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Sample records for abandoned stream channels

  1. Human-induced stream channel abandonment/capture and filling of floodplain channels within the Atchafalaya River Basin, Louisiana

    USGS Publications Warehouse

    Kroes, Daniel E.; Kraemer, Thomas F.

    2013-01-01

    The Atchafalaya River Basin is a distributary system of the Mississippi River containing the largest riparian area in the lower Mississippi River Valley and the largest remaining forested bottomland in North America. Reductions in the area of open water in the Atchafalaya have been occurring over the last 100 years, and many historical waterways are increasingly filled by sediment. This study examines two cases of swamp channels (3/s) that are filling and becoming unnavigable as a result of high sediment loads and slow water velocities. The water velocities in natural bayous are further reduced because of flow capture by channels constructed for access. Bathymetry, flow, suspended sediment, deposited bottom-material, isotopes, and photointerpretation were used to characterize the channel fill. On average, water flowing through these two channels lost 23% of the suspended sediment load in the studied reaches. Along one of the studied reaches, two constructed access channels diverted significant flow out of the primary channel and into the adjacent swamp. Immediately downstream of each of the two access channels, the cross-sectional area of the studied channel was reduced. Isotopic analyses of bottom-material cores indicate that bed filling has been rapid and occurred after detectable levels of Cesium-137 were no longer being deposited. Interpretation of aerial photography indicates that water is bypassing the primary channels in favor of the more hydraulically efficient access channels, resulting in low or no-velocity flow conditions in the primary channel. These swamp channel conditions are typical in the Atchafalaya River Basin where relict large channel dimensions result in flow velocities that are normally too low to carry fine-grained sediment. Constructed channels increase the rate of natural channel avulsion and abandonment as a result of flow capture.

  2. Abandoned Channel Fill Sequences in Tidal Estuaries

    NASA Astrophysics Data System (ADS)

    Gray, A. B.; Pasternack, G. B.; Goni, M. A.; Watson, E. B.

    2014-12-01

    This study proposes a modification of the current model for abandoned channel fill stratigraphy produced in unidirectional flow river reaches to incorporate seasonal tidal deposition. Evidence supporting this concept came from a study of two consecutive channel abandonment sequences in Ropers Slough of the lower Eel River Estuary in northern California. Aerial photographs showed that Ropers Slough was abandoned around 1943, reoccupied after the 1964 flood, and abandoned again in 1974 with fill continuing to the present. Planform geomorphic characteristics derived from these images were used in conjunction with sub-cm resolution stratigraphic analyses to describe the depositional environment processes and their resultant sedimentary deposits. Results showed that both abandonment sequences recorded quasi-annual scale fluvial/tidal deposition couplets. In both cases tidal deposits contained very little sand, and were higher in organic and inorganic carbon content than the sandier fluvial through-flow deposits. However, the two abandonment fills differed significantly in terms of the temporal progression of channel narrowing and fluvial sediment deposition characteristics. The first abandonment sequence led to a more rapid narrowing of Ropers Slough and produced deposits with a positive relationship between grain size/deposit thickness and discharge. The second abandonment resulted in a much slower narrowing of Ropers Slough and generally thinner fluvial deposits with no clear relationship between grain size/deposit thickness and discharge. The δ13C values and organic nitrogen to organic carbon ratios of deposits from the first phase overlapped with Eel River suspended sediment characteristics found for low flows (1-5 times mean discharge), while those of the second phase were consistent suspended sediment from higher flows (7-10 times mean discharge). The abandoned channel fill sequences appeared to differ due to the topographic steering of bed sediment transport and

  3. Channel morphology and flow structure of an abandoned channel under varying stages

    NASA Astrophysics Data System (ADS)

    Costigan, Katie H.; Gerken, Joseph E.

    2016-07-01

    Abandoned channels are those channels left behind as meandering rivers migrate over their floodplains and remain among the most enigmatic features of the riverscape, especially related to their hydraulics and geomorphology. Abandoned channels are being considered and implemented as restoration and rehabilitation strategies for large rivers but we do not yet have a sound understanding of their hydromorphodynamics. The overall objectives of this work were to assess the bed morphology and flow structure of a large, dynamically connected abandoned channel (e.g., the channel is inundated during annual or decadal floods through bank overflow) under varying stages. Here we document the hydromorphodynamics of an abandoned channel during 3.4, 9.2, and 37.9 return interval discharges using an acoustic Doppler current profiler. Flow separation was observed along the channel entrance during the lowest flow surveying campaign but was not seen during the higher flow campaign. Width to depth ratio and channel width at the exit both progressively decreased from the first surveying campaign, despite the final campaign having the highest measured discharge. Large zones of flow stagnation and recirculation were observed, with depth-averaged velocity vectors not aligning in one direction, in the abandoned channel where water from the entrance was meeting water coming up from the exit during moderate discharges. The abandoned channel has been maintained for at least 25 years due to its low diversion angle and it being perched above the Kansas River. Results of this study provide insights of how flow hydraulics and physical characteristics of abandoned channel change under varying stages.

  4. Roughness coefficients for stream channels in Arizona

    USGS Publications Warehouse

    Aldridge, B.N.; Garrett, J.M.

    1973-01-01

           n in which V = mean cross-sectional velocity of flow, in feet per second; R = hydraulic radius at a cross section, which is the cross-sectional area divided by the wetter perimeter, in feet; Se = energy slope; and n = coefficient of roughness. Many research studies have been made to determine "n" values for open-channel flow (Carter and others, 1963). Guidelines for selecting coefficient of roughness for stream channels are given in most of the literature of stream-channel hydraulics, but few of the data relate directly to streams of Arizona, The U.S> Geological Survey, at the request of the Arizona Highway Department, assembled the color photographs and tables of the Manning "n" values in this report to aid highway engineers in the selection of roughness coefficients for Arizona streams. Most of the photographs show channel reaches for which values of "n" have been assigned by experienced Survey personnel; a few photographs are included for reaches where "n" values have been verified. Verified "n" values are computed from a known discharge and measured channel geometry. Selected photographs of stream channels for which "n" values have been verified are included in U.S. Geological Survey Water-Supply Paper 1849 (Barnes, 1967); stereoscopic slides of Barnes' (1967) photographs and additional photographs can be inspected at U.S> Geological Survey offices in: 2555 E. First Street, Tucson; and 5017 Federal Building, 230 N. First Avenue, Phoenix.

  5. Did ice streams carve martian outflow channels?

    USGS Publications Warehouse

    Lucchitta, B.K.; Anderson, D.M.; Shoji, H.

    1981-01-01

    Outflow channels on Mars1 are long sinuous linear depressions that occur mostly in the equatorial area (??30?? lat.). They differ from small valley networks2 by being larger and arising full born from chaotic terrains. Outflow channels resemble terrestrial stream beds, and their origin has generally been attributed to water3-5 in catastrophic floods6,7 or mudflows8. The catastrophic-flood hypothesis is derived primarily from the morphological similarities of martian outflow channels and features created by the catastrophic Spokane flood that formed the Washington scablands. These similarities have been documented extensively3,6,7, but differences of scale remain a major problemmartian channel features are on the average much larger than their proposed terrestrial analogues. We examine here the problem of channel origin from the perspective of erosional characteristics and the resultant landf orms created by former and present-day ice streams and glaciers on Earth. From morphologic comparisons, an ice-stream origin seems equally well suited to explain the occurrences and form of the outflow channels on Mars, and in contrast with the hydraulic hypothesis, ice streams and ice sheets produce terrestrial features of the same scale as those observed on Mars. ?? 1981 Nature Publishing Group.

  6. Abandoned Rice Fields Make Streams Go Dry in Upland Landscapes

    NASA Astrophysics Data System (ADS)

    Jayawickreme, D.

    2015-12-01

    In South Asia, new economic realities are driving many rural rice farmers out of agriculture. With increasing neglect, abandonment, and rising conversions of centuries old rice fields into other uses, ecological and environmental consequences of these transitions are becoming progressively clear. Field observations in Sri Lanka's central highlands suggest that small shifts in rice to non-rice land uses in headwater watersheds can have a domino effect on the productivity and viability of rice fields and other ecological systems downstream by inflicting groundwater recharge reductions, lowering groundwater yields, and causing other hydrological changes. Preliminary analysis shows that although rice itself is a very water intensive crop, the presence of rain-fed upland rice-fields is hugely beneficial to the watersheds they reside. In particular, water benefits of rice appear to be derived from ponded conditions (3-5 inches of standing water) in which rice is grown, and the contribution rice fields makes to enhance water retention and storage capacity of their watersheds during the monsoon season that coincide with the cropping season. In the absence of well managed rice-fields, hilly upland landscapes produce more runoff and retain little rainwater during the wet season. Furthermore, after centuries of intensive use, much of South Asia's rice fields are nutrient poor and minimally productive without fertilizer applications and other interventions. Consequently, when abandoned, soil erosion and other impacts that affect aquatic ecosystems and watershed health also emerge. Despite these multiple concerns however, little research is currently done to better understand the environmental significance of rice cultivations that are a dominant land-use in many South Asian landscapes. The aim of this presentation is to stir interest among the scientific community to engage more broadly in rice, water, and environmental change research in the face of new economic realities in

  7. A Lower Rhine flood chronology based on the sedimentary record of an abandoned channel fill

    NASA Astrophysics Data System (ADS)

    Toonen, W. H. J.; Winkels, T. G.; Prins, M. A.; de Groot, L. V.; Bunnik, F. P. M.; Cohen, K. M.

    2012-04-01

    The Bienener Altrhein is an abandoned channel of the Lower Rhine (Germany). Following a late 16th century abandonment event, the channel was disconnected from the main stream and the oxbow lake gradually filled with 8 meters of flood deposits. This process still continues today. During annual floods, a limited proportion of overbank discharge is routed across the oxbow lake. Large floods produce individual flood layers, which are visually recognized in the sedimentary sequence. Based on the sedimentary characteristics of these event layers, we created a ~450-year flood chronology for the Lower Rhine. Laser-diffraction grain size measurements were used to assess relative flood magnitudes for individual flood event layers. Continuous sampling at a ~2 cm interval provided a high-resolution record, resolving the record at an annual scale. Standard descriptive techniques (e.g., mean grain size, 95th percentile, % sand) and the more advanced 'end member modelling' were applied to zoom in on the coarse particle bins in the grain size distributions, which are indicative of higher flow velocities. The most recent part of the record was equated to modern discharge measurements. This allows to establish relations between deposited grain size characteristics in the abandoned channel and flood magnitudes in the main river. This relation can also be applied on flood event layers from previous centuries, for which only water level measurements and historical descriptions exist. This makes this method relevant to expand data series used in flood frequency analysis from 100 years to more than 400 years. To date event-layers in the rapidly accumulated sequence, we created an age-depth model that uses organic content variations to tune sedimentation rates between the known basal and top ages. No suitable identifiable organic material for radiocarbon dating was found in the cores. Instead, palynological results (introduction of agricultural species) and palaeomagnetic secular

  8. Abandoned coal mine drainage and its remediation: impacts on stream ecosystem structure and function.

    PubMed

    Bott, Thomas L; Jackson, John K; McTammany, Matthew E; Newbold, J Denis; Rier, Steven T; Sweeney, Bernard W; Battle, Juliann M

    2012-12-01

    The effects of abandoned mine drainage (AMD) on streams and responses to remediation efforts were studied using three streams (AMD-impacted, remediated, reference) in both the anthracite and the bituminous coal mining regions of Pennsylvania (USA). Response variables included ecosystem function as well as water chemistry and macroinvertebrate community composition. The bituminous AMD stream was extremely acidic with high dissolved metals concentrations, a prolific mid-summer growth of the filamentous alga, Mougeotia, and > 10-fold more chlorophyll than the reference stream. The anthracite AMD stream had a higher pH, substrata coated with iron hydroxide(s), and negligible chlorophyll. Macroinvertebrate communities in the AMD streams were different from the reference streams, the remediated streams, and each other. Relative to the reference stream, the AMD stream(s) had (1) greater gross primary productivity (GPP) in the bituminous region and undetectable GPP in the anthracite region, (2) greater ecosystem respiration in both regions, (3) greatly reduced ammonium uptake and nitrification in both regions, (4) lower nitrate uptake in the bituminous (but not the anthracite) region, (5) more rapid phosphorus removal from the water column in both regions, (6) activities of phosphorus-acquiring, nitrogen-acquiring, and hydrolytic-carbon-acquiring enzymes that indicated extreme phosphorus limitation in both regions, and (7) slower oak and maple leaf decomposition in the bituminous region and slower oak decomposition in the anthracite region. Remediation brought chlorophyll concentrations and GPP nearer to values for respective reference streams, depressed ecosystem respiration, restored ammonium uptake, and partially restored nitrification in the bituminous (but not the anthracite) region, reduced nitrate uptake to an undetectable level, restored phosphorus uptake to near normal rates, and brought enzyme activities more in line with the reference stream in the bituminous

  9. Abandoned coal mine drainage and its remediation: impacts on stream ecosystem structure and function.

    PubMed

    Bott, Thomas L; Jackson, John K; McTammany, Matthew E; Newbold, J Denis; Rier, Steven T; Sweeney, Bernard W; Battle, Juliann M

    2012-12-01

    The effects of abandoned mine drainage (AMD) on streams and responses to remediation efforts were studied using three streams (AMD-impacted, remediated, reference) in both the anthracite and the bituminous coal mining regions of Pennsylvania (USA). Response variables included ecosystem function as well as water chemistry and macroinvertebrate community composition. The bituminous AMD stream was extremely acidic with high dissolved metals concentrations, a prolific mid-summer growth of the filamentous alga, Mougeotia, and > 10-fold more chlorophyll than the reference stream. The anthracite AMD stream had a higher pH, substrata coated with iron hydroxide(s), and negligible chlorophyll. Macroinvertebrate communities in the AMD streams were different from the reference streams, the remediated streams, and each other. Relative to the reference stream, the AMD stream(s) had (1) greater gross primary productivity (GPP) in the bituminous region and undetectable GPP in the anthracite region, (2) greater ecosystem respiration in both regions, (3) greatly reduced ammonium uptake and nitrification in both regions, (4) lower nitrate uptake in the bituminous (but not the anthracite) region, (5) more rapid phosphorus removal from the water column in both regions, (6) activities of phosphorus-acquiring, nitrogen-acquiring, and hydrolytic-carbon-acquiring enzymes that indicated extreme phosphorus limitation in both regions, and (7) slower oak and maple leaf decomposition in the bituminous region and slower oak decomposition in the anthracite region. Remediation brought chlorophyll concentrations and GPP nearer to values for respective reference streams, depressed ecosystem respiration, restored ammonium uptake, and partially restored nitrification in the bituminous (but not the anthracite) region, reduced nitrate uptake to an undetectable level, restored phosphorus uptake to near normal rates, and brought enzyme activities more in line with the reference stream in the bituminous

  10. Evaluation of Metal Toxicity in Streams Affected by Abandoned Mine Lands, Upper Animas River Watershed, Colorado

    USGS Publications Warehouse

    Besser, John M.; Allert, Ann L.; Hardesty, Douglas K.; Ingersoll, Christopher G.; May, Thomas W.; Wang, Ning; Leib, Kenneth J.

    2001-01-01

    Acid drainage from abandoned mines and from naturally-acidic rocks and soil in the upper Animas River watershed of Colorado generates elevated concentrations of acidity and dissolved metals in stream waters and deposition of metal-contaminated particulates in streambed sediments, resulting in both toxicity and habitat degradation for stream biota. High concentrations of iron (Fe), aluminum (Al), zinc (Zn), copper (Cu), cadmium (Cd), and lead (Pb) occur in acid streams draining headwaters of the upper Animas River watershed, and high concentrations of some metals, especially Zn, persist in circumneutral reaches of the Animas River and Mineral Creek, downstream of mixing zones of acid tributaries. Seasonal variation of metal concentrations is reflected in variation in toxicity of stream water. Loadings of dissolved metals to the upper Animas River and tributaries are greatest during summer, during periods of high stream discharge from snowmelt and monsoonal rains, but adverse effects on stream biota may be greater during winter low-flow periods, when stream flows are dominated by inputs of groundwater and contain greatest concentrations of dissolved metals. Fine stream-bed sediments of the upper Animas River watershed also contain elevated concentrations of potentially toxic metals. Greatest sediment metal concentrations occur in the Animas River upstream from Silverton, where there are extensive deposits of mine and mill tailings, and in mixing zones in the Animas River and lower Mineral Creek, where precipitates of Fe and Al oxides also contain high concentrations of other metals. This report summarizes the findings of a series of toxicity studies in streams of the upper Animas River watershed, conducted on-site and in the laboratory between 1998 and 2000. The objectives of these studies were: (1) to determine the relative toxicity of stream water and fine stream-bed sediments to fish and invertebrates; (2) to determine the seasonal range of toxicity in stream

  11. THERMAL HETEROGENEITY, STREAM CHANNEL MORPHOLOGY, AND SALMONID ABUNDANCE IN NORTHEASTERN OREGON STREAMS

    EPA Science Inventory

    Heterogeneity in stream water temperatures created by local influx of cooler subsurface waters into geomorphically complex stream channels was associated with increased abundance of rainbow trout (Oncorhynchus mykiss) and chinook salmon (O. tshawytscha) in northeastern Oregon. Th...

  12. Measurement of stream channel habitat using sonar

    USGS Publications Warehouse

    Flug, M.; Seitz, H.; Scott, J.

    1998-01-01

    An efficient and low cost technique using a sonar system was evaluated for describing channel geometry and quantifying inundated area in a large river. The boat-mounted portable sonar equipment was used to record water depths and river width measurements for direct storage on a laptop computer. The field data collected from repeated traverses at a cross-section were evaluated to determine the precision of the system and field technique. Results from validation at two different sites showed average sample standard deviations (S.D.s) of 0.12 m for these complete cross-sections, with coefficient of variations of 10%. Validation using only the mid-channel river cross-section data yields an average sample S.D. of 0.05 m, with a coefficient of variation below 5%, at a stable and gauged river site using only measurements of water depths greater than 0.6 m. Accuracy of the sonar system was evaluated by comparison to traditionally surveyed transect data from a regularly gauged site. We observed an average mean squared deviation of 46.0 cm2, considering only that portion of the cross-section inundated by more than 0.6 m of water. Our procedure proved to be a reliable, accurate, safe, quick, and economic method to record river depths, discharges, bed conditions, and substratum composition necessary for stream habitat studies. ?? 1998 John Wiley & Sons, Ltd.

  13. Dynamics of Transmissionlosses In Arid Stream Channels

    NASA Astrophysics Data System (ADS)

    Lange, J.; Mostert, A.; Wessels, C.

    In dry areas streamflow losses of ephemeral rivers are important contributions to groundwater recharge. The importance of these losses increases with aridity U in hy- perarid areas they often form the only freshwater source for aquifers sustaining water supply and life of the local population. However, just in these areas little is known about processes involved, as gauging and monitoring of surface water flow is made difficult due to the low population, remoteness of hydrological stations and short du- rations of floods. Using a physically based flow routing scheme on an event basis this study wants to contribute to the knowledge of the nature and dynamics of chan- nel transmission losses in large arid stream channels. In the 15500 km2 Kuiseb River catchment, western Namibia, annual rainfall decreases from 275 in the east to just about 0 in the west. With a distinct drop in altitude the downstream part of the basin makes up one of the driest regions in the world. A 200 km channel in the lower reaches of the Kuiseb River serves as an ideal field laboratory to simulate the transmission of flash floods because of the following reasons: i) Almost 20 years of flow records up and downstream ii) Negligible lateral inflow along the reach due to hyperarid condi- tions iii) Comparatively frequent flows due to the semiarid headwaters Hydrographs of two upstream stations serve as input for the routing scheme in a 5 min time step. Geometric information required is taken from aerial photography, topographical maps and surveyed cross sections. At the downstream end of the reach 20 simulated hy- drographs are compared with gauged events. Without calibration the routing scheme nicely documents that small floods (< 60-80 m3/s) are not significantly reduced, if they travel on a wet channel, while under the same circumstances large floods (> 120- 140 m3/s) loose up to 50% of their runoff peak. This difference is important for the assessment of groundwater recharge and may be

  14. Stream Channelization: Conflict Between Ditchers, Conservationists

    ERIC Educational Resources Information Center

    Gillette, Robert

    1972-01-01

    Summarizes the argument between the advocates of stream straightening for flood control, drainage, and navigation, and those concerned with the maintenance of ecological communities and the aesthetic values of natural" streams. (AL)

  15. Effects of Stream Channel Characteristics on Nitrate Delivery to Streams and In-Stream Denitrification Rates, Raccoon River, Iowa

    NASA Astrophysics Data System (ADS)

    Prestegaard, K. L.; O'Connell, M.

    2004-05-01

    Streams in agricultural areas often exhibit significant channel and sediment modifications; they are often incised and transport more fine sediment than non-agricultural streams. These channel characteristics can influence stream water quality by modifying surface-groundwater interactions. In the Raccoon River basin, channel incision increases the delivery of nitrate from the groundwater to the streams. The sandy in-stream sediments, however, serve as very effective sites for in-stream denitrification. Nitrate delivery and in-stream denitrification was examined in 3 subwatersheds of the Raccoon River. Stream morphology, water quality, and sediment characteristics were measured at 35 sites with varying land uses. Headwater stream nitrate concentration increased with percent row crops and the amount of channel incision. Downstream sites showed a wide variation in nitrate concentration with land use. Stream nitrate concentrations were measured at 6 sites in each of 3 streams with high percentages of row crop land uses during high summer baseflow following the 1993 floods and during average summer baseflow in 1995. Nitrate concentrations were systematically higher for the high baseflow conditions of 1993 than the average year (1995). This change in nitrate concentration is interpreted as the increased effectiveness of nitrate delivery to the stream during periods of high water tables. The effect was most pronounced in incised reaches. All 3 streams show downstream decreases in nitrate concentration. Water samples for all the sites in the watersheds were analyzed for nitrogen isotopic composition. The nitrogen isotopic composition shifts with towards higher d 15N values with decreasing nitrate concentration. This is consistent with denitrification reactions that selectively remove the 14N leaving a higher proportion of 15N in the nitrate. This suggests that most of the downstream decrease in nitrate concentrations is a result of in-stream denitrification. The high rates

  16. Effects of permafrost on stream channel behavior in Arctic Alaska

    USGS Publications Warehouse

    Scott, Kevin M.

    1978-01-01

    Sites with drainage areas ranging from 88 to 12,200 sq km were monitored on five streams in northern Alaska during the breakup in 1976 to determine (1) the effects of frozen bed and bank material on channel behavior, and (2) the importance of the annual breakup flood in forming the channels of arctic streams. The thawing and concomitant erosion of channels varied with changes in bed-material size, channel pattern, drainage area, and climate. The response of channels to breakup flooding ranged from total permafrost control of channel processes, including both bed scour and lateral erosion, to only brief restriction of channel behavior early in the rise of the flooding. The watershed characteristic that appears to explain much of this variation is size of drainage area. (Woodard-USGS)

  17. CHANNEL EVOLUTION IN MODIFIED ALLUVIAL STREAMS.

    USGS Publications Warehouse

    Simon, Andrew; Hupp, Cliff R.

    1987-01-01

    This study (a) assesses the channel changes and network trends of bed level response after modifications between 1959 and 1972 of alluvial channels in western Tennessee and (b) develops a conceptual model of bank slope development to qualitatively assess bank stability and potential channel widening. A six-step, semiquantitative model of channel evolution in disturbed channels was developed by quantifying bed level trends and recognizing qualitative stages of bank slope development. Development of the bank profile is defined in terms of three dynamic and observable surfaces: (a) vertical face (70 to 90 degrees), (b) upper bank (25 to 50 degrees), and (c) slough line (20 to 25 degrees).

  18. Optimized transmission of JPEG2000 streams over wireless channels.

    PubMed

    Thomos, Nikolaos; Boulgouris, Nikolaos V; Strintzis, Michael G

    2006-01-01

    The transmission of JPEG2000 images over wireless channels is examined using reorganization of the compressed images into error-resilient, product-coded streams. The product-code consists of Turbo-codes and Reed-Solomon codes which are optimized using an iterative process. The generation of the stream to be transmitted is performed directly using compressed JPEG2000 streams. The resulting scheme is tested for the transmission of compressed JPEG2000 images over wireless channels and is shown to outperform other algorithms which were recently proposed for the wireless transmission of images.

  19. Channel Forming Discharges and Scaling Relationships in Small Streams

    NASA Astrophysics Data System (ADS)

    Brayshaw, D. D.

    2008-12-01

    One of the major challenges in predicting or mitigating the impacts of disturbance on hydrologic systems is to link changes in hydrology to changes in sediment delivery and transport. Because of the complexity of modelling, usually only one system is considered in isolation, with any potential changes in the corresponding system inferred. For instance, a study of a small watershed might consider changes to peak flows or to sediment delivery to the channel, but not alteration in channel pattern caused by those changes. Linking our understanding of expected changes in hydrology and sediment transport is therefore important for improving land use management. In order to improve this understanding, the development of models and concepts linking hydrologic change to geomorphic change, and vice versa, is necessary. Channel and reach parameters (such as width, depth, slope, and channel pattern) reflect the adjustment of the stream channel to inputs of water, wood and sediment from upstream and upslope. Therefore, channel parameters can be used as indicators which synthesize the hydrologic and geomorphic processes occurring in a watershed (Goodwin et al, 1998). Two parameters which are particularly relevant are the bankfull discharge and the effective discharge. Bankfull discharge (Wolman and Leopold, 1957) is defined as the discharge at which the stream channel is full to the top of its banks, but not flooding over the bank. Effective discharge (Wolman and Miller, 1960) is defined as the discharge that, averaged over time, transports the most sediment. Estimating the frequency, magnitude, and duration of bankfull and effective discharge in a single stream reach provides an indication of the stream channel's stability and the frequency with which geomorphically effective events occur in the watershed upstream. Determining the bankfull and effective discharge for multiple streams across a region enables regionalization, consideration of scaling relationships, and evaluation

  20. Groundwater discharge along a channelized Coastal Plain stream

    USGS Publications Warehouse

    LaSage, D.M.; Sexton, J.L.; Mukherjee, A.; Fryar, A.E.; Greb, S.F.

    2008-01-01

    In the Coastal Plain of the southeastern USA, streams have commonly been artificially channelized for flood control and agricultural drainage. However, groundwater discharge along such streams has received relatively little attention. Using a combination of stream- and spring-flow measurements, spring temperature measurements, temperature profiling along the stream-bed, and geologic mapping, we delineated zones of diffuse and focused discharge along Little Bayou Creek, a channelized, first-order perennial stream in western Kentucky. Seasonal variability in groundwater discharge mimics hydraulic-head fluctuations in a nearby monitoring well and spring-discharge fluctuations elsewhere in the region, and is likely to reflect seasonal variability in recharge. Diffuse discharge occurs where the stream is incised into the semi-confined regional gravel aquifer, which is comprised of the Mounds Gravel. Focused discharge occurs upstream where the channel appears to have intersected preferential pathways within the confining unit. Seasonal fluctuations in discharge from individual springs are repressed where piping results in bank collapse. Thereby, focused discharge can contribute to the morphological evolution of the stream channel. ?? 2008 Elsevier B.V. All rights reserved.

  1. Groundwater Discharge along a Channelized Coastal Plain Stream

    SciTech Connect

    LaSage, Danita M; Sexton, Joshua L; Mukherjee, Abhijit; Fryar, Alan E; Greb, Stephen F

    2015-10-01

    In the Coastal Plain of the southeastern USA, streams have commonly been artificially channelized for flood control and agricultural drainage. However, groundwater discharge along such streams has received relatively little attention. Using a combination of stream- and spring-flow measurements, spring temperature measurements, temperature profiling along the stream-bed, and geologic mapping, we delineated zones of diffuse and focused discharge along Little Bayou Creek, a channelized, first-order perennial stream in western Kentucky. Seasonal variability in groundwater discharge mimics hydraulic-head fluctuations in a nearby monitoring well and spring-discharge fluctuations elsewhere in the region, and is likely to reflect seasonal variability in recharge. Diffuse discharge occurs where the stream is incised into the semi-confined regional gravel aquifer, which is comprised of the Mounds Gravel. Focused discharge occurs upstream where the channel appears to have intersected preferential pathways within the confining unit. Seasonal fluctuations in discharge from individual springs are repressed where piping results in bank collapse. Thereby, focused discharge can contribute to the morphological evolution of the stream channel.

  2. Riparian vegetation recovery patterns following stream channelization: a geomorphic perspective

    USGS Publications Warehouse

    Hupp, C.R.

    1992-01-01

    Hundreds of kilometres of West Tennessee streams have been channelized since the turn of the century. After a stream is straightened, dredged, or cleared, basin-wide ecologic, hydrologic, and geomorphic processes bring about an integrated, characteristic recovery sequence. The rapid pace of channel responses to channelization provides an opportunity to document and interpret vegetation recovery patterns relative to otherwise long-term, concomitant evolution of river geomorphology. The linkage of channel bed aggradation, woody vegetation establishment, and bank accretion all lead to recovery of the channel. Pioneer species are hardy and fast growing, and can tolerate moderate amounts of slope instability and sediment deposition; these species include river birch (Betula nigra), black willow (Salix nigra), boxelder (Acer negundo), and silver maple (Acer saccharinum). High stem densities and root-mass development appear to enhance bank stability. Tree-ring analyses suggest that on average 65 yr may be required for recovery after channelization. -from Author

  3. Determination of channel change for selected streams, Maricopa County, Arizona

    USGS Publications Warehouse

    Capesius, Joseph P.; Lehman, Ted W.

    2002-01-01

    In Maricopa County, Arizona, 10 sites on seven streams were studied to determine the lateral and vertical change of the channel. Channel change was studied over time scales ranging from individual floods to decades using cross-section surveys, discharge measurements, changes in the point of zero flow, and repeat photography. All of the channels showed some change in cross-section area or hydraulic radius over the time scales studied, but the direction and mag-nitude of change varied considerably from one flow, or series of flows, to another. The documentation of cross-section geometry for streams in Maricopa County for long-term monitoring was begun in this study.

  4. Effects of Concrete Channels on Stream Biogeochemistry, Maryland Coastal Plain

    NASA Astrophysics Data System (ADS)

    Prestegaard, K. L.; Gilbert, L.; Phemister, K.

    2005-05-01

    In the 1950's and 60's, extensive networks of cement-lined channels were built in suburban watersheds near Washington, D.C. to convey storm water to downstream locations. These cement-lined stream channels limit interactions between surface and groundwater and they provide sources of alkalinity in Maryland Coastal Plain watersheds that normally have low alkalinity. This project was designed to 1) compare base flow water chemistry in headwater reaches of urban and non-urban streams, and 2) to evaluate downstream changes in water chemistry in channelized urban streams in comparison with non-urban reference streams. During a drought year, headwater streams in both urban and non-urban sites had significant concentrations of Fe(II) that were discharged from groundwater sources and rapidly oxidized by iron-oxidizing bacteria. During a wet year, the concentrations of Fe(II) were higher in headwater urban streams than in the non-urban streams. This suggests that impervious surfaces in headwater urban watersheds prevent the recharge of oxygen-rich waters during storm events, which maintains iron-rich groundwater discharge to the stream. Downstream changes in water chemistry are prominent in cement-lined urban channels because they are associated with distinctive microbial communities. The headwater zones of channelized streams are dominated by iron-ozidizing bacteria, that are replaced downstream by manganese-oxidizing zones, and replaced further downstream by biofilms dominated by photosynthesizing cyanobacteria. The reaches dominated by cyanobacteria exhibit diurnal changes in pH due to uptake of CO2 for photosynthesis. Diurnal changes range from 7.5 to 8.8 in the summer months to 7.0 to 7.5 in the cooler months, indicating both the impact of photosynthesis and the additional source of alkalinity provided by concrete. The dissolved oxygen, pH, and other characteristics of tributaries dominated by cyanobacteria are similar to the water chemistry characteristics observed in

  5. Arid ephemeral stream classification using channel geometry and basin characteristics

    NASA Astrophysics Data System (ADS)

    Sutfin, N. A.; Wohl, E. E.; Shaw, J.

    2011-12-01

    Because understanding of ephemeral stream characteristics is limited and many stream classifications do not adequately describe them, it is necessary to develop a better understanding of these dryland fluvial systems and develop more precise terminology to discuss their physical attributes. In addition to development of a geomorphic classification system, we examine relationships between basin characteristics and channel geometry that will indicate where these ephemeral stream types might occur. Our conceptual model includes five geomorphic ephemeral stream types; 1) braided washes, 2) incised alluvium, 3) bedrock with alluvium, 4) bedrock, and 5) piedmont headwater channels. Preliminary watershed classification and cluster analysis of the U.S. Sonoran Desert was conducted using NHD 10-digit Hydrologic Unit Boundaries, PRISM precipitation data, state geologic survey lithology, and data derived from 30m DEMs. A total of 85 reaches were surveyed on the U.S. Army Yuma Proving Ground in southwestern Arizona representing the five stream types within three watershed categories. Following delineation of small-scale watershed characteristics using 10m DEMs for each reach location, statistical analysis will be performed to examine correlations and significant relationships among stream type, basin and channel characteristics. We hope to identify physical drivers resulting in the development of distinct geomorphic stream types and predict where the relative abundance of those stream types are likely to exist in arid environments of the southwestern U.S. We posit that locations and relative distributions of the five stream types will correlate significantly to local basin characteristics. Initial findings verify that composition of confining material dictates the level of confinement and largely influences occurrence of the five channel types. Additionally, we expect to see significant differences in width/depth ratios, grain size, stream gradient, basin hillslope gradient

  6. Implications of fish-habitat relationships for designing restoration projects within channelized agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channelized headwater streams are common throughout agricultural watersheds in the Midwestern United States. Management of these streams focuses on drainage without consideration of the other ecosystem services they are capable of providing. Restoration of channelized agricultural headwater stream...

  7. Public Health Perspectives of Channelized and Unchannelized Headwater Streams in Central Ohio: A Case Study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Headwater streams constitute the majority of watersheds in the United States and many headwater streams in the midwest have been channelized for agricultural drainage. Public health implications of water chemistry and aquatic macroinvertebrates within channelized and unchannelized headwater streams ...

  8. Influence of instream habitat and water chemistry on amphibians within channelized agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The widespread use of stream channelization and subsurface tile drainage for draining agricultural fields has led to the development of numerous channelized agricultural headwater streams within agricultural watersheds of the Midwestern United States, Canada, and Europe. Channelized agricultural he...

  9. Conservation implications of amphibian habitat relationships within channelized agricultural headwater streams in the midwestern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The widespread use of stream channelization and subsurface tile drainage for removing water from agricultural fields has led to the development of numerous channelized agricultural headwater streams within agricultural watersheds of the Midwestern United States. Channelized agricultural headwater s...

  10. Antarctic ice streams and outflow channels on Mars

    USGS Publications Warehouse

    Lucchitta, B.K.

    2001-01-01

    New sonar images of the Antarctic sea floor reveal mega-scale glacial lineations that are strikingly similar to longitudinal flutes in martian outflow channels. The analogs suggest that ice moved through the martian channels in places and carved the flutes. The ice in martian channels may have moved like Antarctic ice streams on deformable debris saturated with water under high pore pressure. On Mars, water at the base of ice-filled channels may have come from residual water or melt water liberated during past warmer climates or higher heat flows.

  11. Multiple-channel Streaming Delivery for Omnidirectional Vision System

    NASA Astrophysics Data System (ADS)

    Iwai, Yoshio; Nagahara, Hajime; Yachida, Masahiko

    An omnidirectional vision is an imaging system that can capture a surrounding image in whole direction by using a hyperbolic mirror and a conventional CCD camera. This paper proposes a streaming server that can efficiently transfer movies captured by an omnidirectional vision system through the Internet. The proposed system uses multiple channels to deliver multiple movies synchronously. Through this method, the system enables clients to view the different direction of omnidirectional movies and also support the function to change the view are during playback period. Our evaluation experiments show that our proposed streaming server can effectively deliver multiple movies via multiple channels.

  12. Man-induced channel adjustment in Tennessee streams

    USGS Publications Warehouse

    Robbins, C.H.; Simon, Andrew

    1983-01-01

    Channel modifications in Tennessee, particularly in the western part, have led to large-scale instabilities in the channelized rivers and may have contributed to several bridge failures. These modifications, together with land-use practices, led to downcutting, headward erosion, downstream aggradation, accelerated scour, and bank instabilities. Changes in gradient by channel straightening caused more severe channel response than did dredging or clearing. Large-scale changes continue to occur in all the channelized rivers: the Obion River, its forks, and the South Fork Forked Deer River. However, the non-channelized Hatchie River in west Tennessee not only withstood the natural stresses imposed by the wet years of 1973 to 1975 but continues to exhibit characteristics of stability. Water-surface slope, the primary dependent variable, proved to be a sensitive and descriptive parameter useful in determining channel adjustment. Adjustments to man-induced increases in channel-slope are described by inverse exponential functions of the basic form S=ae(-b(t)); where ' S ' is some function describing channel-slope, ' t ' is the number of years since completion of channel work, and ' a ' and ' b ' are coefficients. Response times for the attainment of ' equilibrium ' channel slopes are a function of the magnitude and extent of the imposed modifications. The adjusted profile gradients attained by the streams following channelization are similar to the predisturbed profile gradients, where no alteration to channel length was made. Where the channels were straightened by constructing cut-offs, thus shortening channel length, then slope adjustments (reduction) proceed past the predisturbed profile gradients, to new profiles with lower gradients. (USGS)

  13. Similarities in fish-habitat relationships within channelized agricultural headwater streams in Ohio and Indiana

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channelized agricultural headwater streams are common throughout agricultural watersheds in the Midwestern United States. Understanding the fish-habitat relationships within these streams will provide information that can assist with developing restoration strategies for these degraded streams. We...

  14. Diel Variation in Dissolved Trace-Element Concentrations in Streams Draining Abandoned Mine Lands

    NASA Astrophysics Data System (ADS)

    Nimick, D. A.

    2001-12-01

    Substantial diel (24-hour) variations in dissolved trace-element concentrations have been measured during 20 different hourly sampling episodes at 14 sites on 9 streams draining historical mining areas in Montana. At all sites, concentrations of dissolved (0.1-um filtration) Cd, Mn, and Zn increased during the night, reaching maximum values shortly after sunrise; concentrations then decreased to minimum values during mid to late afternoon. Dissolved As concentrations exhibited the opposite temporal pattern, while variations in dissolved Cu concentrations were small and displayed no consistent pattern. Most sites were sampled during low-flow conditions, but two sampling episodes during snowmelt runoff at one site showed that similar diel variations occur during high flow. All sites had near neutral to slightly alkaline pH. Diel variations did not occur in two other acidic (pH of 4.0-5.5) streams. The magnitude of change during diel concentration cycles varied for each trace element. Zn and Mn concentrations exhibited the largest variation, with maximum concentrations ranging from 120 to 590 percent higher than minimum concentrations. Cd maximum concentrations were about 200 percent higher than minimum concentrations, whereas As maximum concentrations were 115 to 155 percent higher. Diel trace-element cycles appear to be independent of concentration magnitude, occurring over a wide range of concentrations: 5-44 ug/L As; 1-7 ug/L Cd, 18-609 ug/L Mn, and 2-4,940 ug/L Zn. Several chemical, physical, and biological processes potentially can explain diel dissolved-trace-element cycles. Temperature- and pH-dependent sorption reactions occurring on streambed material in the channel and hyporheic zone are considered the most likely mechanisms because of the strong similarity in the symmetry and magnitude of temporal plots of concentration, temperature, and pH. In addition, sorption processes can explain the simultaneous decrease in divalent metal concentrations during the

  15. Variations in heavy metal contamination of stream water and groundwater affected by an abandoned lead-zinc mine in Korea.

    PubMed

    Lee, Jin-Yong; Choi, Jung-Chan; Lee, Kang-Kun

    2005-09-01

    This study evaluated variations in heavy metal contamination of stream waters and groundwaters affected by an abandoned lead-zinc mine, where a rockfill dam for water storage will be built 11 km downstream. For these purposes, a total of 10 rounds of stream and groundwater samplings and subsequent chemical analyses were performed during 2002-2003. Results of an exploratory investigation of stream waters in 2000 indicated substantial contamination with heavy metals including zinc (Zn), iron (Fe) and arsenic (As) for at least 6 km downstream from the mine. Stream waters near the mine showed metal contamination as high as arsenic (As) 8,923 microg L(-1), copper (Cu) 616 microg L(-1), cadmium (Cd) 223 microg L(-1) and lead (Pb) 10,590 microg L(-1), which greatly exceeded the Korean stream water guidelines. Remediation focused on the mine tailing piles largely improved the stream water qualities. However, there have still been quality problems for the waters containing relatively high concentrations of As (6-174 microg L(-1)), Cd (1-46 microg L(-1)) and Pb (2-26 microg L(-1)). Rainfall infiltration into the mine tailing piles resulted in an increase of heavy metals in the stream waters due to direct discharge of waste effluent, while dilution of the contaminated stream waters improved the water quality due to mixing with metal free rain waters. Levels of As, Cu and chromium (Cr) largely decreased after heavy rain but that of Pb was rather elevated. The stream waters were characterized by high concentrations of calcium (Ca) and sulfate (SO(4)), which were derived from dissolution and leaching of carbonate and sulfide minerals. It was observed that the proportions of Ca and SO(4) increased while those of bicarbonate (HCO(3)) and sodium and potassium (Na+K) decreased after a light rainfall event. Most interestingly, the reverse was generally detected for the groundwaters. The zinc, being the metal mined, was the most dominant heavy metal in the groundwaters (1758

  16. Variations in heavy metal contamination of stream water and groundwater affected by an abandoned lead-zinc mine in Korea.

    PubMed

    Lee, Jin-Yong; Choi, Jung-Chan; Lee, Kang-Kun

    2005-09-01

    This study evaluated variations in heavy metal contamination of stream waters and groundwaters affected by an abandoned lead-zinc mine, where a rockfill dam for water storage will be built 11 km downstream. For these purposes, a total of 10 rounds of stream and groundwater samplings and subsequent chemical analyses were performed during 2002-2003. Results of an exploratory investigation of stream waters in 2000 indicated substantial contamination with heavy metals including zinc (Zn), iron (Fe) and arsenic (As) for at least 6 km downstream from the mine. Stream waters near the mine showed metal contamination as high as arsenic (As) 8,923 microg L(-1), copper (Cu) 616 microg L(-1), cadmium (Cd) 223 microg L(-1) and lead (Pb) 10,590 microg L(-1), which greatly exceeded the Korean stream water guidelines. Remediation focused on the mine tailing piles largely improved the stream water qualities. However, there have still been quality problems for the waters containing relatively high concentrations of As (6-174 microg L(-1)), Cd (1-46 microg L(-1)) and Pb (2-26 microg L(-1)). Rainfall infiltration into the mine tailing piles resulted in an increase of heavy metals in the stream waters due to direct discharge of waste effluent, while dilution of the contaminated stream waters improved the water quality due to mixing with metal free rain waters. Levels of As, Cu and chromium (Cr) largely decreased after heavy rain but that of Pb was rather elevated. The stream waters were characterized by high concentrations of calcium (Ca) and sulfate (SO(4)), which were derived from dissolution and leaching of carbonate and sulfide minerals. It was observed that the proportions of Ca and SO(4) increased while those of bicarbonate (HCO(3)) and sodium and potassium (Na+K) decreased after a light rainfall event. Most interestingly, the reverse was generally detected for the groundwaters. The zinc, being the metal mined, was the most dominant heavy metal in the groundwaters (1758

  17. Grazed Riparian Management and Stream Channel Response in Southeastern Minnesota (USA) Streams

    NASA Astrophysics Data System (ADS)

    Magner, Joseph A.; Vondracek, Bruce; Brooks, Kenneth N.

    2008-09-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response.

  18. Grazed riparian management and stream channel response in southeastern Minnesota (USA) streams

    USGS Publications Warehouse

    Magner, J.A.; Vondracek, B.; Brooks, K.N.

    2008-01-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response. ?? 2008 Springer Science+Business Media, LLC.

  19. Grazed riparian management and stream channel response in southeastern Minnesota (USA) streams.

    PubMed

    Magner, Joseph A; Vondracek, Bruce; Brooks, Kenneth N

    2008-09-01

    The U.S. Department of Agriculture-Natural Resources Conservation Service has recommended domestic cattle grazing exclusion from riparian corridors for decades. This recommendation was based on a belief that domestic cattle grazing would typically destroy stream bank vegetation and in-channel habitat. Continuous grazing (CG) has caused adverse environmental damage, but along cohesive-sediment stream banks of disturbed catchments in southeastern Minnesota, short-duration grazing (SDG), a rotational grazing system, may offer a better riparian management practice than CG. Over 30 physical and biological metrics were gathered at 26 sites to evaluate differences between SDG, CG, and nongrazed sites (NG). Ordinations produced with nonmetric multidimensional scaling (NMS) indicated a gradient with a benthic macroinvertebrate index of biotic integrity (IBI) and riparian site management; low IBI scores associated with CG sites and higher IBI scores associated with NG sites. Nongrazed sites were associated with reduced soil compaction and higher bank stability, as measured by the Pfankuch stability index; whereas CG sites were associated with increased soil compaction and lower bank stability, SDG sites were intermediate. Bedrock geology influenced NMS results: sites with carbonate derived cobble were associated with more stable channels and higher IBI scores. Though current riparian grazing practices in southeastern Minnesota present pollution problems, short duration grazing could reduce sediment pollution if managed in an environmentally sustainable fashion that considers stream channel response.

  20. Natural decrease of dissolved arsenic in a small stream receiving drainages of abandoned silver mines in Guanajuato, Mexico.

    PubMed

    Arroyo, Yann Rene Ramos; Muñoz, Alma Hortensia Serafín; Barrientos, Eunice Yanez; Huerta, Irais Rodriguez; Wrobel, Kazimierz; Wrobel, Katarzyna

    2013-11-01

    Arsenic release from the abandoned mines and its fate in a local stream were studied. Physicochemical parameters, metals/metalloids and arsenic species were determined. One of the mine drainages was found as a point source of contamination with 309 μg L(-1) of dissolved arsenic; this concentration declined rapidly to 10.5 μg L(-1) about 2 km downstream. Data analysis confirmed that oxidation of As(III) released from the primary sulfide minerals was favored by the increase of pH and oxidation reduction potential; the results obtained in multivariate approach indicated that self-purification of water was due to association of As(V) with secondary solid phase containing Fe, Mn, Ca.

  1. Sediment geochemistry of streams draining abandoned lead/zinc mines in central Wales - the Afon Twymyn

    NASA Astrophysics Data System (ADS)

    Byrne, P.; Reid, I.; Wood, P. J.

    2009-04-01

    Catchment disturbances occur at a range of spatial and temporal scales. Polluted discharge from abandoned metal mines and spoil heaps can persist for centuries after the closure of a mine and leave a legacy of heavy metal contamination in sediment systems. Following the decline of metal mining in Wales during the 20th century, there are over 1 300 abandoned metal mines, many of which discharge metal rich waters to river systems. In some cases these discharges have been occurring for over a century resulting in severe impacts on sediment quality. Poor sediment quality is likely to impede the achievement of 'good' chemical and ecological status for surface waters under the European Union Water Framework Directive. This paper examines the legacy of the Dylife lead/zinc mine (central Wales) on the Afon Twymyn and associated sedimentary, water quality and ecological characteristics; and highlights the importance of incorporating sediment quality in the overall assessment of river ecosystem status. Sediment heavy metal concentrations are elevated throughout the Afon Twymyn with metal concentrations upstream of Dylife mine exceeding values downstream by up to 260 times. Lead concentrations are up to 100 times greater than levels predicted to have deleterious effects on aquatic ecology (draft Environment Agency of England and Wales predicted effect level guidelines). At the mine site, 54% of lead, 53% of zinc, 52% of cadmium and 19% of copper exist in the easily exchangeable and carbonate-bound geochemical phases. These metal species are unstable and can be absorbed by aquatic organisms or released into solution given changes in pH, ionic strength, redox conditions and/or the concentration of complexing agents. Downstream of the mine, sediment metal concentrations decrease sharply however, there is an increase in the proportion found in more mobile geochemical phases. Metal levels remain elevated above background concentrations for at least 20 km from the point of

  2. Instream wood recruitment, channel complexity, and their relationship to stream ecology in forested headwater streams under alternative stable states

    NASA Astrophysics Data System (ADS)

    Livers, B.; Wohl, E.

    2015-12-01

    Human alteration to forests has had lasting effects on stream channels worldwide. Such land use changes affect how wood enters and is stored in streams as individual pieces and as logjams. Changes in wood recruitment affect the complexity and benefits wood can provide to the stream environment, such as zones of flow separation that store fine sediment and organic matter, increased nutrient processing, and greater habitat potential, which can enhance biota and cascade through stream-riparian ecosystems. Previous research in our study area shows that modern headwater streams flowing through old-growth, unmanaged forests have more wood than streams in young, managed forests, but does not explicitly evaluate how wood affects channel complexity or local ecology. 'Managed' refers to forests previously or currently exposed to human alteration. Alteration has long since ceased in some areas, but reduced wood loads in managed streams persist. Our primary objective was to quantify stream complexity metrics, with instream wood as a mediator, on streams across a gradient of management and disturbance histories in order to examine legacy effects of human alteration to forests. Data collected in the Southern Rocky Mountains include 24 2nd to 3rd order subalpine streams categorized into: old-growth unmanaged; younger, naturally disturbed unmanaged; and younger managed. We assessed instream wood loads and logjams and evaluated how they relate to channel complexity using a number of metrics, such as standard deviation of bed and banks, volume of pools, ratios of stream to valley lengths and stream to valley area, and diversity of substrate, gradient, and morphology. Preliminary results show that channel complexity is directly related to instream wood loads and is greatest in streams in old-growth. Related research in the field area indicates that streams with greater wood loads also have increased nutrient processing and greater abundance and diversity of aquatic insect predators.

  3. Distribution, speciation, and transport of mercury in stream-sediment, stream-water, and fish collected near abandoned mercury mines in southwestern Alaska, USA

    USGS Publications Warehouse

    Gray, J.E.; Theodorakos, P.M.; Bailey, E.A.; Turner, R.R.

    2000-01-01

    Concentrations of total Hg, Hg (II), and methylmercury were measured in stream-sediment, stream-water, and fish collected downstream from abandoned mercury mines in south-western Alaska to evaluate environmental effects to surrounding ecosystems. These mines are found in a broad belt covering several tens of thousands of square kilometers, primarily in the Kuskokwim River basin. Mercury ore is dominantly cinnabar (HgS), but elemental mercury (Hg(o)) is present in ore at one mine and near retorts and in streams at several mine sites. Approximately 1400 t of mercury have been produced from the region, which is approximately 99% of all mercury produced from Alaska. These mines are not presently operating because of low prices and low demand for mercury. Stream-sediment samples collected downstream from the mines contain as much as 5500 ??g/g Hg. Such high Hg concentrations are related to the abundance of cinnabar, which is highly resistant to physical and chemical weathering, and is visible in streams below mine sites. Although total Hg concentrations in the stream-sediment samples collected near mines are high, Hg speciation data indicate that concentrations of Hg (II) are generally less than 5%, and methylmercury concentrations are less than 1% of the total Hg. Stream waters below the mines are neutral to slightly alkaline (pH 6.8-8.4), which is a result of the insolubility of cinnabar and the lack of acid- generating minerals such as pyrite in the deposits. Unfiltered stream-water samples collected below the mines generally contain 500-2500 ng/l Hg; whereas, corresponding stream-water samples filtered through a 0.45-??m membrane contain less than 50 ng/l Hg. These stream-water results indicate that most of the Hg transported downstream from the mines is as finely- suspended material rather than dissolved Hg. Mercury speciation data show that concentrations of Hg (II) and methylmercury in stream-water samples are typically less than 22 ng/l, and generally less than

  4. Differences in instream wood characteristics between channelized and unchannelized agricultural headwater streams in central Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Instream wood is an important resource for stream biota because it provides cover for fishes, substrate for macroinvertebrates, and increases habitat diversity. However, current management of instream wood within channelized agricultural headwater streams (drainage ditches) involves removing instrea...

  5. Simple measures of channel habitat complexity predict transient hydraulic storage in streams

    EPA Science Inventory

    Stream thalweg depth profiles (along path of greatest channel depth) and woody debris tallies have recently become components of routine field procedures for quantifying physical habitat in national stream monitoring efforts. Mean residual depth, standard deviation of thalweg dep...

  6. Characteristics of instream wood within channelized agricultural headwater streams in the Midwestern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channelized agricultural headwater streams are a common feature within agricultural watersheds of the Midwestern United States. These small streams have been impacted by the physical and chemical habitat alterations incurred to facilitate agricultural drainage. Quantitative information on the instre...

  7. Importance of instream wood characteristics for developing restoration designs for channelized agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channelized agricultural headwater streams are a common feature within agricultural watersheds of the Midwestern United States. These small streams have been impacted by the physical and chemical habitat alterations incurred to facilitate agricultural drainage. Quantitative information on the instr...

  8. Influence of Gully Erosion Control on Amphibian and Reptile Communities within Riparian Zones of Channelized Streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian zones of streams in northwestern Mississippi have been impacted by agriculture, channelization, channel incision, and gully erosion. Riparian gully formation has resulted in the fragmentation of remnant riparian zones within agricultural watersheds. One widely used conservation practice for...

  9. A standardized sampling protocol for channel catfish in prairie streams

    USGS Publications Warehouse

    Vokoun, Jason C.; Rabeni, Charles F.

    2001-01-01

    Three alternative gears—an AC electrofishing raft, bankpoles, and a 15-hoop-net set—were used in a standardized manner to sample channel catfish Ictalurus punctatus in three prairie streams of varying size in three seasons. We compared these gears as to time required per sample, size selectivity, mean catch per unit effort (CPUE) among months, mean CPUE within months, effect of fluctuating stream stage, and sensitivity to population size. According to these comparisons, the 15-hoop-net set used during stable water levels in October had the most desirable characteristics. Using our catch data, we estimated the precision of CPUE and size structure by varying sample sizes for the 15-hoop-net set. We recommend that 11–15 repetitions of the 15-hoop-net set be used for most management activities. This standardized basic unit of effort will increase the precision of estimates and allow better comparisons among samples as well as increased confidence in management decisions.

  10. Evolution of Microbial “Streamer” Growths in an Acidic, Metal-Contaminated Stream Draining an Abandoned Underground Copper Mine

    PubMed Central

    Kay, Catherine M.; Rowe, Owen F.; Rocchetti, Laura; Coupland, Kris; Hallberg, Kevin B.; Johnson, D. Barrie

    2013-01-01

    A nine year study was carried out on the evolution of macroscopic “acid streamer” growths in acidic, metal-rich mine water from the point of construction of a new channel to drain an abandoned underground copper mine. The new channel became rapidly colonized by acidophilic bacteria: two species of autotrophic iron-oxidizers (Acidithiobacillus ferrivorans and “Ferrovum myxofaciens”) and a heterotrophic iron-oxidizer (a novel genus/species with the proposed name “Acidithrix ferrooxidans”). The same bacteria dominated the acid streamer communities for the entire nine year period, with the autotrophic species accounting for ~80% of the micro-organisms in the streamer growths (as determined by terminal restriction enzyme fragment length polymorphism (T-RFLP) analysis). Biodiversity of the acid streamers became somewhat greater in time, and included species of heterotrophic acidophiles that reduce ferric iron (Acidiphilium, Acidobacterium, Acidocella and gammaproteobacterium WJ2) and other autotrophic iron-oxidizers (Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans). The diversity of archaea in the acid streamers was far more limited; relatively few clones were obtained, all of which were very distantly related to known species of euryarchaeotes. Some differences were apparent between the acid streamer community and planktonic-phase bacteria. This study has provided unique insights into the evolution of an extremophilic microbial community, and identified several novel species of acidophilic prokaryotes. PMID:25371339

  11. Rain and channel flow supplements to subsurface water beneath hyper-arid ephemeral stream channels

    NASA Astrophysics Data System (ADS)

    Kampf, Stephanie K.; Faulconer, Joshua; Shaw, Jeremy R.; Sutfin, Nicholas A.; Cooper, David J.

    2016-05-01

    In hyper-arid regions, ephemeral stream channels are important sources of subsurface recharge and water supply for riparian vegetation, but few studies have documented the subsurface water content dynamics of these systems. This study examines ephemeral channels in the hyper-arid western Sonoran Desert, USA to determine how frequently water recharges the alluvial fill and identify variables that affect the depth and persistence of recharge. Precipitation, stream stage, and subsurface water content measurements were collected over a three-year study at six channels with varying contributing areas and thicknesses of alluvial fill. All channels contain coarse alluvium composed primarily of sands and gravels, and some locations also have localized layers of fine sediment at 2-3 m depth. Rain alone contributed 300-400 mm of water input to these channels over three years, but water content responses were only detected for 36% of the rain events at 10 cm depth, indicating that much of the rain water was either quickly evaporated or taken up by plants. Pulses of water from rain events were detected only in the top meter of alluvium. The sites each experienced ⩽5 brief flow events, which caused transient saturation that usually lasted only a few hours longer than flow. These events were the only apparent source of water to depths >1 m, and water from flow events quickly percolated past the deepest measurement depths (0.5-3 m). Sustained saturation in the shallow subsurface only developed where there was a near-surface layer of finer consolidated sediments that impeded deep percolation.

  12. Long-term impacts of land cover changes on stream channel loss

    EPA Science Inventory

    Land cover change and stream channel loss are two related global environmental changes that are expanding and intensifying. Here, we examine how different types and transitions of land cover change impact stream channel loss across a large urbanizing watershed with large areas of...

  13. Sensitivity of Off-Channel Salmon Rearing Habitats to Changing Base Flows in Low-Gradient Reaches of Central Idaho Mountain Streams

    NASA Astrophysics Data System (ADS)

    McKean, J. A.; Thurow, R.; Tonina, D.; Isaak, D.; Bohn, C.

    2010-12-01

    Critical rearing habitats for juvenile salmon and trout are frequently in off-channel areas of shallow, low-velocity water. Typically, these are remnants of abandoned channel positions that are still hydraulically connected to the contemporary main channel. However, the size and spatial arrangement of this habitat is strongly dependent on water stage in the main channel. In two salmon-bearing streams in the Middle Fork Salmon River, Idaho, we used a high-resolution channel DEM and a 1D fluid dynamics model to define the location, depth, total area, frequency, and timing and duration of flooding of off-channel habitat. We then predicted changes in water surface elevation in the main channel over a range of low flow discharges and remapped the functional off-channel areas at each flow stage. Measurements at nearby gages indicate that average late summer and autumn low flows in these streams have declined by about 7% per decade over the prior 60 years. Modern off-channel habitat along the 20km of study streams is not uniformly arranged, even at high flows, and the distribution becomes still more restricted in space and time as flows decline. Progeny of summer- and early fall-spawning Chinook salmon rear for up to 2 years in these streams before migrating to the ocean, with much of that time spent in the off-channel habitat. Progeny of spring-spawning steelhead use the same areas for up to 3 years. While much prior research has focused on the effects of climate change on the availability and condition of spawning sites and on water temperatures, this study documents likely changes in the amount and condition of rearing habitat. Further investigation is needed to understand the ecological consequences and whether the declining anadromous fish populations may be at some risk from diminishing rearing habitat during declining base flows caused by external forces, such as a changing climate, dams, or water extractions.

  14. Groundwater exchanges near a channelized versus unmodified stream mouth discharging to a subalpine lake

    NASA Astrophysics Data System (ADS)

    Constantz, J.; Naranjo, R.; Niswonger, R.; Allander, K.; Neilson, B.; Rosenberry, D.; Smith, D.; Rosecrans, C.; Stonestrom, D.

    2016-03-01

    The terminus of a stream flowing into a larger river, pond, lake, or reservoir is referred to as the stream-mouth reach or simply the stream mouth. The terminus is often characterized by rapidly changing thermal and hydraulic conditions that result in abrupt shifts in surface water/groundwater (sw/gw) exchange patterns, creating the potential for unique biogeochemical processes and ecosystems. Worldwide shoreline development is changing stream-lake interfaces through channelization of stream mouths, i.e., channel straightening and bank stabilization to prevent natural meandering at the shoreline. In the central Sierra Nevada (USA), Lake Tahoe's shoreline has an abundance of both "unmodified" (i.e., not engineered though potentially impacted by broader watershed engineering) and channelized stream mouths. Two representative stream mouths along the lake's north shore, one channelized and one unmodified, were selected to compare and contrast water and heat exchanges. Hydraulic and thermal properties were monitored during separate campaigns in September 2012 and 2013 and sw/gw exchanges were estimated within the stream mouth-shoreline continuum. Heat-flow and water-flow patterns indicated clear differences in the channelized versus the unmodified stream mouth. For the channelized stream mouth, relatively modulated, cool-temperature, low-velocity longitudinal streambed flows discharged offshore beneath warmer buoyant lakeshore water. In contrast, a seasonal barrier bar formed across the unmodified stream mouth, creating higher-velocity subsurface flow paths and higher diurnal temperature variations relative to shoreline water. As a consequence, channelization altered sw/gw exchanges potentially altering biogeochemical processing and ecological systems in and near the stream mouth.

  15. Groundwater exchanges near a channelized versus unmodified stream mouth discharging to a subalpine lake

    USGS Publications Warehouse

    Constantz, James; Naranjo, Ramon C.; Niswonger, Richard; Allander, Kip K.; Neilson, B.; Rosenberry, Donald O.; Smith, David W.; Rosecrans, C.; Stonestrom, David A.

    2016-01-01

    The terminus of a stream flowing into a larger river, pond, lake, or reservoir is referred to as the stream-mouth reach or simply the stream mouth. The terminus is often characterized by rapidly changing thermal and hydraulic conditions that result in abrupt shifts in surface water/groundwater (sw/gw) exchange patterns, creating the potential for unique biogeochemical processes and ecosystems. Worldwide shoreline development is changing stream-lake interfaces through channelization of stream mouths, i.e., channel straightening and bank stabilization to prevent natural meandering at the shoreline. In the central Sierra Nevada (USA), Lake Tahoe's shoreline has an abundance of both “unmodified” (i.e., not engineered though potentially impacted by broader watershed engineering) and channelized stream mouths. Two representative stream mouths along the lake's north shore, one channelized and one unmodified, were selected to compare and contrast water and heat exchanges. Hydraulic and thermal properties were monitored during separate campaigns in September 2012 and 2013 and sw/gw exchanges were estimated within the stream mouth-shoreline continuum. Heat-flow and water-flow patterns indicated clear differences in the channelized versus the unmodified stream mouth. For the channelized stream mouth, relatively modulated, cool-temperature, low-velocity longitudinal streambed flows discharged offshore beneath warmer buoyant lakeshore water. In contrast, a seasonal barrier bar formed across the unmodified stream mouth, creating higher-velocity subsurface flow paths and higher diurnal temperature variations relative to shoreline water. As a consequence, channelization altered sw/gw exchanges potentially altering biogeochemical processing and ecological systems in and near the stream mouth.

  16. Long-term impacts of land cover changes on stream channel loss.

    PubMed

    Julian, Jason P; Wilgruber, Nicholas A; de Beurs, Kirsten M; Mayer, Paul M; Jawarneh, Rana N

    2015-12-15

    Land cover change and stream channel loss are two related global environmental changes that are expanding and intensifying. Here, we examine how different types and transitions of land cover change impact stream channel loss across a large urbanizing watershed. We present historical land cover in the 666-km(2) Lake Thunderbird watershed in central Oklahoma (USA) over a 137 year period and coinciding stream channel length changes for the most recent 70 years of this period. Combining these two datasets allowed us to assess the interaction of land cover changes with stream channel loss. Over this period, the upper third of the watershed shifted from predominantly native grassland to an agricultural landscape, followed by widespread urbanization. The lower two-thirds of the watershed changed from a forested landscape to a mosaic of agriculture, urban, forest, and open water. Most channel length lost in the watershed over time was replaced by agriculture. Urban development gradually increased channel loss and disconnection from 1942 to 2011, particularly in the headwaters. Intensities of channel loss for both agriculture and urban increased over time. The two longest connected segments of channel loss came from the creation of two large impoundments, resulting in 46 km and 25 km of lost stream channel, respectively. Overall, the results from this study demonstrate that multiple and various land-use changes over long time periods can lead to rapid losses of large channel lengths as well as gradual (but increasing) losses of small channel lengths across all stream sizes. When these stream channel losses are taken into account, the environmental impacts of anthropogenic land-use change are compounded. PMID:26282774

  17. West-Antarctic Ice Streams: Analog to Ice Flow in Channels on Mars

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1997-01-01

    Sounding of the sea floor in front of the Ross Ice Shelf in Antarctica recently revealed large persistent patterns of longitudinal megaflutes and drumlinoid forms, which are interpreted to have formed at the base of ice streams during the list glacial advance. The flutes bear remarkable resemblance to longitudinal grooves and highly elongated streamlined islands found on the floors of some large martian channels, called outflow channels. ln addition, other similarities exist between Antarctic ice streams and outflow channels. Ice streams are 30 to 80 km wide and hundreds of kilometers long, as are the martian channels. Ice stream beds are below sea level. Floors of many martian outflow channels lie below martian datum, which may have been close to or below past martian sea levels. The Antarctic ice stream bed gradient is flat and locally may go uphill, and surface slopes are exceptionally low. So are gradients of martian channels. The depth to the bed in ice streams is 1 to 1.5 km. At bankful stage, the depth of the fluid in outflow channels would have been 1 to 2 km. These similarities suggest that the martian outflow channels, whose origin is commonly attributed to gigantic catastrophic floods, were locally filled by ice that left a conspicuous morphologic imprint. Unlike the West-Antarctic-ice streams, which discharge ice from an ice sheet, ice in the martian channels came from water erupting from the ground. In the cold martian environment, this water, if of moderate volume, would eventually freeze. Thus it may have formed icings on springs, ice dams and jams on constrictions in the channel path, or frozen pools. Given sufficient thickness and downhill surface gradient, these ice masses would have moved; and given the right conditions, they could have moved like Antarctic ice streams.

  18. Instream Wood Loads and Channel Complexity in Headwater Streams Under Alternative Stable States

    NASA Astrophysics Data System (ADS)

    Livers, B.; Wohl, E.

    2014-12-01

    Channel morphology and irregularities in stream boundaries can create zones of flow separation, where lower velocities trap fine sediment and organic matter and increase opportunities for nutrient processing and biological uptake. This effect is most pronounced with channel-spanning structures such as logjams. Humans have changed the spatial and temporal characteristics of wood distribution in streams, with lasting effects on instream wood recruitment, wood loads, logjam distribution, and hydraulic roughness. Previous studies in the Colorado Front Range show that contemporary headwater streams flowing through old-growth, unmanaged forests have more wood than streams flowing through younger-growth, managed forests, but do not evaluate the effects of wood on channel complexity. 'Managed' versus 'unmanaged' refers to whether forests were or are currently exposed to human alteration. Although some alteration has long since ceased, reduced wood loads in managed streams persist. Our primary objective was to quantify differences in logjams, wood volumes, stream complexity, and organic carbon storage on streams with different management and disturbance histories in order to examine legacy effects across a gradient of stream management. Data were collected during the summers of 2013 and 2014 in the Southern Rocky Mountains. The 25 stream reaches studied are 2nd to 3rd order, subalpine streams that are categorized into: old-growth unmanaged forests; younger, naturally disturbed unmanaged forests; and younger managed forests. We assessed instream and floodplain wood loads and logjams and evaluated the role that large wood plays in local channel complexity, pool volume, and storage of organic carbon. Preliminary results show that greatest wood and carbon storage in sediments, as well as channel complexity, occurs in streams in old-growth, unmanaged forests and the least wood and carbon storage and channel complexity occurs in younger-growth, managed forests.

  19. Channel stability downstream from a dam assessed using aerial photographs and stream-gage information

    USGS Publications Warehouse

    Juracek, K.E.

    2000-01-01

    The stability of the Neosho River channel downstream from John Redmond Dam, in southeast Kansas, was investigated using multiple-date aerial photographs and stream-gage information. Bankfull channel width was used as the primary indicator variable to assess pre- and post-dam channel change. Five six-mile river reaches and four stream gages were used in the analysis. Results indicated that, aside from some localized channel widening, the overall channel change has been minor with little post-dam change in bankfull channel width. The lack of a pronounced postdam channel change may be attributed to a substantial reduction in the magnitude of the post-dam annual peak discharges in combination with the resistance to erosion of the bed and bank materials. Also, the channel may have been overwidened by a series of large floods that predated construction of the dam, including one with an estimated 500-year recurrence interval.

  20. Distinctive channel geometry and riparian vegetation: A geomorphic classification for arid ephemeral streams

    NASA Astrophysics Data System (ADS)

    Sutfin, N.; Shaw, J. R.; Wohl, E. E.; Cooper, D.

    2012-12-01

    Interactions between hydrology, channel form, and riparian vegetation along arid ephemeral streams are not thoroughly understood and current stream classifications do not adequately represent variability in channel geometry and associated riparian communities. Relatively infrequent hydrologic disturbances in dryland environments are responsible for creation and maintenance of channel form that supports riparian communities. To investigate the influence of channel characteristics on riparian vegetation in the arid southwestern United States, we develop a geomorphic classification for arid ephemeral streams based on the degree of confinement and the composition of confining material that provide constraints on available moisture. Our conceptual model includes five stream types: 1) bedrock channels entirely confined by exposed bedrock and devoid of persistent alluvium; 2) bedrock with alluvium channels at least partially confined by bedrock but containing enough alluvium to create bedforms that persist through time; 3) incised alluvium channels bound only by unconsolidated alluvial material into which they are incised; 4) braided washes that exhibit multi-thread, braided characteristics regardless of the composition of confining material; and 5) piedmont headwater 0-2nd order streams (Strahler) confined only by unconsolidated alluvium and which initiate as secondary channels on piedmont surfaces. Eighty-six study reaches representing the five stream types were surveyed on the U.S. Army Yuma Proving Ground in the Sonoran Desert of southwestern Arizona. Non-parametric multivariate analysis of variance (PERMANOVA) indicates significant differences between the five stream types with regards to channel geometry (i.e., stream gradient, width-to-depth ratio, the ratio between valley width and channel width (Wv/Wc), shear stress, and unit stream power) and riparian vegetation (i.e., presence and canopy coverage by species, canopy stratum, and life form). Discriminant analysis

  1. Computer-aided mapping of stream channels beneath the Lawrence Livermore National Laboratory Super Fund Site

    SciTech Connect

    Sick, M.

    1994-12-01

    The Lawrence Livermore National Laboratory (LLNL) site rests upon 300-400 feet of highly heterogeneous braided stream sediments which have been contaminated by a plume of Volatile Organic Compounds (VOCs). The stream channels are filled with highly permeable coarse grained materials that provide quick avenues for contaminant transport. The plume of VOCs has migrated off site in the TFA area, making it the area of greatest concern. I mapped the paleo-stream channels in the TFA area using SLICE an LLNL Auto-CADD routine. SLICE constructed 2D cross sections and sub-horizontal views of chemical, geophysical, and lithologic data sets. I interpreted these 2D views as a braided stream environment, delineating the edges of stream channels. The interpretations were extracted from Auto-CADD and placed into Earth Vision`s 3D modeling and viewing routines. Several 3D correlations have been generated, but no model has yet been chosen as a best fit.

  2. The importance of instream habitat modifications for restoring channelized agricultural headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Science based information on the influence of restoration practices on fishes within channelized agricultural headwater streams in the Midwestern United States is currently lacking. Understanding fish-habitat relationships and fish responses to specific restoration practices will provide informatio...

  3. HOW WELL CAN YOU ESTIMATE LOW FLOW AND BANKFULL DISCHARGE FROM STREAM CHANNEL HABITAT DATA?

    EPA Science Inventory

    Modeled estimates of stream discharge are becoming more important because of reductions in the number of gauging stations and increases in flow alteration from land development and climate change. Field measurements of channel morphology are available at thousands of streams and...

  4. Rock riprap design for protection of stream channels near highway structures; Volume 1, Hydraulic characteristics of open channels

    USGS Publications Warehouse

    Blodgett, J.C.

    1986-01-01

    Volume I discusses the hydraulic and channel properties of streams, based on data from several hundred sites. Streamflow and geomorphic data have been collected and developed to indicate the range in hydraulic factors typical of open channels , to assist design, maintenance, and construction engineers in preparing rock riprap bank protection. Typical channels were found to have maximum-to-mean depth ratio of 1.55 and a ratio of hydraulic radius to mean depth of 0.98, which is independent of width. Most stable channel characteristics for a given discharge are slope, maximum depth, and hydraulic radius. (See also W89-04911) (Author 's abstract)

  5. The Blurred Line between Form and Process: A Comparison of Stream Channel Classification Frameworks

    PubMed Central

    Kasprak, Alan; Hough-Snee, Nate

    2016-01-01

    Stream classification provides a means to understand the diversity and distribution of channels and floodplains that occur across a landscape while identifying links between geomorphic form and process. Accordingly, stream classification is frequently employed as a watershed planning, management, and restoration tool. At the same time, there has been intense debate and criticism of particular frameworks, on the grounds that these frameworks classify stream reaches based largely on their physical form, rather than direct measurements of their component hydrogeomorphic processes. Despite this debate surrounding stream classifications, and their ongoing use in watershed management, direct comparisons of channel classification frameworks are rare. Here we implement four stream classification frameworks and explore the degree to which each make inferences about hydrogeomorphic process from channel form within the Middle Fork John Day Basin, a watershed of high conservation interest within the Columbia River Basin, U.S.A. We compare the results of the River Styles Framework, Natural Channel Classification, Rosgen Classification System, and a channel form-based statistical classification at 33 field-monitored sites. We found that the four frameworks consistently classified reach types into similar groups based on each reach or segment’s dominant hydrogeomorphic elements. Where classified channel types diverged, differences could be attributed to the (a) spatial scale of input data used, (b) the requisite metrics and their order in completing a framework’s decision tree and/or, (c) whether the framework attempts to classify current or historic channel form. Divergence in framework agreement was also observed at reaches where channel planform was decoupled from valley setting. Overall, the relative agreement between frameworks indicates that criticism of individual classifications for their use of form in grouping stream channels may be overstated. These form

  6. The Blurred Line between Form and Process: A Comparison of Stream Channel Classification Frameworks.

    PubMed

    Kasprak, Alan; Hough-Snee, Nate; Beechie, Tim; Bouwes, Nicolaas; Brierley, Gary; Camp, Reid; Fryirs, Kirstie; Imaki, Hiroo; Jensen, Martha; O'Brien, Gary; Rosgen, David; Wheaton, Joseph

    2016-01-01

    Stream classification provides a means to understand the diversity and distribution of channels and floodplains that occur across a landscape while identifying links between geomorphic form and process. Accordingly, stream classification is frequently employed as a watershed planning, management, and restoration tool. At the same time, there has been intense debate and criticism of particular frameworks, on the grounds that these frameworks classify stream reaches based largely on their physical form, rather than direct measurements of their component hydrogeomorphic processes. Despite this debate surrounding stream classifications, and their ongoing use in watershed management, direct comparisons of channel classification frameworks are rare. Here we implement four stream classification frameworks and explore the degree to which each make inferences about hydrogeomorphic process from channel form within the Middle Fork John Day Basin, a watershed of high conservation interest within the Columbia River Basin, U.S.A. We compare the results of the River Styles Framework, Natural Channel Classification, Rosgen Classification System, and a channel form-based statistical classification at 33 field-monitored sites. We found that the four frameworks consistently classified reach types into similar groups based on each reach or segment's dominant hydrogeomorphic elements. Where classified channel types diverged, differences could be attributed to the (a) spatial scale of input data used, (b) the requisite metrics and their order in completing a framework's decision tree and/or, (c) whether the framework attempts to classify current or historic channel form. Divergence in framework agreement was also observed at reaches where channel planform was decoupled from valley setting. Overall, the relative agreement between frameworks indicates that criticism of individual classifications for their use of form in grouping stream channels may be overstated. These form

  7. The Blurred Line between Form and Process: A Comparison of Stream Channel Classification Frameworks.

    PubMed

    Kasprak, Alan; Hough-Snee, Nate; Beechie, Tim; Bouwes, Nicolaas; Brierley, Gary; Camp, Reid; Fryirs, Kirstie; Imaki, Hiroo; Jensen, Martha; O'Brien, Gary; Rosgen, David; Wheaton, Joseph

    2016-01-01

    Stream classification provides a means to understand the diversity and distribution of channels and floodplains that occur across a landscape while identifying links between geomorphic form and process. Accordingly, stream classification is frequently employed as a watershed planning, management, and restoration tool. At the same time, there has been intense debate and criticism of particular frameworks, on the grounds that these frameworks classify stream reaches based largely on their physical form, rather than direct measurements of their component hydrogeomorphic processes. Despite this debate surrounding stream classifications, and their ongoing use in watershed management, direct comparisons of channel classification frameworks are rare. Here we implement four stream classification frameworks and explore the degree to which each make inferences about hydrogeomorphic process from channel form within the Middle Fork John Day Basin, a watershed of high conservation interest within the Columbia River Basin, U.S.A. We compare the results of the River Styles Framework, Natural Channel Classification, Rosgen Classification System, and a channel form-based statistical classification at 33 field-monitored sites. We found that the four frameworks consistently classified reach types into similar groups based on each reach or segment's dominant hydrogeomorphic elements. Where classified channel types diverged, differences could be attributed to the (a) spatial scale of input data used, (b) the requisite metrics and their order in completing a framework's decision tree and/or, (c) whether the framework attempts to classify current or historic channel form. Divergence in framework agreement was also observed at reaches where channel planform was decoupled from valley setting. Overall, the relative agreement between frameworks indicates that criticism of individual classifications for their use of form in grouping stream channels may be overstated. These form

  8. Influence of Beaver Dams on Channel Complexity, Hydrology, and Temperature Regime in a Mountainous Stream

    NASA Astrophysics Data System (ADS)

    Majerova, M.; Neilson, B. T.; Schmadel, N. M.; Wheaton, J. M.; Snow, C. J.

    2013-12-01

    Beaver dams and beaver activity affect hydrologic processes, sediment transport, channel complexity and water quality of streams. Beaver ponds, which form behind beaver dams, increase in-channel water storage affecting the timing and volume of flow and resulting in the attenuation and flattening of the hydrograph. Channel complexity also increases the potential for transient storage (both surface and subsurface) and influences stream temperature. Impacts of beaver dams and beaver activity on stream responses are difficult to quantify because responses are dynamic and spatially variable. Few studies have focused on the reach scale temporal influences on stream responses and further research is needed particularly in quantifying the influence of beaver dams and their role in shaping the stream habitat. This study explores the changing hydrology and temperature regime of Curtis Creek, a mountainous stream located in Northern Utah, in a 560 m long reach where groundwater exchanges and temperature differences were observed over a three-year period. We have collected continuous stream discharge, stream temperature data and performed tracer experiments. During the first year, we were able to capture the pre-beaver activity. In the second year, we captured the impacts of some beaver activity with only a few dams built in the reach, while the third year included the effects of an entire active beaver colony. By the end of the study period, a single thread channel had been transformed into a channel with side channels and backwaters at multiple locations therefore increasing channel complexity. The cumulative influence of beaver dams on reach scale discharge resulted in a slightly losing reach that developed into a gaining reach. At the smaller sub-reach scale, both losing to gaining and gaining to losing transformations were observed. Temperature differences showed a warming effect of beaver dams at the reach scale. The reach stream temperature difference increased on

  9. Hydroclimatic signal and LBK cultural activity in the Upper and Lower Rhine, inferred from abandoned channel fill deposits

    NASA Astrophysics Data System (ADS)

    Berger, J. F.; Salvador, P. G.; Erkens, G.; Toonen, W. H. J.; Purdue, L.; Barra, A.; Houben, P.

    2012-04-01

    The Linear Band Ceramic (LBK) culture represents a major event in the spread of agriculture in Europe. Occupation particularly occurred in river valleys, with largest densities found along the rivers Danube, Elbe and Rhine. The interaction between the emergence of this culture and the dominant climatic and hydrological conditions is not yet fully established. As part of the ANR OBRESOC project, in which LBK activity is investigated in a transect from France (Marne river) to the catchment of the Danube river (Tisza), we studied palaeo-environmental changes in the Rhine valley between 7600-6600 cal. yrs. BP. Focus is on the Upper Rhine Graben and the Lower Rhine valley near the Rhine Delta apex, which is thought to be a peripheral region of LBK-activity. In these regions, a total of five cores from abandoned channels were analysed to reconstruct palaeo-environmental dynamics in vegetation and fluvial activity during the period of LBK development. Abandoned channel fills are excellent sites to perform detailed studies of palaeo-environmental dynamics, as they (i) form proximal locations to occupation sites of the LBK culture, (ii) act as efficient traps of sediments in which different environmental proxies are well preserved, (iii) contain well-datable material for the construction of detailed age-depth models, and (iv) provide a long proxy record, potentially over more than a millennium at a single site. On all cores, high resolution analysis of channel fill deposits (grain size and geophysical properties) and biotic proxies (micro-charcoal fluxes and pollen assemblages) were preformed to reconstruct palaeo-environmental signals, such as changes in fluvial activity, forest fires, and vegetation evolution, which may be related to agricultural activity, and climatic and hydrogeomorphic changes in the region. In this contribution we compare the results of the high-resolution core analyses (1,5 to 5m sequences for the studied timeframe) derived from the more densely

  10. Influences of Hardwood Riparian Vegetation on Stream Channel Geometry in Eastern Forested Environments

    NASA Astrophysics Data System (ADS)

    Cohen, L. J.; Furbish, D. J.

    2015-12-01

    Riparian vegetation has been recognized as a controlling factor of stream channel morphology, but specific influences on bed topography and planform geometry are yet to be fully clarified. In temperate environments, hardwood trees serve as prominent bank stabilizers and help create diverse habitats for a variety of aquatic organisms in alluvial channels. This project explores the influence of riparian vegetation on channel geometry in alluvial streams of different sizes. Exposed rootwads increase bank stability and slow channel migration rates, but also cause pool scour that affects thalweg and bedform locations downstream, implying that woody riparian vegetation influences flow conditions and two-dimensional bed geometry in alluvial streams. Field data suggest that the presence of hardwood vegetation modulates channel width, bed topography and planform geometry in low-order streams. In larger channels, rootwads have less influence on planform curvature, but create patchy variations in bed topography that establish thalweg locations and amplify relief of curvature-dominated bedforms. Flume experiments illustrate the genesis of rootwad-induced pool scour and its effect on downstream pool and bar formation. Experimental rootwad pools reflect the relative size and shape of those observed in natural channels. Introduction of riparian obstructions to planar beds also influences thalweg location several channel widths downstream, further supporting the idea of riparian influence on bedform modulation and regulation.

  11. Influence of gully erosion control on amphibian and reptile communities within riparian zones of channelized streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Riparian zones of streams in northern Mississippi have been impacted by agriculture, channelization, channel incision, and gully erosion. Gully erosion is the most severe form of erosion and has resulted in the fragmentation of remnant riparian zones within agricultural watersheds. One widely used c...

  12. Regional impacts of urbanization on stream channel geometry: A case study in semiarid southern California

    NASA Astrophysics Data System (ADS)

    Taniguchi, Kristine T.; Biggs, Trent W.

    2015-11-01

    Urbanization often increases storm runoff, peak discharges and rates of stream channel erosion. Coastal California has experienced rapid urbanization over the past several decades and has the potential for stream channel degradation. Several counties in California have implemented Hydromodification Management Plans (HMPs) to protect channels from erosion, but few studies have quantified the impact of urbanization on channel geometry in diverse geological settings at the county scale. A synoptic survey of field sites (N = 56) by the California Environmental Data Exchange Network (CEDEN) and additional field surveys (N = 24) were used to develop regional hydraulic geometry curves relating bankfull cross-sectional area (Axs), width (w), mean depth (d), and discharge (Qbf) to watershed area (Aw) in San Diego County. Regional curves were compared for urban and reference sites and to other regional curves developed for southern California. Multiple regression models were used to identify dominant watershed and channel controls on geometry, including Aw, percent impervious cover (I%), mean annual precipitation, underlying geology, longitudinal slope, hydrologic soil group, and channel particle size. For the reference streams, regional curves were statistically significant for w and Axs (p < 0.05). The regional curves for urban channels (I% > 20%) had significantly larger w, d, Axs, and Qbf for a given watershed size. A majority (68%) of the urban channels and 78% of the small urban channels (Aw < 10 km2) were enlarged. Enlargement of channels in small watersheds disrupted the correlation between Aw and bankfull dimensions, and I% was the only significant predictor of channel geometry in urban watersheds. Channel response differed by channel substrate: sand-bedded channels incised and experienced extreme enlargement of up to 115 × the Axs of reference sites, while gravel-bedded channels widened and showed less enlargement (< 7 × reference Axs). Diverse channel responses

  13. In situ production of methylmercury within a stream channel in northern California.

    PubMed

    Tsui, Martin Tsz Ki; Finlay, Jacques C; Balogh, Steven J; Nollet, Yabing H

    2010-09-15

    Natural stream ecosystems throughout the world are contaminated by methylmercury, a highly toxic compound that bioaccumulates and biomagnifies in aquatic food webs. Wetlands are widely recognized as hotspots for the production of methylmercury and are often assumed to be the main sources of this neurotoxin in downstream ecosystems. However, many streams lacking wetlands in their drainage basins (e.g., montane and semiarid regions in the western United States) have significant methylmercury contamination, and the sources of methylmercury in these streams remain largely unknown. In this study, we observed substantial production of methylmercury within a highly productive stream channel in northern California (South Fork Eel River) within a drainage basin lacking wetlands. We found that in situ methylmercury production is positively related to phosphorus removal and water temperature within the stream channel, supporting hypothesized biological mediation of in situ mercury transformation. Moreover, our data suggest that epiphytic microbial communities on a dominant filamentous alga (Cladophora glomerata) could play a role in in situ methylmercury production. Because peak in situ methylmercury production coincides with the period of the highest biological productivity during summer baseflow, methylmercury produced internally may be efficiently routed into local stream food webs. Our study provides strong evidence that stream channels, especially those associated with high primary productivity, can be important for regulating the bioavailability and toxicity of this global contaminant. PMID:20715863

  14. In situ production of methylmercury within a stream channel in northern California.

    PubMed

    Tsui, Martin Tsz Ki; Finlay, Jacques C; Balogh, Steven J; Nollet, Yabing H

    2010-09-15

    Natural stream ecosystems throughout the world are contaminated by methylmercury, a highly toxic compound that bioaccumulates and biomagnifies in aquatic food webs. Wetlands are widely recognized as hotspots for the production of methylmercury and are often assumed to be the main sources of this neurotoxin in downstream ecosystems. However, many streams lacking wetlands in their drainage basins (e.g., montane and semiarid regions in the western United States) have significant methylmercury contamination, and the sources of methylmercury in these streams remain largely unknown. In this study, we observed substantial production of methylmercury within a highly productive stream channel in northern California (South Fork Eel River) within a drainage basin lacking wetlands. We found that in situ methylmercury production is positively related to phosphorus removal and water temperature within the stream channel, supporting hypothesized biological mediation of in situ mercury transformation. Moreover, our data suggest that epiphytic microbial communities on a dominant filamentous alga (Cladophora glomerata) could play a role in in situ methylmercury production. Because peak in situ methylmercury production coincides with the period of the highest biological productivity during summer baseflow, methylmercury produced internally may be efficiently routed into local stream food webs. Our study provides strong evidence that stream channels, especially those associated with high primary productivity, can be important for regulating the bioavailability and toxicity of this global contaminant.

  15. Do the coarsest bed fractions and stream power record contemporary trends in steep headwater channels?

    NASA Astrophysics Data System (ADS)

    Galia, Tomáš; Škarpich, Václav

    2016-11-01

    Three stream channels that were devoid of evidence of past debris flows and one headwater channel that contained debris flow deposits in the flysch western Carpathians, Czech Republic were selected to test relationships between in-channel processes, bed sediments, and unit stream power calculated for bankfull and Q20 flows. Contemporary depositional or erosional trends in the examined headwaters were linked with bed sediments that were represented by the coarsest cobble and boulder fraction with a mean calculated from the five largest particles. The downstream trends of the unit stream power were derived for a bankfull discharge and a well-documented 20-year flood event. In addition, the flow competences during the discharges were calculated using indirect bedload transport measurements. Downstream fining of the cobble and boulder fraction was observed in all of the studied headwaters, and unique downstream variations of the unit stream power were calculated for the longitudinal profiles. The single-thread streams that were devoid of evidence of debris flow events exhibited direct relations between the coarsest sediment size and the unit stream power, especially as calculated for the 20-year flood event and for erosional/depositional trends of the channel. The downstream coarsening of the bed material that was accompanied by an increase in the unit stream power was usually observed in the case of deeply incised (> 0.5 m above the assumed bankfull depth) channel reaches. The calculated competence of the 20-year flow was up to twofold higher than that required to entrain the largest bed particle diameters in those channel reaches, and even the bankfull flow was potentially capable of transporting the coarsest bed particles in certain of the reaches. On the other hand, some depositional channel reaches evidently led to the disconnectivity of transport of the coarsest bed material even in the case of the 20-year flood event. The longitudinal profile of the channel that

  16. AN INTERREGIONAL COMPARISON OF CHANNEL STRUCTURE, TRANSIENT STORAGE AND NUTRIENT UPTAKE IN STREAMS DRAINING MANAGED AND OLD GROWTH WATERSHEDS

    EPA Science Inventory

    We compared stream channel structure (width, depth, substrate composition) and riparian canopy with transient storage and nutrient uptake in 32 streams draining old-growth and managed watersheds in the Appalachian Mountains (North Carolina), Ouachita Mountains (Arkansas), Cascade...

  17. Predicting stream channel erosion in the lacustrine core of the upper Nemadji River, Minnesota (USA) using stream geomorphology metrics

    NASA Astrophysics Data System (ADS)

    Magner, Joseph A.; Brooks, Kenneth N.

    2008-06-01

    The USA Clean Water Act requires the development of a total maximum daily load (TMDL) when Minnesota’s water quality standard for turbidity is exceeded; however, regions underlain with fine-grained lacustrine deposits yield large natural background loads of suspended inorganic sediment. A review of hydrogeologic pathways was conducted along with the statistical analysis of geomorphic metrics, collected at 15 sites with varying drainage areas in the upper Nemadji River basin, northeastern Minnesota. Regression analysis indicated a strong linkage between bankfull cross-sectional area and drainage area. Dimensionless geomorphic metric ratios were developed to predict channel evolution potential and associated channel erosion risk. Sites located in drainage areas less than 2 km2 had low erosion risk and showed a correlation between channel slope and relative roughness ( D 84/mean bankfull channel depth, 88%). A principal components analysis explained over 98% of the variance between sites and indicated five important channel shape metrics to predict channel erosion: bankfull width, bankfull depth, maximum depth, cross-sectional area, and valley beltwidth. Mass wasting of cohesive stream channel sediment was influenced by groundwater discharge and produced turbid waters in the upper Nemadji River.

  18. Sources and interpretation of channel complexity in forested subalpine streams of the Southern Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Livers, Bridget; Wohl, Ellen

    2016-05-01

    We evaluate correlations between stream geomorphic complexity and characteristics of the adjacent riparian forest, valley geometry, and land use history in forested subalpine streams of the Colorado Front Range. Measures of geomorphic complexity focus on cross-sectional, planform, and instream wood piece and logjam variables. We categorize adjacent riparian forests as old-growth unmanaged forest (OU), younger unmanaged forest (YU), and younger managed forest (YM), and valley geometry as laterally confined, partly confined, or unconfined. Significant differences in geomorphic stream complexity between OU, YU, and YM result primarily from differences in wood pieces and logjams, and these differences correlate strongly with pool volume and organic matter storage. Significant differences in planform and cross-sectional complexity correlate more strongly with valley geometry, but do not explain as much of the observed variability in complexity between streams as do the wood variables. Unconfined OU streams have the largest wood loads and the greatest complexity, whereas legacy effects of logging, tie-drives, and channel simplification create lower complexity in YM streams, even relative to YU streams flowing through similarly aged forest. We find that management history of riparian forests exerts the strongest control on reduced functional stream channel complexity, regardless of riparian forest stand age.

  19. Geomorphic and vegetative recovery processes along modified stream channels of West Tennessee

    USGS Publications Warehouse

    Simon, Andrew; Hupp, C.R. Tennessee

    1992-01-01

    Hundreds of miles of streams in West Tennessee have been channelized or otherwise modt@ed since the turn of century. After all or parts of a stream are straightened, dredged, or cleared, systematic hydrologic, geomorphic, and ecologic processes collectively begin to reduce energy conditions towards the premodified state. One hundred and five sites along 15 streams were studied in the Obion, Forked Deer, Hatchie, and Wolf River basins. All studied streams, except the Hatchie River, have had major channel modi@cation along all or parts of their courses. Bank material shear-strength properties were determined through drained borehole-shear testing (168 tests) and used to interpret present critical bank conditions and factors of safety, and to estimate future channel-bank stability. Mean values of cohesive strength and angle of internal friction were 1.26 pounds per square inch and 30.1 degrees, respectively. Dendrogeomorphic analyses were made using botanical evidence of channel-bank failures to determine rates of channel widening; buried riparian stems were analyzed to determine rates of bank accretion. Channel bed-level changes through time and space were represented by a power equation. Plant ecological analyses were ma& to infer relative bank stability, to identify indicator species of the stage of bank recovery, and to determine patterns of vegetation development through the course of channel evolution. Quantitative data on morphologic changes were used with previously developed six-stage models of channel evolution and bank-slope development to estimate trends of geomorphic and ecologic processes and forms through time. Immediately after channel modr@cations, a 10- to 1%yearperiod of channel-bed degradation ensues at and upstream from the most recent modifications (area of maximum disturbance). Channel-bed lowering by &gradation was as much as 20 feet along some stream reaches. Downstream from the area of maximum disturbance, the bed was aggraded by the

  20. Stream sediment sources in midwest agricultural basins with land retirement along channel

    USGS Publications Warehouse

    Williamson, Tanja N.; Christensen, Victoria G.; Richardson, William B.; Frey, Jeffrey W.; Gellis, Allen C.; Kieta, K. A.; Fitzpatrick, Faith A.

    2014-01-01

    Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses were that sediment from cropland, retired land, stream banks, and roads would be discernible using isotopic and elemental concentrations and that source contributions would vary with land retirement distribution along tributaries of West Fork Beaver Creek in Minnesota. Channel-bed and suspended sediment were sampled at nine locations and compared with local source samples by using linear discriminant analysis and a four-source mixing model that evaluated seven tracers: In, P, total C, Be, Tl, Th, and Ti. The proportion of sediment sources differed significantly between suspended and channel-bed sediment. Retired land contributed to channel-bed sediment but was not discernible as a source of suspended sediment, suggesting that retired-land material was not mobilized during high-flow conditions. Stream banks were a large contributor to suspended sediment; however, the percentage of stream-bank sediment in the channel bed was lower in basins with more continuous retired land along the riparian corridor. Cropland sediments had the highest P concentrations; basins with the highest cropland-sediment contributions also had the highest P concentrations. Along stream reaches with retired land, there was a lower proportion of cropland material in suspended sediment relative to sites that had almost no land retirement, indicating less movement of nutrients and sediment from cropland to the channel as a result of land retirement.

  1. Stream Sediment Sources in Midwest Agricultural Basins with Land Retirement along Channel.

    PubMed

    Williamson, T N; Christensen, V G; Richardson, W B; Frey, J W; Gellis, A C; Kieta, K A; Fitzpatrick, F A

    2014-09-01

    Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our hypotheses were that sediment from cropland, retired land, stream banks, and roads would be discernible using isotopic and elemental concentrations and that source contributions would vary with land retirement distribution along tributaries of West Fork Beaver Creek in Minnesota. Channel-bed and suspended sediment were sampled at nine locations and compared with local source samples by using linear discriminant analysis and a four-source mixing model that evaluated seven tracers: In, P, total C, Be, Tl, Th, and Ti. The proportion of sediment sources differed significantly between suspended and channel-bed sediment. Retired land contributed to channel-bed sediment but was not discernible as a source of suspended sediment, suggesting that retired-land material was not mobilized during high-flow conditions. Stream banks were a large contributor to suspended sediment; however, the percentage of stream-bank sediment in the channel bed was lower in basins with more continuous retired land along the riparian corridor. Cropland sediments had the highest P concentrations; basins with the highest cropland-sediment contributions also had the highest P concentrations. Along stream reaches with retired land, there was a lower proportion of cropland material in suspended sediment relative to sites that had almost no land retirement, indicating less movement of nutrients and sediment from cropland to the channel as a result of land retirement. PMID:25603248

  2. Recent (circa 1998 to 2011) channel-migration rates of selected streams in Indiana

    USGS Publications Warehouse

    Robinson, Bret A.

    2013-01-01

    An investigation was completed to document recent (circa 1998 to 2011) channel-migration rates at 970 meander bends along 38 of the largest streams in Indiana. Data collection was completed by using the Google Earth™ platform and, for each selected site, identifying two images with capture dates separated by multiple years. Within each image, the position of the meander-bend cutbank was measured relative to a fixed local landscape feature visible in both images, and an average channel-migration rate was calculated at the point of maximum cutbank displacement. From these data it was determined that 65 percent of the measured sites have recently been migrating at a rate less than 1 ft/yr, 75 percent of the sites have been migrating at a rate less than 10 ft/yr, and while some sites are migrating in excess of 20 ft/yr, these occurrences are rare. In addition, it is shown that recent channel-migration activity is not evenly distributed across Indiana. For the stream reaches studied, far northern and much of far southern Indiana are drained by streams that recently have been relatively stationary. At the same time, this study shows that most of the largest streams in west-central Indiana and many of the largest streams in east-central Indiana have shown significant channel-migration activity during the recent past. It is anticipated that these results will support several fluvial-erosion-hazard mitigation activities currently being undertaken in Indiana.

  3. Relationships among rotational and conventional grazing systems, stream channels, and macroinvertebrates

    USGS Publications Warehouse

    Raymond, K.L.; Vondracek, B.

    2011-01-01

    Cattle grazing in riparian areas can reduce water quality, alter stream channel characteristics, and alter fish and macroinvertebrate assemblage structure. The U.S. Department of Agriculture, Natural Resources Conservation Services has recommended Rotational Grazing (RG) as an alternative management method on livestock and dairy operations to protect riparian areas and water quality. We evaluated 13 stream channel characteristics, benthic macroinvertebrate larvae (BML), and chironomid pupal exuviae (CPE) from 18 sites in the Upper Midwest of the United States in relation to RG and conventional grazing (CG). A Biotic Composite Score comprised of several macroinvertebrate metrics was developed for both the BML assemblage and the CPE assemblage. Multi-Response Permutation Procedures (MRPP) indicated a significant difference in stream channel characteristics between RG and CG. Nonmetric Multidimensional Scaling indicated that RG sites were associated with more stable stream banks, higher quality aquatic habitat, lower soil compaction, and larger particles in the streambed. However, neither MRPP nor Mann-Whitney U tests demonstrated a difference in Biotic Composite Scores for BML or CPE along RG and CG sites. The BML and CPE metrics were significantly correlated, indicating that they were likely responding to similar variables among the study sites. Although stream channel characteristics appeared to respond to grazing management, BML and CPE may have responded to land use throughout the watershed, as well as local land use. ?? 2011 Springer Science+Business Media B.V. (outside the USA).

  4. Analysis of temperature profiles for investigating stream losses beneath ephemeral channels

    USGS Publications Warehouse

    Constantz, J.; Stewart, A.E.; Niswonger, R.; Sarma, L.

    2002-01-01

    Continuous estimates of streamflow are challenging in ephemeral channels. The extremely transient nature of ephemeral streamflows results in shifting channel geometry and degradation in the calibration of streamflow stations. Earlier work suggests that analysis of streambed temperature profiles is a promising technique for estimating streamflow patterns in ephemeral channels. The present work provides a detailed examination of the basis for using heat as a tracer of stream/groundwater exchanges, followed by a description of an appropriate heat and water transport simulation code for ephemeral channels, as well as discussion of several types of temperature analysis techniques to determine streambed percolation rates. Temperature-based percolation rates for three ephemeral stream sites are compared with available surface water estimates of channel loss for these sites. These results are combined with published results to develop conclusions regarding the accuracy of using vertical temperature profiles in estimating channel losses. Comparisons of temperature-based streambed percolation rates with surface water-based channel losses indicate that percolation rates represented 30% to 50% of the total channel loss. The difference is reasonable since channel losses include both vertical and nonvertical component of channel loss as well as potential evapotranspiration losses. The most significant advantage of the use of sediment-temperature profiles is their robust and continuous nature, leading to a long-term record of the timing and duration of channel losses and continuous estimates of streambed percolation. The primary disadvantage is that temperature profiles represent the continuous percolation rate at a single point in an ephemeral channel rather than an average seepage loss from the entire channel.

  5. A cost-effective laser scanning method for mapping stream channel geometry and roughness

    NASA Astrophysics Data System (ADS)

    Lam, Norris; Nathanson, Marcus; Lundgren, Niclas; Rehnström, Robin; Lyon, Steve

    2015-04-01

    In this pilot project, we combine an Arduino Uno and SICK LMS111 outdoor laser ranging camera to acquire high resolution topographic area scans for a stream channel. The microprocessor and imaging system was installed in a custom gondola and suspended from a wire cable system. To demonstrate the systems capabilities for capturing stream channel topography, a small stream (< 2m wide) in the Krycklan Catchment Study was temporarily diverted and scanned. Area scans along the stream channel resulted in a point spacing of 4mm and a point cloud density of 5600 points/m2 for the 5m by 2m area. A grain size distribution of the streambed material was extracted from the point cloud using a moving window, local maxima search algorithm. The median, 84th and 90th percentiles (common metrics to describe channel roughness) of this distribution were found to be within the range of measured values while the largest modelled element was approximately 35% smaller than its measured counterpart. The laser scanning system captured grain sizes between 30mm and 255mm (coarse gravel/pebbles and boulders based on the Wentworth (1922) scale). This demonstrates that our system was capable of resolving both large-scale geometry (e.g. bed slope and stream channel width) and small-scale channel roughness elements (e.g. coarse gravel/pebbles and boulders) for the study area. We further show that the point cloud resolution is suitable for estimating ecohydraulic parameters such as Manning's n and hydraulic radius. Although more work is needed to fine-tune our system's design, these preliminary results are encouraging, specifically for those with a limited operational budget.

  6. Connecting Streams to Watersheds Through Stream-Groundwater Exchange as Determined from the Channel

    NASA Astrophysics Data System (ADS)

    Gooseff, M. N.; Taptich, M. N.; Wlostowski, A. N.; Gerecht, K.; Payn, R. A.; Ward, A. S.; Bowden, W. B.; Fitzgerald, M.; McGlynn, B. L.; Singha, K.; Wollheim, W. M.

    2012-12-01

    The recent Rapanos decision of the U.S. Supreme Court initiated the notion of 'significant nexus ' (a critical connection between water bodies) to guide determination of covered waters by the Clean Water Act. Significant nexus determination provides an opportunity for hydrologists to inform the spatial and temporal magnitude and direction of connections between surface waters and groundwaters of watersheds. Hydrologists and ecologists have long known that these connections are critical to maintaining streamflow and the biological, chemical, and physical integrity of streams, which is a goal of the Clean Water Act. In this presentation we will discuss an approach to characterize and quantify the strength and the spatial and temporal distributions of connections between streams and watersheds. We will illustrate the application of this novel approach using results from stream tracer experiments and geophysical analyses from several headwater catchments. Our results provide a way forward to informing where and when significant nexus occurs, and therefore where and when the jurisdiction of Clean Water Act applies.

  7. SIMULATING SUB-DECADAL CHANNEL MORPHOLOGIC CHANGE IN EPHEMERAL STREAM NETWORKS

    EPA Science Inventory

    A distributed watershed model was modified to simulate cumulative channel morphologic
    change from multiple runoff events in ephemeral stream networks. The model incorporates the general design of the event-based Kinematic Runoff and" Erosion Model (KINEROS), which describes t...

  8. Do post-mining constructed channels replace functional characteristics of headwater streams?

    EPA Science Inventory

    Mountaintop mining and valley fill (MTMVF) is a method of coal mining common in eastern Kentucky and southern West Virginia. Over 1200 miles of stream channel have been buried by MTMVF. Permits for surface coal mining have recognized constructed drainage ditches associated with ...

  9. Problems with indirect determinations of peak streamflows in steep, desert stream channels

    USGS Publications Warehouse

    Glancy, Patrick A.; Williams, Rhea P.

    1994-01-01

    Many peak streamflow values used in flood analyses for desert areas are derived using the Manning equation. Data used in the equation are collected after the flow has subsided, and peak flow is thereby determined indirectly. Most measurement problems and associated errors in peak-flow determinations result from (1) channel erosion or deposition that cannot be discerned or properly evaluated after the fact, (2) unsteady and non-uniform flow that rapidly changes in magnitude, and (3) appreciable sediment transport that has unknown effects on energy dissipation. High calculated velocities and Froude numbers are unacceptable to some investigators. Measurement results could be improved by recording flows with a video camera, installing a recording stream gage and recording rain gages, measuring channel scour with buried chains, analyzing measured data by multiple techniques, and supplementing indirect measurements with direct measurements of stream velocities in similar ephemeral streams.

  10. Biotic drivers of anastomosing channel pattern in headwater streams of the Colorado Rocky Mountains

    NASA Astrophysics Data System (ADS)

    Wohl, E. E.

    2010-12-01

    Most of the headwater rivers in the Colorado Rocky Mountains, USA occur as single channels in steep, narrow valleys. Where variations in bedrock erodibility create segments of wider, lower gradient valleys, however, anastomosing channels can occur if one of two biotic drivers is present. Where a disturbance such as a forest fire or windstorm allows pioneer woody species to colonize valley bottoms, beavers can establish colonies. Beavers build dams that enhance overbank flooding and raise the local water table, limiting the return of conifers and promoting aspen-willow (Populus-Salix) forests that provide food for the beavers. Beavers facilitate the formation of multiple channels by digging small canal-like features across the floodplain and by damming the main channel and promoting channel avulsion. In old-growth conifer forests, channel-spanning logjams can enhance overbank flows that facilitate the development of multiple (sub)parallel channels that extend for 50-300 m downstream. Enhanced overbank flows and multiple channels increase the retention of instream wood, creating a self-enhancing feedback of more jams. At least two thresholds must be crossed for anastomosing driven by logjams to develop; a valley morphology threshold and a wood load threshold. Anastomosing channels are present where stream gradient < 4% and the ratio of (channel width/valley-bottom width) < 0.2; only single channels flow through old-growth forests in valley segments that are steeper and narrower. The average wood piece diameter in old-growth anastomosing channel segments > 20 cm, whereas average piece diameter in forests that have not been disturbed in a century is 10-20 cm; channels in these younger forests do not exhibit anastomosing planforms. Wood load in old-growth anastomosing channels averages 200 m3/ha; old-growth and younger forest single channels average < 100 m3/ha.

  11. Modeling channel morphodynamic response to variations in large wood: Implications for stream rehabilitation in degraded watersheds

    NASA Astrophysics Data System (ADS)

    Davidson, Sarah L.; Eaton, Brett C.

    2013-11-01

    Anthropogenic modification of forests has often decoupled streams from riparian ecosystems and altered natural wood recruitment processes. Extensive research has shown that large wood significantly impacts channel dynamics, especially in small and intermediate sized forested streams where wood pieces are similar in length to channel width, and many stream rehabilitation efforts now involve the addition of large wood to streams. The primary objective of this research is to investigate the relation between large wood and reach scale channel morphology and hydraulics using a physical model, in order to better inform stream rehabilitation programs and future modeling efforts. Four experiments, each comprising numerous five hour runs, were conducted using a Froude-scaled stream table with wood loads scaled to 0 m3/m2, 0.011 m3/m2, 0.016 m3/m2, and 0.022 m3/m2. The addition of large wood significantly decreased the reach-averaged velocity in all experiments, and was associated with decreased sediment transport and increased sediment storage in the reach. Increases in bed and water surface slope compensated for the loss of energy available to transport sediment, and enabled the system to reach a new steady state within the equivalent of 6 to 9 years. Adding wood increased pool frequency, as well as the variability in cross-sectional depth, while causing the reach to undergo a transition from a plane-bed to a riffle-pool morphology. Retention of fine sediment increased the availability of fish spawning substrate, while increased water stage improved connectivity between the channel and the floodplain. The changes in habitat complexity were generally related to the wood load added to the reach, but were also dependent on the orientation and arrangement of the pieces. These results demonstrate that wood may exert a primary control on channel morphodynamics and the availability of aquatic habitat in intermediate sized streams, and suggest that the benefits from stream

  12. Influence of diurnal cycles on metal concentrations and loads in streams draining abandoned mine lands: an example from High Ore Creek, Montana

    NASA Astrophysics Data System (ADS)

    Gammons, Christopher H.; Milodragovich, Lica; Belanger-Woods, Jodi

    2007-11-01

    Diurnal water samples were collected simultaneously at four locations along High Ore Creek (Montana, USA), a small stream with near-neutral pH that contains elevated concentrations of Zn, Mn, Cd, and As from abandoned mines near its headwaters. During the same time period, two sets of synoptic samples were collected by workers moving in opposite directions along the stream. Large diurnal fluctuations in Zn concentration were found at three of the 24-h monitoring stations, but not at the outlet to a settling pond. Because the concentrations of Zn were dropping at most locations in the creek during the day (in response to the daily cycle of day-time attenuation and night-time release), the synoptic sampler who moved upstream obtained a data set that led to the conclusion that Zn load increased with distance downstream. The sampler who moved in a downstream direction obtained the opposite results. Thus, failure to take short-term diurnal cycling into account can lead to incorrect conclusions regarding spatial or temporal trends in water quality within a watershed.

  13. Guidelines for Surveying Bankfull Channel Geometry and Developing Regional Hydraulic-Geometry Relations for Streams of New York State

    USGS Publications Warehouse

    Powell, Rocky O.; Miller, Sarah J.; Westergard, Britt E.; Mulvihill, Christiane I.; Baldigo, Barry P.; Gallagher, Anne S.; Starr, Richard R.

    2004-01-01

    Many disturbed streams within New York State are being restored in an effort to provide bank and bed stability and thereby decrease sedimentation and erosion. Efforts to identify and provide accurate indicators for stable-channel characteristics for ungaged streams have been hampered by the lack of regional equations or relations that relate drainage area to bankfull discharge and to channel depth, width, and cross-sectional area (bankfull hydraulic-geometry relations). Regional equations are needed to confirm bankfull hydraulic-geometry, assess stream stability, evaluate restoration needs, and verify restoration design for ungaged streams that lack stage-to-discharge ratings or historic peak-flow records. This report presents guidelines for surveying bankfull channel geometry at USGS stream gages and developing regional hydraulic-geometry relations (equations) for wadeable streams in New York. It summarizes methods to (1) compile and assess existing hydrologic, geometric, photographic, and topographic data, (2) conduct stream-reconnaissance inspections, (3) identify channel-bankfull characteristics, (4) conduct longitudinal and cross-section surveys, (5) measure stream discharge, (6) develop and refine bankfull hydraulic-geometry equations, and (7) analyze and assure data completeness and quality. The techniques primarily address wadeable streams with either active or discontinued surface-water and crest-stage gages. The relations can be applied to ungaged or actively gaged streams that are wadeable, and may be extended to non-wadeable streams (with some limitations) if they have drainage areas comparable to those used to develop the relations.

  14. Measuring flood discharge in unstable stream channels using ground-penetrating radar

    USGS Publications Warehouse

    Spicer, K.R.; Costa, J.E.; Placzek, G.

    1997-01-01

    Field experiments were conducted to test the ability of ground-penetrating radar (GPR) to measure stream-channel cross sections at high flows without the necessity of placing instruments in the water. Experiments were conducted at four U.S. Geological Survey gaging stations in southwest Washington State. With the GPR antenna suspended above the water surface from a bridge or cableway, traverses were made across stream channels to collect radar profile plots of the streambed. Subsequent measurements of water depth were made using conventional depth-measuring equipment (weight and tape) and were used to calculate radar signal velocities. Other streamflow-parameter data were collected to examine their relation to radar signal velocity and to claritv of streambed definition. These initial tests indicate that GPR is capable of producing a reasonably accurate (??20%) stream-channel profile and discharge far more quickly than conventional stream-gaging procedures, while avoiding the problems and hazards associated with placing instruments in the water.

  15. Impact of riverine wetlands construction and operation on stream channel stability: Conceptual framework for geomorphic assessment

    NASA Astrophysics Data System (ADS)

    Rhoads, Bruce L.; Miller, Michael V.

    1990-11-01

    Wetland conservation is a critical environmental management issue. An emerging approach to this issue involves the construction of wetland environments. Because our understanding of wetlands function is incomplete and such projects must be monitored closely because they may have unanticipated impacts on ecological, hydrological, and geomorphological systems. Assessment of project-related impacts on stream channel stability is an important component of riverine wetlands construction and operation because enhanced erosion or deposition associated with unstable rivers can lead to loss of property, reductions in channel capacity, and degradation of water quality, aquatic habitat, and riparian aesthetics. The water/sediment budget concept provides a scientific framework for evaluating the impact of riverine wetlands construction and operation on stream channel stability. This concept is based on the principle of conservation of mass, i.e., the total amount of water and sediment moving through a specific reach of river must be conserved. Long-term measurements of channel sediment storage and other water/sediment budget components provide the basis for distinguishing between project-related impacts and those resulting from other causes. Changes in channel sediment storage that occur as a result of changes in internal inputs of water or sediment signal a project-related impact, whereas those associated with changes in upstream or tributary inputs denote a change in environmental conditions elsewhere in the watershed. A geomorphic assessment program based on the water/sediment budget concept has been implemented at the site of the Des Plaines River Wetlands Demonstration Projection near Chicago, Illinois, USA. Channel sediment storage changed little during the initial construction phase, suggesting that thus far the project has not affected stream channel stability.

  16. Verification of roughness coefficients for selected natural and constructed stream channels in Arizona

    USGS Publications Warehouse

    Phillips, Jeff V.; Ingersoll, Todd L.

    1998-01-01

    Physical and hydraulic characteristics are presented for 14 river and canal reaches in Arizona for which 37 roughness coefficients have been determined. The verified roughness coefficients which ranged from 0.017 to 0.067, were computed from discharges, channel geometry, and water-surface profiles measured at each of the sites. The information given for each stream segment includes bed and bank descriptions, data tables showing hydraulic components, a plan view, cross-section plots, and color photographs that can be used as a comparison aid in determining roughness coefficients for similarly channeled streams. Relations derived from the data presented relate Manning's roughness coefficient (n) to various hydraulic components. For gravel-bed streams, verified roughness coefficients are related to median grain size of the bed material and hydraulic radius resulting in an equation that can be used to transfer results to similar dry-land channels. The equation developed for base values of n for gravel-bed channels in Arizona is significantly different from similarly derived equations for other regions of the United States and the world.

  17. Coupled Radon and Water Temperature Measurements to Characterize the Effects of Altered Stream Channel Planform

    NASA Astrophysics Data System (ADS)

    Amerson, B. E.; Poole, G. C.; O'Daniel, S. J.

    2013-12-01

    In summer 2011, a 2.6 km reach of Meacham Creek, Oregon, USA, was altered from a straight, steep wall-based channel to more a sinuous, low-gradient channel. Key objectives of this restoration project were to increase the rate and magnitude of hyporheic exchange. The overarching goal was to initiate increased buffering and lagging of water temperature in the subsurface to mitigate warm surface water temperature in Meacham Creek, an important spawning and rearing stream for depressed populations of Chinook salmon and summer steelhead. To evaluate progress toward project goals and objectives, stream temperature and groundwater temperature in 22 wells have been measured hourly at the restoration site since March 2011. In addition, the radioactive isotope 222Rn was measured in each well and in the surface water on two occasions. The relative residence time of down welling stream water measured in the wells can be determined by ranked amplitude depression and lagged phase of annual temperature signals in the wells relative to that of the open channel flow. Residence times predicted by annual temperature signal dynamics are corroborated by 222Rn concentrations in each well. The data collected to date provide a foundation for developing a groundwater thermal model to predict the effects of channel reconfiguration on ground-surface water exchange and associated temperature effects at the reach scale.

  18. Channel morphology and sediment origin in streams draining the Georgia Piedmont

    NASA Astrophysics Data System (ADS)

    Schoonover, Jon E.; Lockaby, B. Graeme; Shaw, Joey N.

    2007-08-01

    SummaryUrbanization is common across much of the US However, the Southeast, including the Georgia Piedmont, is developing much faster than other regions ( USDA, NRCS, 2004). Consequently, water resources in the Middle Chattahoochee Watershed of western Georgia are threatened by increased sedimentation from extensive urban development as well as from other land covers such as livestock grazing and silviculture. A 2-yr study was developed to assess sediment transport and origin across 16 watersheds draining urban, developing, pastoral, managed forest and unmanaged forest landscapes. Total suspended solids (TSS) and total dissolved solids (TDS) yields and sediment rating curves were measured concomitantly with channel morphometry measurements in each stream. Urban streams featured the lowest baseflow concentrations, but sediment concentrations rose rapidly during stormflow in urban streams. Detailed cross-sections assessed channel stability and showed that pasture streams were the most unstable streams during stormflows. Finally, sediment source tracking was performed in a subset of intermittent streams using amorphous to crystalline ratios of iron to estimate the fraction of sediment coming from instream vs. landscape sources. Artificial stormflows were generated to mobilize bed sediment for the development of an instream sediment signature. If these ratios differed during natural events, it was inferred the differences were due to sediments mobilized from the terrestrial landscape. Results indicated that higher ratios of amorphous:crystalline Fe occurred during artificial floods (urban = 0.60 and unmanaged forest = 0.14) than natural stormflows (urban = 0.08 and unmanaged forest = 0.03) in watersheds dominated by urban and unmanaged forest land cover, suggesting that crystalline (i.e., terrestrial) sources of Fe were transported to the stream during rainfall events.

  19. Riparian Vegetation Influence on Stream Channel Dimensions: Key Driving Mechanisms and Their Timescales

    NASA Astrophysics Data System (ADS)

    McBride, M.; Hession, W.; Rizzo, D. M.; Thompson, D. M.

    2006-05-01

    Combined results from field-based investigations and flume experiments demonstrated key mechanisms driving channel widening following the reforestation of riparian zones in small streams. Riparian reforestation is a common occurrence either due to restoration efforts, intended to improve water quality, temperature regimes, and in-stream physical habitat or due to passive reforestation that is common when agricultural land uses decline. Previous studies have documented the influence of riparian vegetation on channel size, but driving mechanisms and the timescales at which they operate have not been evaluated. Field-based investigations were conducted in the Sleepers River basin in northeastern Vermont to revisit streams that were previously surveyed in the 1960s. We measured channel dimensions, large woody debris (LWD), and steam velocities in reaches with non-forested and forested riparian vegetation, in reaches currently in transition between vegetation types, and reaches with no change in riparian vegetation over the last 40 years. Flume experiments were performed with a 1:5 scale, fixed-bed model of a tributary to Sleepers River. Two types of riparian vegetation scenarios were simulated: 1) forested, with rigid, wooden dowels; and 2) non-forested, with synthetic grass carpeting. Three-dimensional velocities were measured during flume runs to determine turbulent kinetic energy (TKE) during overbank flows. Results showed that stream reaches with recently reforested vegetation have widened since the mid 1960s, but are not as wide as reaches with older riparian forests. LWD was more abundant in reaches with older riparian forests than in reaches with younger forests; however, scour around LWD did not appear to be a significant driving mechanism for channel widening. Velocity and TKE measurements from the prototype stream and the flume model indicate that TKE was significantly elevated in reforested reaches. Given that bed and bank erosion can be amplified in flows

  20. Potential risk assessment in stream sediments, soils and waters after remediation in an abandoned W>Sn mine (NE Portugal).

    PubMed

    Antunes, I M H R; Gomes, M E P; Neiva, A M R; Carvalho, P C S; Santos, A C T

    2016-11-01

    The mining complex of Murçós belongs to the Terras de Cavaleiros Geopark, located in Trás-os-Montes region, northeast Portugal. A stockwork of NW-SE-trending W>Sn quartz veins intruded Silurian metamorphic rocks and a Variscan biotite granite. The mineralized veins contain mainly quartz, cassiterite, wolframite, scheelite, arsenopyrite, pyrite, sphalerite, chalcopyrite, galena, rare pyrrhotite, stannite, native bismuth and also later bismuthinite, matildite, joseite, roosveltite, anglesite, scorodite, zavaritskite and covellite. The exploitation produced 335t of a concentrate with 70% of W and 150t of another concentrate with 70% of Sn between 1948 and 1976. The exploitation took place mainly in four open pit mines as well as underground. Three lakes were left in the area. Remediation processes of confination and control of tailings and rejected materials and phytoremediation with macrophytes from three lakes were carried out between 2005 and 2007. Stream sediments, soils and water samples were collected in 2008 and 2009, after the remediation process. Most stream sediments showed deficiency or minimum enrichment for metals. The sequential enrichment factor in stream sediments W>Bi>As>U>Cd>Sn=Ag>Cu>Sb>Pb>Be>Zn is mainly associated with the W>Sn mineralizations. Stream sediments receiving drainage of a mine dump were found to be significantly to extremely enriched with W, while stream sediments and soils were found to be contaminated with As. Two soil samples collected around mine dumps and an open pit lake were also found to be contaminated with U. The waters from the Murçós W>Sn mine area were acidic to neutral. After the remediation, the surface waters were contaminated with F(-), Al, As, Mn and Ni and must not be used for human consumption, while open pit lake waters must also not be used for agriculture because of contamination with F(-), Al, Mn and Ni. In most waters, the As occurred as As (III), which is toxic and is easily mobilized in the drainage

  1. Potential risk assessment in stream sediments, soils and waters after remediation in an abandoned W>Sn mine (NE Portugal).

    PubMed

    Antunes, I M H R; Gomes, M E P; Neiva, A M R; Carvalho, P C S; Santos, A C T

    2016-11-01

    The mining complex of Murçós belongs to the Terras de Cavaleiros Geopark, located in Trás-os-Montes region, northeast Portugal. A stockwork of NW-SE-trending W>Sn quartz veins intruded Silurian metamorphic rocks and a Variscan biotite granite. The mineralized veins contain mainly quartz, cassiterite, wolframite, scheelite, arsenopyrite, pyrite, sphalerite, chalcopyrite, galena, rare pyrrhotite, stannite, native bismuth and also later bismuthinite, matildite, joseite, roosveltite, anglesite, scorodite, zavaritskite and covellite. The exploitation produced 335t of a concentrate with 70% of W and 150t of another concentrate with 70% of Sn between 1948 and 1976. The exploitation took place mainly in four open pit mines as well as underground. Three lakes were left in the area. Remediation processes of confination and control of tailings and rejected materials and phytoremediation with macrophytes from three lakes were carried out between 2005 and 2007. Stream sediments, soils and water samples were collected in 2008 and 2009, after the remediation process. Most stream sediments showed deficiency or minimum enrichment for metals. The sequential enrichment factor in stream sediments W>Bi>As>U>Cd>Sn=Ag>Cu>Sb>Pb>Be>Zn is mainly associated with the W>Sn mineralizations. Stream sediments receiving drainage of a mine dump were found to be significantly to extremely enriched with W, while stream sediments and soils were found to be contaminated with As. Two soil samples collected around mine dumps and an open pit lake were also found to be contaminated with U. The waters from the Murçós W>Sn mine area were acidic to neutral. After the remediation, the surface waters were contaminated with F(-), Al, As, Mn and Ni and must not be used for human consumption, while open pit lake waters must also not be used for agriculture because of contamination with F(-), Al, Mn and Ni. In most waters, the As occurred as As (III), which is toxic and is easily mobilized in the drainage

  2. Regional bankfull-channel dimensions of non-urban wadeable streams in Indiana

    USGS Publications Warehouse

    Robinson, Bret A.

    2013-01-01

    During floods, damage to properties and community infrastructure may result from inundation and the processes of erosion. The damages imparted by erosion are collectively termed the fluvial erosion hazard (FEH), and the Indiana Silver Jackets Multi-agency Hazard Mitigation Taskforce is supporting a program to build tools that will assist Indiana property owners and communities with FEH-mitigation efforts. As part of that program, regional channel-dimension relations are identified for non-urban wadeable streams in Indiana. With a site-selection process that targeted the three largest physiographic regions of the state, field work was completed to measure channel-dimension and channel-geometry characteristics across Indiana. In total, 82 sites were identified for data collection; 25 in the Northern Moraine and Lake region, 31 in the Central Till Plain region, and 26 in the Southern Hills and Lowlands region. Following well established methods, for each data-collection site, effort was applied to identify bankfull stage, determine bankfull-channel dimensions, and document channel-geometry characteristics that allowed for determinations of channel classification. In this report, regional bankfull-channel dimension results are presented as a combination of plots and regression equations that identify the relations between drainage area and the bankfull-channel dimensions of width, mean depth, and cross-sectional area. This investigation found that the channel-dimension data support independent relations for each of the three physiographic regions noted above. Furthermore, these relations show that, for any given drainage area, northern Indiana channels have the smallest predicted dimensions, southern Indiana channels have the largest predicted dimensions, and central Indiana channels are intermediate in their predicted dimensions. When considering the suite of variables that influence bankfull-channel dimensions, it appears that contrasting runoff characteristics

  3. Channel and Catchment Morphology, Spatial Intermittency, and Carbon Chemistry of a Headwater Stream

    NASA Astrophysics Data System (ADS)

    O'Donnell, B.; Wondzell, S. M.; Serchan, S. P.; Haggerty, R.; Ward, A. S.; Schmadel, N. M.

    2015-12-01

    We investigated carbon dynamics in a steep, forested, headwater stream in the Cascade Mountains of western Oregon, USA. Measurements from a continuously recording pCO2 probe located near the mouth of the catchment showed that the stream was always super saturated with CO2 with respect to atmospheric concentrations, ranging from 500 ppm in mid-winter to as much as 3,500 ppm in late summer. Continuous measurements of pCO2 from a hyporheic well suggested that the hyporheic zone was a likely source of the super-saturated stream water because the hyporheic concentrations of CO2 ranged from a mid-winter low of 4,000 ppm to a late summer high of 16,000 ppm. Here, we investigate the causes for the large seasonal changes in pCO2 in the stream water. We conducted longitudinal synoptic surveys of flow and carbon chemistry over the period of baseflow recession during summer 2015. The channel is narrow and steep with occasional bedrock segments. However, debris flow deposits in the lower portions of the studied reach create wider valley floors where hyporheic exchange can capture 100% of the streamflow when discharge is very low. At the beginning of the summer when discharge was relatively high, flow was spatially continuous, but by mid-summer, stream flow became spatially discontinuous. Upwelling hyporheic water in these locations appears to be super saturated with CO2. In early summer, the amount of upwelling hyporheic water was small relative to stream discharge so that hyporheic exchange had only a modest influence on stream pCO2. Later in the summer, when discharge was much smaller relative to hyporheic exchange, we observed much greater spatial variability in CO2, which averaged 2720 ppm downstream of dry segments longer than 5 m but only averaged 980 ppm in wet segments and below shorter dry segments. Over the intervening wet segments, CO2 appears to be evaded from the stream as concentrations decreased rapidly. Also, upslope accumulated area appears to control lateral

  4. Tracing sources of organic matter in adjacent urban streams having different degrees of channel modification.

    PubMed

    Duan, Shuiwang; Amon, Rainer M W; Brinkmeyer, Robin L

    2014-07-01

    Urbanization and stream-channel modifications affect organic matter concentrations and quality in streams, by altering allochthonous organic matter input and in-stream transformation. This study uses multiple tracers (δ(13)C, δ(15)N, C/N ratio, and chlorophyll-a) to track sources of organic matter in two highly urbanized bayous in Houston (Texas, USA). Wastewater treatment plants (WWTPs) are located in headwaters of both bayous and contribute more than 75% to water flow. Low isotopic relatedness to natural end-members and enriched δ(15)N values suggest the influence of WWTPs on the composition of all organic matter fractions. The two bayous differ in degree of channel improvement resulting in different responses to hydrological conditions. During high flow conditions, the influence of terrestrial organic matter and sediment resuspension was much more pronounced in the Buffalo Bayou than in the concrete-lined White Oak Bayou. Particulate organic matter (POM) in White Oak Bayou had similar values of enriched δ(15)N in all subsegments, whereas in Buffalo Bayou, the degree of δ(15)N enrichment was less in the subsegments of the lower watershed. The difference in riparian zone contributions and interactions with sediments/soils was likely responsible for the compositional differences between the two bayous. Phytoplankton inputs were significantly higher in the bayous, especially in slow-flowing sections, relative to the reference sites, and elevated phytoplankton inputs accounted for the observed stable C isotope differences between FPOM and high molecular weight dissolved organic matter (HMW DOM). Relative to POM, HMW DOM in the bayous was similar to WWTP effluents and showed minor longitudinal variability in both streams suggesting that WWTPs contribute much of the DOM in the systems. Urbanization has a major influence on organic matter sources and quality in these urban water bodies and these changes seem further enhanced by stream channel modifications.

  5. Monitoring stream stage, channel profile, and aqueous conductivity with time domain reflectometry (TDR).

    SciTech Connect

    Brainard, James Robert; Tidwell, Vincent Carroll; Coplen, Amy K.; Ruby, Douglas Scott; Coombs, Jason R.; Wright, Jerome L.; Roberts, Jesse Daniel

    2004-11-01

    Time domain reflectometry (TDR) operates by propagating a radar frequency electromagnetic pulse down a transmission line while monitoring the reflected signal. As the electromagnetic pulse propagates along the transmission line, it is subject to impedance by the dielectric properties of the media along the transmission line (e.g., air, water, sediment), reflection at dielectric discontinuities (e.g., air-water or water-sediment interface), and attenuation by electrically conductive materials (e.g., salts, clays). Taken together, these characteristics provide a basis for integrated stream monitoring; specifically, concurrent measurement of stream stage, channel profile and aqueous conductivity. Here, we make novel application of TDR within the context of stream monitoring. Efforts toward this goal followed three critical phases. First, a means of extracting the desired stream parameters from measured TDR traces was required. Analysis was complicated by the fact that interface location and aqueous conductivity vary concurrently and multiple interfaces may be present at any time. For this reason a physically based multisection model employing the S11 scatter function and Cole-Cole parameters for dielectric dispersion and loss was developed to analyze acquired TDR traces. Second, we explored the capability of this multisection modeling approach for interpreting TDR data acquired from complex environments, such as encountered in stream monitoring. A series of laboratory tank experiments were performed in which the depth of water, depth of sediment, and conductivity were varied systematically. Comparisons between modeled and independently measured data indicate that TDR measurements can be made with an accuracy of {+-}3.4x10{sup -3} m for sensing the location of an air/water or water/sediment interface and {+-}7.4% of actual for the aqueous conductivity. Third, monitoring stations were sited on the Rio Grande and Paria rivers to evaluate performance of the TDR system

  6. Rapid estimation of recharge potential in ephemeral-stream channels using electromagnetic methods, and measurements of channel and vegetation characteristics

    USGS Publications Warehouse

    Callegary, J.B.; Leenhouts, J.M.; Paretti, N.V.; Jones, C.A.

    2007-01-01

    To classify recharge potential (RCP) in ephemeral-stream channels, a method was developed that incorporates information about channel geometry, vegetation characteristics, and bed-sediment apparent electrical conductivity (??a). Recharge potential is not independently measurable, but is instead formulated as a site-specific, qualitative parameter. We used data from 259 transects across two ephemeral-stream channels near Sierra Vista, Arizona, a location with a semiarid climate. Seven data types were collected: ??a averaged over two depth intervals (0-3 m, and 0-6 m), channel incision depth and width, diameter-at-breast-height of the largest tree, woody-plant and grass density. A two-tiered system was used to classify a transect's RCP. In the first tier, transects were categorized by estimates of near-surface-sediment hydraulic permeability as low, moderate, or high using measurements of 0-3 m-depth ??a. Each of these categories was subdivided into low, medium, or high RCP classes using the remaining six data types, thus yielding a total of nine RCP designations. Six sites in the study area were used to compare RCP and ??a with previously measured surrogates for hydraulic permeability. Borehole-averaged percent fines showed a moderate correlation with both shallow and deep ??a measurements, however, correlation of point measurements of saturated hydraulic conductivity, percent fines, and cylinder infiltrometer measurements with ??a and RCP was generally poor. The poor correlation was probably caused by the relatively large measurement volume and spatial averaging of ??a compared with the spatially-limited point measurements. Because of the comparatively large spatial extent of measurement transects and variety of data types collected, RCP estimates can give a more complete picture of the major factors affecting recharge at a site than is possible through point or borehole-averaged estimates of hydraulic permeability alone. ?? 2007 Elsevier B.V. All rights reserved.

  7. Bankfull Discharge and Channel Characteristics of Streams in New York State

    USGS Publications Warehouse

    Mulvihill, Christiane I.; Baldigo, Barry P.; Miller, Sarah J.; DeKoskie, Douglas; DuBois, Joel

    2009-01-01

    Equations that relate drainage area to bankfull discharge and channel characteristics (such as width, depth, and cross-sectional area) at gaged sites are needed to help define bankfull discharge and channel characteristics at ungaged sites and can be used in stream-restoration and protection projects, stream-channel classification, and channel assessments. These equations are intended to serve as a guide for streams in areas of similar hydrologic, climatic, and physiographic conditions. New York State contains eight hydrologic regions that were previously delineated on the basis of high-flow (flood) characteristics. This report seeks to increase understanding of the factors affecting bankfull discharge and channel characteristics to drainage-area size relations in New York State by providing an in-depth analysis of seven previously published regional bankfull-discharge and channel-characteristics curves. Stream-survey data and discharge records from 281 cross sections at 82 streamflow-gaging stations were used in regression analyses to relate drainage area to bankfull discharge and bankfull-channel width, depth, and cross-sectional area. The R2 and standard errors of estimate of each regional equation were compared to the R2 and standard errors of estimate for the statewide (pooled) model to determine if regionalizing data reduced model variability. It was found that regional models typically yield less variable results than those obtained using pooled statewide equations, which indicates statistically significant regional differences in bankfull-discharge and channel-characteristics relations. All but two of the bankfull-discharge curves are within the 95-percent confidence interval bands of the statewide model; all the models have statistically similar slopes, and only one model has a unique intercept. Regional variations in channel-characteristics models of bankfull width, depth, and cross-sectional area were more prevalent than for bankfull discharge, though

  8. Water quality, organic chemistry of sediment, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee

    USGS Publications Warehouse

    Bradfield, A.D.; Flexner, N.M.; Webster, D.A.

    1993-01-01

    An investigation of water quality, organic sediment chemistry, and biological conditions of streams near an abandoned wood-preserving plant site at Jackson, Tennessee, was conducted during December 1990. The study was designed to assess the extent of possible contamination of water and biota in the streams from creosote-related discharge originating at this Superfund site. Central Creek, adjacent to the plant, had degraded water quality and biological conditions. Water samples from the most downstream station on Central Creek contained 30 micrograms per liter of pentachlorophenol, which exceeds the State's criterion maximum concentrations of 9 micrograms per liter for fish and aquatic life. Bottom-sediment samples from stations on Central Creek contained concentrations of acenaphthene, napthalene, and phenanthrene ranging from 1,400 to 2,500 micrograms per kilogram. Chronic or acute toxicity resulted during laboratory experiments using test organisms exposed to creosote-related contaminants. Sediment elutriate samples from Central Creek caused slightly to highly toxic effects on Ceriodaphnia dubia. Pimephales promelas, and Photobacterium phosphoreum. Fish-tissue samples from this station contained concentrations of naphthalene. dibenzofuran, fluorene, and phenanthrene ranging from 1.5 to 3.9 micrograms per kilogram Blue-green algae at this station represented about 79 percent of the organisms counted, whereas diatoms accounted for only 11 percent. Benthic invertebrate and fish samples from Central Creek had low diversity and density. Sediment samples from a station on the South Fork Forked Deer River downstream from its confluence with Central Creek contained concentrations of acenaphthene, anthracene, chrysene, fluoranthene, fluorene, pyrere, and phenanthrene ranging from 2,800 to 69,000 micrograms per kilogram. Sediment elutriate samples using water as elutriate from this station contained concentrations of extractable organic compounds ranging from an estimated

  9. The impacts of ski slope development on stream channel morphology in the White River National Forest, Colorado, USA

    NASA Astrophysics Data System (ADS)

    David, Gabrielle C. L.; Bledsoe, Brian P.; Merritt, David M.; Wohl, Ellen

    2009-02-01

    The combined influence of tree-clearing, road construction, snowmaking, and machine-grading can cause increased flow and sediment loads along streams in or adjacent to commercial ski resorts. These changes to stream channels can increase bank failures, bed material size, pool scour, and, in extreme cases, channel incision. We used field data from the White River National Forest in Colorado, which includes several major ski resorts, to test the hypothesis that ski slope development causes a significant difference in bank stability, undercut banks, fine sediment, wood load, pool residual depth, and particle size ( D84) between the ski area project streams and reference streams. We further hypothesize that the changes in a stream are mitigated by the density and type of vegetation growing along the banks. A significant difference is defined as a project stream that is outside the range of variability of the reference streams. To test these hypotheses, we surveyed channel conditions, channel dimensions, and vegetation along 47 stream reaches (200-300 m in length). Twenty-four of these streams are within ski areas (project streams), either adjacent to or downstream from ski slopes. Twenty-three reference streams with very little to no development in their basins are used to define reference conditions of bank stability, bank undercutting, bank height, wood load, pool residual depth, sediment size, and vegetation structure. A combination of statistical techniques, including Principal Components Analysis and Classification and Regression Tree Analysis, was used to assess the controls on stream channel morphology and to analyze the differences between project and reference streams. Project streams that are significantly different than reference streams have a combination of a higher percentage of fine sediment, smaller pool residual depth, and higher percentage of unstable banks. The impacted project streams have bed material derived from granitic rocks and a lower density

  10. Effects of an restorated stream channel on groundwater dynamics and quality

    NASA Astrophysics Data System (ADS)

    Lehr, Christian; Lewandowski, Jörg; Lischeid, Gunnar

    2013-04-01

    The effects of the restoration of an former oxbow on the interactions of groundwater and stream water is analyzed by principal component analysis of the water table series. With this approach it is possible to quantify in a spatial discrete way the impact of processes on the ground water table (Lischeid et al. 2010). At the Freienbrink site, situated in the east of Berlin (Germany), water tables were measured during a four year period at up to 18 groundwater and 2 stream water sites along two transects across an artificial peninsula surrounded by an oxbow and the regulated stream channel. In the first two years of the monitoring period the straight, artificial stream channel was the main stream channel and the oxbow was hydrologically decoupled at the upstream end. In the second two years it was the opposite. After restoration the former shortcut is now hydrologically decoupled and the former oxbow reactivated. In a study about the first year of the monitoring period colmation of the oxbow has been identified as main hindrance for the exchange of groundwater and stream water (Lewandowski et al., 2009). Subsequently the effects of the removal of the colmation in the former oxbow during the restoration process is analyzed. The analysis of the propagation of hydrological signals in the coupled groundwater stream water system is combined with the analysis of the spatial and temporal dynamics of the dominant hydrogeochemical processes. Those are identified with a non-linear variant of the principal component analysis based on water quality data. References Lewandowski, J.; Lischeid, G. & Nützmann, G. 2009. Drivers of water level fluctuations and hydrological exchange between groundwater and surface water at the lowland River Spree (Germany): field study and statistical analyses. Hydrological Processes, 23(15), 2117-2128. doi: 10.1002/hyp.7277. Lischeid, G.; Natkhin, M.; Steidl, J.; Dietrich, O.; Dannowski, R. & Merz, C. 2010. Assessing coupling between lakes and

  11. Relative influence of different habitat factors on creek chub population structure within channelized agricultural headwater streams in central Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Creek chubs (Semotilus atromaculatus) are commonly found within channelized agricultural headwater streams within the Midwestern United States. Understanding the relationships of this headwater fish species with different habitat factors will provide information that can assist with developing resto...

  12. Channel Morphology and Hydraulics as Controls on Spatial Patterns of Invertebrate Drift in a Mountain Stream.

    NASA Astrophysics Data System (ADS)

    Cienciala, P.; Hassan, M. A.

    2015-12-01

    In this research we linked spatial variability of invertebrate drift characteristics (e.g. flux, concentration, mean body size) in a mountain stream to channel morphology and hydraulic properties such as at-a-point and depth-averaged velocity and shear velocity. The study was conducted in East Creek, a small stream in British Columbia in which reach-scale morphology transitions from cobble-dominated plane-bed to gravel-bed pool-riffle. To achieve our goal, we collected vertical profiles of invertebrate drift and time-averaged velocity in various morphological units within the study reaches. The data were analyzed using linear mixed model. Our reach-scale results suggested that, generally, the study reaches had statistically similar drift characteristics despite their contrasting morphologies. At the within-reach scale, different drift characteristics displayed different trends in relation to morphological and hydraulic properties of the channel. Longitudinally, highest drift flux occurred in riffle-pool transitions. We attributed this finding primarily to higher flow velocity because there were no statistically significant differences in drift concentration between morphological units. In the vertical dimension, highest drift flux occurred near the surface owing to a combination of higher drift concentration and higher flow velocity. A different pattern was observed for mean body size of drifting invertebrates. On average, body size was smallest in riffle-pool transitions and largest near the bed. The combination of velocity, drift concentration, and drift body size structure resulted in similar biomass flux estimates in all morphological units. In the vertical dimension, biomass flux appeared to be highest near the water surface. Generally, hydraulic variables seemed to be relatively poor predictors of drift concentration and mean body size of drifting invertebrates. Our findings reveal a complex relationship between channel morphology and hydraulics and various

  13. Channel water balance and exchange with subsurface flow along a mountain headwater stream in Montana, United States

    USGS Publications Warehouse

    Payn, R.A.; Gooseff, M.N.; McGlynn, B.L.; Bencala, K.E.; Wondzell, S.M.

    2009-01-01

    Channel water balances of contiguous reaches along streams represent a poorly understood scale of stream-subsurface interaction. We measured reach water balances along a headwater stream in Montana, United States, during summer base flow recessions. Reach water balances were estimated from series of tracer tests in 13 consecutive reaches delineated evenly along a 2.6 km valley segment. For each reach, we estimated net change in discharge, gross hydrologic loss, and gross hydrologic gain from tracer dilution and mass recovery. Four series of tracer tests were performed during relatively high, intermediate, and low base flow conditions. The relative distribution of channel water along the stream was strongly related to a transition in valley structure, with a general increase in gross losses through the recession. During tracer tests at intermediate and low flows, there were frequent substantial losses of tracer mass (>10%) that could not be explained by net loss in flow over the reach, indicating that many of the study reaches were concurrently losing and gaining water. For example, one reach with little net change in discharge exchanged nearly 20% of upstream flow with gains and losses along the reach. These substantial bidirectional exchanges suggest that some channel interactions with subsurface flow paths were not measurable by net change in flow or transient storage of recovered tracer. Understanding bidirectional channel water balances in stream reaches along valleys is critical to an accurate assessment of stream solute fate and transport and to a full assessment of exchanges between the stream channel and surrounding subsurface.

  14. Meandering stream reservoirs

    SciTech Connect

    Richardson, J.G.; Sangree, J.B.; Sneider, R.M.

    1987-12-01

    Braided stream deposits, described in a previous article in this series, and meandering stream deposits commonly are excellent reservoirs. Meandering high-sinuousity channels are found on flat alluvial plains with slopes less than 1 1/2/sup 0/ (0.026 rad). These rivers have wide ranges of discharges from low-water flow to flood stage. Two main processes are responsible for development of sand bodies. These are point-bar deposits left by channel migration, and oxbow-lake deposits left in loops of the river course abandoned when the stream cuts a new course during flooding. Extremely high floods spill over the banks and deposit sheets of very fine sand, silt, and clay onto the flood plain.

  15. Main-channel slopes of selected streams in Iowa for estimation of flood-frequency discharges

    USGS Publications Warehouse

    Eash, David A.

    2003-01-01

    This report describes a statewide study conducted to develop main-channel slope (MCS) curves for 138 selected streams in Iowa with drainage areas greater than 100 square miles. MCS values determined from the curves can be used in regression equations for estimating floodfrequency discharges. Multivariable regression equations previously developed for two of the three hydrologic regions defined for Iowa require the measurement of MCS. Main-channel slope is a difficult measurement to obtain for large streams using 1:24,000-scale topographic maps. The curves developed in this report provide a simplified method for determining MCS values for sites located along large streams in Iowa within hydrologic Regions 2 and 3. The curves were developed using MCS values quantified for 2,058 selected sites along 138 selected streams in Iowa. A geographic information system (GIS) technique and 1:24,000-scale topographic data were used to quantify MCS values for the stream sites. The sites were selected at about 5-mile intervals along the streams. River miles were quantified for each stream site using a GIS program. Data points for river-mile and MCS values were plotted and a best-fit curve was developed for each stream. An adjustment was applied to all 138 curves to compensate for differences in MCS values between manual measurements and GIS quantifications. The multivariable equations for Regions 2 and 3 were developed using manual measurements of MCS. A comparison of manual measurements and GIS quantifications of MCS indicates that manual measurements typically produce greater values of MCS compared to GIS quantifications. Median differences between manual measurements and GIS quantifications of MCS are 14.8 and 17.7 percent for Regions 2 and 3, respectively. Comparisons of percentage differences between flood-frequency discharges calculated using MCS values of manual measurements and GIS quantifications indicate that use of GIS values of MCS for Region 3 substantially

  16. Vendor Abandonment.

    ERIC Educational Resources Information Center

    Hegarty, Kevin; And Others

    1986-01-01

    Three articles address the relationship between a library and the vendor of its automated system from several points of view: library-initiated vendor abandonment, vendor-initiated abandonment, nonperforming vendor and nonfunctioning system, and changing systems. Acceptance testing and financial, personnel, and legal aspects of vendor abandonment…

  17. Machine-Learning Based Channel Quality and Stability Estimation for Stream-Based Multichannel Wireless Sensor Networks

    PubMed Central

    Rehan, Waqas; Fischer, Stefan; Rehan, Maaz

    2016-01-01

    Wireless sensor networks (WSNs) have become more and more diversified and are today able to also support high data rate applications, such as multimedia. In this case, per-packet channel handshaking/switching may result in inducing additional overheads, such as energy consumption, delays and, therefore, data loss. One of the solutions is to perform stream-based channel allocation where channel handshaking is performed once before transmitting the whole data stream. Deciding stream-based channel allocation is more critical in case of multichannel WSNs where channels of different quality/stability are available and the wish for high performance requires sensor nodes to switch to the best among the available channels. In this work, we will focus on devising mechanisms that perform channel quality/stability estimation in order to improve the accommodation of stream-based communication in multichannel wireless sensor networks. For performing channel quality assessment, we have formulated a composite metric, which we call channel rank measurement (CRM), that can demarcate channels into good, intermediate and bad quality on the basis of the standard deviation of the received signal strength indicator (RSSI) and the average of the link quality indicator (LQI) of the received packets. CRM is then used to generate a data set for training a supervised machine learning-based algorithm (which we call Normal Equation based Channel quality prediction (NEC) algorithm) in such a way that it may perform instantaneous channel rank estimation of any channel. Subsequently, two robust extensions of the NEC algorithm are proposed (which we call Normal Equation based Weighted Moving Average Channel quality prediction (NEWMAC) algorithm and Normal Equation based Aggregate Maturity Criteria with Beta Tracking based Channel weight prediction (NEAMCBTC) algorithm), that can perform channel quality estimation on the basis of both current and past values of channel rank estimation. In the end

  18. Machine-Learning Based Channel Quality and Stability Estimation for Stream-Based Multichannel Wireless Sensor Networks.

    PubMed

    Rehan, Waqas; Fischer, Stefan; Rehan, Maaz

    2016-01-01

    Wireless sensor networks (WSNs) have become more and more diversified and are today able to also support high data rate applications, such as multimedia. In this case, per-packet channel handshaking/switching may result in inducing additional overheads, such as energy consumption, delays and, therefore, data loss. One of the solutions is to perform stream-based channel allocation where channel handshaking is performed once before transmitting the whole data stream. Deciding stream-based channel allocation is more critical in case of multichannel WSNs where channels of different quality/stability are available and the wish for high performance requires sensor nodes to switch to the best among the available channels. In this work, we will focus on devising mechanisms that perform channel quality/stability estimation in order to improve the accommodation of stream-based communication in multichannel wireless sensor networks. For performing channel quality assessment, we have formulated a composite metric, which we call channel rank measurement (CRM), that can demarcate channels into good, intermediate and bad quality on the basis of the standard deviation of the received signal strength indicator (RSSI) and the average of the link quality indicator (LQI) of the received packets. CRM is then used to generate a data set for training a supervised machine learning-based algorithm (which we call Normal Equation based Channel quality prediction (NEC) algorithm) in such a way that it may perform instantaneous channel rank estimation of any channel. Subsequently, two robust extensions of the NEC algorithm are proposed (which we call Normal Equation based Weighted Moving Average Channel quality prediction (NEWMAC) algorithm and Normal Equation based Aggregate Maturity Criteria with Beta Tracking based Channel weight prediction (NEAMCBTC) algorithm), that can perform channel quality estimation on the basis of both current and past values of channel rank estimation. In the end

  19. Arroyo channel head evolution in a flash-flood-dominated discontinuous ephemeral stream system

    USGS Publications Warehouse

    DeLong, Stephen B.; Johnson, Joel P.L.; Whipple, Kelin X.

    2014-01-01

    We study whether arroyo channel head retreat in dryland discontinuous ephemeral streams is driven by surface runoff, seepage erosion, mass wasting, or some combination of these hydrogeomorphic processes. We monitored precipitation, overland flow, soil moisture, and headcut migration over several seasonal cycles at two adjacent rangeland channel heads in southern Arizona. Erosion occurred by headward retreat of vertical to overhanging faces, driven dominantly by surface runoff. No evidence exists for erosion caused by shallow-groundwater–related processes, even though similar theater-headed morphologies are sometimes attributed to seepage erosion by emerging groundwater. At our field site, vertical variation in soil shear strength influenced the persistence of the characteristic theater-head form. The dominant processes of erosion included removal of grains and soil aggregates during even very shallow (1–3 cm) overland flow events by runoff on vertical to overhanging channel headwalls, plunge-pool erosion during higher-discharge runoff events, immediate postrunoff wet mass wasting, and minor intra-event dry mass wasting on soil tension fractures developing subparallel to the headwall. Multiple stepwise linear regression indicates that the migration rate is most strongly correlated with flow duration and total precipitation and is poorly correlated with peak flow depth or time-integrated flow depth. The studied channel heads migrated upslope with a self-similar morphologic form under a wide range of hydrological conditions, and the most powerful flash floods were not always responsible for the largest changes in landscape form in this environment. 

  20. Self-adjustment of stream bed roughness and flow velocity in a steep mountain channel

    NASA Astrophysics Data System (ADS)

    Schneider, Johannes M.; Rickenmann, Dieter; Turowski, Jens M.; Kirchner, James W.

    2015-10-01

    Understanding how channel bed morphology affects flow conditions (and vice versa) is important for a wide range of fluvial processes and practical applications. We investigated interactions between bed roughness and flow velocity in a steep, glacier-fed mountain stream (Riedbach, Ct. Valais, Switzerland) with almost flume-like boundary conditions. Bed gradient increases along the 1 km study reach by roughly 1 order of magnitude (S = 3-41%), with a corresponding increase in streambed roughness, while flow discharge and width remain approximately constant due to the glacial runoff regime. Streambed roughness was characterized by semivariograms and standard deviations of point clouds derived from terrestrial laser scanning. Reach-averaged flow velocity was derived from dye tracer breakthrough curves measured by 10 fluorometers installed along the channel. Commonly used flow resistance approaches (Darcy-Weisbach equation and dimensionless hydraulic geometry) were used to relate the measured bulk velocity to bed characteristics. As a roughness measure, D84 yielded comparable results to more laborious measures derived from point clouds. Flow resistance behavior across this large range of steep slopes agreed with patterns established in previous studies for both lower-gradient and steep reaches, regardless of which roughness measures were used. We linked empirical critical shear stress approaches to the variable power equation for flow resistance to investigate the change of bed roughness with channel slope. The predicted increase in D84 with increasing channel slope was in good agreement with field observations.

  1. The jet-stream channels of gas and plasma in atmospheric-pressure plasma jets

    NASA Astrophysics Data System (ADS)

    Cho, Guangsup; Kim, Yunjung; Uhm, Han Sup

    2016-08-01

    A solution to the fluid momentum equation for incompressible steady-state flow is obtained for the streams of gas and plasma inside a jet nozzle and in the open-air space. Three pressure forces are considered in the equation. The first is the pressure force of the shear stress resulting from the flow viscosity and is balanced against the second pressure force of the gas stream that is ejected into the air. The third pressure force is due to the radial expansion of the fluid channel, reducing the velocity of the fluid to zero so that we obtain the reaching distance of the fluid after ejection from the nozzle. From the solution for the fluid channel, the regional profile and the density profile of the plasma flow are also determined. The maximum distance of the gas flow with a critical Reynolds number of R nc ≈ 2000 is calculated to be 100 times that of the nozzle diameter for Ar, Ne, and He. Because the radial expansion of the plasma is ten times larger than that of neutral gases, the length of the plasma flume is a few tens of the nozzle diameter, which is significantly shorter than the gas flow distance. In the experiments, the maximum length of the plasma plume increases and then saturates as the operation voltage increases.

  2. Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico

    USGS Publications Warehouse

    Alexander, R.B.; Smith, R.A.; Schwarz, G.E.

    2000-01-01

    An increase in the flux of nitrogen from the Mississippi river during the latter half of the twentieth century has caused eutrophication and chronic seasonal hypoxia in the shallow waters of the Louisiana shelf in the northern Gulf of Mexico. This has led to reductions in species diversity, mortality of benthic communities and stress in fishery resources. There is evidence for a predominantly anthropogenic origin of the increased nitrogen flux, but the location of the most significant sources in the Mississippi basin responsible for the delivery of nitrogen to the Gulf of Mexico have not been clearly identified, because the parameters influencing nitrogen-loss rates in rivers are not well known. Here we present an analysis of data from 374 US monitoring stations, including 123 along the six largest tributaries to the Mississippi, that shows a rapid decline in the average first-order rate of nitrogen loss with channel size-from 0.45 day-1 in small streams to 0.005 day-1 in the Mississippi river. Using stream depth as an explanatory variable, our estimates of nitrogen-loss rates agreed with values from earlier studies. We conclude that the proximity of sources to large streams and rivers is an important determinant of nitrogen delivery to the estuary in the Mississippi basin, and possibly also in other large river basins.

  3. Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico

    PubMed

    Alexander; Smith; Schwarz

    2000-02-17

    An increase in the flux of nitrogen from the Mississippi river during the latter half of the twentieth century has caused eutrophication and chronic seasonal hypoxia in the shallow waters of the Louisiana shelf in the northern Gulf of Mexico. This has led to reductions in species diversity, mortality of benthic communities and stress in fishery resources. There is evidence for a predominantly anthropogenic origin of the increased nitrogen flux, but the location of the most significant sources in the Mississippi basin responsible for the delivery of nitrogen to the Gulf of Mexico have not been clearly identified, because the parameters influencing nitrogen-loss rates in rivers are not well known. Here we present an analysis of data from 374 US monitor ing stations, including 123 along the six largest tributaries to the Mississippi, that shows a rapid decline in the average first-order rate of nitrogen loss with channel size--from 0.45 day (-1) in small streams to 0.005 day (-1) in the Mississippi river. Using stream depth as an explanatory variable, our estimates of nitrogen-loss rates agreed with values from earlier studies. We conclude that the proximity of sources to large streams and rivers is an important determinant of nitrogen delivery to the estuary in the Mississippi basin, and possibly also in other large river basins.

  4. Disentangling the responses of boreal stream assemblages to low stressor levels of diffuse pollution and altered channel morphology.

    PubMed

    Turunen, Jarno; Muotka, Timo; Vuori, Kari-Matti; Karjalainen, Satu Maaria; Rääpysjärvi, Jaana; Sutela, Tapio; Aroviita, Jukka

    2016-02-15

    Non-point diffuse pollution from land use and alteration of hydromorphology are among the most detrimental stressors to stream ecosystems. We explored the independent and interactive effects of morphological channel alteration (channelization for water transport of timber) and diffuse pollution on species richness and community structure of four organism groups in boreal streams: diatoms, macrophytes, macroinvertebrates, and fish. Furthermore, the effect of these stressors on stream condition was evaluated by Ecological Quality Ratios (EQR) from the national Water Framework Directive (WFD) assessment system. We grouped 91 study sites into four groups that were impacted by either diffuse pollution or hydromorphological alteration, by both stressors, or by neither one. Macroinvertebrate richness was reduced by diffuse pollution, whereas other biological groups were unaltered. Hydromorphological modification had no effect on taxon richness of any of the assemblages. Community structure of all groups was significantly affected by diffuse pollution but not by hydromorphology. Similarly, EQRs indicated negative response by diatoms, macroinvertebrates and fish to diffuse pollution, but not to hydromorphological alteration. Agricultural diffuse pollution thus affected species identities and abundances rather than taxonomic richness. Our results suggest that channelization of boreal streams for timber transport has not altered hydromorphological conditions sufficiently to have a strong impact on stream biota, whereas even moderate nutrient enrichment may be ecologically harmful. Controlling diffuse pollution and associated land use stressors should be prioritized over restoration of in-stream habitat structure to improve the ecological condition of boreal streams.

  5. Disentangling the responses of boreal stream assemblages to low stressor levels of diffuse pollution and altered channel morphology.

    PubMed

    Turunen, Jarno; Muotka, Timo; Vuori, Kari-Matti; Karjalainen, Satu Maaria; Rääpysjärvi, Jaana; Sutela, Tapio; Aroviita, Jukka

    2016-02-15

    Non-point diffuse pollution from land use and alteration of hydromorphology are among the most detrimental stressors to stream ecosystems. We explored the independent and interactive effects of morphological channel alteration (channelization for water transport of timber) and diffuse pollution on species richness and community structure of four organism groups in boreal streams: diatoms, macrophytes, macroinvertebrates, and fish. Furthermore, the effect of these stressors on stream condition was evaluated by Ecological Quality Ratios (EQR) from the national Water Framework Directive (WFD) assessment system. We grouped 91 study sites into four groups that were impacted by either diffuse pollution or hydromorphological alteration, by both stressors, or by neither one. Macroinvertebrate richness was reduced by diffuse pollution, whereas other biological groups were unaltered. Hydromorphological modification had no effect on taxon richness of any of the assemblages. Community structure of all groups was significantly affected by diffuse pollution but not by hydromorphology. Similarly, EQRs indicated negative response by diatoms, macroinvertebrates and fish to diffuse pollution, but not to hydromorphological alteration. Agricultural diffuse pollution thus affected species identities and abundances rather than taxonomic richness. Our results suggest that channelization of boreal streams for timber transport has not altered hydromorphological conditions sufficiently to have a strong impact on stream biota, whereas even moderate nutrient enrichment may be ecologically harmful. Controlling diffuse pollution and associated land use stressors should be prioritized over restoration of in-stream habitat structure to improve the ecological condition of boreal streams. PMID:26706766

  6. Hydric soils and the relationship to plant diversity within reclaimed stream channels in semi-arid environments

    SciTech Connect

    Schladweiler, B.K.; Rexroat, S.; Benson, S.

    1999-07-01

    Wetlands are especially important in semi-arid environments, such as the Powder River Basin of northeastern Wyoming, where water is a limiting factor for living organisms. Within this coal mining region of northeastern Wyoming, jurisdictional wetlands are mapped according to the US Army Corps of Engineers 1987 delineation procedure. Within the coal mining region of northeastern Wyoming, little or no full-scale mitigation or reconstruction attempts of jurisdictional wetland areas have been made until recently. Based on the importance of wetlands in a semi-arid environment and lack of information on existing or reconstructed areas, the specific objectives of the 1998 fieldwork were: (1) To define the pre-disturbance ecological state of hydric soils within jurisdictional sections of stream channels on two coal permit areas in northeastern Wyoming, and (2) To determine the effect that hydric soil parameters have on plant community distribution and composition within the two coal permit areas. Undisturbed sections of stream channels and disturbed sections of reconstructed or modified stream channels at the Rawhide Mine and Buckskin Mine, located north of Gillette, Wyoming, were selected for the study. Soils field and laboratory information and field vegetation cover were collected during 1998 within native stream channels and disturbed stream channels that had been reclaimed at each mine. Soils laboratory information is currently preliminary and included pH, electrical conductivity and sodium adsorption ratio. Results and statistical comparisons between soils and vegetation data will be presented.

  7. Equations for estimating bankfull channel geometry and discharge for streams in Massachusetts

    USGS Publications Warehouse

    Bent, Gardner C.; Waite, Andrew M.

    2013-01-01

    Regression equations were developed for estimating bankfull geometry—width, mean depth, cross-sectional area—and discharge for streams in Massachusetts. The equations provide water-resource and conservation managers with methods for estimating bankfull characteristics at specific stream sites in Massachusetts. This information can be used for the adminstration of the Commonwealth of Massachusetts Rivers Protection Act of 1996, which establishes a protected riverfront area extending from the mean annual high-water line corresponding to the elevation of bankfull discharge along each side of a perennial stream. Additionally, information on bankfull channel geometry and discharge are important to Federal, State, and local government agencies and private organizations involved in stream assessment and restoration projects. Regression equations are based on data from stream surveys at 33 sites (32 streamgages and 1 crest-stage gage operated by the U.S. Geological Survey) in and near Massachusetts. Drainage areas of the 33 sites ranged from 0.60 to 329 square miles (mi2). At 27 of the 33 sites, field data were collected and analyses were done to determine bankfull channel geometry and discharge as part of the present study. For 6 of the 33 sites, data on bankfull channel geometry and discharge were compiled from other studies done by the U.S. Geological Survey, Natural Resources Conservation Service of the U.S. Department of Agriculture, and the Vermont Department of Environmental Conservation. Similar techniques were used for field data collection and analysis for bankfull channel geometry and discharge at all 33 sites. Recurrence intervals of the bankfull discharge, which represent the frequency with which a stream fills its channel, averaged 1.53 years (median value 1.34 years) at the 33 sites. Simple regression equations were developed for bankfull width, mean depth, cross-sectional area, and discharge using drainage area, which is the most significant explanatory

  8. Landform assemblages and sedimentary processes along the Norwegian Channel Ice Stream

    NASA Astrophysics Data System (ADS)

    Ottesen, Dag; Stokes, Chris R.; Bøe, Reidulv; Rise, Leif; Longva, Oddvar; Thorsnes, Terje; Olesen, Odleiv; Bugge, Tom; Lepland, Aave; Hestvik, Ole B.

    2016-06-01

    Several regional and detailed bathymetric datasets together with 2D and 3D seismic data are compiled to investigate the landform assemblages and sedimentary processes along the former path of the Norwegian Channel Ice Stream (NCIS). At the broad scale, the glacial geomorphology and sedimentary architecture reveals three different zones along the ice-stream path, characterized by: (1) glacial erosion in the onset zone and inner shelf area, (2) sediment transport through the main trunk of the ice stream across the mid-shelf, and (3) a zone of deposition towards the outer continental shelf edge. Along the first 400 km of the ice stream bed (outer Oslofjord-Skagerrak-Stavanger) a major overdeepening is associated with suites of crag-and-tail features at the transition from the crystalline bedrock to the sedimentary bedrock, together with evidence of glaciotectonic thrusting in the form of hill-hole pairs. Here we interpret extensive erosion of both sedimentary rocks and Quaternary sediments. This zone is succeeded by an approximately 400 km long zone, through which most of the sediments eroded from the inner shelf were transported, rather than being deposited. We infer that sediment was transported subglacially and is likely to have been advected downstream by soft sediment deformation. The thickness of till of inferred Weichselian age generally varies from 0 and 50 m and this zone is characterized by mega-scale glacial lineations (MSGLs) which we interpret to be formed in a dynamic sedimentary system dominated by high sediment fluxes, but with some localized sediment accretion associated with lineations. Towards the shelf break, the North Sea Fan extends to the deep Norwegian Sea, and reflects massive sedimentation of glacigenic debris onto the continental slope. Numerous glacigenic debris flows accumulated and constructed a unit up to 400 m thick during the Last Glacial Maximum. The presence of these three zones (erosion, transport, deposition) is consistent with

  9. Relationship between channel morphology and foraging habitat for stream salmonids: Effects of body size

    NASA Astrophysics Data System (ADS)

    Cienciala, P.; Hassan, M. A.

    2014-12-01

    Channel morphology and dynamics strongly influence fish populations in running waters by defining habitat template for movement, spawning, incubation, and foraging. In this research we adopted a modeling approach to investigate how body size controls the relationship between salmonid fish and their foraging habitat in streams. Body size is a fundamental ecological parameter which affects resource acquisition, locomotory costs, metabolic rates, and competitive abilities. We focus on two specific questions. First, we examined how distinct types of channel morphology and associated flow fields shape specific growth potential for different body size classes of trout. Second, we modeled these fish-habitat relationships in a size-structured population in the presence of intraspecific competition. In the latter scenario, fish may not be able to occupy energetically optimal foraging habitat and the predicted specific growth potential may differ from the intrinsic habitat quality. To address the research questions, we linked a 2D hydrodynamic model with a bioenergetic foraging model for drift-feeding trout. Net energy intake, simulated for four study reaches with different channel morphology, was converted into maps of specific growth rate potential. We extended this model by including a component that enabled us to estimate territory size for fish of a given body size and account for the effects of competition on spatial distribution of fish. The predictions that emerge from our simulations highlight that fish body size is an important factor that determines the relationship between channel morphology and the quality of foraging habitat. The results also indicate that distinct types of channel morphology may give rise to different energetic conditions for different body size classes of drift-feeding salmonids.

  10. Modelling the changing interactions between riparian forests, stream channel dynamics and fish habitat in mountainous watersheds affected by wildfire (Invited)

    NASA Astrophysics Data System (ADS)

    Eaton, B. C.; Davidson, S. L.

    2013-12-01

    Stream networks in the Pacific Northwest are particularly good examples of fluvial systems that are controlled by a range of biophysical interactions. Forests adjacent to such streams reinforce the channel banks, thereby affecting the channel shape, bed material transport capacity and degree of lateral activity. They also supply wood to the stream, which interacts with the channel by storing and releasing sediment, and by altering the frequency and character of pools, bars and riffles. Where wood is small enough to be transported by the stream but large enough to span the channel at some locations, jams can form that alter the channel pattern by triggering avulsions around the jams. These biophysical interactions strongly influence the quantity and quality of the physical habitat available for certain species of fish, particularly salmonids. Furthermore, they are strongly scale dependent, and the interactions (and thus habitat) characteristic of smaller channels are quite different from those typical in larger ones. These channels are also influenced (to varying degrees, depending on their scale) by disturbances to the riparian forest such as wildfire. We have developed a stochastic model to investigate how wood, sediment transport and habitat character interact across a range of channel scales (Fig. 1). The model is based on physical representations of the wood input and movement processes, and empirical relations from a set of flume experiments relating wood size and orientation to sediment accumulation, and we use it to run Monte Carlo simulations that describe the distribution of possible channel states for channels of different scale. We also use the model to investigate the response to and recovery from (in terms of physical habitat) disturbance by wildfire.

  11. Interactions among forest age, valley and channel morphology, and log jams regulate animal production in mountain streams

    NASA Astrophysics Data System (ADS)

    Walters, D. M.; Venarsky, M. P.; Hall, R. O., Jr.; Herdrich, A.; Livers, B.; Winkelman, D.; Wohl, E.

    2014-12-01

    Forest age and local valley morphometry strongly influence the form and function of mountain streams in Colorado. Streams in valleys with old growth forest (>350 years) have extensive log jam complexes that create multi-thread channel reaches with extensive pool habitat and large depositional areas. Streams in younger unmanaged forests (e.g., 120 years old) and intensively managed forests have much fewer log jams and lower wood loads. These are single-thread streams dominated by riffles and with little depositional habitat. We hypothesized that log jam streams would retain more organic matter and have higher metabolism, leading to greater production of stream macroinvertebrates and trout. Log jam reaches should also have greater emergence of adult aquatic insects, and consequently have higher densities of riparian spiders taking advantage of these prey. Surficial organic matter was 3-fold higher in old-growth streams, and these streams had much higher ecosystem respiration. Insect production (g m2 y-1) was similar among forest types, but fish density was four times higher in old-growth streams with copious log jams. However, at the valley scale, insect production (g m-1 valley-1) and trout density (number m-1 valley-1) was 2-fold and 10-fold higher, respectively, in old growth streams. This finding is because multi-thread reaches created by log jams have much greater stream area and stream length per meter of valley than single-thread channels. The more limited response of macroinvertebrates may be related to fish predation. Trout in old growth streams had similar growth rates and higher fat content than fish in other streams in spite of occurring at higher densities and higher elevation/colder temperatures. This suggests that the positive fish effect observed in old growth streams is related to greater availability of invertebrate prey, which is consistent with our original hypothesis. Preliminary analyses suggest that spider densities do not respond strongly to

  12. The effect of inundation frequency on ground beetle communities in a channelized mountain stream

    NASA Astrophysics Data System (ADS)

    Skalski, T.; Kedzior, R.; Radecki-Pawlik, A.

    2012-04-01

    Under natural conditions, river channels and floodplains are shaped by flow and sediment regime and are one of the most dynamic ecosystems. At present, European river floodplains are among the most endangered landscapes due to human modifications to river systems, including channel regulation and floodplain urbanization, and land use changes in the catchments. Situated in a transition zone between terrestrial and aquatic environments, exposed riverine sediments (ERS) play a key role in the functioning of riverine ecosystems. This study aimed to verify whether the bare granular substrate is the only factor responsible for sustaining the biota associated with ERS or the inundation frequency also plays a role, modifying the potential of particular species to colonize these habitats. Ground beetles (Col. Carabidae) were selected as the investigated group of organisms and the study was carried out in Porębianka, a Polish Carpathian stream flowing through both unconstrained channel sections and sections with varied channelization schemes (rapid hydraulic structures, concrete revetments or rip-rap of various age). In each of the distinguished channel types, four replicates of 10 pitfall traps were established in three rows varying in distance to the mean water level (at three different benches). Almost 7000 individuals belonging to 102 species were collected on 60 plots. Forward selection of redundancy analysis revealed four factors significantly describing the variation in ground beetle species data: bank modification, potential bankfull discharge, frequency of inundation and plant height. Most of the biggest species were ordered at the positive site of first axis having the highest values of periods between floods. Total biomass of ground beetles and mean biomass of individuals differed significantly between sites of various frequency of inundation, whereas the variation in abundance and species richness of ground beetles was independent of the river dynamics. The body

  13. Elimination of edge effects in micro-thermal field-flow fractionation channel of low aspect ratio by splitting the carrier liquid flow into the main central stream and the thin stream layers at the side channel walls.

    PubMed

    Janca, Josef; Dupák, Jan

    2005-03-18

    An optimized construction of the separation channel for micro-thermal field-flow fractionation (FFF) was proposed and studied experimentally. The sample is injected in such a manner that its zone moves along the channel only in the main central stream where the flow velocity profile in the plane parallel to the main accumulation wall is practically flat. This central stream is separated from the contact with the side walls of the channel by thin flowing layers of the free carrier liquid. The retained species do not reach the thin liquid streams at the side walls where the flow rate decreases rapidly to achieve zero at the side wall according to the established 3D flow velocity profile. Such a construction of the channel allows one to reduce the aspect ratio (the ratio of the channel breadth b to its thickness w) without increasing the zone broadening. The hydrodynamic splitting of the outlet streams allows one not only to increase the concentration of the detected species but also the determination of the sign of Soret coefficient.

  14. Hydrogeomorphic adjustments of stream channels disturbed by urban runoff (Yzeron River basin, France)

    NASA Astrophysics Data System (ADS)

    Navratil, O.; Breil, P.; Schmitt, L.; Grosprêtre, L.; Albert, M. B.

    2013-04-01

    SummaryThis paper presents a field investigation on hydrogeomorphic adjustments of small streams in a 147 km2 periurban catchment, the Yzeron River catchment located in France. The rapid development of periurban areas in the world is now considered as one of the main factor impacting river systems. Urban disturbances are most of the time associated with irreversible alterations of the hydrological regime, the sediment yields, with major ecological impacts and additional socio-economical costs. Nineteen stream reaches have been considered in this study, with drainage areas ranging from 0.2 to 33.9 km2 and total impervious areas ranging from 1% to 52% of the basin surface. A regional analysis was led in order (i) to quantify the hydrogeomorphic adjustments of stream channels in this periurban context, i.e. the ratios between observed values and reference/rural values; and (ii) to identify the main anthropogenic controlling factors of these adjustments. Results show that urban river channels experience a global enlargement, with a mean bankfull discharge ratio of 1.8, bankfull width and depth ratios of 1.3 and a bankfull area ratio of 1.8. This study also outlines the global increase of hydrogeomorphic adjustments with the increase of the fraction of impervious area and the level of disturbance of the flood regime. However, local anthropogenic factors seem to be much more relevant to explain the highest adjustment ratios at several river reaches (enlargement ratio up to 55). The vicinity of a river reach with road sewers and/or the urban areas is identified to be a very important factor that affects significantly the smallest streams (drainage area less than 5 km2). On the contrary, at several reaches no significant deepening or widening was observed although roads/urban sewers and urban areas were identified in their catchment. Several hypotheses are proposed, but additional works with new data (river monitoring) would be needed to propose management and

  15. Quantifying the effects of stream channels on storm water quality in a semi-arid urban environment

    NASA Astrophysics Data System (ADS)

    Gallo, Erika L.; Lohse, Kathleen A.; Brooks, Paul D.; McIntosh, Jennifer C.; Meixner, Thomas; McLain, Jean E. T.

    2012-11-01

    SummaryStormwater drainage systems can have a large effect on urban runoff quality, but it is unclear how ephemeral urban streams alter runoff hydrochemistry. This problem is particularly relevant in semi-arid regions, where urban storm runoff is considered a renewable water resource. Here we address the question: how do stream channels alter urban runoff hydrochemistry? We collected synoptic stormwater samples during three rainfall-runoff events from nine ephemeral streams reaches (three concrete or metal, three grass, three gravel) in Tucson, Arizona. We identified patterns of temporal and spatial (longitudinal) variability in concentrations of conservative (chloride and isotopes of water) and reactive solutes (inorganic-N, soluble reactive phosphorous, sulfate-S, dissolved organic carbon (DOC) and nitrogen, and fecal indicator bacteria). Water isotopes and chloride (Cl) concentrations indicate that solute flushing and evapoconcentration alter temporal patterns in runoff hydrochemistry, but not spatial hydrochemical responses. Solute concentrations and stream channel solute sourcing and retention during runoff were significantly more variable at the grass reaches (CV = 2.3 - 144%) than at the concrete or metal (CV = 1.6 - 107%) or gravel reaches (CV = 1.9 - 60%), which functioned like flow-through systems. Stream channel soil Cl and DOC decreased following a runoff event (Cl: 12.1-7.3 μg g-1 soil; DOC: 87.7-30.1 μg g-1 soil), while soil fecal indicator bacteria counts increased (55-215 CFU g-1 soil). Finding from this study suggest that the characteristics of the ephemeral stream channel substrate control biogeochemical reactions between runoff events, which alter stream channel soil solute stores and the hydrochemistry of subsequent runoff events.

  16. Channel water balance and exchange with subsurface flow along a mountain headwater stream in Montana, United States

    USGS Publications Warehouse

    Payn, R.A.; Gooseff, M.N.; McGlynn, B.L.; Bencala, K.E.; Wondzell, S.M.

    2009-01-01

    Channel water balances of contiguous reaches along streams represent a poorly understood scale of stream-subsurface interaction. We measured reach water balances along a headwater stream in Montana, United States, during summer base flow recessions. Reach water balances were estimated from series of tracer tests in 13 consecutive reaches delineated evenly along a 2.6 km valley segment. For each reach, we estimated net change in discharge, gross hydrologic loss, and gross hydrologic gain from tracer dilution and mass recovery. Four series of tracer tests were performed during relatively high, intermediate, and low base flow conditions. The relative distribution of channel water along the stream was strongly related to a transition in valley structure, with a general increase in gross losses through the recession. During tracer tests at intermediate and low flows, there were frequent substantial losses of tracer mass (>10%) that could not be explained by net loss in flow over the reach, indicating that many of the study reaches were concurrently losing and gaining water. For example, one reach with little net change in discharge exchanged nearly 20% of upstream flow with gains and losses along the reach. These substantial bidirectional exchanges suggest that some channel interactions with subsurface flow paths were not measurable by net change in flow or transient storage of recovered tracer. Understanding bidirectional channel water balances in stream reaches along valleys is critical to an accurate assessment of stream solute fate and transport and to a full assessment of exchanges between the stream channel and surrounding subsurface. Copyright 2009 by the American Geophysical Union.

  17. Evaluating the use of drone photogrammetry for measurement of stream channel morphology and response to high flow events

    NASA Astrophysics Data System (ADS)

    Price, Katie; Ballow, William

    2015-04-01

    Traditional high-precision survey methods for stream channel measurement are labor-intensive and require wadeability or boat access to streams. These conditions limit the number of sites researchers are able to study and generally prohibit the possibility of repeat channel surveys to evaluate short-term fluctuations in channel morphology. In recent years, unmanned aerial vehicles (drones) equipped with photo and video capabilities have become widely available and affordable. Concurrently, developments in photogrammetric software offer unprecedented mapping and 3D rendering capabilities of drone-captured photography. In this study, we evaluate the potential use of drone-mounted cameras for detailed stream channel morphometric analysis. We used a relatively low-cost drone (DJI Phantom 2+ Vision) and commercially available, user friendly software (Agisoft Photscan) for photogrammetric analysis of drone-captured stream channel photography. Our test study was conducted on Proctor Creek, a highly responsive urban stream in Atlanta, Georgia, within the crystalline Piedmont region of the southeastern United States. As a baseline, we performed traditional high-precision survey methods to collect morphological measurements (e.g., bankfull and wetted width, bankfull and wetted thalweg depth) at 11 evenly-spaced transects, following USGS protocols along reaches of 20 times average channel width. We additionally used the drone to capture 200+ photos along the same reaches, concurrent with the channel survey. Using the photogrammetry software, we generated georeferenced 3D models of the stream channel, from which morphological measurements were derived from the 11 transects and compared with measurements from the traditional survey method. We additionally explored possibilities for novel morphometric characterization available from the continuous 3D surface, as an improvement on the limited number of detailed cross-sections available from standard methods. These results showed

  18. Baseline Channel Geometry and Aquatic Habitat Data for Selected Streams in the Matanuska-Susitna Valley, Alaska

    USGS Publications Warehouse

    Curran, Janet H.; Rice, William J.

    2009-01-01

    Small streams in the rapidly developing Matanuska-Susitna Valley in south-central Alaska are known to support anadromous and resident fish but little is known about their hydrologic and riparian conditions, or their sensitivity to the rapid development of the area or climate variability. To help address this need, channel geometry and aquatic habitat data were collected in 2005 as a baseline of stream conditions for selected streams. Three streams were selected as representative of various stream types, and one drainage network, the Big Lake drainage basin, was selected for a systematic assessment. Streams in the Big Lake basin were drawn in a Geographic Information System (GIS), and 55 reaches along 16 miles of Meadow Creek and its primary tributary Little Meadow Creek were identified from orthoimagery and field observations on the basis of distinctive physical and habitat parameters, most commonly gradient, substrate, and vegetation. Data-collection methods for sites at the three representative reaches and the 55 systematically studied reaches consisted of a field survey of channel and flood-plain geometry and collection of 14 habitat attributes using published protocols or slight modifications. Width/depth and entrenchment ratios along the Meadow-Little Meadow Creek corridor were large and highly variable upstream of Parks Highway and lower and more consistent downstream of Parks Highway. Channel width was strongly correlated with distance, increasing downstream in a log-linear relation. Runs formed the most common habitat type, and instream vegetation dominated the habitat cover types, which collectively covered 53 percent of the channel. Gravel suitable for spawning covered isolated areas along Meadow Creek and about 29 percent of Little Meadow Creek. Broad wetlands were common along both streams. For a comprehensive assessment of small streams in the Mat-Su Valley, critical additional data needs include hydrologic, geologic and geomorphic, and biologic data

  19. Regional Curves of Bankfull Channel Geometry for Non-Urban Streams in the Piedmont Physiographic Province, Virginia

    USGS Publications Warehouse

    Lotspeich, R. Russell

    2009-01-01

    Natural-channel design involves constructing a stream channel with the dimensions, slope, and plan-view pattern that would be expected to transport water and sediment and yet maintain habitat and aesthetics consistent with unimpaired stream segments, or reaches. Regression relations for bankfull stream characteristics based on drainage area, referred to as 'regional curves,' are used in natural stream channel design to verify field determinations of bankfull discharge and stream channel characteristics. One-variable, ordinary least-squares regressions relating bankfull discharge, bankfull cross-sectional area, bankfull width, bankfull mean depth, and bankfull slope to drainage area were developed on the basis of data collected at 17 streamflow-gaging stations in rural areas with less than 20 percent urban land cover within the basin area (non-urban areas) of the Piedmont Physiographic Province in Virginia. These regional curves can be used to estimate the bankfull discharge and bankfull channel geometry when the drainage area of a watershed is known. Data collected included bankfull cross-sectional geometry, flood-plain geometry, and longitudinal profile data. In addition, particle-size distributions of streambed material were determined, and data on basin characteristics were compiled for each reach. Field data were analyzed to determine bankfull cross-sectional area, bankfull width, bankfull mean depth, bankfull discharge, bankfull channel slope, and D50 and D84 particle sizes at each site. The bankfull geometry from the 17 sites surveyed during this study represents the average of two riffle cross sections for each site. Regional curves developed for the 17 sites had coefficient of determination (R2) values of 0.950 for bankfull cross-sectional area, 0.913 for bankfull width, 0.915 for bankfull mean depth, 0.949 for bankfull discharge, and 0.497 for bankfull channel slope. The regional curves represent conditions for streams with defined channels and bankfull

  20. Stage-discharge characteristics of a Weir in a sand-channel stream

    USGS Publications Warehouse

    Gonzalez, Don D.; Scott, C.H.; Culbertson, James K.

    1969-01-01

    A unique relation between water-surface elevation and water discharge usually does not exist for sand-channel streams. The relation is affected by changes in bed roughness and changes in bed elevation because of scour and fill. An artificial control on a sand-channel stream must control both the resistance to flow and the bed elevation in order to stabilize the relation between water-surface elevation and water discharge. The weir (control structure) in the Rio Grande conveyance channel near Bernardo, N. Mex., was designed on the basis of a model study and field data (Harris and Richardson, 1964). About 72 percent of the measurements used to define the base relation between water-surface elevation and water discharge falls within plus or minus 5 percent of the mean relation for the prototype. The stage-discharge relation is not affected by backwater for values of submergence less than 90 percent. There is no consistent relation between the ratio of measured discharge to rated discharge and submergence for values of submergence greater than 90 percent. The control does not restrict the channel capacity to less than the stated design capacity of 2,000 cubic feet per second. When the control is drowned out, or ineffective, the relation of water-surface elevation to water discharge is virtually the same as that prior to construction of the control for discharges greater than 1,500 cubic feet per second. When the control is not drowned out--that is, free-fall conditions exist--the water-surface elevation for a discharge of 2,000 cubic feet per second is greater than the minimum elevation, but is less than the maximum elevation that occurred at that discharge prior to construction. The model study was only partially successful in predicting the operating characteristics of the prototype. Some of the differences between prototype operation and model predictions may exist because the prototype was not built exactly as recommended on the basis of the model study. In general

  1. Mapping Spatial Distributions of Stream Power and Channel Change along a Gravel-Bed River in Northern Yellowstone

    NASA Astrophysics Data System (ADS)

    Lea, D. M.; Legleiter, C. J.

    2014-12-01

    Stream power represents the rate of energy expenditure along a river and can be calculated using topographic data acquired via remote sensing. This study used remotely sensed data and field measurements to quantitatively relate temporal changes in the form of Soda Butte Creek, a gravel-bed river in northeastern Yellowstone National Park, to stream power gradients along an 8 km reach. Aerial photographs from 1994-2012 and cross-section surveys were used to assess lateral channel mobility and develop a morphologic sediment budget for quantifying net sediment flux for a series of budget cells. A drainage area-to-discharge relationship and digital elevation model (DEM) developed from LiDAR data were used to obtain the discharge and slope values, respectively, needed to calculate stream power. Local and lagged relationships between mean stream power gradient at median peak discharge and volumes of erosion, deposition, and net sediment flux were quantified via spatial cross-correlation analyses. Similarly, autocorrelations of locational probabilities and sediment fluxes were used to examine spatial patterns of channel mobility and sediment transfer. Energy expended above critical stream power was calculated for each time period to relate the magnitude and duration of peak flows to the total volume of sediment eroded or deposited during each time increment. Our results indicated a lack of strong correlation between stream power gradients and sediment flux, which we attributed to the geomorphic complexity of the Soda Butte Creek watershed and the inability of our relatively simple statistical approach to link sediment dynamics expressed at a sub-budget cell scale to larger-scale driving forces such as stream power gradients. Future studies should compare the moderate spatial resolution techniques used in this study to very-high resolution data acquired from new fluvial remote sensing technologies to better understand the amount of error associated with stream power

  2. Process-Based Restoration and the Rise of the Stage Zero Channel As a Stream Restoration Goal

    NASA Astrophysics Data System (ADS)

    Pollock, M. M.

    2015-12-01

    The stage zero channel (sensu Cluer and Thorne 2013) is increasingly recognized as having intrinsic high value because of the multiple and synergistic ecosystem goods and services that such channels provide. Stage zero channels have well connected floodplains with elevated water tables, spatially variable hydrologic regimes and structurally complex aquatic and riparian habitat. As such, they provide incredibly valuable habitat for a suite of terrestrial and aquatic taxa, including several Pacific salmon species that are in decline. In this presentation, we provide an overview of the features and types of stage zero channels, where in the landscape they are likely to be found, how they evolve under natural conditions, and restoration techniques for converting less ecologically valuable channel types into stage zero channels. We compare the structure and function of stage zero channels to more traditional channel restoration targets. We conclude that new approaches to stream restoration are needed that take into account society's economic and ecological imperatives to create resilient, structurally complex and dynamic systems, and that the spatial scale of restorative actions should be expanded where possible to better recognize and integrate the interdependent nature of longitudinal, lateral and vertical linkages in stream systems.

  3. Turbulent flow in pipes and channels as cross-stream ``inverse cascades'' of vorticity

    NASA Astrophysics Data System (ADS)

    Eyink, Gregory L.

    2008-12-01

    A commonplace view of pressure-driven turbulence in pipes and channels is as "cascades" of streamwise momentum toward the viscous layer at the wall. We present in this paper an alternative picture of these flows as "inverse cascades" of spanwise vorticity in the cross-stream direction but away from the viscous sublayer. We show that there is a constant spatial flux of spanwise vorticity due to vorticity conservation and that this flux is necessary to produce pressure drop and energy dissipation. The vorticity transport is shown to be dominated by viscous diffusion at distances closer to the wall than the peak Reynolds stress, well into the classical log layer. The Perry-Chong model based on "representative" hairpin/horseshoe vortices predicts a single sign of the turbulent vorticity flux over the whole log layer, whereas the actual flux must change sign at the location of the Reynolds-stress maximum. Sign reversal may be achieved by assuming a slow power-law decay of the Townsend "eddy-intensity function" for wall-normal distances greater than the hairpin length scale. The vortex-cascade picture presented here has a close analog in the theory of quantum superfluids and superconductors, the "phase slippage" of quantized vortex lines. Most of our results should therefore apply as well to superfluid turbulence in pipes and channels. We also discuss issues about drag reduction from this perspective.

  4. Spreading of a ferrofluid core in three-stream micromixer channels

    NASA Astrophysics Data System (ADS)

    Wang, Zhaomeng; Varma, V. B.; Xia, Huan Ming; Wang, Z. P.; Ramanujan, R. V.

    2015-05-01

    Spreading of a water based ferrofluid core, cladded by a diamagnetic fluid, in three-stream micromixer channels was studied. This spreading, induced by an external magnetic field, is known as magnetofluidic spreading (MFS). MFS is useful for various novel applications where control of fluid-fluid interface is desired, such as micromixers or micro-chemical reactors. However, fundamental aspects of MFS are still unclear, and a model without correction factors is lacking. Hence, in this work, both experimental and numerical analyses were undertaken to study MFS. We show that MFS increased for higher applied magnetic fields, slower flow speed of both fluids, smaller flow rate of ferrofluid relative to cladding, and higher initial magnetic particle concentration. Spreading, mainly due to connective diffusion, was observed mostly near the channel walls. Our multi-physics model, which combines magnetic and fluidic analyses, showed, for the first time, excellent agreement between theory and experiment. These results can be useful for lab-on-a-chip devices.

  5. Spreading of a ferrofluid core in three-stream micromixer channels

    SciTech Connect

    Wang, Zhaomeng; Varma, V. B.; Ramanujan, R. V.; Xia, Huan Ming; Wang, Z. P.

    2015-05-15

    Spreading of a water based ferrofluid core, cladded by a diamagnetic fluid, in three-stream micromixer channels was studied. This spreading, induced by an external magnetic field, is known as magnetofluidic spreading (MFS). MFS is useful for various novel applications where control of fluid-fluid interface is desired, such as micromixers or micro-chemical reactors. However, fundamental aspects of MFS are still unclear, and a model without correction factors is lacking. Hence, in this work, both experimental and numerical analyses were undertaken to study MFS. We show that MFS increased for higher applied magnetic fields, slower flow speed of both fluids, smaller flow rate of ferrofluid relative to cladding, and higher initial magnetic particle concentration. Spreading, mainly due to connective diffusion, was observed mostly near the channel walls. Our multi-physics model, which combines magnetic and fluidic analyses, showed, for the first time, excellent agreement between theory and experiment. These results can be useful for lab-on-a-chip devices.

  6. Fabrication and validation of a multi-channel type microfluidic chip for electrokinetic streaming potential devices.

    PubMed

    Chun, Myung-Suk; Shim, Min Suk; Choi, Nak Won

    2006-02-01

    To elaborate on the applicability of the electrokinetic micro power generation, we designed and fabricated the silicon-glass as well as the PDMS-glass microfluidic chips with the unique features of a multi-channel. Besides miniaturizing the device, the key advantage of our microfluidic chip utilization lies in the reduction in water flow rate. Both a distributor and a collector taking the tapered duct geometry are positioned aiming the uniform distribution of water flow into all individual channels of the chip, in which several hundreds of single microchannels are assembled in parallel. A proper methodology is developed accompanying the deep reactive ion etching as well as the anodic bonding, and optimum process conditions necessary for hard and soft micromachining are presented. It has been shown experimentally and theoretically that the silicon-based microchannel leads to increasing streaming potential and higher external current compared to those of the PDMS-based one. A proper comparison between experimental results and theoretical computations allows justification of the validity of our novel devices. It is useful to recognize that a material inducing a higher magnitude of zeta potential has an advantage for obtaining higher power density under the same external resistance.

  7. The fan of influence of streams and channel feedbacks to simulated land surface water and carbon dynamics

    NASA Astrophysics Data System (ADS)

    Shen, Chaopeng; Riley, William J.; Smithgall, Kurt R.; Melack, John M.; Fang, Kuai

    2016-02-01

    Large-scale land models assume unidirectional land-to-river hydrological interactions, without considering feedbacks between channels and land. Using a tested, physically based model with explicit multiway interactions between overland, channel, wetland, and groundwater flows, we assessed how the representation and properties of channels influence simulated land surface hydrologic, biogeochemical, and ecosystem dynamics. A zone near the channels where various fluxes and states are significantly influenced by the channels, referred to as the fan of influence (FoI) of channels, has been identified. We elucidated two mechanisms inducing the model-derived FoI: the base flow mechanism, in which incised, gaining streams lower the water table and induce more base flow, and the relatively more efficient conveyance of the channel network compared to overland flow. We systematically varied drainage density and grid resolution to quantify the size of the FoI, which is found to span a large fraction of the watershed (25-50%) for hydrologic variables including depth to water table and recharge, etc. The FoI is more pronounced with low-resolution simulations but remains noticeable in hyperresolution (25 m) subbasin simulations. The FoI and the channel influence on basin-average fluxes are also similar in simulations with alternative parameter sets. We found that high-order, entrenched streams cause larger FoI. In addition, removing the simulated channels has disproportionally large influence on modeled wetland areas and inundation duration, which has implications for coupled biogeochemical or ecological modeling. Our results suggest that explicit channel representation provides important feedbacks to land surface dynamics which should be considered in meso or large-scale simulations. Since grid refinement incurs prohibitive computational cost, subgrid channel parameterization has advantages in efficiency over grid-based representations that do not distinguish between overland

  8. Early break-up of the Norwegian Channel Ice Stream during the Last Glacial Maximum

    NASA Astrophysics Data System (ADS)

    Svendsen, John Inge; Briner, Jason P.; Mangerud, Jan; Young, Nicolás E.

    2015-01-01

    We present 18 new cosmogenic 10Be exposure ages that constrain the breakup time of the Norwegian Channel Ice Stream (NCIS) and the initial retreat of the Scandinavian Ice Sheet from the Southwest coast of Norway following the Last Glacial Maximum (LGM). Seven samples from glacially transported erratics on the island Utsira, located in the path of the NCIS about 400 km up-flow from the LGM ice front position, yielded an average 10Be age of 22.0 ± 2.0 ka. The distribution of the ages is skewed with the 4 youngest all within the range 20.2-20.8 ka. We place most confidence on this cluster of ages to constrain the timing of ice sheet retreat as we suspect the 3 oldest ages have some inheritance from a previous ice free period. Three additional ages from the adjacent island Karmøy provided an average age of 20.9 ± 0.7 ka, further supporting the new timing of retreat for the NCIS. The 10Be ages from Utsira and Karmøy suggest that the ice stream broke up about 2000 years earlier than the age assignment based on 14C ages on foraminifera and molluscs from marine sediment cores. We postulate that the Scandinavian Ice Sheet flowed across the Norwegian Channel to Denmark and onto the North Sea plateau during early phases of the LGM. When the NCIS started to operate this ice supply to the North Sea was cut off and the fast flow of the NCIS also led to a lowering of the ice surface along the Norwegian Channel and thereby drawdown of the entire ice sheet. This facilitated rapid calving of the ice front in the North Sea and we reconstruct a large open bay across the entire northern North Sea by ˜20 ka based on our 10Be ages in the east and radiocarbon ages from marine cores in the west. Additional 10Be ages show that the mainland slightly east of the islands Utsira and Karmøy remained ice covered until about 16 ka, indicating almost no net ice-margin retreat for the 4000 years between 20 and 16 ka. After 16 ka the ice margin retreated quickly up-fjord.

  9. Stream channel surface water - groundwater interactions in a fire impacted watershed

    NASA Astrophysics Data System (ADS)

    Russo, T. A.; Fisher, A. T.

    2010-12-01

    We are conducting a study of surface water - groundwater interactions within the Scott Creek watershed, a 4th order catchment of 76.6 km2 in central coastal California, to assess the impacts of fire on channel and riparian conditions. Scott Creek and its tributaries are valuable spawning habitat for Coho salmon and Steelhead trout. The Scott Creek watershed is located on the western (windward) side of the Santa Cruz Mountains, where the most intense precipitation falls from November to April, and includes a mixture of protected land and areas used for agriculture, grazing, and selective timber harvesting. 37% of the watershed was burned in a fire in August 2009, and we hypothesize that this could result in enhanced delivery of fine grained hill slope sediments to stream channels for several years post fire, reducing the extent of hyporheic exchange downstream of burned areas. This could reduce the survival rates of Coho and Steelhead redds (egg nests), which are dependent on surface water - groundwater exchange for regulation of water nutrient content and temperature. We are monitoring streambed seepage rates and hydraulic conductivity, and performing repeated tracer discharge experiments at three sites on Scott Creek, two within and one upstream of the area burned in the 2009 fire. Streambed seepage rates are calculated using a time series method applied to heat as a tracer, using naturally occurring diurnal changes in stream temperature, and extended to calculations of streambed hydraulic conductivity based on measured head gradients. Hyporheic exchange parameters are assessed using tracer breakthrough data, as fit by an optimized model of one-dimensional advection, dispersion and transient storage. Variations in hydrologic characteristics (e.g., transient storage area, exchange coefficient) over time at each site are being used to assess the magnitude and timing of channel modifications independent to, and associated with, the burning of catchment hill slopes

  10. Mapping spatial patterns of stream power and channel change along a gravel-bed river in northern Yellowstone

    NASA Astrophysics Data System (ADS)

    Lea, Devin M.; Legleiter, Carl J.

    2016-01-01

    Stream power represents the rate of energy expenditure along a river and can be calculated using topographic data acquired via remote sensing or field surveys. This study sought to quantitatively relate temporal changes in the form of Soda Butte Creek, a gravel-bed river in northeastern Yellowstone National Park, to stream power gradients along an 8-km reach. Aerial photographs from 1994 to 2012 and ground-based surveys were used to develop a locational probability map and morphologic sediment budget to assess lateral channel mobility and changes in net sediment flux. A drainage area-to-discharge relationship and DEM developed from LiDAR data were used to obtain the discharge and slope values needed to calculate stream power. Local and lagged relationships between mean stream power gradient at median peak discharge and volumes of erosion, deposition, and net sediment flux were quantified via spatial cross-correlation analyses. Similarly, autocorrelations of locational probabilities and sediment fluxes were used to examine spatial patterns of sediment sources and sinks. Energy expended above critical stream power was calculated for each time period to relate the magnitude and duration of peak flows to the total volumetric change in each time increment. Collectively, we refer to these methods as the stream power gradient (SPG) framework. The results of this study were compromised by methodological limitations of the SPG framework and revealed some complications likely to arise when applying this framework to small, wandering, gravel-bed rivers. Correlations between stream power gradients and sediment flux were generally weak, highlighting the inability of relatively simple statistical approaches to link sub-budget cell-scale sediment dynamics to larger-scale driving forces such as stream power gradients. Improving the moderate spatial resolution techniques used in this study and acquiring very-high resolution data from recently developed methods in fluvial remote

  11. AN INTERREGIONAL COMPARISON OF CHANNEL STRUCTURE WITH TRANSIENT STORAGE IN STREAMS DRAINING HARVESTED AND OLD-GROWTH WATERSHEDS

    EPA Science Inventory

    We compared measures of channel structure and riparian canopy with estimates of transient storage in 32 streams draining old-growth and harvested watersheds in the Southern Appalachian Mountains of North Carolina (n=4), the Ouachita Mountains of Arkansas (n=5), the Cascade Mounta...

  12. Natural-channel-design restorations that changed geomorphology have little effect on macroinvertebrate communities in headwater streams

    USGS Publications Warehouse

    Ernst, Anne G.; Warren, Dana R.; Baldigo, Barry P.

    2012-01-01

    Stream restorations that increase geomorphic stability can improve habitat quality, which should benefit selected species and local aquatic ecosystems. This assumption is often used to define primary restoration goals; yet, biological responses to restoration are rarely monitored or evaluated methodically. Macroinvertebrate communities were inventoried at 6 study reaches within 5 Catskill Mountain streams between 2002 and 2006 to characterize their responses to natural-channel-design (NCD) restoration. Although bank stability increased significantly at most restored reaches, analyses of variation showed that NCD restorations had no significant effect on 15 of 16 macroinvertebrate community metrics. Multidimensional scaling ordination indicated that communities from all reach types within a stream were much more similar to each other within any given year than they were in the same reaches across years or within any type of reach across streams. These findings indicate that source populations and watershed-scale factors were more important to macroinvertebrate community characteristics than were changes in channel geomorphology associated with NCD restoration. Furthermore, the response of macroinvertebrates to restoration cannot always be used to infer the response of other stream biota to restoration. Thus, a broad perspective is needed to characterize and evaluate the full range of effects that restoration can have on stream ecosystems.

  13. Channel change and sediment transport in two desert streams in central Arizona, 1991-92

    USGS Publications Warehouse

    Parker, J.T.

    1995-01-01

    recurrence interval of less than 5 years. A summer flow that lasted 3 hours had a peak discharge of 173 cubic meters per second and caused some bank erosion and possibly some dissection of terraces. The magnitude of change, however, was far less than that of the winter flow. Suspended-sediment concentration on the Salt River during the winter flows was typical of those for other regulated streams in Arizona and ranged from 2 to 617 milligrams per liter at discharges from 6.7 to 343 cubic meters per second. Fine-grained sediments in the channel bottom probably were the main source of sediment transported in suspension. During periods of prolonged, steady flows, suspended-sediment concentration tended to decline, which indicated a probable depletion of sediment supply. On the Hassayampa River, suspended-sediment concentrations ranged from 12,800 to 132,000 milligrams per liter at discharges of 13 to 128 cubic meters per second. The relation of sediment concentration to discharge was poor for the entire set of samples, but a clear pattern was evident for each period of storm runoff. In two of three periods of runoff sampled, maximum suspended-sediment concentration occurred just before peak discharge and declined rapidly.

  14. Detecting the impact of bank and channel modification on invertebrate communities in Mediterranean temporary streams (Sardinia, SW Italy).

    PubMed

    Buffagni, Andrea; Tenchini, Roberta; Cazzola, Marcello; Erba, Stefania; Balestrini, Raffaella; Belfiore, Carlo; Pagnotta, Romano

    2016-09-15

    We hypothesized that reach-scale, bank and channel modification would impact benthic communities in temporary rivers of Sardinia, when pollution and water abstraction are not relevant. A range of variables were considered, which include both artificial structures/alterations and natural features observed in a stream reach. Multivariate regression trees (MRT) were used to assess the effects of the explanatory variables on invertebrate assemblages and five groups, characterized by different habitat modification and/or features, were recognized. Four node variables determined the splits in the MRT analysis: channel reinforcement, tree-related bank and channel habitats, channel modification and bank modification. Continuity of trees in the river corridor diverged among MRT groups and significant differences among groups include presence of alders, extent of channel shading and substrate diversity. Also, the percentage of in-stream organic substrates, in particular CPOM/Xylal, showed highly significant differences among groups. For practical applications, thresholds for the extent of channel reinforcement (40%) and modification (10%) and for bank alteration (≈30%) were provided, that can be used to guide the implementation of restoration measures. In moderately altered river reaches, a significant extent of tree-related habitats (≈5%) can noticeably mitigate the effects of morphological alteration on aquatic invertebrates. The outcomes highlight the importance of riparian zone management as an opportune, achievable prospect in the restoration of Mediterranean temporary streams. The impact of bank and channel modification on ecological status (sensu WFD) was investigated and the tested benthic metrics, especially those based on abundance data, showed legible differences among MRT groups. Finally, bank and channel modification appears to be a potential threat for the conservation of a few Sardo-Corsican endemic species. The introduction of management criteria that

  15. Detecting the impact of bank and channel modification on invertebrate communities in Mediterranean temporary streams (Sardinia, SW Italy).

    PubMed

    Buffagni, Andrea; Tenchini, Roberta; Cazzola, Marcello; Erba, Stefania; Balestrini, Raffaella; Belfiore, Carlo; Pagnotta, Romano

    2016-09-15

    We hypothesized that reach-scale, bank and channel modification would impact benthic communities in temporary rivers of Sardinia, when pollution and water abstraction are not relevant. A range of variables were considered, which include both artificial structures/alterations and natural features observed in a stream reach. Multivariate regression trees (MRT) were used to assess the effects of the explanatory variables on invertebrate assemblages and five groups, characterized by different habitat modification and/or features, were recognized. Four node variables determined the splits in the MRT analysis: channel reinforcement, tree-related bank and channel habitats, channel modification and bank modification. Continuity of trees in the river corridor diverged among MRT groups and significant differences among groups include presence of alders, extent of channel shading and substrate diversity. Also, the percentage of in-stream organic substrates, in particular CPOM/Xylal, showed highly significant differences among groups. For practical applications, thresholds for the extent of channel reinforcement (40%) and modification (10%) and for bank alteration (≈30%) were provided, that can be used to guide the implementation of restoration measures. In moderately altered river reaches, a significant extent of tree-related habitats (≈5%) can noticeably mitigate the effects of morphological alteration on aquatic invertebrates. The outcomes highlight the importance of riparian zone management as an opportune, achievable prospect in the restoration of Mediterranean temporary streams. The impact of bank and channel modification on ecological status (sensu WFD) was investigated and the tested benthic metrics, especially those based on abundance data, showed legible differences among MRT groups. Finally, bank and channel modification appears to be a potential threat for the conservation of a few Sardo-Corsican endemic species. The introduction of management criteria that

  16. Mapping spatial patterns of stream power and channel change along a gravel-bed river in northern Yellowstone

    NASA Astrophysics Data System (ADS)

    Lea, Devin M.

    Stream power represents the rate of energy expenditure along a river and can be calculated using topographic data acquired via remote sensing or field surveys. This study used remote sensing and GIS tools along with field data to quantitatively relate temporal changes in the form of Soda Butte Creek, a gravel-bed river in northeastern Yellowstone National Park, to stream power gradients along an 8 km reach. Aerial photographs from 1994-2012 and cross-section surveys were used to develop a locational probability map and morphologic sediment budget to assess lateral channel mobility and changes in net sediment flux. A drainage area-to-discharge relationship and digital elevation model (DEM) developed from light detection and ranging (LiDAR) data were used to obtain the discharge and slope values needed to calculate stream power. Local and lagged relationships between mean stream power gradient at median peak discharge and volumes of erosion, deposition, and net sediment flux were quantified via spatial cross-correlation analyses. Similarly, autocorrelations of locational probabilities and sediment fluxes were used to examine spatial patterns of sediment sources and sinks. Energy expended above critical stream power was calculated for each time period to relate the magnitude and duration of peak flows to the total volumetric change in each time increment. Results indicated a lack of strong correlation between stream power gradients and sediment response, highlighting the geomorphic complexity of Soda Butte Creek and the inability of relatively simple statistical approaches to link sub-budget cell-scale sediment dynamics to larger-scale driving forces such as stream power gradients. Improving the moderate spatial resolution techniques used in this study and acquiring very-high resolution data from recently developed methods in fluvial remote sensing could help improve understanding of the spatial organization of stream power, sediment transport, and channel change in

  17. Analysis of Stream Channel Geometry Temporal and Spatial Evolution after Historic Dam Removal - two French case studies

    NASA Astrophysics Data System (ADS)

    Slawson, Deborah; Manière, Louis; Marchandeau, Florent

    2014-05-01

    IRSTEA, in partnership with the French Office national de l'eau et des milieux aquatiques (ONEMA), has begun a study of channel geomorphology in small streams where dams have been removed or breached between two and 200 years ago, without any subsequent restoration of the channel in the legacy sediments. A preliminary analysis of two sites in the Morvan, Burgundy, will be presented; a dam breached at the beginning of the 20th century and another in the last decade. Using ergodic reasoning, historical and recent upstream and downstream channel geometry is being used to predict the future temporal and spatial scales of channel physical habitat restoration. With the implementation of the European Water Framework Directive (WFD), dam removal has become a more frequently used method for restoring stream ecological continuity. In France, these obstacles are ubiquitous in medium and small streams and considerably reduce lateral and longitudinal connectivity. Improvement in the hydromorphologically controlled, physical habitat, particularly flow and sediment transport regimes, is often essential to improvement in stream biology. However, dam removal may cause long-term disturbances in flow and sediment transport regimes. In the absence of channel restoration measures in addition to dam removal, these disturbances may result in long-term negative impacts on fish, macroinvertebrate, and riparian plant physical habitat. These negative impacts may include channel incision and lowering of the water table, disconnection from floodplains, increased stream power and bed scouring, and increased sediment load from headcutting and bank erosion. Over time, these negative impacts may resolve themselves. However, the time frame necessary for reestablishing adequate physical habitat is not well-known. Some studies have indicated that many decades or longer may be required, depending on a variety of factors. Under the WFD, the REstoring rivers FOR effective catchment Management (REFORM

  18. Effects of variation in streamflow and channel structure on smallmouth bass habitat in an alluvial stream

    USGS Publications Warehouse

    Jason, Remshardt W.; Fisher, W.L.

    2009-01-01

    We evaluated the effects of streamflow-related changes in channel shape and morphology on the quality, quantity, availability and spatial distribution of young-of-year and adult smallmouth bass Micropterus dolomieu habitat in an alluvial stream, the Baron Fork of the Illinois River, Oklahoma. We developed Habitat Suitability Criteria (HSC) for young-of-year and adult smallmouth bass to assess changes in available smallmouth bass habitat between years, and compare predicted smallmouth bass Weighted Usable Area (WUA) with observed WUA measured the following year. Following flood events between 1999 and 2000, including a record flood, changes in transect cross-sectional area ranged from 62.5% to 93.5% and channel mesohabitat overlap ranged from 29.5% to 67.0% in study three study reaches. Using Physical HABitat SIMulation (PHABSIM) system analysis, we found that both young-of-year and adult smallmouth bass habitat were differentially affected by intra- and inter-annual streamflow fluctuations. Maximum WUA for young-of-year and adults occurred at streamflows of 1.8 and 2.3m3 s-1, respectively, and WUA declined sharply for both groups at lower streamflows. For most microhabitat variables, habitat availability was similar between years. Habitat suitability criteria developed in 1999 corresponded well with observed fish locations in 2000 for adult smallmouth bass but not for young-of-year fish. Our findings suggest that annual variation in habitat availability affects the predictive ability of habitat models for young-of-year smallmouth bass more than for adult smallmouth bass. Furthermore, our results showed that despite the dynamic nature of the gravel-dominated, alluvial Baron Fork, HSC for smallmouth bass were consistent and transferable between years.

  19. Channel Incision and Water-Table Decline Along a Recently Formed Proglacial Stream, Mendenhall Valley, Southeastern Alaska

    USGS Publications Warehouse

    Neal, Edward G.

    2009-01-01

    Retreat of the Mendenhall Glacier, in southeastern Alaska, resulted in the formation of Mendenhall Lake, which has reduced the supply of coarse sediment to the proglacial Mendenhall River. Channel geometry surveys conducted in 1969 and 1998 over a 5.3 km reach of the Mendenhall River revealed reductions in mean bed elevations ranging from 0.4 to 1.5 meters based on cross sections replicated at 7 locations. Channel incision in the Mendenhall River is believed to be the result of a combination of factors resulting from localized and region-wide glacial retreat. In addition to a reduction of river stage due to channel incision, a decline in water-table elevations of about 0.6 m during a 17-year period from 1984 to 2001 was identified in an observation well located 250 m from the incising stream channel. Water-table elevations 600 m from the incising channel in the adjacent alluvial outwash aquifer respond in phase to changes in river stage, indicating water-levels in the adjacent aquifer are declining in response to river-channel incision. This study suggests channel incision can rapidly lower water-table elevations for large distances in the adjacent aquifer, potentially modifying the hydrology to a degree capable of influencing adjacent surface-water features, such as off-channel wetlands and flood-plain side channels.

  20. Imaging and spectroscopic observations of a filament channel and the implications for the nature of counter-streamings

    SciTech Connect

    Chen, P. F.; Fang, C.; Harra, L. K.

    2014-03-20

    The dynamics of a filament channel are observed with imaging and spectroscopic telescopes before and during the filament eruption on 2011 January 29. The extreme ultraviolet (EUV) spectral observations reveal that there are no EUV counterparts of the Hα counter-streamings in the filament channel, implying that the ubiquitous Hα counter-streamings found by previous research are mainly due to longitudinal oscillations of filament threads, which are not in phase between each other. However, there exist larger-scale patchy counter-streamings in EUV along the filament channel from one polarity to the other, implying that there is another component of unidirectional flow (in the range of ±10 km s{sup –1}) inside each filament thread in addition to the implied longitudinal oscillation. Our results suggest that the flow direction of the larger-scale patchy counter-streaming plasma in the EUV is related to the intensity of the plage or active network, with the upflows being located at brighter areas of the plage and downflows at the weaker areas. We propose a new method to determine the chirality of an erupting filament on the basis of the skewness of the conjugate filament drainage sites. This method suggests that the right-skewed drainage corresponds to sinistral chirality, whereas the left-skewed drainage corresponds to dextral chirality.

  1. Stream channel cross sections for a reach of the Boise River in Ada County, Idaho

    USGS Publications Warehouse

    Hortness, Jon E.; Werner, Douglas C.

    1999-01-01

    The Federal Emergency Management Agency produces maps of areas that are likely to be inundated during major floods, usually the 100-year, or 1-percent probability, flood. The maps, called Flood Insurance Rate Maps, are used to determine flood insurance rates for homes, businesses, or other structures located in flood-prone areas. State and local governments also use these maps for help with, among other things, development planning and disaster mitigation. During the period October 1997 through December 1998, the initial phase of a hydraulic analysis project of the Boise River from Barber Dam to the Ada/Canyon County boundary, the U.S. Geological Survey collected stream channel cross-section data at 238 locations along the river and documented 108 elevation reference marks established for horizontal and vertical control. In the final phase of the project, the Survey will use these data to determine water-surface elevations for the 10-, 50-, 100-, and 500-year floods and to define floodway limits. The Federal Emergency Management Agency will use the results of this hydraulic analysis to update the 100- and 500-year flood boundaries and the floodway limits on their Flood Insurance Rate Maps.

  2. Larval salamanders and channel geomorphology are indicators of hydrologic permanence in forested headwater streams

    EPA Science Inventory

    Regulatory agencies need rapid indicators of hydrologic permanence for jurisdictional determinations of headwater streams. Our study objective was to assess the utility of larval salamander presence and assemblage structure and habitat variables for determining stream permanence ...

  3. The effect of macropores on bi-directional hydrologic exchange between a stream channel and riparian groundwater

    NASA Astrophysics Data System (ADS)

    Menichino, Garrett T.; Hester, Erich T.

    2015-10-01

    Macropores and soil pipes in stream banks are common geomorphic features. Macropores and soil pipes that are open to the channel (i.e. "bank face-connected" macropores) are inundated when channel stage is elevated (e.g., from precipitation, snowmelt, dam release). However, previous studies have not investigated macropore impact on bi-directional water exchange between the channel and bank/riparian groundwater under variable hydrologic conditions. We monitored two transects of riparian groundwater wells perpendicular to the bank of a 2nd order stream for a year: one with bank face-connected macropores (M transect) and one without bank face-connected macropores (NM transect). Fluctuations in water level and temperature during storms in those wells closest to the channel were on average 139% and 29% higher, respectively, in the presence of macropores. Rising head tests in the same wells indicated that hydraulic conductivity was 61-140 times higher in the presence of macropores. Bank storage, indicated by gradient reversals between channel and riparian zone, occurred on two temporal scales. Bank storage during storms was more frequent in the M transect (occurred all year) than in the NM transect (occurred just in winter and spring). Smaller magnitude gradient reversals at the M transect are consistent with faster head equilibration and greater exchange volume. Bank storage also occurred on an annual basis, with channel water entering storage during summer and fall and returning to the channel during winter and spring. Taken together, these results suggest that macropores act as preferential flow paths that enhance the connectivity between channels and riparian groundwater that influences bank storage. Where bank macropores are present, conceptual models of hyporheic and groundwater flow should account for their effects.

  4. Channel-reach morphology controls of headwater streams based in flysch geologic structures: An example from the Outer Western Carpathians, Czech Republic

    NASA Astrophysics Data System (ADS)

    Galia, Tomáš; Hradecký, Jan

    2014-07-01

    A detailed measurement of 93 channel reaches that were classified with an adjusted Montgomery-Buffington (1997) reach-scale system provided comprehensive information of approximately 9 at-a-reach parameters: the channel gradient, the bankfull width, the bankfull depth, d90, the percentage of resistant rocks in the bed sediment, the number of pieces of large woody debris, valley confinement, direct sediment inputs and the presence of fluvial accumulations in the stream channel. In addition, the quantified intensity of sediment transport (i.e. ratio between sediment supply and transport capacity in longitudinal stream profiles) during flood events has been estimated by the one-dimensional bedload transport model (TOMSED), which was validated in two local streams. The principal component analysis of the at-a-reach parameters did not reveal significant groups of channel-reach morphologies; thus, the selected parameters that exclude sediment transport dynamics within stream longitudinal profile cannot reliably distinguish or predict individual channel reach morphologies. Nevertheless, the channel gradient represented the most significant single explanatory variable for stepped-bed morphologies. The addition of bedload transport parameters demonstrated that limited sediment supply streams and streams with limited transport capacities featured different successions of the channel reach morphologies in terms of the channel gradient and, subsequently, the fluvial continuity. The bedrock-cascades and step-pools were significant for the first case, whereas cascade and step-rapid morphology often occurred in higher sediment supply conditions.

  5. Influences of high-flow events on a stream channel altered by construction of a highway bridge: a case study

    USGS Publications Warehouse

    Hedrick, Lara B.; Welsh, Stuart A.; Anderson, James T.

    2009-01-01

    Impacts of highway construction on streams in the central Appalachians are a growing concern as new roads are created to promote tourism and economic development in the area. Alterations to the streambed of a first-order stream, Sauerkraut Run, Hardy County, WV, during construction of a highway overpass included placement and removal of a temporary culvert, straightening and regrading of a section of stream channel, and armourment of a bank with a reinforced gravel berm. We surveyed longitudinal profiles and cross sections in a reference reach and the altered reach of Sauerkraut Run from 2003 through 2007 to measure physical changes in the streambed. During the four-year period, three high-flow events changed the streambed downstream of construction including channel widening and aggradation and then degradation of the streambed. Upstream of construction, at a reinforced gravel berm, bank erosion was documented. The reference section remained relatively unchanged. Knowledge gained by documenting channel changes in response to natural and anthropogenic variables can be useful for managers and engineers involved in highway construction projects.

  6. Water quality of streams draining abandoned and reclaimed mined lands in the Kantishna Hills area, Denali National Park and Preserve, Alaska, 2008–11

    USGS Publications Warehouse

    Brabets, Timothy P.; Ourso, Robert T.

    2013-01-01

    The Kantishna Hills are an area of low elevation mountains in the northwest part of Denali National Park and Preserve, Alaska. Streams draining the Kantishna Hills are clearwater streams that support several species of fish and are derived from rain, snowmelt, and subsurface aquifers. However, the water quality of many of these streams has been degraded by mining. Past mining practices generated acid mine drainage and excessive sediment loads that affected water quality and aquatic habitat. Because recovery through natural processes is limited owing to a short growing season, several reclamation projects have been implemented on several streams in the Kantishna Hills region. To assess the current water quality of streams in the Kantishna Hills area and to determine if reclamation efforts have improved water quality, a cooperative study between the U.S. Geological Survey and the National Park Service was undertaken during 2008-11. High levels of turbidity, an indicator of high concentrations of suspended sediment, were documented in water-quality data collected in the mid-1980s when mining was active. Mining ceased in 1985 and water-quality data collected during this study indicate that levels of turbidity have declined significantly. Turbidity levels generally were less than 2 Formazin Nephelometric Units and suspended sediment concentrations generally were less than 1 milligram per liter during the current study. Daily turbidity data at Rock Creek, an unmined stream, and at Caribou Creek, a mined stream, documented nearly identical patterns of turbidity in 2009, indicating that reclamation as well as natural revegetation in mined streams has improved water quality. Specific conductance and concentrations of dissolved solids and major ions were highest from streams that had been mined. Most of these streams flow into Moose Creek, which functions as an integrator stream, and dilutes the specific conductance and ion concentrations. Calcium and magnesium are the

  7. Channel morphology and patterns of bedload transport in fluvial, formerly-glaciated, forested headwater streams of the Columbia Mountains, Canada

    NASA Astrophysics Data System (ADS)

    Green, Kim; Brardinoni, Francesco; Alila, Younes

    2013-04-01

    This study examines channel-reach morphology and bedload transport dynamics in relation to landscape structure and snowmelt hydrology in Cotton and Elk Creek, two headwater streams of the southern Columbia Mountains, Canada. Data collection is based on field surveys and GIS analysis in conjunction with a nested monitoring network of water discharge and bed load transfer. The nested monitoring network is designed to examine the effects of channel bed texture, and the influence of free-formed (i.e., boulder cascades, step pools, and riffle pools) and forced-alluvial morphologies (i.e., forced step pools) on bedload entrainment and transport. The landscape is characterized by subdued glaciated topography in which sediment is primarily supplied by bank failures and fluvial transfer dominates the channelized sediment cascade. The spatial distribution of channel types is mainly controlled by glacially imposed local slope together with availability of wood and glacigenic materials. Interestingly, downstream hydraulic geometry as well as downstream patterns of the coarse channel bed fraction and stream power are all insensitive to systematic changes of local slope along the typically stepped longitudinal profiles. An indication that the study alluvial systems are adjusted to the contemporary hydrologic and sedimentary regimes, and as such through post-LGM times have been able to compensate for the glacially-imposed boundary conditions. Stepwise multiple regression indicates that annual bedload yield is chiefly controlled by the number of peak events over threshold discharge. During such high flows, repeated destabilization of channel bed armouring and re-mobilization of sediment stored behind logjams can ensure sediment supply for bedload transport across the entire snowmelt season. In particular, channel morphology affects distinctively the variability of bed load response to hydrologic forcing. The observed spatial variability in annual bedload yield appears to correlate

  8. Using stream sediment lithology to explore the roles of abrasion and channel network structure in shaping downstream sediment yields

    NASA Astrophysics Data System (ADS)

    Mueller, E. R.; Smith, M. E.; Pitlick, J.

    2012-12-01

    Both the flux and characteristics of stream sediment evolve downstream in response to variations in sediment supply, abrasion rate, and channel network structure. We use a simple erosion-abrasion mass balance to model the downstream evolution of sediment flux in two adjacent watersheds draining differing mixtures of soft and resistant rock types in the northern Rocky Mountains. Measurements of bed sediment grain size and lithology are used in conjunction with measured bed load and suspended load sediment fluxes to constrain the model. The results show that the downstream evolution in bed load flux and composition can be strongly influenced by subtle differences in underlying geology, which shapes both the abrasion characteristics and travel path lengths of individual rock types. In the Big Wood basin, abrasion rapidly reduces the size of soft sedimentary and volcanic rocks exposed in headwater areas, concentrating resistant granitic rocks in the stream bed and depressing bed load in favor of suspended load. Alternatively, in the North Fork Big Lost basin, volcanic and sedimentary lithologies are exposed throughout the catchment, and the bed material becomes dominated by erodible but resistant quartzitic sandstones. The result is a much higher bed load flux best modeled with modest abrasion rates. In both cases, the best-fit model can reproduce within 5% the composition of the stream bed substrate using realistic erosion and abrasion parameters. The results also demonstrate a strong linkage between modern hillslopes and channel systems even in these formerly glaciated landscapes, as the sediment signature of the primary streams reflects the systematic tapping of distinct source areas. While this work shows promise, measurement of the spatial patterns in the size and composition of bed and suspended load fluxes at locations throughout a channel network would better elucidate that relative importance of supply, sorting, and abrasion processes.

  9. Annual and seasonal differences in pesticide mixtures within channelized agricultural headwater streams in central Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Only a limited amount of information on pesticide mixtures within agricultural headwater streams is available. A greater understanding of the characteristics of pesticide mixtures and their spatial and temporal trends within agricultural headwater streams is needed to evaluate the risks of pesticid...

  10. Complex channel responses to changes in stream flow and sediment supply on the lower Duchesne River, Utah

    USGS Publications Warehouse

    Gaeuman, D.; Schmidt, J.C.; Wilcock, P.R.

    2005-01-01

    Channel responses to flow depletions in the lower Duchesne River over the past 100 years have been highly complex and variable in space and time. In general, sand-bed reaches adjusted to all perturbations with bed-level changes, whereas the gravel-bed reaches adjusted primarily through width changes. Gravel-bed reaches aggraded only when gravel was supplied to the channel through local bank erosion and degraded only during extreme flood events. A 50% reduction in stream flow and an increase in fine sediment supply to the study area occurred in the first third of the 20th century. The gravel-bed reach responded primarily with channel narrowing, whereas bed aggradation and four large-scale avulsions occurred in the sand-bed reaches. These avulsions almost completely replaced a section of sinuous channel about 14 km long with a straighter section about 7 km long. The most upstream avulsion, located near a break in valley slope and the transition from a gravel bed upstream and a sand bed downstream, transformed a sinuous sand-bed reach into a braided gravel-bed reach and eventually into a meandering gravel-bed reach over a 30-year period. Later, an increase in flood magnitudes and durations caused widening and secondary bed aggradation in the gravel-bed reaches, whereas the sand-bed reaches incised and narrowed. Water diversions since the 1950s have progressively eliminated moderate flood events, whereas larger floods have been less affected. The loss of frequent flooding has increased the duration and severity of drought periods during which riparian vegetation can establish along the channel margins. As a result, the channel has gradually narrowed throughout the study area since the late 1960s, despite the occasional occurrence of large floods. No tributaries enter the Duchesne River within the study area, so all reaches have experienced identical changes in stream flow and upstream sediment supply. ?? 2004 Elsevier B.V. All rights reserved.

  11. Groundwater-derived contaminant fluxes along a channelized Coastal Plain stream

    SciTech Connect

    LaSage, Danita m; Fryar, Alan E; Mukherjee, Abhijit; Sturchio, Neil C; Heraty, Linnea J

    2008-10-01

    Recent studies in various settings across eastern North America have examined the movement of volatile organic compound (VOC) plumes from groundwater to streams, but few studies have addressed focused discharge of such plumes in unlithified sediments. From 1999 through 2002, we monitored concentrations of trichloroethene (TCE) and the non-volatile co-contaminant technetium-99 along Little Bayou Creek, a first -order perennial stream in the Coastal Plain of western Kentucky. Spring flow contributed TCE and technetium-99 to the creek, and TCE concentrations tended to vary with technetium-99 in springs. Contaminant concentrations in stream water fluctuated seasonally, but not always synchronously with stream flow. However, contaminant influxes varied seasonally with stream flow and were dominated by a few springs. Concentrations of O2, NO3⁻, and SO2-4, values of δ37CL in groundwater, and the lack of less-chlorinated ethenes in groundwater and stream water indicated that aerobic biodegradation of TCE was unlikely. Losses of TCE along Little Bayou Creek resulted mainly from volatilization, in contrast to streams receiving diffuse contaminated discharge, where intrinsic bioremediation of VOCs appears to be prevalent.

  12. Development of Relations of Stream Stage to Channel Geometry and Discharge for Stream Segments Simulated with Hydrologic Simulation Program-Fortran (HSPF), Chesapeake Bay Watershed and Adjacent Parts of Virginia, Maryland, and Delaware

    USGS Publications Warehouse

    Moyer, Douglas; Bennett, Mark

    2007-01-01

    The U.S. Geological Survey (USGS), U.S. Environmental Protection Agency (USEPA), Chesapeake Bay Program (CBP), Interstate Commission for the Potomac River Basin (ICPRB), Maryland Department of the Environment (MDE), Virginia Department of Conservation and Recreation (VADCR), and University of Maryland (UMD) are collaborating to improve the resolution of the Chesapeake Bay Regional Watershed Model (CBRWM). This watershed model uses the Hydrologic Simulation Program-Fortran (HSPF) to simulate the fate and transport of nutrients and sediment throughout the Chesapeake Bay watershed and extended areas of Virginia, Maryland, and Delaware. Information from the CBRWM is used by the CBP and other watershed managers to assess the effectiveness of water-quality improvement efforts as well as guide future management activities. A critical step in the improvement of the CBRWM framework was the development of an HSPF function table (FTABLE) for each represented stream channel. The FTABLE is used to relate stage (water depth) in a particular stream channel to associated channel surface area, channel volume, and discharge (streamflow). The primary tool used to generate an FTABLE for each stream channel is the XSECT program, a computer program that requires nine input variables used to represent channel morphology. These input variables are reach length, upstream and downstream elevation, channel bottom width, channel bankfull width, channel bankfull stage, slope of the floodplain, and Manning's roughness coefficient for the channel and floodplain. For the purpose of this study, the nine input variables were grouped into three categories: channel geometry, Manning's roughness coefficient, and channel and floodplain slope. Values of channel geometry for every stream segment represented in CBRWM were obtained by first developing regional regression models that relate basin drainage area to observed values of bankfull width, bankfull depth, and bottom width at each of the 290 USGS

  13. Investigation of Biogeochemical Functional Proxies in Headwater Streams Across a Range of Channel and Catchment Alterations

    NASA Astrophysics Data System (ADS)

    Berkowitz, Jacob F.; Summers, Elizabeth A.; Noble, Chris V.; White, John R.; DeLaune, Ronald D.

    2014-03-01

    Historically, headwater streams received limited protection and were subjected to extensive alteration from logging, farming, mining, and development activities. Despite these alterations, headwater streams provide essential ecological functions. This study examines proxy measures of biogeochemical function across a range of catchment alterations by tracking nutrient cycling (i.e., inputs, processing, and stream loading) with leaf litter fall, leaf litter decomposition, and water quality parameters. Nutrient input and processing remained highest in second growth forests (the least altered areas within the region), while recently altered locations transported higher loads of nutrients, sediments, and conductivity. Biogeochemical functional proxies of C and N input and processing significantly, positively correlated with rapid assessment results (Pearson coefficient = 0.67-0.81; P = 0.002-0.016). Additionally, stream loading equations demonstrate that N and P transport, sediment, and specific conductivity negatively correlated with rapid assessment scores (Pearson coefficient = 0.56-0.81; P = 0.002-0.048). The observed increase in stream loading with lower rapid assessment scores indicates that catchment alterations impact stream chemistry and that rapid assessments provide useful proxy measures of function in headwater ecosystems. Significant differences in nutrient processing, stream loading, water quality, and rapid assessment results were also observed between recently altered (e.g., mined) headwater streams and older forested catchments (Mann-Whitney U = 24; P = 0.01-0.024). Findings demonstrate that biogeochemical function is reduced in altered catchments, and rapid assessment scores respond to a combination of alteration type and recovery time. An analysis examining time and economic requirements of proxy measurements highlights the benefits of rapid assessment methods in evaluating biogeochemical functions.

  14. Riparian-vegetation controls on the spatial pattern of stream-channel instability, Little Piney Creek, Missouri

    USGS Publications Warehouse

    Jacobson, Robert B.; Pugh, Aaron L.

    1998-01-01

    The role of riparian vegetation is assessed quantitatively by using a five-decade record of valley bottom vegetation and channel dynamics developed from historical aerial photography. A 12-kilometer reach of a typical Ozarks stream was mapped using aerial photographs from 1938, 1948, 1955, 1965, 1976, and 1989; maps were then analyzed in a digital geographic information system. Analysis of sequential pairs of maps provides transition frequencies for assessing the relative areal rates at which riparian woodland, grassland, and cropland have been eroded or subjected to gravel aggradation. Results indicate that cropland and grassland have been no more likely to erode than woodland; cropland and grassland are slightly more susceptible to gravel deposition than woodland. These findings underscore the potential for complex responses of streams to a cumulative history of riparian and drainage-basin disturbances.

  15. Counting ion and water molecules in a streaming file through the open-filter structure of the K channel.

    PubMed

    Iwamoto, Masayuki; Oiki, Shigetoshi

    2011-08-24

    The mechanisms underlying the selective permeation of ions through channel molecules are a fundamental issue related to understanding how neurons exert their functions. The "knock-on" mechanism, in which multiple ions in the selectivity filter are hit by an incoming ion, is one of the leading concepts. This mechanism has been supported by crystallographic studies that demonstrated ion distribution in the structure of the Streptomyces lividans (KcsA) potassium channel. These still pictures under equilibrium conditions, however, do not provide a snapshot of the actual, ongoing permeation processes. To understand the dynamics of permeation, we determined the ratio of the ion and water flow [the water-ion coupling ratio (CR(w-i))] through the KcsA channel by measuring the streaming potential (V(stream)) electrophysiologically. The V(stream) value was converted to the CR(w-i) value, which reveals how individual ion and water molecules are queued in the narrow and short filter during permeation. At high K(+) concentrations, the CR(w-i) value was 1.0, indicating that turnover between the alternating ion and water arrays occurs in a single-file manner. At low K(+), the CR(w-i) value was increased to a point over 2.2, suggesting that the filter contained mostly one ion at a time. These average behaviors of permeation were kinetically analyzed for a more detailed understanding of the permeation process. Here, we envisioned the permeation as queues of ion and water molecules and sequential transitions between different patterns of arrays. Under physiological conditions, we predicted that the knock-on mechanism may not be predominant.

  16. Measurement of Channel Morphology in a Headwater Stream using Low-Altitude Photography and a 3D Model Software

    NASA Astrophysics Data System (ADS)

    Nidaira, K.; Hiraoka, M.; Gomi, T.; Uchiyama, Y.

    2015-12-01

    We developed a method for measuring detail channel morphology using a low elevation photographic scanning. This study was conducted in a 36-m step-pool channel segment in a headwater stream of Ooborazawa watershed located in 20 km south of Tokyo. The channels were covered by Boenninghausenia japonica and Oplismenus undulatifolius var. undulatifolius. Therefore, topographic measurement in high altitude (up to 5 m) using a drone is not applicable. D50 and D90 of channel substrates were 4 cm and 21 cm, respectively. A plastic case that equipped with two digital cameras (RICOH CX5) is mounted at the top of 2.2 m of a glass fiber pole. Photos were taken every 5 seconds from 1.8 m above ground surface. Eleven ground control points (GCP) were installed and measured coordinates. We developed digital 3D topographic model using PhotoScan Pro edition version 1.0.0 and the developed 1 cm contour map using ArcGIS version 10.2. Furthermore, we measured the number, height, and length of steps for examining the accuracy of data. Resolution of obtained topographic model was from 9 to 11 mm per pixel. 1 cm of particle was identified using photo was 1 cm. Estimated step height was agreed to the measured step height in the field. We detected maximum channel scour from October to December, 2014 with (146.5 mm/day for maximum daily rain) occurred at pools with 13cm changes , while 5 to 10 cm of changes in sediment deposition occurred from Mya to June, 2015 with 78.5 mm/day of maximum daily rain. Disposition of sediment was concentration within the sequences of step structures. Our method allows us for understanding detail sediment movement and resultant localized channel changes in steep channels.

  17. Distribution of chemical elements in soils and stream sediments in the area of abandoned Sb-As-Tl Allchar mine, Republic of Macedonia.

    PubMed

    Bačeva, Katerina; Stafilov, Trajče; Šajn, Robert; Tănăselia, Claudiu; Makreski, Petre

    2014-08-01

    The aim of this study was to investigate the distribution of some toxic elements in topsoil and subsoil, focusing on the identification of natural and anthropogenic element sources in the small region of rare As-Sb-Tl mineralization outcrop and abandoned mine Allchar known for the highest natural concentration of Tl in soil worldwide. The samples of soil and sediments after total digestion were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Factor analysis (FA) was used to identify and characterize element associations. Six associations of elements were determined by the method of multivariate statistics: Rb-Ta-K-Nb-Ga-Sn-Ba-Bi-Li-Be-(La-Eu)-Hf-Zr-Zn-In-Pd-Ag-Pt-Mg; Tl-As-Sb-Hg; Te-S-Ag-Pt-Al-Sc-(Gd-Lu)-Y; Fe-Cu-V-Ge-Co-In; Pd-Zr-Hf-W-Be and Ni-Mn-Co-Cr-Mg. The purpose of the assessment was to determine the nature and extent of potential contamination as well as to broadly assess possible impacts to human health and the environment. The results from the analysis of the collected samples in the vicinity of the mine revealed that As and Tl elements have the highest median values. Higher median values for Sb are obviously as a result of the past mining activities and as a result of area surface phenomena in the past. PMID:24906071

  18. Distribution of chemical elements in soils and stream sediments in the area of abandoned Sb-As-Tl Allchar mine, Republic of Macedonia.

    PubMed

    Bačeva, Katerina; Stafilov, Trajče; Šajn, Robert; Tănăselia, Claudiu; Makreski, Petre

    2014-08-01

    The aim of this study was to investigate the distribution of some toxic elements in topsoil and subsoil, focusing on the identification of natural and anthropogenic element sources in the small region of rare As-Sb-Tl mineralization outcrop and abandoned mine Allchar known for the highest natural concentration of Tl in soil worldwide. The samples of soil and sediments after total digestion were analyzed by inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-atomic emission spectrometry (ICP-AES). Factor analysis (FA) was used to identify and characterize element associations. Six associations of elements were determined by the method of multivariate statistics: Rb-Ta-K-Nb-Ga-Sn-Ba-Bi-Li-Be-(La-Eu)-Hf-Zr-Zn-In-Pd-Ag-Pt-Mg; Tl-As-Sb-Hg; Te-S-Ag-Pt-Al-Sc-(Gd-Lu)-Y; Fe-Cu-V-Ge-Co-In; Pd-Zr-Hf-W-Be and Ni-Mn-Co-Cr-Mg. The purpose of the assessment was to determine the nature and extent of potential contamination as well as to broadly assess possible impacts to human health and the environment. The results from the analysis of the collected samples in the vicinity of the mine revealed that As and Tl elements have the highest median values. Higher median values for Sb are obviously as a result of the past mining activities and as a result of area surface phenomena in the past.

  19. Using Multiple Watershed-scale Dye Tracing Tests to Study Water and Solute Transport in Naturally Obstructed Stream Channels

    NASA Astrophysics Data System (ADS)

    Jin, L.; Meeks, J. L.; Hubbard, K. A.; Kurian, L. M.; Siegel, D. I.; Lautz, L. K.; Otz, M. H.

    2007-12-01

    Temporary storage of surface water at channel sides and pools significantly affects water and solute transport downstream in watersheds. Beavers, natural "stream channel engineers", build dams which obstruct stream flow and temporarily store water in small to large ponds within stream channels. These ponds substantially delay water movement and increase the water residence time in the system. To study how water and solutes move through these obstructed stream channels, we did multiple dye tracing tests at Cherry Creek, a main tributary to Red Canyon Creek (Wind River Range, Wyoming). First we surveyed beaver dam distributions in detail within the study reaches. We then introduced dyes four times from July 2nd to 6th, 2007 using a scale-up approach. The observation site was fixed at the mouth of Cherry Creek, and 1.5 grams of Rhodamine WT (RWT) dye was injected sequentially at upstream sites with increasing test reach length. The reach lengths scaled up from 500m to 2.5 km. A field fluorometer recorded RWT concentrations every 15 seconds. The results show non-linear decreases of the peak concentration of the dye tracing cloud as the reach scaled up. Also, the times to 1.) the arrivals of the leading edges (Tl), 2.) the peak concentrations (Tp) and 3.) the tailing edges (Tt) and 4) the durations of the tracer cloud (Td) behaved non-linearly as function of length scale. For example, plots of arrivals of leading edges and tailing edges with scale distance appear to define curves of the form; Tl=27.665e1.07× Distance (r2=0.99) and Tt=162.62e0.8551× Distance (r2=0.99), respectively. The greatest non-linearity occurred for the time of tailing and the least for the time of leading edge. These observations are consistent with what would be expected with greater density of dams and/or storage volumes as the reach length increased upgradient. To come to a first approximation, we are currently modeling the breakthrough curves with the solute transport code OTIS to address

  20. Factors controlling the size and shape of stream channels in coarse noncohesive sands

    USGS Publications Warehouse

    Wolman, M. Gordon; Brush, Lucien M.

    1961-01-01

    The size and shape of equilibrium channels in uniform, noncohesive sands, 0.67 mm and 2.0 mm in diameter, were studied experimentally in a laboratory flume 52 feet long in which discharge, slope, sediment load, and bed and bank material could be varied independently. For each run a straight trapezoidal channel was molded in the sand and the flume set at a predetermined slope. Introduction of the discharge was accompanied by widening and aggradation until a stable channel was established. By definition a stable equilibrium existed when channel width, water surface slope, and rate of transport became constant. The duration of individual runs ranged from 2 to 52 hours depending upon the time required for establishing equilibrium. Stability of the banks determined channel shape. In the 2.0 mm sand at a given slope and discharge, only one depth was stable. At this depth the flow was just competent to move particles along the bed of the channel. An increase in discharge produced a wider channel of the same depth and thus transport per unit width remained at a minimum. Channels in the 0.67 mm sand were somewhat more stable and permitted a 1.5 fold increase in depth above that required to start movement of the bed material. An increased transport was associated with the increase in depth. The rate of transport is adequately described in terms of the total shear or in terms of the difference between the total shear and the critical shear required to begin movement. In these experiments the finer, or 0.67 mm, sand, began to move along the bed of the channel at a constant shear stress. Incipient movement of the coarser, or 2.0 mm, sand, varied with the shear stress as well as the mean velocity. At the initiation of movement a lower shear was associated with a higher velocity and vice versa. Anabranches of braided rivers and some natural river channels formed in relatively noncohesive materials resemble the essential characteristics of the flume channels. For a given slope and

  1. Abandoned mine drainage in the Swatara Creek Basin, southern anthracite coalfield, Pennsylvania, USA: 1. stream quality trends coinciding with the return of fish

    USGS Publications Warehouse

    Cravotta, Charles A.; Brightbill, Robin A.; Langland, Michael J.

    2010-01-01

    Acidic mine drainage (AMD) from legacy anthracite mines has contaminated Swatara Creek in eastern Pennsylvania. Intermittently collected base-flow data for 1959–1986 indicate that fish were absent immediately downstream from the mined area where pH ranged from 3.5 to 7.2 and concentrations of sulfate, dissolved iron, and dissolved aluminum were as high as 250, 2.0, and 4.7 mg/L, respectively. However, in the 1990s, fish returned to upper Swatara Creek, coinciding with the implementation of AMD treatment (limestone drains, limestone diversion wells, limestone sand, constructed wetlands) in the watershed. During 1996–2006, as many as 25 species of fish were identified in the reach downstream from the mined area, with base-flow pH from 5.8 to 7.6 and concentrations of sulfate, dissolved iron, and dissolved aluminum as high as 120, 1.2, and 0.43 mg/L, respectively. Several of the fish taxa are intolerant of pollution and low pH, such as river chub (Nocomis icropogon) and longnose dace (Rhinichthys cataractae). Cold-water species such as brook trout (Salvelinus fontinalis) and warm-water species such as rock bass (Ambloplites rupestris) varied in predominance depending on stream flow and stream temperature. Storm flow data for 1996–2007 indicated pH, alkalinity, and sulfate concentrations decreased as the stream flow and associated storm-runoff component increased, whereas iron and other metal concentrations were poorly correlated with stream flow because of hysteresis effects (greater metal concentrations during rising stage than falling stage). Prior to 1999, pH\\5.0 was recorded during several storm events; however, since the implementation of AMD treatments, pH has been maintained near neutral. Flow-adjusted trends for1997–2006 indicated significant increases in calcium; decreases in hydrogen ion, dissolved aluminum, dissolved and total manganese, and total iron; and no change in sulfate or dissolved iron in Swatara Creek immediately downstream from the

  2. Channel morphology and bed-load yield in fluvial, formerly-glaciated headwater streams of the Columbia Mountains, Canada

    NASA Astrophysics Data System (ADS)

    Green, K. C.; Brardinoni, F.; Alila, Y.

    2013-04-01

    This study examines channel-reach morphology and bedload yield dynamics in relation to landscape structure and snowmelt hydrology in headwater streams of the Columbia Mountains, Canada. Data collection relies on field surveys and geographic information systems analysis in conjunction with a nested monitoring network of water discharge and bedload transfer. The landscape is characterized by subdued, formerly-glaciated upland topography in which the geomorphic significance of landslides and debris flows is negligible and fluvial processes prevail. While the spatial organization of channel morphology is chiefly controlled by glacially imposed local slope in conjunction with wood abundance and availability of glacigenic deposits, downstream patterns of the coarse grain-size fraction, bankfull width, bankfull depth, and stream power are all insensitive to systematic changes of local slope along the typically stepped long profiles. This is an indication that these alluvial systems have adjusted to the contemporary snowmelt-driven water and sediment transport regimes, and as such are able to compensate for the glacially-imposed boundary conditions. Bedload specific yield increases with drainage area suggesting that fluvial re-mobilization of glacial and paraglacial deposits dominate the sedimentary dynamics of basins as small as 2 km2. Stepwise multiple regression analysis shows that annual rates of sediment transfer are mainly controlled by the number of peak events over threshold discharge. During such events, repeated destabilization of channel bed armoring and re-mobilization of sediment temporarily stored behind LWD structures can generate bedload transport across the entire snowmelt season. In particular, channel morphology controls the variability of bedload response to hydrologic forcing. In the present case studies, we show that the observed spatial variability in annual bedload yield appears to be modulated by inter-basin differences in morphometric

  3. The influence of stream channels on distributions of Larrea tridentata and Ambrosia dumosa in the Mojave Desert, CA, USA: Patterns, mechanisms and effects of stream redistribution

    USGS Publications Warehouse

    Schwinning, S.; Sandquist, D.R.; Miller, D.M.; Bedford, D.R.; Phillips, S.L.; Belnap, J.

    2011-01-01

    Drainage channels are among the most conspicuous surficial features of deserts, but little quantitative analysis of their influence on plant distributions is available. We analysed the effects of desert stream channels ('washes') on Larrea tridentata and Ambrosia dumosa density and cover on an alluvial piedmont in the Mojave Desert, based on a spatial analysis of transect data encompassing a total length of 2775 m surveyed in 5 cm increments. Significant deviations from average transect properties were identified by bootstrapping. Predictably, shrub cover and density were much reduced inside washes, and elevated above average levels adjacent to washes. Average Larrea and Ambrosia cover and density peaked 1??2-1??6 m and 0??5-1??0 m from wash edges, respectively. We compared wash effects in runon-depleted (-R) sections, where washes had been cut off from runon and were presumably inactive, with those in runon-supplemented (+R) sections downslope from railroad culverts to help identify mechanisms responsible for the facilitative effect of washes on adjacent shrubs. Shrub cover and density near washes peaked in both + R and - R sections, suggesting that improved water infiltration and storage alone can cause a facilitative effect on adjacent shrubs. However, washes of < 2 m width in + R sections had larger than average effects on peak cover, suggesting that plants also benefit from occasional resource supplementation. The data suggest that channel networks significantly contribute to structuring plant communities in the Mojave Desert and their disruption has notable effects on geomorphic and ecological processes far beyond the original disturbance sites. ?? 2010 John Wiley & Sons, Ltd.

  4. Regionalized Equations for Bankfull-Discharge and Channel Characteristics of Streams in New York State - Hydrologic Region 3 East of the Hudson River

    USGS Publications Warehouse

    Mulvihill, Christiane I.; Baldigo, Barry P.

    2007-01-01

    Equations that relate drainage area to bankfull discharge and channel characteristics (such as width, depth, and cross-sectional area) at gaged sites are needed to define bankfull discharge and channel characteristics at ungaged sites and can be used for stream-restoration and protection projects, stream-channel classification, and channel assessments. These equations are intended to serve as a guide for streams in areas of similar hydrologic, climatic, and physiographic conditions. New York State contains eight hydrologic regions that were previously delineated on the basis of high-flow (flood) characteristics. This report presents predictive equations for bankfull characteristics (discharge and channel characteristics) for streams east of the Hudson River, referred to as Hydrologic Region 3. Stream-survey data and discharge records from 12 streamflow-gaging stations were used in regression analyses to relate drainage area to bankfull discharge and bankfull channel width, depth, and cross-sectional area. The four predictive equations are: bankfull discharge (cubic feet per second) = 83.8 (drainage area (square miles))0.679, (1) bankfull-channel width (feet) = 24.0 (drainage area (square miles))0.292, (2) bankfull-channel depth (feet) = 1.66 (drainage area (square miles))0.210, (3) bankfull-channel cross-sectional area (square feet) = 39.8 (drainage area (square miles))0.503. (4) The coefficients of determination (R2) for these four equations are 0.93, 0.85, 0.77, and 0.92, respectively. The high coefficients of determination for bankfull discharge and cross-sectional area indicate that much of the range in the variables is explained by the size of the drainage area; the smaller correlation coefficients for bankfull channel width and depth indicate that other factors also affect these relations. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.16 to 3.35 years; the mean recurrence interval was 2.08 years. The 12 surveyed

  5. Distribution of chemical elements in soils and stream sediments in the area of abandoned Sb–As–Tl Allchar mine, Republic of Macedonia

    SciTech Connect

    Bačeva, Katerina; Stafilov, Trajče; Šajn, Robert; Tănăselia, Claudiu; Makreski, Petre

    2014-08-15

    The aim of this study was to investigate the distribution of some toxic elements in topsoil and subsoil, focusing on the identification of natural and anthropogenic element sources in the small region of rare As–Sb–Tl mineralization outcrop and abandoned mine Allchar known for the highest natural concentration of Tl in soil worldwide. The samples of soil and sediments after total digestion were analyzed by inductively coupled plasma–mass spectrometry (ICP–MS) and inductively coupled plasma–atomic emission spectrometry (ICP–AES). Factor analysis (FA) was used to identify and characterize element associations. Six associations of elements were determined by the method of multivariate statistics: Rb–Ta–K–Nb–Ga–Sn–Ba–Bi–Li–Be–(La–Eu)–Hf–Zr–Zn–In–Pd–Ag–Pt–Mg; Tl–As–Sb–Hg; Te–S–Ag–Pt–Al–Sc–(Gd–Lu)–Y; Fe–Cu–V–Ge–Co–In; Pd–Zr–Hf–W–Be and Ni–Mn–Co–Cr–Mg. The purpose of the assessment was to determine the nature and extent of potential contamination as well as to broadly assess possible impacts to human health and the environment. The results from the analysis of the collected samples in the vicinity of the mine revealed that As and Tl elements have the highest median values. Higher median values for Sb are obviously as a result of the past mining activities and as a result of area surface phenomena in the past. - Highlights: • Soil and river sediments were analyzed from Sb–As–Tl Allchar locality. • An increased content of certain toxic elements for environment was determined. • Highest As and Tl contents are obtained in the close vicinity of Allchar mine. • River sediments portray 160 times higher content of Sb than EU values. • The results classify Allchar as probably the highest natural Tl-deposit worldwide.

  6. Decoding the attended speech stream with multi-channel EEG: implications for online, daily-life applications

    NASA Astrophysics Data System (ADS)

    Mirkovic, Bojana; Debener, Stefan; Jaeger, Manuela; De Vos, Maarten

    2015-08-01

    Objective. Recent studies have provided evidence that temporal envelope driven speech decoding from high-density electroencephalography (EEG) and magnetoencephalography recordings can identify the attended speech stream in a multi-speaker scenario. The present work replicated the previous high density EEG study and investigated the necessary technical requirements for practical attended speech decoding with EEG. Approach. Twelve normal hearing participants attended to one out of two simultaneously presented audiobook stories, while high density EEG was recorded. An offline iterative procedure eliminating those channels contributing the least to decoding provided insight into the necessary channel number and optimal cross-subject channel configuration. Aiming towards the future goal of near real-time classification with an individually trained decoder, the minimum duration of training data necessary for successful classification was determined by using a chronological cross-validation approach. Main results. Close replication of the previously reported results confirmed the method robustness. Decoder performance remained stable from 96 channels down to 25. Furthermore, for less than 15 min of training data, the subject-independent (pre-trained) decoder performed better than an individually trained decoder did. Significance. Our study complements previous research and provides information suggesting that efficient low-density EEG online decoding is within reach.

  7. Channel processes following land use changes in a degrading steep headwater stream in North Island, New Zealand

    NASA Astrophysics Data System (ADS)

    Kasai, Mio

    2006-11-01

    In headwater streams in steep land settings, narrow and steep valley floors provide closely coupled relationships between geomorphic components including hillslopes, tributary fans, and channel reaches. These relationships together with small catchment sizes result in episodic changes to the amount of stored sediment in channels. Major sediment inputs follow high magnitude events. Subsequent exponential losses via removal of material can be represented by a relaxation curve. The influence of hillslope and tributary processes on relaxation curves, and that of altered coupling relations between components, were investigated along a 1.3 km reach of a degrading channel in the 4.8 km 2 Weraamaia Catchment, New Zealand. Extensive deforestation in the late 19th and early 20th centuries, followed by invasion of scrubs and reforestation, induced changes to major erosion types from gully complexes to shallow landslides. Changes in the size and pattern of sediment slugs from 1938 to 2002 were analysed from air photographs tied to detailed field measurement. The rate and calibre of sediment flux changed progressively following substantive hillslope input in a storm in 1938. Subsequently, the channel narrowed and incised, decoupling tributary fans from the main stem, thereby scaling down the size of sediment slugs. As a consequence, the dominant influence on the behaviour of sediment slugs and associated relaxation processes, changed from tributary fans to the type and distribution of bedrock outcrops along the reach.

  8. Reactivation of a cryptobiotic stream ecosystem in the McMurdo Dry Valleys, Antarctica: A long-term geomorphological experiment

    USGS Publications Warehouse

    McKnight, Diane M.; Tate, C.M.; Andrews, E.D.; Niyogi, D.K.; Cozzetto, K.; Welch, K.; Lyons, W.B.; Capone, D.G.

    2007-01-01

    The McMurdo Dry Valleys of Antarctica contain many glacial meltwater streams that flow for 6 to 12??weeks during the austral summer and link the glaciers to the lakes on the valley floors. Dry valley streams gain solutes longitudinally through weathering reactions and microbial processes occurring in the hyporheic zone. Some streams have thriving cyanobacterial mats. In streams with regular summer flow, the mats are freeze-dried through the winter and begin photosynthesizing with the onset of flow. To evaluate the longer term persistence of cyanobacterial mats, we diverted flow to an abandoned channel, which had not received substantial flow for approximately two decades. Monitoring of specific conductance showed that for the first 3??years after the diversion, the solute concentrations were greater in the reactivated channel than in most other dry valley streams. We observed that cyanobacterial mats became abundant in the reactivated channel within a week, indicating that the mats had been preserved in a cryptobiotic state in the channel. Over the next several years, these mats had high rates of productivity and nitrogen fixation compared to mats from other streams. Experiments in which mats from the reactivated channel and another stream were incubated in water from both of the streams indicated that the greater solute concentrations in the reactivated channel stimulated net primary productivity of mats from both streams. These stream-scale experimental results indicate that the cryptobiotic preservation of cyanobacterial mats in abandoned channels in the dry valleys allows for rapid response of these stream ecosystems to climatic and geomorphological change, similar to other arid zone stream ecosystems. ?? 2006 Elsevier B.V. All rights reserved.

  9. Wildfire Impacts on Stream Sedimentation and Channel Morphology: Revisiting the Boulder Creek Burn in Little Granite Creek

    NASA Astrophysics Data System (ADS)

    Ryan, S. E.; Dwire, K. A.; Air, Water,; Aquatic Ecosystems Program

    2011-12-01

    The magnitude of hydrologic and sedimentologic changes observed in watersheds following wildfire depend largely on the severity of the burn, landscape susceptibility to erosion, and the timing and magnitude of storms following the fire. In this study of a burned watershed in NW Wyoming (Boulder Creek burn in Little Granite Creek watershed), sedimentation impacts following a moderately sized fire (burned in 2000) were evaluated against known sediment loads measured prior to burning and against a comparable control watershed. Pre-burn data on rates of sediment transport provide useful information on the inherent variability of stream processes and were used to assess degree of departure due to disturbance from wildfire. Early observations of sediment yield showed substantially elevated rates (5x) the first year post-fire (2001), followed by less elevated rates in 2002 and 2003, signaling a return to baseline values by 3 years post-fire. More recent work, 8 years post-fire, has shown elevated suspended sediment concentrations relative to pre-burn values. We tentatively attribute this increase to destabilization of channels in the burned area due to the introduction of large wood (LW). Surveys indicated that the number of pieces of instream LW were doubled and tripled in some reaches as burned trees began to decay and fall in to the channel. Observed channel changes associated with the introduction of new wood include: 1) increase in the size and number of LW jams; 2) deposition of sediment within LW jams; 3) channel avulsions; 4) erosion of banks and terraces where wood re-directed flow into the bank; and 5) new sources of sediment due to channel instability. These results provide insight into longer-term geomorphic impacts of wildland fire that are associated with LW dynamics and changes to channel and bank stability in the burned riparian environment.

  10. REGIONAL ASSESSMENT OF LAND USE IMPACTS ON STREAM CHANNEL HABITAT IN THE MIDDLE COLUMBIA RIVER BASIN

    EPA Science Inventory

    Many human land uses and land cover modifications (e.g., logging, grazing, roads) tend to increase erosion, leading to an increase in fine sediment supplied to streams and potentially degrading aquatic habitat for benthic organisms. This study evaluated potential human impacts o...

  11. Influence of instream habitat and water quality on aggressive behavior in crayfish of channelized headwater streams

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many agricultural drainage ditches that border farm fields of the Midwestern United States are degraded headwater streams that possess communities of crayfish. We hypothesized that crayfish communities at sites with low instream habitat diversity and poor water quality would show greater evidence of...

  12. Effects of fire and subsequent channel-reorganizing events on invertebrate drift and rainbow trout diet in small headwater streams 10 years post-disturbance

    NASA Astrophysics Data System (ADS)

    Rosenberger, A. E.; Dunham, J. B.; Wipfli, M. S.; Buffington, J. M.

    2005-05-01

    Studies examining the effects of fire on the biota of streams are often confined to immediate post-disturbance impacts; however it is also important to consider longer-term effects of fire and fire-related channel disturbances, including both negative and positive influences on stream communities. Fire and subsequent debris flows and hyperconcentrated flows destroy streamside vegetation and alter the channel morphology such that streams are wider and shallower with larger, less mobile substrate. Increased light, high temperatures, and altered stream morphology have the potential to greatly impact invertebrate communities, invertebrate drift, and drift-feeding fish diet. The goal of our study was to determine the effects of wildfire and wildfire-related disturbance on the amount and composition of stream invertebrate drift and how that translates to the diet of resident fishes 10 years post-disturbance. In the summer and fall of 2003, we set drift nets and examined the diet of fishes in 9 streams: 3 unburned; 3 burned (1992-4); and 3 burned with a subsequent channel disturbance (1992-4). Key questions include: does the taxonomic composition (richness, functional feeding groups), origin (terrestrial or aquatic), or total production (biomass) of invertebrate drift and fish diet vary with burn history? Does the composition and biomass of invertebrate drift indicate main sources of energy (allochthonous vs. autochthonous) for headwater streams affected by fire? Differences among streams in channel morphology, streamside vegetation, light input, and temperature did not correspond to consistent or marked differences in invertebrate drift productivity and only slight differences in functional feeding group composition. However, preliminary data suggest that taxon richness, though similar among burned and unburned streams, is lowest in burned and disturbed streams. Although there is a terrestrial component to fish diet in all three treatment groups, in the summer, there is

  13. Hydraulic and channel characteristics of selected streams in the Kantishna Hills area, Denali National Park and Preserve, Alaska, 1982-84

    USGS Publications Warehouse

    Van Maanen, J.L.; Solin, G.L.

    1988-01-01

    The Kantishna Hills area of the Denali National Park and Preserve contains extensive placer gold deposits. In order to develop plans for the management of this natural resource, and to assess the effects of placer mining on aquatic systems, documentation of the physical characteristics of the streams in the area is needed. Channel morphology, streamflow and streambed composition data were collected at 14 stream reaches in the Kantishna Hills area in September 1982 and in June, July, August , and September of 1983 and 1984. The reaches selected include locations of historical and current mining activity and locations which are undisturbed. The data indicate only minor differences in the physical properties of the streams in mined and unmined drainage basins. The composition of streambeds below mined areas tended to consist of finer sized particles and exhibited less variation in mean particle size than streambed in unmined basins. This may be due in part to the natural sorting of material in stream channels because mined areas, and thus study reaches below them, tended to be located relatively farther downstream (nearer the stream mouth) than were study reaches in basins where no mining has occurred. Changes in the physical properties of the streams which could be directly attributed to mining activity were noted at only one location, Rainy Creek near Kantishna, where the stream had been diverted from its natural channel by the construction of settling ponds. (Author 's abstract)

  14. Influences of wildfire and channel reorganization on spatial and temporal variation in stream temperature and the distribution of fish and amphibians

    USGS Publications Warehouse

    Dunham, J.B.; Rosenberger, A.E.; Luce, C.H.; Rieman, B.E.

    2007-01-01

    Wildfire can influence a variety of stream ecosystem properties. We studied stream temperatures in relation to wildfire in small streams in the Boise River Basin, located in central Idaho, USA. To examine the spatio-temporal aspects of temperature in relation to wildfire, we employed three approaches: a pre-post fire comparison of temperatures between two sites (one from a burned stream and one unburned) over 13 years, a short-term (3 year) pre-post fire comparison of a burned and unburned stream with spatially extensive data, and a short-term (1 year) comparative study of spatial variability in temperatures using a "space for time" substitutive design across 90 sites in nine streams (retrospective comparative study). The latter design included streams with a history of stand-replacing wildfire and streams with severe post-fire reorganization of channels due to debris flows and flooding. Results from these three studies indicated that summer maximum water temperatures can remain significantly elevated for at least a decade following wildfire, particularly in streams with severe channel reorganization. In the retrospective comparative study we investigated occurrence of native rainbow trout (Oncorhynchus mykiss) and tailed frog larvae (Ascaphus montanus) in relation to maximum stream temperatures during summer. Both occurred in nearly every site sampled, but tailed frog larvae were found in much warmer water than previously reported in the field (26.6??C maximum summer temperature). Our results show that physical stream habitats can remain altered (for example, increased temperature) for many years following wildfire, but that native aquatic vertebrates can be resilient. In a management context, this suggests wildfire may be less of a threat to native species than human influences that alter the capacity of stream-living vertebrates to persist in the face of natural disturbance. ?? 2007 Springer Science+Business Media, LLC.

  15. Sediment Mobilization and Storage Dynamics of a Debris Flow Impacted Stream Channel using Multi-Temporal Structure from Motion Photogrammetry

    NASA Astrophysics Data System (ADS)

    Bailey, T. L.; Sutherland-Montoya, D.

    2015-12-01

    High resolution topographic analysis methods have become important tools in geomorphology. Structure from Motion photogrammetry offers a compelling vehicle for geomorphic change detection in fluvial environments. This process can produce arbitrarily high resolution, geographically registered spectral and topographic coverages from a collection of overlapping digital imagery from consumer cameras. Cuneo Creek has had three historically observed episodes of rapid aggradation (1955, 1964, and 1997). The debris flow deposits continue to be major sources of sediment sixty years after the initial slope failure. Previous studies have monitored the sediment storage volume and particle size since 1976 (in 1976, 1982, 1983, 1985, 1986, 1987, 1998, 2003). We reoccupied 3 previously surveyed stream cross sections on Sept 30, 2014 and March 30, 2015, and produced photogrammetric point clouds using a pole mounted camera with a remote view finder to take nadir view images from 4.3 meters above the channel bed. Ground control points were registered using survey grade GPS and typical cross sections used over 100 images to build the structure model. This process simultaneously collects channel geometry and we used it to also generate surface texture metrics, and produced DEMs with point cloud densities above 5000 points / m2. In the period between the surveys, a five year recurrence interval discharge of 20 m3/s scoured the channel. Surface particle size distribution has been determined for each observation period using image segmentation algorithms based on spectral distance and compactness. Topographic differencing between the point clouds shows substantial channel bed mobilization and reorganization. The net decline in sediment storage is in excess of 4 x 10^5 cubic meters since the 1964 aggradation peak, with associated coarsening of surface particle sizes. These new methods provide a promising rapid assessment tool for measurement of channel responses to sediment inputs.

  16. Wildfire, channel disturbance, and stream temperature: spatio-temporal patterns and associations with the distribution of fish and amphibians in central Idaho

    NASA Astrophysics Data System (ADS)

    Dunham, J. B.; Luce, C. H.; Rosenberger, A. E.; Gutierrez, B.; Nagel, D. E.; Rieman, B. E.

    2005-05-01

    Temperature is a critical factor in stream ecosystems, and one that is very likely to be altered by wildfire and associated channel disturbance. In central Idaho streams, temperatures after wildfires may increase following loss of shade from riparian vegetation, and changes in channel structure that increase exposure to solar radiation and decreased hyporheic exchanges. To examine the spatio-temporal aspects temperature in relation to these influences, we employed three approaches: a long-term pre-post fire comparison of temperatures between a pair of streams, one burned and one unburned; a short-term pre-post fire comparison of a burned and unburned stream with spatially extensive data; a short-term comparative study of spatial variability in temperatures using a "space for time" substitutive design. These three approaches provided key insights into the value of each study approach and revealed some expected and some surprising associations between temperature and occurrence of native trout and tailed frogs. To further understand potential mechanisms influencing stream temperature, we used field-validated estimates of solar radiation to model the effects of riparian shade from remotely sensed vegetation data. These models confirmed the importance of riparian influences linked to wildfire for stream temperature in our study system. The collective results of this work highlight the importance of spatio-temporal variability in study designs to quantify the effects of wildfire and disturbance on stream temperatures, and the implications of stream temperature for aquatic species in a broad landscape context.

  17. The role of water exchange between a stream channel and its hyporheic zone in nitrogen cycling at the terrestrial-aquatic interface

    USGS Publications Warehouse

    Triska, F.J.; Duff, J.H.; Avanzino, R.J.

    1993-01-01

    The subsurface riparian zone was examined as an ecotone with two interfaces. Inland is a terrestrial boundary, where transport of water and dissolved solutes is toward the channel and controlled by watershed hydrology. Streamside is an aquatic boundary, where exchange of surface water and dissolved solutes is bi-directional and flux is strongly influenced by channel hydraulics. Streamside, bi-directional exchange of water was qualitatively defined using biologically conservative tracers in a third order stream. In several experiments, penetration of surface water extended 18 m inland. Travel time of water from the channel to bankside sediments was highly variable. Subsurface chemical gradients were indirectly related to the travel time. Sites with long travel times tended to be low in nitrate and DO (dissolved oxygen) but high in ammonium and DOC (dissolved organic carbon). Sites with short travel times tended to be high in nitrate and DO but low in ammonium and DOC. Ammonium concentration of interstitial water also was influenced by sorption-desorption processes that involved clay minerals in hyporheic sediments. Denitrification potential in subsurface sediments increased with distance from the channel, and was limited by nitrate at inland sites and by DO in the channel sediments. Conversely, nitrification potential decreased with distance from the channel, and was limited by DO at inland sites and by ammonium at channel locations. Advection of water and dissolved oxygen away from the channel resulted in an oxidized subsurface habitat equivalent to that previously defined as the hyporheic zone. The hyporheic zone is viewed as stream habitat because of its high proportion of surface water and the occurrence of channel organisms. Beyond the channel's hydrologic exchange zone, interstitial water is often chemically reduced. Interstitial water that has not previously entered the channel, groundwater, is viewed as a terrestrial component of the riparian ecotone. Thus

  18. Exploring geomorphic controls on fish bioenergetics in mountain streams: linkages between channel morphology and rearing habitat for cutthroat trout

    NASA Astrophysics Data System (ADS)

    Cienciala, P.; Hassan, M. A.

    2013-12-01

    Landscape heterogeneity constitutes an important control on spatial distribution of habitat for living organisms, at a range of spatial scales. For example, spatial variation in geomorphic processes can spatially structure populations as well as entire communities, and affect various ecosystem processes. We have coupled a 2D hydrodynamic model with a bioenergetic model to study the effects of various channel morphologies and bed textures on rearing habitat for coastal cutthroat trout (Oncorhynchus clarki clarki) in four reaches of a mountain stream. The bioenergetic model uses energy conservation principle to calculate energy budget for fish at any point of the study domain, given a set of relevant local conditions. Specifically, the energy intake is a function of food availability (invertebrate drift) while the energy expenditure occurs through, for example, basal metabolism and swimming to hold position against the flow. Channel morphology and bed texture, through their influence on channel hydraulics, can exert strong control on the spatial pattern of both food flux and swimming cost for drift-feeding fish. Therefore, the coupled hydrodynamic and bioenergetic models, parameterized using an extensive field data set, enabled us to explore mechanistic linkages between geomorphic properties of the study reaches, food resource availability, and the energetic profitability of rearing habitat for different age-classes at both between- and within-reach spatial scales.

  19. Assessment of channel changes in a Mediterranean ephemeral stream since the early twentieth century. The Rambla de Cervera, eastern Spain

    NASA Astrophysics Data System (ADS)

    Segura-Beltrán, Francisca; Sanchis-Ibor, Carles

    2013-11-01

    An analysis of morphological changes during the last six decades is presented for a 16.5-km reach of the Rambla de Cervera, a Mediterranean ephemeral stream located in eastern Spain. Channel changes were analysed through a range of techniques, specifically the analysis of aerial photographs with geographical information systems (GIS) and comparison of topographic surveys. The gravel channel underwent a general decline over the study period, losing width (68.5%) and surface area (45.7%) caused by the development of established islands frequently attached to the floodplain. These morphological changes exhibit an interesting temporal variability, with a maximum decrease of the gravel channel in the period 1946-1956 and another narrowing stage between 1977 and 1991. Two periods (1956-1977 and 1991-2006) also had mixed performance. In addition, incision processes occurred along the entire study reach at an average depth of 3.5 m. Natural and human-induced factors producing contradictory effects are considered responsible for changes in the Rambla de Cervera.

  20. The use of stream flow routing for direct channel precipitation with isotopically-based hydrograph separations: the role of new water in stormflow generation

    NASA Astrophysics Data System (ADS)

    Renshaw, Carl E.; Feng, Xiahong; Sinclair, Kelsey J.; Dums, Raymond H.

    2003-03-01

    Understanding the pathways by which event water contributes to stream stormflow provides insight into stormflow generation mechanisms. We analyze the impact of storm size on the relative contribution of event water to stormflow by using natural variations in the oxygen isotopic composition of precipitation and stream water to separate multiple stormflow hydrographs from a single fourth-order, 1212 ha catchment. We extend previous isotope-based hydrograph separations by independently accounting for the contribution of event water via direct channel precipitation to the stream hydrograph. The direct channel precipitation contribution is determined using a numerical model of stream flow routing though the catchment, taking precipitation and digital elevation data as input variables. For the range of storm sizes sampled, having recurrence intervals ranging from less than a week to ˜4 months, essentially all the event water in stream stormflow can be attributed to direct channel precipitation. Event water not directly falling on the stream channel indirectly contributes to stormflow by increasing the subsurface discharge of pre-event water to the stream. Neither the hydrograph separation data, field observations during the precipitation events, nor experimental observations of flow in a large-scale natural soil column extracted from the watershed are consistent with macropore flow or groundwater ridging as the primary mechanism responsible for increasing subsurface discharge. Results from a series of artificial rain experiments using the unsaturated natural soil column are consistent with a preferential kinematic flow model and indicate that the discharge of pre-event water to the stream during a storm event may be controlled by kinematic flow processes within the watershed soils.

  1. Hydraulic modeling of stream channels and structures in Harbor and Crow Hollow Brooks, Meriden, Connecticut

    USGS Publications Warehouse

    Weiss, Lawrence A.; Sears, Michael P.; Cervione, Michael A.

    1994-01-01

    Effects of urbanization have increased the frequency and size of floods along certain reaches of Harbor Brook and Crow Hollow Brook in Meriden, Conn. A floodprofile-modeling study was conducted to model the effects of selected channel and structural modifications on flood elevations and inundated areas. The study covered the reach of Harbor Brook downstream from Interstate 691 and the reach of Crow Hollow Brook downstream from Johnson Avenue. Proposed modifications, which include changes to bank heights, channel geometry, structural geometry, and streambed armoring on Harbor Brook and changes to bank heights on Crow Hollow Brook, significantly lower flood elevations. Results of the modeling indicate a significant reduction of flood elevations for the 10-year, 25-year, 35-year, 50-year, and 100-year flood frequencies using proposed modifications to (1 ) bank heights between Harbor Brook Towers and Interstate 691 on Harbor Brook, and between Centennial Avenue and Johnson Avenue on Crow Hollow Brook; (2) channel geometry between Coe Avenue and Interstate 69 1 on Harbor Brook; (3) bridge and culvert opening geometry between Harbor Brook Towers and Interstate 691 on Harbor Brook; and (4) channel streambed armoring between Harbor Brook Towers and Interstate 691 on Harbor Brook. The proposed modifications were developed without consideration of cost-benefit ratios.

  2. Channel response to tectonic forcing: field analysis of stream morphology and hydrology in the Mendocino triple junction region, northern California

    NASA Astrophysics Data System (ADS)

    Snyder, Noah P.; Whipple, Kelin X.; Tucker, Gregory E.; Merritts, Dorothy J.

    2003-07-01

    An empirical calibration of the shear stress model for bedrock incision is presented, using field and hydrologic data from a series of small, coastal drainage basins near the Mendocino triple junction in northern California. Previous work comparing basins from the high uplift zone (HUZ, uplift rates around 4 mm/year) to ones in the low uplift zone (LUZ, ˜0.5 mm/year) indicates that the HUZ channels are about twice as steep for a given drainage area. This observation suggests that incision processes are more effective in the HUZ. It motivates a detailed field study of channel morphology in the differing tectonic settings to test whether various factors that are hypothesized to influence incision rates (discharge, channel width, lithology, sediment load) change in response to uplift or otherwise differ between the HUZ and LUZ. Analysis of regional stream gaging data for mean annual discharge and individual floods yields a linear relationship between discharge and drainage area. Increased orographic precipitation in the HUZ accounts for about a twofold increase in discharge in this area, corresponding to an assumed increase in the erosional efficiency of the streams. Field measurements of channel width indicate a power-law relationship between width and drainage area with an exponent of ˜0.4 and no significant change in width between the uplift rate zones, although interpretation is hampered by a difference in land use between the zones. The HUZ channel width dataset reveals a scaling break interpreted to be the transition between colluvial- and fluvial-dominated incision processes. Assessments of lithologic resistance using a Schmidt hammer and joint surveys show that the rocks of the study area should be fairly similar in their susceptibility to erosion. The HUZ channels generally have more exposed bedrock than those in the LUZ, which is consistent with protection by sediment cover inhibiting incision in the LUZ. However, this difference is likely the result of a

  3. An Alternative to Channel-Centered Views of the Landscape for Understanding Modern Streams in the Mid-Atlantic Piedmont Region, Eastern USA

    NASA Astrophysics Data System (ADS)

    Merritts, D. J.; Walter, R. C.; Rahnis, M. A.; Oberholtzer, W.

    2008-12-01

    Stream channels generally are the focus of conceptual models of valley bottom geomorphology. The channel-centered model prevalent in the tectonically inactive eastern U. S. invokes meandering stream channels migrating laterally across valley floors, eroding one bank while depositing relatively coarse sediment in point bars on the other. According to this model, overbank deposition during flooding deposits a veneer of fine sediment over the gravel substrate. Erosion is considered normal, and the net volume of sediment is relatively constant with time. A dramatic change in conditions-land-clearing during European settlement--led to widespread aggradation on valley bottoms. This historic sedimentation was incorporated in the channel-centered view by assuming that meandering streams were overwhelmed by the increased sediment load and rapidly aggraded vertically. Later, elevated stream channels cut through these deposits because of decreased sediment supply and increased stormwater runoff accompanying urbanization. This view can be traced to early ideas of stream equilibrium in which incoming sediment supply and runoff determine stream-channel form. We propose a different conceptual model. Our trenching and field work along hundreds of km of stream length in the mid-Atlantic Piedmont reveal no point bars prior to European settlement. Instead, a polygenetic valley-bottom landscape underlies the drape of historic sediment. The planar surface of this veneer gives the appearance of a broad floodplain generated by long-term meandering and overbank deposition, but the "floodplain" is a recent aggradational surface from regional base-level rise due to thousands of early American dams that spanned valley bottoms. As modern streams incise into the historic fine-grained slackwater sediment, they expose organic-rich hydric soils along original valley bottom centers; talus, colluvium, bedrock, and saprolite with forest soils along valley margins; and weathered Pleistocene (and

  4. Ice in Channels and Ice-Rock Mixtures in Valleys on Mars: Did They Slide on Deformable Rubble Like Antarctic Ice Streams?

    NASA Technical Reports Server (NTRS)

    Lucchitta, B. K.

    1997-01-01

    Recent studies of ice streams in Antarctica reveal a mechanism of basal motion that may apply to channels and valleys on Mars. The mechanism is sliding of the ice on deformable water-saturated till under high pore pressures. It has been suggested by Lucchitta that ice was present in outflow channels on Mars and gave them their distinctive morphology. This ice may have slid like Antarctic ice streams but on rubbly weathering products rather than till. However, to generate water under high pore pressures, elevated heatflow is needed to melt the base of the ice. Either volcanism or higher heatflow more than 2 b.y. ago could have raised the basal temperature. Regarding valley networks, higher heatflow 3 b.y. ago could have allowed sliding of ice-saturated overburden at a few hundred meters depth. If the original, pristine valleys were somewhat deeper than they are now, they could have formed by the same mechanism. Recent sounding of the seafloor in front of the Ross Ice Shelf in Antarctica reveals large persistent patterns of longitudinal megaflutes and drumlinoid forms, which bear remarkable resemblance to longitudinal grooves and highly elongated streamlined islands found on the floors of martian outflow channels. The flutes are interpreted to have formed at the base of ice streams during the last glacial advance. Additional similarities of Antarctic ice streams with martian outflow channels are apparent. Antarctic ice streams are 30 to 80 km wide and hundreds of kilometers long. Martian outflow channels have similar dimensions. Ice stream beds are below sea level. Carr determined that most common floor elevations of martian outflow channels lie below martian datum, which may have been close to or below past martian sea levels. The Antarctic ice stream bed gradient is flat and locally may go uphill, and surface slopes are exceptionally. Martian channels also have floor gradients that are shallow or go uphill locally and have low surface gradients. The depth to the

  5. Erosion, sediment discharge, and channel morphology in the upper Chattahoochee River basin, Georgia, with a discussion of the contribution of suspended sediment to stream quality

    USGS Publications Warehouse

    Faye, Robert E.; Carey, W.P.; Stamer, J.K.; Kleckner, R.L.

    1980-01-01

    The 3,550 square miles of the Upper Chattahoochee River basin is an area of diverse physiographic and land-use characteristics. The headwater areas are mountainous with steep, relatively narrow channels. Land in the headwater areas is heavily forested, but small towns and farms are common in the valleys of large streams. Downstream, the basin is characterized by low hills and wider stream channels. Land in this part of the basin is also predominantly forested; however, large agricultural and urban areas are common. Urban land use is particularly intensive within the Atlanta Metropolitan Area.

  6. Relationships of elevation, channel slope, and stream width to occurrences of native fishes at the Great Plains-Rocky Mountains interface

    USGS Publications Warehouse

    Brunger, Lipsey T.S.; Hubert, W.A.; Rahel, F.J.

    2005-01-01

    Environmental gradients occur with upstream progression from plains to mountains and affect the occurrence of native warmwater fish species, but the relative importance of various environmental gradients are not defined. We assessed the relative influences of elevation, channel slope, and stream width on the occurrences of 15 native warmwater fish species among 152 reaches scattered across the North Platte River drainage of Wyoming at the interface of the Great Plains and Rocky Mountains. Most species were collected in reaches that were lower in elevation, had lower channel slopes, and were wider than the medians of the 152 sampled reaches. Several species occurred over a relatively narrow range of elevation, channel slope, or stream width among the sampled reaches, but the distributions of some species appeared to extend beyond the ranges of the sampled reaches. We identified competing logistic-regression models that accounted for the occurrence of individual species using the information-theoretic approach. Linear logistic-regression models accounted for patterns in the data better than curvilinear models for all species. The highest ranked models included channel slope for seven species, elevation for six species, stream width for one species, and both channel slope and stream width for one species. Our results suggest that different environmental gradients may affect upstream boundaries of different fish species at the interface of the Great Plains and Rocky Mountains in Wyoming.

  7. Response of fish populations to natural channel design restoration in streams of the Catskill Mountains, New York

    USGS Publications Warehouse

    Baldigo, Barry P.; Warren, D.R.; Ernst, A.G.; Mulvihill, C.I.

    2008-01-01

    Many streams and rivers throughout North America have been extensively straightened, widened, and hardened since the middle 1800s, but related effects on aquatic ecosystems have seldom been monitored, described, or published. Beginning in the early 1990s, reach-level restoration efforts began to base projects on natural channel design (NCD) techniques and Rosgen's (1994b, 1996) river classification system in an effort to duplicate or mimic stable reference reach geomorphology. Four reaches in three streams of the Catskill Mountains, New York, were restored from 2000 to 2002 using NCD techniques to decrease bed and bank erosion rates, decrease sediment loads, and improve water quality. The effects of restoration on the health of fish assemblages were assessed through a before-after, control-impact (BACI) study design to quantify the net changes in population and community indices at treatment reaches relative to index changes at unaltered reference reaches from 1999 to 2004. After restoration, community richness and biomass at treatment reaches increased by more than one-third. Changes in fish communities were caused mainly by shifts in dominant species populations; fish community biomass and total fish abundance were generally dominated by daces or daces and sculpins before restoration and by one or more salmonid species after restoration. Density and biomass of eastern blacknose dace Rhinichthys atratulus, longnose dace R. cataractae, and slimy sculpin Cottus cognatus did not change appreciably, whereas net salmonid density and biomass increased substantially after restoration. These changes were driven primarily by large increases in populations of brown trout Salmo trutta. The findings demonstrate that the structure, function, and ultimately the health of resident fish populations and communities can be improved, at least over the short term, through NCD restoration in perturbed streams of the Catskill Mountains. ?? Copyright by the American Fisheries Society

  8. Recharge of shallow aquifers through two ephemeral-stream channels in northeastern Wyoming, 1982-1983

    USGS Publications Warehouse

    Lenfest, L.W.

    1987-01-01

    Quantifying the recharge from ephemeral streams to alluvial and bedrock aquifers will help evaluate the effects of surface mining on alluvial valley floors in Wyoming. Two stream reaches were chosen for study in the Powder River basin. One reach was located along the North Fork Dry Fork Cheyenne River near Glenrock, Wyoming, and the other reach was located along Black Thunder Creek near Hampshire, Wyoming. The reach along the North Fork Dry Fork Cheyenne River was instrumented with 3 gaging stations to measure streamflow and with 6 observation wells to measure groundwater level fluctuations in alluvial and bedrock aquifers in response to streamflow. The 3 streamflow gaging stations were located within the 2.5-mi study reach to measure the approximate gain or loss of discharge along the reach. Computed streamflow losses ranged from 0.43 acre-ft/mi on July 9 , 1982, to 1.44 acre-ft/mi on August 9, 1982. The observation wells completed only in the alluvial aquifer were dry during flow in the North Fork Dry Fork Cheyenne River, whereas water levels in half of the observation wells completed in the bedrock aquifers or the alluvial and bedrock aquifers rose in response to flow in the North Fork Dry Fork Cheyenne River. Groundwater recharge on August 9, 1982, was calculated using a convolution technique using groundwater levels at the upstream site and was estimated to be 26.5 acre-ft/mi. The reach along Black Thunder Creek was instrumented with one gaging station to measure streamflow and with 4 observation wells to measure water level response in alluvial and bedrock aquifers to streamflow. Recharge to the alluvial aquifer from flow in Black Thunder Creek ranged from 3.56 to 12.4 acre-ft/mi. The recharge was estimated using the convolution technique using water level measurements in the observation wells completed in the alluvial aquifer. Water level measurements in the observation wells indicated water level rises in the alluvial and bedrock aquifers in response to

  9. Regional Relations in Bankfull Channel Characteristics determined from flow measurements at selected stream-gaging stations in West Virginia, 1911-2002

    USGS Publications Warehouse

    Messinger, Terence; Wiley, Jeffrey B.

    2004-01-01

    Three bankfull channel characteristics?cross-sectional area, width, and depth?were significantly correlated with drainage area in regression equations developed for two regions in West Virginia. Channel characteristics were determined from analysis of flow measurements made at 74 U.S. Geological Survey stream-gaging stations at flows between 0.5 and 5.0 times bankfull flow between 1911 and 2002. Graphical and regression analysis were used to delineate an 'Eastern Region' and a 'Western Region,' which were separated by the boundary between the Appalachian Plateaus and Valley and Ridge Physiographic Provinces. Streams that drained parts of both provinces had channel characteristics typical of the Eastern Region, and were grouped with it. Standard error for the six regression equations, three for each region, ranged between 8.7 and 16 percent. Cross-sectional area and depth were greater relative to drainage area for the Western Region than they were for the Eastern Region. Regression equations were defined for streams draining between 46.5 and 1,619 square miles for the Eastern Region, and between 2.78 and 1,354 square miles for the Western Region. Stream-gaging stations with two or more cross sections where flow had been measured at flows between 0.5 and 5.0 times the 1.5-year flow showed poor replication of channel characteristics compared to the 95-percent confidence intervals of the regression, suggesting that within-reach variability for the stream-gaging stations may be substantial. A disproportionate number of the selected stream-gaging stations were on large (drainage area greater than 100 square miles) streams in the central highlands of West Virginia, and only one stream-gaging station that met data-quality criteria was available to represent the region within about 50 miles of the Ohio River north of Parkersburg, West Virginia. Many of the cross sections were at bridges, which can change channel shape. Although the data discussed in this report may not be

  10. Wildfire, channel disturbance, and stream temperature: spatio-temporal patterns and associations with the distribution of fish and amphibians in central Idaho

    NASA Astrophysics Data System (ADS)

    Dunham, J.; Luce, C.; Rosenberger, A.; Rieman, B.

    2005-12-01

    Temperature is a critical factor in stream ecosystems, and one that is altered by wildfire and related channel disturbances. In central Idaho streams, temperatures after wildfires may increase following loss of shade from riparian vegetation, and changes in channel structure that increase exposure to solar radiation and decreased hyporheic exchanges. To examine the spatio-temporal aspects temperature in relation to these influences, we employed three approaches: a long-term pre-post fire comparison of temperatures between a pair of streams, one burned and one unburned; a short-term pre-post fire comparison of a burned and unburned stream with spatially extensive data; and a short-term comparative study of spatial variability in temperatures using a space for time substitutive design. These three approaches provided key insights into the value of each study approach and revealed some expected and some surprising associations between temperature and occurrence of native trout and tailed frogs. The results of this work highlight the importance of spatio-temporal variability in study designs to quantify the effects of wildfire and disturbance on stream temperatures, and the implications of stream temperature for aquatic species in a broad landscape context.

  11. Regionalized Equations for Bankfull Discharge and Channel Characteristics of Streams in New York State - Hydrologic Regions 1 and 2 in the Adirondack Region of Northern New York

    USGS Publications Warehouse

    Mulvihill, Christiane I.; Filopowicz, Amy; Coleman, Arthur; Baldigo, Barry P.

    2007-01-01

    Equations that relate drainage area to bankfull discharge and channel characteristics (width, depth, and cross-sectional area) at gaged sites are needed to define bankfull-discharge and channel characteristics at ungaged sites and to provide information for watershed assessments, stream-channel classification, and design of stream-restoration projects. Such equations are most accurate if derived from streams within an area of uniform hydrologic, climatic, and physiographic conditions and applied only within that region. Stream-survey and discharge data from 15 active (currently gaged in 2005) streamflow-gaging stations and 1 inactive (discontinued) streamflow-gaging station in hydrologic Regions 1 and 2 were used in linear-regression analyses to relate drainage area to bankfull discharge and bankfull-channel width, depth, and cross-sectional area. The four resulting equations are the following: 1) bankfull discharge (cubic feet per second) 2) bankfull-channel width (feet) 3) bankfull-channel depth (feet) 4) bankfull-channel cross-sectional area (square feet) The coefficients of determination (R2) for these four equations are 0.95, 0.89, 0.89, and 0.97, respectively. The high coefficients of determination for these equationsindicate that much variability is explained by drainage area. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.01 to 3.80 years; the mean recurrence interval was 2.13 years. The 16 surveyed streams were classified by Rosgen stream type; most were B- and C-type, with a few E- and F-type cross sections. The hydrologic Regions 1 and 2 equation for the relation between bankfull discharge and drainage area was graphically compared to curves developed for 5 other hydrologic regions in New York State. The 95-percent confidence interval for the hydrologic Regions 1 and 2 curve fully encompassed the curves for Regions 4a, 5, and 6, showing that there are very few differences in the relation between drainage area and

  12. Scour and fill in a stream channel, East Fork River, western Wyoming

    USGS Publications Warehouse

    Andrews, Edmund D.

    1978-01-01

    Frequent soundings of 11 cross sections located on the East Fork River, western Wyoming, during a spring flood revealed two sequences of channel scour and fill. All sections either scoured or filled at the flood crests relative to their low-flow condition. The sections which scoured at high flow (called scouring sections) generally tended to fill at low flow. Conversely, the sections which filled at high flow (called filling sections) generally tended to scour at low flow. The critical discharge at which the character of a section changed from scouring to filling or vice versa was approximately the bankfull discharge. Therefore, at any discharge except bankfull, some sections were accumulating bed material (fill), while others were being depleted of bed material (scour). (Woodard-USGS)

  13. Channel adjustment of an unstable coarse-grained stream: Opposing trends of boundary and critical shear stress, and the applicability of extremal hypotheses

    USGS Publications Warehouse

    Simon, A.; Thorne, C.R.

    1996-01-01

    Channel adjustments in the North Fork Toutle River and the Toutle River main stem were initiated by deposition of a 2.5km3 debris avalanche and associated lahars that accompanied the catastrophic eruption of Mount St. Helens, Washington on 18 May 1980. Channel widening was the dominant process. In combination, adjustments caused average boundary shear stress to decrease non-linearly with time and critical shear stress to increase non-linearly with time. At the discharge that is equalled or exceeded 1 per cent of the time, these trends converged by 1991-1992 so that excess shear stress approached minimum values. Extremal hypotheses, such as minimization of unit stream power and minimization of the rate of energy dissipation (minimum stream power), are shown to be applicable to dynamic adjustments of the Toutle River system. Maximization of the Darcy-Weisbach friction factor did not occur, but increases in relative bed roughness, caused by the concomitant reduction in hydraulic depths and bed-material coarsening, were documented. Predictions of stable channel geometries using the minimum stream power approach were unsuccessful when compared to the 1991-1992 geometries and bed-material characteristics measured in the field. It is concluded that the predictions are not applicable because the study reaches are not truly stable and cannot become so until a new floodplain has been formed by renewed channel incision, retreat of stream-side hummocks, and establishment of riparian vegetation to limit the destabilizing effects of large floods. Further, prediction of energy slope (and consequently stream power) by the sediment transport equations is inaccurate because of the inability of the equations to account for significant contributions of finer grained (sand and gravel) bank materials (relative to the coarsened channel bed) from bank retreat and from upstream terrace erosion.

  14. Coronal electron stream and Langmuir wave detection inside a propagation channel at 4.3 AU

    NASA Technical Reports Server (NTRS)

    Buttighoffer, A.; Pick, M.; Roelof, E. C.; Hoang, S.; Mangeney, A.; Lanzerotti, L. J.; Forsyth, R. J.; Phillips, J. L.

    1995-01-01

    Observations of an energetic interplanetary electron event associated with the production of Langmuir waves, both of which are identified at 4.3 AU by instruments on the Ulysses spacecraft, are presented in this paper. This electron event propagates inside a well-defined magnetic structure. The existence of this structure is firmly established by joint particle and plasma observations made by Ulysses instruments. Its local estimated radial width is of the order of 2.3 x 10(exp 7) km (0.15 AU). The electron beam is associated with a type III burst observed from Earth at high frequencies and at low frequencies from Ulysses in association with Langmuir waves detected inside the structure. The consistency of local (Ulysses) and remote (Earth) observations in terms of temporal and geometrical considerations establishes that the structure is anchored in the solar corona near the solar active region responisble for the observed type III emission and gives an accurate determination of the injection time for the observed electron beam. Propagation analysis of the electron event is presented. In order to quantify the magnetic field properties, a variance analysis has been performed and is presented in this paper. The analysis establishes that inside the structure the amount of magnetic energy involved in the fluctuations is less than 4% of the total magnetic energy; the minimal variance direction is well defined and in coincidence with the direction of the mean magnetic field. This configuration may produce conditions favorable for scatter free streaming of energetic electrons and/or Langmuir wave production. The results presented show that the magnetic field might play a role in stabilizing the coronal-origin plasma structures and then preserving them to large, approximately 4 AU, distances in the heliosphere.

  15. Detecting channel riparian vegetation response to best-management-practices implementation in ephemeral streams with the use of spot high-resolution visible imagery

    USGS Publications Warehouse

    Kamp, Kendall Vande; Rigge, Matthew B.; Troelstrup, Nels H.; Smart, Alexander J.; Wylie, Bruce

    2013-01-01

    Heavily grazed riparian areas are commonly subject to channel incision, a lower water table, and reduced vegetation, resulting in sediment delivery above normal regimes. Riparian and in-channel vegetation functions as a roughness element and dissipates flow energy, maintaining stable channel geometry. Ash Creek, a tributary of the Bad River in western South Dakota contains a high proportion of incised channels, remnants of historically high grazing pressure. Best management practices (BMP), including off-stream watering sources and cross fencing, were implemented throughout the Bad River watershed during an Environmental Protection Agency (EPA) 319 effort to address high sediment loads. We monitored prairie cordgrass (Spartina pectinata Link) establishment within stream channels for 16 yr following BMP implementation. Photos were used to group stream reaches (n = 103) subjectively into three classes; absent (estimated  40% cover; n = 16) based on the relative amount of prairie cordgrass during 2010 assessments of ephemeral channels. Reaches containing drainage areas of 0.54 to 692 ha were delineated with the use of 2010 National Agriculture Imagery Program (NAIP) imagery. Normalized difference vegetation index (NDVI) values were extracted from 5 to 39 sample points proportional to reach length using a series of Satellite Pour l'Observation de la Terre (SPOT) satellite imagery. Normalized NDVI (nNDVI) of 2 152 sample points were determined from pre- and post-BMP images. Mean nNDVI values for each reach ranged from 0.33 to 1.77. ANOVA revealed significant increase in nNDVI in locations classified as present prairie cordgrass cover following BMP implementation. Establishment of prairie cordgrass following BMP implementation was successfully detected remotely. Riparian vegetation such as prairie cordgrass adds channel roughness that reduces the flow energy responsible for channel degradation.

  16. Post-Eruption Changes in Channel Geometry of Streams in the Toutle River Drainage Basin, 1980-82, Mount St. Helens, Washington

    USGS Publications Warehouse

    Meyer, D.F.; Nolan, K. Michael; Dodge, J.E.

    1985-01-01

    The May 18, 1980, eruption of Mount St. Helens, Washington, generated a debris avalanche, lateral blast, lahars, and tephra deposits that altered mainstem and tributary channels within the Toutle River drainage basin. Channel cross sections were monumented and surveyed on North Fork Toutle River and its tributaries, on South Fork Toutle River, on Green River, and on Toutle River in 1980 and 1981. These streams drain the north and west flanks of the volcano. The network of channel cross sections was surveyed more frequently following periods of higher flow. The repetitive cross-section surveys provide measurements of bank erosion or accretion and of channel erosion or aggradation. These data can be used to determine erosion rates, and to identify sources and storage sites of sediment in sediment budget computations. This report presents channel cross-section profiles constructed from the survey data collected during water years 1980 through 1982.

  17. Is in-stream macrophyte growth predictable and what are its impacts on channel-averaged flow characteristics?

    NASA Astrophysics Data System (ADS)

    Jordan, David N.; Thomas, Robert E.; Keevil, Gareth M.; Parsons, Daniel R.; Hardy, Richard J.

    2016-04-01

    Understanding how the growth of aquatic vegetation impacts stage-discharge coupling is vital for river management planning. This study presents an annual record of monthly spatial distribution surveys of the in-stream macrophyte Ranunculus penicillatus coupled with channel form and flow velocity measurements, within a 50 m-long reach of a gravel-bed river. Whereas stage has varied by up to 0.4 m, there has been little change in channel form over the monitoring period (ongoing since 23/07/2014). Macrophyte growth continued from the start of the monitoring period until October 2014 when mean patch area was 6.74 m2, and then decreased throughout a decay phase until January 2015 when mean patch area was 1.12 m2. There was a 75.2% loss of macrophyte surface area between October 2014 and January 2015. The largest patches that remained in January 2015 continued to decay until February. Conversely, new macrophyte patches also began to recolonize the channel during this time. To our knowledge, this is the first evidence of a transition period during which aquatic vegetation is in both decay and recolonization phases simultaneously. In total 69% of patches present in January exhibited regrowth without further decay to form a base for recolonization. Therefore, the spatial distribution of macrophyte patches could be determined to be somewhat persistent. Despite this, due to several different growth factors, there are recognisable differences in both macrophyte patch shape and distribution when comparing data from July 2014 and July 2015, emphasising the unpredictability of macrophyte growth. The decay period of the Ranunculus p. coincided with seasonal high discharges in this catchment. Discharge remained high from January until March 2015, but then began to decrease, reflecting annual peaks in historical records for the study area. Large discharge variations were not matched by a large stage range. Displacement of water by vegetation growth maintained the stage height when

  18. Performance of an open limestone channel for treating a stream affected by acid rock drainage (León, Spain).

    PubMed

    Santofimia, Esther; López-Pamo, Enrique

    2016-07-01

    The generation of acid rock drainage (ARD) was observed after the oxidation dissolution of pyrite-rich black shales, which were excavated during the construction of a highway in León (Spain). ARDs are characterized by the presence of high concentrations of sulfate and metals (Al, Fe, Mn, Zn, Cu, Co, Ni, Th, and U) that affect the La Silva stream. Dissolved element concentrations showed values between one and four orders of magnitude higher than those of natural waters of this area. A passive treatment system was constructed; the aim of which was to improve the quality of the water of the stream. This work provides a hydrochemical characterization of the La Silva stream after its transit through the different elements that constitute the passive treatment system (open limestone channel (OLC), small ponds, and a wetland), during its first year of operation. The passive treatment system has two sections separated by a tunnel 230 m long. The first section, which stretches between the highway and the tunnel entrance, is an OLC 350 m long with a slope of 16 %. The second section, which stretches from the tunnel exit to the end wetland, has a length of 700 m and a slope of 6 %; it is in this section where six small ponds are located. In the first section of this passive treatment system, the OLC was effectively increasing the pH from 3 to 4-4.5 and eliminating all of the dissolved Fe and the partially dissolved Al. These elements, after hydrolysis at a pH 3-3.5 and 4-4.5, respectively, had precipitated as schwertmannite and hydrobasaluminite, while other dissolved metals were removed totally or partially for adsorption by the precipitates and/or by coprecipitation. The second section receives different inputs of water such as ARDs and natural waters. After exiting the treatment system, the stream is buffered by Al at a pH of 4-4.3, showing high Al concentrations (19-101 mg/L) but with a complete removal of dissolved Fe. Unfortunately, the outflow shows similar or

  19. Performance of an open limestone channel for treating a stream affected by acid rock drainage (León, Spain).

    PubMed

    Santofimia, Esther; López-Pamo, Enrique

    2016-07-01

    The generation of acid rock drainage (ARD) was observed after the oxidation dissolution of pyrite-rich black shales, which were excavated during the construction of a highway in León (Spain). ARDs are characterized by the presence of high concentrations of sulfate and metals (Al, Fe, Mn, Zn, Cu, Co, Ni, Th, and U) that affect the La Silva stream. Dissolved element concentrations showed values between one and four orders of magnitude higher than those of natural waters of this area. A passive treatment system was constructed; the aim of which was to improve the quality of the water of the stream. This work provides a hydrochemical characterization of the La Silva stream after its transit through the different elements that constitute the passive treatment system (open limestone channel (OLC), small ponds, and a wetland), during its first year of operation. The passive treatment system has two sections separated by a tunnel 230 m long. The first section, which stretches between the highway and the tunnel entrance, is an OLC 350 m long with a slope of 16 %. The second section, which stretches from the tunnel exit to the end wetland, has a length of 700 m and a slope of 6 %; it is in this section where six small ponds are located. In the first section of this passive treatment system, the OLC was effectively increasing the pH from 3 to 4-4.5 and eliminating all of the dissolved Fe and the partially dissolved Al. These elements, after hydrolysis at a pH 3-3.5 and 4-4.5, respectively, had precipitated as schwertmannite and hydrobasaluminite, while other dissolved metals were removed totally or partially for adsorption by the precipitates and/or by coprecipitation. The second section receives different inputs of water such as ARDs and natural waters. After exiting the treatment system, the stream is buffered by Al at a pH of 4-4.3, showing high Al concentrations (19-101 mg/L) but with a complete removal of dissolved Fe. Unfortunately, the outflow shows similar or

  20. MWSA's physical habitat approach - combining knowledge of habitat requirements with mechanisms of geomorphic and anthropogenic influence on stream channel form

    EPA Science Inventory

    Effective environmental policy decisions benefit from stream habitat information that is accurate, precise, and relevant. The recent National Wadeable Streams Assessment (NWSA) carried out by the U.S. EPA required physical habitat information sufficiently comprehensive to facilit...

  1. Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio

    USGS Publications Warehouse

    Sherwood, James M.; Huitger, Carrie A.; Ebner, Andrew D.; Koltun, G.F.

    2008-01-01

    The USGS, in cooperation with the Ohio Emergency Management Agency, conducted a study in the Wheeling Creek Basin to (1) evaluate and contrast land-cover characteristics from 2001 with characteristics from 1979 and 1992; (2) compare current streambed elevation, slope, and geometry with conditions present in the late 1980s; (3) look for evidence of channel filling and over widening in selected undredged reaches; (4) estimate flood elevations for existing conditions in both undredged and previously dredged reaches; (5) evaluate the height of the levees required to contain floods with selected recurrence intervals in previously dredged reaches; and (6) estimate flood elevations for several hypothetical dredging and streambed aggradation scenarios in undredged reaches. The amount of barren land in the Wheeling Creek watershed has decreased from 20 to 1 percent of the basin area based on land-cover characteristics from 1979 and 2001. Barren lands appear to have been converted primarily to pasture, presumably as a result of surface-mine reclamation. Croplands also decreased from 13 to 8 percent of the basin area. The combined decrease in barren lands and croplands is approximately offset by the increase in pasture. Stream-channel surveys conducted in 1987 and again in 2006 at 21 sites in four previously dredged reaches of Wheeling Creek indicate little change in the elevation, slope, and geometry of the channel at most sites. The mean change in width-averaged bed and thalweg elevations for the 21 cross sections was 0.1 feet. Bankfull widths, mean depths, and cross-sectional areas measured at 12 sites in undredged reaches were compared to estimates determined from regional equations. The mean percentage difference between measured and estimated bankfull widths was -0.2 percent, suggesting that bankfull widths in the Wheeling Creek Basin are generally about the same as regional averages for undisturbed basins of identical drainage area. For bankfull mean depth and cross

  2. Mode couplings in a two-stream free-electron laser with a helical wiggler and an ion-channel guiding

    SciTech Connect

    Mohsenpour, Taghi Alirezaee, Hajar

    2014-08-15

    In this study, the method of perturbation has been applied to obtain the dispersion relation (DR) of a two-stream free-electron laser (FEL) with a helical wiggler and an ion-channel with all relativistic effects on waves. This DR has been solved numerically to find the unstable modes and their growth rate. Numerical solutions of DR show that the growth rate is considerably enhanced in comparison with single-stream free-electron laser. In group II orbits, with relatively large wiggler induced velocities, new couplings are found. The effect of the velocity difference of the two electron beams on the instabilities has also been investigated in this study. Moreover, the effect of the ion-channel density on the maximum growth rate of FEL resonance has been analyzed.

  3. Abandoned Texas oil fields

    SciTech Connect

    Not Available

    1980-12-01

    Data for Texas abandoned oil fields were primarily derived from two sources: (1) Texas Railroad Commission (TRRC), and (2) Dwight's ENERGYDATA. For purposes of this report, abandoned oil fields are defined as those fields that had no production during 1977. The TRRC OILMASTER computer tapes were used to identify these abandoned oil fields. The tapes also provided data on formation depth, gravity of oil production, location (both district and county), discovery date, and the cumulative production of the field since its discovery. In all, the computer tapes identified 9211 abandoned fields, most of which had less than 250,000 barrel cumulative production. This report focuses on the 676 abandoned onshore Texas oil fields that had cumulative production of over 250,000 barrels. The Dwight's ENERGYDATA computer tapes provided production histories for approximately two-thirds of the larger fields abandoned in 1966 and thereafter. Fields which ceased production prior to 1966 will show no production history nor abandonment date in this report. The Department of Energy hopes the general availability of these data will catalyze the private sector recovery of this unproduced resource.

  4. Water quality, sediment quality, and stream-channel classification of Rock Creek, Washington, D.C., 1999-2000

    USGS Publications Warehouse

    Anderson, Anita L.; Miller, Cherie V.; Olsen, Lisa D.; Doheny, Edward J.; Phelan, Daniel J.

    2002-01-01

    Rock Creek Park is within the National Capital Region in Washington, D.C., and is maintained by the National Park Service. Part of Montgomery County, Maryland, and part of the District of Columbia drain into Rock Creek, which is a tributary of the Potomac River. Water quality in Rock Creek is important to biotic life in and near the creek, and in the Potomac River Basin and the Chesapeake Bay. The water quality of the Rock Creek Basin has been affected by continued urban and agricultural growth and development. The U.S. Geological Survey, in cooperation with the National Park Service, investigated water quality and sediment quality in Rock Creek over a 2-year period (1998?2000), and performed a stream-channel classification to determine the distribution of bottom sediment in Rock Creek. This report presents and evaluates water quality and bottom sediment in Rock Creek for water years 1999 (October 1, 1998 to September 30, 1999) and 2000 (October 1, 1999 to September 30, 2000). A synoptic surface-water assessment was conducted at five stations from June 23 to June 25, 1999, a temporal surface-water assessment was conducted at one station from February 18, 1999 to September 26, 2000, and bed-sediment samples were collected and assessed from three stations from August 17 to August 19, 1999. The synoptic surface-water assessment included pesticides (parent compounds and selected transformation products), field parameters, nutrients, and major ions. The temporal surface-water assessment included pesticides (parent compounds and selected transformation products) and field parameters. The bed-sediment assessment included trace elements and organic compounds (including low- and high-molecular weight polycyclic aromatic hydrocarbons, poly-chlorinated biphenyls, pesticides, and phthalates). Some, but not all, of the pesticides known to be used in the area were included in the synoptic water-quality assessment, the temporal water-quality assessment, and the bed

  5. Immediate changes in stream channel geomorphology, aquatic habitat, and fish assemblages following dam removal in a small upland catchment

    NASA Astrophysics Data System (ADS)

    Magilligan, F. J.; Nislow, K. H.; Kynard, B. E.; Hackman, A. M.

    2016-01-01

    Dam removal is becoming an increasingly important component of river restoration, with > 1100 dams having been removed nationwide over the past three decades. Despite this recent progression of removals, the lack of pre- to post-removal monitoring and assessment limits our understanding of the magnitude, rate, and sequence of geomorphic and/or ecological recovery to dam removal. Taking advantage of the November 2012 removal of an old (~ 190 year-old) 6-m high, run-of-river industrial dam on Amethyst Brook (26 km2) in central Massachusetts, we identify the immediate eco-geomorphic responses to removal. To capture the geomorphic responses to dam removal, we collected baseline data at multiple scales, both upstream (~ 300 m) and downstream (> 750 m) of the dam, including monumented cross sections, detailed channel-bed longitudinal profiles, embeddedness surveys, and channel-bed grain size measurements, which were repeated during the summer of 2013. These geomorphic assessments were combined with detailed quantitative electrofishing surveys of stream fish richness and abundance above and below the dam site and throughout the watershed and visual surveys of native anadromous sea lamprey (Petromyzon marinus) nest sites. Post-removal assessments were complicated by two events: (1) upstream knickpoint migration exhumed an older (ca. late eighteenth century) intact wooden crib dam ~ 120 m upstream of the former stone dam, and (2) the occurrence of a 10-20 year RI flood 6 months after removal that caused further upstream incision and downstream aggradation. Now that the downstream reach has been reconnected to upstream sediment supply, the predominant geomorphic response was bed aggradation and associated fining (30-60% reduction). At dam proximal locations, aggradation ranged from 0.3 to > 1 m where a large woody debris jam enhanced aggradation. Although less pronounced, distal locations still showed aggradation with a mean depth of deposition of ~ 0.20 m over the 750-m

  6. Preliminary characterization of abandoned septic tank systems. Volume 1

    SciTech Connect

    1995-12-01

    This report documents the activities and findings of the Phase I Preliminary Characterization of Abandoned Septic Tank Systems. The purpose of the preliminary characterization activity was to investigate the Tiger Team abandoned septic systems (tanks and associated leachfields) for the purpose of identifying waste streams for closure at a later date. The work performed was not to fully characterize or remediate the sites. The abandoned systems potentially received wastes or effluent from buildings which could have discharged non-domestic, petroleum hydrocarbons, hazardous, radioactive and/or mixed wastes. A total of 20 sites were investigated for the preliminary characterization of identified abandoned septic systems. Of the 20 sites, 19 were located and characterized through samples collected from each tank(s) and, where applicable, associated leachfields. The abandoned septic tank systems are located in Areas 5, 12, 15, 25, and 26 on the Nevada Test Site.

  7. Abandoning wells working group

    SciTech Connect

    1997-03-01

    The primary objective of this working group is to identify major technical, regulatory, and environmental issues that are relevant to the abandonment of offshore wellbores. Once the issues have been identified, the working group also has the objective of making recommendations or providing potential solutions for consideration. Areas for process improvement will be identified and {open_quotes}best practices{close_quotes} will be discussed and compared to {open_quotes}minimum standards.{close_quotes} The working group will primarily focus on wellbore abandonment in the Gulf of Mexico. However, workshop participants are encouraged to discuss international issues which may be relevant to wellbore abandonment practices in the Gulf of Mexico. The Abandoning Wells Group has identified several major areas for discussion that have concerns related to both operators and service companies performing wellbore abandonments in the Gulf of Mexico. The following broad topics were selected for the agenda: (1) MMS minimum requirements and state regulations. (2) Co-existence of best practices, new technology, and P & A economics. (3) Liability and environmental issues relating to wellbore abandonment.

  8. Acoustic signal propagation and measurement in natural stream channels for application to surrogate bed load measurements: Halfmoon Creek, Colorado

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Monitoring sediment-generated noise using submerged hydrophones is a surrogate method for measuring bed load transport in streams with the potential for improving estimates of bed load transport through widespread, inexpensive monitoring. Understanding acoustic signal propagation in natural stream e...

  9. Ephemeral-Stream Channel and Basin-Floor Infiltration and Recharge in the Sierra Vista Subwatershed of the Upper San Pedro Basin, Southeastern Arizona

    USGS Publications Warehouse

    Coes, A.L.; Pool, D.R.

    2007-01-01

    The timing and location of streamflow in the San Pedro River are partially dependent on the aerial distribution of recharge in the Sierra Vista subwatershed. Previous investigators have assumed that recharge in the subwatershed occurs only along the mountain fronts by way of stream-channel infiltration near the contact between low-permeability rocks of the mountains and the basin fill. Recent studies in other alluvial basins of the Southwestern United States, however, have shown that significant recharge can occur through the sediments of ephemeral stream channels at locations several kilometers distant from the mountains. The purpose of this study was to characterize the spatial distribution of infiltration and subsequent recharge through the ephemeral channels in the Sierra Vista subwatershed. Infiltration fluxes in ephemeral channels and through the basin floor of the subwatershed were estimated by using several methods. Data collected during the drilling and coring of 16 boreholes included physical, thermal, and hydraulic properties of sediments; chloride concentrations of sediments; and pore-water stable-isotope values and tritium activity. Surface and subsurface sediment temperatures were continuously measured at each borehole. Twelve boreholes were drilled in five ephemeral stream channels to estimate infiltration within ephemeral channels. Active infiltration was verified to at least 20 meters at 11 of the 12 borehole sites on the basis of low sediment-chloride concentrations, high soil-water contents, and pore-water tritium activity similar to present-day precipitation. Consolidated sediments at the twelfth site prevented core recovery and estimation of infiltration. Analytical and numerical methods were applied to determine the surface infiltration flux required to produce the observed sediment-temperature fluctuations at six sites. Infiltration fluxes were determined for summer ephemeral flow events only because no winter flows were recorded at the sites

  10. Meta-Analysis of Lost Ecosystem Attributes in Urban Streams and the Effectiveness of Out-of-Channel Management Practices

    EPA Science Inventory

    Watershed development is a leading cause of stream impairment, and it increasingly threatens the availability, quality, and sustainability of freshwater resources as human populations continue to grow and migrate. Most efforts have focused on trying to improve ecological conditio...

  11. Suspended-sediment yields and stream-channel processes on Judy's Branch watershed in the St. Louis Metro East region in Illinois

    USGS Publications Warehouse

    Straub, Timothy D.; Johnson, Gary P.; Roseboom, Donald P.; Sierra, Carlos R.

    2006-01-01

    Judy's Branch watershed, a small basin (8.64 square miles) in the St. Louis Metro East region in Illinois, was selected as a pilot site to determine suspended-sediment yields and stream-channel processes in the bluffs and American Bottoms (expansive low-lying valley floor in the region). Suspended-sediment and stream-chan-nel data collected and analyzed for Judy's Branch watershed are presented in this report to establish a baseline of data for water-resource managers to evaluate future stream rehabilitation and manage-ment alternatives. The sediment yield analysis determines the amount of sediment being delivered from the watershed and two subwatersheds: an urban tributary and an undeveloped headwater (pri-marily agricultural). The analysis of the subwater-sheds is used to compare the effects of urbanization on sediment yield to the river. The stream-channel contribution to sediment yield was determined by evaluation of the stream-channel processes operat-ing on the streambed and banks of Judy's Branch watershed. Bank stability was related to hydrologic events, bank stratigraphy, and channel geometry through model development and simulation. The average suspended-sediment yield from two upland subwatersheds (drainage areas of 0.23 and 0.40 sq.mi. was 1,163 tons per square mile per year (tons/sq.mi.-year) between July 2000 and June 2004. The suspended-sediment yield at the Route 157 station was 2,523 tons/sq.mi.-year, near the outlet of Judy's Branch watershed (drainage area = 8.33 sq.mi.). This is approximately 1,360 tons/sq.mi.-year greater than the average at the upland stations for the same time period. This result is unexpected in that, generally, the suspended-sediment yield decreases as the watershed area increases because of sediment stored in the channel and flood plain. The difference indicates a possible increase in yield from a source, such as bank retreat, and supports the concept that land-use changes increase stream-flows that may in turn result in

  12. Near-Channel Sources and Sinks along a Mountainous Stream: Establishing the Controls and Time Scales of the Lateral Transfer of Sediment and Carbon

    NASA Astrophysics Data System (ADS)

    Gartner, J. D.; Renshaw, C. E.

    2015-12-01

    River channels exchange sediment, carbon, and other matter with hillslopes and floodplains. An ongoing challenge is to quantify the time and length scales of these lateral interactions, and to establish physical controls on direction of transfer. Here we investigate whether downstream changes in stream power (Ω) can predict near-channel sources or sinks of matter on decadal time scales in a case study of Mink Brook, a 50 km2 watershed in New Hampshire, USA. Building on the Exner equation, we hypothesize that reaches with downstream increases in stream power (Ω↑) exhibit near-channel deposition and accumulation of organic matter, and reaches of downstream decreases in stream power (Ω↓) exhibit near-channel erosion and stripping of organic matter. We measured 210Pbex inventory (an indicator of erosion versus deposition), organic matter inventory, grain size, and depth of alluvium/colluvium in 29 soil pits at 6 cross sections along the brook. Sites had equivalent total Ω for a given storm event. However, 3 cross sections exhibited Ω↑, and 3 exhibited Ω↓. All cross sections showed a general trend of stripping of organic matter and fine sediment particles in the channel, paired with loading of matter at the ~2-year flood elevation. From the ~2- to ~25-year flood elevation, a marked difference appeared between sites. The Ω↑ cross sections exhibited several locations of erosion and stripping of organic matter, as evidenced by low 210Pbex inventories (70 to 1,000 bq m-2), low organic matter inventories (17 to 219 kg m-2), and thin alluvial cover (average 23 cm). The low 210Pbex inventories, below the characteristic 6,000 bq m-2 of stable soil profiles in this region, suggest no areas had consistent deposition over the last century. In contrast, the Ω↓ cross sections exhibited deposition of fine particles and organic matter from the ~2- to ~25-year flood elevation, as evidenced by elevated 210Pbex inventories (up to 9,100 bq m-2), elevated organic matter

  13. Influence of adding small instream wood on fishes and hydrology within channelized agricultural headwater streams in central Ohio

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Large instream wood is well known for its importance in headwater streams because it promotes the development of pool habitat for fishes and provides them with cover from predators during the summer. However, little is known about the influence of small instream wood (diameter < 10 cm, length < 1 m...

  14. CHNTRN: a CHaNnel TRaNsport model for simulating sediment and chemical distribution in a stream/river network

    SciTech Connect

    Yeh, G.T.

    1983-09-01

    This report presents the development of a CHaNnel TRaNsport model for simulating sediment and chemical distribution in a stream/river network. A particular feature of the model is its capability to deal with the network system that may consist of any number of joined and branched streams/rivers of comparable size. The model employs a numerical method - an integrated compartment method (ICM) - which greatly facilitates the setup of the matrix equation for the discrete field approximating the corresponding continuous field. Most of the possible boundary conditions that may be anticipated in real-world problems are considered. These include junctions, prescribed concentration, prescribed dispersive flux, and prescribed total flux. The model is applied to two case studies: (1) a single river and (2) a five-segment river in a watershed. Results indicate that the model can realistically simulate the behavior of the sediment and chemical variations in a stream/river network. 11 references, 10 figures, 3 tables.

  15. Channel

    NASA Technical Reports Server (NTRS)

    2006-01-01

    [figure removed for brevity, see original site] Context image for PIA03693 Channel

    This channel is located south of Iani Chaos.

    Image information: VIS instrument. Latitude -10.9N, Longitude 345.5E. 17 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  16. Salmon carcasses increase stream productivity more than inorganic fertilizer pellets: A test on multiple trophic levels in streamside experimental channels

    USGS Publications Warehouse

    Wipfli, Mark S.; Hudson, John P.; Caouette, John P.; Mitchell, N.L.; Lessard, Joanna L.; Heintz, Ron A.; Chaloner, D.T.

    2010-01-01

    Inorganic nutrient amendments to streams are viewed as possible restoration strategies for re-establishing nutrients and stream productivity throughout the western coast of North America, where salmon runs and associated marine-derived nutrient subsidies have declined. In a mesocosm experiment, we examined the short-term (6 weeks) comparative effects of artificial nutrient pellets and salmon carcasses, alone (low and high amounts) and in combination, on stream food webs. Response variables included dissolved nutrient concentrations, biofilm ash-free dry mass (AFDM) and chlorophyll-alevels, macroinvertebrate density, growth and body condition of juvenile coho salmon Oncorhynchus kisutch, and whole-body lipid content of invertebrates and juvenile coho salmon. Most of the response variables were significantly influenced by carcass treatment; the only response variable significantly influenced by fertilizer pellet treatment was soluble reactive phosphorus (SRP) concentration. Ammonium-nitrogen concentration was the only response variable affected by both (low and high) levels of carcass treatment; all others showed no significant response to the two carcass treatment levels. Significant treatment × time interactions were observed for all responses except nitrate; for most responses, significant treatment effects were detected at certain time periods and not others. For example, significantly higher SRP concentrations were recorded earlier in the experiment, whereas significant fish responses were observed later. These results provide evidence that inorganic nutrient additions do not have the same ecological effects in streams as do salmon carcasses, potentially because inorganic nutrient additions lack carbon-based biochemicals and macromolecules that are sequestered directly or indirectly by consumers. Salmon carcasses, preferably deposited naturally during spawning migrations, appear to be far superior to inorganic nutrient amendments for sustaining and restoring

  17. Field Observations of Supraglacial Streams on the Juneau Icefield

    NASA Astrophysics Data System (ADS)

    Zok, A.; Karlstrom, L.; Hood, E. W.; Manga, M.; Wenzel, R.; Kite, E. S.

    2010-12-01

    of frictional heat dissipation to this heating trend. Cross-sectional water velocity profiles show that most streams have very low bed friction and are affected strongly by the free surface, resulting in large deviations from logarithmic velocity profiles. Measured changes of the water table depth in porous ice allow the permeability of ice to be quantified. It appears that rapid channel formation and abandonment near the neve line occurs via seepage. We observe large differences in hydrogen and oxygen isotopes in water from the two sites, and between ice, rainwater, and streams of different sizes within each site. The sinuosity of supraglacial streams is correlated with local slope, and we find supraglacial stream meanders to follow the linear wavelength-width relation also seen in alluvial and bedrock channels, with a smaller intercept. These measurements of meander characteristics are in accord with a linear stability analysis of supraglacial meander formation.

  18. Modeling Tidal Stream Energy Extraction and its Effects on Transport Processes in a Tidal Channel and Bay System Using a Three-dimensional Coastal Ocean Model

    SciTech Connect

    Yang, Zhaoqing; Wang, Taiping; Copping, Andrea E.

    2013-02-28

    This paper presents a numerical modeling study for simulating in-stream tidal energy extraction and assessing its effects on the hydrodynamics and transport processes in a tidal channel and bay system connecting to coastal ocean. A marine and hydrokinetic (MHK) module was implemented in a three-dimensional (3-D) coastal ocean model using the momentum sink approach. The MHK model was validated with the analytical solutions for tidal channels under one-dimensional (1-D) conditions. Model simulations were further carried out to compare the momentum sink approach with the quadratic bottom friction approach. The effects of 3-D simulations on the vertical velocity profile, maximum extractable energy, and volume flux reduction across the channel were investigated through a series of numerical experiments. 3-D model results indicate that the volume flux reduction at the maximum extractable power predicted by the 1-D analytical model or two-dimensional (2-D) depth-averaged numerical model may be overestimated. Maximum extractable energy strongly depends on the turbine hub height in the water column, and which reaches a maximum when turbine hub height is located at mid-water depth. Far-field effects of tidal turbines on the flushing time of the tidal bay were also investigated. Model results demonstrate that tidal energy extraction has a greater effect on the flushing time than volume flux reduction, which could negatively affect the biogeochemical processes in estuarine and coastal waters that support primary productivity and higher forms of marine life.

  19. Development of regional curves relating bankfull-channel geometry and discharge to drainage area for streams in Pennsylvania and selected areas of Maryland

    USGS Publications Warehouse

    Chaplin, Jeffrey J.

    2005-01-01

    Natural-stream designs are commonly based on the dimensions of the bankfull channel, which is capable of conveying discharges that transport sediment without excessive erosion or deposition. Regional curves relate bankfull-channel geometry and discharge to drainage area in watersheds with similar runoff characteristics and commonly are utilized by practitioners of natural-stream design to confirm or refute selection of the field-identified bankfull channel. Data collected from 66 streamflow-gaging stations and associated stream reaches between December 1999 and December 2003 were used in one-variable ordinary least-squares regression analyses to develop regional curves relating drainage area to cross-sectional area, discharge, width, and mean depth of the bankfull channel. Watersheds draining to these stations are predominantly within the Piedmont, Ridge and Valley, and Appalachian Plateaus Physiographic Provinces of Pennsylvania and northern Maryland. Statistical analyses of physiography, percentage of watershed area underlain by carbonate bedrock, and percentage of watershed area that is glaciated indicate that carbonate bedrock, not physiography or glaciation, has a controlling influence on the slope of regional curves. Regional curves developed from stations in watersheds underlain by 30 percent or less carbonate bedrock generally had steeper slopes than the corresponding relations developed from watersheds underlain by greater than 30 percent carbonate bedrock. In contrast, there is little evidence to suggest that regional curves developed from stations in the Piedmont or Ridge and Valley Physiographic Province are different from the corresponding relations developed from stations in the Appalachian Plateaus Physiographic Province. On the basis of these findings, regional curves are presented to represent two settings that are independent of physiography: (1) noncarbonate settings characterized by watersheds with carbonate bedrock underlying 30 percent or less

  20. Effects of streamflows on stream-channel morphology in the eastern Niobrara National Scenic River, Nebraska, 1988–2010

    USGS Publications Warehouse

    Schaepe, Nathaniel J.; Alexander, Jason S.; Folz-Donahue, Kiernan

    2016-03-09

    Large changes were measured between 1993 and 1999, and between 1999 and 2003, at many of the fixed-location cross sections. Large changes (that is, greater than 25 percent) in total channel width were measured in all three segments between 1993 and 1999 and again between 1999 and 2003; large increases were dominant between 199

  1. Abandoned floodplain plant communities along a regulated dryland river

    USGS Publications Warehouse

    Reynolds, L. V.; Shafroth, Patrick B.; House, P. K.

    2014-01-01

    Rivers and their floodplains worldwide have changed dramatically over the last century because of regulation by dams, flow diversions and channel stabilization. Floodplains no longer inundated by river flows following dam-induced flood reduction comprise large areas of bottomland habitat, but the effects of abandonment on plant communities are not well understood. Using a hydraulic flow model, geomorphic mapping and field surveys, we addressed the following questions along the Bill Williams River, Arizona: (i) What per cent of the bottomland do abandoned floodplains comprise? and (ii) Are abandoned floodplains quantitatively different from adjacent xeric and riparian surfaces in terms of vegetation composition and surface sediment? We found that nearly 70% of active channel and floodplain area was abandoned following dam installation. Abandoned floodplains along the Bill Williams River tend to be similar to each other yet distinct from neighbouring habitats: they have been altered physically from their historic state, leading to distinct combinations of surface sediments, hydrology and plant communities. Abandoned floodplains may transition to xeric communities over time but are likely to retain some riparian qualities as long as there is access to relatively shallow ground water. With expected increases in water demand and drying climatic conditions in many regions, these surfaces and associated vegetation will continue to be extensive in riparian landscapes worldwide

  2. Rock riprap design for protection of stream channels near highway structures; Volume 2, Evaluation of Riprap design procedures

    USGS Publications Warehouse

    Blodgett, J.C.; McConaughy, C.E.

    1986-01-01

    In volume 2, seven procedures now being used for design of rock riprap installations were evaluated using data from 26 field sites. Four basic types of riprap failures were identified: Particle erosion, translational slide, modified slump, and slump. Factors associated with riprap failure include stone size , bank side slope, size gradation, thickness, insufficient toe or endwall, failure of the bank material, overtopping during floods, and geomorphic changes in the channel. A review of field data and the design procedures suggests that estimates of hydraulic forces acting on the boundary based on flow velocity rather than shear stress are more reliable. Several adjustments for local conditions, such as channel curvature, superelevation, or boundary roughness, may be unwarranted in view of the difficulty in estimating critical hydraulic forces for which the riprap is to be designed. Success of the riprap is related not only to the appropriate procedure for selecting stone size, but also to the reliability of estimated hydraulic and channel factors applicable to the site. (See also W89-04910) (Author 's abstract)

  3. Effects of streamflows on stream-channel morphology in the eastern Niobrara National Scenic River, Nebraska, 1988–2010

    USGS Publications Warehouse

    Schaepe, Nathaniel J.; Alexander, Jason S.; Folz-Donahue, Kiernan

    2016-03-09

    Changes in channel metrics generally corresponded to changes in streamflow conditions, but other than changes in incipient flood-plain area, these changes were small and were not measured in all three segments simultaneously. Increases in total channel width (except in segment 1) and incipient flood-plain area between 1993 and 1999 corresponded to increases in streamflow. Channel narrowing (except in segment 1) between 1999 and 2003 corresponded to lower summer streamflows and extended durations of very low summer streamflow. Although the pattern of low summer streamflow and extended durations of very low summer streamflow continued during the 2004–6 period and at the beginning of the 2007–10 period, no further narrowing was measured. Consistent tributary summer inflows help to explain the resistance of segments 2 and 3 to further narrowing. Because segment 1 is already much narrower than segments 2 and 3, its average current velocity is likely to be swifter and, therefore, competent to offset further effects of the processes that led to its narrowness.

  4. A Modeling Study of In-stream Tidal Energy Extraction and Its Potential Environmental Impacts in a Tidal Channel and Bay System

    NASA Astrophysics Data System (ADS)

    Wang, T.; Yang, Z.; Copping, A. E.

    2012-12-01

    In recent years, there has been growing interest in harnessing in-stream tidal energy in response to concerns of increasing energy demand and to mitigate climate change impacts. While efforts have been made to assess and map available tidal energy resources using numerical models, little attention has been paid directly quantifying the associated potential environmental impacts as part of tidal energy generation. This paper presents the development of a tidal turbine module within a three-dimensional (3-D) unstructured grid coastal ocean model. The model is used to investigate in-stream tidal energy extraction and associated impacts on estuarine hydrodynamic and biological processes in a stratified estuarine system. A series of numerical experiments with varying numbers and configurations of turbines were carried out to assess the changes in the hydrodynamics and biological processes in the tidal channel and bay system due to tidal energy extraction. Model results show the maximum extractable energy depends strongly on the turbine hub height, and that the effects of energy extraction on the flow fields vary vertically. Preliminary model results also indicate that extraction of tidal energy increases vertical mixing and decreases flushing rate in the estuary. As one of the early modeling efforts aimed directly at examining the impacts of tidal energy extraction on estuarine circulation and biological processes, this study demonstrates that numerical models can serve as a very useful tool for this purpose. However, careful efforts are warranted to address system-specific environmental issues in real world, complex estuarine systems.

  5. Offshore abandonment heats up

    SciTech Connect

    1995-08-01

    This paper reviews the new concerns regarding the decommissioning of offshore oil platforms which are rapidly coming of age. It reviews the history of past removal operations and the public outcry which is now causing a reevaluation of this abandonment policy. It reviews the number of platforms which are rapidly approaching maturity on a global basis. It then goes on to costs involved in such removal operations. Finally, it reviews the new platform designs which should allow a much more cost effective decommissioning process for these future rigs.

  6. 37 CFR 1.138 - Express abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Express abandonment. 1.138... Applicant; Abandonment of Application § 1.138 Express abandonment. (a) An application may be expressly abandoned by filing a written declaration of abandonment identifying the application in the United...

  7. 33 CFR 245.45 - Abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Abandonment. 245.45 Section 245... REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.45 Abandonment. (a) Establishing abandonment. Abandonment... owners if vessel and cargo are separately owned. In all cases other than emergency, abandonment will...

  8. 37 CFR 1.138 - Express abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Express abandonment. 1.138... Applicant; Abandonment of Application § 1.138 Express abandonment. (a) An application may be expressly abandoned by filing a written declaration of abandonment identifying the application in the United...

  9. 33 CFR 245.45 - Abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Abandonment. 245.45 Section 245... REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.45 Abandonment. (a) Establishing abandonment. Abandonment... owners if vessel and cargo are separately owned. In all cases other than emergency, abandonment will...

  10. 37 CFR 1.138 - Express abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Express abandonment. 1.138... Applicant; Abandonment of Application § 1.138 Express abandonment. (a) An application may be expressly abandoned by filing a written declaration of abandonment identifying the application in the United...

  11. 37 CFR 1.138 - Express abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Express abandonment. 1.138... Applicant; Abandonment of Application § 1.138 Express abandonment. (a) An application may be expressly abandoned by filing a written declaration of abandonment identifying the application in the United...

  12. 37 CFR 1.138 - Express abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Express abandonment. 1.138... Applicant; Abandonment of Application § 1.138 Express abandonment. (a) An application may be expressly abandoned by filing a written declaration of abandonment identifying the application in the United...

  13. 33 CFR 245.45 - Abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 3 2014-07-01 2014-07-01 false Abandonment. 245.45 Section 245... REMOVAL OF WRECKS AND OTHER OBSTRUCTIONS § 245.45 Abandonment. (a) Establishing abandonment. Abandonment... owners if vessel and cargo are separately owned. In all cases other than emergency, abandonment will...

  14. Glacially-megalineated limestone terrain of Anticosti Island, Gulf of St. Lawrence, Canada; onset zone of the Laurentian Channel Ice Stream

    NASA Astrophysics Data System (ADS)

    Eyles, Nick; Putkinen, Niko

    2014-03-01

    postulated Laurentian Channel Ice Stream (LCIS) within the Gulf of St. Lawrence sector of the Laurentide Ice Sheet.

  15. The Abandonment of Social Studies?

    ERIC Educational Resources Information Center

    Griffith, Bryant

    1991-01-01

    Addresses the question of whether the social studies should be abandoned. Discusses Kieran Egan's analysis of the importance of storytelling and Egan's proposal to abandon the social studies curriculum in favor of a pedagogy more consistent with the way children think. Critiques Egan's view and examines implications for educators. (SG)

  16. Evaluation of irrigation canal networks to assess stream connectivity in a watershed

    USGS Publications Warehouse

    Colvin, M.E.; Moffitt, C.M.

    2009-01-01

    We used digital data sets, aerial photos and direct field observations in a geographical information system to evaluate the stream habitat in an Idaho watershed affected by agriculture. We found that the scale of the digital data sets affected the outcome of the assessment due to the presence of dewatered stream channels in the drainage. We analysed the spatial configuration of irrigation canals in the watershed to determine if the contemporary stream network connectivity could be attributed to human- caused or to natural hydrological processes. Many irrigation canals were significantly longer than would have been expected if these canals were constructed to capture water from the closest portion of the abandoned stream channels. Our findings provide evidence that some of these tributary streams had reaches that were likely ephemeral or intermittent at the time of canal construction. Our approach for assessing stream and irrigation network connectivity in pastoral and agricultural lands should aid managers in prioritizing the effective and appropriate reconnection efforts. Published in 2008 by John Wiley & Sons Ltd. ?? 2008 John Wiley & Sons, Ltd.

  17. Urban Stream Ecology

    EPA Science Inventory

    Urban watersheds characteristically have high impervious surface cover, resulting in high surface runoff and low infiltration following storms. In response, urban streams experience “flashy” stormflows, reduced baseflows, bank erosion, channel widening, and sedimentation. Urban ...

  18. Macroinvertebrate response to stream restoration by large wood addition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Channel incision processes resulting primarily from channel straightening/dredging and watershed deforestation have been among the most profound degradations in our streams. Physical changes to streams affected by channel incision processes have included significant increases in streambed degradatio...

  19. Effects of hatchery fish density on emigration, growth, survival, and predation risk of natural steelhead parr in an experimental stream channel

    USGS Publications Warehouse

    Tatara, Christopher P.; Riley, Stephen C.; Berejikian, Barry A.

    2011-01-01

    Hatchery supplementation of steelhead Oncorhynchus mykiss raises concerns about the impacts on natural populations, including reduced growth and survival, displacement, and increased predation. The potential risks may be density dependent.We examined how hatchery stocking density and the opportunity to emigrate affect the responses of natural steelhead parr in an experimental stream channel and after 15 d found no density-dependent effects on growth, emigration, or survival at densities ranging from 1-6 hatchery parr/m2. The opportunity for steelhead parr to emigrate reduced predation by coastal cutthroat trout O. clarkii clarkii on both hatchery and natural steelhead parr. The cutthroat trout exhibited a type-I functional response (constant predation rate with increased prey density) for the hatchery and composite populations. In contrast, the predation rate on natural parr decreased as hatchery stocking density increased. Supplementation with hatchery parr at any experimental stocking density reduced the final natural parr density. This decline was explained by increased emigration fromthe supplemented groups. Natural parr had higher mean instantaneous growth rates than hatchery parr. The proportion of parr emigrating decreased as parr size increased over successive experimental trials. Smaller parr had lower survival and suffered higher predation. The final density of the composite population, a measure of supplementation effectiveness, increased with the hatchery steelhead stocking rate. Our results indicate that stocking larger hatchery parr (over 50 d postemergence) at densities within the carrying capacity would have low short-term impact on the growth, survival, and emigration of natural parr while increasing the density of the composite population; in addition, a stocking density greater than 3 fish/m2 might be a good starting point for the evaluation of parr stocking in natural streams.

  20. Experimental Tests of Priority Effects and Light Availability on Relative Performance of Myriophyllum spicatum and Elodea nuttallii Propagules in Artificial Stream Channels

    PubMed Central

    Zefferman, Emily P.

    2015-01-01

    Submersed macrophytes have important ecological functions in many streams, but fostering growth of beneficial native species while suppressing weedy invasives may be challenging. Two approaches commonly used in management of terrestrial plant communities may be useful in this context: (1) altering resource availability and (2) establishing desirable species before weeds can invade (priority effects). However, these approaches are rarely used in aquatic systems, despite widespread need for sustainable solutions to aquatic weed problems. In artificial stream channels in California, USA, I conducted experiments with asexual propagules of non-native invasive Myriophyllum spicatum (Eurasian watermilfoil) and native Elodea nuttallii (western waterweed) to address the questions: (1) How does light availability affect relative performance of the two species?; (2) Does planting the native earlier than the invasive decrease survival or growth rate of the invasive?; and (3) Do light level and priority effects interact? The relative performance between E. nuttallii and M. spicatum had an interesting and unexpected pattern: M. spicatum had higher growth rates than E. nuttallii in the zero and medium shade levels, but had similar performance in the low and high shade levels. This pattern is most likely the result of E. nutallii’s sensitivity to both very low and very high light, and M. spicatum’s sensitivity to very low light only. Native priority did not significantly affect growth rate or survival of M. spicatum, possibly because of unexpectedly poor growth of the E. nuttallii planted early. This study suggests that altering light levels could be effective in reducing growth of an invasive macrophyte, and for changing the competitive balance between a native and a non-native species in the establishment phase. Further investigations into the use of priority effects and resource alteration for submersed macrophyte management are warranted, given their mixed results in other

  1. Experimental tests of priority effects and light availability on relative performance of Myriophyllum spicatum and Elodea nuttallii propagules in artificial stream channels.

    PubMed

    Zefferman, Emily P

    2015-01-01

    Submersed macrophytes have important ecological functions in many streams, but fostering growth of beneficial native species while suppressing weedy invasives may be challenging. Two approaches commonly used in management of terrestrial plant communities may be useful in this context: (1) altering resource availability and (2) establishing desirable species before weeds can invade (priority effects). However, these approaches are rarely used in aquatic systems, despite widespread need for sustainable solutions to aquatic weed problems. In artificial stream channels in California, USA, I conducted experiments with asexual propagules of non-native invasive Myriophyllum spicatum (Eurasian watermilfoil) and native Elodea nuttallii (western waterweed) to address the questions: (1) How does light availability affect relative performance of the two species?; (2) Does planting the native earlier than the invasive decrease survival or growth rate of the invasive?; and (3) Do light level and priority effects interact? The relative performance between E. nuttallii and M. spicatum had an interesting and unexpected pattern: M. spicatum had higher growth rates than E. nuttallii in the zero and medium shade levels, but had similar performance in the low and high shade levels. This pattern is most likely the result of E. nutallii's sensitivity to both very low and very high light, and M. spicatum's sensitivity to very low light only. Native priority did not significantly affect growth rate or survival of M. spicatum, possibly because of unexpectedly poor growth of the E. nuttallii planted early. This study suggests that altering light levels could be effective in reducing growth of an invasive macrophyte, and for changing the competitive balance between a native and a non-native species in the establishment phase. Further investigations into the use of priority effects and resource alteration for submersed macrophyte management are warranted, given their mixed results in other

  2. Discontinuous ephemeral streams

    NASA Astrophysics Data System (ADS)

    Bull, William B.

    1997-07-01

    Many ephemeral streams in western North America flowed over smooth valley floors before transformation from shallow discontinuous channels into deep arroyos. These inherently unstable streams of semiarid regions are sensitive to short-term climatic changes, and to human impacts, because hillslopes supply abundant sediment to infrequent large streamflow events. Discontinuous ephemeral streams appear to be constantly changing as they alternate between two primary modes of operation; either aggradation or degradation may become dominant. Attainment of equilibrium conditions is brief. Disequilibrium is promoted by channel entrenchment that causes the fall of local base level, and by deposition of channel fans that causes the rise of local base level. These opposing base-level processes in adjacent reaches are maintained by self-enhancing feedback mechanisms. The threshold between erosion and deposition is crossed when aggradational or degradational reaches shift upstream or downstream. Extension of entrenched reaches into channel fans tends to create continuous arroyos. Upvalley migration of fan apexes tends to create depositional valley floors with few stream channels. Less than 100 years is required for arroyo cutting, but more than 500 years is required for complete aggradation of entrenched stream channels and valley floors. Discontinuous ephemeral streams have a repetitive sequence of streamflow characteristics that is as distinctive as sequences of meander bends or braided gravel bars in perennial rivers. The sequence changes from degradation to aggradation — headcuts concentrate sheetflow, a single trunk channel conveys flow to the apex of a channel fan, braided distributary channels end in an area of diverging sheetflow, and converging sheetflow drains to headcuts. The sequence is repeated at intervals ranging from 15 m for small streams to more than 10 km for large streams. Lithologic controls on the response of discontinuous ephemeral streams include: (1

  3. 23 CFR 752.10 - Abandoned vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Abandoned vehicles. 752.10 Section 752.10 Highways... ROADSIDE DEVELOPMENT § 752.10 Abandoned vehicles. (a) Abandoned motor vehicles may be removed from the... collection of abandoned motor vehicles from within the right-of-way must be a development project and not...

  4. 23 CFR 752.10 - Abandoned vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Abandoned vehicles. 752.10 Section 752.10 Highways... ROADSIDE DEVELOPMENT § 752.10 Abandoned vehicles. (a) Abandoned motor vehicles may be removed from the... collection of abandoned motor vehicles from within the right-of-way must be a development project and not...

  5. 32 CFR 644.496 - Abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Abandonment. 644.496 Section 644.496 National... Abandonment. Abandonment, as used herein, has reference to cases where the lessor or a permittor Government.... Abandonment as authorized herein will not be a means for dropping accountability or responsibility...

  6. 32 CFR 644.496 - Abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Abandonment. 644.496 Section 644.496 National... Abandonment. Abandonment, as used herein, has reference to cases where the lessor or a permittor Government.... Abandonment as authorized herein will not be a means for dropping accountability or responsibility...

  7. 32 CFR 644.496 - Abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Abandonment. 644.496 Section 644.496 National... Abandonment. Abandonment, as used herein, has reference to cases where the lessor or a permittor Government.... Abandonment as authorized herein will not be a means for dropping accountability or responsibility...

  8. 18 CFR 157.216 - Abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 18 Conservation of Power and Water Resources 1 2012-04-01 2012-04-01 false Abandonment. 157.216... NECESSITY AND FOR ORDERS PERMITTING AND APPROVING ABANDONMENT UNDER SECTION 7 OF THE NATURAL GAS ACT... Transactions and Abandonment § 157.216 Abandonment. (a) Automatic authorization. The certificate holder...

  9. 32 CFR 644.496 - Abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Abandonment. 644.496 Section 644.496 National... Abandonment. Abandonment, as used herein, has reference to cases where the lessor or a permittor Government.... Abandonment as authorized herein will not be a means for dropping accountability or responsibility...

  10. 32 CFR 644.496 - Abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Abandonment. 644.496 Section 644.496 National... Abandonment. Abandonment, as used herein, has reference to cases where the lessor or a permittor Government.... Abandonment as authorized herein will not be a means for dropping accountability or responsibility...

  11. Remediation of abandoned mine discharges in the Loyalhanna Creek watershed

    SciTech Connect

    Fish, C.L.; Fish, D.H.

    1999-07-01

    Abandoned deep mine discharges were responsible for high iron loadings into several streams in the Loyalhanna Creek watershed. A total of seven discharges with flow rates from 20 to 1240 gal/min were flowing into Four Mile Run near Latrobe, PA. The iron concentrations in these discharges averaged near 80 ppm. The pH, however, was near neutral due to contact with underground limestone deposits. The high iron concentrations had severely degraded the habitat of the streams including 22 miles of Loyalhanna Creek. Benthic macroinvertebrates are especially vulnerable to the deposition of iron in these streams. In 1993, the Loyalhanna Mine Drainage Coalition was formed to oversee the remediation of the AMD discharges affecting Loyalhanna Creek. During this time monthly monitoring of the discharges began. Then using the chemistry and flow data, passive wetland treatment systems were designed to remediate the mine drainage. The remediation process precipitates and collects the iron oxide in the wetlands, thus eliminating the iron precipitation from the stream. In 1997 and 1998 three wetland treatment systems were constructed. The three wetlands capture the flow from the seven discharges and during low flow periods remove 95--100% of the iron from these discharges. The affected streams have shown a significant decrease in the iron concentrations and a subsequent improvement in the habitat quality of the streams. Fish and macroinvertebrates have been found in the most polluted stream which was void of life before the treatment systems were in operation.

  12. Human impacts to mountain streams

    NASA Astrophysics Data System (ADS)

    Wohl, Ellen

    2006-09-01

    Mountain streams are here defined as channel networks within mountainous regions of the world. This definition encompasses tremendous diversity of physical and biological conditions, as well as history of land use. Human effects on mountain streams may result from activities undertaken within the stream channel that directly alter channel geometry, the dynamics of water and sediment movement, contaminants in the stream, or aquatic and riparian communities. Examples include channelization, construction of grade-control structures or check dams, removal of beavers, and placer mining. Human effects can also result from activities within the watershed that indirectly affect streams by altering the movement of water, sediment, and contaminants into the channel. Deforestation, cropping, grazing, land drainage, and urbanization are among the land uses that indirectly alter stream processes. An overview of the relative intensity of human impacts to mountain streams is provided by a table summarizing human effects on each of the major mountainous regions with respect to five categories: flow regulation, biotic integrity, water pollution, channel alteration, and land use. This table indicates that very few mountains have streams not at least moderately affected by land use. The least affected mountainous regions are those at very high or very low latitudes, although our scientific ignorance of conditions in low-latitude mountains in particular means that streams in these mountains might be more altered than is widely recognized. Four case studies from northern Sweden (arctic region), Colorado Front Range (semiarid temperate region), Swiss Alps (humid temperate region), and Papua New Guinea (humid tropics) are also used to explore in detail the history and effects on rivers of human activities in mountainous regions. The overview and case studies indicate that mountain streams must be managed with particular attention to upstream/downstream connections, hillslope/channel

  13. Bearing the risk of abandonment

    SciTech Connect

    Attanasio, Donna M.

    2010-05-15

    In Order Nos. 679 and 679-A, FERC adopted a policy of authorizing rate incentives for new transmission early in the development process to encourage transmission investment. The abandoned-plant cost recovery incentive creates a tension between ratepayer and investor interests, which is increasingly reflected in FERC's orders. (author)

  14. Riparian deforestation, stream narrowing, and loss of stream ecosystem services

    PubMed Central

    Sweeney, Bernard W.; Bott, Thomas L.; Jackson, John K.; Kaplan, Louis A.; Newbold, J. Denis; Standley, Laurel J.; Hession, W. Cully; Horwitz, Richard J.

    2004-01-01

    A study of 16 streams in eastern North America shows that riparian deforestation causes channel narrowing, which reduces the total amount of stream habitat and ecosystem per unit channel length and compromises in-stream processing of pollutants. Wide forest reaches had more macroinvertebrates, total ecosystem processing of organic matter, and nitrogen uptake per unit channel length than contiguous narrow deforested reaches. Stream narrowing nullified any potential advantages of deforestation regarding abundance of fish, quality of dissolved organic matter, and pesticide degradation. These findings show that forested stream channels have a wider and more natural configuration, which significantly affects the total in-stream amount and activity of the ecosystem, including the processing of pollutants. The results reinforce both current policy of the United States that endorses riparian forest buffers as best management practice and federal and state programs that subsidize riparian reforestation for stream restoration and water quality. Not only do forest buffers prevent nonpoint source pollutants from entering small streams, they also enhance the in-stream processing of both nonpoint and point source pollutants, thereby reducing their impact on downstream rivers and estuaries. PMID:15381768

  15. 37 CFR 2.65 - Abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Abandonment. 2.65 Section 2... Abandonment. (a) If an applicant fails to respond, or to respond completely, within six months after the date... avoids abandonment of an application. (b) When action by the applicant filed within the...

  16. 37 CFR 2.65 - Abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Abandonment. 2.65 Section 2... Abandonment. (a) If an applicant fails to respond, or to respond completely, within six months after the date... avoids abandonment of an application. (b) When action by the applicant filed within the...

  17. 37 CFR 2.65 - Abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Abandonment. 2.65 Section 2... Abandonment. (a) If an applicant fails to respond, or to respond completely, within six months after the date... avoids abandonment of an application. (b) When action by the applicant filed within the...

  18. 37 CFR 2.65 - Abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Abandonment. 2.65 Section 2... Abandonment. (a) If an applicant fails to respond, or to respond completely, within six months after the date... avoids abandonment of an application. (b) When action by the applicant filed within the...

  19. 37 CFR 2.65 - Abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Abandonment. 2.65 Section 2... Abandonment. (a) If an applicant fails to respond, or to respond completely, within six months after the date... avoids abandonment of an application. (b) When action by the applicant filed within the...

  20. 18 CFR 157.216 - Abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 18 Conservation of Power and Water Resources 1 2011-04-01 2011-04-01 false Abandonment. 157.216 Section 157.216 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT... facilities to be abandoned. (5) For any abandonment resulting in earth disturbance, a USGS...

  1. 18 CFR 157.216 - Abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 18 Conservation of Power and Water Resources 1 2014-04-01 2014-04-01 false Abandonment. 157.216 Section 157.216 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT... facilities to be abandoned. (5) For any abandonment resulting in earth disturbance, a USGS...

  2. 18 CFR 157.216 - Abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 18 Conservation of Power and Water Resources 1 2013-04-01 2013-04-01 false Abandonment. 157.216 Section 157.216 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION, DEPARTMENT... facilities to be abandoned. (5) For any abandonment resulting in earth disturbance, a USGS...

  3. 7 CFR 767.51 - Property abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 7 2010-01-01 2010-01-01 false Property abandonment. 767.51 Section 767.51... AGRICULTURE SPECIAL PROGRAMS INVENTORY PROPERTY MANAGEMENT Property Abandonment and Personal Property Removal § 767.51 Property abandonment. The Agency will take actions necessary to secure, maintain,...

  4. 7 CFR 767.51 - Property abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 7 2011-01-01 2011-01-01 false Property abandonment. 767.51 Section 767.51... AGRICULTURE SPECIAL PROGRAMS INVENTORY PROPERTY MANAGEMENT Property Abandonment and Personal Property Removal § 767.51 Property abandonment. The Agency will take actions necessary to secure, maintain,...

  5. AN INTERREGIONAL COMPARISON OF CHANNEL STRUCTURE, TRANSIENT STORAGE, AND RIPARIAN COVER WITH COMMUNITY METABOLISM IN STREAMS DRAINING EARLY- AND MID-SUCCESSIONAL WATERSHEDS

    EPA Science Inventory

    The goal of this research was to evaluate stream ecosystem function in response to different forest harvest intensities and time since harvest. Research was conducted in North Carolina, Arkansas, Oregon, and California.

  6. Legacy soil contamination at abandoned mine sites: making a case for guidance on soil protection.

    PubMed

    Kostarelos, Konstantinos; Gavriel, Ifigenia; Stylianou, Marinos; Zissimos, Andreas M; Morisseau, Eleni; Dermatas, Dimitris

    2015-03-01

    Within the European Union, guidance in the form of a uniform Soil Directive does not exist and member states are left to enact their own legislation governing historic soil contamination. Several historic or "legacy" sites exist in Cyprus - an EU member state with a long history of mining and a significant number of abandoned mining sites. The gold-silver enrichment plant of Mitsero village was abandoned 70 years ago, yet soil samples inside and outside the plant were extremely low in pH, exhibited high leachability of heavy metals and high cyanide levels. Water samples collected from an ephemeral stream located down-gradient of the site contained high levels of heavy metals. Two abandoned open-pit mines (Kokkinopezoula and Mathiatis) were investigated, where elevated metal content in soil samples from the surrounding streams and spoil heaps, and extremely low pH and high metal content in water samples from the mine crater were measured. PMID:25600021

  7. Stream biogeochemical and suspended sediment responses to permafrost degradation in stream banks in Taylor Valley, Antarctica

    NASA Astrophysics Data System (ADS)

    Gooseff, Michael N.; Van Horn, David; Sudman, Zachary; McKnight, Diane M.; Welch, Kathleene A.; Lyons, William B.

    2016-03-01

    Stream channels in the McMurdo Dry Valleys are characteristically wide, incised, and stable. At typical flows, streams occupy a fraction of the oversized channels, providing habitat for algal mats. In January 2012, we discovered substantial channel erosion and subsurface thermomechanical erosion undercutting banks of the Crescent Stream. We sampled stream water along the impacted reach and compared concentrations of solutes to the long-term data from this stream ( ˜ 20 years of monitoring). Thermokarst-impacted stream water demonstrated higher electrical conductivity, and concentrations of chloride, sulfate, sodium, and nitrate than the long-term medians. These results suggest that this mode of lateral permafrost degradation may substantially impact stream solute loads and potentially fertilize stream and lake ecosystems. The potential for sediment to scour or bury stream algal mats is yet to be determined, though it may offset impacts of associated increased nutrient loads to streams.

  8. REACH SPECIFIC CHANNEL STABILIZATION BASED ON COMPREHENSIVE EVALUATION OF VALLEY FILL HISTORY, ALLUVIAL ARCHITECTURE AND GROUNDWATER HYDROLOGY IN A MOUNTAIN STREAM IN THE CENTRAL GREAT BASIN, NEVADA

    EPA Science Inventory

    Kingston meadow, located in the Toiyabe Range, is one of many wet meadow complexes threatened by rapid channel incision in the mountain ranges of the central Great Basin. Channel incision can lower the baselevel for groundwater discharge and de-water meadow complexes resulting in...

  9. Stream dynamics at pipeline river crossings

    SciTech Connect

    Beckstead, G.R.E.; Cavers, D.S.

    1996-12-31

    Pipeline crossings of streams, whether large or small, must consider the ability of the stream channel to scour its bed and erode its banks. Case studies are presented to illustrate the kinds of dynamic environments which must be considered in designing pipeline stream crossings. These characteristics may be determined through the use of comparative historical aerial photography and site photographs and surveys. The case studies presented as examples in this paper include gullies, bedrock-lined channels, entrenched meandering streams, multi-channel wandering streams, degrading channels, alluvial fans, and major channels affected by regulation and man-made structures. Natural hazards such as debris jams and beaver dams are also discussed. For each case study, the characteristics of the channels are described, the design approach discussed and site-specific constraints presented which affected the final design.

  10. Multiple factors drive regional agricultural abandonment.

    PubMed

    Osawa, Takeshi; Kohyama, Kazunori; Mitsuhashi, Hiromune

    2016-01-15

    An understanding of land-use change and its drivers in agroecosystems is important when developing adaptations to future environmental and socioeconomic pressures. Agricultural abandonment occurs worldwide with multiple potentially positive and negative consequences; however, the main factors causing agricultural abandonment in a country i.e., at the macro scale, have not been identified. We hypothesized that socio-environmental factors driving agricultural abandonment could be summarized comprehensively into two, namely "natural" and "social", and the relative importance of these differs among regions. To test this postulate, we analyzed the factors currently leading to agricultural abandonment considering ten natural environment variables (e.g., temperature) and five social variables (e.g., number of farmers) using the random forest machine learning method after dividing Japan into eight regions. Our results showed that agricultural abandonment was driven by various socio-environmental factors, and the main factors leading to agricultural abandonment differed among regions, especially in Hokkaido in northern Japan. Hokkaido has a relatively large area of concentrated farmland, and abandonment might have resulted from the effectiveness of cultivation under specific climate factors, whereas the other regions have relatively small areas of farmland with many elderly part-time farmers. In such regions, abandonment might have been caused by the decreasing numbers of potential farmers. Thus, two different drivers of agricultural abandonment were found: inefficient cultivation and decreasing numbers of farmers. Therefore, agricultural abandonment cannot be prevented by adopting a single method or policy. Agricultural abandonment is a significant problem not only for food production but also for several ecosystem services. Governments and decision-makers should develop effective strategies to prevent further abandonment to ensure sustainable future management of agro-ecosystems.

  11. Multiple factors drive regional agricultural abandonment.

    PubMed

    Osawa, Takeshi; Kohyama, Kazunori; Mitsuhashi, Hiromune

    2016-01-15

    An understanding of land-use change and its drivers in agroecosystems is important when developing adaptations to future environmental and socioeconomic pressures. Agricultural abandonment occurs worldwide with multiple potentially positive and negative consequences; however, the main factors causing agricultural abandonment in a country i.e., at the macro scale, have not been identified. We hypothesized that socio-environmental factors driving agricultural abandonment could be summarized comprehensively into two, namely "natural" and "social", and the relative importance of these differs among regions. To test this postulate, we analyzed the factors currently leading to agricultural abandonment considering ten natural environment variables (e.g., temperature) and five social variables (e.g., number of farmers) using the random forest machine learning method after dividing Japan into eight regions. Our results showed that agricultural abandonment was driven by various socio-environmental factors, and the main factors leading to agricultural abandonment differed among regions, especially in Hokkaido in northern Japan. Hokkaido has a relatively large area of concentrated farmland, and abandonment might have resulted from the effectiveness of cultivation under specific climate factors, whereas the other regions have relatively small areas of farmland with many elderly part-time farmers. In such regions, abandonment might have been caused by the decreasing numbers of potential farmers. Thus, two different drivers of agricultural abandonment were found: inefficient cultivation and decreasing numbers of farmers. Therefore, agricultural abandonment cannot be prevented by adopting a single method or policy. Agricultural abandonment is a significant problem not only for food production but also for several ecosystem services. Governments and decision-makers should develop effective strategies to prevent further abandonment to ensure sustainable future management of agro

  12. 49 CFR 195.59 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Abandonment or deactivation of facilities. 195.59... Abandonment or deactivation of facilities. For each abandoned offshore pipeline facility or each abandoned... operator of that facility must file a report upon abandonment of that facility. (a) The preferred method...

  13. 49 CFR 195.59 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Abandonment or deactivation of facilities. 195.59... Abandonment or deactivation of facilities. For each abandoned offshore pipeline facility or each abandoned... operator of that facility must file a report upon abandonment of that facility. (a) The preferred method...

  14. 49 CFR 195.59 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Abandonment or deactivation of facilities. 195.59... Abandonment or deactivation of facilities. For each abandoned offshore pipeline facility or each abandoned... operator of that facility must file a report upon abandonment of that facility. (a) The preferred method...

  15. 49 CFR 195.59 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Abandonment or deactivation of facilities. 195.59... Abandonment or deactivation of facilities. For each abandoned offshore pipeline facility or each abandoned... operator of that facility must file a report upon abandonment of that facility. (a) The preferred method...

  16. Application of electromagnetic techniques in survey of contaminated groundwater at an abandoned mine complex in southwestern Indiana, U.S.A.

    USGS Publications Warehouse

    Brooks, G.A.; Olyphant, G.A.; Harper, D.

    1991-01-01

    In part of a large abandoned mining complex, electromagnetic geophysical surveys were used along with data derived from cores and monitoring wells to infer sources of contamination and subsurface hydrologic connections between acidic refuse deposits and adjacent undisturbed geologic materials. Electrical resistivity increases sharply along the boundary of an elevated deposit of pyritic coarse refuse, which is highly contaminated and electrically conductive, indicating poor subsurface hydrologic connections with surrounding deposits of fine refuse and undisturbed glacial material. Groundwater chemistry, as reflected in values of specific conductance, also differs markedly across the deposit's boundary, indicating that a widespread contaminant plume has not developed around the coarse refuse in more than 40 yr since the deposit was created. Most acidic drainage from the coarse refuse is by surface runoff and is concentrated around stream channels. Although most of the contaminated groundwater within the study area is concentrated within the surficial refuse deposits, transects of apparent resistivity and phase angle indicate the existence of an anomalous conductive layer at depth (>4 m) in thick alluvial sediments along the northern boundary of the mining complex. Based on knowledge of local geology, the anomaly is interpreted to represent a subsurface connection between the alluvium and a flooded abandoned underground mine. ?? 1991 Springer-Verlag New York Inc.

  17. Application of electromagnetic techniques in survey of contaminated groundwater at an abandoned mine complex in southwestern Indiana, U.S.A.

    NASA Astrophysics Data System (ADS)

    Brooks, Glenn A.; Olyphant, Greg A.; Harper, Denver

    1991-07-01

    In part of a large abandoned mining complex, electromagnetic geophysical surveys were used along with data derived from cores and monitoring wells to infer sources of contamination and subsurface hydrologic connections between acidic refuse deposits and adjacent undisturbed geologic materials. Electrical resistivity increases sharply along the boundary of an elevated deposit of pyritic coarse refuse, which is highly contaminated and electrically conductive, indicating poor subsurface hydrologic connections with surrounding deposits of fine refuse and undisturbed glacial material. Groundwater chemistry, as reflected in values of specific conductance, also differs markedly across the deposit's boundary, indicating that a widespread contaminant plume has not developed around the coarse refuse in more than 40 yr since the deposit was created. Most acidic drainage from the coarse refuse is by surface runoff and is concentrated around stream channels. Although most of the contaminated groundwater within the study area is concentrated within the surficial refuse deposits, transects of apparent resistivity and phase angle indicate the existence of an anomalous conductive layer at depth (>4 m) in thick alluvial sediments along the northern boundary of the mining complex. Based on knowledge of local geology, the anomaly is interpreted to represent a subsurface connection between the alluvium and a flooded abandoned underground mine.

  18. A Radar and DC Resistivity Survey of Arid Ephemeral Stream Systems Near Yuma, AZ.: Bedrock Morphology, Channel Stratigraphy, and Soil Moisture Content

    NASA Astrophysics Data System (ADS)

    Genco, A. J.; Harry, D. L.

    2011-12-01

    Ground Penetrating Radar (GPR), Direct Current (DC) Electrical Resistivity, and laboratory resistivity measurements were collected to determine the depth to bedrock, subsurface stratigraphy, and spatial variations in soil moisture in fluvial channels in the arid Sonoran Desert region near Yuma, AZ. Six sites were surveyed, three each at Yuma and Mohave Washes, which are two minimally disturbed ephemeral channel systems. The purpose of the survey is to determine whether large vegetation present in the larger channels is sustained primarily by soil moisture, or by rooting below the water table within the fractured bedrock. An abrupt change in the GPR character marks the contact between bedrock and alluvium, from abundant coherent reflections in the alluvium to minimal weak reflections and occasional diffractions in the bedrock. Bedrock depths range from approximately 1 to 5 m at Mohave Wash, with the greater depths corresponding with the larger channels in the wash. At Yuma Wash the contact between bedrock and alluvium ranges from approximately 1 to 4 m depth, also with the greater depths being associated with the larger channels. Resistivity in the subsurface at Mohave Wash ranges from 130-1100 μ-m in the upper 2 m and from 15-130 μ-m below 2-5 m depth. At Yuma Wash, the resistivity ranges from 46-500 μ-m in the upper 1 m, and from 4-46 μ-m below approximately 1-4 m depth. Preliminary interpretation indicates that the potential root zone within the soil is limited to relatively shallow depths, less than 5 m thick in the places surveyed, with the soil likely being unsaturated above 1-2 m.

  19. 32 CFR 636.31 - Abandoned vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Abandoned vehicles. 636.31 Section 636.31... CRIMINAL INVESTIGATIONS MOTOR VEHICLE TRAFFIC SUPERVISION (SPECIFIC INSTALLATIONS) Fort Stewart, Georgia § 636.31 Abandoned vehicles. (a) Any MP or DOD police officer who finds or has knowledge of a...

  20. 7 CFR 767.51 - Property abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... jeopardy, the Agency will take the above actions prior to completing servicing actions contained in 7 CFR... 7 Agriculture 7 2013-01-01 2013-01-01 false Property abandonment. 767.51 Section 767.51... AGRICULTURE SPECIAL PROGRAMS INVENTORY PROPERTY MANAGEMENT Property Abandonment and Personal Property...

  1. 36 CFR 13.122 - Abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Abandonment. 13.122 Section 13.122 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Cabins General Provisions § 13.122 Abandonment. (a) An existing cabin...

  2. 36 CFR 13.122 - Abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Abandonment. 13.122 Section 13.122 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Cabins General Provisions § 13.122 Abandonment. (a) An existing cabin...

  3. 36 CFR 13.122 - Abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Abandonment. 13.122 Section 13.122 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Cabins General Provisions § 13.122 Abandonment. (a) An existing cabin...

  4. 7 CFR 767.51 - Property abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... jeopardy, the Agency will take the above actions prior to completing servicing actions contained in 7 CFR... 7 Agriculture 7 2014-01-01 2014-01-01 false Property abandonment. 767.51 Section 767.51... AGRICULTURE SPECIAL PROGRAMS INVENTORY PROPERTY MANAGEMENT Property Abandonment and Personal Property...

  5. 20 CFR 345.206 - Abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 1 2012-04-01 2012-04-01 false Abandonment. 345.206 Section 345.206 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Individual Employer Records § 345.206 Abandonment. If...

  6. 20 CFR 345.206 - Abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 1 2013-04-01 2012-04-01 true Abandonment. 345.206 Section 345.206 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Individual Employer Records § 345.206 Abandonment. If an...

  7. 20 CFR 345.206 - Abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 1 2011-04-01 2011-04-01 false Abandonment. 345.206 Section 345.206 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Individual Employer Records § 345.206 Abandonment. If...

  8. 20 CFR 345.206 - Abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Abandonment. 345.206 Section 345.206 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Individual Employer Records § 345.206 Abandonment. If...

  9. 7 CFR 767.51 - Property abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... jeopardy, the Agency will take the above actions prior to completing servicing actions contained in 7 CFR... 7 Agriculture 7 2012-01-01 2012-01-01 false Property abandonment. 767.51 Section 767.51... AGRICULTURE SPECIAL PROGRAMS INVENTORY PROPERTY MANAGEMENT Property Abandonment and Personal Property...

  10. 20 CFR 345.206 - Abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 1 2014-04-01 2012-04-01 true Abandonment. 345.206 Section 345.206 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE RAILROAD UNEMPLOYMENT INSURANCE ACT EMPLOYERS' CONTRIBUTIONS AND CONTRIBUTION REPORTS Individual Employer Records § 345.206 Abandonment. If an...

  11. 36 CFR 13.122 - Abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Abandonment. 13.122 Section 13.122 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Cabins General Provisions § 13.122 Abandonment. (a) An existing cabin...

  12. 36 CFR 13.122 - Abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Abandonment. 13.122 Section 13.122 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Cabins General Provisions § 13.122 Abandonment. (a) An existing cabin...

  13. Evolution of abandoned underground hardrock mine closures by the Texas abandoned mine land reclamation program

    SciTech Connect

    Rhodes, M.J.

    1997-12-31

    The Texas Abandoned Mine Land (AML) Reclamation program began investigating, designing and implementing hard rock abandoned underground mine closures, after a young boy fell to his death in an abandoned mine opening in 1982. This paper discusses the evolution of abandoned hard rock mine closures in west Texas, by the Texas AML program in response to the development of abandoned underground mine resource information. Case histories are presented of the Texas AML program`s efforts in west Texas including: mine history summaries; site characterization, environmental assessment; design and construction planning considerations, and construction cost information.

  14. Influence of riparian vegetation on channel widening and subsequent contraction on a sand-bed stream since European settlement: Widden Brook, Australia

    NASA Astrophysics Data System (ADS)

    Erskine, Wayne; Keene, Annabelle; Bush, Richard; Cheetham, Michael; Chalmers, Anita

    2012-04-01

    Widden Brook in the Hunter Valley, Australia, was first settled by Europeans in 1831 and had widened substantially by the 1870s due to frequent floods during a flood-dominated regime impacting on highly disturbed banks whose riparian trees had been either ringbarked or cleared, and whose understorey had been grazed. Catastrophic floods in 1950 (many), two in August 1952 and one in February 1955 effected the final phase of channel widening at the onset of a second flood-dominated regime more than half a century after the initial widening. Contraction has been active since 1963 by a combination of five biogeomorphic processes. Firstly, rapid channel widening, migration and cutoffs totally reworked the pre-European floodplain and were followed by active floodplain formation. Initial bar formation was replaced by sand splay and overbank deposition which constructed a new floodplain and narrower channel. Secondly, overwidened channel segments that were produced by the catastrophic 1955 flood have contracted since 1963 by the formation of up to four bank-attached, discontinuous benches below the floodplain. Each bench has a bar nucleus of pebbly coarse sand overlain by stratified fine-medium sand and mud. Colonisation by River Sheoaks (Casuarina cunninghamiana subsp. cunninghamiana) or grasses (Cynodon dactylon, Paspalum distichum, Pennisetum clandestinum) is important in converting bars to benches. Thirdly, narrower segments which developed since 1963 have contracted by small-scale accretion on both banks. These deposits are steeply dipping, interbedded sand and mud trapped by stoloniferous and rhizomatous grasses (C. dactylon, P. distichum, P. clandestinum) which also rapidly stabilise the deposits. Fourthly, rare laterally migrating, small radius bends have contracted by recent point bar formation greatly exceeding cutbank recession rates. Point bar formation is controlled by secondary currents producing inclined stratified coarse sands without the influence of

  15. Beaver dams and channel sediment dynamics on Odell Creek, Centennial Valley, Montana, USA

    NASA Astrophysics Data System (ADS)

    Levine, Rebekah; Meyer, Grant A.

    2014-01-01

    Beaver dams in streams are generally considered to increase bed elevation through in-channel sediment storage, thus, reintroductions of beaver are increasingly employed as a restoration tool to repair incised stream channels. Here we consider hydrologic and geomorphic characteristics of the study stream in relation to in-channel sediment storage promoted by beaver dams. We also document the persistence of sediment in the channel following breaching of dams. Nine reaches, containing 46 cross-sections, were investigated on Odell Creek at Red Rock Lakes National Wildlife Refuge, Centennial Valley, Montana. Odell Creek has a snowmelt-dominated hydrograph and peak flows between 2 and 10 m3 s- 1. Odell Creek flows down a fluvial fan with a decreasing gradient (0.018-0.004), but is confined between terraces along most of its length, and displays a mostly single-thread, variably sinuous channel. The study reaches represent the overall downstream decrease in gradient and sediment size, and include three stages of beaver damming: (1) active; (2) built and breached in the last decade; and (3) undammed. In-channel sediment characteristics and storage were investigated using pebble counts, fine-sediment depth measurements, sediment mapping and surveys of dam breaches. Upstream of dams, deposition of fine (≤ 2 mm) sediment is promoted by reduced water surface slope, shear stress and velocity, with volumes ranging from 48 to 182 m3. High flows, however, can readily transport suspended sediment over active dams. Variations in bed-sediment texture and channel morphology associated with active dams create substantial discontinuities in downstream trends and add to overall channel heterogeneity. Observations of abandoned dam sites and dam breaches revealed that most sediment stored above beaver dams is quickly evacuated following a breach. Nonetheless, dam remnants trap some sediment, promote meandering and facilitate floodplain development. Persistence of beaver dam sediment

  16. Key stream/sediment exchanges of water and heat near stream mouths

    NASA Astrophysics Data System (ADS)

    Constantz, J. E.; Naranjo, R. C.; Niswonger, R. G.; Neilson, B. T.; Allander, K.; Zamora, C.; Smith, D. W.; Stonestrom, D. A.

    2014-12-01

    The section of stream discharging to a lake or other surface-water body is referred to as the stream mouth, a stream reach with rapidly changing hydrologic conditions, leading to unique aquatic and benthic ecology, as well as a visibly active fishery habitat. Of environmental significance, bridges, control structures, channelization and foot traffic are common near stream mouths, warranting comparisons of natural and channelized stream mouths. The present work completes the first investigation focusing specifically on the hydrology of surface-water/sediment exchanges at stream-mouth reaches discharging to lakes and compares these exchanges to those measured along the nearby shoreline in both a qualitative and quantitative manner. Heat and water exchanges for two common types of stream mouths (a natural stream with a summer barrier bar and a channelized stream mouth) are compared with comparable exchanges along the nearby shoreline on the north shore of Lake Tahoe located in the Central Sierra Nevada Mountain Range (CA/NV, US). The study site was selected partially due the abundance of streams discharging into the lake of both a natural and channelized nature (~30 small streams with a large number of both types of stream mouths). Heat and water exchanges were both qualitatively and quantitatively distinct for the three types of hydrologic settings, with (1) cool, low velocity, longitudinal (hyporheic) flowpaths observed below the channelized stream mouth, discharging beneath the warmer, more buoyant lakeshore water, (2) the nearby shoreline receiving relatively warm, higher velocity discharge and (3) for the natural stream mouth, there was strong diurnal temperature pattern in groundwater discharging through the seasonal barrier beach to the lake. Impacts of strong 2013 wave action on exchanges were also distinct for the three settings, with (1) channelization allowing waves to extend well upstream, (2) a lesser invasive impact in the shoreline swash zone exchanges

  17. Modeling the Effects of Connecting Side Channels to the Long Tom River, Oregon

    NASA Astrophysics Data System (ADS)

    Appleby, C.; McDowell, P. F.

    2015-12-01

    The lower Long Tom River is a heavily managed, highly modified stream in the southwestern Willamette Valley with many opportunities for habitat improvements and river restoration. In the 1940s and 1950s, the US Army Corps of Engineers dramatically altered this river system by constructing the Fern Ridge Dam and three, large drop structures, converting the River from a highly sinuous channel to a straight, channelized stream that is interrupted by these grade control structures, and removed the majority of the riparian vegetation. As a result, juvenile spring Chinook salmon are no longer found in the Watershed and the local population of coastal cutthroat trout face limited aquatic habitat. When the river was channelized, long sections of the historical channel were left abandoned on the floodplain. Reconnecting these historical channels as side channels may improve the quality and quantity of aquatic habitat and could allow fish passage around current barriers. However, such construction may also lead to undesirable threats to infrastructure and farmland. This study uses multiple HEC-RAS models to determine the impact of reconnecting two historical channels to the lower Long Tom River by quantifying the change in area of flood inundation and identifying infrastructure in jeapordy given current and post-restoration conditions for 1.5, 5, 10, and 25-year flood discharges. Bathymetric data from ADCP and RTK-GPS surveys has been combined with LiDAR-derived topographic data to create continuous elevation models. Several types of side channel connections are modeled in order to determine which type of connection will result in both the greatest quantity of accessible habitat and the fewest threats to public and private property. In the future, this study will also consider the change in the quantity of physical salmonid habitat and map the areas prone to sedimentation and erosion using CEASAR and PHABSIM tools.

  18. Coevolution of hydrodynamics, vegetation and channel evolution in wetlands of a semi-arid floodplain

    NASA Astrophysics Data System (ADS)

    Seoane, Manuel; Rodriguez, Jose Fernando; Rojas, Steven Sandi; Saco, Patricia Mabel; Riccardi, Gerardo; Saintilan, Neil; Wen, Li

    2015-04-01

    The Macquarie Marshes are located in the semi-arid region in north western NSW, Australia, and constitute part of the northern Murray-Darling Basin. The Marshes are comprised of a system of permanent and semi-permanent marshes, swamps and lagoons interconnected by braided channels. The wetland complex serves as nesting place and habitat for many species of water birds, fish, frogs and crustaceans, and portions of the Marshes was listed as internationally important under the Ramsar Convention. Some of the wetlands have undergone degradation over the last four decades, which has been attributed to changes in flow management upstream of the marshes. Among the many characteristics that make this wetland system unique is the occurrence of channel breakdown and channel avulsion, which are associated with decline of river flow in the downstream direction typical of dryland streams. Decrease in river flow can lead to sediment deposition, decrease in channel capacity, vegetative invasion of the channel, overbank flows, and ultimately result in channel breakdown and changes in marsh formation. A similar process on established marshes may also lead to channel avulsion and marsh abandonment, with the subsequent invasion of terrestrial vegetation. All the previous geomorphological evolution processes have an effect on the established ecosystem, which will produce feedbacks on the hydrodynamics of the system and affect the geomorphology in return. In order to simulate the complex dynamics of the marshes we have developed an ecogeomorphological modelling framework that combines hydrodynamic, vegetation and channel evolution modules and in this presentation we provide an update on the status of the model. The hydrodynamic simulation provides spatially distributed values of inundation extent, duration, depth and recurrence to drive a vegetation model based on species preference to hydraulic conditions. It also provides velocities and shear stresses to assess geomorphological

  19. Stream Processors

    NASA Astrophysics Data System (ADS)

    Erez, Mattan; Dally, William J.

    Stream processors, like other multi core architectures partition their functional units and storage into multiple processing elements. In contrast to typical architectures, which contain symmetric general-purpose cores and a cache hierarchy, stream processors have a significantly leaner design. Stream processors are specifically designed for the stream execution model, in which applications have large amounts of explicit parallel computation, structured and predictable control, and memory accesses that can be performed at a coarse granularity. Applications in the streaming model are expressed in a gather-compute-scatter form, yielding programs with explicit control over transferring data to and from on-chip memory. Relying on these characteristics, which are common to many media processing and scientific computing applications, stream architectures redefine the boundary between software and hardware responsibilities with software bearing much of the complexity required to manage concurrency, locality, and latency tolerance. Thus, stream processors have minimal control consisting of fetching medium- and coarse-grained instructions and executing them directly on the many ALUs. Moreover, the on-chip storage hierarchy of stream processors is under explicit software control, as is all communication, eliminating the need for complex reactive hardware mechanisms.

  20. Channel change as a response to reforestation and population decline in the rural Toulourenc basin, southern French Prealps

    NASA Astrophysics Data System (ADS)

    Rubin, Z.; Janes, K.; Kondolf, G. M.; Natali, J.; Radke, J.

    2011-12-01

    As a result of demographic changes, forest cover in the southern French Prealp mountains has increased dramatically during the 20th century. Over the same time period stream morphology within these sub-Mediterranean mountain basins has also changed. At two mainstem locations and eight upstream tributary sites within the Toulourenc basin (~150 km2), we investigated the relationship between hillslope erosion processes and the evolution of stream channel morphology through analysis of historic cadastral maps (circa 1850), aerial photographs (1950-current), topographic surveys (2009-2011), dendrochronolgy of vegetative establishment on abandoned terraces, and bed material size distribution. We observed narrowing of the active channel width, channel degradation, and pavement development along the Toulourenc mainstem and upstream tributaries. On the mainstem Toulourenc, the active channel has narrowed approximately 50% (30m) between 1950 and 2011. As with other studies within the southern French Prealps, the channel modifications appear to be induced by a decrease in the coarse sediment supply as agricultural and logging lands were reforested between 1890 and 1945.

  1. GEOMORPHIC CONTROLS ON C AND N PROCESSING IN A RESTORED URBAN STREAM; POWER POINT PRESENTATION

    EPA Science Inventory

    Stream channel incision due to hydraulic alteration stemming from urbanization may cause a disconnection between the stream channel and the adjacent floodplain. This disconnection may inhibit removal of nitrate via denitrification and/or stimulate nitrate production through nitr...

  2. Water availability controls on community structure of an ephemeral meltwater stream ecosystem in the McMurdo Dry Valleys

    NASA Astrophysics Data System (ADS)

    McKnight, D. M.; Simmons, B.; Stanish, L.

    2009-05-01

    The McMurdo Dry Valleys of Antarctica contain many glacial meltwater streams that flow during the summer into lakes on the valley floors. Many streams have thriving cyanobacterial mats that are freeze-dried in winter and begin photosynthesis when flow arrives. We studied the community structure in a formerly abandoned channel, which was reactivated by a flow diversion in 1994. Cyanobacterial mats became abundant in the reactivated channel within a week and have remained evident even through cold, low flow summers. We recently compared the abundance and species distribution of invertebrates and diatoms in the cyanobacterial mats and in hyporheic zone during cold (low flow) and warm (high flow) summers. During the warm summer, there were sites where the invertebrate abundance was greater in the mats than in the underlying hyporheic sediments. In contrast, during the cold summer the invertebrate biomass was lower in the mats than in the hyporheic sediments. These findings suggest that the optimal micro-habitat for invertebrates in these mats and sediments is partially driven by ephemeral stream hydrology. This limitation on potential invertebrate grazers (which are important nutrient transformers) may account for the accumulation of algal biomass and subsequent nutrient immobilization in the mats over many summers.

  3. Nitrogen Dynamics in a Degraded Urban Stream: Can the Patient be Revived? (Balitmore, MD)

    EPA Science Inventory

    Urbanization degrades stream ecosystems by altering hydrology and nutrient dynamics. We investigated temporal and spatial patterns in biogeochemistry and hydrology in and near the stream channel of a geomorphically degraded urban stream of Baltimore County, Maryland, USA. Our o...

  4. Nitrogen dynamics at the ground water-surface water interface of a degraded urban stream

    EPA Science Inventory

    Urbanization degrades stream ecosystems by altering hydrology and nutrient dynamics. We investigated temporal and spatial patterns in biogeochemistry and hydrology in and near the stream channel of a geomorphically degraded urban stream of Baltimore County, Maryland, USA. Our o...

  5. Continued distress among abandoned dogs in Fukushima.

    PubMed

    Nagasawa, Miho; Mogi, Kazutaka; Kikusui, Takefumi

    2012-01-01

    In Fukushima, Japan, a prolonged refugee situation caused by a major nuclear incident after the earthquake of March 11, 2011 has led to the unintentional abandonment of many pets. We received stray or abandoned dogs from rescue centers in Fukushima Prefecture. During re-socialization training and health care, we accessed the behavioral characteristics and the urine cortisol level of each dog and compared them with those of other abandoned dogs not involved in this earthquake. The dogs from Fukushima showed significantly lower aggression toward unfamiliar people, trainability, and attachment to their caretakers; also, urine cortisol levels in the dogs from Fukushima were 5-10-fold higher than those in abandoned dogs from another area of Japan. These results suggested that the dogs from Fukushima suffered through an extremely stressful crisis. PMID:23061007

  6. Governments grapple with abandonment fiscal terms

    SciTech Connect

    Pittard, A.

    1997-12-08

    Governments worldwide are grappling with ways in which to treat offshore-facility abandonment and oil and gas field abandonment in their fiscal and environmental legislation. While some governments have introduced fiscal and environmental provisions for removing offshore installations, much of the legislation remains to be tested in practice. Many other governments have yet to introduce specific terms and legislation regarding the process. The method for financing offshore facilities abandonment must be agreed upon between the operators and countries. Carryback provisions typically are the most economically efficient, otherwise all parties lose out. Overall, because every country competes for a finite amount of funds, any hindrance to project profitability will ultimately hurt the government and therefore the continuation of economic development in the country. The paper discusses abandonment issues and costs, fiscal provisions, fiscal provision effects, and company preferences.

  7. 33 CFR 245.45 - Abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... will be made by the District Engineer based on the degree of hazard to navigation, the difficulty and... or 30 days of public notice, abandonment is presumed. (d) Cargo. If vessel and cargo are...

  8. 33 CFR 245.45 - Abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... will be made by the District Engineer based on the degree of hazard to navigation, the difficulty and... or 30 days of public notice, abandonment is presumed. (d) Cargo. If vessel and cargo are...

  9. 32 CFR 644.494 - Donation, abandonment or destruction.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Donation, abandonment or destruction. 644.494... Land) § 644.494 Donation, abandonment or destruction. (a) General. Improvements may be abandoned... from its sale, or that abandonment or destruction is required by military necessity, or...

  10. 37 CFR 2.68 - Express abandonment (withdrawal) of application.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Express abandonment... Action by Applicants § 2.68 Express abandonment (withdrawal) of application. (a) Written document required. An applicant may expressly abandon an application by filing a written request for abandonment...

  11. 49 CFR 192.727 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 3 2011-10-01 2011-10-01 false Abandonment or deactivation of facilities. 192.727... Abandonment or deactivation of facilities. (a) Each operator shall conduct abandonment or deactivation of... commercially navigable waterway, the last operator of that facility must file a report upon abandonment of...

  12. 37 CFR 2.68 - Express abandonment (withdrawal) of application.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Express abandonment... Action by Applicants § 2.68 Express abandonment (withdrawal) of application. (a) Written document required. An applicant may expressly abandon an application by filing a written request for abandonment...

  13. 37 CFR 2.68 - Express abandonment (withdrawal) of application.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Express abandonment... Action by Applicants § 2.68 Express abandonment (withdrawal) of application. (a) Written document required. An applicant may expressly abandon an application by filing a written request for abandonment...

  14. 49 CFR 192.727 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 3 2014-10-01 2014-10-01 false Abandonment or deactivation of facilities. 192.727... Abandonment or deactivation of facilities. (a) Each operator shall conduct abandonment or deactivation of... commercially navigable waterway, the last operator of that facility must file a report upon abandonment of...

  15. 37 CFR 2.68 - Express abandonment (withdrawal) of application.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Express abandonment... Action by Applicants § 2.68 Express abandonment (withdrawal) of application. (a) Written document required. An applicant may expressly abandon an application by filing a written request for abandonment...

  16. 20 CFR 410.649 - Dismissal by abandonment of party.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Dismissal by abandonment of party. 410.649..., Administrative Review, Finality of Decisions, and Representation of Parties § 410.649 Dismissal by abandonment of... upon its abandonment by the party or parties who filed it. A party shall be deemed to have abandoned...

  17. 49 CFR 192.727 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 3 2012-10-01 2012-10-01 false Abandonment or deactivation of facilities. 192.727... Abandonment or deactivation of facilities. (a) Each operator shall conduct abandonment or deactivation of... commercially navigable waterway, the last operator of that facility must file a report upon abandonment of...

  18. 20 CFR 410.649 - Dismissal by abandonment of party.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Dismissal by abandonment of party. 410.649..., Administrative Review, Finality of Decisions, and Representation of Parties § 410.649 Dismissal by abandonment of... upon its abandonment by the party or parties who filed it. A party shall be deemed to have abandoned...

  19. 32 CFR 644.494 - Donation, abandonment or destruction.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 32 National Defense 4 2014-07-01 2013-07-01 true Donation, abandonment or destruction. 644.494... Land) § 644.494 Donation, abandonment or destruction. (a) General. Improvements may be abandoned... from its sale, or that abandonment or destruction is required by military necessity, or...

  20. 32 CFR 644.494 - Donation, abandonment or destruction.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Donation, abandonment or destruction. 644.494... Land) § 644.494 Donation, abandonment or destruction. (a) General. Improvements may be abandoned... from its sale, or that abandonment or destruction is required by military necessity, or...

  1. 37 CFR 2.68 - Express abandonment (withdrawal) of application.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Express abandonment... Action by Applicants § 2.68 Express abandonment (withdrawal) of application. (a) Written document required. An applicant may expressly abandon an application by filing a written request for abandonment...

  2. 32 CFR 644.494 - Donation, abandonment or destruction.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 32 National Defense 4 2012-07-01 2011-07-01 true Donation, abandonment or destruction. 644.494... Land) § 644.494 Donation, abandonment or destruction. (a) General. Improvements may be abandoned... from its sale, or that abandonment or destruction is required by military necessity, or...

  3. 32 CFR 644.494 - Donation, abandonment or destruction.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 32 National Defense 4 2013-07-01 2013-07-01 false Donation, abandonment or destruction. 644.494... Land) § 644.494 Donation, abandonment or destruction. (a) General. Improvements may be abandoned... from its sale, or that abandonment or destruction is required by military necessity, or...

  4. 49 CFR 192.727 - Abandonment or deactivation of facilities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 3 2013-10-01 2013-10-01 false Abandonment or deactivation of facilities. 192.727... Abandonment or deactivation of facilities. (a) Each operator shall conduct abandonment or deactivation of... commercially navigable waterway, the last operator of that facility must file a report upon abandonment of...

  5. The rail abandonment process: A southern perspective

    SciTech Connect

    Not Available

    1988-12-01

    One factor in evaluating the desirability of rail transport for high-level radioactive wastes or spent fuels is the frequency, or lack thereof, with which railroad and railroad lines have been, and are, abandoned. If DOE makes a decision to use the rail option and a line is subsequently abandoned, the choice results in increased cost, time delays and possibly safety problems: Information is therefore needed prior to the decision-making process to evaluate the desirability of the rail shipping option. One result of the abandonments mentioned herein, as well as other later abandonments, is the creation of a US rail system undergoing an evolutionary process in the 1980s as far-reaching as the changes that occurred when the industry was in its infancy a century and-a-half ago. The purpose of this paper is to examine the factors leading to some of these changes by tracing the historical development of the rail abandonment process, with particular emphasis on the rise of regional railroads, their problems in the modern era and current trends in rail abandonments as well as their effects on the southeastern United States.

  6. Assessing vulnerability in stream channel evolution in relation with morphological transformations and hydrodynamic behavior. Case Study: the Subcarpathian Prahova Valley, Romania

    NASA Astrophysics Data System (ADS)

    Osaci-Costache, G.; Armas, I.; Gogoase Nistoran, D.; Gheorghe, D.

    2010-05-01

    The objective of the study is to analyze the relationship between morphological transformations observed during the last 200 years along a 20 km reach of Prahova river, and hydrodynamic behavior during high intensity flood periods, in the context of erosion-control works and environmental changes. Along this sub-Carpathian reach, Prahova is a typical mountain river, partially regulated, flowing under fluvial and torrential regime and having a mean thalweg slope of about 1%. Riverbed material consists in cobbles and boulders. Its valley has gradually been cut; therefore four terraces may clearly be identified in the subbasin areas of Breaza and Câmpina. The Holocene floodplain is asymmetrical, and during the last decades an incision of about 3-4 m has clearly been observed in the main channel. This also led to an evolution from an anabranching river aspect to a meandering one along the studied reach. Reasons to explain these changes are a positive neotectonic background coupled with an increased anthropic component (granular material extraction, channel regulation for construction purposes of roads, bridges, railways, layout of gas and oil pipelines, vegetation cutoff etc.). The data obtained from 1900-1980 topographical maps and 1997-2002 satellite images and orthophotos were coupled with topo-bathymetric surveys carried out in 57 cross-sections, in order to obtain the DTM of the studied area. These cross-sections were used to build up the geometry of a 1D hydraulic model by using the HEC-RAS software (USACE, version 3.1.3). Simulations were obtained under steady flow conditions for 1% and 2% return periods (360-400 mc/s and 450-500 mc/s). Calibration of Manning roughness factors was performed on stages measured at the two upstream and downstream gauging stations. High values of computed shear stresses and velocities show areas of potential erosion leading to morphological changes, bank collapsing and incision observed during the last decades and predicted for the

  7. USING STREAM MORPHOLOGY CLASSIFICATION TO MANAGE ECOLOGICAL RISKS FROM LAND USE CHANGES IN THE LMR WATERSHED

    EPA Science Inventory

    Changes in the amount and types of land use in a watershed can destabilize stream channel structure, increase sediment loading and degrade in-stream habitat. Stream classification systems (e.g. Rosgen) may be useful for determining the susceptibility of stream channel segments t...

  8. USUING STREAM MORPHOLOGY CLASSIFICATION TO MANAGE ECOLOGICAL RISKS FROM LAND USE CHANGES IN THE LMR WATERSHED

    EPA Science Inventory

    Changes in the amount and types of land use in a watershed can destabilize stream channel structure, increase sediment loading and degrade in-stream habitat. Stream classification systems (e.g. Rosgen) may be useful for determining the susceptibility of stream channel segments t...

  9. Channel incision and water quality

    NASA Astrophysics Data System (ADS)

    Shields, F. D.

    2009-12-01

    Watershed development often triggers channel incision that leads to radical changes in channel morphology. Although morphologic evolution due to channel incision has been documented and modeled by others, ecological effects, particularly water quality effects, are less well understood. Furthermore, environmental regulatory frameworks for streams frequently focus on stream water quality and underemphasize hydrologic and geomorphic issues. Discharge, basic physical parameters, solids, nutrients (nitrogen and phosphorus), chlorophyll and bacteria were monitored for five years at two sites along a stream in a mixed cover watershed characterized by rapid incision of the entire channel network. Concurrent data were collected from two sites on a nearby stream draining a watershed of similar size and cultivation intensity, but without widespread incision. Data sets describing physical aquatic habitat and fish fauna of each stream were available from other studies. The second stream was impacted by watershed urbanization, but was not incised, so normal channel-floodplain interaction maintained a buffer zone of floodplain wetlands between the study reach and the urban development upstream. The incised stream had mean channel depth and width that were 1.8 and 3.5 times as large as for the nonincised stream, and was characterized by flashier hydrology. The median rise rate for the incised stream was 6.4 times as great as for the nonincised stream. Correlation analyses showed that hydrologic perturbations were associated with water quality degradation, and the incised stream had levels of turbidity and solids that were two to three times higher than the nonincised, urbanizing stream. Total phosphorus, total Kjeldahl N, and chlorophyll a concentrations were significantly higher in the incised stream, while nitrate was significantly greater in the nonincised, urbanizing stream (p < 0.02). Physical aquatic habitat and fish populations in the nonincised urbanizing stream were

  10. Analyzing indicators of stream health for Minnesota streams

    USGS Publications Warehouse

    Singh, U.; Kocian, M.; Wilson, B.; Bolton, A.; Nieber, J.; Vondracek, B.; Perry, J.; Magner, J.

    2005-01-01

    Recent research has emphasized the importance of using physical, chemical, and biological indicators of stream health for diagnosing impaired watersheds and their receiving water bodies. A multidisciplinary team at the University of Minnesota is carrying out research to develop a stream classification system for Total Maximum Daily Load (TMDL) assessment. Funding for this research is provided by the United States Environmental Protection Agency and the Minnesota Pollution Control Agency. One objective of the research study involves investigating the relationships between indicators of stream health and localized stream characteristics. Measured data from Minnesota streams collected by various government and non-government agencies and research institutions have been obtained for the research study. Innovative Geographic Information Systems tools developed by the Environmental Science Research Institute and the University of Texas are being utilized to combine and organize the data. Simple linear relationships between index of biological integrity (IBI) and channel slope, two-year stream flow, and drainage area are presented for the Redwood River and the Snake River Basins. Results suggest that more rigorous techniques are needed to successfully capture trends in IBI scores. Additional analyses will be done using multiple regression, principal component analysis, and clustering techniques. Uncovering key independent variables and understanding how they fit together to influence stream health are critical in the development of a stream classification for TMDL assessment.

  11. Geomorphic applications of stream-gage information

    USGS Publications Warehouse

    Juracek, K.E.; Fitzpatrick, F.A.

    2009-01-01

    In the United States, several thousand stream gages provide what typically is the only source of continuous, long-term streamflow and channel-geometry information for the locations being monitored. In this paper, the geomorphic content of stream-gage information, previous and potential applications of stream-gage information in fluvial geomorphic research and various possible limitations are described. Documented applications include studies of hydraulic geometry, channel bankfull characteristics, sediment transport and channel geomorphic response to various types of disturbance. Potential applications include studies to determine the geomorphic effectiveness of large floods and in-stream habitat change in response to disturbance. For certain applications, various spatial, temporal and data limitations may render the stream-gage information of limited use; however, such information often is of considerable value to enable or enhance geomorphic investigations.

  12. Effects of urbanization and urban stream restoration on the physical and biological structure of stream ecosystems.

    PubMed

    Violin, Christy R; Cada, Peter; Sudduth, Elizabeth B; Hassett, Brooke A; Penrose, David L; Bernhardt, Emily S

    2011-09-01

    Streams, as low-lying points in the landscape, are strongly influenced by the stormwaters, pollutants, and warming that characterize catchment urbanization. River restoration projects are an increasingly popular method for mitigating urban insults. Despite the growing frequency and high expense of urban stream restoration projects, very few projects have been evaluated to determine whether they can successfully enhance habitat structure or support the stream biota characteristic of reference sites. We compared the physical and biological structure of four urban degraded, four urban restored, and four forested streams in the Piedmont region of North Carolina to quantify the ability of reach-scale stream restoration to restore physical and biological structure to urban streams and to examine the assumption that providing habitat is sufficient for biological recovery. To be successful at mitigating urban impacts, the habitat structure and biological communities found in restored streams should be more similar to forested reference sites than to their urban degraded counterparts. For every measured reach- and patch-scale attribute, we found that restored streams were indistinguishable from their degraded urban stream counterparts. Forested streams were shallower, had greater habitat complexity and median sediment size, and contained less-tolerant communities with higher sensitive taxa richness than streams in either urban category. Because heavy machinery is used to regrade and reconfigure restored channels, restored streams had less canopy cover than either forested or urban streams. Channel habitat complexity and watershed impervious surface cover (ISC) were the best predictors of sensitive taxa richness and biotic index at the reach and catchment scale, respectively. Macroinvertebrate communities in restored channels were compositionally similar to the communities in urban degraded channels, and both were dissimilar to communities in forested streams. The

  13. Stream Centerline for Fanno Creek, Oregon

    USGS Publications Warehouse

    Sobieszczyk, Steven

    2011-01-01

    Fanno Creek is a tributary to the Tualatin River and flows though parts of the southwest Portland metropolitan area. The stream is heavily influenced by urban runoff and shows characteristic flashy streamflow and poor water quality commonly associated with urban streams. This data set represents the stream centerline of the current active channel as derived from light detection and ranging (LiDAR) data and aerial photographic imagery.

  14. Stream salamanders as indicators of stream quality in Maryland, USA

    USGS Publications Warehouse

    Southerland, M.T.; Jung, R.E.; Baxter, D.P.; Chellman, I.C.; Mercurio, G.; Volstad, J.H.

    2004-01-01

    Biological indicators are critical to the protection of small, headwater streams and the ecological values they provide. Maryland and other state monitoring programs have determined that fish indicators are ineffective in small streams, where stream salamanders may replace fish as top predators. Because of their life history, physiology, abundance, and ubiquity, stream salamanders are likely representative of biological integrity in these streams. The goal of this study was to determine whether stream salamanders are effective indicators of ecological conditions across biogeographic regions and gradients of human disturbance. During the summers of 2001 and 2002, we intensively surveyed for stream salamanders at 76 stream sites located west of the Maryland Coastal Plain, sites also monitored by the Maryland Biological Stream Survey (MBSS) and City of Gaithersburg. We found 1,584 stream salamanders, including all eight species known in Maryland, using two 15 ? 2 m transects and two 4 m2 quadrats that spanned both stream bank and channel. We performed removal sampling on transects to estimate salamander species detection probabilities, which ranged from 0.67-0.85. Stepwise regressions identified 15 of 52 non-salamander variables, representing water quality, physical habitat, land use, and biological conditions, which best predicted salamander metrics. Indicator development involved (1) identifying reference (non-degraded) and degraded sites (using percent forest, shading, riparian buffer width, aesthetic rating, and benthic macroinvertebrate and fish indices of biotic integrity); (2) testing 12 candidate salamander metrics (representing species richness and composition, abundance, species tolerance, and reproductive function) for their ability to distinguish reference from degraded sites; and (3) combining metrics into an index that effectively discriminated sites according to known stream conditions. Final indices for Highlands, Piedmont, and Non-Coastal Plain

  15. Infanticide and illegal infant abandonment in Malaysia.

    PubMed

    Razali, Salmi; Kirkman, Maggie; Ahmad, S Hassan; Fisher, Jane

    2014-10-01

    Infant abandonment and infanticide are poorly understood in Malaysia. The information available in the public arena comes predominantly from anecdotal sources. The aim of this study was to describe the prevalence and characteristics of infanticide and illegal infant abandonment in Malaysia and to estimate annual rates for the most recent decade. Summaries of data about infanticide and illegal infant abandonment were gathered from police records; the annual number of live births was ascertained from the national registry. The estimated inferred infanticide rates for Malaysia were compared with the infanticide rates among countries of very high, high, medium, and low rankings on the Human Development, Gender Inequality, and Gini indices. From 1999 to 2011, 1,069 cases of illegal infant abandonment were recorded and 1,147 people were arrested as suspected perpetrators. The estimated inferred infanticide rate fluctuated between 4.82 and 9.11 per 100,000 live births, a moderate rate relative to the infanticide rates of other countries. There are substantial missing data, with details undocumented for about 78-87% of cases and suspected perpetrators. Of the documented cases, it appeared that more boys than girls were victims and that suspected perpetrators were predominantly Malays who were women, usually mothers of the victim; the possibility of arrest bias must be acknowledged. Economic and social inequality, particularly gender inequality, might contribute to the phenomena of infanticide and abandonment. Strategies to reduce rates of infanticide and illegal infant abandonment in Malaysia will require strengthening of the surveillance system and attention to the gender-based inequalities that underpin human development.

  16. Multiphase Flow and Cavern Abandonment in Salt

    SciTech Connect

    Ehgartner, Brian; Tidwell, Vince

    2001-02-13

    This report will explore the hypothesis that an underground cavity in gassy salt will eventually be gas filled as is observed on a small scale in some naturally occurring salt inclusions. First, a summary is presented on what is known about gas occurrences, flow mechanisms, and cavern behavior after abandonment. Then, background information is synthesized into theory on how gas can fill a cavern and simultaneously displace cavern fluids into the surrounding salt. Lastly, two-phase (gas and brine) flow visualization experiments are presented that demonstrate some of the associated flow mechanisms and support the theory and hypothesis that a cavity in salt can become gas filled after plugging and abandonment

  17. Stream Studies.

    ERIC Educational Resources Information Center

    Hamilton City Board of Education (Ontario).

    This manual provides teachers with some knowledge of ecological study methods and techniques used in collecting data when plants and animals are studied in the field. Most activities deal with the interrelatedness of plant and animal life to the structure and characteristics of a stream and pond. Also included in this unit plan designed for the…

  18. Stream Studies.

    ERIC Educational Resources Information Center

    Stein, Scott

    1997-01-01

    Outlines a science curriculum reform effort aimed at enabling students to collect original data concerning an environmental parameter such as water quality on a yearly basis. Students track the overall health of the stream by analyzing both biotic and abiotic factors. (DDR)

  19. Ecoregions and stream morphology in eastern Oklahoma

    USGS Publications Warehouse

    Splinter, D.K.; Dauwalter, D.C.; Marston, R.A.; Fisher, W.L.

    2010-01-01

    Broad-scale variables (i.e., geology, topography, climate, land use, vegetation, and soils) influence channel morphology. How and to what extent the longitudinal pattern of channel morphology is influenced by broad-scale variables is important to fluvial geomorphologists and stream ecologists. In the last couple of decades, there has been an increase in the amount of interdisciplinary research between fluvial geomorphologists and stream ecologists. In a historical context, fluvial geomorphologists are more apt to use physiographic regions to distinguish broad-scale variables, while stream ecologists are more apt to use the concept of an ecosystem to address the broad-scale variables that influence stream habitat. For this reason, we designed a study using ecoregions, which uses physical and biological variables to understand how landscapes influence channel processes. Ecoregions are delineated by similarities in geology, climate, soils, land use, and potential natural vegetation. In the fluvial system, stream form and function are dictated by processes observed throughout the fluvial hierarchy. Recognizing that stream form and function should differ by ecoregion, a study was designed to evaluate how the characteristics of stream channels differed longitudinally among three ecoregions in eastern Oklahoma, USA: Boston Mountains, Ozark Highlands, and Ouachita Mountains. Channel morphology of 149 stream reaches was surveyed in 1st- through 4th-order streams, and effects of drainage area and ecoregion on channel morphology was evaluated using multiple regressions. Differences existed (?????0.05) among ecoregions for particle size, bankfull width, and width/depth ratio. No differences existed among ecoregions for gradient or sinuosity. Particle size was smallest in the Ozark Highlands and largest in the Ouachita Mountains. Bankfull width was larger in the Ozark Highlands than in the Boston Mountains and Ouachita Mountains in larger streams. Width/depth ratios of the

  20. Macrophyte presence is an indicator of enhanced denitrification and nitrification in sediments of a temperate restored agricultural stream

    EPA Science Inventory

    Stream macrophytes are often removed with their sediments to deepen stream channels, stabilize channel banks, or provide habitat for target species. These sediments may support enhanced nitrogen processing. To evaluate sediment nitrogen processing, identify seasonal patterns, and...

  1. 4. INTERIOR OF ABANDONED SANTA ANA CANAL TUNNEL, SHOWING CEMENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. INTERIOR OF ABANDONED SANTA ANA CANAL TUNNEL, SHOWING CEMENT TROUGH FLOOR AND UNFINISHED GRANITE ROOF. VIEW TO SOUTHWEST. - Santa Ana River Hydroelectric System, Abandoned Tunnel, Redlands, San Bernardino County, CA

  2. Reclamation of abandoned mined lands in India

    SciTech Connect

    Aufmuth, R.E.

    1986-01-01

    An international approach to developing a conceptual environmental management plan for the reclamation of abandoned coal mined lands in India will be discussed. This plan will be aimed at reclamation of a coal field which has been mined for almost 100 years with no reclamation of any kind.

  3. Reclamation of abandoned mines in West Virginia

    SciTech Connect

    Dove, J.L.

    1983-01-01

    Reclamation of abandoned mine lands in West Virginia involves disturbed areas from both surface and deep mining activities. Reclamation of deep mine lands deal with mine waste piles and mine openings. Reclamation of surface mine lands involves shaping and grading material to obtain a stable slope and installing water management practices.

  4. 19 CFR 147.47 - Mandatory abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Mandatory abandonment. 147.47 Section 147.47 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.47 Mandatory...

  5. 19 CFR 147.47 - Mandatory abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 2 2011-04-01 2011-04-01 false Mandatory abandonment. 147.47 Section 147.47 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.47 Mandatory...

  6. 19 CFR 147.47 - Mandatory abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 2 2013-04-01 2013-04-01 false Mandatory abandonment. 147.47 Section 147.47 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.47 Mandatory...

  7. 19 CFR 147.47 - Mandatory abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 2 2014-04-01 2014-04-01 false Mandatory abandonment. 147.47 Section 147.47 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.47 Mandatory...

  8. 19 CFR 147.47 - Mandatory abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 2 2012-04-01 2012-04-01 false Mandatory abandonment. 147.47 Section 147.47 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE TREASURY (CONTINUED) TRADE FAIRS Disposition of Articles Entered for Fairs § 147.47 Mandatory...

  9. 23 CFR 752.10 - Abandoned vehicles.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 23 Highways 1 2014-04-01 2014-04-01 false Abandoned vehicles. 752.10 Section 752.10 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RIGHT-OF-WAY AND ENVIRONMENT LANDSCAPE AND..., or enhancement of scenic beauty as seen from the traveled way of the highway as a landscape...

  10. 23 CFR 752.10 - Abandoned vehicles.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Abandoned vehicles. 752.10 Section 752.10 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RIGHT-OF-WAY AND ENVIRONMENT LANDSCAPE AND..., or enhancement of scenic beauty as seen from the traveled way of the highway as a landscape...

  11. 23 CFR 752.10 - Abandoned vehicles.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Abandoned vehicles. 752.10 Section 752.10 Highways FEDERAL HIGHWAY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION RIGHT-OF-WAY AND ENVIRONMENT LANDSCAPE AND..., or enhancement of scenic beauty as seen from the traveled way of the highway as a landscape...

  12. 32 CFR 636.31 - Abandoned vehicles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... § 636.31 Abandoned vehicles. (a) Any MP or DOD police officer who finds or has knowledge of a motor... MP or DOD police officer who, under the provisions of this section, causes any motor vehicle to be... motor vehicle by any MP or DOD police officer should not be within the scope of either that...

  13. Effects of urban stream burial on nitrogen uptake and ecosystem metabolism: implications for watershed nitrogen and carbon fluxes

    EPA Science Inventory

    Urbanization has resulted in extensive burial and channelization of headwater streams, yet little is known about impacts on stream ecosystem functions critical for reducing downstream nitrogen pollution. To characterize the biogeochemical impact of stream burial, we measured NO3...

  14. Biogeochemistry and Hydrology in Streams Impacted by Legacy Sediments and Urbanization: Implications for Stream Restoration

    EPA Science Inventory

    The groundwater–surface water interface, consisting of shallow groundwater adjacent to stream channels, is a hot spot for nitrogen removal processes, a storage zone for other solutes, and a target for restoration activities. Characterizing groundwater-surface water interac...

  15. The burial of headwater streams in drainage pipes reduces in-stream nitrate retention: results from two US metropolitan areas

    EPA Science Inventory

    Nitrogen (N) retention in stream networks is an important ecosystem service that may be affected by the widespread burial of headwater streams in urban watersheds. Stream burial occurs when segments of a channel are encased in drainage pipe and buried beneath the land surface to...

  16. Working Models about Mother-Child Relationships in Abandoned Children.

    ERIC Educational Resources Information Center

    Garcia-Torres, Belen; Guerrero, Pilar Garcia-Calvo

    2000-01-01

    Sixty abandoned and 36 non-abandoned school-aged children were told six short stories about mother-child relationships. Abandoned children showed less positive affect attribution to the mother, more compliant behavior in the child, and more justification of the mother when her behaviors were unfair. (Contains references.) (Author/CR)

  17. 30 CFR 900.14 - Abandoned mine land programs.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 3 2014-07-01 2014-07-01 false Abandoned mine land programs. 900.14 Section 900.14 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE... Abandoned mine land programs. Programs for reclamation of abandoned mine lands are codified under...

  18. 30 CFR 900.14 - Abandoned mine land programs.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 3 2013-07-01 2013-07-01 false Abandoned mine land programs. 900.14 Section 900.14 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE... Abandoned mine land programs. Programs for reclamation of abandoned mine lands are codified under...

  19. 30 CFR 900.14 - Abandoned mine land programs.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 3 2011-07-01 2011-07-01 false Abandoned mine land programs. 900.14 Section 900.14 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE... Abandoned mine land programs. Programs for reclamation of abandoned mine lands are codified under...

  20. 30 CFR 900.14 - Abandoned mine land programs.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Abandoned mine land programs. 900.14 Section 900.14 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE... Abandoned mine land programs. Programs for reclamation of abandoned mine lands are codified under...

  1. 40 CFR 147.3102 - Plugging and abandonment plans.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Plugging and abandonment plans. 147... Certain Oklahoma Indian Tribes § 147.3102 Plugging and abandonment plans. In lieu of the requirements of... with the plugging and abandonment provisions of § 147.3108 of this subpart....

  2. 15 CFR 904.508 - Voluntary forfeiture by abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 15 Commerce and Foreign Trade 3 2010-01-01 2010-01-01 false Voluntary forfeiture by abandonment... PROCEDURES Seizure and Forfeiture Procedures § 904.508 Voluntary forfeiture by abandonment. (a) The owner of... to NOAA. Voluntary forfeiture by abandonment under this section may be accomplished by various...

  3. 37 CFR 2.135 - Abandonment of application or mark.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Abandonment of application or... Abandonment of application or mark. After the commencement of an opposition, concurrent use, or interference proceeding, if the applicant files a written abandonment of the application or of the mark without...

  4. 30 CFR 57.22223 - Crosscuts before abandonment (III mines).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Crosscuts before abandonment (III mines). 57.22223 Section 57.22223 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... abandonment (III mines). A means of ventilating faces shall be provided before workings are abandoned...

  5. 43 CFR 3162.3-4 - Well abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... officer. All costs over and above the normal plugging and abandonment expense will be paid by the...

  6. 30 CFR 57.22223 - Crosscuts before abandonment (III mines).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Crosscuts before abandonment (III mines). 57.22223 Section 57.22223 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... abandonment (III mines). A means of ventilating faces shall be provided before workings are abandoned...

  7. 40 CFR 147.3102 - Plugging and abandonment plans.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Plugging and abandonment plans. 147... Certain Oklahoma Indian Tribes § 147.3102 Plugging and abandonment plans. In lieu of the requirements of... with the plugging and abandonment provisions of § 147.3108 of this subpart....

  8. 50 CFR 27.93 - Abandonment of property.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Abandonment of property. 27.93 Section 27.93 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Abandonment of property. Abandoning, discarding, or otherwise leaving any personal property in any...

  9. 21 CFR 1303.27 - Abandonment of quota.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 9 2011-04-01 2011-04-01 false Abandonment of quota. 1303.27 Section 1303.27 Food... Quotas § 1303.27 Abandonment of quota. Any manufacturer assigned an individual manufacturing quota for... abandonment, stating the name and Administration Controlled Substances Code Number, as set forth in part...

  10. 30 CFR 256.56 - Lease-specific abandonment accounts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false Lease-specific abandonment accounts. 256.56... OF SULPHUR OR OIL AND GAS IN THE OUTER CONTINENTAL SHELF Bonding § 256.56 Lease-specific abandonment accounts. (a) The Regional Director may authorize you to establish a lease-specific abandonment account...

  11. 21 CFR 1303.27 - Abandonment of quota.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 9 2012-04-01 2012-04-01 false Abandonment of quota. 1303.27 Section 1303.27 Food... Quotas § 1303.27 Abandonment of quota. Any manufacturer assigned an individual manufacturing quota for... abandonment, stating the name and Administration Controlled Substances Code Number, as set forth in part...

  12. 15 CFR 904.508 - Voluntary forfeiture by abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 15 Commerce and Foreign Trade 3 2013-01-01 2013-01-01 false Voluntary forfeiture by abandonment... PROCEDURES Seizure and Forfeiture Procedures § 904.508 Voluntary forfeiture by abandonment. (a) The owner of... to NOAA. Voluntary forfeiture by abandonment under this section may be accomplished by various...

  13. 50 CFR 27.93 - Abandonment of property.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 50 Wildlife and Fisheries 9 2014-10-01 2014-10-01 false Abandonment of property. 27.93 Section 27.93 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Abandonment of property. Abandoning, discarding, or otherwise leaving any personal property in any...

  14. 20 CFR 802.402 - Dismissal by abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 20 Employees' Benefits 4 2012-04-01 2012-04-01 false Dismissal by abandonment. 802.402 Section 802... Completion of Board Review Dismissals § 802.402 Dismissal by abandonment. (a) Upon motion by any party or representative or upon the Board's own motion, an appeal may be dismissed upon its abandonment by the party...

  15. 37 CFR 2.135 - Abandonment of application or mark.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2013-07-01 2013-07-01 false Abandonment of application or... Abandonment of application or mark. After the commencement of an opposition, concurrent use, or interference proceeding, if the applicant files a written abandonment of the application or of the mark without...

  16. 40 CFR 147.3102 - Plugging and abandonment plans.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Plugging and abandonment plans. 147... Certain Oklahoma Indian Tribes § 147.3102 Plugging and abandonment plans. In lieu of the requirements of... with the plugging and abandonment provisions of § 147.3108 of this subpart....

  17. 15 CFR 904.508 - Voluntary forfeiture by abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 15 Commerce and Foreign Trade 3 2011-01-01 2011-01-01 false Voluntary forfeiture by abandonment... PROCEDURES Seizure and Forfeiture Procedures § 904.508 Voluntary forfeiture by abandonment. (a) The owner of... to NOAA. Voluntary forfeiture by abandonment under this section may be accomplished by various...

  18. 20 CFR 802.402 - Dismissal by abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 20 Employees' Benefits 4 2014-04-01 2014-04-01 false Dismissal by abandonment. 802.402 Section 802... Completion of Board Review Dismissals § 802.402 Dismissal by abandonment. (a) Upon motion by any party or representative or upon the Board's own motion, an appeal may be dismissed upon its abandonment by the party...

  19. 19 CFR 12.126 - Notice of abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 19 Customs Duties 1 2013-04-01 2013-04-01 false Notice of abandonment. 12.126 Section 12.126 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE... § 12.126 Notice of abandonment. If the importer intends to abandon the shipment after receiving...

  20. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 25 Indians 1 2013-04-01 2013-04-01 false Prospecting; abandonment of mines. 214.29 Section 214.29... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of...

  1. 50 CFR 27.93 - Abandonment of property.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 50 Wildlife and Fisheries 9 2013-10-01 2013-10-01 false Abandonment of property. 27.93 Section 27.93 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Abandonment of property. Abandoning, discarding, or otherwise leaving any personal property in any...

  2. 36 CFR 14.30 - Nonconstruction, abandonment or nonuse.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 1 2012-07-01 2012-07-01 false Nonconstruction, abandonment... OF THE INTERIOR RIGHTS-OF-WAY Procedures § 14.30 Nonconstruction, abandonment or nonuse. Unless... to construct within the period allowed and for abandonment or nonuse....

  3. 19 CFR 12.126 - Notice of abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 19 Customs Duties 1 2011-04-01 2011-04-01 false Notice of abandonment. 12.126 Section 12.126 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE... § 12.126 Notice of abandonment. If the importer intends to abandon the shipment after receiving...

  4. 21 CFR 1303.27 - Abandonment of quota.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 9 2010-04-01 2010-04-01 false Abandonment of quota. 1303.27 Section 1303.27 Food... Quotas § 1303.27 Abandonment of quota. Any manufacturer assigned an individual manufacturing quota for... abandonment, stating the name and Administration Controlled Substances Code Number, as set forth in part...

  5. 20 CFR 802.402 - Dismissal by abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 20 Employees' Benefits 3 2011-04-01 2011-04-01 false Dismissal by abandonment. 802.402 Section 802... Completion of Board Review Dismissals § 802.402 Dismissal by abandonment. (a) Upon motion by any party or representative or upon the Board's own motion, an appeal may be dismissed upon its abandonment by the party...

  6. 43 CFR 3162.3-4 - Well abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... officer. All costs over and above the normal plugging and abandonment expense will be paid by the...

  7. 20 CFR 802.402 - Dismissal by abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 20 Employees' Benefits 4 2013-04-01 2013-04-01 false Dismissal by abandonment. 802.402 Section 802... Completion of Board Review Dismissals § 802.402 Dismissal by abandonment. (a) Upon motion by any party or representative or upon the Board's own motion, an appeal may be dismissed upon its abandonment by the party...

  8. 15 CFR 904.508 - Voluntary forfeiture by abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 15 Commerce and Foreign Trade 3 2014-01-01 2014-01-01 false Voluntary forfeiture by abandonment... PROCEDURES Seizure and Forfeiture Procedures § 904.508 Voluntary forfeiture by abandonment. (a) The owner of... to NOAA. Voluntary forfeiture by abandonment under this section may be accomplished by various...

  9. 36 CFR 14.30 - Nonconstruction, abandonment or nonuse.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 1 2011-07-01 2011-07-01 false Nonconstruction, abandonment... OF THE INTERIOR RIGHTS-OF-WAY Procedures § 14.30 Nonconstruction, abandonment or nonuse. Unless... to construct within the period allowed and for abandonment or nonuse....

  10. 50 CFR 27.93 - Abandonment of property.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 50 Wildlife and Fisheries 9 2012-10-01 2012-10-01 false Abandonment of property. 27.93 Section 27.93 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Abandonment of property. Abandoning, discarding, or otherwise leaving any personal property in any...

  11. 30 CFR 256.56 - Lease-specific abandonment accounts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Lease-specific abandonment accounts. 256.56... § 256.56 Lease-specific abandonment accounts. (a) The Regional Director may authorize you to establish a lease-specific abandonment account in a federally insured institution in lieu of the bond required...

  12. 36 CFR 14.30 - Nonconstruction, abandonment or nonuse.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 1 2014-07-01 2014-07-01 false Nonconstruction, abandonment... OF THE INTERIOR RIGHTS-OF-WAY Procedures § 14.30 Nonconstruction, abandonment or nonuse. Unless... to construct within the period allowed and for abandonment or nonuse....

  13. 50 CFR 27.93 - Abandonment of property.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 50 Wildlife and Fisheries 8 2011-10-01 2011-10-01 false Abandonment of property. 27.93 Section 27.93 Wildlife and Fisheries UNITED STATES FISH AND WILDLIFE SERVICE, DEPARTMENT OF THE INTERIOR... Abandonment of property. Abandoning, discarding, or otherwise leaving any personal property in any...

  14. 19 CFR 12.126 - Notice of abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 1 2010-04-01 2010-04-01 false Notice of abandonment. 12.126 Section 12.126 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE... § 12.126 Notice of abandonment. If the importer intends to abandon the shipment after receiving...

  15. 37 CFR 2.135 - Abandonment of application or mark.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2011-07-01 2011-07-01 false Abandonment of application or... Abandonment of application or mark. After the commencement of an opposition, concurrent use, or interference proceeding, if the applicant files a written abandonment of the application or of the mark without...

  16. 37 CFR 2.135 - Abandonment of application or mark.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2012-07-01 2012-07-01 false Abandonment of application or... Abandonment of application or mark. After the commencement of an opposition, concurrent use, or interference proceeding, if the applicant files a written abandonment of the application or of the mark without...

  17. 36 CFR 14.30 - Nonconstruction, abandonment or nonuse.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Nonconstruction, abandonment... OF THE INTERIOR RIGHTS-OF-WAY Procedures § 14.30 Nonconstruction, abandonment or nonuse. Unless... to construct within the period allowed and for abandonment or nonuse....

  18. 43 CFR 3162.3-4 - Well abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... officer. All costs over and above the normal plugging and abandonment expense will be paid by the...

  19. 37 CFR 2.135 - Abandonment of application or mark.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2014-07-01 2014-07-01 false Abandonment of application or... Abandonment of application or mark. After the commencement of an opposition, concurrent use, or interference proceeding, if the applicant files a written abandonment of the application or of the mark without...

  20. 40 CFR 147.3102 - Plugging and abandonment plans.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Plugging and abandonment plans. 147... Certain Oklahoma Indian Tribes § 147.3102 Plugging and abandonment plans. In lieu of the requirements of... with the plugging and abandonment provisions of § 147.3108 of this subpart....

  1. 15 CFR 904.508 - Voluntary forfeiture by abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 15 Commerce and Foreign Trade 3 2012-01-01 2012-01-01 false Voluntary forfeiture by abandonment... PROCEDURES Seizure and Forfeiture Procedures § 904.508 Voluntary forfeiture by abandonment. (a) The owner of... to NOAA. Voluntary forfeiture by abandonment under this section may be accomplished by various...

  2. 40 CFR 147.3102 - Plugging and abandonment plans.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Plugging and abandonment plans. 147... Certain Oklahoma Indian Tribes § 147.3102 Plugging and abandonment plans. In lieu of the requirements of... with the plugging and abandonment provisions of § 147.3108 of this subpart....

  3. 42 CFR 422.1060 - Dismissal for abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Dismissal for abandonment. 422.1060 Section 422.1060 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES....1060 Dismissal for abandonment. (a) The ALJ may dismiss a request for hearing if it is abandoned by...

  4. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 25 Indians 1 2012-04-01 2011-04-01 true Prospecting; abandonment of mines. 214.29 Section 214.29... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of...

  5. 43 CFR 3162.3-4 - Well abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... officer. All costs over and above the normal plugging and abandonment expense will be paid by the...

  6. 36 CFR 14.30 - Nonconstruction, abandonment or nonuse.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 1 2013-07-01 2013-07-01 false Nonconstruction, abandonment... OF THE INTERIOR RIGHTS-OF-WAY Procedures § 14.30 Nonconstruction, abandonment or nonuse. Unless... to construct within the period allowed and for abandonment or nonuse....

  7. 21 CFR 1303.27 - Abandonment of quota.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 9 2013-04-01 2013-04-01 false Abandonment of quota. 1303.27 Section 1303.27 Food... Quotas § 1303.27 Abandonment of quota. Any manufacturer assigned an individual manufacturing quota for... abandonment, stating the name and Administration Controlled Substances Code Number, as set forth in part...

  8. 30 CFR 57.22223 - Crosscuts before abandonment (III mines).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Crosscuts before abandonment (III mines). 57.22223 Section 57.22223 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... abandonment (III mines). A means of ventilating faces shall be provided before workings are abandoned...

  9. 20 CFR 802.402 - Dismissal by abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Dismissal by abandonment. 802.402 Section 802... Completion of Board Review Dismissals § 802.402 Dismissal by abandonment. (a) Upon motion by any party or representative or upon the Board's own motion, an appeal may be dismissed upon its abandonment by the party...

  10. 42 CFR 422.1060 - Dismissal for abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Dismissal for abandonment. 422.1060 Section 422.1060 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES....1060 Dismissal for abandonment. (a) The ALJ may dismiss a request for hearing if it is abandoned by...

  11. 30 CFR 57.22223 - Crosscuts before abandonment (III mines).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Crosscuts before abandonment (III mines). 57.22223 Section 57.22223 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... abandonment (III mines). A means of ventilating faces shall be provided before workings are abandoned...

  12. 21 CFR 1303.27 - Abandonment of quota.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 9 2014-04-01 2014-04-01 false Abandonment of quota. 1303.27 Section 1303.27 Food... Quotas § 1303.27 Abandonment of quota. Any manufacturer assigned an individual manufacturing quota for... abandonment, stating the name and Administration Controlled Substances Code Number, as set forth in part...

  13. 19 CFR 12.126 - Notice of abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 19 Customs Duties 1 2014-04-01 2014-04-01 false Notice of abandonment. 12.126 Section 12.126 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE... § 12.126 Notice of abandonment. If the importer intends to abandon the shipment after receiving...

  14. 30 CFR 57.22223 - Crosscuts before abandonment (III mines).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Crosscuts before abandonment (III mines). 57.22223 Section 57.22223 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... abandonment (III mines). A means of ventilating faces shall be provided before workings are abandoned...

  15. 19 CFR 12.126 - Notice of abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 19 Customs Duties 1 2012-04-01 2012-04-01 false Notice of abandonment. 12.126 Section 12.126 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY; DEPARTMENT OF THE... § 12.126 Notice of abandonment. If the importer intends to abandon the shipment after receiving...

  16. 39 CFR 946.11 - Disposition of property declared abandoned.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... DISPOSITION OF STOLEN MAIL MATTER AND PROPERTY ACQUIRED BY THE POSTAL INSPECTION SERVICE FOR USE AS EVIDENCE § 946.11 Disposition of property declared abandoned. Property declared abandoned, including cash, and... 39 Postal Service 1 2012-07-01 2012-07-01 false Disposition of property declared abandoned....

  17. 39 CFR 946.11 - Disposition of property declared abandoned.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... DISPOSITION OF STOLEN MAIL MATTER AND PROPERTY ACQUIRED BY THE POSTAL INSPECTION SERVICE FOR USE AS EVIDENCE § 946.11 Disposition of property declared abandoned. Property declared abandoned, including cash, and... 39 Postal Service 1 2014-07-01 2014-07-01 false Disposition of property declared abandoned....

  18. 39 CFR 946.11 - Disposition of property declared abandoned.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... DISPOSITION OF STOLEN MAIL MATTER AND PROPERTY ACQUIRED BY THE POSTAL INSPECTION SERVICE FOR USE AS EVIDENCE § 946.11 Disposition of property declared abandoned. Property declared abandoned, including cash, and... 39 Postal Service 1 2013-07-01 2013-07-01 false Disposition of property declared abandoned....

  19. 30 CFR 57.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Abandoned electric circuits. 57.4011 Section 57.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... and Control § 57.4011 Abandoned electric circuits. Abandoned electric circuits shall be...

  20. 30 CFR 56.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Abandoned electric circuits. 56.4011 Section 56.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Control § 56.4011 Abandoned electric circuits. Abandoned electric circuits shall be deenergized...

  1. 30 CFR 57.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Abandoned electric circuits. 57.4011 Section 57.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... and Control § 57.4011 Abandoned electric circuits. Abandoned electric circuits shall be...

  2. 30 CFR 56.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Abandoned electric circuits. 56.4011 Section 56.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Control § 56.4011 Abandoned electric circuits. Abandoned electric circuits shall be deenergized...

  3. 30 CFR 56.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Abandoned electric circuits. 56.4011 Section 56.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Control § 56.4011 Abandoned electric circuits. Abandoned electric circuits shall be deenergized...

  4. 30 CFR 56.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Abandoned electric circuits. 56.4011 Section 56.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Control § 56.4011 Abandoned electric circuits. Abandoned electric circuits shall be deenergized...

  5. 30 CFR 57.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Abandoned electric circuits. 57.4011 Section 57.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... and Control § 57.4011 Abandoned electric circuits. Abandoned electric circuits shall be...

  6. 30 CFR 57.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Abandoned electric circuits. 57.4011 Section 57.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... and Control § 57.4011 Abandoned electric circuits. Abandoned electric circuits shall be...

  7. Non-Abandonment as a Foundation for Inclusive School Practice

    ERIC Educational Resources Information Center

    Razer, Michal; Friedman, Victor J.

    2013-01-01

    The authors of this article describe an essential feature of inclusive educational practice: "non-abandonment". When students' needs and difficult behavior are overwhelming, teachers may abandon them emotionally as a defensive reaction to their own experience of emotional distress and helplessness. Non-abandonment represents a…

  8. 30 CFR 57.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Abandoned electric circuits. 57.4011 Section 57.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... and Control § 57.4011 Abandoned electric circuits. Abandoned electric circuits shall be...

  9. 30 CFR 56.4011 - Abandoned electric circuits.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Abandoned electric circuits. 56.4011 Section 56.4011 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL... Control § 56.4011 Abandoned electric circuits. Abandoned electric circuits shall be deenergized...

  10. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of the... 25 Indians 1 2014-04-01 2014-04-01 false Prospecting; abandonment of mines. 214.29 Section...

  11. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of the... 25 Indians 1 2011-04-01 2011-04-01 false Prospecting; abandonment of mines. 214.29 Section...

  12. 25 CFR 214.29 - Prospecting; abandonment of mines.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... RESERVATION LANDS, OKLAHOMA, FOR MINING, EXCEPT OIL AND GAS § 214.29 Prospecting; abandonment of mines. All prospecting or mining operations or the abandonment of a well or mine shall be subject to the approval of the... 25 Indians 1 2010-04-01 2010-04-01 false Prospecting; abandonment of mines. 214.29 Section...

  13. 30 CFR 900.14 - Abandoned mine land programs.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 3 2012-07-01 2012-07-01 false Abandoned mine land programs. 900.14 Section 900.14 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE... Abandoned mine land programs. Programs for reclamation of abandoned mine lands are codified under...

  14. Global perspectives on the urban stream syndrome

    USGS Publications Warehouse

    Roy, Allison; Booth, Derek B.; Capps, Krista A.; Smith, Benjamin

    2016-01-01

    Urban streams commonly express degraded physical, chemical, and biological conditions that have been collectively termed the “urban stream syndrome”. The description of the syndrome highlights the broad similarities among these streams relative to their less-impaired counterparts. Awareness of these commonalities has fostered rapid improvements in the management of urban stormwater for the protection of downstream watercourses, but the focus on the similarities among urban streams has obscured meaningful differences among them. Key drivers of stream responses to urbanization can vary greatly among climatological and physiographic regions of the globe, and the differences can be manifested in individual stream channels even through the homogenizing veneer of urban development. We provide examples of differences in natural hydrologic and geologic settings (within similar regions) that can result in different mechanisms of stream ecosystem response to urbanization and, as such, should lead to different management approaches. The idea that all urban streams can be cured using the same treatment is simplistic, but overemphasizing the tremendous differences among natural (or human-altered) systems also can paralyze management. Thoughtful integration of work that recognizes the commonalities of the urban stream syndrome across the globe has benefitted urban stream management. Now we call for a more nuanced understanding of the regional, subregional, and local attributes of any given urban stream and its watershed to advance the physical, chemical, and ecological recovery of these systems.

  15. Explosives remain preferred methods for platform abandonment

    SciTech Connect

    Pulsipher, A.; Daniel, W. IV; Kiesler, J.E.; Mackey, V. III

    1996-05-06

    Economics and safety concerns indicate that methods involving explosives remain the most practical and cost-effective means for abandoning oil and gas structures in the Gulf of Mexico. A decade has passed since 51 dead sea turtles, many endangered Kemp`s Ridleys, washed ashore on the Texas coast shortly after explosives helped remove several offshore platforms. Although no relationship between the explosions and the dead turtles was ever established, in response to widespread public concern, the US Minerals Management Service (MMS) and National Marine Fisheries Service (NMFS) implemented regulations limiting the size and timing of explosive charges. Also, more importantly, they required that operators pay for observers to survey waters surrounding platforms scheduled for removal for 48 hr before any detonations. If observers spot sea turtles or marine mammals within the danger zone, the platform abandonment is delayed until the turtles leave or are removed. However, concern about the effects of explosives on marine life remains.

  16. 75 years after mining ends stream insect diversity is still affected by heavy metals.

    PubMed

    Lefcort, Hugh; Vancura, James; Lider, Edward L

    2010-11-01

    A century of heavy metal mining in the western United States has left a legacy of abandoned mines. While large operations have left a visible reminder, smaller one and two-man operations have been overgrown and largely forgotten. We revisited an area of northern Idaho that has not had active mining since at least 1932 and probably since 1910. At three sites along each of 10 mountain streams we sampled larval stream insects and correlated their community diversity to stream levels of arsenic, cadmium, lead, zinc, pH, temperature, oxygen content, and conductivity. Although the streams appear pristine, multivariate statistics indicated that cadmium and zinc levels were significantly correlated with fewer animals, fewer families, a smaller percentage of plecopterans (stoneflies), and lower Shannon H diversity values. After at least 75 years, abandoned mines appear to be still influencing stream communities. PMID:20680454

  17. Rate of forest spread on abandoned farmland in Central Kansas

    SciTech Connect

    Loehle, C.; Sundell, R.; Sydelko, P. )

    1994-06-01

    A large tract of land taken out of agriculture at the Ft. Riley military base was studied for forest recovery rate using aerial photos taken 16 years apart. Controlled and uncontrolled burns occurred during this time. On dissected terrain, forest spread was substantial during this period. Forest initially occurred along stream channels. All spread was to areas immediately adjacent to existing forest. A spatially explicit contagion model modified by topography successfully predicted forest spread. In flatter terrain, no forest spread could be detected, indicating more effective regulation of forest area by fire in such locations. Implications for land management are discussed.

  18. Detecting abandoned objects using interacting multiple models

    NASA Astrophysics Data System (ADS)

    Becker, Stefan; Münch, David; Kieritz, Hilke; Hübner, Wolfgang; Arens, Michael

    2015-10-01

    In recent years, the wide use of video surveillance systems has caused an enormous increase in the amount of data that has to be stored, monitored, and processed. As a consequence, it is crucial to support human operators with automated surveillance applications. Towards this end an intelligent video analysis module for real-time alerting in case of abandoned objects in public spaces is proposed. The overall processing pipeline consists of two major parts. First, person motion is modeled using an Interacting Multiple Model (IMM) filter. The IMM filter estimates the state of a person according to a finite-state, discrete-time Markov chain. Second, the location of persons that stay at a fixed position defines a region of interest, in which a nonparametric background model with dynamic per-pixel state variables identifies abandoned objects. In case of a detected abandoned object, an alarm event is triggered. The effectiveness of the proposed system is evaluated on the PETS 2006 dataset and the i-Lids dataset, both reflecting prototypical surveillance scenarios.

  19. Biogeochemical and suspended sediment responses to permafrost degradation in stream banks in Taylor Valley, Antarctica

    NASA Astrophysics Data System (ADS)

    Gooseff, M. N.; Van Horn, D.; Sudman, Z.; McKnight, D. M.; Welch, K. A.; Lyons, W. B.

    2015-09-01

    Stream channels in the McMurdo Dry Valleys are typically wide, incised, and stable. At typical flows, streams occupy a fraction of the oversized channels, providing habitat for algal mats. In January 2012, we discovered substantial channel erosion and subsurface thermomechanical erosion undercutting banks of Crescent Stream. We sampled stream water along the impacted reach and compared concentrations of solutes to the long-term data from this stream (~20 years of monitoring). Thermokarst-impacted stream water demonstrated higher electrical conductivity, and concentrations of chloride, sulfate, sodium, suspended sediments, and nitrate than the long-term medians. These results suggest that this mode of lateral permafrost degradation may substantially impact stream solute loads and potentially fertilize stream and lake ecosystems. The potential for sediment to scour or bury stream algal mats is yet to be determined, though it may offset impacts of associated increased nutrient loads to streams.

  20. Availability and distribution of low flow in Anahola Stream, Kauaʻi, Hawaiʻi

    USGS Publications Warehouse

    Cheng, Chui Ling; Wolff, Reuben H.

    2012-01-01

    Anahola Stream is a perennial stream in northeast Kauaʻi, Hawaiʻi, that supports agricultural, domestic, and cultural uses within its drainage basin. Beginning in the late 19th century, Anahola streamflow was diverted by Makee Sugar Company at altitudes of 840 feet (upper intake) and 280 feet (lower intake) for irrigating sugarcane in the Keālia area. When sugarcane cultivation in the Keālia area ceased in 1988, part of the Makee Sugar Company’s surface-water collection system (Makee diversion system) in the Anahola drainage basin was abandoned. In an effort to better manage available surface-water resources, the State of Hawaiʻi Department of Hawaiian Home Lands is considering using the existing ditches in the Anahola Stream drainage basin to provide irrigation water for Native Hawaiian farmers in the area. To provide information needed for successful management of the surface-water resources, the U.S. Geological Survey investigated the availability and distribution of natural low flow in Anahola Stream and also collected low-flow data in Goldfish Stream, a stream that discharges into Kaneha Reservoir, which served as a major collection point for the Makee diversion system. Biological surveys of Anahola Stream were conducted as part of a study to determine the distribution of native and nonnative aquatic stream fauna. Results of the biological surveys indicated the presence of the following native aquatic species in Anahola Stream: ʻoʻopu ʻakupa (Sandwich Island sleeper) and ʻoʻopu naniha (Tear-drop goby) in the lower stream reaches surveyed; and ʻoʻopu nākea (Pacific river goby), ʻoʻopu nōpili (Stimpson’s goby), and ʻōpae kalaʻole (Mountain shrimp) in the middle and upper stream reaches surveyed. Nonnative aquatic species were found in all of the surveyed stream reaches along Anahola Stream. The availability and distribution of natural low flow were determined using a combination of discharge measurements made from February 2011 to May 2012

  1. Transverse mixing of simulated piscicides in small montane streams

    USGS Publications Warehouse

    Brown, Peter J.; Ard, Jenifer L.; Zale, Alexander V.

    2012-01-01

    Thorough mixing of piscicides into receiving waters is important for efficient and effective fish eradication. However, no guidance exists for the placement of drip stations with respect to mixing. Salt (NaCl) was used as a tracer to measure the mixing rates of center versus edge applications in riffle–pool, straight, and meandering sections of montane streams. The tracer was applied at either the center or the edge of a channel and measured with a conductivity meter across a downstream grid to determine the distances at which transverse mixing was complete. No advantage was accrued by applying piscicides in different types of channels because transverse mixing distance did not differ among them. However, mixing distance was significantly shorter at center applications. Chemicals entering a stream at the center of the channel mixed thoroughly within 10 stream widths, whereas chemicals entering a stream channel at the edge mixed thoroughly within 20 stream widths.

  2. Nitrogen Removal by Streams and Rivers of the Upper Mississippi River Basin

    EPA Science Inventory

    Our study, based on chemistry and channel dimensions data collected at 893 randomly-selected stream and river sites in the Mississippi River basin, demonstrated the interaction of stream chemistry, stream size, and NO3-N uptake metrics across a range of stream sizes and across re...

  3. Applying geomorphologic principles to restore streams impacted by surface mining

    SciTech Connect

    Ellison, M.S.

    1996-12-31

    The combination of geomorphic principles and native material restoration techniques provides a viable alternative to traditional engineering approaches to restore rivers and streams affected by surface mining. Channels can be designed to reflect ranges of stability known to occur in natural streams for measurable parameters such as bankfull width, depth, gradient, meander radius, sinuosity and entrenchment. Stable channel geometry reduces stresses on the stream bed and banks and eliminate the need for channel lining. Methods to utilize native materials have been developed and refined to stabilize stream channels constructed to appropriate dimensions until planted riparian vegetation develops mature root systems. These native materials include root wads, willow bundles, and boulders. These methods result in improved wildlife habitat in and around channels that maintain equilibria between sediment supply and sediment transport, and between erosional and depositional rates and patterns. Two streams in Baltimore County, Maryland were disturbed during mining operations and are being restored using this approach. Goodwin Run had been channelized to allow quarrying of the Cockeysville Marble. Approximately 1100 feet of stream were restored in the fall of 1992. White Marsh Run has been channelized and relocated several times to facilitate sand and gravel mining between an urbanized area and sensitive habitats of the Chesapeake Bay. The design of the White Marsh Run Restoration Project incorporated refinements to techniques used at Goodwin Run, and entails the restoration of over 5000 feet of stream and adjacent wetland habitat.

  4. Drawdown and stream depletion produced by pumping in the vicinity of a partially penetrating stream

    USGS Publications Warehouse

    Butler, J.J.; Zlotnik, V.A.; Tsou, M.-S.

    2001-01-01

    Commonly used analytical approaches for estimation of pumping-induced drawdown and stream depletion are based on a series of idealistic assumptions about the stream-aquifer system. A new solution has been developed for estimation of drawdown and stream depletion under conditions that are more representative of those in natural systems (finite width stream of shallow penetration adjoining an aquifer of limited lateral extent). This solution shows that the conventional assumption of a fully penetrating stream will lead to a significant overestimation of stream depletion (> 100 %) in many practical applications. The degree of overestimation will depend on the value of the stream leakance parameter and the distance from the pumping well to the stream. Although leakance will increase with stream width, a very wide stream will not necessarily be well represented by a model of a fully penetrating stream. The impact of lateral boundaries depends upon the distance from the pumping well to the stream and the stream leakance parameter. In most cases, aquifer width must be on the order of hundreds of stream widths before the assumption of a laterally infinite aquifer is appropriate for stream-depletion calculations. An important assumption underlying this solution is that stream-channel penetration is negligible relative to aquifer thickness. However, an approximate extension to the case of nonnegligible penetration provides reasonable results for the range of relative penetrations found in most natural systems (up to 85%). Since this solution allows consideration of a much wider range of conditions than existing analytical approaches, it could prove to be a valuable new tool for water management design and water rights adjudication purposes.

  5. Evaluation of reclaimed abandoned bentonite mine lands

    SciTech Connect

    Edinger, K.D.; Schuman, G.E.; Vance, G.F.

    1999-07-01

    In 1985, the Abandoned Mined Land Division of the Wyoming Department of Environmental Quality began reclamation of 4,148 ha of abandoned bentonite mined lands. Calcium amendments and sawmill wood wastes were applied to the regraded spoils to enhance water infiltration, displacement of Na on the clay spoil, and leaching of the displaced Na and other soluble salts. Revegetation of these lands was generally successful, but after several years small areas (0.1--0.2 ha) began to show signs of vegetation die-back and to prescribe corrective treatment options. A randomized block design was imposed on study areas near Upton, Colony, and Greybull, Wyoming to characterize spoil chemical properties of good, moderate, and dead vegetation zones, which were subjectively delineated by visual vegetation cover and density differences. Spoil analyses indicated exchangeable-sodium (Na) concentrations were high and the dead vegetation zones exhibited exchangeable-sodium-percentages (ESP) above 50%, while surrounding good vegetation zones exhibited ESP values <10%. This coupled with low soluble-Na concentrations (<2 cmol/kg) suggests insufficient calcium (Ca) amendments were initially applied to ameliorate the sodic conditions of the spoil. The sampling design used to determine Ca amendment rates, which consisted of a composite of 5 spoil cores taken from each 0.8 ha area, was apparently insufficient to account for the highly heterogeneous spoil material that occurred throughout these abandoned bentonite reclamation sites. To revegetate these small degraded sites, additional Ca amendment would be necessary and reseeding would be required. However, the authors recommend further monitoring of the affected sites to determine if unfavorable conditions continue to degrade the reclaimed landscape before any attempt is made to rehabilitate the affected sites. If the degraded sites are stable, further Remediation efforts are not warranted because small areas of little or no vegetation are

  6. Stream-subsurface nutrient dynamics in a groundwater-fed stream

    NASA Astrophysics Data System (ADS)

    Rezanezhad, F.; Niederkorn, A.; Parsons, C. T.; Van Cappellen, P.

    2015-12-01

    The stream-riparian-aquifer interface plays a major role in the regional flow of nutrients and contaminants due to a strong physical-chemical gradient that promotes the transformation, retention, elimination or release of biogenic elements. To better understand the effect of the near-stream zones on stream biogeochemistry, we conducted a field study on a groundwater-fed stream located in the rare Charitable Research Reserve, Cambridge, Ontario, Canada. This study focused on monitoring the spatial and temporal distributions of nutrient elements within the riparian and hyporheic zones of the stream. Several piezometer nests and a series of passive (diffusion) water samplers, known as peepers, were installed along longitudinal and lateral transects centered on the stream to obtain data on the groundwater chemistry. Groundwater upwelling along the stream resulted in distinctly different groundwater types and associated nitrate concentrations between small distances in the riparian zone (<4m). After the upstream source of the stream surface water, concentrations of nutrients (NO3-, NH4+, SO42- and carbon) did not significantly change before the downstream outlet. Although reduction of nitrate and sulphate were found in the riparian zone of the stream, this did not significantly influence the chemistry of the adjacent stream water. Also, minimal retention in the hyporheic zones limited reduction of reactive compounds (NO3- and SO42-) within the stream channel. The results showed that the dissolved organic carbon (DOC) and residence time of water in the hyporheic zone and in surface water limited denitrification.

  7. Availability and distribution of low flow in Anahola Stream, Kauaʻi, Hawaiʻi

    USGS Publications Warehouse

    Cheng, Chui Ling; Wolff, Reuben H.

    2012-01-01

    Anahola Stream is a perennial stream in northeast Kauaʻi, Hawaiʻi, that supports agricultural, domestic, and cultural uses within its drainage basin. Beginning in the late 19th century, Anahola streamflow was diverted by Makee Sugar Company at altitudes of 840 feet (upper intake) and 280 feet (lower intake) for irrigating sugarcane in the Keālia area. When sugarcane cultivation in the Keālia area ceased in 1988, part of the Makee Sugar Company’s surface-water collection system (Makee diversion system) in the Anahola drainage basin was abandoned. In an effort to better manage available surface-water resources, the State of Hawaiʻi Department of Hawaiian Home Lands is considering using the existing ditches in the Anahola Stream drainage basin to provide irrigation water for Native Hawaiian farmers in the area. To provide information needed for successful management of the surface-water resources, the U.S. Geological Survey investigated the availability and distribution of natural low flow in Anahola Stream and also collected low-flow data in Goldfish Stream, a stream that discharges into Kaneha Reservoir, which served as a major collection point for the Makee diversion system. Biological surveys of Anahola Stream were conducted as part of a study to determine the distribution of native and nonnative aquatic stream fauna. Results of the biological surveys indicated the presence of the following native aquatic species in Anahola Stream: ʻoʻopu ʻakupa (Sandwich Island sleeper) and ʻoʻopu naniha (Tear-drop goby) in the lower stream reaches surveyed; and ʻoʻopu nākea (Pacific river goby), ʻoʻopu nōpili (Stimpson’s goby), and ʻōpae kalaʻole (Mountain shrimp) in the middle and upper stream reaches surveyed. Nonnative aquatic species were found in all of the surveyed stream reaches along Anahola Stream. The availability and distribution of natural low flow were determined using a combination of discharge measurements made from February 2011 to May 2012

  8. Channel metamorphosis, floodplain disturbance, and vegetation development: Ain River, France

    NASA Astrophysics Data System (ADS)

    Marston, Richard A.; Girel, Jacky; Pautou, Guy; Piegay, Herve; Bravard, Jean-Paul; Arneson, Chris

    1995-09-01

    The purpose of this paper is to describe and explain channel metamorphosis of the Ain River in east-central France and the effects of this metamorphosis on floodplain disturbance and vegetation development. The Ain River is a 195 km long stream originating in the Jura Mountains which flows into the Rhône River between Lyon, France, and Geneva, Switzerland. The lower 40 km of the Ain River, beyond the mountain front, are situated in a valley of outwash deposits where the floodplain is 0.2 to 1.2 km wide. A complex mosaic of floodplain landscape units has developed. Maps dating back to 1766 and six sets of aerial photographs dated between 1945 and 1991 were used to document changes in channel pattern. Aerial photos and field surveys were used to compile maps of landscape units based on dominant vegetation life-forms, species, and substrate. Six maps dated between 1945 and 1991 were digitized in ARC/INFO and an overlay was generated to determine the changes in landscape units as related to channel disturbance. Change from a braided to a single-thread meandering channel probably took place in the period 1930-1950. The process of river entrenchment has occurred throughout the Holocene but has accelerated in the present century due to shortening of the river course, construction of lateral embankments, and vegetation encroachment following reservoir construction and cessation of wood-cutting and grazing. The increase in horizontal channel stability coupled with channel entrenchment have decreased floodplain disturbance and lowered the water table by approximately one meter. Pioneer and disturbance-dependent landscape units have experienced a more terrestrial-like succession to an alluvial forest. Abandoned channels have also been replaced by alluvial forests. On poorly drained soils, shrub-swamp communities of willow and hydrophytic herbaceous plants have been replaced by mixed forests of ash, alder, black poplar, and oak. On well drained alluvial soils, ash and oak

  9. Hydrogeochemical niches associated with hyporheic exchange beneath an acid mine drainage-contaminated stream

    NASA Astrophysics Data System (ADS)

    Larson, Lance N.; Fitzgerald, Michael; Singha, Kamini; Gooseff, Michael N.; Macalady, Jennifer L.; Burgos, William

    2013-09-01

    Biological low-pH Fe(II)-oxidation creates terraced iron formations (TIFs) that remove Fe(III) from solution. TIFs can be used for remediation of acid mine drainage (AMD), however, as sediment depth increases, Fe(III)-reduction in anoxic subsurface areas may compromise treatment effectiveness. In this study we used near-surface electrical resistivity imaging (ERI) and in situ pore-water samplers to spatially resolve bulk conductivity changes within a TIF formed in a stream emanating from a large abandoned deep clay mine in Cambria County, Pennsylvania, USA. Because of the high fluid electrical conductivity of the emergent AMD (1860 μS), fresh water (42 μS) was added as a dilution tracer to visualize the spatial and temporal extent of hyporheic exchange and to characterize subsurface flow paths. Distinct hydrogeochemical niches were identified in the shallow subsurface beneath the stream by overlaying relative groundwater velocities (derived from ERI) with pore-water chemistry profiles. Niches were classified based on relatively “fast” versus “slow” rates of hyporheic exchange and oxic versus anoxic conditions. Pore-water concentrations and speciation of iron, pH, and redox potential differed between subsurface flow regimes. The greatest extent of hyporheic exchange was beneath the center of the stream, where a shallower (<10 cm) Fe(II)-oxidizing zone was observed. Meanwhile, less hyporheic exchange was observed near the channel banks, concurrent with a more pronounced, deeper (>70 cm) Fe(II)-oxidizing zone. At these locations, relatively slower groundwater exchange may promote biotic Fe(II)-oxidation and improve the long-term stability of Fe sequestered in TIFs.

  10. Limitations and implications of stream classification

    USGS Publications Warehouse

    Juracek, K.E.; Fitzpatrick, F.A.

    2003-01-01

    Stream classifications that are based on channel form, such as the Rosgen Level II classification, are useful tools for the physical description and grouping of streams and for providing a means of communication for stream studies involving scientists and (or) managers with different backgrounds. The Level II classification also is used as a tool to assess stream stability, infer geomorphic processes, predict future geomorphic response, and guide stream restoration or rehabilitation activities. The use of the Level II classification for these additional purposes is evaluated in this paper. Several examples are described to illustrate the limitations and management implications of the Level II classification. Limitations include: (1) time dependence, (2) uncertain applicability across physical environments, (3) difficulty in identification of a true equilibrium condition, (4) potential for incorrect determination of bankfull elevation, and (5) uncertain process significance of classification criteria. Implications of using stream classifications based on channel form, such as Rosgen's, include: (1) acceptance of the limitations, (2) acceptance of the risk of classifying streams incorrectly, and (3) classification results may be used inappropriately. It is concluded that use of the Level II classification for purposes beyond description and communication is not appropriate. Research needs are identified that, if addressed, may help improve the usefulness of the Level II classification.

  11. Roughness characteristics of natural channels

    USGS Publications Warehouse

    Barnes, Harry Hawthorne

    1967-01-01

    Color photographs and descriptive data are presented for 50 stream channels for which roughness coefficients have been determined. All hydraulic computations involving flow in open channels require an evaluation of the roughness characteristics of the channel. In the absence of a satisfactory quantitative procedure this evaluation remains chiefly an art. The ability to evaluate roughness coefficients must be developed through experience. One means of gaining this experience is by examining and becoming acquainted with the appearance of some typical channels whose roughness coefficients are known. The photographs and data contained in this report represent a wide range of channel conditions. Familiarity with the appearance, geometry, and roughness characteristics of these channels will improve the engineer's ability to select roughness coefficients for other channels .

  12. 77 FR 43656 - BNSF Railway Company-Abandonment Exemption-in Los Angeles County, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-25

    ... Surface Transportation Board BNSF Railway Company--Abandonment Exemption--in Los Angeles County, CA BNSF... Abandonments to abandon its freight rail operating easement over a 5.3-mile line of railroad owned by the Los... abandonment shall be protected under Oregon Short Line Railroad-- ] Abandonment Portion Goshen Branch...

  13. 75 FR 40862 - Grand Trunk Western Railroad Company-Abandonment Exemption-in Macomb County, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-14

    ... Surface Transportation Board Grand Trunk Western Railroad Company--Abandonment Exemption--in Macomb County.... 1152 Subpart F-Exempt Abandonments to abandon its line of railroad between milepost 0.00 and milepost 0... affected by the abandonment shall be protected under Oregon Short Line Railroad--Abandonment Portion...

  14. 77 FR 26602 - BNSF Railway Company-Abandonment Exemption-in Walsh and Pembina Counties, ND

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-04

    ... Surface Transportation Board BNSF Railway Company--Abandonment Exemption--in Walsh and Pembina Counties... subpart F-Exempt Abandonments to abandon 18.12 miles of rail line located between milepost 42.08 at... abandonment shall be protected under Oregon Short Line Railroad--Abandonment Portion Goshen Branch...

  15. 43 CFR 3263.10 - May I abandon a well without BLM's approval?

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... LEASING Well Abandonment § 3263.10 May I abandon a well without BLM's approval? (a) You must have a BLM-approved Sundry Notice documenting your plugging and abandonment program before you start abandoning any well. (b) You must also notify the local BLM office before you begin abandonment activities, so that...

  16. 76 FR 31008 - CSX Transportation, Inc.-Abandonment Exemption-in Erie County, NY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-27

    ... Surface Transportation Board CSX Transportation, Inc.--Abandonment Exemption--in Erie County, NY CSX... Abandonments to abandon an approximately 0.56-mile rail line on its Northern Region, Albany Division, Buffalo... abandonment shall be protected under Oregon Short Line Railroad--Abandonment Portion Goshen Branch...

  17. 76 FR 72241 - BNSF Railway Company-Abandonment Exemption-in Cass County, ND

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-22

    ... Surface Transportation Board BNSF Railway Company--Abandonment Exemption--in Cass County, ND BNSF Railway... Abandonments to abandon 7.40 miles of rail line extending between milepost 68.10 at Arthur and milepost 75.50... ] abandonment shall be protected under Oregon Short Line Railroad-- Abandonment Portion Goshen Branch...

  18. 76 FR 43374 - CSX Transportation, Inc.; Abandonment Exemption; in Hardin County, OH

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-20

    ... Surface Transportation Board CSX Transportation, Inc.; Abandonment Exemption; in Hardin County, OH CSX... Abandonments to abandon an approximately 0.21-mile rail line on its Northern Region, Toledo Branch Subdivision... abandonment shall be protected under Oregon Short Line Railroad--Abandonment Portion Goshen Branch...

  19. 76 FR 51470 - CSX Transportation, Inc.-Abandonment Exemption-In Oswego County, NY

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-18

    ... Surface Transportation Board CSX Transportation, Inc.--Abandonment Exemption--In Oswego County, NY CSX... Abandonments to abandon 2 formerly connected rail lines in CSXT's Northern Region, Albany Division, Fulton... affected by the abandonment shall be protected under Oregon Short Line Railroad--Abandonment Portion...

  20. 78 FR 21494 - Union Pacific Railroad Company-Abandonment Exemption-in Washington County, Idaho

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-10

    ... Surface Transportation Board Union Pacific Railroad Company--Abandonment Exemption--in Washington County.... 1152 subpart F--Exempt Abandonments to abandon 0.28 miles of rail line (New Meadows Industrial Lead... abandonment shall be protected under Oregon Short Line Railroad--Abandonment Portion Goshen Branch...

  1. Re-meandering of lowland streams: will disobeying the laws of geomorphology have ecological consequences?

    PubMed

    Pedersen, Morten Lauge; Kristensen, Klaus Kevin; Friberg, Nikolai

    2014-01-01

    We evaluated the restoration of physical habitats and its influence on macroinvertebrate community structure in 18 Danish lowland streams comprising six restored streams, six streams with little physical alteration and six channelized streams. We hypothesized that physical habitats and macroinvertebrate communities of restored streams would resemble those of natural streams, while those of the channelized streams would differ from both restored and near-natural streams. Physical habitats were surveyed for substrate composition, depth, width and current velocity. Macroinvertebrates were sampled along 100 m reaches in each stream, in edge habitats and in riffle/run habitats located in the center of the stream. Restoration significantly altered the physical conditions and affected the interactions between stream habitat heterogeneity and macroinvertebrate diversity. The substrate in the restored streams was dominated by pebble, whereas the substrate in the channelized and natural streams was dominated by sand. In the natural streams a relationship was identified between slope and pebble/gravel coverage, indicating a coupling of energy and substrate characteristics. Such a relationship did not occur in the channelized or in the restored streams where placement of large amounts of pebble/gravel distorted the natural relationship. The analyses revealed, a direct link between substrate heterogeneity and macroinvertebrate diversity in the natural streams. A similar relationship was not found in either the channelized or the restored streams, which we attribute to a de-coupling of the natural relationship between benthic community diversity and physical habitat diversity. Our study results suggest that restoration schemes should aim at restoring the natural physical structural complexity in the streams and at the same time enhance the possibility of re-generating the natural geomorphological processes sustaining the habitats in streams and rivers. Documentation of

  2. Re-meandering of lowland streams: will disobeying the laws of geomorphology have ecological consequences?

    PubMed

    Pedersen, Morten Lauge; Kristensen, Klaus Kevin; Friberg, Nikolai

    2014-01-01

    We evaluated the restoration of physical habitats and its influence on macroinvertebrate community structure in 18 Danish lowland streams comprising six restored streams, six streams with little physical alteration and six channelized streams. We hypothesized that physical habitats and macroinvertebrate communities of restored streams would resemble those of natural streams, while those of the channelized streams would differ from both restored and near-natural streams. Physical habitats were surveyed for substrate composition, depth, width and current velocity. Macroinvertebrates were sampled along 100 m reaches in each stream, in edge habitats and in riffle/run habitats located in the center of the stream. Restoration significantly altered the physical conditions and affected the interactions between stream habitat heterogeneity and macroinvertebrate diversity. The substrate in the restored streams was dominated by pebble, whereas the substrate in the channelized and natural streams was dominated by sand. In the natural streams a relationship was identified between slope and pebble/gravel coverage, indicating a coupling of energy and substrate characteristics. Such a relationship did not occur in the channelized or in the restored streams where placement of large amounts of pebble/gravel distorted the natural relationship. The analyses revealed, a direct link between substrate heterogeneity and macroinvertebrate diversity in the natural streams. A similar relationship was not found in either the channelized or the restored streams, which we attribute to a de-coupling of the natural relationship between benthic community diversity and physical habitat diversity. Our study results suggest that restoration schemes should aim at restoring the natural physical structural complexity in the streams and at the same time enhance the possibility of re-generating the natural geomorphological processes sustaining the habitats in streams and rivers. Documentation of

  3. Re-Meandering of Lowland Streams: Will Disobeying the Laws of Geomorphology Have Ecological Consequences?

    PubMed Central

    Pedersen, Morten Lauge; Kristensen, Klaus Kevin; Friberg, Nikolai

    2014-01-01

    We evaluated the restoration of physical habitats and its influence on macroinvertebrate community structure in 18 Danish lowland streams comprising six restored streams, six streams with little physical alteration and six channelized streams. We hypothesized that physical habitats and macroinvertebrate communities of restored streams would resemble those of natural streams, while those of the channelized streams would differ from both restored and near-natural streams. Physical habitats were surveyed for substrate composition, depth, width and current velocity. Macroinvertebrates were sampled along 100 m reaches in each stream, in edge habitats and in riffle/run habitats located in the center of the stream. Restoration significantly altered the physical conditions and affected the interactions between stream habitat heterogeneity and macroinvertebrate diversity. The substrate in the restored streams was dominated by pebble, whereas the substrate in the channelized and natural streams was dominated by sand. In the natural streams a relationship was identified between slope and pebble/gravel coverage, indicating a coupling of energy and substrate characteristics. Such a relationship did not occur in the channelized or in the restored streams where placement of large amounts of pebble/gravel distorted the natural relationship. The analyses revealed, a direct link between substrate heterogeneity and macroinvertebrate diversity in the natural streams. A similar relationship was not found in either the channelized or the restored streams, which we attribute to a de-coupling of the natural relationship between benthic community diversity and physical habitat diversity. Our study results suggest that restoration schemes should aim at restoring the natural physical structural complexity in the streams and at the same time enhance the possibility of re-generating the natural geomorphological processes sustaining the habitats in streams and rivers. Documentation of

  4. Beaded streams of Arctic permafrost landscapes

    NASA Astrophysics Data System (ADS)

    Arp, C. D.; Whitman, M. S.; Jones, B. M.; Grosse, G.; Gaglioti, B. V.; Heim, K. C.

    2014-07-01

    Beaded streams are widespread in permafrost regions and are considered a common thermokarst landform. However, little is known about their distribution, how and under what conditions they form, and how their intriguing morphology translates to ecosystem functions and habitat. Here we report on a Circum-Arctic inventory of beaded streams and a watershed-scale analysis in northern Alaska using remote sensing and field studies. We mapped over 400 channel networks with beaded morphology throughout the continuous permafrost zone of northern Alaska, Canada, and Russia and found the highest abundance associated with medium- to high-ice content permafrost in moderately sloping terrain. In the Fish Creek watershed, beaded streams accounted for half of the drainage density, occurring primarily as low-order channels initiating from lakes and drained lake basins. Beaded streams predictably transition to alluvial channels with increasing drainage area and decreasing channel slope, although this transition is modified by local controls on water and sediment delivery. Comparison of one beaded channel using repeat photography between 1948 and 2013 indicate relatively stable form and 14C dating of basal sediments suggest channel formation may be as early as the Pleistocene-Holocene transition. Contemporary processes, such as deep snow accumulation in stream gulches effectively insulates river ice and allows for perennial liquid water below most beaded stream pools. Because of this, mean annual temperatures in pool beds are greater than 2 °C, leading to the development of perennial thaw bulbs or taliks underlying these thermokarst features. In the summer, some pools stratify thermally, which reduces permafrost thaw and maintains coldwater habitats. Snowmelt generated peak-flows decrease rapidly by two or more orders of magnitude to summer low flows with slow reach-scale velocity distributions ranging from 0.1 to 0.01 m s-1, yet channel runs still move water rapidly between pools

  5. Biology in focus: better lives through better science: new hope for acid streams

    USGS Publications Warehouse

    Watten, Barnaby

    1998-01-01

    Across the nation, a toxic pollutant turns clean streams orange, kills fish and plant life, and smells like rotten eggs. The culprit is acid mine drainage, the poisonous water leaking from more than 500,000 abandoned and inactive mines in 32 states. The toxic discharge is a problem for operational mines as well. In the Appalachian coal region, for example, acid mine drainage has degraded more than 8,000 miles of streams and has left some aquatic habitats virtually lifeless.

  6. ENHANCING HSPF MODEL CHANNEL HYDRAULIC REPRESENTATION

    EPA Science Inventory

    The Hydrological Simulation Program - FORTRAN (HSPF) is a comprehensive watershed model, which employs depth-area-volume-flow relationships known as hydraulic function table (FTABLE) to represent stream channel cross-sections and reservoirs. An accurate FTABLE determination for a...

  7. 42 CFR 498.69 - Dismissal for abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 5 2014-10-01 2014-10-01 false Dismissal for abandonment. 498.69 Section 498.69 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... IN THE MEDICAID PROGRAM Hearings § 498.69 Dismissal for abandonment. (a) The ALJ may dismiss...

  8. 42 CFR 422.1060 - Dismissal for abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Dismissal for abandonment. 422.1060 Section 422.1060 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Penalties § 422.1060 Dismissal for abandonment. (a) The ALJ may dismiss a request for hearing if it...

  9. 43 CFR 3595.2 - Abandonment of underground workings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Abandonment of underground workings. 3595.2 Section 3595.2 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF...) EXPLORATION AND MINING OPERATIONS Protection Against Mining Hazards § 3595.2 Abandonment of...

  10. 40 CFR 147.3104 - Notice of abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Notice of abandonment. 147.3104 Section 147.3104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Oklahoma Indian Tribes § 147.3104 Notice of abandonment. (a) In addition to the notice required by §...

  11. 40 CFR 147.2905 - Plugging and abandonment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 24 2013-07-01 2013-07-01 false Plugging and abandonment. 147.2905 Section 147.2905 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS...-Class II Wells § 147.2905 Plugging and abandonment. The owner/operator shall notify the Osage UIC...

  12. 42 CFR 498.69 - Dismissal for abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 5 2012-10-01 2012-10-01 false Dismissal for abandonment. 498.69 Section 498.69 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... IN THE MEDICAID PROGRAM Hearings § 498.69 Dismissal for abandonment. (a) The ALJ may dismiss...

  13. 40 CFR 147.3104 - Notice of abandonment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 23 2011-07-01 2011-07-01 false Notice of abandonment. 147.3104 Section 147.3104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Oklahoma Indian Tribes § 147.3104 Notice of abandonment. (a) In addition to the notice required by §...

  14. 19 CFR 147.46 - Voluntary abandonment or destruction.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 19 Customs Duties 2 2010-04-01 2010-04-01 false Voluntary abandonment or destruction. 147.46 Section 147.46 Customs Duties U.S. CUSTOMS AND BORDER PROTECTION, DEPARTMENT OF HOMELAND SECURITY... Voluntary abandonment or destruction. At any time before or within 3 months after the closing date of...

  15. 42 CFR 423.1060 - Dismissal for abandonment.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Dismissal for abandonment. 423.1060 Section 423.1060 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Civil Money Penalties § 423.1060 Dismissal for abandonment. (a) The ALJ may dismiss a request...

  16. 40 CFR 147.3105 - Plugging and abandonment report.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Plugging and abandonment report. 147.3105 Section 147.3105 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER... Certain Oklahoma Indian Tribes § 147.3105 Plugging and abandonment report. (a) In lieu of the time...

  17. Book review: old fields: dynamics and restoration of abandoned farmland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The 2007 volume, “Old Fields: Dynamics and Restoration of Abandoned Farmland”, edited by VA Cramer and RJ Hobbs and published by the Society for Ecological Restoration International (Island Press), is a valuable attempt to synthesize a dozen case studies on agricultural abandonment from all of the ...

  18. 40 CFR 147.3104 - Notice of abandonment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Notice of abandonment. 147.3104 Section 147.3104 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS... Oklahoma Indian Tribes § 147.3104 Notice of abandonment. (a) In addition to the notice required by §...

  19. 5 CFR 1650.15 - Abandonment of inactive accounts.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 3 2011-01-01 2011-01-01 false Abandonment of inactive accounts. 1650.15 Section 1650.15 Administrative Personnel FEDERAL RETIREMENT THRIFT INVESTMENT BOARD METHODS OF WITHDRAWING FUNDS FROM THE THRIFT SAVINGS PLAN Post-Employment Withdrawals § 1650.15 Abandonment of...

  20. 40 CFR 147.2905 - Plugging and abandonment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 23 2014-07-01 2014-07-01 false Plugging and abandonment. 147.2905 Section 147.2905 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) WATER PROGRAMS...-Class II Wells § 147.2905 Plugging and abandonment. The owner/operator shall notify the Osage UIC...