.8 respectively was observed in the central part of Taegu city. (author). 15 refs, 21 figs, 8 tabs

Ground-water resources in the tri-state region adjacent to the Lower Delaware River

Science.gov (United States)

Barksdale, Henry C.; Greenman, David W.; Lang, Solomon Max; Hilton, George Stockbridge; Outlaw, Donald E.

1958-01-01

The purpose of this report is to appraise and evaluate the groundwater resources of a tri-state region adjacent to the lower Delaware River that is centered around Philadelphia, Pa., and Camden, N. J., and includes Wilmington, Del., and Trenton, N.J. Specifically, the region includes New Castle County, Del.; Burlington, Camden, Gloucester, Mercer, and Salem Counties in New Jersey; and Bucks, Chester, Delaware, Montgomery, and Philadelphia Counties in Pennsylvania.

Life-history variability of non-native centrarchids in regulated river systems of the lower River Guadiana drainage (south-west Iberian Peninsula).

Science.gov (United States)

Ribeiro, F; Collares-Pereira, M J

2010-02-01

Life-history variability of two non-native centrarchids, pumpkinseed Lepomis gibbosus and largemouth bass Micropterus salmoides, was evaluated in three stream stretches of the lower River Guadiana drainage (south-west Iberian Peninsula) with different degrees of regulated flows. Abundance, condition and population structure differed among populations for both species, but invasion success was lower in the least regulated river. Lepomis gibbosus were abundant and had multiple age classes in the three river sites, whereas M. salmoides were less abundant and mainly represented by young-of-the-year fish. Juvenile growth in L. gibbosus was similar in all three populations, though longevity was slightly greater in the population from the River Guadiana mainstream. Lepomis gibbosus exhibited a long reproductive season, but the duration of season, size at maturity and reproductive effort varied among populations. The life-history differences found demonstrate the importance of species adaptation to local conditions which might favour their invasion success. Lepomis gibbosus were more adaptable and resilient to local conditions, whereas M. salmoides seemed dependent on reservoirs and large rivers for maintenance of riverine populations.

Impacts of reforestation upon sediment load and water outflow in the Lower Yazoo River Watershed, Mississippi

Science.gov (United States)

Ying Ouyang; Theodor D. Leininger; Matt Moran

2013-01-01

Among the world’s largest coastal and river basins, the Lower Mississippi River Alluvial Valley (LMRAV)is one of the most disturbed by human activities. This study ascertained the impacts of reforestation on water outflow attenuation (i.e., water flow out of the watershed outlet) and sediment load reduction in the Lower Yazoo River Watershed (LYRW) within the LMRAV...

Synthetic organic agrochemicals in the lower Mississippi River and its major tributaries: Distribution, transport and fate

Science.gov (United States)

Pereira, W.E.; Rostad, C.E.; Leiker, T.J.; ,

1992-01-01

The Mississippi River and its major tributaries transport herbicides and their degradation products from agricultural areas in the mid-western U.S.A. These compounds include atrazine and its degradation products (desethyl- and desisopropylatrazine), simazine, cyanazine, metolachlor, and alachlor and its degradation products (2-chloro-2',6'-diethylacetanilide, 2-hydroxy-2',6'-diethylacetanilide and 2,6-diethylaniline). These compounds were identified and confirmed by gas chromatography-ion trap mass spectrometry. Loads of these compounds were determined during five sampling trips in 1987-1989. Stream loads of these compounds indicated that atrazine and metolachlor were relatively conservative in downstream transport. Alachlor and its degradation products were generated from point and non-point sources. Seasonal variations and hydrologic conditions controlled the loads of these compounds in the Mississippi River. Cross-channel mixing was slow downstream from major river confluences, possibly requiring several hundred kilometers of downriver transit for completion. The annual transport of these compounds into the Gulf of Mexico was estimated to be < 2% of the annual application of each herbicide in the Midwest.The Mississippi River and its major tributaries transport herbicides and their degradation products from agricultural areas in the mid-western U.S.A. These compounds include atrazine and its degradation products (desethyl- and desisopropylatrazine), simazine, cyanazine, metolachlor, and alachlor and its degradation products (2-chloro-2???,6???-diethylacetanilide, 2-hydroxy-2???,6???-diethylacetanilide and 2,6-diethylaniline). These compounds were identified and confirmed by gas chromatography-ion trap mass spectrometry. Loads of these compounds were determined during five sampling trips in 1987-1989. Stream loads of these compounds indicated that atrazine and metolachlor were relatively conservative in downstream transport. Alachlor and its degradation products

Improvements in Hudson River Water Quality Create the Need for a new Approach to Monitoring and Management

Science.gov (United States)

O'Mullan, G. D.; Juhl, A.; Sambrotto, R.; Lipscomb, J.; Brown, T.

2008-12-01

The lower Hudson River is a well-flushed temperate estuary that continues to support diverse wildlife populations although its shores are home to the nation's most populated metropolitan area. Data sets from the last hundred years clearly demonstrate extreme nutrient concentrations, pathogen loading, and periods of persistent hypoxia. These data also show a clear trend of steadily improving water quality in the last thirty years. Recent increases in recreational activity, expanded shoreline parks, and waterfront redevelopment, indicate the return of the people of New York to the River, concomitant with improved water quality. While mean seasonal water quality indicators are now often acceptable for large portions of the River, there remains a lack of information about the finer scale spatial and temporal variability of water quality. A new water quality sampling program was initiated in the Fall of 2006 to address this challenge. Monthly sampling cruises collected continuous underway surface measurements of hydrographic variables in parallel with discrete sampling for nutrients and microbiology. In general, these data indicate that mid-channel locations are often within acceptable water quality standards during dry weather, but that wet weather events deliver large quantities of sewage to the River, leading to short-term deterioration in water quality. In 2006-2007, only 6 of 27 sample sites had geometric mean values for Enterococcus , a sewage-indicating microorganism, that suggest consistently poor water quality. In contrast, single-day exceedances of EPA recommended guidelines for Enterococcus were found at 21 of the 27 sites. Although the mid-channel of the River was relatively homogenous with respect to sewage indicators, large changes were observed at tributary mixing interfaces and along the shallow edges of the River where human contact is most likely. The changing use of the River, together with new information about the importance of episodic and

Longitudinal patterns of fish assemblages, aquatic habitat, and water temperature in the Lower Crooked River, Oregon

Science.gov (United States)

Torgersen, Christian E.; Hockman-Wert, David P.; Bateman, Douglas S.; Leer, David W.; Gresswell, Robert E.

2007-01-01

The Lower Crooked River is a remarkable groundwater-fed stream flowing through vertical basalt canyons in the Deschutes River Valley ecoregion in central Oregon (Pater and others, 1998). The 9-mile section of the river between the Crooked River National Grasslands boundary near Ogden Wayside and river mile (RM) 8 is protected under the National Wild and Scenic Rivers Act (16 U.S.C. 1271-1287) for its outstandingly remarkable scenic, recreational, geologic, hydrologic, wildlife, and botanical values (ORVs), and significant fishery and cultural values. Groundwater springs flow directly out of the canyon walls into the Lower Crooked River and create a unique hydrologic setting for native coldwater fish, such as inland Columbia Basin redband trout (Oncorhynchus mykiss gairdneri). To protect and enhance the ORVs that are the basis for the wild and scenic designation, the Bureau of Land Management (BLM) has identified the need to evaluate, among other conditions, fish presence and habitat use of the Lower Crooked River. The results of this and other studies will provide a scientific basis for communication and cooperation between the BLM, Oregon Water Resources Department, Oregon Department of Fish and Wildlife (ODFW) and all water users within the basin. These biological studies initiated by the BLM in the region reflect a growing national awareness of the impacts of agricultural and municipal water use on the integrity of freshwater ecosystems.

Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2001-2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Hillson, Todd D. (Washington Department of Wildlife, Olympia, WA)

2002-10-01

The National Marine Fisheries Service (NMFS) listed Lower Columbia River chum as threatened under the auspices of the Endangered Species Act (ESA) in March of 1999 (64 FR 14508, March 25, 1999). The listing was in response to reduction in abundance from historical levels of more than half a million returning adults to fewer than 10,000 spawners present day (Johnson et al. 1997). Harvest, loss of habitat, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for the decline in this species in the Columbia River. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of chum salmon (Johnson et al. 1997). This is especially true of the population located directly below Bonneville Dam where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. The recovery strategy for Lower Columbia River chum as outlined in the Hatchery Genetic Management Plan (HGMP) for the Grays River project has four main tasks. First, determine if remnant populations of Lower Columbia River chum salmon exist in Lower Columbia River tributaries. Second, if such populations exist, develop stock-specific recovery plans that would involve habitat restoration including the creation of spawning refugias, supplementation if necessary and a habitat and fish monitoring and evaluation plan. If chum have been extirpated from previously utilized streams, develop re-introduction plans that utilize appropriate genetic donor stock(s) of Lower Columbia River chum salmon and integrate habitat improvement and fry-to-adult survival evaluations. Third, reduce the extinction risk to Grays River chum salmon population by randomly capturing adults in the basin for use in a supplementation program and reintroduction of Lower Columbia River chum salmon into the Chinook River basin. The

Timing, frequency and environmental conditions associated with mainstem-tributary movement by a lowland river fish, golden perch (Macquaria ambigua.

Directory of Open Access Journals (Sweden)

Wayne M Koster

Full Text Available Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007-2011. Fish were tagged and released in autumn 2007-2009 in the mid-Murray (n = 42 and lower Goulburn (n = 37 rivers within 3-6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem-tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem-tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers.

Timing, frequency and environmental conditions associated with mainstem-tributary movement by a lowland river fish, golden perch (Macquaria ambigua).

Science.gov (United States)

Koster, Wayne M; Dawson, David R; O'Mahony, Damien J; Moloney, Paul D; Crook, David A

2014-01-01

Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua) between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007-2011). Fish were tagged and released in autumn 2007-2009 in the mid-Murray (n = 42) and lower Goulburn (n = 37) rivers within 3-6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem-tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem-tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers.

Timing, Frequency and Environmental Conditions Associated with Mainstem–Tributary Movement by a Lowland River Fish, Golden Perch (Macquaria ambigua)

Science.gov (United States)

Koster, Wayne M.; Dawson, David R.; O’Mahony, Damien J.; Moloney, Paul D.; Crook, David A.

2014-01-01

Tributary and mainstem connections represent important links for the movement of fish and other biota throughout river networks. We investigated the timing, frequency and environmental conditions associated with movements by adult golden perch (Macquaria ambigua) between the mainstem of the mid-Murray River and a tributary, the Goulburn River, in south-eastern Australia, using acoustic telemetry over four years (2007–2011). Fish were tagged and released in autumn 2007–2009 in the mid-Murray (n = 42) and lower Goulburn (n = 37) rivers within 3–6 km of the mid-Murray-lower Goulburn junction. 38% of tagged fish undertook mainstem–tributary movements, characterised mostly by temporary occupation followed by return of fish to the original capture river. Approximately 10% of tagged fish exhibited longer-term shifts between the mainstem and tributary. Movement of fish from the tributary into the mainstem occurred primarily during the spawning season and in some years coincided with the presence of golden perch eggs/larvae in drift samples in the mainstem. Many of the tributary-to-mainstem movements occurred during or soon after changes in flow. The movements of fish from the mainstem into the tributary were irregular and did not appear to be associated with spawning. The findings show that golden perch moved freely across the mainstem–tributary interface. This demonstrates the need to consider the spatial, behavioural and demographic interdependencies of aquatic fauna across geographic management units such as rivers. PMID:24788137

Development of HAN-based Liquid Propellant Thruster

Science.gov (United States)

Hisatsune, K.; Izumi, J.; Tsutaya, H.; Furukawa, K.

2004-10-01

Many of propellants that are applied to the conventional spacecraft propulsion system are toxic propellants. Because of its toxicity, considering the environmental pollution or safety on handling, it will be necessary to apply the "green" propellant to the spacecraft propulsion system. The purpose of this study is to apply HAN based liquid propellant (LP1846) to mono propellant thruster. Compared to the hydrazine that is used in conventional mono propellant thruster, HAN based propellant is not only lower toxic but also can obtain higher specific impulse. Moreover, HAN based propellant can be decomposed by the catalyst. It means there are the possibility of applying to the mono propellant thruster that can leads to the high reliability of the propulsion system.[1],[2] However, there are two technical subjects, to apply HAN based propellant to the mono propellant thruster. One is the high combustion temperature. The catalyst will be damaged under high temperature condition. The other is the low catalytic activity. It is the serious problem on application of HAN based propellant to the mono propellant thruster that is used for attitude control of spacecraft. To improve the catalytic activity of HAN based propellant, it is necessary to screen the best catalyst for HAN based propellant. The adsorption analysis is conducted by Monte Carlo Simulation to screen the catalyst metal for HAN and TEAN. The result of analysis shows the Iridium is the best catalyst metal for HAN and TEAN. Iridium is the catalyst metal that is used at conventional mono propellant thruster catalyst Shell405. Then, to confirm the result of analysis, the reaction test about catalyst is conducted. The result of this test is the same as the result of adsorption analysis. That means the adsorption analysis is effective in screening the catalyst metal. At the evaluating test, the various types of carrier of catalyst are also compared to Shell 405 to improve catalytic activity. The test result shows the

76 FR 13422 - Lower Mississippi River Waterway Safety Advisory Committee; Vacancies

Science.gov (United States)

2011-03-11

... the Lower Mississippi River and its connecting navigable waterways, including the Gulf of Mexico. The... receive no salary, reimbursement of travel expenses, or other compensation from the Federal Government...

ECTOPARASITIC TREMATODES ON Scardinius erythrophthalmus FROM THE LOWER FLOW OF THE SAVA RIVER

Directory of Open Access Journals (Sweden)

Zlatko Nedić

2014-12-01

Full Text Available The research on ectoparasitic trematodes on Scardinius erythrophthalmus from the lower flow of the Sava River showed three species of trematodes, which parasitized on the fish gills and fish skin. During the study period, we sampled 120 individuals of Scardinius erythrophthalmus. In total, 85 individuals or more than 70% showed the presence of one of the three types of ectoparasitic trematodes. Determination of the trematodes was done to the species level for one species (Posthodiplosomum cuticola and to the genus level for two of them (Dactylogyrus and Gyrodactylus. Key words: Sava River, lower flow, Orašje, ectoparasitictrematodes

Channel change and bed-material transport in the Lower Chetco River, Oregon

Science.gov (United States)

Wallick, J. Rose; Anderson, Scott W.; Cannon, Charles; O'Connor, Jim E.

2010-01-01

The lower Chetco River is a wandering gravel-bed river flanked by abundant and large gravel bars formed of coarse bed-material sediment. Since the early twentieth century, the large gravel bars have been a source of commercial aggregate for which ongoing permitting and aquatic habitat concerns have motivated this assessment of historical channel change and sediment transport rates. Analysis of historical channel change and bed-material transport rates for the lower 18 kilometers shows that the upper reaches of the study area are primarily transport zones, with bar positions fixed by valley geometry and active bars mainly providing transient storage of bed material. Downstream reaches, especially near the confluence of the North Fork Chetco River, are zones of active sedimentation and channel migration.Multiple analyses, supported by direct measurements of bedload during winter 2008–09, indicate that since 1970 the mean annual flux of bed material into the study reach has been about 40,000–100,000 cubic meters per year. Downstream tributary input of bed-material sediment, probably averaging 5–30 percent of the influx coming into the study reach from upstream, is approximately balanced by bed-material attrition by abrasion. Probably little bed material leaves the lower river under natural conditions, with most net influx historically accumulating in wider and more dynamic reaches, especially near the North Fork Chetco River confluence, 8 kilometers upstream from the Pacific Ocean.The year-to-year flux, however, varies tremendously. Some years may have less than 3,000 cubic meters of bed material entering the study area; by contrast, some high-flow years, such as 1982 and 1997, likely have more than 150,000 cubic meters entering the reach. For comparison, the estimated annual volume of gravel extracted from the lower Chetco River for commercial aggregate during 2000–2008 has ranged from 32,000 to 90,000 cubic meters and averaged about 59,000 cubic meters per

Homage to Professor Hans-Åke Gustafsson

CERN Multimedia

2010-01-01

It was with deep sadness that we learned of the death of Professor Hans-Åke Gustafsson, an internationally recognized scientist, beloved colleague and friend. He passed away on Wednesday January 13th at the Lund University Hospital, surrounded by his loved ones, after a short battle against cancer. This is a great loss for all of us in ALICE and the whole heavy ion community. Hans-Åke, Professor at Lund University, was one of the pioneers of heavy ion physics with relativistic beams since its very beginning. He started his research at CERN, as a fellow at the ISOLDE ion beam facility, and immediately after, in the early 1980 joined the Plastic Ball collaboration at the Bevalac. One of the seminal papers of the field on the discovery of collective flow in relativistic nuclear collisions, co-authored by Hans-Åke, Hans Gutbrod and colleagues, stems from this period. From that point on he was always at the forefront of research with relativistic nuclear beams, being for three de...

Reintroduction of Lower Columbia River Chum Salmon into Duncan Creek, 2007 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Hillson, Todd D. [Washington Department of Fish and Wildlife

2009-06-12

The National Marine Fisheries Service (NMFS) listed Lower Columbia River (LCR) chum salmon as threatened under the Endangered Species Act (ESA) in March, 1999 (64 FR 14508, March 25, 1999). The listing was in response to the reduction in abundance from historical levels of more than one-half million returning adults to fewer than 10,000 present-day spawners. Harvest, habitat degradation, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for this decline. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of this species. This is especially true of the population located directly below Bonneville Dam, where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. Prior to 1997, only two chum salmon populations were recognized as genetically distinct in the Columbia River, although spawning had been documented in many Lower Columbia River tributaries. The first population was in the Grays River (RKm 34), a tributary of the Columbia River, and the second was a group of spawners utilizing the mainstem Columbia River just below Bonneville Dam (RKm 235) adjacent to Ives Island and in Hardy and Hamilton creeks. Using additional DNA samples, Small et al. (2006) grouped chum salmon spawning in the mainstem Columbia River and the Washington State tributaries into three groups: the Coastal, the Cascade and the Gorge. The Coastal group comprises those spawning in the Grays River, Skamokawa Creek and the broodstock used at the Sea Resources facility on the Chinook River. The Cascade group comprises those spawning in the Cowlitz (both summer and fall stocks), Kalama, Lewis, and East Fork Lewis rivers, with most supporting unique populations. The Gorge group comprises those spawning in the mainstem Columbia River from the I-205 Bridge up to

BIOLOGICAL CHARACTERISTICS OF PIKE (ESOX LUCIUS LINNAEUS, 1758 OF THE LOWER DNIEPER RIVER IN CURRENT CONDITIONS

Directory of Open Access Journals (Sweden)

K. Geina

2015-03-01

Full Text Available Purpose. To analyze major biological characteristics of pike (Esox lucius L., 1758 stock in the lower Dnieper River in the conditions of transformed flow. Methodology. Collection of the ichthyological material was carried out in the lower Dnieper River from commercial fishing gears, including beach seines, drag seines, fyke-nets. Field, laboratory processing of samples and mathematical analysis of the obtained results were carried out according to generally accepted methods and guidelines with some assumptions regarding the duration of pike fattening directly in the lower Dnieper River. Findings. Recent years, there is an increase in the specific weight of younger age groups in the pike stock in the lower Dnieper River. Analysis of linear growth indicates on satisfactory environmental conditions for pike. Current commercial contingent of pike is based on size classes of 46–50 cm versus 22–32 cm in the first half of the last century. Reproductive properties of pike, in particular fecundity, egg size and maturity coefficients did not virtually change compared to those of the last century. Depending on linear sizes, the absolute fecundity is 32.3–155.8 thousand eggs and the maturation coefficient is 11.1–15.7%. Morphologic variability of pike in the lower Dnieper River during the period from 1980s to the present time was observed for plastic features, which characterized fin sizes. Sexual dimorphism in current conditions was observed only for maximum body depth. No significant differences for other plastic features between males and females of pike in the lower Dnieper River. Originality. The data on biological characteristics of pike stock from the lower Dnieper River have been updated. Current fecundity of females of different size groups recorded in commercial catches was been determined. An analysis of morphological variability of major plastic features of pike in the process of the transformation of the Dnieper River flow has been

Declining groundwater level caused by irrigation to row crops in the Lower Mississippi River Basin, Current Situation and Trends

Science.gov (United States)

Feng, G.; Gao, F.; Ouyang, Y.

2017-12-01

The Mississippi River is North America's largest river and the second largest watershed in the world. It flows over 3,700 km through America's heartland to the Gulf of Mexico. Over 3 million hectares in the Lower Mississippi River Basin represent irrigated cropland and 90 percent of those lands currently rely on the groundwater supply. The primary crops grown in this region are soybean, corn, cotton, and rice. Increased water withdrawals for irrigating those crops and stagnant recharging jeopardize the long-term availability of the aquifer and place irrigation agriculture in the region on an unsustainable path. The objectives of this study were to: 1) analyze the current groundwater level in the Lower Mississippi River Basin based on the water table depth observed by Yazoo Mississippi Delta Joint Water Management District from 2000 and 2016; 2) determine trends of change in groundwater level under conventional and groundwater saving irrigation management practices (ET or soil moisture based full irrigation scheduling using all groundwater or different percentages of ground and surface water). The coupled SWAT and MODFLOW model was applied to investigate the trends. Observed results showed that the groundwater level has declined from 33 to 26 m at an annual decrease rate of 0.4 m in the past 17 years. Simulated results revealed that the groundwater storage was decreased by 26 cm/month due to irrigation in crop season. It is promising that the groundwater storage was increased by 23 cm/month, sometimes even 60 cm/month in crop off-growing season because of recharge from rainfall. Our results suggest that alternative ET or soil moisture based groundwater saving irrigation scheduling with conjunctive use of surface water is a sustainable practice for irrigated agriculture in in the Lower Mississippi River Basin.

Sediment transport in the lower Snake and Clearwater River Basins, Idaho and Washington, 2008–11

Science.gov (United States)

Clark, Gregory M.; Fosness, Ryan L.; Wood, Molly S.

2013-01-01

Sedimentation is an ongoing maintenance problem for reservoirs, limiting reservoir storage capacity and navigation. Because Lower Granite Reservoir in Washington is the most upstream of the four U.S. Army Corps of Engineers reservoirs on the lower Snake River, it receives and retains the largest amount of sediment. In 2008, in cooperation with the U.S. Army Corps of Engineers, the U.S. Geological Survey began a study to quantify sediment transport to Lower Granite Reservoir. Samples of suspended sediment and bedload were collected from streamgaging stations on the Snake River near Anatone, Washington, and the Clearwater River at Spalding, Idaho. Both streamgages were equipped with an acoustic Doppler velocity meter to evaluate the efficacy of acoustic backscatter for estimating suspended-sediment concentrations and transport. In 2009, sediment sampling was extended to 10 additional locations in tributary watersheds to help identify the dominant source areas for sediment delivery to Lower Granite Reservoir. Suspended-sediment samples were collected 9–15 times per year at each location to encompass a range of streamflow conditions and to capture significant hydrologic events such as peak snowmelt runoff and rain-on-snow. Bedload samples were collected at a subset of stations where the stream conditions were conducive for sampling, and when streamflow was sufficiently high for bedload transport. At most sampling locations, the concentration of suspended sediment varied by 3–5 orders of magnitude with concentrations directly correlated to streamflow. The largest median concentrations of suspended sediment (100 and 94 mg/L) were in samples collected from stations on the Palouse River at Hooper, Washington, and the Salmon River at White Bird, Idaho, respectively. The smallest median concentrations were in samples collected from the Selway River near Lowell, Idaho (11 mg/L), the Lochsa River near Lowell, Idaho (11 mg/L), the Clearwater River at Orofino, Idaho (13 mg

The Water Level and Transport Regimes of the Lower Columbia River

Science.gov (United States)

Jay, D. A.

2011-12-01

Tidal rivers are vital, spatially extensive conduits of material from land to sea. Yet the tidal-fluvial regime remains poorly understood relative to the bordering fluvial and estuarine/coastal regimes with which it interacts. The 235km-long Lower Columbia River (LCR) consists of five zones defined by topographic constrictions: a 5km-long ocean-entrance, the lower estuary (15km), an energy-minimum (67km), the tidal river (142km), and a landslide zone (5km). Buoyant plume lift-off occurs within the entrance zone, which is dominated by tidal and wave energy. The lower estuary is strongly tidally, amplifies the semidiurnal tide, and has highly variable salinity intrusion. Tidal and fluvial influences are balanced in the wide energy-minimum, into which salinity intrudes during low-flow periods. It has a turbidity maximum and a dissipation minimum at its lower end, but a water-level variance minimum at its landward end. The tidal river shows a large increase in the ratio of fluvial-to-tidal energy in the landward direction and strong seasonal variations in tidal properties. Because tidal monthly water level variations are large, low waters are higher on spring than neap tides. The steep landslide zone has only weak tides and is the site of the most seaward hydropower dam. Like many dammed systems, the LCR has pseudo-tides: daily and weakly hydropower peaking waves that propagate seaward. Tidal constituent ratios vary in the alongchannel direction due to frictional non-linearities, the changing balance of dissipation vs. propagation, and power peaking. Long-term changes to the system have occurred due to climate change and direct human manipulation. Flood control, hydropower regulation, and diversion have reduced peak flows, total load and sand transport by ~45, 50 and 80%, respectively, causing a blue-shift in the flow and water level power spectra. Overbank flows have been largely eliminated through a redundant combination of diking and flow regulation. Export of sand

Prevalence, awareness, treatment, control and risk factors related to hypertension among urban adults in Inner Mongolia 2014: differences between Mongolian and Han populations

Directory of Open Access Journals (Sweden)

Guoju Li

2016-04-01

Full Text Available Abstract Background Han and Mongolian populations constitute approximately 96 % of the population of Inner Mongolia Autonomous Region, and the two ethnic groups have different genetic backgrounds and lifestyle. We aim to assess the prevalence, awareness, treatment, control, and related risk factors of hypertension among urban adults in Inner Mongolia, with the comparison of the differences between Mongolian and Han populations in this respect. Methods Three thousand two hundred fifty-one individuals aged 20–80 years (2326 Han and 925 Mongolian were selected using a multistage cluster sampling method from Inner Mongolia in 2014. The adjusted prevalence, awareness, treatment and control of hypertension were evaluated by the Logistic regression. In addition, possible interactions were also tested. When interactions were found significant, strata-specific analysis were performed. Multivariate logistic regression was used for estimating independent associations between risk factors and hypertension. Results The prevalence of hypertension was 27.47 % for Han population, 31.46 % for Mongolian population. The adjusted prevalence, awareness, treatment and control of hypertension were 26.45, 65.43, 78.24 and 48.28 % in Han, and 31.30, 68.22, 85.57 and 50.55 % in Mongolian, respectively. There was no significant difference in the adjusted awareness, treatment and control of hypertension among Mongolian and Han adult residents (all P >0.05. Lower prevalence of hypertension was associated with younger age and healthy weight in both Mongolian and Han adults. Within Han adults, high education, moderate physical activity and non-alcohol drinkers were additionally associated with lower prevalence of hypertension, whereas within Mongolian adults, lower prevalence was associated with being female. Among residents with medium education level, nondrinkers had 0.60 times lower odds of having hypertension than current drinkers (OR = 0.60, 95 % CI: 0.44–0

Bend-scale geomorphic classification and assessment of the Lower Missouri River from Sioux City, Iowa, to the Mississippi River for application to pallid sturgeon management

Science.gov (United States)

Jacobson, Robert B.; Colvin, Michael E.; Bulliner, Edward A.; Pickard, Darcy; Elliott, Caroline M.

2018-06-07

Management actions intended to increase growth and survival of pallid sturgeon (Scaphirhynchus albus) age-0 larvae on the Lower Missouri River require a comprehensive understanding of the geomorphic habitat template of the river. The study described here had two objectives relating to where channel-reconfiguration projects should be located to optimize effectiveness. The first objective was to develop a bend-scale (that is, at the scale of individual bends, defined as “cross-over to cross-over”) geomorphic classification of the Lower Missouri River to help in the design of monitoring and evaluation of such projects. The second objective was to explore whether geomorphic variables could provide insight into varying capacities of bends to intercept drifting larvae. The bend-scale classification was based on geomorphic and engineering variables for 257 bends from Sioux City, Iowa, to the confluence with the Mississippi River near St. Louis, Missouri. We used k-means clustering to identify groupings of bends that shared the same characteristics. Separate 3-, 4-, and 6-cluster classifications were developed and mapped. The three classifications are nested in a hierarchical structure. We also explored capacities of bends to intercept larvae through evaluation of linear models that predicted persistent sand area or catch per unit effort (CPUE) of age-0 sturgeon as a function of the same geomorphic variables used in the classification. All highly ranked models that predict persistent sand area contained mean channel width and standard deviation of channel width as significant variables. Some top-ranked models also included contributions of channel sinuosity and density of navigation structures. The sand-area prediction models have r-squared values of 0.648–0.674. In contrast, the highest-ranking CPUE models have r-squared values of 0.011–0.170, indicating much more uncertainty for the biological response variable. Whereas the persistent sand model documents that

Turbidity and Total Suspended Solids on the Lower Cache River Watershed, AR.

Science.gov (United States)

Rosado-Berrios, Carlos A; Bouldin, Jennifer L

2016-06-01

The Cache River Watershed (CRW) in Arkansas is part of one of the largest remaining bottomland hardwood forests in the US. Although wetlands are known to improve water quality, the Cache River is listed as impaired due to sedimentation and turbidity. This study measured turbidity and total suspended solids (TSS) in seven sites of the lower CRW; six sites were located on the Bayou DeView tributary of the Cache River. Turbidity and TSS levels ranged from 1.21 to 896 NTU, and 0.17 to 386.33 mg/L respectively and had an increasing trend over the 3-year study. However, a decreasing trend from upstream to downstream in the Bayou DeView tributary was noted. Sediment loading calculated from high precipitation events and mean TSS values indicate that contributions from the Cache River main channel was approximately 6.6 times greater than contributions from Bayou DeView. Land use surrounding this river channel affects water quality as wetlands provide a filter for sediments in the Bayou DeView channel.

Modeling and Analysis of Sea-level Rise Impacts on Salinity in the Lower St. Johns River

Science.gov (United States)

Bacopoulos, P.

2015-12-01

There is deliberate attention being paid to studying sea-level rise impacts on the lower St. Johns River, a drowned coastal plain-type estuary with low topographic drive, located in northeastern Florida. One area of attention is salinity in the river, which influences the entire food web, including sea and marsh grasses, juvenile crustaceans and fishes, wading birds and migratory waterfowl, marine mammals and other predator animals. It is expected that elevated ocean levels will increase the salinity of the estuarine waters, leading to deleterious effects on dependent species of the river biology. The objective of the modeling and analysis was: 1) to establish baseline conditions of salinity for the lower St. Johns River; and 2) to examine future conditions of salinity, as impacted by sea-level rise. Establishing baseline conditions entailed validation of the model for present-day salinity in the lower St. Johns River via comparison to available data. Examining future conditions entailed application of the model for sea-level rise scenarios, with comparison to the baseline conditions, for evaluation of sea-level rise impacts on salinity. While the central focus was on the physics of sea-level rise impacts on salinity, some level of salinity-biological assessment was conducted to identify sea-level rise/salinity thresholds, as related to negatively impacting different species of the river biology.

Han er her endnu

DEFF Research Database (Denmark)

Bonde, Lisbeth

2012-01-01

Interview med den kinesiske aktivist og billedkunstner Ai Weiwei, der sad fængslet i 81 dage i 2011. Hans pas er stadig (i februar 2014) inddraget af myndighederne, så han kan ikke forlade landet, selv om han har betalt en bøde på 13 mio. kr. for ”skatteunddragelse”. Både i sin kunst og i sine...... mange aktioner retter han en hård kritik af det korrupte kinesiske styre, som træder menneskerettighederne under fode. Men uretfærdighedsfølelsen har sin pris i et totalitært og topstyret samfund. Ligegyldigt, hvor mange vigtige udstillinger han har i udlandet, må han blive hjemme og styre aktiviteterne...... via cyberspace. I interviewet fortæller Ai Weiwei om de personlige omkostninger, som hans kamp mod systemet indebærer....

Pb isotope evidence for contaminant-metal dispersal in an international river system: The lower Danube catchment, Eastern Europe

International Nuclear Information System (INIS)

Bird, Graham; Brewer, Paul A.; Macklin, Mark G.; Nikolova, Mariyana; Kotsev, Tsvetan; Mollov, Mihail; Swain, Catherine

2010-01-01

Lead isotope signatures ( 207 Pb/ 206 Pb, 208 Pb/ 206 Pb, 208 Pb/ 204 Pb, 206 Pb/ 204 Pb), determined by magnetic sector ICP-MS in river channel sediment, metal ores and mine waste, have been used as geochemical tracers to quantify the delivery and dispersal of sediment-associated metals in the lower Danube River catchment. Due to a diverse geology and range of ore-body ages, Pb isotope signatures in ore-bodies within the lower Danube River catchment show considerable variation, even within individual metallogenic zones. It is also possible to discriminate between the Pb isotopic signatures in mine waste and river sediment within river systems draining individual ore bodies. Lead isotopic data, along with multi-element data; were used to establish the provenance of river sediments and quantify sedimentary contributions to mining-affected tributaries and to the Danube River. Data indicate that mining-affected tributaries in Serbia and Bulgaria contribute up to 30% of the river channel sediment load of the lower Danube River. Quantifying relative sediment contributions from mining-affected tributaries enables spatial patterns in sediment-associated metal and As concentrations to be interpreted in terms of key contaminant sources. Combining geochemical survey data with that regarding the provenance of contaminated sediments can therefore be used to identify foci for remediation and environmental management strategies.

Observations on the identification of larval and juvenile Scaphirhynchus spp. in the lower Mississippi River

Science.gov (United States)

Hartfield, Paul D.; Kuntz, Nathan M.; Schramm, Harold L.

2013-01-01

Scaphirhynchus albus (Pallid Sturgeon) and S. platorynchus (Shovelnose Sturgeon) are sympatric and not uncommon in the lower Mississippi River from the confluence of the Ohio River to the Gulf of Mexico, and in its distributary, the Atchafalaya River. Reports of sturgeon larvae have been rare in the Mississippi River but have been increasing with more effective collection methods. A suite of characters identified in hatchery-reared larval Pallid Sturgeon and Shovelnose Sturgeon from the Yellowstone and upper Missouri rivers has been used to distinguish larval Scaphirhynchus spp. In the Mississippi River; however, a large proportion of wild Scaphirhynchus spp. larvae are intermediate in these characters and have been identified by some as hybridized Pallid Sturgeon and Shovelnose Sturgeon. We applied three diagnostic characters developed from Missouri River sturgeon larvae to hatchery-reared progeny of Atchafalaya River Pallid Sturgeon and found them inadequate to identify most of the known Pallid sturgeon larvae. Additionally, fewer than 10% of a large sample of wild Scaphirhynchusspp. larvae from the lower Mississippi River conformed to either Pallid Sturgeon or Shovelnose Sturgeon at two or more of the characters. We also found a small mouth width relative to head width and a concave forward barbel position may be useful for the identification of 30% or more Scaphirhynchus spp. larvae and postlarval young-of-year as Shovelnose Sturgeon. Established adult character indices and diagnostic measurement proportionalities also failed to correctly identify any hatchery-reared Pallid Sturgeon juveniles recaptured 6–7 years following their release.

How fish benefit from floodplain restoration along the lower River Rhine

NARCIS (Netherlands)

Grift, R.E.

2001-01-01

The objectives of this study were to test the beneficial value of newly created secondary channels and reconnected oxbow lakes along the lower River Rhine for fish and to give advice on position, shape and character of future water bodies. These water bodies should contribute to the

Adaptive management of flows in the lower Roanoke River, North Carolina, USA.

Science.gov (United States)

Pearsall, Sam H; McCrodden, Brian J; Townsend, Philip A

2005-04-01

The lower Roanoke River in North Carolina, USA, has been regulated by a series of dams since the 1950s. This river and its floodplain have been identified by The Nature Conservancy, the US Fish and Wildlife Service, and the State of North Carolina as critical resources for the conservation of bottomland hardwoods and other riparian and in-stream biota and communities. Upstream dams are causing extended floods in the growing season for bottomland hardwood forests, threatening their survival. A coalition of stakeholders including public agencies and private organizations is cooperating with the dam managers to establish an active adaptive management program to reduce the negative impacts of flow regulation, especially extended growing season inundation, on these conservation targets. We introduce the lower Roanoke River, describe the regulatory context for negotiating towards an active adaptive management program, present our conservation objective for bottomland hardwoods, and describe investigations in which we successfully employed a series of models to develop testable management hypotheses. We propose adaptive management strategies that we believe will enable the bottomland hardwoods to regenerate and support their associated biota and that are reasonable, flexible, and economically sustainable.

Spatial and temporal trends in PCBs in sediment along the lower Rhone River, France

Science.gov (United States)

Desmet, Marc; Mourier, Brice; Mahler, Barbara J.; Van Metre, Peter C.; Roux, Gwenaelle; Persat, Henri; Lefevre, Irene; Peretti, Annie; Chapron, Emmanuel; Anaelle, Simonneau; Miege, Cecile; Babut, Marc

2012-01-01

Despite increasingly strict control of polychlorinated biphenyl (PCB) releases in France since the mid-1970s, PCB contamination of fish recently has emerged as a major concern in the lower Rhone River basin. We measured PCB concentrations in Rhone sediment to evaluate the effects of PCB releases from major urban and industrial areas, sediment redistribution by large floods, and regulatory controls on PCB trends from 1970 to present. Profiles of PCBs (the sum of seven indicator PCB congeners) were reconstructed from sediment cores collected from an off-river rural reference site and from three depositional areas along the Rhone upstream and downstream from the city of Lyon, France. Core chronology was determined from radionuclide profiles and flood deposits. PCB concentrations increased progressively in the downstream direction, and reached a maximum concentration in 1991 of 281 μg/kg at the most downstream site. At the rural reference site and at the upstream Rhone site, PCB concentrations peaked in the 1970s (maximum concentration of 13 and 78 μg/kg, respectively) and have decreased exponentially since then. PCB concentrations in the middle and downstream cores were elevated into the early 1990s, decreased very rapidly until 2000, and since then have remained relatively stable. Congener profiles for three time windows (1965–80, 1986–93, and 2000–08) were similar in the three sediment cores from the Rhone and different from those at the rural reference site. The results indicate that permitted discharges from a hazardous-waste treatment facility upstream from Lyon might have contributed to high concentrations into the 1980-90s, but that industrial discharges from the greater Lyon area and tributaries to the Rhone near Lyon have had a greater contribution since the 1990s. There is little indication that PCB concentration in sediments downstream from Lyon will decrease over at least the short term.

Spatial distribution, temporal variability, and chemistry of the salt wedge in the lower Charles River, Massachusetts, June 1998 to July 1999

Science.gov (United States)

Breault, R.F.; Barlow, L.K.; Reisig, K.D.; Parker, G.W.

2000-01-01

The Charles River is of great recreational and ecological value to the Boston metropolitan region and the Commonwealth of Massachusetts. It is also the focus of the U.S. Environmental Protection Agency (USEPA) Region I, Clean Charles 2005 Task Force. The main goal of the Task Force is to make the Charles River 'fishable and swimmable' by the year 2005. Achieving 'fishable and swimmable' conditions will require continued progress in addressing a range of environmental conditions now degrading water quality, including the infiltration of saltwater from Boston Harbor into the freshwater Charles River.To better understand the pattern of saltwater intrusion, the U.S. Geological Survey (USGS), in cooperation with the U.S. Environmental Protection Agency (USEPA), Massachusetts Department of Environmental Management (MADEM), and New England Interstate Water Pollution Control Commission (NEIWPCC), collected data on the spatial distribution, temporal variability, and chemistry of the saltwater that entered the lower Charles River from June 1998 to July 1999. The purpose of this investigation is to extend and complement a regional-scale study of Charles River water quality conducted in 1996 (T. Faber, U.S. Environmental Protection Agency, written commun., 1997), and the ongoing water monitoring activities of the Massachusetts Water Resources Authority (MWRA) and the Charles River Watershed Association (CRWA). The data collected by this investigation supports the Clean Charles 2005 Task Force by providing detailed information concerning a major factor limiting 'fishable and swimmable' conditions in the lower Charles River. Finally, the study will be used to assist current planning efforts of the Metropolitan District Commission (MDC) to restore the historic parklands of the lower Charles River.The 'Basin' is the local term for the reach of the Charles River that begins at the Watertown Dam in Watertown, Mass., and extends about 8 mi through suburban and urban areas to Boston

A legacy of change: The lower Colorado River, Arizona-California-Nevada, USA, and Sonora-Baja California Norte, Mexico

Science.gov (United States)

Mueller, G.A.; Marsh, P.C.; Minckley, W.L.

2005-01-01

The lower Colorado is among the most regulated rivers in the world. It ranks as the fifth largest river in volume in the coterminous United States, but its flow is fully allocated and no longer reaches the sea. Lower basin reservoirs flood nearly one third of the river channel and store 2 years of annual flow. Diverted water irrigates 1.5 million ha of cropland and provides water for industry and domestic use by 22 million people in the southwestern United States and northern Mexico. The native fish community of the lower Colorado River was among the most unique in the world, and the main stem was home to nine freshwater species, all of which were endemic to the basin. Today, five are extirpated, seven are federally endangered, and three are being reintroduced through stocking. Decline of the native fauna is attributed to predation by nonnative fishes and physical habitat degradation. Nearly 80 alien species have been introduced, and more than 20 now are common. These nonnative species thrived in modified habitats, where they largely eliminated the native kinds. As a result, the lower Colorado River has the dubious distinction of being among the few major rivers of the world with an entirely introduced fish fauna. ?? 2005 by the American Fisheries Society.

Spring outmigration of wild and hatchery chinook salmon and steelhead trout smolts from the Imnaha River, Oregon, February 6, 1995--June 20, 1995

International Nuclear Information System (INIS)

Blenden, M.L.; Osborne, R.S.; Kucera, P.A.

1996-01-01

For the second consecutive year, the Nez Perce Tribe, in conjunction with the Fish Passage Center, participated in the smolt monitoring program in the Imnaha River. A rotary screw trap was used to collect emigrating wild and hatchery chinook salmon (Oncorhynchus tshawytscha) and steelhead trout (Oncorhynchus mykiss) smolts from February 6 to June 20, 1995. We PIT tagged and released 421 wild chinook salmon smolts, 747 hatchery chinook salmon smolts (445 HxW and 302 HxH), 227 wild steelhead trout smolts and 1,296 hatchery steelhead trout smolts. Cumulative interrogation rates at mainstem Snake and Columbia River dams were 78.4% for wild chinook salmon, 58.9% for hatchery chinook salmon (HxW), 56.6% for hatchery chinook salmon (HxH), 76.2% for wild steelhead trout, and 69.2% for hatchery steelhead trout. Peak outmigration of NPT tagged wild Imnaha River chinook salmon smolts occurred from early to mid-May at Lower Granite, Little Goose, and Lower Monumental Dams. Median and 90% passage dates for wild chinook salmon smolts at Lower Granite Dam were May 1 and May 11, respectively. Continuous spill at Lower Granite Dam was initiated on May 3 and lasted for 51 days. The 90% passage date of wild chinook salmon smolts at Lower Granite Dam (May 11) preceded peak Snake River and Lower Granite (June 6) flows by 26 days. Although hatchery chinook salmon exhibited a shorter outmigration period through the Snake River than their wild counterparts, peak arrival for both groups occurred at approximately the same time. Median and 90% passage dates at Lower Granite Dam for other PIT tagged groups were: hatchery chinook salmon (NPT-HxW) - May 2 and May 13; hatchery chinook salmon (FPC-HxH) - May 8 and May 15; wild steelhead trout - May 2 and May 9; and hatchery steelhead trout (NPT and FPC) - May 31 and June 16. Hatchery steelhead trout displayed small peaks in arrival timing at Lower Granite and Little Goose Dams in mid-May to mid-June

Centurial Changes in the Depth Conditions of a Regulated River: Case Study of the Lower Tisza River, Hungary

Directory of Open Access Journals (Sweden)

Amissah Gabriel Jonathan

2017-04-01

Full Text Available The Tisza River is the largest tributary of the Danube in Central Europe, and has been subjected to various human interventions including cutoffs to increase the slope, construction of levees to restrict the floodplain, and construction of groynes and revetments to stabilize the channel. These interventions have altered the natural morphological evolution of the river. The aim of the study is to assess the impacts of these engineering works, employing hydrological surveys of 36 cross sections (VO of the Lower Tisza River for the years of 1891, 1931, 1961, 1976 and 1999. The changes in mean depth and thalweg depth were studied in detail comparing three reaches of the studied section. In general, the thalweg incised during the studied period (1891-1931: 3 cm/y; 1931-1961: 1.3 cm/y and 1976-1999: 2.3 cm/y, except from 1961-1976 which was characterized by aggradation (2 cm/y. The mean depth increased, referring to an overall deepening of the river during the whole period (1891-1931: 1.4 cm/y; 1931-1961: 1.2 cm/y; 1961-1976: 0.6 cm/y and 1976-1999: 1.6 cm/y. The thalweg shifted more in the upper reach showing less stabile channel, while the middle and lower reaches had more stable thalweg. Although the cross-sections subjected to various human interventions experienced considerable incision in the short-term, the cross-sections free from direct human impact experienced the largest incision from 1891-1999, especially along the meandering sections.

Temporal-spatial variation of DOC concentration, UV absorbance and the flux estimation in the Lower Dagu River, China

Science.gov (United States)

Xi, Min; Kong, Fanlong; Li, Yue; Kong, Fanting

2017-12-01

Dissolved organic carbon (DOC) is an important component for both carbon cycle and energy balance. The concentration, UV absorbance, and export flux of DOC in the natural environment dominate many important transport processes. To better understand the temporal and spatial variation of DOC, 7 sites along the Lower Dagu River were chosen to conduct a comprehensive measurement from March 2013 to February 2014. Specifically, water samples were collected from the Lower Dagu River between the 26th and 29th of every month during the experimental period. The DOC concentration (CDOC) and UV absorbance were analyzed using a total organic carbon analyzer and the ultraviolet-visible absorption spectrum, and the DOC export flux was estimated with a simple empirical model. The results showed that the CDOC of the Lower Dagu River varied from 1.32 to 12.56 mg/L, consistent with global rivers. The CDOC and UV absorbance showed significant spatial variation in the Dagu River during the experiential period because of the upstream natural processes and human activities in the watershed. The spatial variation is mainly due to dam or reservoir constructions, riverside ecological environment changes, and non-point source or wastewater discharge. The seasonal variation of CDOC was mainly related to the source of water DOC, river runoff, and temperature, and the UV absorbance and humification degree of DOC had no obvious differences among months ( P<0.05). UV absorbance was applied to test the CDOC in Lower Dagu River using wave lengths of 254 and 280 nm. The results revealed that the annual DOC export flux varied from 1.6 to 3.76 × 105 g C/km2/yr in a complete hydrological year, significantly lower than the global average. It is worth mentioning that the DOC export flux was mainly concentrated in summer (˜90% of all-year flux in July and August), since the runoff in the Dagu River took place frequently in summer. These observations implied environment change could bring the temporal

Scoping Assessment for Developing a Water Quality Monitoring Plan to Support Application of the CE-QUAL-W2 Hydrodynamic and Water Quality Model to the Lower Missouri River downstream of Gavins Point Dam

Science.gov (United States)

2010-04-01

setting up input geometry for the Missouri River : 1) channel geometry will be obtained from previous HEC - RAS modeling of the lower Missouri River , and 2...stage-discharge rating curves developed for USGS and USACE gaging stations on the Missouri River . HEC - RAS (Hydrologic Engineering Center- River ...adjusted to better match the “project” table. For the lower Missouri River , initial cell widths will be derived from past HEC - RAS modeling

Evaluation of Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2010

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Diefenderfer, Heida L.; Thom, Ronald M.; Roegner, G. Curtis; Ebberts, Blaine D.; Skalski, John R.; Borde, Amy B.; Dawley, Earl; Coleman, Andre M.; Woodruff, Dana L.; Breithaupt, Stephen A.; Cameron, April; Corbett, C.; Donley, Erin E.; Jay, D. A.; Ke, Yinghai; Leffler, K.; McNeil, C.; Studebaker, Cindy; Tagestad, Jerry D.

2012-05-01

This is the seventh and final annual report of a project (2004–2010) addressing evaluation of the cumulative effects of habitat restoration actions in the 235-km-long lower Columbia River and estuary. The project, called the Cumulative Effects (CE) study, was conducted for the U.S. Army Corps of Engineers Portland District by a collaboration of research agencies led by the Pacific Northwest National Laboratory. We achieved the primary goal of the CE study to develop a methodology to evaluate the cumulative effects of habitat actions in the Columbia Estuary Ecosystem Restoration Program. We delivered 1) standard monitoring protocols and methods to prioritize monitoring activities; 2) the theoretical and empirical basis for a CE methodology using levels-of-evidence; 3) evaluations of cumulative effects using ecological relationships, geo-referenced data, hydrodynamic modeling, and meta-analyses; and 4) an adaptive management process to coordinate and coalesce restoration efforts in the LCRE. A solid foundation has been laid for future comprehensive evaluations of progress made by the Columbia Estuary Ecosystem Restoration Program to understand, conserve, and restore ecosystems in the lower Columbia River and estuary.

Synthetic organic agrochemicals in the lower Mississippi River and its major tributaries--Distribution, transport and fate

Science.gov (United States)

Pereira, W.E.; Rostad, C.E.; Leiker, T.J.

1992-01-01

The Mississippi River and its major tributaries transport herbicides and their degradation products from agricultural areas in the mid-western U.S.A. These compounds include atrazine and its degradation products (desethyl- and desisopropylatrazine), simazine, cyanazine, metolachlor, and alachlor and its degradation products (2-chloro-2′,6′-diethylacetanilide 2-hydroxy-2′,6′-diethylacetanilide and 2,6-diethylaniline). These compounds were identified and confirmed by gas chromatography-ion trap mass spectrometry. Loads of these compounds were determined during five sampling trips in 1987–1989. Stream loads of these compounds indicated that atrazine and metolachlor were relatively conservative in downstream transport. Alachlor and its degradation products were generated from point and non-point sources. Seasonal variations and hydrologic conditions controlled the loads of these compounds in the Mississippi River. Cross-channel mixing was slow downstream from major river confluences, possibly requiring several hundred kilometers of downriver transit for completion. The annual transport of these compounds into the Gulf of Mexico was estimated to be < 2% of the annual application of each herbicide in the Midwest.

Estuarine characteristics of the lower reaches of the River Periyar (Cochin backwater)

Digital Repository Service at National Institute of Oceanography (India)

Sankaranarayanan, V.N.; Varma, P.U.; Balachandran, K.K.; Pylee, A.; Joseph, T.

Lower reaches of river Periyar were studied to assess longitudinal extent of salt water intrusion into the system during different seasons and also its effect on the flushing of pollutants introduced by the industries. During SW monsoon season due...

Land Capability Potential Index (LCPI) and geodatabase for the Lower Missouri River Valley

Science.gov (United States)

Chojnacki, Kimberly A.; Struckhoff, Matthew A.; Jacobson, Robert B.

2012-01-01

The Land Capacity Potential Index (LCPI) is a coarse-scale index intended to delineate broad land-capability classes in the Lower Missouri River valley bottom from the Gavins Point Dam near Yankton, South Dakota to the mouth of the Missouri River near St. Louis, Missouri (river miles 811–0). The LCPI provides a systematic index of wetness potential and soil moisture-retention potential of the valley-bottom lands by combining the interactions among water-surface elevations, land-surface elevations, and the inherent moisture-retention capability of soils. A nine-class wetness index was generated by intersecting a digital elevation model for the valley bottom with sloping water-surface elevation planes derived from eight modeled discharges. The flow-recurrence index was then intersected with eight soil-drainage classes assigned to soils units in the digital Soil Survey Geographic (SSURGO) Database (Soil Survey Staff, 2010) to create a 72-class index of potential flow-recurrence and moisture-retention capability of Missouri River valley-bottom lands. The LCPI integrates the fundamental abiotic factors that determine long-term suitability of land for various uses, particularly those relating to vegetative communities and their associated values. Therefore, the LCPI provides a mechanism allowing planners, land managers, landowners, and other stakeholders to assess land-use capability based on the physical properties of the land, in order to guide future land-management decisions. This report documents data compilation for the LCPI in a revised and expanded, 72-class version for the Lower Missouri River valley bottom, and inclusion of additional soil attributes to allow users flexibility in exploring land capabilities.

Jiecai Han

Indian Academy of Sciences (India)

Home; Journals; Bulletin of Materials Science. Jiecai Han. Articles written in Bulletin of Materials Science. Volume 25 Issue 4 August 2002 pp 263-266 Synthesis. Self-propagating high temperature synthesis and magnetic properties of Ni0.35Zn0.65Fe2O4 powders · Yao Li Jiupeng Zhao Jiecai Han · More Details Abstract ...

Biomass production in the Lower Mississippi River Basin: Mitigating associated nutrient and sediment discharge to the Gulf of Mexico.

Science.gov (United States)

Ha, Miae; Zhang, Zhonglong; Wu, May

2018-04-24

A watershed model was developed using the Soil and Water Assessment Tool (SWAT) that simulates nitrogen, phosphorus, and sediment loadings in the Lower Mississippi River Basin (LMRB). The LMRB SWAT model was calibrated and validated using 21 years of observed flow, sediment, and water-quality data. The baseline model results indicate that agricultural lands within the Lower Mississippi River Basin (LMRB) are the dominant sources of nitrogen and phosphorus discharging into the Gulf of Mexico. The model was further used to evaluate the impact of biomass production, in the presence of riparian buffers in the LMRB, on suspended-sediment and nutrient loading discharge from the Mississippi River into the Gulf of Mexico. The interplay among land use, riparian buffers, crop type, land slope, water quality, and hydrology were anlyzed at various scales. Implementing a riparian buffer in the dominant agricultural region within the LMRB could reduce suspended sediment, nitrogen, and phosphorus loadings at the regional scale by up to 65%, 38%, and 39%, respectively. Implementation of this land management practice can reduce the suspended-sediment content and improve the water quality of the discharge from the LMRB into the Gulf of Mexico and support the potential production of bioenergy and bio-products within the Mississippi River Basin. Copyright © 2017 Elsevier B.V. All rights reserved.

Freshwater mussel assemblage structure in a regulated river in the Lower Mississippi river Alluvial Basin, USA

Science.gov (United States)

Wendell R. Haag; Melvin L. Warren

2007-01-01

1. This paper documents a diverse, reproducing freshwater mussel community (20 species) in Lower Lake } an impounded, regulated portion of the Little Tallahatchie River below Sardis Dam in Panola Co., Mississippi, USA. 2. Despite being regulated and impounded, the lake has a heterogeneous array of habitats that differ markedly in mussel community attributes...

Woolly rhino discovery in the lower Kolyma River

DEFF Research Database (Denmark)

Boeskorov, Gennady G.; Lazarev, Peter A.; Sher, Andrei V.

2011-01-01

A nearly complete frozen mummy of a woolly rhinoceros (Coelodonta antiquitatis Blum., 1799) was discovered in a gold mine on the lower reaches of the Kolyma River, north–eastern Siberia. This is the first find of the whole body of woolly rhino in permafrost. A large part of the mummified body was...... this individual was dated by AMS-radiocarbon method to 39,140 ± 390 years BP (OxA-18755). Spore and pollen analyses of the stomach contents indicate that grasses and sagebrushes formed the main part of the diet of C. antiquitatis in this region of Arctic Siberia....

Lower Genital Tract Trauma in A Tertiary Care Centre in Mid-Western Nepal.

Science.gov (United States)

Adhikari, A K; Dutta, M; Das, C R

2017-01-01

The study of lower genital tract trauma has become important in gynaecological practice. There is paucity of reports on this clinical entity from our settings. The main aim of this study is to document injuries in female lower genital tract in Mid-Western Nepal. Sixty female patients admitted to the hospital with genital tract injuries caused by coitus or accidents were included in the study. Details of the causes of trauma clinical presentations and management were recorded. These injuries were grouped according to etiological factors. This study included 33 (55%) coital injuries and 27 (45%) non- coital injuries. Out of coital injury, 12 cases were criminal assault (rape) in age group of 4 to 18 years. Four unmarried girls had consensual sex. Non-coital injuries were due to fall from height, cattle horn injuries, straddle type of trauma, vulvar haematoma and anorectal injuries. Appropriate surgical intervention can avert morbidity and mortality.

Coal rank, distribution and coalbed methane potential of the lower cretaceous luscar group, Bow River to Blackstone River, Central Alberta Foothills. Bulletin No. 473

Energy Technology Data Exchange (ETDEWEB)

Dawson, F M

1994-12-31

Renewed interest in coal for alternative sources of energy such as coalbed methane have led to an expansion of exploration efforts into areas where the distribution and characterization of the coal resources is not well documented. This paper provides a geological compilation and assessment of the coal distribution and characterization of the Lower Cretaceous Luscar Group for the foothills area from the Bow River to Blackstone River in west-central Alberta. Included with the report are a series of geological maps and cross-sections that highlight the distribution of the coal-bearing strata and potential coalbed methane exploration targets. Field mapping of the area was carried out during the summers of 1988, 1989, and 1990.

Bank Topography, Bathymetry, and Current Velocity of the Lower Elwha River, Clallam County, Washington, May 2006

Science.gov (United States)

Curran, Christopher A.; Konrad, Christopher P.; Dinehart, Randal L.; Moran, Edward H.

2008-01-01

The removal of two dams from the mainstem of the Elwha River is expected to cause a broad range of changes to the river and nearby coastal ecosystem. The U.S. Geological Survey has documented aspects of the condition of the river to allow analysis of ecological responses to dam removal. This report documents the bank topography, river bathymetry, and current velocity data collected along the lower 0.5 kilometer of the Elwha River, May 15-17, 2006. This information supplements nearshore and beach surveys done in 2006 as part of the U.S. Geological Survey Coastal Habitats in Puget Sound program near the Elwha River delta in the Strait of Juan de Fuca, Washington.

Visualization of Flow Alternatives, Lower Missouri River

Science.gov (United States)

Jacobson, Robert B.; Heuser, Jeanne

2002-01-01

Background The U.S. Army Corps of Engineers (COE) 'Missouri River Master Water Control Manual' (Master Manual) review has resulted in consideration of many flow alternatives for managing the water in the river (COE, 2001; 1998a). The purpose of this report is to present flow-management alternative model results in a way that can be easily visualized and understood. This report was updated in October 2001 to focus on the specific flow-management alternatives presented by the COE in the 'Master Manual Revised Draft Environmental Impact Statement' (RDEIS; COE, 2001). The original version (February 2000) is available by clicking here. The COE, U.S. Fish and Wildlife Service (FWS), Missouri River states, and Missouri River basin tribes have been participating in discussions concerning water management of the Missouri River mainstem reservoir system (MRMRS), the Missouri River Bank Stabilization and Navigation Project, and the Kansas River reservoir system since 1986. These discussions include general input to the revision of the Master Manual as well as formal consultation under Section 7 of the Endangered Species Act. In 2000, the FWS issued a Biological Opinion that prescribed changes to reservoir management on the Missouri River that were believed to be necessary to preclude jeopardy to three endangered species, the pallid sturgeon, piping plover, and interior least tern (USFWS, 2000). The combined Missouri River system is large and complex, including many reservoirs, control structures, and free-flowing reaches extending over a broad region. The ability to assess future impacts of altered management scenarios necessarily involves complex, computational models that attempt to integrate physical, chemical, biological, and economic effects. Graphical visualization of the model output is intended to improve understanding of the differences among flow-management alternatives.

A geomorphological assessments of the distribution of sediment sinks along the lower Amazon River

Science.gov (United States)

Park, E.; Latrubesse, E. M.

2017-12-01

Floodplain sediment storage budget is examined along the 1,000 km reach of the lower Amazon River based on extensive sets of remote sensing data and field measurements. Incorporating the washload discharges at gauge stations at the main channel and major tributaries, we analyzed the roles of vast floodplain on the Amazon River seasonal variability in sediment discharges. Annual washload accumulation rate on floodplain along the reach in between Manacapuru and Obidos of is estimated to be 79 Mt over inter-annual average. Period that the net loss over to the floodplain of washload coincide with discharge rising phase of the Amazon River at Obidos, when the river water level rises to make hydrologic connections to floodplain. Only during the early falling phase (July-August), 3.6 Mt of washload net gain occurred in a year, which was less than 5% of the annual net loss to the floodplain. To assess the spatial distribution of sediment sinks along the lower Amazon, we incorporated various hydro-geomorphic factors regarding floodplain geomorphic styles and morphometric parameters, such floodplain width, levee heights, water-saturated area, suspended sediment distribution over floodplain and distribution of impeded floodplain. Impeded floodplain that contains numerous large rounded lakes is the definition of active sediment sinks along the lower Amazon, which seasonally stores most of the water and traps sediment from the river. The results of these hydro-geomorphic factors collectively indicate that the extent and magnitudes of sediment sinks becomes larger downstream (from Manacapuru to Monte Alegre), which is proportionally related to the development of the water-saturated floodplain. This indicates the nonlinear geomorphic evolution of the Amazon floodplain through its longitudinal profile since the late Holocene that downstream reaches are still to be infilled with sediments (incomplete floodplain) thus acting as sediment sinks.

Anticipated sediment delivery to the lower Elwha River during and following dam removal: Chapter 2 in Coastal habitats of the Elwha River, Washington--biological and physical patterns and processes prior to dam removal

Science.gov (United States)

Czuba, Christiana R.; Randle, Timothy J.; Bountry, Jennifer A.; Magirl, Christopher S.; Czuba, Jonathan A.; Curran, Christopher A.; Konrad, Christopher P.; Duda, Jeffrey J.; Warrick, Jonathan A.; Magirl, Christopher S.

2011-01-01

During and after the planned incremental removal of two large, century-old concrete dams between 2011 and 2014, the sediment-transport regime in the lower Elwha River of western Washington will initially spike above background levels and then return to pre-dam conditions some years after complete dam removal. Measurements indicate the upper reaches of the steep-gradient Elwha River, draining the northeast section of the Olympic Mountains, carries between an estimated 120,000 and 290,000 cubic meters of sediment annually. This large load has deposited an estimated 19 million cubic meters of sediment within the two reservoirs formed by the Elwha and Glines Canyon Dams. It is anticipated that from 7 to 8 million cubic meters of this trapped sediment will mobilize and transport downstream during and after dam decommissioning, restoring the downstream sections of the sediment-starved river and nearshore marine environments. Downstream transport of sediment from the dam sites will have significant effects on channel morphology, water quality, and aquatic habitat during and after dam removal. Sediment concentrations are expected to be between 200 and 1,000 milligrams per liter during and just after dam removal and could rise to as much as 50,000 milligrams per liter during high flows. Downstream sedimentation in the river channel and flood plain will be potentially large, particularly in the lower Elwha River, an alluvial reach with a wide flood plain. Overall aggradation could be as much as one to several meters. Not all reservoir sediment, however, will be released to the river. Some material will remain on hill slopes and flood plains within the drained reservoirs in quantities that will depend on the hydrology, precipitation, and mechanics of the incising channel. Eventually, vegetation will stabilize this remaining reservoir sediment, and the overall sediment load in the restored river will return to pre-dam levels.

Seasonal Juvenile Salmonid Presence and Migratory Behavior in the Lower Columbia River

Energy Technology Data Exchange (ETDEWEB)

Carter, Jessica A.; McMichael, Geoffrey A.; Welch, Ian D.; Harnish, Ryan A.; Bellgraph, Brian J.

2009-04-30

To facilitate preparing Biological Assessments of proposed channel maintenance projects, the Portland District of the U.S. Army Corps of Engineers contracted the Pacific Northwest National Laboratory to consolidate and synthesize available information about the use of the lower Columbia River and estuary by juvenile anadromous salmonids. The information to be synthesized included existing published documents as well as data from five years (2004-2008) of acoustic telemetry studies conducted in the Columbia River estuary using the Juvenile Salmon Acoustic Telemetry System. For this synthesis, the Columbia River estuary includes the section of the Columbia River from Bonneville Dam at river kilometer (Rkm) 235 downstream to the mouth where it enters the Pacific Ocean. In this report, we summarize the seasonal salmonid presence and migration patterns in the Columbia River estuary based on information from published studies as well as relevant data from acoustic telemetry studies conducted by NOAA Fisheries and the Pacific Northwest National Laboratory (PNNL) between 2004 and 2008. Recent acoustic telemetry studies, conducted using the Juvenile Salmon Acoustic Telemetry System (JSATS; developed by the Portland District of the U.S. Army Corps of Engineers), provided information on the migratory behavior of juvenile steelhead (O. mykiss) and Chinook salmon in the Columbia River from Bonneville Dam to the Pacific Ocean. In this report, Section 2 provides a summary of information from published literature on the seasonal presence and migratory behavior of juvenile salmonids in the Columbia River estuary and plume. Section 3 presents a detailed synthesis of juvenile Chinook salmon and steelhead migratory behavior based on use of the JSATS between 2004 and 2008. Section 4 provides a discussion of the information summarized in the report as well as information drawn from literature reviews on potential effects of channel maintenance activities to juvenile salmonids rearing in

Examining the spatial and temporal variation of groundwater inflows to a valley-to-floodplain river using 222Rn, geochemistry and river discharge: the Ovens River, southeast Australia

Science.gov (United States)

Yu, M. C. L.; Cartwright, I.; Braden, J. L.; de Bree, S. T.

2013-12-01

Radon (222Rn) and major ion geochemistry were used to define and quantify the catchment-scale groundwater-surface water interactions along the Ovens River in the southeast Murray-Darling Basin, Victoria, Australia, between September 2009 and October 2011. The Ovens River is characterized by the transition from a single channel within a mountain valley in the upper catchment to a multi-channel meandering river on flat alluvial plains in the lower catchment. Overall, the Ovens River is dominated by gaining reaches, receiving groundwater from both alluvial and basement aquifers. The distribution of gaining and losing reaches is governed by catchment morphology and lithology. In the upper catchment, rapid groundwater recharge through the permeable aquifers increases the water table. The rising water table, referred to as hydraulic loading, increases the hydraulic head gradient toward the river and hence causes high baseflow to the river during wet (high flow) periods. In the lower catchment, lower rainfall and finer-gained sediments reduce the magnitude and variability of hydraulic gradient between the aquifer and the river, producing lower but more constant groundwater inflows. The water table in the lower reaches has a shallow gradient, and small changes in river height or groundwater level can result in fluctuating gaining and losing behaviour. The middle catchment represents a transition in river-aquifer interactions from the upper to the lower catchment. High baseflow in some parts of the middle and lower catchments is caused by groundwater flowing over basement highs. Mass balance calculations based on 222Rn activities indicate that groundwater inflows are 2 to 17% of total flow with higher inflows occurring during high flow periods. In comparison to 222Rn activities, estimates of groundwater inflows from Cl concentrations are higher by up to 2000% in the upper and middle catchment but lower by 50 to 100% in the lower catchment. The high baseflow estimates using

Changing Course: navigating the future of the Lower Mississippi River

Science.gov (United States)

Cochran, S.

2016-02-01

Changing Course is a design competition to reimagine a more sustainable Lower Mississippi River Delta, bringing teams together from around the world to create innovative visions for one of America's greatest natural resources. Building off of Louisiana's Coastal Master Plan, and answering a key question from that plan, three winning teams (Baird & Associates, Moffatt & Nichol and Studio Misi-Ziibi) have generated designs for how the Mississippi River's water and sediment can be used to maximize rebuilding of delta wetlands while also continuing to meet the needs of navigation, flood protection, and coastal industries and communities. While each of the winning teams offered a different vision, all three identified the same key requirements as critical to sustaining the Mississippi River Delta today and into the future: Reconnecting the Mississippi River to its wetlands to help restore southeast Louisiana's first line of defense against powerful storms and rising sea levels. Planning for a more sustainable delta, including a gradual shift in population to create more protected and resilient communities. Protecting and maximizing the region's port and maritime activities, including a deeper more sustainable navigation channel upriver from Southwest Pass. Increasing economic opportunities in a future smaller delta through expanding shipping capacity, coastal restoration infrastructure, outdoor recreation and tourism and commercial fishing. This session will give a high level overview of the design competition process, results and common themes, similarities and differences in their designs, and how the ideas generated will inform coastal stakeholders and official government processes.

Fishes in paleochannels of the Lower Mississippi River alluvial valley: A national treasure

Science.gov (United States)

Miranda, Leandro E.

2016-01-01

Fluvial geomorphology of the alluvial valley of the Lower Mississippi River reveals a fascinating history. A prominent occupant of the valley was the Ohio River, estimated to have flowed 25,000 years ago over western Tennessee and Mississippi to join the Mississippi River north of Baton Rouge, Louisiana, 750–800 km south of the present confluence. Over time, shifts in the Mississippi and Ohio rivers toward their contemporary positions have left a legacy of abandoned paleochannels supportive of unique fish assemblages. Relative to channels abandoned in the last 500 years, paleochannels exhibit harsher environmental conditions characteristic of hypereutrophic lakes and support tolerant fish assemblages. Considering their ecological, geological, and historical importance, coupled with their primordial scenery, the hundreds of paleochannels in the valley represent a national treasure. Altogether, these waterscapes are endangered by human activities and would benefit from the conservation attention afforded to our national parks and wildlife refuges.

The passive river restoration approach as an efficient tool to improve the hydromorphological diversity of rivers - Case study from two river restoration projects in the German lower mountain range

Science.gov (United States)

Groll, M.

2017-09-01

Intensive use of European rivers during the last hundreds of years has led to profound changes in the physicochemical properties, river morphology, and aquatic faunistic communities. Rectifying these changes and improving the ecological state of all surface water bodies is the central aim of the European Water Frame Directive (WFD), and river restoration measures are the main tool to achieve this goal for many rivers. As the cost-effectiveness of all measures is crucial to the WFD implementation, the approach of the passive river restoration has become very popular over the last decades. But while costs of this approach are minimal, not much is known about the long-term effectiveness of passive river restorations. The research presented here provides essential and in-depth data about the effects of two such restoration measures on the riverbed morphology of a large river of the lower mountain region in Germany (type 9.2). More than 3200 data sets were acquired using the TRiSHa method (Typology of Riverbed Structures and Habitats). The results show a high spatial and temporal diversity and dynamic for all analyzed hydromorphologic parameters - ranging from riverbed sediments, organic structures like dead wood or macrophytes, to the distribution of 32 microhabitat types. The structures and their dynamic depend on the character of the study area (free-flowing or impounded), the location of the study sites within the research area (main channel or restored side channel), and on the occurrence of major flood events (the mapping and sampling were conducted annually from 2006 to 2008 with a 50-year flood event occurring in early 2007). These results show the potential of the passive restoration approach for creating morphologically diverse riverbeds, as habitat diversity and the spatial heterogeneity of the riverbed substrates increased significantly (e.g., more than 40% of all habitat types were only detected in the newly restored side channels). But the results also

Sediment budget as affected by construction of a sequence of dams in the lower Red River, Viet Nam

Science.gov (United States)

Lu, Xi Xi; Oeurng, Chantha; Le, Thi Phuong Quynh; Thuy, Duong Thi

2015-11-01

Dam construction is one of the main factors resulting in riverine sediment changes, which in turn cause river degradation or aggradation downstream. The main objective of this work is to examine the sediment budget affected by a sequence of dams constructed upstream in the lower reach of the Red River. The study is based on the longer-term annual data (1960-2010) with a complementary daily water and sediment data set (2008-2010). The results showed that the stretch of the river changed from sediment surplus (suggesting possible deposition processes) into sediment deficit (possible erosion processes) after the first dam (Thac Ba Dam) was constructed in 1972 and changed back to deposition after the second dam (Hoa Binh Dam) was constructed in 1985. The annual sediment deposition varied between 1.9 Mt/y and 46.7 Mt/y with an annual mean value of 22.9 Mt/y (1985-2010). The sediment deposition at the lower reach of the Red River would accelerate river aggradation which would change river channel capacity in the downstream of the Red River. The depositional processes could be sustained or changed back to erosional processes after more dams (the amount of sediment deposit was much less after the latest two dams Tuyen Quang Dam in 2009 and Sonla Dam in 2010) are constructed, depending on the water and sediment dynamics. This study revealed that the erosional and depositional processes could be shifted for the same stretch of river as affected by a sequence of dams and provides useful insights in river management in order to reduce flood frequency along the lower reach of the Red River.

Sources of suspended-sediment loads in the lower Nueces River watershed, downstream from Lake Corpus Christi to the Nueces Estuary, south Texas, 1958–2010

Science.gov (United States)

Ockerman, Darwin J.; Heitmuller, Franklin T.; Wehmeyer, Loren L.

2013-01-01

The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, Fort Worth District; City of Corpus Christi; Guadalupe-Blanco River Authority; San Antonio River Authority; and San Antonio Water System, developed, calibrated, and tested a Hydrological Simulation Program-FORTRAN (HSPF) watershed model to simulate streamflow and suspended-sediment concentrations and loads during 1958-2010 in the lower Nueces River watershed, downstream from Lake Corpus Christi to the Nueces Estuary in south Texas. Data available to simulate suspended-sediment concentrations and loads consisted of historical sediment data collected during 1942-82 in the study area and suspended-sediment concentration data collected periodically by the USGS during 2006-7 and 2010 at three USGS streamflow-gaging stations (08211000 Nueces River near Mathis, Tex. [the Mathis gage], 08211200 Nueces River at Bluntzer, Tex. [the Bluntzer gage], and 08211500 Nueces River at Calallen, Tex. [the Calallen gage]), and at one ungaged location on a Nueces River tributary (USGS station 08211050 Bayou Creek at Farm Road 666 near Mathis, Tex.). The Mathis gage is downstream from Wesley E. Seale Dam, which was completed in 1958 to impound Lake Corpus Christi. Suspended-sediment data collected before and after completion of Wesley E. Seale Dam provide insights to the effects of the dam and reservoir on suspended-sediment loads transported by the lower Nueces River downstream from the dam to the Nueces Estuary. Annual suspended-sediment loads at the Nueces River near the Mathis, Tex., gage were considerably lower for a given annual mean discharge after the dam was completed than before the dam was completed.

Temporal variability in terrestrially-derived sources of particulate organic carbon in the lower Mississippi River and its upper tributaries

Science.gov (United States)

Bianchi, Thomas S.; Wysocki, Laura A.; Stewart, Mike; Filley, Timothy R.; McKee, Brent A.

2007-09-01

In this study, we examined the temporal changes of terrestrially-derived particulate organic carbon (POC) in the lower Mississippi River (MR) and in a very limited account, the upper tributaries (Upper MR, Ohio River, and Missouri River). We used for the first time a combination of lignin-phenols, bulk stable carbon isotopes, and compound-specific isotope analyses (CSIA) to examine POC in the lower MR and upper tributaries. A lack of correlation between POC and lignin phenol abundances ( Λ8) was likely due to dilution effects from autochthonous production in the river, which has been shown to be considerably higher than previously expected. The range of δ 13C values for p-hydroxycinnamic and ferulic acids in POC in the lower river do support that POM in the lower river does have a significant component of C 4 in addition to C 3 source materials. A strong correlation between δ 13C values of p-hydroxycinnamic, ferulic, and vanillyl phenols suggests a consistent input of C 3 and C 4 carbon to POC lignin while a lack of correlation between these same phenols and POC bulk δ 13C further indicates the considerable role of autochthonous carbon in the lower MR POC budget. Our estimates indicate an annual flux of POC of 9.3 × 10 8 kg y -1 to the Gulf of Mexico. Total lignin fluxes, based on Λ8 values of POC, were estimated to be 1.2 × 10 5 kg y -1. If we include the total dissolved organic carbon (DOC) flux (3.1 × 10 9 kg y -1) reported by [Bianchi T. S., Filley T., Dria K. and Hatcher, P. (2004) Temporal variability in sources of dissolved organic carbon in the lower Mississippi River. Geochim. Cosmochim. Acta68, 959-967.], we get a total organic carbon flux of 4.0 × 10 9 kg y -1. This represents 0.82% of the annual total organic carbon supplied to the oceans by rivers (4.9 × 10 11 kg).

Slabs and plumes crossing a broad density/viscosity discontinuity in the mid lower mantle (Invited)

Science.gov (United States)

Morra, G.; Yuen, D. A.; Cammarano, F.

2010-12-01

The depth-dependence of the viscosity is not well constrained by observations alone. Non-monotonic viscosity profiles have been often proposed in the past and are in the range of possible solutions. Such viscosity structures find new vigor on the light of recent discoveries of iron-spin transition in mantle minerals and their consequences on seismic interpretation [1] and dynamical evolution of the mantle. Using the recently introduced Multipole-Accelerated Boundary Element Method, we study the entire space of possible models of plumes and slabs crossing a broad region where mantle viscosity and/or density are non-monotonic [2]. The viscosity peak considered are 1, to 100 times then the rest of the mantle, while the density step considered is 0 to 2% different from the adiabatic profile. We identify the critical viscosity and density profiles that produce stalling or penetration of slabs and the continuous or intermittent penetration of plumes through the mid lower mantle. Based on our results, we envisage possible dynamic scenarios that would separate the mantle in two regions,suggesting a long term bifurcation originating, probably, from the spin transition itself. References: [1] Cammarano, F.; Marquardt, H.; Speziale, S.; Tackley, P. J., 2010, Role of iron-spin transition in ferropericlase on seismic interpretation: A broad thermochemical transition in the mid mantle? Geophysical Research Letters, Volume 37, Issue 3, CiteID L03308 [2] G. Morra, D. A. Yuen, L. Boschi, P. Chatelain, P. Koumoutzakos and P. Tackley, 2010, The fate of the slabs interacting with a smooth viscosity discontinuity in the mid lower mantle, Physics of the Earth and Planetary Interiors, Volume 180, Issues 3-4, 271-282, doi:10.1016/j.pepi.2010.04.001

The first Koç Han: Pioneering modern architecture in Ankara

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Oya Atalay Franck

2013-01-01

Full Text Available Koç Holding is the most established conglomerate in Turkey. Th e company’s beginnings date from the mid 1920s, when Ahmet Vehbi Koç, founder of Koç Holding, had his first own company registered with the Ankara Chamber of Commerce. In 1932, Koç moved his business from his father’s store on Anafartalar Street to a new building, the first Koç Han, erected the same year on Çankırı Street Nr.13 in Ulus. Th e building’s designer was Swiss-Austrian architect Ernst Arnold Egli, who had come to Turkey only five years earlier upon invitation by the government to work as chief architect of the Ministry of National Education. During his stay, which lasted from 1927 until 1940, Egli realized about 40 projects and worked on many more. Koç Han is the rare example of a commercial building by Egli. At a time when the urban aspect of the old town center of Ankara consisted mostly of one-or two-storeyed stone-and-wood houses, the first Koç Han represented an altogether new building type for the town, in being a multipurpose edifice with space for shops at street level, with large storage facilities below ground, and providing off ices and housing on the upper fl oors. Th e functional rigor of the plan and the sober modernism of the building’s facades contrasted strongly with the architecture of the time. In this respect, the first Koç Han was a strong statement regarding Ahmet Vehbi Koç’s belief in a modern Turkey and to the contribution of the building’s architect, Ernst Arnold Egli, to this project.

Pre- and post-impoundment nitrogen in the lower Missouri River

Science.gov (United States)

Blevins, Dale W.; Wilkison, Donald H.; Niesen, Shelley L.

2013-01-01

Large water-sample sets collected from 1899 through 1902, 1907, and in the early 1950s allow comparisons of pre-impoundment and post-impoundment (1969 through 2008) nitrogen concentrations in the lower Missouri River. Although urban wastes were not large enough to detectably increase annual loads of total nitrogen at the beginning of the 20th century, carcass waste, stock-yard manure, and untreated human wastes measurably increased ammonia and organic-nitrogen concentrations during low flows. Average total-nitrogen concentrations in both periods were about 2.5 mg/l, but much of the particulate-organic nitrogen, which was the dominant form of nitrogen around 1900, has been replaced by nitrate. This change in speciation was caused by the nearly 80% decrease in suspended-sediment concentrations that occurred after impoundment, modern agriculture, drainage of riparian wetlands, and sewage treatment. Nevertheless, bioavailable nitrogen has not been low enough to limit primary production in the Missouri River since the beginning of the 20th century. Nitrate concentrations have increased more rapidly from 2000 through 2008 (5 to 12% per year), thus increasing bioavailable nitrogen delivered to the Mississippi River and affecting Gulf Coast hypoxia. The increase in nitrate concentrations with distance downstream is much greater during the post-impoundment period. If strategies to decrease total-nitrogen loads focus on particulate N, substantial decreases will be difficult because particulate nitrogen is now only 23% of total nitrogen in the Missouri River. A strategy aimed at decreasing particulates also could further exacerbate land loss along the Gulf of Mexico, which has been sediment starved since Missouri River impoundment. In contrast, strategies or benchmarks aimed at decreasing nitrate loads could substantially decrease nitrogen loadings because nitrates now constitute over half of the Missouri's nitrogen input to the Mississippi. Ongoing restoration and creation

Particle tracking for selected groundwater wells in the lower Yakima River Basin, Washington

Science.gov (United States)

Bachmann, Matthew P.

2015-10-21

The Yakima River Basin in south-central Washington has a long history of irrigated agriculture and a more recent history of large-scale livestock operations, both of which may contribute nutrients to the groundwater system. Nitrate concentrations in water samples from shallow groundwater wells in the lower Yakima River Basin exceeded the U.S. Environmental Protection Agency drinking-water standard, generating concerns that current applications of fertilizer and animal waste may be exceeding the rate at which plants can uptake nutrients, and thus contributing to groundwater contamination.

Water-quality assessment of the lower Illinois River Basin; environmental setting

Science.gov (United States)

Warner, Kelly L.

1998-01-01

The lower Illinois River Basin (LIRB) encompasses 18,000 square miles of central and western Illinois. Historical and recent information from Federal, State, and local agencies describing the physiography, population, land use, soils, climate, geology, streamflow, habitat, ground water, water use, and aquatic biology is summarized to describe the environmental setting of the LIRB. The LIRB is in the Till Plains Section of the Central Lowland physiographic province. The basin is characterized by flat topography, which is dissected by the Illinois River. The drainage pattern of the LIRB has been shaped by many bedrock and glacial geologic processes. Erosion prior to and during Pleistocene time created wide and deep bedrock valleys. The thickest deposits and most major aquifers are in buried bedrock valleys. The Wisconsinan glaciation, which bisects the northern half of the LIRB, affects the distribution and characteristics of glacial deposits in the basin. Agriculture is the largest land use and forested land is the second largest land use in the LIRB. The major urban areas are near Peoria, Springfield, Decatur, and Bloomington-Normal. Soil type and distribution affect the amount of soil erosion, which results in sedimentation of lakes and reservoirs in the basin. Rates of soil erosion of up to 2 percent per year of farmland soil have been measured. Many of the 300 reservoirs, lakes, and wetlands are disappearing because of sedimentation resulting from agriculture activities, levee building, and urbanization. Sedimentation and the destruction of habitat appreciably affect the ecosystem. The Illinois River is a large river-floodplain ecosystem where biological productivity is enhanced by annual flood pulses that advance and retreat over the flood plain and temporarily expand backwater and flood-plain lakes. Ground-water discharge to streams affects the flow and water quality of the streams. The water budget of several subbasins show variability in ground

Development of a channel classification to evaluate potential for cottonwood restoration, lower segments of the Middle Missouri River, South Dakota and Nebraska

Science.gov (United States)

Jacobson, Robert B.; Elliott, Caroline M.; Huhmann, Brittany L.

2010-01-01

This report documents development of a spatially explicit river and flood-plain classification to evaluate potential for cottonwood restoration along the Sharpe and Fort Randall segments of the Middle Missouri River. This project involved evaluating existing topographic, water-surface elevation, and soils data to determine if they were sufficient to create a classification similar to the Land Capability Potential Index (LCPI) developed by Jacobson and others (U.S. Geological Survey Scientific Investigations Report 2007–5256) and developing a geomorphically based classification to apply to evaluating restoration potential.Existing topographic, water-surface elevation, and soils data for the Middle Missouri River were not sufficient to replicate the LCPI. The 1/3-arc-second National Elevation Dataset delineated most of the topographic complexity and produced cumulative frequency distributions similar to a high-resolution 5-meter topographic dataset developed for the Lower Missouri River. However, lack of bathymetry in the National Elevation Dataset produces a potentially critical bias in evaluation of frequently flooded surfaces close to the river. High-resolution soils data alone were insufficient to replace the information content of the LCPI. In test reaches in the Lower Missouri River, soil drainage classes from the Soil Survey Geographic Database database correctly classified 0.8–98.9 percent of the flood-plain area at or below the 5-year return interval flood stage depending on state of channel incision; on average for river miles 423–811, soil drainage class correctly classified only 30.2 percent of the flood-plain area at or below the 5-year return interval flood stage. Lack of congruence between soil characteristics and present-day hydrology results from relatively rapid incision and aggradation of segments of the Missouri River resulting from impoundments and engineering. The most sparsely available data in the Middle Missouri River were water

Yukon River King Salmon - Ichthyophonus Pilot Study

Science.gov (United States)

Kocan, R.M.; Hershberger, P.K.

2001-01-01

When king salmon enter the Yukon River on their spawning migration in mid June, over 25% of the population are infected with Ichthyophonus. The percent of infected fish remains relatively constant until the fish pass river mile 1,319 at Dawson, Y.T., then it drops to 13% when they reach river mile 1,745 at Whitehorse, Y.T. When the sexes are examined separately, slightly more females are infected than males (29% vs 22%). The percent of fish exhibiting clinical signs (diseased) is 2-3% when they enter the river, but increases to over 20% at river mile 715 near Tanana, AK. Disease prevalence within the population remains constant at >20% until fish pass Dawson, then the percent of diseased fish drops to <9% at Whitehorse. When the sexes are examined separately, male disease prevalence is highest at Tanana (22.6%) then gradually drops to just 12.9% at Whitehorse. Females however, continue to show an increase in disease prevalence peaking at river mile 1,081 near Circle, AK, at 36.4%, then dropping to just 5.3% at Whitehorse. Data on infection and disease collected from kings at Nenana on the Tanana River more closely resembles that seen at Whitehorse than the lower and middle Yukon River.

Hans Pöhl - Estlandssvenskarnas hövding = Hans Pöhl - rannarootslaste eestvõitleja / Torkel Jansson

Index Scriptorium Estoniae

Jansson, Torkel, 1947-

2011-01-01

Raamatututvustus: Hans Pöhl - Estlandssvenskarnas hövding : en biografi över Hans Pöhl (1876-1930), estlandssvenskarnas främste företrädare och ledare = Hans Pöhl - rannarootslaste eestvõitleja : Hans Pöhli (1876-1930), Eesti rootslaste vaimse liidri ja valgustaja elulugu. (Stockholm ; Tallinn, 2010)

Long-term controls on continental-scale bedrock river terrace deposition from integrated clast and heavy mineral assemblage analysis: An example from the lower Orange River, Namibia

Science.gov (United States)

Nakashole, Albertina N.; Hodgson, David M.; Chapman, Robert J.; Morgan, Dan J.; Jacob, Roger J.

2018-02-01

Establishing relationships between the long-term landscape evolution of drainage basins and the fill of sedimentary basins benefits from analysis of bedrock river terrace deposits. These fragmented detrital archives help to constrain changes in river system character and provenance during sediment transfer from continents (source) to oceans (sink). Thick diamondiferous gravel terrace deposits along the lower Orange River, southern Namibia, provide a rare opportunity to investigate controls on the incision history of a continental-scale bedrock river. Clast assemblage and heavy mineral data from seven localities permit detailed characterisation of the lower Orange River gravel terrace deposits. Two distinct fining-upward gravel terrace deposits are recognised, primarily based on mapped stratigraphic relationships (cross-cutting relationships) and strath and terrace top elevations, and secondarily on the proportion of exotic clasts, referred to as Proto Orange River deposits and Meso Orange River deposits. The older early to middle Miocene Proto Orange River gravels are thick (up to 50 m) and characterised by a dominance of Karoo Supergroup shale and sandstone clasts, whereas the younger Plio-Pleistocene Meso Orange River gravels (6-23 m thick) are characterised by more banded iron formation clasts. Mapping of the downstepping terraces indicates that the Proto gravels were deposited by a higher sinuosity river, and are strongly discordant to the modern Orange River course, whereas the Meso deposits were deposited by a lower sinuosity river. The heavy minerals present in both units comprise magnetite, garnet, amphibole, epidote and ilmenite, with rare titanite and zircon grains. The concentration of amphibole-epidote in the heavy minerals fraction increases from the Proto to the Meso deposits. The decrease in incision depths, recorded by deposit thicknesses above strath terraces, and the differences in clast character (size and roundness) and type between the two

Variations in selected water quality variables and metal concentrations in the sediment of the lower Olifants and Selati rivers, South Africa

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T. Seymore

1994-08-01

Full Text Available A survey of the water and sediment quality of the lower Olifants River and lower Selati River was carried out. Metal concentrations (Cr, Cu, Fe, Mn, Ni, Pb, Sr and Zn in the water and sediment, as well as the physical and chemical characteristics of the water were determined over a two-year period (April 1990 - February 1992. The water quality of the lower Selati River, which flows through the Phalaborwa area, was found to be influenced by the mining and industrial activities in the area. It was also the case with the lower Olifants River after the Selati-Olifants confluence, although the concentrations of most variables did decrease from the western side of the Kruger National Park to the eastern side due to dilution of the water by tributaries of the Olifants River. Variables of special concern were sodium, fluoride. chloride, sulphate, potassium, the total dissolved salts and the metal concentrations (except strontium. The water quality of the Selati River in the study area is a great cause of concern and a further degradation thereof cannot be afforded.

Pesticide Occurrence and Distribution in the Lower Clackamas River Basin, Oregon, 2000-2005

Science.gov (United States)

Carpenter, Kurt D.; Sobieszczyk, Steven; Arnsberg, Andrew J.; Rinella, Frank A.

2008-01-01

Pesticide occurrence and distribution in the lower Clackamas River basin was evaluated in 2000?2005, when 119 water samples were analyzed for a suite of 86?198 dissolved pesticides. Sampling included the lower-basin tributaries and the Clackamas River mainstem, along with paired samples of pre- and post-treatment drinking water (source and finished water) from one of four drinking water-treatment plants that draw water from the lower river. Most of the sampling in the tributaries occurred during storms, whereas most of the source and finished water samples from the study drinking-water treatment plant were obtained at regular intervals, and targeted one storm event in 2005. In all, 63 pesticide compounds were detected, including 33 herbicides, 15 insecticides, 6 fungicides, and 9 pesticide degradation products. Atrazine and simazine were detected in about half of samples, and atrazine and one of its degradates (deethylatrazine) were detected together in 30 percent of samples. Other high-use herbicides such as glyphosate, triclopyr, 2,4-D, and metolachlor also were frequently detected, particularly in the lower-basin tributaries. Pesticides were detected in all eight of the lower-basin tributaries sampled, and were also frequently detected in the lower Clackamas River. Although pesticides were detected in all of the lower basin tributaries, the highest pesticide loads (amounts) were found in Deep and Rock Creeks. These medium-sized streams drain a mix of agricultural land (row crops and nurseries), pastureland, and rural residential areas. The highest pesticide loads were found in Rock Creek at 172nd Avenue and in two Deep Creek tributaries, North Fork Deep and Noyer Creeks, where 15?18 pesticides were detected. Pesticide yields (loads per unit area) were highest in Cow and Carli Creeks, two small streams that drain the highly urban and industrial northwestern part of the lower basin. Other sites having relatively high pesticide yields included middle Rock Creek and

Estimation of potential runoff-contributing areas in the Kansas-Lower Republican River Basin, Kansas

Science.gov (United States)

Juracek, Kyle E.

1999-01-01

Digital soils and topographic data were used to estimate and compare potential runoff-contributing areas for 19 selected subbasins representing soil, slope, and runoff variability within the Kansas-Lower Republican (KLR) River Basin. Potential runoff-contributing areas were estimated separately and collectively for the processes of infiltration-excess and saturation-excess overland flow using a set of environmental conditions that represented high, moderate, and low potential runoff. For infiltration-excess overland flow, various rainfall intensities and soil permeabilities were used. For saturation-excess overland flow, antecedent soil-moisture conditions and a topographic wetness index were used. Results indicated that the subbasins with relatively high potential runoff are located in the central part of the KLR River Basin. These subbasins are Black Vermillion River, Clarks Creek, Delaware River upstream from Muscotah, Grasshopper Creek, Mill Creek (Wabaunsee County), Soldier Creek, Vermillion Creek (Pottawatomie County), and Wildcat Creek. The subbasins with relatively low potential runoff are located in the western one-third of the KLR River Basin, with one exception, and are Buffalo Creek, Little Blue River upstream from Barnes, Mill Creek (Washington County), Republican River between Concordia and Clay Center, Republican River upstream from Concordia, Wakarusa River downstream from Clinton Lake (exception), and White Rock Creek. The ability to distinguish the subbasins as having relatively high or low potential runoff was possible mostly due to the variability of soil permeability across the KLR River Basin.

RiverFlow2D numerical simulation of flood mitigation solutions in the Ebro River

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I. Echeverribar

2017-01-01

Full Text Available A study of measures oriented to flood mitigation in the mid reach of the Ebro river is presented: elimination of vegetation in the riverbed, use of controlled flooding areas and construction or re-adaptation of levees. The software used is RiverFlow2D which solves the conservative free-surface flow equations with a finite volume method running on GPU. The results are compared with measurements at gauge stations and aerial views. The most effective measure has turned out to be the elimination of vegetation in the riverbed. It is demonstrated that not only the maximum flooded area is narrower but also it reduces the water depth up to 1 m. The other measures have local consequences when the peak discharge is relatively high although they could be useful in case the discharge is lower.

Food habits of Juvenile American Shad and dynamics of zooplankton in the lower Columbia River

Science.gov (United States)

Haskell, C.A.; Tiffan, K.F.; Rondorf, D.W.

2006-01-01

As many as 2.4 million adult American shad annually pass John Day Dam, Columbia River to spawn upriver, yet food web interactions of juvenile shad rearing in John Day Reservoir are unexplored. We collected zooplankton and conducted mid-water trawls in McNary (June-July) and John Day reservoirs (August-November) from 1994 through 1996 during the outmigration of subyearling American shad and Chinook salmon. Juvenile American shad were abundant and represented over 98% of the trawl catch in late summer. The five major taxa collected in zooplankton tows were Bosmina longirostris, Daphnia, cyclopoid cope-pods, rotifers, and calanoid copepods. We evaluated total crustacean zooplankton abundance and Daphnia biomass in relation to water temperature, flow, depth, diel period, and cross-sectional location using multiple regression. Differences in zooplankton abundance were largely due to differences in water temperature and flow. Spatial variation in total zooplankton abundance was observed in McNary Reservoir, but not in John Day Reservoir. Juvenile American shad generally fed on numerically abundant prey, despite being less preferred than larger bodied zooplankton. A decrease in cladoceran abundance and size in August coupled with large percentages of Daphnia in juvenile American shad stomachs indicated heavy planktivory. Smaller juvenile American shad primarily fed on Daphnia in August, but switched to more evasive copepods as the mean size of fish increased and Daphnia abundance declined. Because Daphnia are particularly important prey items for subyearling Chinook salmon in mainstem reservoirs in mid to late summer, alterations in the cladoceran food base is of concern for the management of outmigrating salmonids and other Columbia River fishes. ?? 2006 by the Northwest Scientific Association. All rights reserved.

Freshwater Ecosystem Services and Hydrologic Alteration in the Lower Mississippi River Basin

Science.gov (United States)

Yasarer, L.; Taylor, J.; Rigby, J.; Locke, M. A.

2017-12-01

Flowing freshwater ecosystems provide a variety of essential ecosystem services including: consumptive water for domestic, industrial, and agricultural use; transportation of goods; maintenance of aquatic biodiversity and water quality; and recreation. However, freshwater ecosystem services can oftentimes be at odds with each other. For example, the over-consumption of water for agricultural production or domestic use may alter hydrologic patterns and diminish the ability of flowing waters to sustain healthy aquatic ecosystems. In the Lower Mississippi River Basin there has been a substantial increase in groundwater-irrigated cropland acreage over the past several decades and subsequent declines in regional aquifer levels. Changes in aquifer levels potentially impact surface water hydrology throughout the region. This study tests the hypothesis that flowing water systems in lowland agricultural watersheds within the Lower Mississippi River Basin have greater hydrologic alteration compared to upland non-agricultural watersheds, particularly with declines in base flow and an increase in extreme low flows. Long-term streamflow records from USGS gauges located in predominantly agricultural and non-agricultural watersheds in Arkansas, Louisiana, Mississippi, and Tennessee were evaluated from 1969 -2016 using the Indicators of Hydrologic Alteration (IHA) software. Preliminary results from 8 non-agricultural and 5 agricultural watersheds demonstrate a substantial decline in base flow in the agricultural watersheds, which is not apparent in the non-agricultural watersheds. This exploratory study will analyze the trade-off between gains in agricultural productivity and changes in ecohydrological indicators over the last half century in diverse watersheds across the Lower Mississippi River Basin. By quantifying the changes in ecosystem services provided by flowing waters in the past, we can inform sustainable management pathways to better balance services in the future.

River response to variations of periglacial climate in mid-latitude Europe.

NARCIS (Netherlands)

Mol, J.; Vandenberghe, J.; Kasse, C.

2000-01-01

The Last Glaciation was characterised by considerable changes in climate. Many European river basins reacted to these changes by initial incision and subsequent pattern change. Earlier research explained this by the time lag of vegetation development after a climatic change, which considerably

Suspended-sediment transport from the Green-Duwamish River to the Lower Duwamish Waterway, Seattle, Washington, 2013–17

Science.gov (United States)

Senter, Craig A.; Conn, Kathleen E.; Black, Robert W.; Peterson, Norman; Vanderpool-Kimura, Ann M.; Foreman, James R.

2018-02-28

The Green-Duwamish River transports watershed-derived sediment to the Lower Duwamish Waterway Superfund site near Seattle, Washington. Understanding the amount of sediment transported by the river is essential to the bed sediment cleanup process. Turbidity, discharge, suspended-sediment concentration (SSC), and particle-size data were collected by the U.S. Geological Survey (USGS) from February 2013 to January 2017 at the Duwamish River, Washington, within the tidal influence at river kilometer 16.7 (USGS streamgage 12113390; Duwamish River at Golf Course at Tukwila, WA). This report quantifies the timing and magnitude of suspended-sediment transported in the Duwamish River. Regression models were developed between SSC and turbidity and SSC and discharge to estimate 15- minute SSC. Suspended-sediment loads were calculated from the computed SSC and time-series discharge data for every 15-minute interval during the study period. The 2014–16 average annual suspended-sediment load computed was 117,246 tons (106,364 metric tons), of which 73.5 percent or (86,191 tons; 78,191 metric tons) was fine particle (less than 0.0625 millimeter in diameter) suspended sediment. The seasonality of this site is apparent when you divide the year into "wet" (October 16– April 15) and "dry" (April 16–October 15) seasons. Most (97 percent) of the annual suspended sediment was transported during the wet season, when brief periods of intense precipitation from storms, large releases from the Howard Hanson Dam, or a combination of both were much more frequent.

Characteristics of radium isotopes in the middle and lower reaches of the Yangtze river

International Nuclear Information System (INIS)

Su Ni; Du Jinzhou; Duan Zonglian

2010-01-01

The paper studied the distribution pattern of radium isotopes in the middle and lower reaches of the Yangtze River based on the cruise survey in Jan. 2008. The results showed that dissolved 226 Ra and 228 Ra activities varied stably around 1.17-2.37 Bq/m 3 and 1.47-3.28 Bq/m 3 in the middle reaches, while they increased in the lower reaches. Dissolved Ra activities were much higher in the Dongting and the Poyang Lakes. The particulate Ra activity was found to increase downstream. Additionally, the yearly flux of dissolved Ra from the river to the ocean was estimated based on the monthly measured Ra activity in the Xuliujing and the runoff. The estimated flux varied between 0.74 x 10 12 -1.96 x 10 12 Bq/y. The dissolved Ra activity was found largest in the Yangtze estuary, medium in the Yangtze River, and smallest in the East China Sea. It indicated the filter effect of the Yangtze estuary to the fate of terrestrial Ra. (authors)

Chemical concentrations in water and suspended sediment, Green River to Lower Duwamish Waterway near Seattle, Washington, 2016–17

Science.gov (United States)

Conn, Kathleen E.; Black, Robert W.; Peterson, Norman T.; Senter, Craig A.; Chapman, Elena A.

2018-01-05

From August 2016 to March 2017, the U.S. Geological Survey (USGS) collected representative samples of filtered and unfiltered water and suspended sediment (including the colloidal fraction) at USGS streamgage 12113390 (Duwamish River at Golf Course, at Tukwila, Washington) during 13 periods of differing flow conditions. Samples were analyzed by Washington-State-accredited laboratories for a large suite of compounds, including metals, dioxins/furans, semivolatile compounds including polycyclic aromatic hydrocarbons, butyltins, the 209 polychlorinated biphenyl (PCB) congeners, and total and dissolved organic carbon. Concurrent with the chemistry sampling, water-quality field parameters were measured, and representative water samples were collected and analyzed for river suspended-sediment concentration and particle-size distribution. The results provide new data that can be used to estimate sediment and chemical loads transported by the Green River to the Lower Duwamish Waterway.

Proposed modifications to the Lower Mokelumne River Project, California: FERC Project No. 2916-004. Final environmental impact statement

Energy Technology Data Exchange (ETDEWEB)

1993-11-01

This final environmental impact statement (FEIS) has been prepared for the Federal Energy Regulatory Commission (Commission) to consider modifications to the existing Lower Mokelumne River Project (LMRP) (FERC Project No. 2916-004) in California. Chinook salmon and steelhead trout populations in the lower Mokelumne River have experienced recent declines and fish kills associated, in part, with discharges from Camanche Dam. The California Department of Fish and Game and the California Sportfishing Protection Alliance have asked the Commission to investigate and correct these problems. A wide range of different mitigation actions has been proposed by parties participating in the scoping of this proceeding, and staff has evaluated these proposed actions in this assessment. The staff is recommending a combination of flow and non-flow modifications to the existing license, including new minimum flow and minimum pool elevation requirements at Camanche Reservoir, ramping rates on dam releases, interim attraction and out-migrant spike flows, instream habitat improvements, and a series of studies and monitoring to determine feasible means for solving off-site fish passage problems.

Migratory Behavior and Survival of Juvenile Salmonids in the Lower Columbia River, Estuary, and Plume in 2010

Energy Technology Data Exchange (ETDEWEB)

McMichael, Geoffrey A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Harnish, Ryan A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Skalski, John R. [Univ. of Washington, Seattle, WA (United States); Deters, Katherine A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ham, Kenneth D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Townsend, Richard L. [Univ. of Washington, Seattle, WA (United States); Titzler, P. Scott [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hughes, Michael S. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kim, Jin A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Trott, Donna M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2011-09-01

Uncertainty regarding the migratory behavior and survival of juvenile salmonids passing through the lower Columbia River and estuary after negotiating dams on the Federal Columbia River Power System (FCRPS) prompted the development and application of the Juvenile Salmon Acoustic Telemetry System (JSATS). The JSATS has been used to investigate the survival of juvenile salmonid smolts between Bonneville Dam (river kilometer (rkm) 236) and the mouth of the Columbia River annually since 2004. In 2010, a total of 12,214 juvenile salmonids were implanted with both a passive integrated transponder (PIT) and a JSATS acoustic transmitter. Using detection information from JSATS receiver arrays deployed on dams and in the river, estuary, and plume, the survival probability of yearling Chinook salmon and steelhead smolts tagged at John Day Dam was estimated form multiple reaches between rkm 153 and 8.3 during the spring. During summer, the survival probability of subyearling Chinook salmon was estimated for the same reaches. In addition, the influence of routes of passage (e.g., surface spill, deep spill, turbine, juvenile bypass system) through the lower three dams on the Columbia River (John Day, The Dalles, and Bonneville) on juvenile salmonid smolt survival probability from the dams to rkm 153 and then between rkm 153 and 8.3 was examined to increase understanding of the immediate and latent effects of dam passage on juvenile salmon survival. Similar to previous findings, survival probability was relatively high (>0.95) for most groups of juvenile salmonids from the Bonneville Dam tailrace to about rkm 50. Downstream of rkm 50 the survival probability of all species and run types we examined decreased markedly. Steelhead smolts suffered the highest mortality in this lower portion of the Columbia River estuary, with only an estimated 60% of the tagged fish surviving to the mouth of the river. In contrast, yearling and subyearling Chinook salmon smolts survived to the mouth

Evaluating Cumulative Ecosystem Response to Restoration Projects in the Lower Columbia River and Estuary, 2009

Energy Technology Data Exchange (ETDEWEB)

Johnson, Gary E.; Diefenderfer, Heida L.; Borde, Amy B.; Bryson, Amanda J.; Cameron, April; Coleman, Andre M.; Corbett, C.; Dawley, Earl M.; Ebberts, Blaine D.; Kauffman, Ronald; Roegner, G. Curtis; Russell, Micah T.; Silva, April; Skalski, John R.; Thom, Ronald M.; Vavrinec, John; Woodruff, Dana L.; Zimmerman, Shon A.

2010-10-26

This is the sixth annual report of a seven-year project (2004 through 2010) to evaluate the cumulative effects of habitat restoration actions in the lower Columbia River and estuary (LCRE). The project, called the Cumulative Effects Study, is being conducted for the U.S. Army Corps of Engineers Portland District (USACE) by the Marine Sciences Laboratory of the Pacific Northwest National Laboratory (PNNL), the Pt. Adams Biological Field Station of the National Marine Fisheries Service (NMFS), the Columbia River Estuary Study Taskforce (CREST), and the University of Washington. The goal of the Cumulative Effects Study is to develop a methodology to evaluate the cumulative effects of multiple habitat restoration projects intended to benefit ecosystems supporting juvenile salmonids in the 235-km-long LCRE. Literature review in 2004 revealed no existing methods for such an evaluation and suggested that cumulative effects could be additive or synergistic. From 2005 through 2009, annual field research involved intensive, comparative studies paired by habitat type (tidal swamp versus marsh), trajectory (restoration versus reference site), and restoration action (tidegate replacement vs. culvert replacement vs. dike breach).

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix E: Existing Systems and Major System Improvements Engineering

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

75 FR 6020 - Electrical Interconnection of the Lower Snake River Wind Energy Project

Science.gov (United States)

2010-02-05

... DEPARTMENT OF ENERGY Bonneville Power Administration Electrical Interconnection of the Lower Snake River Wind Energy Project AGENCY: Bonneville Power Administration (BPA), Department of Energy (DOE... (BPA) has decided to offer Puget Sound Energy Inc., a Large Generator Interconnection Agreement for...

Effects of flood control and other reservoir operations on the water quality of the lower Roanoke River, North Carolina

Science.gov (United States)

Garcia, Ana Maria

2012-01-01

The Roanoke River is an important natural resource for North Carolina, Virginia, and the Nation. Flood plains of the lower Roanoke River, which extend from Roanoke Rapids Dam to Batchelor Bay near Albemarle Sound, support a large and diverse population of nesting birds, waterfowl, freshwater and anadromous fish, and other wildlife, including threatened and endangered species. The flow regime of the lower Roanoke River is affected by a number of factors, including flood-management operations at the upstream John H. Kerr Dam and Reservoir. A three-dimensional, numerical water-quality model was developed to explore links between upstream flows and downstream water quality, specifically in-stream dissolved-oxygen dynamics. Calibration of the hydrodynamics and dissolved-oxygen concentrations emphasized the effect that flood-plain drainage has on water and oxygen levels, especially at locations more than 40 kilometers away from the Roanoke Rapids Dam. Model hydrodynamics were calibrated at three locations on the lower Roanoke River, yielding coefficients of determination between 0.5 and 0.9. Dissolved-oxygen concentrations were calibrated at the same sites, and coefficients of determination ranged between 0.6 and 0.8. The model has been used to quantify relations among river flow, flood-plain water level, and in-stream dissolved-oxygen concentrations in support of management of operations of the John H. Kerr Dam, which affects overall flows in the lower Roanoke River. Scenarios have been developed to mitigate the negative effects that timing, duration, and extent of flood-plain inundation may have on vegetation, wildlife, and fisheries in the lower Roanoke River corridor. Under specific scenarios, the model predicted that mean dissolved-oxygen concentrations could be increased by 15 percent by flow-release schedules that minimize the drainage of anoxic flood-plain waters. The model provides a tool for water-quality managers that can help identify options that improve

Hans Raj Negi

Indian Academy of Sciences (India)

Home; Journals; Resonance – Journal of Science Education. Hans Raj Negi. Articles written in Resonance – Journal of Science Education. Volume 8 Issue 1 January 2003 pp 51-58 General Article. Lichens: A Valuable Bioresource for Environmental Monitoring and Sustainable Development · Hans Raj Negi · More Details ...

Spatial and temporal trends in PCBs in sediment along the lower Rhone River, France

Energy Technology Data Exchange (ETDEWEB)

Desmet, Marc, E-mail: marc.desmet@univ-tours.fr [EA 6293 GeHCO Universite Francois-Rabelais de Tours, Parc de Grandmont, 37200 Tours (France); Mourier, Brice, E-mail: brice.mourier@entpe.fr [Universite Lyon 1, UMR 5023 Ecologie des Hydrosystemes Naturels et Anthropises, ENTPE, CNRS, 3, Rue Maurice Audin, 69518 Vaulx-en-Velin (France); Mahler, Barbara J., E-mail: bjmahler@usgs.gov [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Van Metre, Peter C., E-mail: pcvanmet@usgs.gov [U.S. Geological Survey, 1505 Ferguson Lane, Austin, TX 78754 (United States); Roux, Gwenaeelle, E-mail: gwenaelle.roux@entpe.fr [Universite Lyon 1, UMR 5023 Ecologie des Hydrosystemes Naturels et Anthropises, ENTPE, CNRS, 3, Rue Maurice Audin, 69518 Vaulx-en-Velin (France); Persat, Henri, E-mail: persat@biomserv.univ-lyon1.fr [Universite de Lyon, UMR 5023 Ecologie des Hydrosystemes Naturels et Anthropises, Universite Lyon 1, ENTPE, CNRS, 5 rue Raphaeel Dubois, 69221 Villeurbanne (France); Lefevre, Irene, E-mail: Irene.Lefevre@lsce.ipsl.fr [UMR 8212, LSCE, Bat. 12, avenue de la Terrasse, F-91198 Gif-sur-Yvette Cedex (France); Peretti, Annie, E-mail: royannie@gmail.com [Irstea, UR MALY, 3 bis Quai Chauveau, CP220, F-69336 Lyon (France); and others

2012-09-01

Despite increasingly strict control of polychlorinated biphenyl (PCB) releases in France since the mid-1970s, PCB contamination of fish recently has emerged as a major concern in the lower Rhone River basin. We measured PCB concentrations in Rhone sediment to evaluate the effects of PCB releases from major urban and industrial areas, sediment redistribution by large floods, and regulatory controls on PCB trends from 1970 to present. Profiles of PCBs (the sum of seven indicator PCB congeners) were reconstructed from sediment cores collected from an off-river rural reference site and from three depositional areas along the Rhone upstream and downstream from the city of Lyon, France. Core chronology was determined from radionuclide profiles and flood deposits. PCB concentrations increased progressively in the downstream direction, and reached a maximum concentration in 1991 of 281 {mu}g/kg at the most downstream site. At the rural reference site and at the upstream Rhone site, PCB concentrations peaked in the 1970s (maximum concentration of 13 and 78 {mu}g/kg, respectively) and have decreased exponentially since then. PCB concentrations in the middle and downstream cores were elevated into the early 1990s, decreased very rapidly until 2000, and since then have remained relatively stable. Congener profiles for three time windows (1965-80, 1986-93, and 2000-08) were similar in the three sediment cores from the Rhone and different from those at the rural reference site. The results indicate that permitted discharges from a hazardous-waste treatment facility upstream from Lyon might have contributed to high concentrations into the 1980-90s, but that industrial discharges from the greater Lyon area and tributaries to the Rhone near Lyon have had a greater contribution since the 1990s. There is little indication that PCB concentration in sediments downstream from Lyon will decrease over at least the short term. -- Highlights: Black-Right-Pointing-Pointer We reconstructed

2005 Puget Sound LiDAR Consortium (PSLC) Topographic LiDAR: Lower Columbia River

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Terrapoint, on behalf of multiple agencies, collected topographic lidar of the Lower Columbia River area. Field data collection took place between the dates of...

Estuary fish data - Juvenile salmon in migratory corridors of lower Columbia River estuary

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Sampling juvenile salmon and associated fishes in open waters of the lower Columbia River estuary. Field work includes bi-weekly sampling during the spring...

Hans Raj Wason

Indian Academy of Sciences (India)

Home; Journals; Journal of Earth System Science. Hans Raj Wason. Articles written in Journal of Earth System Science. Volume 125 Issue 4 June 2016 pp 855-871. Identification of seismically susceptible areas in western Himalaya using pattern recognition · Mridula Amita Sinvhal Hans Raj Wason · More Details Abstract ...

Rapid channel incision of the lower Pearl River (China since the 1990s as a consequence of sediment depletion

Directory of Open Access Journals (Sweden)

X. X. Lu

2007-12-01

Full Text Available This paper reported a dramatic channel incision (>10 m in the deepest cut during the past 10 y or so in the lower Pearl River, the second largest river in terms of water discharge in China. The channel incision had caused changes both in the channel geometry as well as in the river hydraulics. Also, the water exchange between the two major tributaries of the Pearl River, the Xijiang and Beijiang, had been significantly changed due to the channel incision. The rapid channel incision was principally the result of extensive sand mining in the lower Pearl River and the delta region due to the booming economy in the Pearl Delta region. Slight increase of water discharge and significant decrease of sediment load since the early 1990s in both the Xijiang and Beijiang also likely contributed to the observed dramatic river bed downcutting to some extent. This has important implications for river management, as the large Chinese rivers have seen a dramatic depletion of sediment fluxes due to the combined effects of declining rainfall, dam constructions, water diversion, reforestation and afforestation, and sediment mining over the recent decades.

Sand transport in the lower Mississippi River does not yield to dams: Applications for building deltaic land in Louisiana

Science.gov (United States)

Nittrouer, J. A.; Viparelli, E.

2013-12-01

The Mississippi Delta is presently undergoing a catastrophic drowning, whereby 5000 km2 of low-lying wetlands have converted to open water. This land loss is primarily the result of: a) relative sea-level rise, occurring due to the combined effect of rapid subsidence associated with subsurface fluids extraction and eustatic rise; b) leveeing and damming of the river and its tributaries, which restricts sediment delivery to and dispersal within the delta; and c) severe excavation of the delta for navigation channels. It has been argued that continued net land loss of the Mississippi Delta is inevitable due to declining measured total (sand and mud) suspended sediment loads over the past 6 decades. However, recent research has documented that the key to delta growth is deposition of sand, which accounts for ~50-70% of modern and ancient (up to 9 m.a.) Mississippi Delta deposits, but comprises only ~20% of the sampled portion of the total load. Here we present new analysis of existing data to show that sand transport has not diminished since dam construction. Furthermore, we produce a numerical model based on the mass balance of bed material loads over the lower 1600 km of the Mississippi River to show that mining of sand from the channel bed continues to replenish downstream sand loads. For example, our model results indicate that it requires approximately 240 years for a reduced sand load to reach the delta apex. Furthermore, our calculations indicate that sand load at the delta apex is reduced by a noticeable amount (17%) only after about 600 years. We also show how channel bed elevations are predicted to change over the lower 1600 km of the river channel due to channel mining. Channel-bed degradation is greatest at the upstream end of the study reach and decreases downstream. After 300 years the wave of significant degradation has just passed ~800 km downstream, or roughly half of our model domain. These results are in contrast to the measurements which concern

Effect of irrigation on soil salinity profiles along the Lower Vaal River ...

African Journals Online (AJOL)

The impact of long-term irrigation on semi-arid soils along the Lower Vaal River in central South Africa was assessed. Irrigated sandy and clayey soils representative of relatively homogeneous agro-ecosystems were sampled at 200 mm intervals to a depth of 2 m wherever possible. To serve as a reference, adjacent virgin ...

Quantitative Analysis and Comparison of BMI among Han, Tibetan, and Uygur University Students in Northwest China

Directory of Open Access Journals (Sweden)

Bai Jingya

2013-01-01

Full Text Available Objectives. To fully analyze and compare BMI among Han, Tibetan, and Uygur university students, to discuss the differences in their physical properties and physical health, and thus to provide some theoretical suggestions for the improvement of students’ physical health. Methods. The cross-sectional random cluster sampling was used to investigate 10103 Han, Tibetan, and Uygur university students, aged 20–24 in Northwest China, and their height and weight were measured to calculate BMI. The BMI classification criteria for Chinese established by Work Group on Obesity in China (WGOC were used for screening. Results. Han, Tibetan, and Uygur university students show low obesity rates but high overweight rates. Han, Tibetan, and Uygur university students present a high rate of underweight, normal weight, and overweight, respectively. Female Han students show higher underweight and normal weight rates, but lower overweight and obesity rates, than male Han students. Female Tibetan students show higher normal weight rate, but lower overweight and obesity rates, than male Tibetan students. BMI increases with age for male students but decreases with age for female students. Male Uygur students show higher obesity rate than female Uygur students. Tibetan and Uygur university students have higher BMI than other minorities in South China.

Quantitative Analysis and Comparison of BMI among Han, Tibetan, and Uygur University Students in Northwest China

Science.gov (United States)

Jingya, Bai; Ye, He; Jing, Wang; Xi, Huanjiu; Tao, Hai

2013-01-01

Objectives. To fully analyze and compare BMI among Han, Tibetan, and Uygur university students, to discuss the differences in their physical properties and physical health, and thus to provide some theoretical suggestions for the improvement of students' physical health. Methods. The cross-sectional random cluster sampling was used to investigate 10103 Han, Tibetan, and Uygur university students, aged 20–24 in Northwest China, and their height and weight were measured to calculate BMI. The BMI classification criteria for Chinese established by Work Group on Obesity in China (WGOC) were used for screening. Results. Han, Tibetan, and Uygur university students show low obesity rates but high overweight rates. Han, Tibetan, and Uygur university students present a high rate of underweight, normal weight, and overweight, respectively. Female Han students show higher underweight and normal weight rates, but lower overweight and obesity rates, than male Han students. Female Tibetan students show higher normal weight rate, but lower overweight and obesity rates, than male Tibetan students. BMI increases with age for male students but decreases with age for female students. Male Uygur students show higher obesity rate than female Uygur students. Tibetan and Uygur university students have higher BMI than other minorities in South China. PMID:24453807

Characterization of subsurface stratigraphy along the lower American River floodplain using electrical resistivity, Sacramento, California, 2011

Science.gov (United States)

Burton, Bethany L.; Powers, Michael H.; Ball, Lyndsay B.

2014-01-01

In July 2011, the U.S. Geological Survey, in cooperation with the U.S. Army Corps of Engineers, completed a geophysical survey using electrical resistivity along an approximately 6-mile reach of the lower American River in Sacramento, California, to map near-surface lithological variations. This survey is a part of a manifold and comprehensive study of river-flow dynamics and geologic boundary-property knowledge necessary to estimate scour potential and levee erosion risk. Data were acquired on the left (south or west) bank between river mile 5 and 10.7 as well as a short section on the right bank from river mile 5.4 to 6. Thirteen direct-current resistivity profiles and approximately 8.3 miles of capacitively coupled resisistivity data were acquired along accessible areas of the floodplain between the levee and river bank. Capacitively coupled resistivity was used as a reconnaissance tool, because it allowed for greater spatial coverage of data but with lower resolution and depth of investigation than the DC resistivity method. The study area contains Pleistocene-age alluvial deposits, dominated by gravels, sands, silts, and clays, that vary in both lateral extent and depth. Several generations of lithologic logs were used to help interpret resistivity variations observed in the resistivity models.

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007

Energy Technology Data Exchange (ETDEWEB)

Sobocinski, Kathryn L.; Johnson, Gary E.; Sather, Nichole K.; Storch, Adam; Jones, Tucker A.; Mallette, Christine; Dawley, Earl M.; Skalski, John R.; Teel, David; Moran, Paul

2008-03-18

This document is the first annual report for the study titled “Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River.” Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council’s Columbia Basin Fish and Wildlife Program.

Spatial Pattern of Populus euphratica Forest Change as Affected by Water Conveyance in the Lower Tarim River

Directory of Open Access Journals (Sweden)

Shuhong Peng

2014-01-01

Full Text Available To restore declining species, including Populus euphratica and other riparian communities, in the river ecosystem of the lower Tarim River, the ecological water conveyance project (EWCP, as a part of an integrated water resource management plan, was implemented in 2000. The EWCP aims to schedule and manage the water resources in the upper reaches and transfer water to the lower reaches by a series of intermittent water deliveries. The delivered water flows along a modified river channel and nourishes riparian communities by river overflow flooding. Since it began, it has caused a fierce debate over the response of riparian vegetation to the water conveyance scheme. This study focuses on the lower Tarim River, where Populus euphratica forests have undergone watering, due to the EWCP. Twelve Landsat sensor images and one IKONOS satellite imagery acquired between 1999 and 2009 were used to monitor the change in Populus euphratica forests. Bi-temporal change detection and temporal trajectory analysis were employed to represent the spatial pattern of the forest change. Field investigations were used to analyze the driving forces behind forest change from the perspectives of anthropogenic activities and natural forces. The results showed that Populus euphratica forest have been declining in area, which implies that ecological risks have been increased during the watering process. However, forests areas have increased in the regions where the water supply is abundant, and vice versa.

Managing Floodplain Expectations on the Lower Missouri River, USA.

Science.gov (United States)

Bulliner, E. A., IV; Jacobson, R. B.; Lindner, G. A.; Paukert, C.; Bouska, K.

2017-12-01

The Missouri River is an archetype of the challenges of managing large rivers and their floodplains for multiple objectives. At 1.3 million km2 drainage area, the Missouri boasts the largest reservoir system in North America with 91 km3 of total storage; in an average year the system generates 10 billion kilowatt hours of electricity. The Lower Missouri River floodplain extends 1,300 km downstream from the reservoir system and encompasses approximately 9,200 km2. For the past 150 years, the floodplain has been predominantly used for agriculture much of which is protected from flooding by private and Federal levees. Reservoir system operating policies prioritize flood-hazard reduction but in recent years, large, damaging floods have demonstrated system limitations. These large floods and changing societal values have created new expectations about how conversion of floodplain agricultural lands to conservation lands might increase ecosystem services, in particular decreasing flood risk and mitigating fluxes of nutrients to the Gulf of Mexico. Our research addresses these expectations at multiple spatial scales by starting with hydrologic and hydraulic models to understand controls on floodplain hydrodynamics. The results document the substantial regional spatial variability in floodplain connectivity that exists because of multi-decadal channel adjustments to channelization and sediment budgets. Exploration of levee setback scenarios with 1- and 2-dimensional hydrodynamic models indicates modest and spatially variable gains in flood-hazard reduction are possible if substantial land areas (50% or more) are converted from agricultural production. Estimates of potential denitrification benefits of connecting floodplains indicate that the floodplain has the capacity to remove 100's to 1,000's of metric tons of N each year, but amounts to a maximum of about 5% the existing load of 200,000 ton*y-1. The results indicate that in this river-floodplain system, the ecosystem

Ground water flow velocity in the bank of the Columbia River, Hanford, Washington

International Nuclear Information System (INIS)

Ballard, S.

1995-12-01

To properly characterize the transport of contaminants from the sediments beneath the Hanford Site into the Columbia River, a suite of In Situ Permeable Flow Sensors was deployed to accurately characterize the hydrologic regime in the banks of the river. The three dimensional flow velocity was recorded on an hourly basis from mid May to mid July, 1994 and for one week in September. The first data collection interval coincided with the seasonal high water level in the river while the second interval reflected conditions during relatively low seasonal river stage. Two flow sensors located approximately 50 feet from the river recorded flow directions which correlated very well with river stage, both on seasonal and diurnal time scales. During time intervals characterized by falling river stage, the flow sensors recorded flow toward the river while flow away from the river was recorded during times of rising river stage. The flow sensor near the river in the Hanford Formation recorded a component of flow oriented vertically downward, probably reflecting the details of the hydrostratigraphy in close proximity to the probe. The flow sensor near the river in the Ringold Formation recorded an upward component of flow which dominated the horizontal components most of the time. The upward flow in the Ringold probably reflects regional groundwater flow into the river. The magnitudes of the flow velocities recorded by the flow sensors were lower than expected, probably as a result of drilling induced disturbance of the hydraulic properties of the sediments around the probes. The probes were installed with resonant sonic drilling which may have compacted the sediments immediately surrounding the probes, thereby reducing the hydraulic conductivity adjacent to the probes and diverting the groundwater flow away from the sensors

Soil of the lower valley of the Dragonja river (Slovenia)

OpenAIRE

Tomaž PRUS; Nina ZUPANČIČ; Helena GRČMAN

2015-01-01

Soil of the lower valley of the river Dragonja developed under specific soil-forming factors. Soil development in the area was influenced by alluvial sediments originating from surrounding hills, mostly of flysch sequence rocks, as a parent material, Sub-Mediterranean climate and the vicinity of the sea. Different soil classification units (Gleysol and Fluvisol) were proposed for that soil in previous researches. The aim of our study was the evaluation of morphological, chemical and mineralog...

HISTORICAL FLOOD RISK MANAGEMENT: SPATIAL EXPANSION OF GHERGHIȚA VILLAGE (LOWER PRAHOVA RIVER

Directory of Open Access Journals (Sweden)

IOANA-TOROIMAC GABRIELA

2015-03-01

Full Text Available This paper analyses settlements expansion in flood zones during historical time. We focused on the example of Gherghiţa village on Lower Prahova River by using a diachronic study in GIS. It revealed three major periods of extension of Gherghița village and flood risk management: (1 from Middle Age to the end of the 19th century – prevention against floods by expansion outside the flood-prone area; (2 during the major part of the 20th – flood negligence by expansion inside the flood-prone area; (3 at the end of the 20th century and at the beginning of the 21th century – protection against floods by extension inside the flood-prone area with structural measures (i.e. levees. As a consequence, human pressure on Lower Prahova River grew since the beginning of the 20th century, especially for agricultural purposes.

Mapping groundwater availability and adequacy in the Lower Zambezi River basin

Directory of Open Access Journals (Sweden)

B. Pérez-Lapeña

2018-05-01

Full Text Available Groundwater plays an important role as a source of water for various socio-economic uses and environmental requirements in the lower Zambezi basin in Mozambique. Hence it is important to know its availability and adequacy in space to inform decision making for sustainable water management practices. For a derivation of a Groundwater Availability map and a Groundwater Adequacy map we adapted the DRASTIC methodology in a GIS environment to determine how different parameters, such as precipitation, topography, soil drainage, land use and vegetation cover, aquifer characteristics and groundwater quality affect (i groundwater recharge on a long-term sustainable basis, (ii the short-term abstraction potential and (iii the long-term adequacy of groundwater utilization for domestic use. Results showed that groundwater availability in the Zambezi basin varies mostly from medium to low, with highest potential along the perennial rivers and in the delta where it plays a crucial role in environmental preservation. The southern margin of the Zambezi River shows low groundwater availability and also presents low adequacy for domestic use due to poor groundwater quality. The results from this study will be used in determining the most promising future development pathways and select the most attractive strategic development plans of the Mozambican government for the Lower Zambezi basin.

Sedimentation Impacts Modeling for the Lower Elwha River

Science.gov (United States)

Beggs, M.; Kosaka, M.; Sigel, A.; Vandermause, R.; Lauer, J. W.

2012-12-01

The removal of Glines Canyon and Elwha Dams from the Elwha River, northwest Washington, is intended to restore natural geomorphic and ecological processes to the Elwha River basin. Prior to the start of dam removal, over 16 million cubic meters of sediment had accumulated in the reservoirs above the two dams. As dam removal progresses, a portion of this sediment will erode and then be deposited on the downstream river bed and floodplain. To address uncertainty in downstream response to the project, the United States Bureau of Reclamation is implementing an adaptive management plan that relies upon continuous monitoring of water levels at a set of stream gages along the river. To interpret the monitoring data and allow for rapid assessment of the rate of downstream sedimentation, we developed rating curves at several locations along the lower Elwha River. The curves consider a range of possible sedimentation scenarios, each involving different sedimentation levels and/or locations. One scenario considers sedimentation primarily in the river channel, another considers sedimentation primarily on the floodplain, and a third considers both possibilities in tandem. We modeled these scenarios using two separate approaches. First, we modified the cross sections in an existing U.S. Army Corps of Engineers HEC-RAS model to represent possible changes associated with geomorphic adjustment to the dam removals. In-channel sedimentation was assumed to occur as a constant fraction of the bankfull depth at any given section, thereby focusing geomorphic change in relatively deep pool areas. In the HEC-RAS model, off-channel sedimentation was assumed uniform. The HEC-RAS model showed that both low-flow and flood hydraulics are much more sensitive to plausible levels of in-channel sedimentation than to plausible levels of overbank sedimentation. The wide floodplain, complex secondary channels, and geomorphic evolution since the original cross sections were surveyed raise some

Clay mineralogy and source-to-sink transport processes of Changjiang River sediments in the estuarine and inner shelf areas of the East China Sea

Science.gov (United States)

Zhao, Yifei; Zou, Xinqing; Gao, Jianhua; Wang, Chenglong; Li, Yali; Yao, Yulong; Zhao, Wancang; Xu, Min

2018-02-01

We examined the source-to-sink sediment transport processes from the Changjiang River to the estuarine coastal shelf area by analyzing the clay mineral assemblages in suspended sediment samples from the Changjiang River catchment and surface samples from the estuarine coastal shelf area following the impoundment of the Three Gorges Dam (TGD) in 2003. The results indicate that the clay mineral compositions throughout the study area are dominated by illite, with less abundant kaolinite and chlorite and scarce smectite. The clay minerals display distinct differences in the tributaries and exhibit obvious changes in the trunk stream compared with the periods before 2003, and the source of sediment has largely shifted to the mid- to lower reaches of the river after 2003. Spatially, the clay mineral assemblages in the estuarine area define two compositionally distinct provinces. Province I covers the mud area of the Changjiang River estuary and the Zhe-Min coastal region, where sediment is primarily supplied by the Changjiang River. Province II includes part of the Changjiang River estuary and the southeastern portion of the study area, where the sediment is composed of terrestrial material from the Changjiang River and re-suspended material from the Huanghe River carried by the Jiangsu coastal current. Moreover, the other smaller rivers in China (including the Oujiang and Minjiang rivers of mainland China and the rivers of West Taiwan) also contribut sediments to the estuarine and inner shelf areas. In general, the clay mineral assemblages in the Changjiang River estuarine area are have mainly been controlled by sediment supplied from upstream of the Changjiang River tributaries. However, since the completion of the TGD in 2003, the mid- to downstream tributaries have become the main source of sediments from the Changjiang catchment into the East China Sea. These analyses further demonstrate that the coastal currents and the decrease in the sediment load of the river

Estimates of Shear Stress and Measurements of Water Levels in the Lower Fox River near Green Bay, Wisconsin

Science.gov (United States)

Westenbroek, Stephen M.

2006-01-01

Turbulent shear stress in the boundary layer of a natural river system largely controls the deposition and resuspension of sediment, as well as the longevity and effectiveness of granular-material caps used to cover and isolate contaminated sediments. This report documents measurements and calculations made in order to estimate shear stress and shear velocity on the Lower Fox River, Wisconsin. Velocity profiles were generated using an acoustic Doppler current profiler (ADCP) mounted on a moored vessel. This method of data collection yielded 158 velocity profiles on the Lower Fox River between June 2003 and November 2004. Of these profiles, 109 were classified as valid and were used to estimate the bottom shear stress and velocity using log-profile and turbulent kinetic energy methods. Estimated shear stress ranged from 0.09 to 10.8 dynes per centimeter squared. Estimated coefficients of friction ranged from 0.001 to 0.025. This report describes both the field and data-analysis methods used to estimate shear-stress parameters for the Lower Fox River. Summaries of the estimated values for bottom shear stress, shear velocity, and coefficient of friction are presented. Confidence intervals about the shear-stress estimates are provided.

Coal rank, distribution, and coalbed methane potential of the Lower Cretaceous Luscar Group, Bow River to Blackstone River, central Alberta foothills

Energy Technology Data Exchange (ETDEWEB)

Dawson, F M; Kalkreuth, W D

1994-12-31

Mapping data on Lower Cretaceous Luscar Group coals in the central Alberta foothills is presented. The coals outcrop in the Inner Foothills from the Bow River to the boundary between Alberta and British Columbia, north of Grande Cache. Both subsurface and surface mapping data is presented. The coal rank is highly variable and depends on sample location and depth, as established by vitrinite reflectance studies on trench samples and cuttings gathered from petroleum exploration wells. The conventional coal resource potential and the coalbed methane potential for the area are discussed with reference to the map sheets provided. 29 refs., 45 figs., 3 tabs., 3 apps.

Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1998 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Everett, Scott R.; Tuell, Michael A. (Nez Perce Tribe, Department of Fisheries Resource Management, Lapwai, ID)

2002-03-01

In 1998 white sturgeon (Acipenser transmontanus) were captured, marked, and population data were collected in the Snake River between Lower Granite Dam and the mouth of the Salmon River. A total of 13,785 hours of setline effort and 389 hours of hook-and-line effort was employed in 1998. Of the 278 white sturgeon captured in the Snake River, 238 were marked for future identification. Three sturgeon were captured in the Salmon River and none were captured in the Clearwater River. Since 1997, 6.9% of the tagged fish have been recovered. Movement of recaptured white sturgeon ranged from 98.5 kilometers downstream to 60.7 kilometers upstream, however, less than 25% of the fish moved more than 16 kilometers (10 miles). In the Snake River, white sturgeon ranged in total length from 51.5 cm to 286 cm and averaged 118.9 cm. Differences were detected in the length frequency distributions of sturgeon in Lower Granite Reservoir and the free-flowing Snake River (Chi-Square test, P < 0.05). In addition, the proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River has shown an increase of 37% since the 1970's. Analysis of the length-weight relationship indicated that white sturgeon in Lower Granite Reservoir were slightly larger than white sturgeon in the free-flowing Snake River.

Bank Erosion, Mass Wasting, Water Clarity, Bathymetry and a Sediment Budget Along the Dam-Regulated Lower Roanoke River, North Carolina

Science.gov (United States)

Schenk, Edward R.; Hupp, Cliff R.; Richter, Jean M.; Kroes, Daniel E.

2010-01-01

Dam construction and its impact on downstream fluvial processes may substantially alter ambient bank stability, floodplain inundation patterns, and channel morphology. Most of the world's largest rivers have been dammed, which has prompted management efforts to mitigate dam effects. Three high dams (completed between 1953 and 1963) occur along the Piedmont portion of the Roanoke River, North Carolina; just downstream, the lower part of the river flows across largely unconsolidated Coastal Plain deposits. To document bank erosion rates along the lower Roanoke River, more than 700 bank erosion pins were installed along 124 bank transects. Additionally, discrete measurements of channel bathymetry, water clarity, and presence or absence of mass wasting were documented along the entire 153-kilometer-long study reach. Amounts of bank erosion in combination with prior estimates of floodplain deposition were used to develop a bank erosion and floodplain deposition sediment budget for the lower river. Present bank erosion rates are relatively high [mean 42 milimeters per year (mm/yr)] and are greatest along the middle reaches (mean 60 mm/yr) and on lower parts of the bank on all reaches. Erosion rates were likely higher along upstream reaches than present erosion rates such that erosion rate maxima have migrated downstream. Mass wasting and water clarity also peak along the middle reaches.

Evidence for a marine incursion along the lower Colorado River corridor

Science.gov (United States)

McDougall, Kristin; Martínez, Adriana Yanet Miranda

2014-01-01

Foraminiferal assemblages in the stratigraphically lower part of the Bouse Formation in the Blythe Basin indicate marine conditions whereas assemblages in the upper part of the Bouse Formation indicate lacustrine conditions and suggest the presence of a saline lake. Benthic foraminiferal assemblages in the lower part of the Bouse Formation are similar to lagoonal and inner neritic biofacies of the modern Gulf of California. Evidence suggesting a change from marine to lacustrine conditions includes the highest occurrence of planktic foraminifers at an elevation of 123 m asl, the change from low diversity to monospecific foraminiferal assemblages composed only of Ammonia beccarii (between 110 to126 m asl), an increase in abundance of A. beccarii specimens (above ~110 m asl), increased number of deformed tests (above ~123 m asl), first appearance of Chara (at ~85 m asl), lowest occurrence of reworked Cretaceous coccoliths (at ~110 m), a decrease in strontium isotopic values (between 70-120 m), and δ18O and δ13C values similar to sea water (between 70-100 m asl). Planktic foraminifers indicate a late Miocene age between 8.10 and 5.3 Ma for the oldest part of the Bouse Formation in the southern part of the Blythe Basin. Benthic and planktic foraminifers correlate with other late Miocene sections and suggest that the basal Bouse Formation in the Blythe Basin was deposited at the northern end of the proto-Gulf of California. After the marine connection was restricted or eliminated, the Colorado River flowed into the Blythe Basin forming a saline lake. This lake supported a monospecific foraminiferal assemblage of A. beccarii until the lake spilled into the Salton Trough and the Colorado River became a through-flowing river.

Distribution of the rare earth elements in the surface sediments from the lower Wuding River of China

International Nuclear Information System (INIS)

Longjiang, M.; Duowen, M.; Ke, H.; Jinghong, Y.

2010-01-01

The abundance and distribution of rare earth elements (REE) and their signatures in the Wuding River of China were studied from samples of surface sediments and related to the geological formation in its watershed. The total REE (ΣREE) average concentrations of the Wuding River sediments (144.56 μg g -1 ), is lower than that in the Yangtze River sediments (167.10 μg g -1 ), getting closer to the values of the Yellow River sediments (137.76 μg g -1 ), being equivalent to the values of the UCC (the upper continental crust) (146.37 μg g-1). The chondrite-normalized REEs indicated LREE enrichment and flat HREE depletion and also showed a slightly negative Eu-anomaly. A similar chondrite-normalized REE distribution pattern between the Wuding River sediments and Yellow River sediments demonstrated the Wuding River sediments are the important material sources of the Yellow River sediments. UCC-normalized REE patterns between the Wuding River sediments and the Yellow River sediments were almost equivalent and close to the UCC. These implied the Wuding River sediments and the Yellow River sediments are subjected mostly to physical weathering due to higher erosion rates. Consequently, they can be used to trace the UCC compositions. (author)

U isotopes distribution in the Lower Rhone River and its implication on radionuclides disequilibrium within the decay series.

Science.gov (United States)

Zebracki, Mathilde; Cagnat, Xavier; Gairoard, Stéphanie; Cariou, Nicolas; Eyrolle-Boyer, Frédérique; Boulet, Béatrice; Antonelli, Christelle

2017-11-01

The large rivers are main pathways for the delivery of suspended sediments into coastal environments, affecting the biogeochemical fluxes and the ecosystem functioning. The radionuclides from 238 U and 232 Th-series can be used to understand the dynamic processes affecting both catchment soil erosion and sediment delivery to oceans. Based on annual water discharge the Rhone River represents the largest river of the Mediterranean Sea. The Rhone valley also represents the largest concentration in nuclear power plants in Europe. A radioactive disequilibrium between particulate 226 Ra (p) and 238 U (p) was observed in the suspended sediment discharged by the Lower Rhone River (Eyrolle et al. 2012), and a fraction of particulate 234 Th was shown to derive from dissolved 238 U (d) (Zebracki et al. 2013). This extensive study has investigated the dissolved U isotopes distribution in the Lower Rhone River and its implication on particulate radionuclides disequilibrium within the decay series. The suspended sediment and filtered river waters were collected at low and high water discharges. During the 4-months of the study, two flood events generated by the Rhone southern tributaries were monitored. In river waters, the total U (d) concentration and U isotopes distribution were obtained through Q-ICP-MS measurements. The Lower Rhone River has displayed non-conservative U-behavior, and the variations in U (d) concentration between southern tributaries were related to the differences in bedrock lithology. The artificially occurring 236 U was detected in the Rhone River at low water discharges, and was attributed to the liquid releases from nuclear industries located along the river. The ( 235 U/ 238 U) (d) activity ratio (=AR) in river waters was representative of the 235 U natural abundance on Earth. The ( 226 Ra/ 238 U) (p) AR in suspended sediment has indicated a radioactive disequilibrium (average 1.3 ± 0.1). The excess of 234 Th in suspended sediment =( 234 Th xs

Re-Introduction of Lower Columbia River Chum Salmon into Duncan Creek, 2002-2003 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Hillson, Todd D. (Washington Department of Fish and Wildlife, Olympia, WA)

2003-10-15

The National Marine Fisheries Service (NMFS) listed Lower Columbia River chum as threatened under the auspices of the Endangered Species Act (ESA) in March of 1999 (64 FR 14508, March 25, 1999). The listing was in response to reduction in abundance from historical levels of more than half a million returning adults to fewer than 10,000 present day spawners. Harvest, loss of habitat, changes in flow regimes, riverbed movement and heavy siltation have been largely responsible for the decline of Columbia River chum salmon. The timing of seasonal changes in river flow and water temperatures is perhaps the most critical factor in structuring the freshwater life history of this species. This is especially true of the population located directly below Bonneville Dam where hydropower operations can block access to spawning sites, dewater redds, strand fry, cause scour or fill of redds and increase sedimentation of spawning gravels. Currently, only two main populations are recognized as genetically distinct in the Columbia River, although spawning has been documented in most lower Columbia River tributaries. The first is located in the Grays River (RKm 34) (Grays population), a tributary of the Columbia, and the second is a group of spawners that utilize the Columbia River just below Bonneville Dam (RKm 235) adjacent to Ives Island and in Hardy and Hamilton creeks (Lower Gorge population). A possible third population of mainstem spawners, found in the fall of 1999, were located spawning above the I-205 bridge (approximately RKm 182), this aggregation is referred to as the Woods Landing/Rivershore population or the I-205 group. The recovery strategy for Lower Columbia River (LCR) chum as outlined in Hatchery Genetic Management Plans (HGMP) has three main tasks. First, determine if remnant populations of LCR chum salmon exist in LCR tributaries. Second, if such populations exist, develop stock-specific recovery plans involving habitat restoration including the creation of

Environmental isotope-aided studies on river water and groundwater interaction in the region of Seoul and Taegu

International Nuclear Information System (INIS)

Jong Sung Ahn

1987-09-01

The report provides the results and evaluations of environmental isotope analyses (O-18, H-2, H-3) undertaken in detailed field investigations carried out in the Han River Basin to study the hydrodynamics of river water and groundwater interrelationships. The conducted study, particularly near the Seoul area and the Taegu area, has enabled the delineation of the origin of groundwater in crystalline rock aquifers and limestone aquifers of the Han River Basin and evaluations as regards the groundwater flow dynamics based on environmental isotope data are given in the report. Refs, figs, tabs

Gas Supersaturation May Reduce the Survival of Yearling Chinook Salmon in the Lower Columbia River and Ocean Plume

Science.gov (United States)

Brosnan, Ian; Welch, David; Scott, Melinda Jacobs

2015-01-01

Unusually high flows in the Columbia River in 2011 raised total dissolved gas (TDG) levels in the river above the 120 percent legal limit imposed to prevent harmful impacts to aquatic organisms. This provided a unique opportunity to evaluate the effect on smolt survival. In-river (IR) migrating juvenile yearling Chinook released at Bonneville Dam with acoustic tags during periods when TDG exceeded 120 percent received estimated maximum exposures of 134 TDG. Subsequent daily survival rates in the lower river and plume were reduced by 0.06 per day (SE equals 0.01) and 0.15 per day (SE equals 0.05) relative to IR migrant fish released when TDG was less than 120 percent. Transported smolts (T) released 10-13 kilometers below Bonneville Dam had lower maximum exposure levels (126 percent) and experienced no difference in daily survival rates relative to unexposed smolts. River temperature levels and trends in turbidity and disease prevalence between releases of high and low exposure smolts were not consistent with the observed effects on survival rates. We conclude that smolts may suffer from chronic effects of elevated TDG exposure while migrating through the Columbia River and plume. Consideration should be given to measuring these survival losses in an explicit experimental framework that isolates possible confounding factors.

Sedimentology and Palynostratigraphy of a Pliocene-Pleistocene (Piacenzian to Gelasian) deposit in the lower Negro River: Implications for the establishment of large rivers in Central Amazonia

Science.gov (United States)

Soares, Emílio Alberto Amaral; D'Apolito, Carlos; Jaramillo, Carlos; Harrington, Guy; Caputo, Mario Vicente; Barbosa, Rogério Oliveira; Bonora dos Santos, Eneas; Dino, Rodolfo; Gonçalves, Alexandra Dias

2017-11-01

The Amazonas fluvial system originates in the Andes and runs ca. 6700 km to the Atlantic Ocean, having as the main affluent the Negro River (second largest in water volume). The Amazonas transcontinental system has been dated to the late Miocene, but the timing of origin and evolutionary processes of its tributaries are still poorly understood. Negro River alluvial deposits have been dated to the middle to late Pleistocene. Recently, we studied a number of boreholes drilled for the building of a bridge at the lower course of the Negro River. A thin (centimetric) sedimentary deposit was found, laterally continuous for about 1800 m, unconformably overlaying middle Miocene strata and unconformably overlain by younger Quaternary deposits. This deposit consists predominantly of brownish-gray sandstones cemented by siderite and with subordinate mudstone and conglomerate beds. Palynological, granulometric, textural and mineralogical data suggest that the initial Negro River aggradation took place in the deep incised valley under anoxic conditions and subsequently along the floodplain, with efficient transport of mixed origin particles (Andean and Amazonic). Angiosperm leaves, wood and pollen are indicative of a tropical continental palaeoenvironment. A well preserved palynoflora that includes Alnipollenites verus, Grimsdalea magnaclavata and Paleosantalaceaepites cingulatus suggests a late Pliocene to early Pleistocene (Piacenzian to Gelasian) age for this unit, which was an age yet unrecorded in the Amazon Basin. These results indicate that by the late Pliocene-early Pleistocene, large scale river activity was occurring in Central Amazonia linking this region with the Andean headwaters, and therefore incompatible with Central Amazonia barriers like the Purus arch.

High frequency measurement of nitrate concentration in the Lower Mississippi River, USA

Science.gov (United States)

Duan, Shuiwang; Powell, Rodney T.; Bianchi, Thomas S.

2014-11-01

Nutrient concentrations in the Mississippi River have increased dramatically since the 1950s, and high frequency measurements on nitrate concentration are required for accurate load estimations and examinations on nitrate transport and transformation processes. This three year record of high temporal resolution (every 2-3 h) data clearly illustrates the importance of high frequency sampling in improving load estimates and resolving variations in nitrate concentration with river flow and tributary inputs. Our results showed large short-term (days to weeks) variations in nitrate concentration but with no diurnal patterns. A repeatable and pronounced seasonal pattern of nitrate concentration was observed, and showed gradual increases from the lowest values in September (during base-flow), to the highest in June - which was followed by a rapid decrease. This seasonal pattern was only moderately linked with water discharge, and more controlled by nitrogen transformation/export from watershed as well as mixing patterns of the two primary tributaries (the upper Mississippi and the Ohio Rivers), which have distinctly different nitrate concentrations and flow patterns. Based on continuous in situ flow measurements, we estimated 554-886 × 106 kg of nitrate-N was exported from the Mississippi River system during years 2004-2006, which was <9% and <16% lower than U.S. Geological Survey's (USGS) estimates using their LOADEST or composite methods, respectively. USGS methods generally overestimated nitrate loads during rising stages and underestimated the loads during falling stages. While changes in nitrate concentrations in large rivers are generally not as responsive to alterations in diurnal inputs and/or watershed hydrology as small rivers, high-frequency water quality sampling would help in monitoring short-term (days to weeks) variations in nutrient concentration patterns and thus improve the accuracy of nutrient flux estimates.

An ecological economic assessment of flow regimes in a hydropower dominated river basin: the case of the lower Zambezi River, Mozambique.

Science.gov (United States)

Fanaian, Safa; Graas, Susan; Jiang, Yong; van der Zaag, Pieter

2015-02-01

The flow regime of rivers, being an integral part of aquatic ecosystems, provides many important services benefiting humans in catchments. Past water resource developments characterized by river embankments and dams, however, were often dominated by one (or few) economic use(s) of water. This results in a dramatically changed flow regime negatively affecting the provision of other ecosystem services sustained by the river flow. This study is intended to demonstrate the value of alternative flow regimes in a river that is highly modified by the presence of large hydropower dams and reservoirs, explicitly accounting for a broad range of flow-dependent ecosystem services. In this study, we propose a holistic approach for conducting an ecological economic assessment of a river's flow regime. This integrates recent advances in the conceptualization and classification of ecosystem services (UK NEA, 2011) with the flow regime evaluation technique developed by Korsgaard (2006). This integrated approach allows for a systematic comparison of the economic values of alternative flow regimes, including those that are considered beneficial for aquatic ecosystems. As an illustration, we applied this combined approach to the Lower Zambezi Basin, Mozambique. Empirical analysis shows that even though re-operating dams to create environmentally friendly flow regimes reduces hydropower benefits, the gains to goods derived from the aquatic ecosystem may offset the forgone hydropower benefits, thereby increasing the total economic value of river flow to society. The proposed integrated flow assessment approach can be a useful tool for welfare-improving decision-making in managing river basins. Copyright © 2014 Elsevier B.V. All rights reserved.

Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2000 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Everett, Scott R.; Tuell, Michael A. (Nez Perce Tribe, Department of Fishereis Resource Management, Lapwai, ID)

2003-03-01

The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 2000 annual report covers the fourth year of sampling of this multi-year study. In 2000 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon rivers. The Snake River was sampled between Lower Granite Dam (rkm 174) and the mouth of the Salmon River (rkm 303), and the Salmon River was sampled from its mouth upstream to Hammer Creek (rkm 84). A total of 53,277 hours of setline effort and 630 hours of hook-and-line effort was employed in 2000. A total of 538 white sturgeon were captured and tagged in the Snake River and 25 in the Salmon River. Since 1997, 32.8 percent of the tagged white sturgeon have been recaptured. In the Snake River, white sturgeon ranged in total length from 48 cm to 271 cm and averaged 107 cm. In the Salmon River, white sturgeon ranged in total length from 103 cm to 227 cm and averaged 163 cm. Using the Jolly-Seber open population estimator, the abundance of white sturgeon <60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 2,725 fish, with a 95% confidence interval of 1,668-5,783. A total of 10 white sturgeon were fitted with radio-tags. The movement of these fish ranged from 54.7 km (34 miles) downstream to 78.8 km (49 miles) upstream; however, 43.6 percent of the detected movement was less than 0.8 km (0.5 mile). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No seasonal movement pattern was detected, and no movement pattern was detected for different size fish. Differences were detected in the length frequency distributions of

Human impacts on runoff regime of middle and lower Yellow River

Directory of Open Access Journals (Sweden)

Yan-fang Sang

2011-03-01

Full Text Available In this study, the 54-year (1950 to 2003 monthly runoff series from February, April, August, and November, as well as the annual runoff series, measured at both Huayuankou and Lijin hydrological stations were chosen as representative data, and the continuous wavelet transform (CWT was applied to analyze the impacts of human activities on the runoff regime of the middle and lower Yellow River. A point of change in 1970 was first determined, and the observed series before 1970 were considered natural runoff while those after 1970 were restored according to linear trends. Then, the CWT was applied to both the observed and restored runoff series to reveal their variations at multi-temporal scales, including the five temporal ranges of 1–4, 6–8, 9–12, 16–22, and 22–30 years, and the trend at the temporal scale of 54 years. These analysis results are compared and discussed in detail. In conclusion, because of the impacts of human activities, there have been significant changes in the runoff regime in the middle and lower Yellow River since 1970. The decaying tendency of annual runoff has become more pronounced, and the inner-annual distribution of runoff has changed, but human activities have had little impact on the periodic characteristics of runoff.

Avian predation on juvenile salmonids in the Lower Columbia River; 1998 annual report

International Nuclear Information System (INIS)

Collis, Ken; Adamany, Stephanie; Roby, Daniel D.; Craig, David P.; Lyons, Donald E.

2000-01-01

The authors initiated a field study in 1997 to assess the impacts of fish-eating colonial waterbirds (i.e., terns, cormorants, and gulls) on the survival of juvenile salmonids in the lower Columbia River. Here the authors present results from the 1998 breeding season, the second field season of work on this project. The research objectives in 1998 were to: (1) determine the location, size, nesting chronology, nesting success, and population trajectories of breeding colonies of fish-eating birds in the lower Columbia River; (2) determine diet composition of fish-eating birds, including taxonomic composition and energy content of various prey types; (3) estimate forage fish consumption rates, with special emphasis on juvenile salmonids, by breeding adults and their young; (4) determine the relative vulnerability of different groups of juvenile salmonids to bird predation; (5) identify foraging range, foraging strategies, and habitat utilization by piscivorous waterbirds; and (6) test the feasibility of various alternative methods for managing avian predation on juvenile salmonids and develop recommendations to reduce avian predation, if warranted by the results

Avian Predation on Juvenile Salmonids in the Lower Columbia River: 1998 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Collis, Ken; Adamany, Stephanie; Roby, Daniel D.; Craig, David P.; Lyons, Donald E.

2000-04-01

The authors initiated a field study in 1997 to assess the impacts of fish-eating colonial waterbirds (i.e., terns, cormorants, and gulls) on the survival of juvenile salmonids in the lower Columbia River. Here the authors present results from the 1998 breeding season, the second field season of work on this project. The research objectives in 1998 were to: (1) determine the location, size, nesting chronology, nesting success, and population trajectories of breeding colonies of fish-eating birds in the lower Columbia River; (2) determine diet composition of fish-eating birds, including taxonomic composition and energy content of various prey types; (3) estimate forage fish consumption rates, with special emphasis on juvenile salmonids, by breeding adults and their young; (4) determine the relative vulnerability of different groups of juvenile salmonids to bird predation; (5) identify foraging range, foraging strategies, and habitat utilization by piscivorous waterbirds; and (6) test the feasibility of various alternative methods for managing avian predation on juvenile salmonids and develop recommendations to reduce avian predation, if warranted by the results.

DIVERSITY AND SPATIO-TEMPORAL DISTRIBUTION OF THE ICHTHYOPLANKTON IN THE LOWER AMAZON RIVER, BRAZIL

Directory of Open Access Journals (Sweden)

Diego Maia Zacardi

2017-06-01

Full Text Available The present study investigated (i the taxonomic composition of the larval fish fauna of the lower Amazon River, (ii the structure of the larval assemblage, and (iii the relationship between the abundance of the ichthyoplankton and environmental variables, in order to evaluate the importance of this river sector as spawning and nursery grounds for the region’s fish species. Data were collected monthly between January and December 2013 during the day and at night sampling cycles. A total of 2,295 fish eggs and 46,298 larvae were collected, quantified and classified larvae in 63 taxa. These larvae belonged to species with a variety of reproductive strategies. Individuals at a very early stage of development made up 92% of the specimens collected. High densities of larvae were recorded between January and March, corresponding to the breeding season of most of the species exploited by local fisheries. This peak in density was associated with the period in which rainfall, river water levels, and dissolved oxygen concentrations all peaked, while pH and electrical conductivity reached their lowest levels. The results of the present study confirmed that a number of different fish species use the margins of the lower Amazon river as spawning grounds and nurseries, as well as dispersal routes. This emphasizes the importance of these areas for the reproduction of local fish species and the maintenance of their populations, and highlights the need for the preservation of these areas and the more effective regulation of the closed season. Keywords: Amazon; distribution; fish eggs and larvae; environmental variables; conservation.

Studeren met Hans Rosenberg

NARCIS (Netherlands)

Rutten, R.J.

2001-01-01

Hoe was het om in de jaren zestig te studeren? Laat ik een terugblik ophangen aan een studiemakker, Hans Rosenberg. We vormden samen de sterrekundejaar- gang 1961. Hans studeerde af in 1966 met hoofdvak wiskunde, promoveerde op radiostralingsprocessen in de zonnecorona in 1973, verliet de

Evaluate Potenial Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 2002 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Everett, Scott R.; Tuell, Michael A.; Hesse, Jay A. (Nez Perce Tribe, Department of Fisheries Management, Lapwai, ID)

2004-02-01

The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This report presents a summary of results from the 1997-2002 Phase II data collection and represents the end of phase II. From 1997 to 2001 white sturgeon were captured, marked, and population data were collected in the Snake and Salmon. A total of 1,785 white sturgeon were captured and tagged in the Snake River and 77 in the Salmon River. Since 1997, 25.8 percent of the tagged white sturgeon have been recaptured. Relative density of white sturgeon was highest in the free-flowing segment of the Snake River, with reduced densities of fish in Lower Granite Reservoir, and low densities the Salmon River. Differences were detected in the length frequency distributions of white sturgeon in Lower Granite Reservoir, the free-flowing Snake River and the Salmon River (Chi-Square test, P<0.05). The proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River has shown an increase of 30 percent since the 1970's. Using the Jolly-Seber model, the abundance of white sturgeon <60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 2,483 fish, with a 95% confidence interval of 1,208-7,477. Total annual mortality rate was estimated to be 0.14 (95% confidence interval of 0.12 to 0.17). A total of 35 white sturgeon were fitted with radio-tags during 1999-2002. The movement of these fish ranged from 53 km (33 miles) downstream to 77 km (48 miles) upstream; however, 38.8 percent of the detected movement was less than 0.8 km (0.5 mile). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No

Variation of precipitation for the last 300 years over the middle and lower reaches of the Yellow River

Institute of Scientific and Technical Information of China (English)

ZHENG; Jingyun; HAO; Zhixin; GE; Quansheng

2005-01-01

The precipitation at 17 stations over the middle and lower reaches of the Yellow River is reconstructed during the period of 1736―1910, using the snow and rainfall records in the Qing Dynasty, together with the instrumental observation data of precipitation and farmland soil moisture content. The soil physics model related to rainfall infiltration and the surface water balance equation are taken as main reconstruction methodology. The field infiltration experiment by artificial rainfall is conducted to check the reliability. And the precipitation series over the middle and lower reaches of the Yellow River and its 4 sub-regions are established, going back to 1736. Analysis of the time series indicates that the abrupt change of precipitation from high to low occurs around 1915 over the middle and lower reaches of the Yellow River. During the three periods of 1791―1805, 1816―1830 and 1886―1895, the precipitation is markedly higher than the mean of the series. While both the periods of 1916―1945 and 1981―2000 are characterized by less precipitation. Three periodicities of 22―25a, 3.9a and 2.7a are shown in the precipitation fluctuation over the middle and lower reaches of the Yellow River. Moreover, the periodical signal of 22―25a becomes weaker and weaker since the abrupt change of 1915 and disappears in the late 1940s, and then the periodical signal of 35―40a appears instead.

Lower Red River Meadow Restoration Project : Biennial Report 1996-97.

Energy Technology Data Exchange (ETDEWEB)

LRK Communications; Wildlife Habitat Institute; Pocket Water, Inc.

2003-07-01

The Red River has been straightened and the riparian vegetation corridor eliminated in several reaches within the watershed. The river responded by incision resulting in over-steepened banks, increased sedimentation, elevated water temperatures, depressed groundwater levels, reduced floodplain function, and degraded fish habitat. The Lower Red River Meadow Restoration Project is a multi-phase ecosystem enhancement effort that restores natural physical and biological processes and functions to stabilize the stream channel and establish high quality habitats for fish and wildlife. A natural channel restoration philosophy guides the design and on the ground activities, allowing the channel to evolve into a state of dynamic equilibrium. Two years of planning, two years of restoration in Phases I and II, and one year post-restoration monitoring are complete. By excavating new bends and reconnecting historic meanders, Phase I and II channel realignment increased channel length by 3,060 feet, decreased channel gradient by 25 percent, and increased sinuosity from 1.7 to 2.3. Cross-sectional shapes and point bars were modified to maintain deep pool habitat at low flow and to reconnect the meadow floodplain. Improved soil moisture conditions will help sustain the 31,500 native riparian plantings reestablished within these two phases. Overall, short-term restoration performance was successful. Analyses of long-term parameters document either post-restoration baseline conditions or early stages of evolution toward desired conditions. An adaptive management strategy has helped to improve restoration designs, methods, and monitoring. Lessons learned are being transferred to a variety of audiences to advance the knowledge of ecological restoration and wise management of watersheds.

Upriver transport of dissolved substances in an estuary and sub-estuary system of the lower James River, Chesapeake Bay

Science.gov (United States)

Hong, Bo; Shen, Jian; Xu, Hongzhou

2018-01-01

The water exchange between the James River and the Elizabeth River, an estuary and sub-estuary system in the lower Chesapeake Bay, was investigated using a 3D numerical model. The conservative passive tracers were used to represent the dissolved substances (DS) discharged from the Elizabeth River. The approach enabled us to diagnose the underlying physical processes that control the expansion of the DS, which is representative of potential transport of harmful algae blooms, pollutants from the Elizabeth River to the James River without explicitly simulating biological processes. Model simulations with realistic forcings in 2005, together with a series of processoriented numerical experiments, were conducted to explore the correlations of the transport process and external forcing. Model results show that the upriver transport depends highly on the freshwater discharge on a seasonal scale and maximum upriver transport occurs in summer with a mean transport time ranging from 15-30 days. The southerly/easterly wind, low river discharge, and neap tidal condition all act to strengthen the upriver transport. On the other hand, the northerly/westerly wind, river pulse, water level pulse, and spring tidal condition act to inhibit the upriver transport. Tidal flushing plays an important role in transporting the DS during spring tide, which shortens the travel time in the lower James River. The multivariable regression analysis of volume mean subtidal DS concentration in the mesohaline portion of the James River indicates that DS concentration in the upriver area can be explained and well predicted by the physical forcings (r = 0.858, p = 0.00001).

CO2 emissions from a temperate drowned river valley estuary adjacent to an emerging megacity (Sydney Harbour)

Science.gov (United States)

Tanner, E. L.; Mulhearn, P. J.; Eyre, B. D.

2017-06-01

The Sydney Harbour Estuary is a large drowned river valley adjacent to Sydney, a large urban metropolis on track to become a megacity; estimated to reach a population of 10 million by 2100. Monthly underway surveys of surface water pCO2 were undertaken along the main channel and tributaries, from January to December 2013. pCO2 showed substantial spatio-temporal variability in the narrow high residence time upper and mid sections of the estuary, with values reaching a maximum of 5650 μatm in the upper reaches and as low as 173 μatm in the mid estuary section, dominated by respiration and photosynthesis respectively. The large lower estuary displayed less variability in pCO2 with values ranging from 343 to 544 μatm controlled mainly by tidal pumping and temperature. Air-water CO2 emissions reached a maximum of 181 mmol C m-2 d-1 during spring in the eutrophic upper estuary. After a summer high rainfall event nutrient-stimulated biological pumping promoted a large uptake of CO2 transitioning the Sydney Harbour Estuary into a CO2 sink with a maximum uptake of rate of -10.6 mmol C m-2 d-1 in the mid-section of the estuary. Annually the Sydney Harbour Estuary was heterotrophic and a weak source of CO2 with an air-water emission rate of 1.2-5 mmol C m-2 d-1 (0.4-1.8 mol C m-2 y-1) resulting in a total carbon emission of around 930 tonnes per annum. CO2 emissions (weighted m3 s-1 of discharge per km2 of estuary surface area) from Sydney Harbour were an order of magnitude lower than other temperate large tectonic deltas, lagoons and engineered systems of China, India, Taiwan and Europe but were similar to other natural drowned river valley systems in the USA. Discharge per unit area appears to be a good predictor of CO2 emissions from estuaries of a similar climate and geomorphic class.

Butterfly (Papilionoidea and Hesperioidea) assemblages associated with natural, exotic, and restored riparian habitats along the lower Colorado River, USA

Science.gov (United States)

Nelson, S.M.; Andersen, D.C.

1999-01-01

Butterfly assemblages were used to compare revegetated and natural riparian areas along the lower Colorado River. Species richness and correspondence analyses of assemblages showed that revegetated sites had fewer biological elements than more natural sites along the Bill Williams River. Data suggest that revegetated sites do not provide resources needed by some members of the butterfly assemblage, especially those species historically associated with the cottonwood/willow ecosystem. Revegetated sites generally lacked nectar resources, larval host plants, and closed canopies. The riparian system along the regulated river segment that contains these small revegetated sites also appears to have diminished habitat heterogeneity and uncoupled riparian corridors.Revegetated sites were static environments without the successional stages caused by flooding disturbance found in more natural systems. We hypothesize that revegetation coupled with a more natural hydrology is important for restoration of butterfly assemblages along the lower Colorado River. 

Ecology of nonnative Siberian prawn (Palaemon modestus) in the lower Snake River, Washington, USA

Science.gov (United States)

Erhardt, John M.; Tiffan, Kenneth F.

2016-01-01

We assessed the abundance, distribution, and ecology of the nonnative Siberian prawn Palaemon modestus in the lower Snake River, Washington, USA. Analysis of prawn passage abundance at three Snake River dams showed that populations are growing at exponential rates, especially at Little Goose Dam where over 464,000 prawns were collected in 2015. Monthly beam trawling during 2011–2013 provided information on prawn abundance and distribution in Lower Granite and Little Goose Reservoirs. Zero-inflated regression predicted that the probability of prawn presence increased with decreasing water velocity and increasing depth. Negative binomial models predicted higher catch rates of prawns in deeper water and in closer proximity to dams. Temporally, prawn densities decreased slightly in the summer, likely due to the mortality of older individuals, and then increased in autumn and winter with the emergence and recruitment of young of the year. Seasonal length frequencies showed that distinct juvenile and adult size classes exist throughout the year, suggesting prawns live from 1 to 2 years and may be able to reproduce multiple times during their life. Most juvenile prawns become reproductive adults in 1 year, and peak reproduction occurs from late July through October. Mean fecundity (189 eggs) and reproductive output (11.9 %) are similar to that in their native range. The current use of deep habitats by prawns likely makes them unavailable to most predators in the reservoirs. The distribution and role of Siberian prawns in the lower Snake River food web will probably continue to change as the population grows and warrants continued monitoring and investigation.

[Residues and potential ecological risk assessment of metal in sediments from lower reaches and estuary of Pearl River].

Science.gov (United States)

Xie, Wen-Ping; Wang, Shao-Bing; Zhu, Xin-Ping; Chen, Kun-Ci; Pan, De-Bo; Hong, Xiao-You; Yin, Yi

2012-06-01

In order to investigate the heavy metal concentrations and their potential ecological risks in surface sediments of lower reaches and estuary of Pearl River, 21 bottom sediment samples were collected from lower reaches and estuary of Pearl River. Total contents of Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Pb and Hg in these samples were measured by the inductively coupled plasma mass spectrometry (ICP-MS) and the atomic fluorescence spectrometry (AFS) and using the index of geoaccumulation and the potential ecological risk index to evaluate the pollution degree of heavy metals in the sediments. Results indicated that the concentration of total Fe and total Mn were 41658.73 and 1104.73 mg x kg(-1) respectively and toxic trace metals, such as Cr, Co, Ni, Cu, Zn, As, Se, Cd, Sb, Pb and Hg were 86.62, 18.18, 54.10, 80.20, 543.60, 119.55, 4.28, 10.60, 20.26, 104.58 and 0.520 mg x kg(-1). The descending order of pollution degree of various metals is: Cd > As approximately Zn > Hg > Pb approximately Cu approximately Cr, while the single potential ecological risk followed the order: Cd > Hg > As > Cu > Pb > Zn > Cr. The pollution extent and potential ecological risk of Cd were the most serious among all heavy metals. The distribution pattern of Cd individual potential ecological risk indices is exactly the same as that of general potential ecological risk indices for all heavy metals. Clustering analysis indicates that the sampling stations may be classified into five groups which basically reflected the characteristics of the heavy metal contamination and sedimentation environments along the different river reaches in lower reaches and estuary of Pearl Rive. In general, the serious heavy metal pollution and the high potential ecological risk existed in three river reaches: Chengcun-Shawan, Chengcun-Shundegang and Waihai-Hutiaomen. The pollution degree and potential ecological risk are higher in related river reaches of Beijiang than that in other lower reaches and

Evaluation of Bull Trout Movements in the Tucannon and Lower Snake Rivers, 2002-2006 Project Completion Summary.

Energy Technology Data Exchange (ETDEWEB)

Faler, Michael P. [U.S. Fish and Wildlife Service; Mendel, Glen; Fulton, Carl [Washington Department of Fish and Wildlife

2008-11-20

The Columbia River Distinct Population Segment of bull trout (Salvelinus confluentus) was listed as threatened under the Endangered Species Act in 1998. One of the identified major threats to the species is fragmentation resulting from dams on over-wintering habitats of migratory subpopulations. A migratory subgroup in the Tucannon River appeared to utilize the Snake River reservoirs for adult rearing on a seasonal basis. As a result, a radio telemetry study was conducted on this subgroup from 2002-2006, to help meet Reasonable and Prudent Measures, and Conservation Recommendations associated with the lower Snake River dams in the FCRPS Biological Opinion, and to increase understanding of bull trout movements within the Tucannon River drainage. We sampled 1,109 bull trout in the Tucannon River; 124 of these were surgically implanted with radio tags and PIT tagged, and 681 were only PIT tagged. The remaining 304 fish were either recaptures, or released unmarked. Bull trout seasonal movements within the Tucannon River were similar to those described for other migratory bull trout populations. Bull trout migrated upstream in spring and early summer to the spawning areas in upper portions of the Tucannon River watershed. They quickly moved off the spawning areas in the fall, and either held or continued a slower migration downstream through the winter until early the following spring. During late fall and winter, bull trout were distributed in the lower half of the Tucannon River basin, down to and including the mainstem Snake River below Little Goose Dam. We were unable to adequately radio track bull trout in the Snake River and evaluate their movements or interactions with the federal hydroelectric dams for the following reasons: (1) none of our radio-tagged fish were detected attempting to pass a Snake River dam, (2) our radio tags had poor transmission capability at depths greater than 12.2 m, and (3) the sample size of fish that actually entered the Snake River

Treatment of mid- and lower ureteric calculi: extracorporeal shock-wave lithotripsy vs laser ureteroscopy. A comparison of costs, morbidity and effectiveness

NARCIS (Netherlands)

Bierkens, A. F.; Hendrikx, A. J.; de la Rosette, J. J.; Stultiens, G. N.; Beerlage, H. P.; Arends, A. J.; Debruyne, F. M.

1998-01-01

To determine the efficacy and costs of extracorporeal shock-wave lithotripsy (ESWL) compared with ureteroscopy (URS) in the treatment of mid- and lower ureteric calculi. The records of patients treated primarily by ESWL and URS were analysed retrospectively. Treatment with ESWL included 63 patients

Quantifying Activated Floodplains on a Lowland Regulated River: Its Application to Floodplain Restoration in the Sacramento Valley

Directory of Open Access Journals (Sweden)

Philip B. Williams

2009-09-01

Full Text Available We describe a process and methodology for quantifying the extent of a type of historically prevalent, but now relatively rare, ecologically-valuable floodplains in the Sacramento lowland river system: frequently-activated floodplains. We define a specific metric the “Floodplain Activation Flow” (FAF, which is the smallest flood pulse event that initiates substantial beneficial ecological processes when associated with floodplain inundation. The “Activated Floodplain” connected to the river is then determined by comparison of FAF stage with floodplain topography. This provides a simple definition of floodplain that can be used as a planning, goal setting, monitoring, and design tool by resource managers since the FAF event is the smallest flood and corresponding floodplain area with ecological functionality—and is necessarily also inundated in larger flood events, providing additional ecological functions. For the Sacramento River we selected a FAF definition to be the river stage that occurs in two out of three years for at least seven days in the mid-March to mid-May period and "Activated Floodplains" to be those lands inundated at that stage. We analyzed Activated Floodplain area for four representative reaches along the lower Sacramento River and the Yolo Bypass using stream gauge data. Three of the most significant conclusions are described: (1 The area of active functional floodplain is likely to be less than commonly assumed based on extent of riparian vegetation; (2 Levee setbacks may not increase the extent of this type of ecologically-productive floodplain without either hydrologic or topographic changes; (3 Within the Yolo Bypass, controlled releases through the Fremont Weir could maximize the benefits associated with Activated Floodplain without major reservoir re-operation or grading. This approach identifies a significant opportunity to integrate floodplain restoration with flood management by establishing a FAF stage

30-year changes in the nitrogen inputs to the Yangtze River Basin

International Nuclear Information System (INIS)

Wang, Qinxue; Koshikawa, Hiroshi; Liu, Chen; Otsubo, Kuninori

2014-01-01

To understand both spatial and temporal changes in nitrogen inputs to the Yangtze River Basin (YRB), we collected decadal statistical data for 1980, 1990, 2000 and 2010 at the county level and the annual statistical data for the period 1980–2010 at the provincial level of China. Based on these datasets, we estimated the nitrogen inputs, including the atmospheric deposition, synthetic N fertilizer, biological N fixation and recycling reactive N inputs, such as N from human waste and animal excrement, crop residue recycled as manure, and N emission from burning crop residue. The results showed that, geographically, the variation of the total amount of N input during the last 30 years (δN = N 2010  – N 1980 ) has increased about 0–50 kg ha −1 over most of the area of the YRB. Moreover, it has increased dramatically by about 50–300 kg ha −1 in the Sichuan Basin, the Han River Basin, the Poyang and Dongting lake basins, and the Yangtze Delta as well. Temporally, the total amount of N inputs to the whole YRB was approximately 16.4 Tg N in 2010, which was a 2.0-fold increase over 1980. It increased dramatically in the 1990s and then stabilized at a high level in the 2000s. The major N inputs were human and animal wastes as well as synthetic fertilizers, but they varied regionally. Animal waste was the major input to the water source regions, and its contribution percentage gradually decreased from upper to lower reaches. In contrast, the contribution of N fertilizer increased from upper to lower reaches, and became the major input to the middle and lower reaches. The total N inputs changed slightly in the upper reaches, but increased largely in the middle reaches in the last 30 years. However, in the lower reaches, it had increased remarkably before 2000, and then tended to decrease in the last decade. Finally, the atmospheric N deposition over the basin increased continuously in the last 30 years. (paper)

[Oncomelania hupensis snail distribution in working areas of Yangtze River hydrologic agencies located in middle and lower reaches of Yangtze River in 2016].

Science.gov (United States)

Min, Xu; Suo-Xin, Huang; Zheng-Yuan, Zhao; Ben-Jiao, Hu; Jun, Fu; Si-Min, Dai; Li-Hong, Wen

2016-10-13

To understand the Oncomelania hupensis snail distribution in the working areas of Yangtze River hydrologic agencies located in the middle and lower reaches of the Yangtze River in 2016, so as to provide the evidence for assessing the risk of schistosome infection of hydrological workers and establishing the control strategies. The suspicious environments with O. hupensis snails in the above working areas were selected as study areas, and the snail situation was surveyed by the system sampling method combined with the environmental sampling method. The survey data were collected and analyzed statistically. Totally 19 working areas from 17 hydrological agencies were selected as the investigation sites, among which, 10 working areas from 9 agencies were found with O. hupensis snail distribution. The constituent ratio of the areas with snails reached to 38.81% of the investigation areas, the occurrence rate of frames with snails was 3.08%, and the average density of living snails was 0.07 /0.1 m 2 . By comparison, the average density of living snails and occurrence rate of frames with snails in hydrological agencies under the jurisdiction of the Middle Reaches Administrative Bureau were the most serious among three administrative bureaus of the Yangtze River Water Resources Commission. There are various degrees of O. hupensis breeding in the working areas of hydrological agencies located in the middle and lower reaches of the Yangtze River, and the hydrological workers are facing with the risk of schistosome infection.

Reconnaissance of pharmaceuticals and wastewater indicators in streambed sediments of the lower Columbia River basin, Oregon and Washington

Science.gov (United States)

Nilsen, Elena; Furlong, Edward T.; Rosenbauer, Robert

2014-01-01

One by-product of advances in modern chemistry is the accumulation of synthetic chemicals in the natural environment. These compounds include contaminants of emerging concern (CECs), some of which are endocrine disrupting compounds (EDCs) that can have detrimental reproductive effects. The role of sediments in accumulating these types of chemicals and acting as a source of exposure for aquatic organisms is not well understood. Here we present a small-scale reconnaissance of CECs in bed sediments of the lower Columbia River and several tributaries and urban streams. Surficial bed sediment samples were collected from the Columbia River, the Willamette River, the Tualatin River, and several small urban creeks in Oregon. Thirty-nine compounds were detected at concentrations ranging from 1,000 ng [g sediment]-1 dry weight basis. Columbia River mainstem, suggesting a higher risk of exposure to aquatic life in lower order streams. Ten known or suspected EDCs were detected during the study. At least one EDC was detected at 21 of 23 sites sampled; several EDCs were detected in sediment from most sites. This study is the first to document the occurrence of a large suite of CECs in the sediments of the Columbia River basin. A better understanding of the role of sediment in the fate and effects of emerging contaminants is needed.

Evaluation of Juvenile Salmonid Outmigration and Survival in the Lower Umatilla River Basin, Annual Report 2003-2006.

Energy Technology Data Exchange (ETDEWEB)

White, Tara

2007-02-01

This report summarizes activities conducted by the Oregon Department of Fish and Wildlife's Juvenile Outmigration and Survival M&E project in the Umatilla River subbasin between 2004-2006. Information is used to make informed decisions on hatchery effectiveness, natural production success, passage improvement and flow enhancement strategies. Data collected includes annual estimates of smolt abundance, migration timing, and survival, life history characteristics and productivity status and trends for spring and fall Chinook salmon, coho salmon and summer steelhead. Productivity data provided is the key subbasin scale measure of the effectiveness of salmon and steelhead restoration actions in the Umatilla River. Information is also used for regional planning and recovery efforts of Mid-Columbia River (MCR) ESA-listed summer steelhead. Monitoring is conducted via smolt trapping and PIT-tag interrogation at Three Mile Falls Dam. The Umatilla Juvenile Outmigration and Survival Project was established in 1994 to evaluate the success of management actions and fisheries restoration efforts in the Umatilla River Basin. Project objectives for the 2004-2006 period were to: (1) operate the PIT tag detection system at Three Mile Falls Dam (TMFD), (2) enhance provisional PIT-tag interrogation equipment at the east bank adult fish ladder, (3) monitor the migration timing, abundance and survival of naturally-produced juvenile salmonids and trends in natural production, (4) determine migration parameters and survival of hatchery-produced fish representing various rearing, acclimation and release strategies, (5) evaluate the relative survival between transported and non-transported fish, (6) monitor juvenile life history characteristics and evaluate trends over time, (7) investigate the effects of river, canal, fishway operations and environmental conditions on smolt migration and survival, (8) document the temporal distribution and diversity of resident fish species, and (9

Prognostic analysis and comparison of colon cancer in Han and Hui patients.

Science.gov (United States)

Zhang, Mei; Zhao, Qu-Chuan; Liu, Yan-Peng; Yang, Lei; Zhu, Hong-Ming; Chhetri, Jagadish K

2014-05-07

To investigate the relevant prognostic factors and their differences between colorectal cancer (CRC) patients of Chinese Han and Hui ethnicities in the Beijing region. A retrospective analysis of 880 patients diagnosed with CRC at Xuanwu Hospital, Capital Medical University between September 2001 and September 2011 was performed. Among the 880 patients, 398 and 482 were Hui and Han, respectively. Characteristics including sex, age, diet, tumor size, primary tumor site, Dukes' stage and degree of differentiation were analyzed for their influence on prognosis. Data on dietary structures were recorded through a questionnaire survey conducted during the patient's first visit, return visit or follow-up checkups. Among patients with colon cancer, the 5-year survival rate for patients of Hui ethnicity was lower than that for Han patients (P = 0.025). Six risk factors (age of onset, dietary structure, tumor size, Dukes' stage, location of cancer and degree of differentiation) in both Han and Hui patients were identified as prognostic factors (P dietary structure was a statistically significant factor, and diet varied significantly between the two ethnic groups. Dietary structure has a significant influence on colon cancer prognosis among Han and Hui patients with colon cancer in Beijing, which may cause a difference in their survival rates.

76 FR 61261 - Safety Zone; IJSBA World Finals; Lower Colorado River, Lake Havasu, AZ

Science.gov (United States)

2011-10-04

... navigable waters of Lake Havasu on the lower Colorado River in support of the International Jet Sports... The International Jet Sports Boating Association is sponsoring the IJSBA World Finals. The event will... National Technology Transfer and Advancement Act (NTTAA) (15 U.S.C. 272 note) directs agencies to use...

Lower Colorado River Geographic Response Plan Web Mapping Service, Region 9, 2012, US EPA Region 9

Data.gov (United States)

U.S. Environmental Protection Agency — This map service is comprised of data related to Geographic Response Plans (GRPs) for the Lower Colorado River. Data layers were obtained from nationwide GIS...

Virioplankton Assemblage Structure in the Lower River and Ocean Continuum of the Amazon

Energy Technology Data Exchange (ETDEWEB)

Silva, Bruno S. de O.; Coutinho, Felipe H.; Gregoracci, Gustavo B.; Leomil, Luciana; de Oliveira, Louisi S.; Fróes, Adriana; Tschoeke, Diogo; Soares, Ana Carolina; Cabral, Anderson S.; Ward, Nicholas D.; Richey, Jeffrey E.; Krusche, Alex V.; Yager, Patricia L.; de Rezende, Carlos Eduardo; Thompson, Cristiane C.; Thompson, Fabiano L.; Imperiale, Michael J.

2017-10-04

The Amazon River watershed and its associated plume comprise a vast continental and oceanic area. The microbial activities along this continuum contribute substantially to global carbon and nutrient cycling, and yet there is a dearth of information on the diversity, abundance, and possible roles of viruses in this globally important river. The aim of this study was to elucidate the diversity and structure of virus assemblages of the Amazon River-ocean continuum. Environmental viral DNA sequences were obtained for 12 locations along the river’s lower reach (n= 5) and plume (n= 7). Sequence assembly yielded 29,358 scaffolds, encoding 82,546 viral proteins, with 15 new complete viral genomes. Despite the spatial connectivity mediated by the river, virome analyses and physical-chemical water parameters clearly distinguished river and plume ecosystems. Bacteriophages were ubiquitous in the continuum and were more abundant in the transition region. Eukaryotic viruses occurred mostly in the river, while the plume had more viruses of autotrophic organisms (Prochlorococcus,Synechococcus) and heterotrophic bacteria (Pelagibacter). The viral familiesMicroviridaeandMyoviridaewere the most abundant and occurred throughout the continuum. The major functions of the genes in the continuum involved viral structures and life cycles, and viruses from plume locations and Tapajós River showed the highest levels of functional diversity. The distribution patterns of the viral assemblages were defined not only by the occurrence of possible hosts but also by water physical and chemical parameters, especially salinity. The findings presented here help to improve understanding of the possible roles of viruses in the organic matter cycle along the river-ocean continuum.

IMPORTANCEThe Amazon River forms a vast plume in the

Spatial and temporal trends in PCBs in sediment along the lower Rhône River, France

International Nuclear Information System (INIS)

Desmet, Marc; Mourier, Brice; Mahler, Barbara J.; Van Metre, Peter C.; Roux, Gwenaëlle; Persat, Henri; Lefèvre, Irène; Peretti, Annie

2012-01-01

Despite increasingly strict control of polychlorinated biphenyl (PCB) releases in France since the mid-1970s, PCB contamination of fish recently has emerged as a major concern in the lower Rhône River basin. We measured PCB concentrations in Rhône sediment to evaluate the effects of PCB releases from major urban and industrial areas, sediment redistribution by large floods, and regulatory controls on PCB trends from 1970 to present. Profiles of PCBs (the sum of seven indicator PCB congeners) were reconstructed from sediment cores collected from an off-river rural reference site and from three depositional areas along the Rhône upstream and downstream from the city of Lyon, France. Core chronology was determined from radionuclide profiles and flood deposits. PCB concentrations increased progressively in the downstream direction, and reached a maximum concentration in 1991 of 281 μg/kg at the most downstream site. At the rural reference site and at the upstream Rhône site, PCB concentrations peaked in the 1970s (maximum concentration of 13 and 78 μg/kg, respectively) and have decreased exponentially since then. PCB concentrations in the middle and downstream cores were elevated into the early 1990s, decreased very rapidly until 2000, and since then have remained relatively stable. Congener profiles for three time windows (1965–80, 1986–93, and 2000–08) were similar in the three sediment cores from the Rhône and different from those at the rural reference site. The results indicate that permitted discharges from a hazardous-waste treatment facility upstream from Lyon might have contributed to high concentrations into the 1980-90s, but that industrial discharges from the greater Lyon area and tributaries to the Rhône near Lyon have had a greater contribution since the 1990s. There is little indication that PCB concentration in sediments downstream from Lyon will decrease over at least the short term. -- Highlights: ►We reconstructed trends in PCBs in

Arctic Cisco, Coregonus autumnalis, distribution, migration and spawning in the Mackenzie River

International Nuclear Information System (INIS)

Dillinger, R.E. Jr.; Birt, T.P.; Green, J.M.

1992-01-01

Oil exploration along the Beaufort Sea coast of North America has raised interest in populations of Arctic Cisco. A synopsis is presented of research on Arctic Cisco distributions and spawning activities in the Mackenzie River system. The distribution, migration, and spawning activities of Arctic Cisco in the tributaries of the Mackenzie River system were found to be more extensive than previously reported. The Peel River population had the earliest migration time, mid-July; however, a small movement of mature males upriver also occurred there in mid-September. Major movements of mature males and females took place in both late July and early to mid-Spetember in the Arctic Red River. Migrations in the other river systems occurred in late August and early September. Arctic Ciscoes in the only river south of Great Bear Lake that has been found to contain this species, the Liard River, may show a mixed life history strategy. The apparently long distance the fish must swim, the lack of any known populations in any of the rivers between the Liard and the Great Bear rivers, and the lack of evidence of migrations past Fort Simpson suggest that this population may contain non-anadromous forms. No actual spawning was seen in any of the populations, but possible areas were noted, one in the Peel River and one in the Liard River. 18 refs., 3 figs., 2 tabs

Tidal-Fluvial and Estuarine Processes in the Lower Columbia River: II. Water Level Models, Floodplain Wetland Inundation, and System Zones

Energy Technology Data Exchange (ETDEWEB)

Jay, David A.; Borde, Amy B.; Diefenderfer, Heida L.

2016-04-26

Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland hydrologic regimes at different locations on the river floodplain. A new predictive tool is introduced and validated, the potential SEV (pSEV), which can reduce the need for extensive new data collection in wetland restoration planning. Models of water levels and inundation frequency distinguish four zones encompassing eight reaches. The system zones are the wave- and current-dominated Entrance to river kilometer (rkm) 5; the Estuary (rkm-5 to 87), comprised of a lower reach with salinity, the energy minimum (where the turbidity maximum normally occurs), and an upper estuary reach without salinity; the Tidal River (rkm-87 to 229), with lower, middle, and upper reaches in which river flow becomes increasingly dominant over tides in determining water levels; and the steep and weakly tidal Cascade (rkm-229 to 234) immediately downstream from Bonneville Dam. The same zonation is seen in the water levels of floodplain stations, with considerable modification of tidal properties. The system zones and reaches defined here reflect geological features and their boundaries are congruent with five wetland vegetation zones

Transforming han: a correlational method for psychology and religion.

Science.gov (United States)

Oh, Whachul

2015-06-01

Han is a destructive feeling in Korea. Although Korea accomplished significant exterior growth, Korean society is still experiencing the dark aspects of transforming han as evidenced by having the highest suicide rate in Asia. Some reasons for this may be the fragmentation between North and South Korea. If we can transform han then it can become constructive. I was challenged to think of possibilities for transforming han internally; this brings me to the correlational method through psychological and religious interpretation. This study is to challenge and encourage many han-ridden people in Korean society. Through the psychological and religious understanding of han, people suffering can positively transform their han. They can relate to han more subjectively, and this means the han-ridden psyche has an innate sacredness of potential to transform.

Genetic Diversity of Daphnia pulex in the Middle and Lower Reaches of the Yangtze River

Science.gov (United States)

Wang, Wenping; Zhang, Kun; Deng, Daogui; Zhang, Ya-Nan; Peng, Shuixiu; Xu, Xiaoxue

2016-01-01

Increased human activities and environmental changes may lead to genetic diversity variations of Cladocerans in water. Daphnia pulex are distributed throughout the world and often regarded as a model organism. The 16S rDNA, cytochrome c oxidase subunit I (COI), and 18S genes were used as molecular marks. The genetic diversity and phylogeny of D. pulex obtained from 10 water bodies in the middle and lower reaches of the Yangtze River were studied. For 16S rDNA, COI gene, and 18S gene, the A+T content (65.4%, 58.4%, and 54.6%) was significantly higher than the G+C content (34.6%, 41.6% and 45.4%). This result was consistent with higher A and T contents among invertebrates. Based on the genetic distances of 16S rDNA and COI genes, the genetic differences of D. pulex from 10 water bodies located in the middle and lower reaches of the Yangtze River in China was minimal (0%–0.8% for 16S rDNA and 0%–1.5% for COI gene). However, D. pulex evolved into two branches in the phylogenetic trees, which coincided with its geographical distribution. Compared with D. pulex from other countries, the average genetic distance of D. pulex obtained from 10 water bodies in the middle and lower reaches of the Yangtze River reached 9.1%–10.5%, thereby indicating that D. pulex may have evolved into different subspecies. PMID:27015539

Genetic Diversity of Daphnia pulex in the Middle and Lower Reaches of the Yangtze River.

Directory of Open Access Journals (Sweden)

Wenping Wang

Full Text Available Increased human activities and environmental changes may lead to genetic diversity variations of Cladocerans in water. Daphnia pulex are distributed throughout the world and often regarded as a model organism. The 16S rDNA, cytochrome c oxidase subunit I (COI, and 18S genes were used as molecular marks. The genetic diversity and phylogeny of D. pulex obtained from 10 water bodies in the middle and lower reaches of the Yangtze River were studied. For 16S rDNA, COI gene, and 18S gene, the A+T content (65.4%, 58.4%, and 54.6% was significantly higher than the G+C content (34.6%, 41.6% and 45.4%. This result was consistent with higher A and T contents among invertebrates. Based on the genetic distances of 16S rDNA and COI genes, the genetic differences of D. pulex from 10 water bodies located in the middle and lower reaches of the Yangtze River in China was minimal (0%-0.8% for 16S rDNA and 0%-1.5% for COI gene. However, D. pulex evolved into two branches in the phylogenetic trees, which coincided with its geographical distribution. Compared with D. pulex from other countries, the average genetic distance of D. pulex obtained from 10 water bodies in the middle and lower reaches of the Yangtze River reached 9.1%-10.5%, thereby indicating that D. pulex may have evolved into different subspecies.

Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta, Lower Columbia River, 2007 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Sobocinski, Kathryn; Johnson, Gary; Sather, Nichole [Pacific Northwest National Laboratory

2008-03-17

This document is the first annual report for the study titled 'Ecology of Juvenile Salmonids in Shallow Tidal Freshwater Habitats in the Vicinity of the Sandy River Delta in the Lower Columbia River'. Hereafter, we refer to this research as the Tidal Freshwater Monitoring (TFM) Study. The study is part of the research, monitoring, and evaluation effort developed by the Action Agencies (Bonneville Power Administration, U.S. Army Corps of Engineers, U.S. Bureau of Reclamation) in response to obligations arising from the Endangered Species Act as a result of operation of the Federal Columbia River Power System (FCRPS). The project is performed under the auspices of the Northwest Power and Conservation Council's Columbia Basin Fish and Wildlife Program. The goal of the 2007-2009 Tidal Freshwater Monitoring Study is to answer the following questions: In what types of habitats within the tidal freshwater area of the lower Columbia River and estuary (LCRE; Figure 1) are yearling and subyearling salmonids found, when are they present, and under what environmental conditions?1 And, what is the ecological importance2 of shallow (0-5 m) tidal freshwater habitats to the recovery of Upper Columbia River spring Chinook salmon and steelhead and Snake River fall Chinook salmon? Research in 2007 focused mainly on the first question, with fish stock identification data providing some indication of Chinook salmon presence at the variety of habitat types sampled. The objectives and sub-objectives for the 2007 study were as follows: (1) Habitat and Fish Community Characteristics-Provide basic data on habitat and fish community characteristics for yearling and subyearling salmonids at selected sites in the tidal freshwater reach in the vicinity of the Sandy River delta. (1a) Characterize vegetation assemblage percent cover, conventional water quality, substrate composition, and beach slope at each of six sampling sites in various tidal freshwater habitat types. (1b

Response of dissolved trace metals to land use/land cover and their source apportionment using a receptor model in a subtropic river, China.

Science.gov (United States)

Li, Siyue; Zhang, Quanfa

2011-06-15

Water samples were collected for determination of dissolved trace metals in 56 sampling sites throughout the upper Han River, China. Multivariate statistical analyses including correlation analysis, stepwise multiple linear regression models, and principal component and factor analysis (PCA/FA) were employed to examine the land use influences on trace metals, and a receptor model of factor analysis-multiple linear regression (FA-MLR) was used for source identification/apportionment of anthropogenic heavy metals in the surface water of the River. Our results revealed that land use was an important factor in water metals in the snow melt flow period and land use in the riparian zone was not a better predictor of metals than land use away from the river. Urbanization in a watershed and vegetation along river networks could better explain metals, and agriculture, regardless of its relative location, however slightly explained metal variables in the upper Han River. FA-MLR analysis identified five source types of metals, and mining, fossil fuel combustion, and vehicle exhaust were the dominant pollutions in the surface waters. The results demonstrated great impacts of human activities on metal concentrations in the subtropical river of China. Copyright © 2011 Elsevier B.V. All rights reserved.

Behavior and movement of adult summer steelhead following collection and release, lower Cowlitz River, Washington, 2012--2013

Science.gov (United States)

Kock, Tobias J.; Liedtke, Theresa L.; Ekstrom, Brian K.; Rondorf, Dennis W.; Gleizes, Chris; Dammers, Wolf; Gibson, Scott; Murphy, Jamie

2013-01-01

Executive SummaryHistorically, adult summer steelhead Oncorhynchus mykiss returning to hatcheries on the lower Cowlitz River were sometimes transported and released in the river (recycled) to provide additional angling opportunity for the popular sport fishery in the basin. However, this practice has not been used in recent years because of concerns associated with interactions between hatchery fish and wild fish. Fishery managers were interested in resuming recycling but lacked information regarding effects of this practice on wild steelhead so we conducted a study during 2012–2013 to: (1) enumerate recycled steelhead that returned to the hatchery or were removed by anglers; and (2) determine if steelhead that were not removed from the river remained in the system where they could interact with wild fish.During June–August 2012, a total of 549 summer steelhead were captured at the Cowlitz Salmon Hatchery, tagged, and released downstream near the Interstate 5 Bridge. All recycled steelhead were tagged with a white Floy® tag and opercle-punched; 109 (20 percent) of these fish also were radio-tagged. All adult steelhead that return to the hatchery were handled by hatchery staff so recycled steelhead that returned to the hatchery were enumerated daily. A creel survey and voluntary angler reports were used to determine the number of recycled steelhead that were caught by anglers. We established three fixed telemetry monitoring sites on the mainstem Cowlitz River and eight additional sites were deployed on tributaries to the lower Cowlitz River where wild winter steelhead are known to spawn. We also conducted mobile tracking from a boat during October 2012, November 2012, and January 2013 to locate radio-tagged fish.A total of 10,722 summer steelhead were captured at the Cowlitz Salmon Hatchery in 2012, which was the largest return since 2008. River flows during much of the study period were similar to 2008–2011 average flows, however, high-flow periods in July

Radio telemetry data - Characterizing migration and survival for juvenile Snake River sockeye salmon between the upper Salmon River basin and Lower Granite Dam

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This project estimates survival and characterizes the migration of juvenile sockeye salmon between the upper Salmon River basin in central Idaho and Lower Granite...

An Investigation into Heavy Metal Contamination and Mobilization in the Lower Rouge River, Michigan

Science.gov (United States)

Shihadeh, M.; Forrester, J.; Napieralski, J. A.

2010-12-01

Similar to many densely populated watersheds in the Great Lakes Basin, the Rouge River in Michigan drains a heavily urbanized watershed, which, over time, has accumulated a substantial amount of contamination due to decades of manufacturing and refining industries. Statistically significant levels of heavy metals have been found in the bed sediment of the Rouge; however, little is known about the mobilization of these contaminated bed sediments. The goal of this study was to ascertain the extent to which these potentially contaminated sediments are mobilized and transported downstream. Suspended sediment samples were collected at four sites along the lower Rouge River using composite depth integrated sediment samples three times per week, resulting in a total of twenty samples from each site. Turbidity was measured simultaneously using a YSI datalogger at all sampling locations. Sediment was also extracted from floodplain soil pits and silted vegetation, as well as river bed sediment cores along stream channel cross-sections. Heavy metal concentrations (As, Cd, Cr, Cu, Fe, Pb, Hg, Ni, Se, Zn) were analyzed using ICP-MS and compared against both background characteristics for Michigan soils and EPA Hazardous Criteria Limits. As expected, a positive correlation exists between turbidity and heavy metal concentrations. Even in the sampling sites furthest upstream, heavy metal concentrations exceeded background soil characteristics, with a few also exceeding hazardous criteria limits. The heavy metal concentrations found in the Lower Rouge affirm the elevated pollution classification of the river, depict the overall influence of industrialization on stream health, and verify that contaminated sediments are being deposited in aquatic and floodplain environments during variable flow or high discharge events. Results from this study emphasize the need to remediate bed sediments in the Rouge and suggest that there may be significant bioaccumulation potential for organisms

Modelling non-stationary annual maximum flood heights in the lower Limpopo River basin of Mozambique

Directory of Open Access Journals (Sweden)

Daniel Maposa

2016-05-01

Full Text Available In this article we fit a time-dependent generalised extreme value (GEV distribution to annual maximum flood heights at three sites: Chokwe, Sicacate and Combomune in the lower Limpopo River basin of Mozambique. A GEV distribution is fitted to six annual maximum time series models at each site, namely: annual daily maximum (AM1, annual 2-day maximum (AM2, annual 5-day maximum (AM5, annual 7-day maximum (AM7, annual 10-day maximum (AM10 and annual 30-day maximum (AM30. Non-stationary time-dependent GEV models with a linear trend in location and scale parameters are considered in this study. The results show lack of sufficient evidence to indicate a linear trend in the location parameter at all three sites. On the other hand, the findings in this study reveal strong evidence of the existence of a linear trend in the scale parameter at Combomune and Sicacate, whilst the scale parameter had no significant linear trend at Chokwe. Further investigation in this study also reveals that the location parameter at Sicacate can be modelled by a nonlinear quadratic trend; however, the complexity of the overall model is not worthwhile in fit over a time-homogeneous model. This study shows the importance of extending the time-homogeneous GEV model to incorporate climate change factors such as trend in the lower Limpopo River basin, particularly in this era of global warming and a changing climate. Keywords: nonstationary extremes; annual maxima; lower Limpopo River; generalised extreme value

Velocity mapping in the Lower Congo River: a first look at the unique bathymetry and hydrodynamics of Bulu Reach

Science.gov (United States)

Jackson, P. Ryan; Oberg, Kevin A.; Gardiner, Ned; Shelton, John

2009-01-01

The lower Congo River is one of the deepest, most powerful, and most biologically diverse stretches of river on Earth. The river’s 270 m decent from Malebo Pool though the gorges of the Crystal Mountains to the Atlantic Ocean (498 km downstream) is riddled with rapids, cataracts, and deep pools. Much of the lower Congo is a mystery from a hydraulics perspective. However, this stretch of the river is a hotbed for biologists who are documenting evolution in action within the diverse, but isolated, fish populations. Biologists theorize that isolation of fish populations within the lower Congo is due to barriers presented by flow structure and bathymetry. To investigate this theory, scientists from the U.S. Geological Survey and American Museum of Natural History teamed up with an expedition crew from National Geographic in 2008 to map flow velocity and bathymetry within target reaches in the lower Congo River using acoustic Doppler current profilers (ADCPs) and echo sounders. Simultaneous biological and water quality sampling was also completed. This paper presents some preliminary results from this expedition, specifically with regard to the velocity structure andbathymetry. Results show that the flow in the bedrock controlled Bulu reach of the lower Congo is highly energetic. Turbulent and secondary flow structures can span the full depth of flow (up to 165 m), while coherent bank-to-bank cross-channel flow structures are absent. Regions of flow separation near the banks are isolated from one another and from the opposite bank by high shear, high velocity zones with depth-averaged flow velocities that can exceed 4 m/s.

Socio-Hydrology of Channel Flows in Complex River Basins: Rivers, Canals, and Distributaries in Punjab, Pakistan

Science.gov (United States)

Wescoat, James L.; Siddiqi, Afreen; Muhammad, Abubakr

2018-01-01

This paper presents a socio-hydrologic analysis of channel flows in Punjab province of the Indus River basin in Pakistan. The Indus has undergone profound transformations, from large-scale canal irrigation in the mid-nineteenth century to partition and development of the international river basin in the mid-twentieth century, systems modeling in the late-twentieth century, and new technologies for discharge measurement and data analytics in the early twenty-first century. We address these processes through a socio-hydrologic framework that couples historical geographic and analytical methods at three levels of flow in the Punjab. The first level assesses Indus River inflows analysis from its origins in 1922 to the present. The second level shows how river inflows translate into 10-daily canal command deliveries that vary widely in their conformity with canal entitlements. The third level of analysis shows how new flow measurement technologies raise questions about the performance of established methods of water scheduling (warabandi) on local distributaries. We show how near real-time measurement sheds light on the efficiency and transparency of surface water management. These local socio-hydrologic changes have implications in turn for the larger scales of canal and river inflow management in complex river basins.

Seasonal use of shallow water habitat in the Lower Snake River reservoirs by juvenile fall Chinook salmon

Science.gov (United States)

Tiffan, Kenneth F.; Connor, William P.

2012-01-01

The U.S. Army Corps of Engineers (COE) is preparing a long term management plan for sediments that affect the authorized project purposes of the Lower Granite, Little Goose, Lower Monumental, and Ice Harbor reservoirs (hereafter, the lower Snake River reservoirs), and the area from the mouth of the Snake River to Ice Harbor Dam. We conducted a study from spring 2010 through winter 2011 to describe the habitat use by juvenile Chinook salmon within a selected group of shallow water habitat complexes (spoils to create shallow water habitat, (2) provide evidence for shallow water habitat use by natural subyearlings, (3) provide evidence against large-scale use of shallow water habitat by reservoir-type juveniles, (4) suggest that the depth criterion for defining shallow water habitat (i.e., food web, and intra-specific competition would help to better inform the long-term management plan.

Fish populations under stress. The example of the Lower Neckar river; Fischpopulationen unter Stress. Das Beispiel des Unteren Neckars

Energy Technology Data Exchange (ETDEWEB)

Braunbeck, Thomas; Brauns, Annika; Keiter, Steffen [Sektion Aquatische Oekologie und Toxikologie, Univ. Heidelberg (Germany); Hollert, Henner [Inst. fuer Umweltforschung (Biologie V), Lehr- und Forschungsgebiet Oekosystemanalyse, Rheinisch-Westfaelische Technische Hochschule Aachen, Aachen (Germany); Schwartz, Patrick [Basel Univ. (CH). Mensch-Gesellschaft-Umwelt (MGU)

2009-04-15

Background, aim, and scope: Reports about declines or unusual structures of fish populations in native aquatic systems in Central Europe and North America are in sharp contrast to an obvious improvement of general water quality. The Neckar River may serve as an example of a formerly severely contaminated freshwater system in Southern Germany, the ecological situation of which could be substantially improved over the last three decades. Nevertheless, there are still deficits in the composition of the fish fauna, which cannot be explained by conventional chemical-analytical, hydromorphological and limnological methodologies. Therefore, in search of explanations for ecological deficits, ecotoxicological investigations with an increasing focus on sediment contamination have been performed along the Lower Neckar River over a period of 10 years. In addition to sediment tests, fish populations were screened for genotoxic and embryotoxic effects as well as alterations in the structure of central metabolic organs such as the liver. Materials and methods: Roach (Rutilus rutilus) and gudgeon (Gobio gobio) from the Lower Neckar River were studied with respect to histo- and cytological alterations of the liver as well as the induction of genotoxicity in liver, gut, gills and blood cells by means of the comet and micronucleus assays. At the same time, both native sediments and acetonic sediment extracts were tested for toxicity to zebrafish (Danio rerio) embryos and permanent fish cell cultures. Results: Massive disturbances of the liver ultrastructure indicate severe stress in the fish from the Lower Neckar River despite good supply of nutrition. Both cyto- and embryotoxicity tests document a considerable toxic potential of sediments from the Lower Neckar River, and results of both the comet assay and the micronucleus test provide evidence of the presence of genotoxic agents in the sediments and their effects in fish. There has been no decrease of genotoxicity over the last 10

Formation of A-type granites in the Lower Yangtze River Belt: A perspective from apatite geochemistry

Science.gov (United States)

Jiang, Xiao-Yan; Li, He; Ding, Xing; Wu, Kai; Guo, Jia; Liu, Ji-Qiang; Sun, Wei-Dong

2018-04-01

Apatite is ubiquitous in A-type granites, and can be used to elucidate the volatile contents of the silicate melt, which reflect its source characteristics. A-type granites have been recognized as a distinct group of granites. A1- and A2-type subgroups are produced under different extensional settings. However, the details of the mechanisms behind the distinctive geochemical characteristics of A1- and A2-type granites remain obscure. Belts of Cretaceous A1- and A2-type granites occur along the Lower Yangtze River Belt in eastern China. Here we investigated the major and trace element compositions of apatites from contemporary A1- and A2-type granites at different localities along the Lower Yangtze River Belt, in order to decipher their discrepant source processes. Apatites from A1- and A2-type granites show similar major and trace elements, but differ in their F and Cl concentrations. Apatites from A1-type granites in the eastern part of the Lower Yangtze River Belt have much lower F and higher Cl concentrations compared to A2-type granites in the western part. Moreover, from the east to the west, the F concentrations of apatites from A1-type granites increase, while the Cl concentrations decline. In a subducted plate, F is retained by amphibole, chlorite, serpentine and mica minerals through the amphibolite stage, and finally by phengite and lawsonite during the eclogite stage, whereas, Cl is controlled by amphibole, chlorite and serpentine. The high and varied Cl concentrations in A1 subgroup apatites, therefore, may be attributed to the breakdown of amphibole, chlorite and/or serpentine decomposition during partial melting of subducted oceanic crust releasing a large amount of Cl at shallower depth. In contrast, F is transported to deeper depths in the subducted oceanic crust, and released through breakdown of phengite and lawsonite, making an important contribution to the formation of A2-type granites. Apatites from A1- and A2-type granite samples show regular

Simulation of the Lower Walker River Basin hydrologic system, west-central Nevada, using PRMS and MODFLOW models

Science.gov (United States)

Allander, Kip K.; Niswonger, Richard G.; Jeton, Anne E.

2014-01-01

Walker Lake is a terminal lake in west-central Nevada with almost all outflow occurring through evaporation. Diversions from Walker River since the early 1900s have contributed to a substantial reduction in flow entering Walker Lake. As a result, the lake is receding, and salt concentrations have increased to a level in which Oncorhynchus clarkii henshawi (Lahontan Cutthroat trout) are no longer present, and the lake ecosystem is threatened. Consequently, there is a concerted effort to restore the Walker Lake ecosystem and fishery to a level that is more sustainable. However, Walker Lake is interlinked with the lower Walker River and adjacent groundwater system which makes it difficult to understand the full effect of upstream water-management actions on the overall hydrologic system including the lake level, volume, and dissolved-solids concentrations of Walker Lake. To understand the effects of water-management actions on the lower Walker River Basin hydrologic system, a watershed model and groundwater flow model have been developed by the U.S. Geological Survey in cooperation with the Bureau of Reclamation and the National Fish and Wildlife Foundation.

Observations on sediment sources in the Lower Athabasca River basin: implications of natural hydrocarbons inputs from oil sands deposits

International Nuclear Information System (INIS)

Conly, F.M.

1999-01-01

Government, industry and public concern exists over the environmental consequences of the development of the oil sand deposits in the McMurray Formation in the lower Athabasca River basin, Alberta. The impact of this development is unclear and is undergoing investigation. Investigations to date have focussed on the nature of the effluent produced by the extraction industry and its effect on biotic systems, and on the spatial distribution of hydrocarbon contaminants associated with deposited fluvial sediments. Natural hydrocarbon outcrops may be responsible for observed biomarker responses in areas not exposed to industrial effluent. Given this source of hydrocarbons and doubt concerning its environmental impact, it is difficult to ascertain the impact of oil extraction activities within a fluvial system. A study was conducted to determine the nature and extent of natural hydrocarbon releases within the context of the sediment regime of the lower Athabasca River basin. A description is included of observations from the field and a context is set up for assessing sediment-bound hydrocarbon contaminants in the lower Athabasca River basin. Abstract only included

Major, trace and REE geochemistry of recent sediments from lower Catumbela River (Angola)

Science.gov (United States)

Vinha, Manuela; Silva, M. G.; Cabral Pinto, Marina M. S.; Carvalho, Paula Cristina S.

2016-03-01

The mineralogy, texture, major, trace and rare earth elements, from recent sediment samples collected in the lower Catumbela River, were analysed in this study to characterize and discuss the factors controlling its geochemistry and provide data that can be used as tracers of Catumbela River inputs to the Angolan continental shelf. The sediments are mainly sands and silty-sands, but sandy-silt also occurs and the mineralogy is composed of quartz, feldspar, phyllosilicates, magnetite, ilmenite and also carbonates when the river crosses limestones and marls in the downstream sector. The hydraulic sorting originates magnetite-ilmenite and REE-enriched minerals placers. The mineralogy of the sediments is controlled by the source rocks and the degree of chemical weathering is lower than erosion. The texture is mainly controlled by location. There is enrichment in all the analysed trace elements in the fine grained, clay minerals and Fe-oxy-hydroxides rich sediments, compared to the coarse grained and quartz plus feldspar rich ones. The coarse grained sediments (without the placers) are impoverished in ΣREE when compared with UCC and NASC compositions, while the fine grained sediments have ΣREE contents similar to UCC and NASC. The placers have ΣREE contents up to 959.59 mg/kg. The source composition is the dominant factor controlling the REE geochemistry of the analysed sediments as there is no difference in the (La/Yb)N, (La/Sm)N and (Gd/Yb)N ratios in coarse and fine grained sediments. The sorting of magnetite, ilmenite, zircon, throrite, thorianite, rutile and titanite explain the HREE/LREE enriched patterns of the coarse grained sediments.

Petroleum data for the pre-mid-Devonian basal clastics play, southern Mackenzie Valley

Energy Technology Data Exchange (ETDEWEB)

Lemieux, Y. [Natural Resources Canada, Yellowknife, NT (Canada). Geological Survey of Canada; Gal, L.P. [Northwest Territories Geoscience Office, Yellowknife, NT (Canada)

2008-07-01

This document presented petroleum data from the Mackenzie Corridor exploration area in the Northwest Territories. Both quantitative and qualitative geoscience data was compiled as part of a project under the Secure Canadian Energy Supply program of the Geological Survey of Canada. Three separate reservoir facies have been identified within the study area for their attributes relevant to petroleum exploration. This document defined and described the pre-mid-Devonian basal clastics play in the southern Great Slave Plains region where potential Lower Paleozoic source rocks include organic-rich beds of the Mirage Point and Chinchaga Formations, and regionally widespread, Middle to lower Upper Devonian shale. The play is analogous to the oil producing Middle Devonian clastic plays onlapping the Peace River Arch in northwestern Alberta. The seals, migration and trap styles for the reservoirs were discussed. Exploration risks include a thin and discontinuous reservoir with poor porosity; isolation from potential source beds; inadequate reservoir seals; and timing of hydrocarbon migration with respect to trap development. The petroleum play information was based on very few well penetrations. As such, the pre-mid-Devonian basal clastics play is considered to be a conceptual play that has not yet been adequately explored. 40 refs., 3 tabs., 12 figs.

Evaluate Potential Means of Rebuilding Sturgeon Populations in the Snake River between Lower Granite and Hells Canyon Dams, 1999 Annual Report.

Energy Technology Data Exchange (ETDEWEB)

Tuell, Michael A.; Everett, Scott R. (Nez Perce Tribe, Department of Fisheries Resource Management, Lapwai, ID)

2003-03-01

The specific research goal of this project is to identify means to restore and rebuild the Snake River white sturgeon (Acipenser transmontanus) population to support a sustainable annual subsistence harvest equivalent to 5 kg/ha/yr (CBFWA 1997). Based on data collected, a white sturgeon adaptive management plan will be developed. This 1999 annual report covers the third year of sampling of this multi-year study. In 1999 white sturgeon were captured, marked and population data were collected in the Snake and Salmon rivers. A total of 33,943 hours of setline effort and 2,112 hours of hook-and-line effort was employed in 1999. A total of 289 white sturgeon were captured and tagged in the Snake River and 29 in the Salmon River. Since 1997, 11.1 percent of the tagged white sturgeon have been recaptured. In the Snake River, white sturgeon ranged in total length from 27 cm to 261 cm and averaged 110 cm. In the Salmon River, white sturgeon ranged in total length from 98 cm to 244 cm and averaged 183.5 cm. Using the Jolly-Seber model, the abundance of white sturgeon < 60 cm, between Lower Granite Dam and the mouth of the Salmon River, was estimated at 1,823 fish, with a 95% confidence interval of 1,052-4,221. A total of 15 white sturgeon were fitted with radio-tags. The movement of these fish ranged from 6.4 km (4 miles) downstream to 13.7 km (8.5 miles) upstream; however, 83.6 percent of the detected movement was less than 0.8 kilometers (0.5 miles). Both radio-tagged fish and recaptured white sturgeon in Lower Granite Reservoir appear to move more than fish in the free-flowing segment of the Snake River. No seasonal movement pattern was detected, and no movement pattern was detected for different size fish. Differences were detected in the length frequency distributions of white sturgeon in Lower Granite Reservoir and the free-flowing Snake River (Chi-Square test, P < 0.05). The proportion of white sturgeon greater than 92 cm (total length) in the free-flowing Snake River

Remotely Sensed Predictions and In Situ Observations of Lower Congo River Dynamics in Support of Fish Evolutionary Biology

Science.gov (United States)

Gardiner, N.; Bjerklie, D. M.

2011-12-01

Ongoing research into the evolution of fishes in the lower Congo River suggests a close tie between diversity and hydraulic complexity of flow in the channel. For example, fish populations on each side of the rapids at the head of the lower Congo are within 1.5 km of one another, a distance normally allowing for interbreeding in river systems of comparable size, yet these fish populations show about 5% divergence in their mitochondrial DNA signatures. The proximal reason for this divergence is hydraulic complexity: the speed and turbulence of water moving through the thalweg is a barrier to dispersal for these fishes. Further examination of fish diversity suggests additional correlations of evolutionary divergence of fish clades in association with geomorphic and hydraulic features such as deep pools, extensive systems of rapids, alternating sections of fast and slow current, and recurring whirlpools. Due to prohibitive travel costs, limited field time, and the large geographic domain (approximately 400 river km) of the study area, we undertook a nested set of remote sensing analyses to extract habitat features, geomorphic descriptors, and hydraulic parameters including channel forming velocity, depth, channel roughness, slope, and shear stress. Each of these estimated parameters is mapped for each 1 km segment of the river from the rapids described above to below Inga Falls, a massive cataract where several endemic fish species have been identified. To validate remote sensing estimates, we collected depth and velocity data within the river using gps-enabled sonar measurements from a kayak and Doppler profiling from a motor-driven dugout canoe. Observations corroborate remote sensing estimates of geomorphic parameters. Remote sensing-based estimates of channel-forming velocity and depth were less than the observed maximum channel depth but correlated well with channel properties within 1 km reach segments. This correspondence is notable. The empirical models used

Assessment of hydrological regimes for vegetation on riparian wetlands in Han River Basin, Korea

Directory of Open Access Journals (Sweden)

Jaewon Kwak

2017-01-01

Full Text Available Hydrological regimes are regarded as one of the major determinants for wetland ecosystems, for they influence species composition, succession, productivity, and stability of vegetation communities. Since Korea launched the Four Major River Restoration Project in 2007, the water regimes of many of the riparian wetlands have changed, that is potentially affecting vegetation properties. For ecological conservation and management, it is important to connect hydrological characteristics and vegetation properties. The objective of this study is to investigate the influence of hydrological regimes on vegetation community, and develop a methodology that can connect them. Inundated exceedance probability (IEP and its district concept are suggested to gain insights into hydrological regimes on the Binae wetland that is rehabilitated by the Restoration Project in 2012 and belong to the riparian zone. Results of this study indicate that the areas with P = 0.08 or lower IEPs should have the disturbance for vegetation communities, or could be changed to a hydrophilic vegetation in the study area, and it should be considered in the restoration and rehabilitation project to conserve legally protected or endangered vegetation.

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environmental Impact Statement. Appendix F: Hydrology/Hydraulics and Sedimentation. Appendix G: Hydroregulations. Appendix H: Fluvial Geomorphology

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Lower Snake River Juvenile Salmon Migration Feasibility Report/Environment Impact Statement. Appendix N: Cultural Resources. Appendix O: Public Outreach Program. Appendix P: Air Quality

National Research Council Canada - National Science Library

2002-01-01

... (collectively called the Lower Snake River Project) and their effects on four lower Snake River salmon and steelhead stocks listed for protection under the Endangered Species Act (ESA). The U.S...

Hans mening om hendes krop

DEFF Research Database (Denmark)

Scheuer, Jann

2017-01-01

Bidraget handler om søgninger i danske tekstkorpusser efter 'hendes' hhv. 'hans' + nominal inden for en afstand af to ord. Det er ved hjælp af søgninger i big data undersøgt hvad der knyttes til hende og ham, hvad deres ejendom er: hendes lejlighed o.l. og hvilke attributter de tilskrives hans fi...

Trends in Streamflow Characteristics of Selected Sites in the Elkhorn River, Salt Creek, and Lower Platte River Basins, Eastern Nebraska, 1928-2004, and Evaluation of Streamflows in Relation to Instream-Flow Criteria, 1953-2004

Science.gov (United States)

Dietsch, Benjamin J.; Godberson, Julie A.; Steele, Gregory V.

2009-01-01

The Nebraska Department of Natural Resources approved instream-flow appropriations on the Platte River to maintain fish communities, whooping crane roost habitat, and wet meadows used by several wild bird species. In the lower Platte River region, the Nebraska Game and Parks Commission owns an appropriation filed to maintain streamflow for fish communities between the Platte River confluence with the Elkhorn River and the mouth of the Platte River. Because Elkhorn River flow is an integral part of the flow in the reach addressed by this appropriation, the Upper Elkhorn and Lower Elkhorn Natural Resources Districts are involved in overall management of anthropogenic effects on the availability of surface water for instream requirements. The Physical Habitat Simulation System (PHABSIM) and other estimation methodologies were used previously to determine instream requirements for Platte River biota, which led to the filing of five water appropriations applications with the Nebraska Department of Natural Resources in 1993 by the Nebraska Game and Parks Commission. One of these requested instream-flow appropriations of 3,700 cubic feet per second was for the reach from the Elkhorn River to the mouth of the Platte River. Four appropriations were granted with modifications in 1998, by the Nebraska Department of Natural Resources. Daily streamflow data for the periods of record were summarized for 17 streamflow-gaging stations in Nebraska to evaluate streamflow characteristics, including low-flow intervals for consecutive durations of 1, 3, 7, 14, 30, 60, and 183 days. Temporal trends in selected streamflow statistics were not adjusted for variability in precipitation. Results indicated significant positive temporal trends in annual flow for the period of record at eight streamflow-gaging stations - Platte River near Duncan (06774000), Platte River at North Bend (06796000), Elkhorn River at Neligh (06798500), Logan Creek near Uehling (06799500), Maple Creek near Nickerson

Spatial and temporal trends in occurrence of emerging and legacy contaminants in the Lower Columbia River 2008-2010

Science.gov (United States)

Alvarez, David A.; Perkins, Stephanie D.; Nilsen, Elena B.; Morace, Jennifer L.

2014-01-01

The Lower Columbia River in Oregon and Washington, USA, is an important resource for aquatic and terrestrial organisms, agriculture, and commerce. An 86-mile stretch of the river was sampled over a 3 year period in order to determine the spatial and temporal trends in the occurrence and concentration of water-borne organic contaminants. Sampling occurred at 10 sites along this stretch and at 1 site on the Willamette River using the semipermeable membrane device (SPMD) and the polar organic chemical integrative sampler (POCIS) passive samplers. Contaminant profiles followed the predicted trends of lower numbers of detections and associated concentrations in the rural areas to higher numbers and concentrations at the more urbanized sites. Industrial chemicals, plasticizers, and PAHs were present at the highest concentrations. Differences in concentrations between sampling periods were related to the amount of rainfall during the sampling period. In general, water concentrations of wastewater-related contaminants decreased and concentrations of legacy contaminants slightly increased with increasing rainfall amounts.

Spin Transition in the Lower Mantle: Deep Learning and Pattern Recognition of Superplumes from the Mid-mantle and Mid-mantle Slab Stagnation

Science.gov (United States)

Yuen, D. A.; Shahnas, M. H.; De Hoop, M. V.; Pysklywec, R.

2016-12-01

The broad, slow seismic anomalies under Africa and Pacific cannot be explained without ambiguity. There is no well-established theory to explain the fast structures prevalent globally in seismic tomographic images that are commonly accepted to be the remnants of fossil slabs at different depths in the mantle. The spin transition from high spin to low spin in iron in ferropericlase and perovskite, two major constituents of the lower mantle can significantly impact their physical properties. We employ high resolution 2D-axisymmetric and 3D-spherical control volume models to reconcile the influence of the spin transition-induced anomalies in density, thermal expansivity, and bulk modulus in ferropericlase and perovskite on mantle dynamics. The model results reveal that the spin transition effects increase the mixing in the lower regions of mantle. Depending on the changes of bulk modulus associated with the spin transition, these effects may also cause both stagnation of slabs and rising plumes at mid-mantle depths ( 1600 km). The stagnation may be followed by downward or upward penetration of cold or hot mantle material, respectively, through an avalanche process. The size of these mid-mantle plumes reaches 1500 km across with a radial velocity reaching 20 cm/yr near the seismic transition zone and plume heads exceeding 2500 km across. We will employ a deep-learning algorithm to formulate this challenge as a classification problem where modelling/computation aids in the learning stage for detecting the particular patterns.The parameters based on which the convection models are developed are poorly constrained. There are uncertainties in initial conditions, heterogeneities and boundary conditions in the simulations, which are nonlinear. Thus it is difficult to reconstruct the past configuration over long time scales. In order to extract information and better understand the parameters in mantle convection, we employ deep learning algorithm to search for different

The muddy bottom sediments of the old river beds of the lower Vistula

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Mimier Daria

2016-03-01

Full Text Available The main objective of this study was to characterize the muddy bottom sediments of three hydrologically different old river beds of the lower Vistula, located in the vicinity of Toruń: Port Drzewny, Martwa Wisła and Przybysz. Samples were taken at monthly intervals from April to November 2015 from two (Martwa Wisła and Przybysz or three sampling sites (Port Drzewny located in the central parts of the reservoirs. The bottom sediments of these water bodies were characterized by a low water content and organic matter content expressed as a percentage of dry weight, high organic matter content expressed in units of weight, as well as a high sediment oxygen demand. The most distinct reservoir was Martwa Wisła, most likely due to the lack of a connection with the River Vistula.

Titanium in UK rural, agricultural and urban/industrial rivers: Geogenic and anthropogenic colloidal/sub-colloidal sources and the significance of within-river retention

Energy Technology Data Exchange (ETDEWEB)

Neal, Colin; Jarvie, Helen [Centre for Ecology and Hydrology, Wallingford, Crowmarsh Gifford, Wallingford, OXON, OX10 8BB (United Kingdom); Rowland, Philip, E-mail: apr@ceh.ac.uk [Centre for Ecology and Hydrology, Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, LA1 4AP (United Kingdom); Lawler, Alan; Sleep, Darren; Scholefield, Paul [Centre for Ecology and Hydrology, Lancaster, Lancaster Environment Centre, Library Avenue, Bailrigg, Lancaster, LA1 4AP (United Kingdom)

2011-04-15

Operationally defined dissolved Titanium [Ti] (the < 0.45 {mu}m filtered fraction) in rivers draining rural, agricultural, urban and industrial land-use types in the UK averaged 2.1 {mu}g/l with a range in average of 0.55 to 6.48 {mu}g/l. The lowest averages occurred for the upland areas of mid-Wales the highest just downstream of major sewage treatment works (STWs). [Ti] in rainfall and cloud water in mid-Wales averaged 0.2 and 0.7 {mu}g/l, respectively. Average, baseflow and stormflow [Ti] were compared with two markers of sewage effluent and thus human population: soluble reactive phosphorus (SRP) and boron (B). While B reflects chemically conservative mixing, SRP declined downstream of STW inputs due to in-stream physico-chemical and biological uptake. The results are related to colloidal and sub-colloidal Ti inputs from urban/industrial conurbations coupled with diffuse background (geological) sources and within-river removal/retention under low flows as a result of processes of aggregation and sedimentation. The urban/industrial inputs increased background [Ti] by up to eleven fold, but the total anthropogenic Ti input might well have been underestimated owing to within-river retention. A baseline survey using cross-flow ultrafiltration revealed that up to 79% of the [Ti] was colloidal/nanoparticulate (> 1 kDa i.e. > c. 1-2 nm) for the rural areas, but as low as 28% for the urban/industrial rivers. This raises fundamental issues of the pollutant inputs of Ti, with the possibility of significant complexation of Ti in the sewage effluents and subsequent breakdown within the rivers, as well as the physical dispersion of fine colloids down to the macro-molecular scale. Although not directly measured, the particulate Ti can make an important contribution to the net Ti flux. - Research Highlights: {yields} Filtered Ti in agricultural, urban and industrial UK rivers described. {yields} Highest concentrations occur just downstream of STWs. {yields} The urban

Lower Colorado River Geographic Response Plan Restricted Web Mapping Service, Region 9, 2012, US EPA Region 9

Data.gov (United States)

U.S. Environmental Protection Agency — This map service is comprised of data related to Geographic Response Plans (GRPs) for the Lower Colorado River. Data layers were contributed by various stakeholders...

From gravel to sand. Downstream fining of bed sediments in the lower river Rhine

NARCIS (Netherlands)

Frings, R.M.

2007-01-01

A common characteristic of many rivers is the tendency for bed sediments to become finer in downstream direction. This phenomenon, which is generally known as downstream fining, has a strong effect on the morphologic and hydrodynamic behaviour of a river. The fundamental causes of downstream

Differences of prevalence of dyslipidemia and risk factors related to LDL-c in the patients with abnormal fasting glucose between Uygur and Han in Xinjiang.

Science.gov (United States)

Quan, Li; Hu, Lin; Zhang, Li; Jiang, Sheng

2015-01-01

To evaluate the incidence of dyslipidemia among Uygur and Han patients with impaired fasting glucose (IFG). To investigate the influence factors on LDL-c in this population. This cross-sectional study included a total of 4709 participants, consisting of Uygurs patients (n=2053) and Han patients (n=2656) from Xinjiang province, who were screened for diabetes mellitus. A stratified multistage sampling design was used to collect the participants. The influence factors on LDL-c were analyzed by Logistic regression analysis. Among the IFG patients (n=1757), Uighur IFG group had a higher prevalence of dyslipidemia than that of Han IFG group, 99.8% vs. 63.7%, Pdifference in the Han groups. Logistic regression analysis revealed that risk factors associated with LDL-c were age, total cholesterol and 2 h postprandial blood glucose for the Uighur IFG patients. However, gender and total cholesterol were risk factors for Han IFG patients. Uighur IFG patients had higher incidence of dyslipidemia than that of Han IFG patients. For Uyghur IFG patients, closing follow-up of total cholesterol and 2 h postprandial blood glucose were necessary. As to the Han IFG patients, we should pay more attention to male and total cholesterol in order to lower LDL-c levels. So, appropriately preventive and therapeutic measures should be chosen based on the characteristics of abnormal lipid profiles in different nationality.

High Resolution 3-D Finite-Volume Coastal Ocean Modeling in Lower Campbell River and Discovery Passage, British Columbia, Canada

Directory of Open Access Journals (Sweden)

Yuehua Lin

2014-03-01

Full Text Available The 3-D unstructured-grid, Finite-Volume Coastal Ocean Model (FVCOM was used to simulate the flows in Discovery Passage including the adjoining Lower Campbell River, British Columbia, Canada. Challenges in the studies include the strong tidal currents (e.g., up to 7.8 m/s in Seymour Narrows and tailrace discharges, small-scale topographic features and steep bottom slopes, and stratification affected by the Campbell River freshwater discharges. Two applications of high resolution 3-D FVCOM modeling were conducted. One is for the Lower Campbell River extending upstream as far as the John Hart Hydroelectric dam. The horizontal resolution varies from 0.27 m to 32 m in the unstructured triangular mesh to resolve the tailrace flow. The bottom elevation decreases ~14 m within the distance of ~1.4 km along the river. This pioneering FVCOM river modeling demonstrated a very good performance in simulating the river flow structures. The second application is to compute ocean currents immediately above the seabed along the present underwater electrical cable crossing routes across Discovery Passage. Higher resolution was used near the bottom with inter-layer spacing ranging from 0.125 to 0.0005 of total water depth. The model behaves very well in simulating the strong tidal currents in the area at high resolution in both the horizontal and vertical. One year maximum near bottom tidal current along the routes was then analyzed using the model results.

A spatial model of white sturgeon rearing habitat in the lower Columbia River, USA

Science.gov (United States)

Hatten, J.R.; Parsley, M.J.

2009-01-01

Concerns over the potential effects of in-water placement of dredged materials prompted us to develop a GIS-based model that characterizes in a spatially explicit manner white sturgeon Acipenser transmontanus rearing habitat in the lower Columbia River, USA. The spatial model was developed using water depth, riverbed slope and roughness, fish positions collected in 2002, and Mahalanobis distance (D2). We created a habitat suitability map by identifying a Mahalanobis distance under which >50% of white sturgeon locations occurred in 2002 (i.e., high-probability habitat). White sturgeon preferred relatively moderate to high water depths, and low to moderate riverbed slope and roughness values. The eigenvectors indicated that riverbed slope and roughness were slightly more important than water depth, but all three variables were important. We estimated the impacts that fill might have on sturgeon habitat by simulating the addition of fill to the thalweg, in 3-m increments, and recomputing Mahalanobis distances. Channel filling simulations revealed that up to 9 m of fill would have little impact on high-probability habitat, but 12 and 15 m of fill resulted in habitat declines of ???12% and ???45%, respectively. This is the first spatially explicit predictive model of white sturgeon rearing habitat in the lower Columbia River, and the first to quantitatively predict the impacts of dredging operations on sturgeon habitat. Future research should consider whether water velocity improves the accuracy and specificity of the model, and to assess its applicability to other areas in the Columbia River.

Hans Küng: "Projekt Weltethos "

OpenAIRE

Altmanninger, Maria

2002-01-01

Bei dieser Arbeit werde ich mich vor Allem auf zwei Werke beziehen: Küng,Hans:Projekt Weltethos.Piper.München 1990. Küng,Hans;Kuschel,Karl-Josef (Hg.):Weltfrieden durch Religionsfrieden.Die unter Punkt Acht aufgeführte Stellungnahme wurde ausschließlich von mir verfasst.

SURFACE WATER POLLUTION WITH HEAVY METALS IN THE LOWER CATCHMENT OF JIU RIVER BASIN, ACCORDING TO THE WATER FRAMEWORK DIRECTIVE (2000/60/EC

Directory of Open Access Journals (Sweden)

ADINA SANDA ŞERBAN

2011-03-01

Full Text Available Surface water pollution with heavy metals in the lower catchment of Jiu river basin, according to the Water Framework Directive (2000/60/EC. The Water Framework Directive establishes a single transparent, effective and coherent water policy by defining a strategy to combat pollution by requiring specific action programs.Chemical pollution of surface water presents a threat to the aquatic environment with acute and chronic toxicity to aquatic organisms, accumulation in the ecosystem and losses of habitats and biodiversity, as well as a threat to human health (art.1 from Directive 2008/105/EC regarding the environmental quality standards for water policy.The purpose of this study is to evaluate the chemical status for surface water bodies in the lower catchment of Jiu river basin. The assessment was made taking into account the water impact of four heavy metals: cadmium (Cd, nickel (Ni, mercury (Hg and lead (Pb.

History of river regulation of the Noce River (NE Italy) and related bio-morphodynamic responses

Science.gov (United States)

Serlet, Alyssa; Scorpio, Vittoria; Mastronunzio, Marco; Proto, Matteo; Zen, Simone; Zolezzi, Guido; Bertoldi, Walter; Comiti, Francesco; Prà, Elena Dai; Surian, Nicola; Gurnell, Angela

2016-04-01

The Noce River is a hydropower-regulated Alpine stream in Northern-East Italy and a major tributary of the Adige River, the second longest Italian river. The objective of the research is to investigate the response of the lower course of the Noce to two main stages of hydromorphological regulation; channelization/ diversion and, one century later, hydropower regulation. This research uses a historical reconstruction to link the geomorphic response with natural and human-induced factors by identifying morphological and vegetation features from historical maps and airborne photogrammetry and implementing a quantitative analysis of the river response to channelization and flow / sediment supply regulation related to hydropower development. A descriptive overview is presented. The concept of evolutionary trajectory is integrated with predictions from morphodynamic theories for river bars that allow increased insight to investigate the river response to a complex sequence of regulatory events such as development of bars, islands and riparian vegetation. Until the mid-19th century the river had a multi-thread channel pattern. Thereafter (1852) the river was straightened and diverted. Upstream of Mezzolombardo village the river was constrained between embankments of approximately 100 m width while downstream they are of approximately 50 m width. Since channelization some interesting geomorphic changes have appeared in the river e.g. the appearance of alternate bars in the channel. In 1926 there was a breach in the right bank of the downstream part that resulted in a multi-thread river reach which can be viewed as a recovery to the earlier multi-thread pattern. After the 1950's the flow and sediment supply became strongly regulated by hydropower development. The analysis of aerial images reveals that the multi-thread reach became progressively stabilized by vegetation development over the bars, though signs of some dynamics can still be recognizable today, despite the

[Spatiotemporal variation of Populus euphratica's radial increment at lower reaches of Tarim River after ecological water transfer].

Science.gov (United States)

An, Hong-Yan; Xu, Hai-Liang; Ye, Mao; Yu, Pu-Ji; Gong, Jun-Jun

2011-01-01

Taking the Populus euphratica at lower reaches of Tarim River as test object, and by the methods of tree dendrohydrology, this paper studied the spatiotemporal variation of P. euphratic' s branch radial increment after ecological water transfer. There was a significant difference in the mean radial increment before and after ecological water transfer. The radial increment after the eco-water transfer was increased by 125%, compared with that before the water transfer. During the period of ecological water transfer, the radial increment was increased with increasing water transfer quantity, and there was a positive correlation between the annual radial increment and the total water transfer quantity (R2 = 0.394), suggesting that the radial increment of P. euphratica could be taken as the performance indicator of ecological water transfer. After the ecological water transfer, the radial increment changed greatly with the distance to the River, i.e. , decreased significantly along with the increasing distance to the River (P = 0.007). The P. euphratic' s branch radial increment also differed with stream segment (P = 0.017 ), i.e. , the closer to the head-water point (Daxihaizi Reservoir), the greater the branch radial increment. It was considered that the limited effect of the current ecological water transfer could scarcely change the continually deteriorating situation of the lower reaches of Tarim River.

Multi-Scale Action Effectiveness Research in the Lower Columbia River and Estuary, 2011 - FINAL ANNUAL REPORT

Energy Technology Data Exchange (ETDEWEB)

Sather, Nichole K.; Storch, Adam; Johnson, Gary E.; Teel, D. J.; Skalski, J. R.; Bryson, Amanda J.; Kaufmann, Ronald M.; Woodruff, Dana L.; Blaine, Jennifer; Kuligowski, D. R.; Kropp, Roy K.; Dawley, Earl M.

2012-05-31

The study reported here was conducted by researchers at Pacific Northwest National Laboratory (PNNL), the Oregon Department of Fish and Wildlife (ODFW), the University of Washington (UW), and the National Marine Fisheries Service (NMFS) for the U.S. Army Corps of Engineers, Portland District (USACE). This research project was initiated in 2007 by the Bonneville Power Administration to investigate critical uncertainties regarding juvenile salmon ecology in shallow tidal freshwater habitats of the lower Columbia River. However, as part of the Washington Memorandum of Agreement, the project was transferred to the USACE in 2010. In transferring from BPA to the USACE, the focus of the tidal freshwater research project shifted from fundamental ecology toward the effectiveness of restoration in the Lower Columbia River and estuary (LCRE). The research is conducted within the Action Agencies Columbia Estuary Ecosystem Restoration Program (CEERP). Data reported herein spans the time period May 2010 to September 2011.

The East Asian Summer Monsoon at mid-Holocene: results from PMIP3 simulations

Directory of Open Access Journals (Sweden)

W. Zheng

2013-02-01

Full Text Available Ten Coupled General Circulation Models (CGCMs participated in the third phase of Paleoclimate Modelling Intercomparison Project (PMIP3 are assessed for the East Asian Summer Monsoon (EASM in both the pre-Industrial (PI, 0 ka and mid-Holocene (MH, 6 ka simulations. Results show that the PMIP3 model median captures well the large-scale characteristics of the EASM, including the two distinct features of the Meiyu rainbelt and the stepwise meridional displacement of the monsoonal rainbelt. At mid-Holocene, the PMIP3 model median shows significant warming (cooling during boreal summer (winter over Eurasia continent that are dominated by the changes of insolation. However, the PMIP3 models fail to simulate a warmer annual mean and winter surface air temperature (TAS over eastern China as derived from proxy records. The EASM at MH are featured by the changes of large-scale circulation over Eastern China while the changes of precipitation are not significant over its sub-domains of the Southern China and the lower reaches of Yangzi River. The inter-model differences for the monsoon precipitation can be associated with different configurations of the changes in large-scale circulation and the water vapour content, of which the former determines the sign of precipitation changes. The large model spread for the TAS over Tibetan Plateau has a positive relationship with the precipitation in the lower reaches of Yangzi River, yet this relationship does not apply to those PMIP3 models in which the monsoonal precipitation is more sensitive to the changes of large-scale circulation. Except that the PMIP3 model median captured the warming of annual mean TAS over Tibetan Plateau, no significant improvements can be concluded when compared with the PMIP2 models results.

Effects of river ice on bank morphology and riparian vegetation along Peace River, Clayhurst to Fort Vermilion

International Nuclear Information System (INIS)

Uunila, L.S.

1997-01-01

The effects of river ice and related flooding on the bank morphology and riparian vegetation along 655 km of the Peace River from Clayhurst, British Columbia to Fort Vermilion, Alberta were studied. The river has been regulated for hydroelectric power generation since 1968 and has experienced changes in the hydrologic and ice regimes. The rate of channel adjustments under the new hydrologic regime vary longitudinally, and depend greatly on the succession of riparian vegetation. This study was conducted to determine how much of the variation in both channel adjustment and rate of riparian succession is a result of allogenic effects of ice jams. The direct physical effects of ice and the indirect effects of ice jam flooding on the channel margin were investigated. Long term ice jam severity was found to generally peak well downstream of the principal observation point. The morphology of the channel at the severe ice jam locations fit the classical ice jam criteria of confined tight meanders with several mid-channel islands and shoals. Vegetation damage was the most visible impact to the riparian environment along the Peace River. 27 refs., 1 tab., 8 figs

Quantifying the Geomorphic Dynamics of the Extensively Impacted Lower Yuba River

Science.gov (United States)

Wyrick, J. R.; Pasternack, G. B.; Carley, J. K.; Barker, R.; Massa, D.; Bratovich, P.; Reedy, G.; Johnson, T.

2010-12-01

Traditionally it is has been thought that rivers possess the capability of adjusting their attributes to accommodate varying flow and sediment transport regimes so that sediment in- and out-fluxes are balanced and landform conditions are “stable”. In reality, however, geomorphic drivers and boundary conditions are much more independently dynamic than classically envisioned, such that landforms may always be in a state of adjustment that is normal and appropriate. Rather than thinking of landforms as stable, it is more appropriate to think of them, and the ecosystem services with which they are associated, as resilient in response to change. Knowledge of historic, pre-human baseline conditions or regional reference conditions is limited and may not be as applicable in understanding natural geomorphic and ecosystem services as once envisioned. In light of this natural complexity, a geomorphic assessment of conditions after a large dam or other facility is built and operated may not be as simple as documenting geomorphic instability and attributing that to human impacts relative to the presumed stable baseline conditions. Rather than compare anthropogenically-impacted conditions to theoretical baseline or reference conditions, a more effective approach is to deduce the geomorphic processes in a system under different regimes and evaluate the implications for resiliency of ecosystem services. Through a mechanistic understanding of environmental systems, it may be possible to rationally rehabilitate an ecosystem to achieve resiliency in cases where it has been lost or is desirable to instill, even if it was not historically present. This analytic paradigm is being used to assess the history and on-going geomorphic dynamism of the lower Yuba River (LYR) in northern California. Despite a legacy of massive hydraulic mining waste deposition, dredger re-working of the river valley, dam construction, and flow regulation, the river has been described as lacking the

Hans Viertler: professor, cientista, gestor e amigo Hans Viertler: professor, scientist, manager and friend

Directory of Open Access Journals (Sweden)

Jailson B. de Andrade

2010-01-01

Full Text Available Hans Viertler, a visionary, an example of institutional commitment, a great scientist, excellent and dedicated teacher, highly respected as a professional and admired for his leadership, wisdom, generosity, good humor, professional capacity, and balance. A life dedicated to the consolidation of Chemistry in Brazil, the teaching chemistry, the IQ-USP, the Brazilian Chemical Society (SBQ and the CRQ-fourth region. Hans, a friend with a heart bigger than himself!

Rannarootslaste suurmees Hans Pöhl / Olev Liivik

Index Scriptorium Estoniae

Liivik, Olev, 1975-

2011-01-01

Arvustus: Estlandssvenskarnas hövding. En biografi över Hans Pöhl (1876-1930), estlandssvenskarnas främste företrädare och ledare = Hans Pöhl - rannarootslaste eestvõileja : Hans Pöhl (1876-1930), Eesti rootslaste vaimse liidri ja valgustaja elulugu. Stockholm, 2010

Late Quaternary stream piracy and strath terrace formation along the Belle Fourche and lower Cheyenne Rivers, South Dakota and Wyoming

Science.gov (United States)

Stamm, John F.; Hendricks, Robert R.; Sawyer, J. Foster; Mahan, Shannon A.; Zaprowski, Brent J.; Geibel, Nicholas M.; Azzolini, David C.

2013-09-01

Stream piracy substantially affected the geomorphic evolution of the Missouri River watershed and drainages within, including the Little Missouri, Cheyenne, Belle Fourche, Bad, and White Rivers. The ancestral Cheyenne River eroded headward in an annular pattern around the eastern and southern Black Hills and pirated the headwaters of the ancestral Bad and White Rivers after ~ 660 ka. The headwaters of the ancestral Little Missouri River were pirated by the ancestral Belle Fourche River, a tributary to the Cheyenne River that currently drains much of the northern Black Hills. Optically stimulated luminescence (OSL) dating techniques were used to estimate the timing of this piracy event at ~ 22-21 ka. The geomorphic evolution of the Cheyenne and Belle Fourche Rivers is also expressed by regionally recognized strath terraces that include (from oldest to youngest) the Sturgis, Bear Butte, and Farmingdale terraces. Radiocarbon and OSL dates from fluvial deposits on these terraces indicate incision to the level of the Bear Butte terrace by ~ 63 ka, incision to the level of the Farmingdale terrace at ~ 40 ka, and incision to the level of the modern channel after ~ 12-9 ka. Similar dates of terrace incision have been reported for the Laramie and Wind River Ranges. Hypothesized causes of incision are the onset of colder climate during the middle Wisconsinan and the transition to the full-glacial climate of the late-Wisconsinan/Pinedale glaciation. Incision during the Holocene of the lower Cheyenne River is as much as ~ 80 m and is 3 to 4 times the magnitude of incision at ~ 63 ka and ~ 40 ka. The magnitude of incision during the Holocene might be due to a combined effect of three geomorphic processes acting in concert: glacial isostatic rebound in lower reaches (~ 40 m), a change from glacial to interglacial climate, and adjustments to increased watershed area resulting from piracy of the ancestral headwaters of the Little Missouri River.

Columbia River White Sturgeon (Acipenser Transmontanus) Population Genetics and Early Life History Study, January 1, 1986 to December 31, 1986, Final Report.

Energy Technology Data Exchange (ETDEWEB)

Brannon, Ernest L.

1986-12-01

The 1986 Columbia River white sturgeon investigations continued to assess genetic variability of sturgeon populations isolated in various areas of the Columbia River, and to examine environmental factors in the habitat that may affect early life history success. Baseline data have been collected for three character sets. Twenty-eight loci have been analyzed for differences using electrophoresis, snout shapes were assessed for multivariate distinction, and scute counts have been examined as an index of variability. Fish that reside in the mid-Columbia and lower river have been sufficiently characterized by electrophoresis to compare with up-river areas. To date, few electrophoretic differences have been identified. However, Lake Roosevelt sturgeon sample size will be increased to determine if some of the observed differences from lower river fish are significant. Snout shape has been shown to be easily quantifiable using the digitizing technique. Scute count data initially indicate that variability exists within as well as between areas. Patterns of differentiation of one or more of these data sets may be used to formulate stock transplant guidelines essential for proper management or enhancement of this species. The historical habitat available to sturgeon in the Columbia River has changed through the development of hydroelectric projects. Dams have reduced the velocity and turbulence, and increased light penetration in the water column from less silt. These changes have affected the ability of sturgeon to feed and have made them more vulnerable to predation, which appear to have altered the ability of populations isolated in the reservoirs to sustain themselves. Present studies support the theory that both the biological and physical habitat characteristics of the Columbia River are responsible for reduced sturgeon survival, and justify consideration of enhancement initiatives above Bonneville to improve sturgeon reproductive success.

Thermal and Hydraulic Conditions Supporting the Recruitment of Asian Carp in Seiche Affected Rivers of Lake Erie Basin - A Case Study of the Lower Sandusky River in Ohio