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Sample records for brahmaputra river

  1. Antecedence of the Yarlung-Siang-Brahmaputra River, eastern Himalaya

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    Lang, Karl A.; Huntington, Katharine W.

    2014-07-01

    At the eastern terminus of the Himalayan orogen, distortion and capture of southeast Asian drainage basins reflects regional patterns of crustal strain due to the indentation of the Indian Plate into Eurasia. After flowing eastward >1000 km along the southern margin of Tibet, the Yarlung-Siang-Brahmaputra River turns abruptly southward through the eastern Himalayan syntaxis rapidly exhuming a crustal scale antiform in an impressive >2 km knickpoint. This conspicuous drainage pattern and coincidence of focused fluvial incision and rapid rock exhumation has been explained by the capture of an ancestral, high-elevation Yarlung River by headward erosion of a Himalayan tributary. However, recent observation of Tibetan detritus in Neogene foreland basin units complicates this explanation, requiring a connection from Tibet to the foreland prior to the estimated onset of rapid rock exhumation. We constrain the sedimentary provenance of foreland basin units deposited near the Brahmaputra River confluence in the eastern Himalayan foreland basin using detrital zircon U-Pb geochronology. We interpret the significant presence of Gangdese-age detritus in each foreland basin unit to indicate that connection of the Yarlung-Siang-Brahmaputra River was established during, or prior to foreland deposition in the Early Miocene. Our results indicate that connection of the Yarlung-Siang-Brahmaputra River precedes exhumation of the syntaxis, demonstrating the potential for the progressive coevolution of rock uplift and rapid erosion of the Namche Barwa massif.

  2. Using radar altimetry to update a large-scale hydrological model of the Brahmaputra river basin

    DEFF Research Database (Denmark)

    Finsen, F.; Milzow, Christian; Smith, R.

    2014-01-01

    of the Brahmaputra is excellent (17 high-quality virtual stations from ERS-2, 6 from Topex and 10 from Envisat are available for the Brahmaputra). In this study, altimetry data are used to update a large-scale Budyko-type hydrological model of the Brahmaputra river basin in real time. Altimetry measurements...... are converted to discharge using rating curves of simulated discharge versus observed altimetry. This approach makes it possible to use altimetry data from river cross sections where both in-situ rating curves and accurate river cross section geometry are not available. Model updating based on radar altimetry...

  3. CryoSat-2 altimetry for river level monitoring - Evaluation in the Ganges-Brahmaputra River basin

    DEFF Research Database (Denmark)

    Villadsen, Heidi; Andersen, Ole B.; Stenseng, Lars

    2015-01-01

    larger differences. For five virtual stations in the Brahmaputra River, the mean difference between the obtained amplitudes is similar to 10 cm, whereas the mean phase difference is less than 2.7 days. A virtual station in the Ganges River shows a phase difference of around 5 days and a difference...

  4. The Brahmaputra tale of tectonics and erosion: Early Miocene river capture in the Eastern Himalaya

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    Bracciali, Laura; Najman, Yani; Parrish, Randall R.; Akhter, Syed H.; Millar, Ian

    2015-04-01

    The Himalayan orogen provides a type example on which a number of models of the causes and consequences of crustal deformation are based and it has been suggested that it is the site of a variety of feedbacks between tectonics and erosion. Within the broader orogen, fluvial drainages partly reflect surface uplift, different climatic zones and a response to crustal deformation. In the eastern Himalaya, the unusual drainage configuration of the Yarlung Tsangpo-Brahmaputra River has been interpreted either as antecedent drainage distorted by the India-Asia collision (and as such applied as a passive strain marker of lateral extrusion), latest Neogene tectonically-induced river capture, or glacial damming-induced river diversion events. Here we apply a multi-technique approach to the Neogene paleo-Brahmaputra deposits of the Surma Basin (Bengal Basin, Bangladesh) to test the long-debated occurrence and timing of river capture of the Yarlung Tsangpo by the Brahmaputra River. We provide U-Pb detrital zircon and rutile, isotopic (Sr-Nd and Hf) and petrographic evidence consistent with river capture of the Yarlung Tsangpo by the Brahmaputra River in the Early Miocene. We document influx of Cretaceous-Paleogene zircons in Early Miocene sediments of the paleo-Brahmaputra River that we interpret as first influx of material from the Asian plate (Transhimalayan arc) indicative of Yarlung Tsangpo contribution. Prior to capture, the predominantly Precambrian-Paleozoic zircons indicate that only the Indian plate was drained. Contemporaneous with Transhimalayan influx reflecting the river capture, we record arrival of detrital material affected by Cenozoic metamorphism, as indicated by rutiles and zircons with Cenozoic U-Pb ages and an increase in metamorphic grade of detritus as recorded by petrography. We interpret this as due to a progressively increasing contribution from the erosion of the metamorphosed core of the orogen. Whole rock Sr-Nd isotopic data from the same samples

  5. Annual cycle in lakes and rivers from CryoSat-2 altimetry — The Brahmaputra river

    DEFF Research Database (Denmark)

    Villadsen, Heidi; Andersen, Ole Baltazar; Stenseng, Lars

    2014-01-01

    A key concern of the CryoSat-2 orbit has been its long repeat period of 369 days, which is usually undesirable for river and lake monitoring. However, the results of this study show that CryoSat-2 data can indeed be used for such monitoring by utilizing the high spatial coverage and the sub......-cycle period of 30 days. The performance of CryoSat-2/SIRAL altimetry for river level monitoring is investigated by studying river levels retrieved from Ganges and Brahmaputra. An evaluation of CryoSat-2 river levels from LRM, SAR and SARIn data is performed by comparing with Envisat data from the period...... in which the two missions overlapped (2010–2012). Time series constructed using simple linear interpolation are fitted with a model to compare the captured annual signals and amplitudes. The annual cycles seen in CryoSat-2 and Envisat altimetry data agree very well and provide confidence in using CryoSat-2...

  6. Flood Frequency Analysis for Jiya Dhol River of Brahmaputra Valley

    OpenAIRE

    Luna Moni Das; Zahid Husain Qureshi

    2014-01-01

    Flood frequency analysis is an important mathematical modelling technique in determining the return period of the probability of witnessing a particular discharge in a river, especially a peak discharge. Floods as periodic events in a river basin are associated with high discharge. In flood frequency analysis the annual peak discharge in a river is fitted in different probability distributions. Three important statistical methods, most commonly used in flood frequency analysis, are - Gumbel’s...

  7. Predictability of current and future multi-river discharges: Ganges, Brahmaputra, Yangtze, Blue Nile, and Murray-Darling rivers

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    Jian, Jun

    2007-12-01

    Determining river discharge is of critical importance to many societies as they struggle with fresh water supply and risk of flooding. In Bangladesh, floods occur almost every year but with sufficient irregularity to have adverse social and economical consequences. Important goals are to predict the discharge to be used for the optimization of agricultural practices, disaster mitigation and water resource management. The aim of this study is to determine the predictability of river discharge in a number of major rivers on time scale varying from weeks to a century. We investigated predictability considering relationship between SST and discharge. Next, we consider IPCC model projections of river discharge while the models are statistically adjusted against observed discharges. In this study, we consider five rivers, the Ganges, the Brahmaputra, the Yangtze, the Blue Nile, and the Murray-Darling Rivers. On seasonal time scales, statistically significant correlations are found between mean monthly equatorial Pacific sea surface temperature (SST) and the summer Ganges discharge with lead times of 2-3 months due to oscillations of the El Nino-Southern Oscillation (ENSO) phenomena. In addition, there are strong correlations in the southwest and northeast Pacific. These, too, appear to be tied to the ENSO cycle. The Brahmaputra discharge, on the other hand, shows somewhat weaker relationships with tropical SST. Strong lagged correlations relationships are found with SST in the Bay of Bengal but these are the result of very warm SSTs and exceptional Brahmaputra discharge during the summer of 1998. When this year is removed from the time series, relationships weaken everywhere except in the northwestern Pacific for the June discharge and in areas of the central Pacific straddling the equator for the July discharge. The relationships are relative strong, but they are persistent from month to month and suggest that two different and sequential factors influence Brahmaputra

  8. Interesting rotifers (Rotifera: Eurotatoria from floodplain lakes of lower Brahmaputra river basin of Assam, northeast India

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    Sharma, B.K.

    2016-06-01

    Full Text Available The plankton and semi-plankton samples collected from four floodplain lakes (beels of Barpeta district of lower Brahmaputra river basin, Assam state, northeastern India (NEI revealed eighteen rotifer species of biodiversity and biogeographic interest belonging to five families and six genera. One species is new to the Indian Rotifera and one species is new to Assam. Our collections are characterized by two Australasian elements, five Oriental endemics, seven paleotropical species, and one cosmo (sub tropical species. Nine species, restricted to date to NEI, are examples of regional distribution importance in India while six species depicted disjunct distribution in the country. Interestingly, seven species are categorized as Eastern hemisphere elements. All the taxa are illustrated to warrant validation as an increasing magnitude of ‘unverifiable records’ is a serious impediment for the progress of rotifer biodiversity in India.

  9. Downstream and seasonal changes of lithium isotope ratios in the Ganges-Brahmaputra river system

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    Manaka, Takuya; Araoka, Daisuke; Yoshimura, Toshihiro; Hossain, H. M. Zakir; Nishio, Yoshiro; Suzuki, Atsushi; Kawahata, Hodaka

    2017-08-01

    The Li isotope ratio (δ7Li) is expected to be a useful tracer of silicate weathering in river and groundwater systems, which is an important contributor to the seawater compositional changes that accompany the evolution of the Earth's surface environment. To obtain accurate estimates of continental Li fluxes to the ocean, we determined δ7Li values of dissolved Li in the lower Ganges-Brahmaputra river system in both the dry and rainy seasons, and in deep groundwater in the Bengal basin. Dissolved Li and δ7Li values in the lower reaches of the rivers (0.04-0.66 µmol kg-1 and +19.1‰ to +34.2‰, respectively) were predominantly derived from silicate weathering, as is the case in the upper parts of these rivers. We observed large changes in δ7Li over a distance of more than 1000 km downstream that were due mainly to Rayleigh-type removal of Li from river water. Extremely high Li concentrations (1.15-1.67 µmol kg-1) and low δ7Li values (+5.1‰ to +11.6‰) in groundwater samples indicate congruent isotope leaching and dissolution of silicate minerals in the deep aquifer, where the water residence time is long. In the rainy season, Li concentrations and δ7Li values were lower than in the dry season, owing to the shorter residence time of river water and the substantial input of local subsurface flow through lowland alluvium. These results suggest that accurate estimation of continental Li fluxes to the ocean should take account of downstream and seasonal changes, as well as aquifer depth variations, in δ7Li values.

  10. Assessing regional climate simulations of the last 30 years (1982-2012) over Ganges-Brahmaputra-Meghna River Basin

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    Khandu; Awange, Joseph L.; Anyah, Richard; Kuhn, Michael; Fukuda, Yoichi

    2017-10-01

    The Ganges-Brahmaputra-Meghna (GBM) River Basin presents a spatially diverse hydrological regime due to it's complex topography and escalating demand for freshwater resources. This presents a big challenge in applying the current state-of-the-art regional climate models (RCMs) for climate change impact studies in the GBM River Basin. In this study, several RCM simulations generated by RegCM4.4 and PRECIS are assessed for their seasonal and interannual variations, onset/withdrawal of the Indian monsoon, and long-term trends in precipitation and temperature from 1982 to 2012. The results indicate that in general, RegCM4.4 and PRECIS simulations appear to reasonably reproduce the mean seasonal distribution of precipitation and temperature across the GBM River Basin, although the two RCMs are integrated over a different domain size. On average, the RegCM4.4 simulations overestimate monsoon precipitation by {˜ }26 and {˜ }5% in the Ganges and Brahmaputra-Meghna River Basin, respectively, while PRECIS simulations underestimate (overestimate) the same by {˜ }7% ({˜ }16%). Both RegCM4.4 and PRECIS simulations indicate an intense cold bias (up to 10° C) in the Himalayas, and are generally stronger in the RegCM4.4 simulations. Additionally, they tend to produce high precipitation between April and May in the Ganges (RegCM4.4 simulations) and Brahmaputra-Meghna (PRECIS simulations) River Basins, resulting in early onset of the Indian monsoon in the Ganges River Basin. PRECIS simulations exhibit a delayed monsoon withdrawal in the Brahmaputra-Meghna River Basin. Despite large spatial variations in onset and withdrawal periods across the GBM River Basin, the basin-averaged results agree reasonably well with the observed periods. Although global climate model (GCM) driven simulations are generally poor in representing the interannual variability of precipitation and winter temperature variations, they tend to agree well with observed precipitation anomalies when driven by

  11. Groundwater arsenic contamination in Brahmaputra river basin: a water quality assessment in Golaghat (Assam), India.

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    Chetia, Mridul; Chatterjee, Soumya; Banerjee, Saumen; Nath, Manash J; Singh, Lokendra; Srivastava, Ravi B; Sarma, Hari P

    2011-02-01

    Distribution of arsenic (As) and its compound and related toxicology are serious concerns nowadays. Millions of individuals worldwide are suffering from arsenic toxic effect due to drinking of As-contaminated groundwater. The Bengal delta plain, which is formed by the Ganga-Padma-Meghna-Brahmaputra river basin, covering several districts of West Bengal, India, and Bangladesh is considered as the worst As-affected alluvial basin. The present study was carried out to examine As contamination in the state of Assam, an adjoining region of the West Bengal and Bangladesh borders. Two hundred twenty-two groundwater samples were collected from shallow and deep tubewells of six blocks of Golaghat district (Assam). Along with total As, examination of concentration levels of other key parameters, viz., Fe, Mn, Ca, Na, K, and Mg with pH, total hardness, and SO[Formula: see text], was also carried out. In respect to the permissible limit formulated by the World Health Organization (WHO; As 0.01 ppm, Fe 1.0 ppm, and Mn 0.3 ppm for potable water), the present study showed that out of the 222 groundwater samples, 67%, 76.4%, and 28.5% were found contaminated with higher metal contents (for total As, Fe, and Mn, respectively). The most badly affected area was the Gamariguri block, where 100% of the samples had As and Fe concentrations above the WHO drinking water guideline values. In this block, the highest As and Fe concentrations were recorded 0.128 and 5.9 ppm, respectively. Tubewell water of depth 180±10 ft found to be more contaminated by As and Fe with 78% and 83% of the samples were tainted with higher concentration of such toxic metals, respectively. A strong significant correlation was observed between As and Fe (0.697 at p<0.01), suggesting a possible reductive dissolution of As-Fe-bearing minerals for the mobilization of As in the groundwater of the region.

  12. Spatial distribution of persistent organic pollutants in the surface water of River Brahmaputra and River Ganga in India.

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    Chakraborty, Paromita; Sakthivel, S; Kumar, Bhupander; Kumar, Sanjay; Mishra, Meenu; Verma, V K; Gaur, Richa

    2014-01-01

    Persistent organic pollutants (POPs) like organochlorine pesticides (OCPs), polychlorinated biphenyles (PCBs) and polyaromatic hydrocarbons (PAHs) are discharged in surface water by various point and nonpoint sources thereby degrading the functioning of the ecosystem and threatening human health. Chlorinated pesticides such as Hexachlorocyclohexane (HCHs) and Dichlorodiphenyltrichloroethane (DDTs) are effective pest control chemicals, used in agriculture and public health activities (malaria eradication, etc.) in India for the past several decades and are still in use. POPs can cause endocrine disruption and food chain biomagnification because of their lipophilicity and environmental persistence. This study aims to assess the environmental occurrence and spatial distribution of OCPs, PAHs and PCBs in the surface water of River Brahmaputra and Ganga ending at the of the Bay of Bengal.The order of organochlorine pesticides is as: heptachlor>HCHs>DDTs>dieldrin>aldrin>endosulfan. Diamond Harbour and Bakkhali were the two places with elevated level of all individual HCH isomers compared to all other sites. β-Endosulfan and α-Endosulfan were high at Dibrugarh than other sampling sites. This is due to the ongoing use of Endosulfan in the tea estates in Assam especially the estates close to the town of Dibrugarh. p,p'-DDT and o,p'-DDT levels indicate the fresh input of DDT in all the sampling sites. Heptachlor has been observed in 57% of the total samples reported in the present study.These reasons may attribute to high deposition of pesticides in the surface water of Ganga and Brahmaputra.In addition the catchments area of the Ganga River is surrounded by agricultural lands so a relatively higher residue of pesticides was prevalent. Σ27 PCBs varied from BDL to 142 (Avg±SD, 3.96±6.71) ng L-1. PCB-18, PCB-52 & PCB-44 showed the highest concentration levels for all the sampling sites. PCB-126 was observed in samples taken from sites close to the city limit of Kolkata

  13. Post-glacial climate forcing of surface processes in the Ganges-Brahmaputra river basin and implications for carbon sequestration

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    Hein, Christopher J.; Galy, Valier; Galy, Albert; France-Lanord, Christian; Kudrass, Hermann; Schwenk, Tilmann

    2017-11-01

    Climate has been proposed to control both the rate of terrestrial silicate weathering and the export rate of associated sediments and terrestrial organic carbon to river-dominated margins - and thus the rate of sequestration of atmospheric CO2 in the coastal ocean - over glacial-interglacial timescales. Focused on the Ganges-Brahmaputra rivers, this study presents records of post-glacial changes in basin-scale Indian summer monsoon intensity and vegetation composition based on stable hydrogen (δD) and carbon (δ13C) isotopic compositions of terrestrial plant wax compounds preserved in the channel-levee system of the Bengal Fan. It then explores the role of these changes in controlling the provenance and degree of chemical weathering of sediments exported by these rivers, and the potential climate feedbacks through organic-carbon burial in the Bengal Fan. An observed 40‰ shift in δD and a 3-4‰ shift in both bulk organic-carbon and plant-wax δ13C values between the late glacial and mid-Holocene, followed by a return to more intermediate values during the late Holocene, correlates well with regional post-glacial paleoclimate records. Sediment provenance proxies (Sr, Nd isotopic compositions) reveal that these changes likely coincided with a subtle focusing of erosion on the southern flank of the Himalayan range during periods of greater monsoon strength and enhanced sediment discharge. However, grain-size-normalized organic-carbon concentrations in the Bengal Fan remained constant through time, despite order-of-magnitude level changes in catchment-scale monsoon precipitation and enhanced chemical weathering (recorded as a gradual increase in K/Si* and detrital carbonate content, and decrease in H2O+/Si*, proxies) throughout the study period. These findings demonstrate a partial decoupling of climate change and silicate weathering during the Holocene and that marine organic-carbon sequestration rates primary reflect rates of physical erosion and sediment export

  14. Additional record of Batasio merianiensis (Chaudhuri 1913, a catfish (Teleostei: Bagridae in upper Brahmaputra River drainage in Arunachal Pradesh, India

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    L. Tamang

    2014-05-01

    Full Text Available This paper communicates the extension of the distribution range of Batasio merianiensis in Sille River in the upper Brahmaputra drainage, East Siang District, Arunachal Pradesh. Detailed examinations of the specimens revealed existence of few morphological variations against those reported by Heok Hee Ng in 2009 on the following characteristics: by having a longer preanal (70.4-73.4 vs. 66.3-68.2% SL; a longer prepectoral (25.1-29.3 vs. 21.4-25.7% SL; a longer adipose-fin base (22.0-27.6 vs. 16.9-22.2% SL; a shorter post-adipose distance (11.6-13.4 vs.13.4-15.5% SL; a deeper body at anus (depth 18.3-20.8 vs.15.2-18.4% SL and broader head (width 17.6-20.0 vs.13.5-16.2 % HL. Few additional characters of the fish are included along with brief information on its habitat. The LIPUM, the semi-traditional method of fishing in the river is identified as a major threat to this species.

  15. Fifteen Years (1993–2007 of Surface Freshwater Storage Variability in the Ganges-Brahmaputra River Basin Using Multi-Satellite Observations

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    Edward Salameh

    2017-03-01

    Full Text Available Surface water storage is a key component of the terrestrial hydrological and biogeochemical cycles that also plays a major role in water resources management. In this study, surface water storage (SWS variations are estimated at monthly time-scale over 15 years (1993–2007 using a hypsographic approach based on the combination of topographic information from Advance Spaceborne Thermal Emission and Reflection Radiometer (ASTER and Hydrological Modeling and Analysis Platform (HyMAP-based Global Digital Elevation Models (GDEM and the Global Inundation Extent Multi-Satellite (GIEMS product in the Ganges-Brahmaputra basin. The monthly variations of the surface water storage are in good accordance with precipitation from Global Precipitation Climatology Project (GPCP, river discharges at the outlet of the Ganges and the Brahmaputra, and terrestrial water storage (TWS from the Gravity Recovery And Climate Experiment (GRACE, with correlations higher than 0.85. Surface water storage presents a strong seasonal signal (~496 km3 estimated by GIEMS/ASTER and ~378 km3 by GIEMS/HyMAPs, representing ~51% and ~41% respectively of the total water storage signal and it exhibits a large inter-annual variability with strong negative anomalies during the drought-like conditions of 1994 or strong positive anomalies such as in 1998. This new dataset of SWS is a new, highly valuable source of information for hydrological and climate modeling studies of the Ganges-Brahmaputra river basin.

  16. Attribution of the response of the stream flows of the Brahmaputra river basin of a 1.5°C warmer world

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    Saiful Islam, Akm; Mamun Rashid, Md; Allen, Myles; Mitchell, Daniel; Mohammed, Khaled; Uddin Khan, Md Jamal

    2017-04-01

    An increase in global average temperature due to climate change is likely to intensify the global hydrological cycle, which in turn will impact regional water resources. Changes of the frequency and magnitude of the precipitation patterns over a river basin will change the intensity of floods and droughts. It's still an active field of research to determine the impact of climate change on extreme events though the attribution community has been using large climate model ensembles to characterize the low signal to noise problems. After the Paris agreement of 2015, limiting the increase of the global temperature below 1.5°C was emphasized. However, it is not clear the benefits of additional half a degree reduction of temperature below 2°C which needs comprehensive scientific analysis. In this context, a collaborative effort of 39 academic and research institutions around the global is on-going to generate large ensemble simulations of climate projections under a project entitled, 'the Half a degree Additional warming, Prognosis and Projected Impacts (HAPPI)'. This study has made an attempt to conduct ensemble simulations of a hydrological model over a transboundary river basin (Brahmaputra) for estimating the changes in future extremes and mean discharges of the river forced by the climate projections generated under the HAPPI project. The Brahmaputra is a transboundary river originating in China and ending in Bangladesh and it is the fourth largest river in the world in terms of average discharge of approximately 20,000 cms. It drains water from approximately 520,000 sq.km. area of China, India, Bhutan and Bangladesh. An estimated 66 million people depend on water from this river for their livelihood through subsistence agriculture and thus any change in the river's discharge due to climate change may have a negative impact on this large population. A decrease in discharge during the dry season when the basin requires water for irrigation systems translates into a

  17. Assimilation of radar altimetry to a routing model of the Brahmaputra River

    DEFF Research Database (Denmark)

    Michailovsky, Claire Irene B.; Milzow, Christian; Bauer-Gottwein, Peter

    2013-01-01

    While satellite-based remote sensing has provided hydrologists with valuable new data sets, integration of such data sets in operational modeling systems is usually not straightforward due to spatial or temporal resolution issues or because remote sensing does not directly measure the hydrological...... quantities of interest. This is the case for satellite-based radar altimetry. River-level variations can be tracked using radar altimetry at a temporal resolution between 10 and 35 days, depending on the satellite, but hydrologists are typically interested in river flows rather than levels and require...... predictions at daily or even subdaily temporal resolutions. One way to exploit satellite radar altimetry is therefore to combine the data with hydrological models in a data assimilation framework. In this study, radar altimetry data from six ENVISAT virtual stations were assimilated to a routing model...

  18. River Modeling in Large and Ungauged Basins: Experience of Setting up the HEC RAS Model over the Ganges-Brahmaputra-Meghna Basins

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    Hossain, F.; Maswood, M.

    2014-12-01

    River modeling is the processing of setting up a physically-based hydrodynamic model that can simulate the water flow dynamics of a stream network against time varying boundary conditions. Such river models are an important component of any flood forecasting system that forecasts river levels in flood prone regions. However, many large river basins in the developing world such as the Ganges, Brahmaputra, Meghna (GBM), Indus, Irrawaddy, Salween, Mekong and Niger are mostly ungauged. Such large basins lack the necessary in-situ measurements of river bed depth/slope, bathymetry (river cross section), floodplain mapping and boundary condition flows for forcing a river model. For such basins, proxy approaches relying mostly on remote sensing data from space platforms are the only alternative. In this study, we share our experience of setting up the widely-used 1-D river model over the entire GBM basin and its stream network. Good quality in-situ measurements of river hydraulics (cross section, slope, flow) was available only for the downstream and flood prone region of the basin, which comprises only 7% of the basin area. For the remaining 93% of the basin area, we resorted to the use of data from the following satellite sensors to build a workable river model: a) Shuttle Radar Topography Mission (SRTM) for deriving bed slope; b) LANDSAT/MODIS for updating river network and flow direction generated by elevation data; c) radar altimetry data to build depth versus width relationship at river locations; d) satellite precipitation based hydrologic modeling of lateral flows into main stem rivers. In addition, we referred to an extensive body of literature to estimate the prevailing baseline hydraulics of rivers in the ungauged region. We measured success of our approach by systematically testing how well the basin-wide river model could simulate river level dynamics at two measured locations inside Bangladesh. Our experience of river modeling was replete with numerous

  19. Assessing land-use changes driven by river dynamics in chronically flood affected Upper Brahmaputra plains, India, using RS-GIS techniques

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    Nabajit Hazarika

    2015-06-01

    Full Text Available This work documents land-use changes driven by river dynamics along two tributaries in the chronically flood affected Upper Brahmaputra floodplain which supports a population of more than half a million. Planform changes for a period of 40 years are documented using topographical map and Landsat data, and the associated land-use change is assessed by utilising hybrid classification in GIS environment. Quantification of bankline migration shows that the river courses are unstable. A reversal in the rate of erosion and deposition is also observed. Hybrid classification of Landsat images yielded a higher level of accuracy as evident from the confusion matrixes. Overall, the accuracy of land-use classification ranged between 88.5% and 96.25%. Land-use change shows that there is an increase in settlement and agriculture and a decrease in the grassland. The area affected by erosion–deposition and river migration comprises primarily of the agricultural land. Effect of river dynamics on settlements is also evident. Loss of agricultural land and homestead led to the loss of livelihood and internal migration in the floodplains. The observed pattern of river dynamics and the consequent land-use change in the recent decades have thrown newer environmental challenges at a pace and magnitude way beyond the coping capabilities of the dwellers.

  20. Quantifying the individual contributions of snow and glaciers in High Mountain Asia River basins: Amu Darya, Syr Darya, Indus, Ganges, and Brahmaputra.

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    Rittger, K.; Bair, N.; Brodzik, M. J.; Racoviteanu, A.; Barrett, A.; Khalsa, S. J. S.; Raup, B. H.; Painter, T. H.; Dozier, J.; Armstrong, R. L.

    2016-12-01

    In High Mountain Asia, snow and glacier ice contribute to streamflow, but the respective contributions are not fully understood. We use daily maps of snow cover and exposed glacier ice from MODIS data at 500 m resolution as input to melt models to estimate daily snow and glacier ice contributions to streamflow. Daily maps of 1) snow over ice (SOI), 2) exposed glacier ice (EGI), and 3) snow over land (SOL) are generated using fractional snow cover, snow grain size, and annual minimum ice and snow from the MODIS-derived MODSCAG and MODICE products. Using these maps, snow and ice melt contributions are then estimated using two different melt models: a calibrated temperature-index (TI) model and an uncalibrated energy balance (EB) model (ParBal). We run the TI model over snow-covered regions of the Amu Darya, Syr Darya, Indus, Ganges, and Brahmaputra River basins. We run the EB model in sub-basins where streamflow is available and compare the EB model results to the TI model results. In the Shigar, Hunza, and Shyok sub-basins of the highly glaciated portion of the Upper Indus River basin (UIB), the EB model shows that 31%, 27%, and 20% of the surface water comes from SOI; 24%, 19%, and 15% from EGI; 44%, 49%, 48% from SOL; and 0%, 6%, and 17% from rainfall, respectively. In the less glaciated, more arid Kharmong and Astore regions, the EB model shows that 2% and 6% of surface water comes from SOI; 2% and 45% from EGI; 77% and 89% from SOL; and 19% and 0% from rainfall, respectively. In the lower elevation Tarbela sub-basin, 3% of surface water comes from SOI, 2% from EGI, 44% from SOL, and 51% from rainfall. Along with the UIB, we will present TI and EB model results in the Vakhsh sub-basin of the Amu Darya River basin and the Narayani, Sapta Kosi, and Karnali sub-basins of the Ganges River basin. Our comparisons of the TI model to the EB model show similar partitioning, but differ in timing and elevation of the melt. When moving from east to west across High Mountain

  1. Impacts of climate change and socio-economic scenarios on flow and water quality of the Ganges, Brahmaputra and Meghna (GBM) river systems: low flow and flood statistics.

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    Whitehead, P G; Barbour, E; Futter, M N; Sarkar, S; Rodda, H; Caesar, J; Butterfield, D; Jin, L; Sinha, R; Nicholls, R; Salehin, M

    2015-06-01

    The potential impacts of climate change and socio-economic change on flow and water quality in rivers worldwide is a key area of interest. The Ganges-Brahmaputra-Meghna (GBM) is one of the largest river basins in the world serving a population of over 650 million, and is of vital concern to India and Bangladesh as it provides fresh water for people, agriculture, industry, conservation and for the delta system downstream. This paper seeks to assess future changes in flow and water quality utilising a modelling approach as a means of assessment in a very complex system. The INCA-N model has been applied to the Ganges, Brahmaputra and Meghna river systems to simulate flow and water quality along the rivers under a range of future climate conditions. Three model realisations of the Met Office Hadley Centre global and regional climate models were selected from 17 perturbed model runs to evaluate a range of potential futures in climate. In addition, the models have also been evaluated using socio-economic scenarios, comprising (1) a business as usual future, (2) a more sustainable future, and (3) a less sustainable future. Model results for the 2050s and the 2090s indicate a significant increase in monsoon flows under the future climates, with enhanced flood potential. Low flows are predicted to fall with extended drought periods, which could have impacts on water and sediment supply, irrigated agriculture and saline intrusion. In contrast, the socio-economic changes had relatively little impact on flows, except under the low flow regimes where increased irrigation could further reduce water availability. However, should large scale water transfers upstream of Bangladesh be constructed, these have the potential to reduce flows and divert water away from the delta region depending on the volume and timing of the transfers. This could have significant implications for the delta in terms of saline intrusion, water supply, agriculture and maintaining crucial ecosystems such

  2. Rotifer assemblages (Rotifera: Eurotatoria of the floodplain lakes of Majuli River Island, the Brahmaputra river basin, northeast India

    Directory of Open Access Journals (Sweden)

    Bhushan Kumar Sharma

    2014-12-01

    Full Text Available Our plankton and semi-plankton collections from twelve floodplain lakes (beels of Majuli River Island, Upper Assam reveal 124 rotifer species (32 genera and 17 families; these merit biodiversity value as ~52.0% and ~30.0% of species, ~68.0 and ~45.0% of  genera and ~74.0 and ~65.0% of the families of the Phylum known from northeast India (NEI and India, respectively. Two species are new to India with Trichocerca uncinata as new record to the Oriental region.  Eleven species are new to the study area and we provide an updated list (144 species for following meta-analyses of Majuli Rotifera. Biogeographically important elements include one Australasian, four Oriental, four Palaeotropical and one cosmo (sub tropical species while several species are of regional distribution interest. The rotifer fauna is predominantly tropical and Lecanidae > Lepadellidae collectively include ~53.0% species but it records paucity of Brachionus species. Individual beels record total richness of 60-100 (77 ± 12 species, monthly richness between 24 ± 7-34 ± 7 species and maximum up to 54 species/sample. The results are characterized by high community similarities (59.7-90.4% vide Sørensen’s index, more rotifer homogeneity amongst beels, lack of any pattern of temporal richness variations and much limited influence of abiotic parameters.

  3. Stratigraphic architecture, bedload extraction, and mass balance of Holocene fluvial sediments in a tectonically subsiding basin within the Ganges-Brahmaputra River delta, Bangladesh

    Science.gov (United States)

    Sincavage, R.; Goodbred, S. L., Jr.; Pickering, J.; Wilson, C.; Paola, C.; Hossain, S.; Steckler, M. S.; Seeber, L.

    2014-12-01

    The Brahmaputra River occupied the tectonically active Sylhet Basin in eastern Bangladesh three times during the Holocene. With samples from more than 200 closely-spaced (3-5 km) boreholes, we take advantage of these discrete channel occupations and the high trapping efficiency of the subsiding basin to investigate dispersal of fluvial sediments. Experiment and theory suggest that depositional units transition from channels to lobes as transported sediment mass declines below ~30% of the total measured at the basin head. We test these ideas by reconstructing the geometry and grain size distributions of a large (30 m thick x 80 km wide) sand lobe formed during the mid-Holocene occupation (~7000-4000 years BP) of Sylhet Basin. Based on estimates of modern sediment discharge in the system, the volume of this sediment lobe is insufficient to account for the entire sediment budget. The smaller sediment volume is likely a consequence of reduced sediment discharge during a weakened monsoon. Additional sediment is likely to have also been routed out of the basin via an outlet located approximately along the modern Meghna River channel. Facies within Sylhet Basin can be characterized as stacked braidbelt sands in the proximal portion of the system, with isolated sand lenses further downstream, indicating a transition from a highly mobile braidbelt to a less mobile distributary system. The majority of bed load is extracted within a distance of ~150 km from the avulsion node, approximately coincident with the regional backwater reach of the Bengal Basin, suggesting a link between the hydraulic and "morphodynamic" backwater reaches of the system. Downstream fining is more rapid in sediments associated with the long-term occupation of Sylhet Basin, for which sediment is trapped over a relatively short distance within the sand wedge of central Sylhet Basin, than those from the early- and late-Holocene occupations, for which sediment is distributed over a longer path that follows

  4. Interannual variability of temperature in the UTLS region over Ganges-Brahmaputra-Meghna river basin based on COSMIC GNSS RO data

    Science.gov (United States)

    Khandu; Awange, Joseph L.; Forootan, Ehsan

    2016-04-01

    Poor reliability of radiosonde records across South Asia imposes serious challenges in understanding the structure of upper-tropospheric and lower-stratospheric (UTLS) region. The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) mission launched in April 2006 has overcome many observational limitations inherent in conventional atmospheric sounding instruments. This study examines the interannual variability of UTLS temperature over the Ganges-Brahmaputra-Meghna (GBM) river basin in South Asia using monthly averaged COSMIC radio occultation (RO) data, together with two global reanalyses. Comparisons between August 2006 and December 2013 indicate that MERRA (Modern-Era Retrospective Analysis for Research Application) and ERA-Interim (European Centre for Medium-Range Weather Forecasts reanalysis) are warmer than COSMIC RO data by 2 °C between 200 and 50 hPa levels. These warm biases with respect to COSMIC RO data are found to be consistent over time. The UTLS temperature show considerable interannual variability from 2006 to 2013 in addition to warming (cooling) trends in the troposphere (stratosphere). The cold (warm) anomalies in the upper troposphere (tropopause region) are found to be associated with warm ENSO (El Niño-Southern Oscillation) phase, while quasi-biennial oscillation (QBO) is negatively (positively) correlated with temperature anomalies at 70 hPa (50 hPa) level. PCA (principal component analysis) decomposition of tropopause temperatures and heights over the basin indicate that ENSO accounts for 73 % of the interannual (non-seasonal) variability with a correlation of 0.77 with Niño3.4 index whereas the QBO explains about 10 % of the variability. The largest tropopause anomaly associated with ENSO occurs during the winter, when ENSO reaches its peak. The tropopause temperature (height) increased (decreased) by about 1.5 °C (300 m) during the last major El Niño event of 2009/2010. In general, we find decreasing

  5. Quantifying the individual contributions of melt from snow and glaciers in High Mountain Asia river basins: Syr Darya, Amu Darya, Indus, Ganges, and Brahmaputra

    Science.gov (United States)

    Rittger, Karl; Bair, Edward; Racoviteanu, Adina; Brodzik, Mary J.; Armstrong, Richard L.; Jodha Khalsa, Siri; Raup, Bruce; Painter, Thomas H.; Dozier, Jeff

    2017-04-01

    Bal model in the highly glacierized Shigar, Hunza, and Shyok sub-basins of the Upper Indus River Basin (UIB) show that surface water comprises 20% to 31% SOI melt, 15% to 24% EGI melt, 44% to 49% SOL melt, and 1% to 17% rainfall. In contrast, in the less glaciated, more arid, Kharmong and Astore sub-basins of the UIB, ParBal show surface water comprises 2% to 6% SOI melt, 2% to 5% EGI melt, 77% to 89% SOL melt, and 1% to 19% rainfall. In the lower-elevation Tarbela sub-basin, nearly half of the surface water is SOL melt while the other half is rainfall. On a larger regional scale, moving from east to west across High Mountain Asia, rainfall contributions decrease and the contribution from glaciers and snow increases. We summarize contributions from melting snow and ice compared to rainfall in the Syr Darya, Amu Darya, Indus, Ganges, and Brahmaputra River basins. The method allows a systematic analysis of the annual cycle of snow and glacier ice extents over High Mountain Asia.

  6. Multivariate statistical evaluation of heavy metals in the surface water sources of Jia Bharali river basin, North Brahmaputra plain, India

    Science.gov (United States)

    Khound, Nayan J.; Bhattacharyya, Krishna G.

    2017-09-01

    The aim of this study was to assess the quality of surfacewater sources in the Jia Bharali river basin and adjoining areas of the Himalayan foothills with respect to heavy elements viz. (As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn) by hydrochemical and multivariate statistical techniques, such as cluster analysis (CA) and principal component analysis (PCA). This study presents the first ever systematic analysis on toxic elements of water samples collected from 35 different surface water sources in both the dry and wet seasons for a duration of 2 hydrological years (2009-2011). Varimax factors extracted by principal component analysis indicates anthropogenic (domestic and agricultural run-off) and geogenic influences on the trace elements. Hierarchical cluster analysis grouped 35 surfacewater sources into three statistically significant clusters based on the similarity of water quality characteristics. This study illustrates the usefulness of multivariate statistical techniques for analysis and interpretation of complex data sets, and in water quality assessment, identification of pollution sources/factors and understanding temporal/spatial variations in water quality for effective surfacewater quality management.

  7. Morphotectonic study of the Brahmaputra basin using geoinformatics

    Science.gov (United States)

    Nath Sarma, Jogendra; Acharjee, Shukla; murgante, Beniamino

    2013-04-01

    The Brahmaputra River basin occupies an area of 580,000 km2 lying in Tibet (China), Bhutan, India and Bangladesh. It is bounded on the north by the Nyen-Chen-Tanghla mountains, on the east by the Salween River basin and Patkari range of hills, on the south by Nepal Himalayas and the Naga Hills and on the west by the Ganga sub-basin. Brahmaputra river originates at an elevation of about 5150 m in south-west Tibet and flows for about 2900 km through Tibet (China), India and Bangladesh to join the Ganga.. The Brahmaputra River basin is investigated to examine the influence of active structures by applying an integrated study on geomorphology, morphotectonics, Digital Elevation Model (DEM) using topographic map, satellite data, SRTM, and seismic data. The indices for morphotectonic analysis, viz. basin elongation ratio (Re) indicated tectonically active, transverse topographic symmetry (T = 0.018-0.664) indicated asymmetric nature, asymmetric factor (AF=33) suggested tilt, valley floor width to valley height ratio (Vf = 0.0013-2.945) indicated active incision and mountain-front sinuosity (Smf = 1.11-1.68) values indicated active tectonics in the area. A great or major earthquake in the modern times, in this region may create havoc with huge loss of life and property due to high population density and rapidly developing infrastructure. Keywords: .Morphotectonic, Brahmaputra river, earthquake

  8. Significant cooling effect on the surface due to soot particles over Brahmaputra River Valley region, India: An impact on regional climate.

    Science.gov (United States)

    Tiwari, S; Kumar, R; Tunved, P; Singh, S; Panicker, A S

    2016-08-15

    Black carbon (BC) is an important atmospheric aerosol constituent that affects the climate by absorbing (directly) the sunlight and modifying cloud characteristics (indirectly). Here, we present first time yearlong measurements of BC and carbon monoxide (CO) from an urban location of Guwahati located in the Brahmaputra River valley (BRV) in the northeast region of India from 1st July 2013 to 30th June 2014. Daily BC concentrations varied within the range of 2.86 to 11.56μgm(-3) with an annual average of 7.17±1.89μgm(-3), while, CO varied from 0.19 to 1.20ppm with a mean value of 0.51±0.19ppm during the study period. The concentrations of BC (8.37μgm(-3)) and CO (0.67ppm) were ~39% and ~55% higher during the dry months (October to March) than the wet months (April to September) suggesting that seasonal changes in meteorology and emission sources play an important role in controlling these species. The seasonal ΔBC/ΔCO ratios were highest (lowest) in the pre-monsoon (winter) 18.1±1.4μgm(-3)ppmv(-1) (12.6±2.2μgm(-3)ppmv(-1)) which indicate the combustion of biofuel/biomass as well as direct emissions from fossil fuel during the pre-monsoon season. The annual BC emission was estimated to be 2.72Gg in and around Guwahati which is about 44% lower than the mega city 'Delhi' (4.86Gg). During the study period, the annual mean radiative forcing (RF) at the top of the atmosphere (TOA) for clear skies of BC was +9.5Wm(-2), however, the RF value at the surface (SFC) was -21.1Wm(-2) which indicates the net warming and cooling effects, respectively. The highest RF at SFC was in the month of April (-30Wm(-2)) which is coincident with the highest BC mass level. The BC atmospheric radiative forcing (ARF) was +30.16 (annual mean) Wm(-2) varying from +23.1 to +43.8Wm(-2). The annual mean atmospheric heating rate (AHR) due to the BC aerosols was 0.86Kday(-1) indicates the enhancement in radiation effect over the study region. The Weather Research and Forecasting model

  9. Spatial and seasonal responses of precipitation in the Ganges and Brahmaputra river basins to ENSO and Indian Ocean dipole modes: implications for flooding and drought

    Science.gov (United States)

    Pervez, Md Shahriar; Henebry, Geoffry M.

    2015-01-01

    We evaluated the spatial and seasonal responses of precipitation in the Ganges and Brahmaputra basins as modulated by the El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) modes using Global Precipitation Climatology Centre (GPCC) full data reanalysis of monthly global land-surface precipitation data from 1901 to 2010 with a spatial resolution of 0.5° × 0.5°. The GPCC monthly total precipitation climatology targeting the period 1951–2000 was used to compute gridded monthly anomalies for the entire time period. The gridded monthly anomalies were averaged for the years influenced by combinations of climate modes. Occurrences of El Niño alone significantly reduce (88% of the long-term average (LTA)) precipitation during the monsoon months in the western and southeastern Ganges Basin. In contrast, occurrences of La Niña and co-occurrences of La Niña and negative IOD events significantly enhance (110 and 109% of LTA in the Ganges and Brahmaputra Basin, respectively) precipitation across both basins. When El Niño co-occurs with positive IOD events, the impacts of El Niño on the basins' precipitation diminishes. When there is no active ENSO or IOD events (occurring in 41 out of 110 years), precipitation remains below average (95% of LTA) in the agriculturally intensive areas of Haryana, Uttar Pradesh, Rajasthan, Madhya Pradesh, and Western Nepal in the Ganges Basin, whereas precipitation remains average to above average (104% of LTA) across the Brahmaputra Basin. This pattern implies that a regular water deficit is likely, especially in the Ganges Basin, with implications for the agriculture sector due to its reliance on consistent rainfall for successful production. Historically, major droughts occurred during El Niño and co-occurrences of El Niño and positive IOD events, while major flooding occurred during La Niña and co-occurrences of La Niña and negative IOD events in the basins. This observational analysis will facilitate well

  10. Significant cooling effect on the surface due to soot particles over Brahmaputra River Valley region, India: An impact on regional climate

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, S., E-mail: smbtiwari@tropmet.res.in [Indian Institute of Tropical Meteorology, New Delhi Branch, New Delhi 110060 (India); Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm SE-10691 (Sweden); Kumar, R. [Research Application Laboratory, National Center for Atmospheric Research, Boulder, CO (United States); Tunved, P. [Department of Environmental Science and Analytical Chemistry, Stockholm University, Stockholm SE-10691 (Sweden); Singh, S. [CSIR, Central Institute of Mining & Fuel Research, Dhanbad, Jharkhand 826001 (India); Panicker, A.S. [Indian Institute of Tropical Meteorology, Pune 411008 (India)

    2016-08-15

    Black carbon (BC) is an important atmospheric aerosol constituent that affects the climate by absorbing (directly) the sunlight and modifying cloud characteristics (indirectly). Here, we present first time yearlong measurements of BC and carbon monoxide (CO) from an urban location of Guwahati located in the Brahmaputra River valley (BRV) in the northeast region of India from 1st July 2013 to 30th June 2014. Daily BC concentrations varied within the range of 2.86 to 11.56 μg m{sup −3} with an annual average of 7.17 ± 1.89 μg m{sup −3}{sub ,} while, CO varied from 0.19 to 1.20 ppm with a mean value of 0.51 ± 0.19 ppm during the study period. The concentrations of BC (8.37 μg m{sup −3}) and CO (0.67 ppm) were ~ 39% and ~ 55% higher during the dry months (October to March) than the wet months (April to September) suggesting that seasonal changes in meteorology and emission sources play an important role in controlling these species. The seasonal ΔBC/ΔCO ratios were highest (lowest) in the pre-monsoon (winter) 18.1 ± 1.4 μg m{sup −3} ppmv{sup −1} (12.6 ± 2.2 μg m{sup −3} ppmv{sup −1}) which indicate the combustion of biofuel/biomass as well as direct emissions from fossil fuel during the pre-monsoon season. The annual BC emission was estimated to be 2.72 Gg in and around Guwahati which is about 44% lower than the mega city ‘Delhi’ (4.86 Gg). During the study period, the annual mean radiative forcing (RF) at the top of the atmosphere (TOA) for clear skies of BC was + 9.5 Wm{sup −2}, however, the RF value at the surface (SFC) was − 21.1 Wm{sup −2} which indicates the net warming and cooling effects, respectively. The highest RF at SFC was in the month of April (− 30 Wm{sup −2}) which is coincident with the highest BC mass level. The BC atmospheric radiative forcing (ARF) was + 30.16 (annual mean) Wm{sup −2} varying from + 23.1 to + 43.8 Wm{sup −2}. The annual mean atmospheric heating rate (AHR) due to the BC aerosols was 0.86 K

  11. Changes and variability of precipitation and temperature in the Ganges-Brahmaputra-Meghna River Basin based on global high-resolution reanalyses

    OpenAIRE

    Khandu, .; Awange, Joseph L.; Kuhn, M.; Anyah, R.; Forootan, Ehsan

    2017-01-01

    Previous studies suggest that climate change impacts significantly on the hydro-climatic processes within the Ganges–Brahmaputra–Meghna (GBM) River Basin (RB). This study examines the observed climate characteristics and potential strengths and limitations of three global high-resolution reanalyses and satellite remote-sensing products over the GBM RB for period 1980–2013 by (1) estimating trends and interannual variations of precipitation and temperature, and (2) isolating precipitation vari...

  12. Future Visions of the Brahmaputra - Establishing Hydrologic Baseline and Water Resources Context

    Science.gov (United States)

    Ray, P. A.; Yang, Y. E.; Wi, S.; Brown, C. M.

    2013-12-01

    The Brahmaputra River Basin (China-India-Bhutan-Bangladesh) is on the verge of a transition from a largely free flowing and highly variable river to a basin of rapid investment and infrastructure development. This work demonstrates a knowledge platform for the basin that compiles available data, and develops hydrologic and water resources system models of the basin. A Variable Infiltration Capacity (VIC) model of the Brahmaputra basin supplies hydrologic information of major tributaries to a water resources system model, which routes runoff generated via the VIC model through water infrastructure, and accounts for water withdrawals for agriculture, hydropower generation, municipal demand, return flows and others human activities. The system model also simulates agricultural production and the economic value of water in its various uses, including municipal, agricultural, and hydropower. Furthermore, the modeling framework incorporates plausible climate change scenarios based on the latest projections of changes to contributing glaciers (upstream), as well as changes to monsoon behavior (downstream). Water resources projects proposed in the Brahmaputra basin are evaluated based on their distribution of benefits and costs in the absence of well-defined water entitlements, and relative to a complex regional water-energy-food nexus. Results of this project will provide a basis for water sharing negotiation among the four countries and inform trans-national water-energy policy making.

  13. Sensitivity of different satellites gridded data over Brahmaputra Basin byusing Soil and Water Assessment Tool (SWAT)

    Science.gov (United States)

    Paul, S.; Pradhanang, S. M.; Islam, A. S.

    2016-12-01

    More than half a billion people of India, China, Nepal, Bangladesh and Bhutan are dependent on the water resources of the Brahmaputra river. With climatic and anthropogenic change of this basin region is becoming a cause of concern for future water management and sharing with transboundary riparian nations. To address such issues, robust watershed runoff modeling of the basin is essential. Soil and Water Assessment Tool (SWAT) is a widely used semi-distributed watershed model that is capable of analyzing surface runoff, stream flow, water yield, sediment and nutrient transport in a large river basin such as Brahmaputra, but the performance of runoff the model depends on the accuracy of input precipitation datasets. But for a transboundary basin like Brahmaputra, precipitation gauge data from upstream areas is either not available or not accessible to the scientific communities. Satellite rainfall products are very effective where radar datasets are absent and conventional rain gauges are sparse. However, the sensitivity of the SWAT model to different satellite data products as well as hydrologic parameters for the Brahmaputra Basin are largely unknown. Thus in this study, a comparative analysis with different satellite data product has been made to assess the runoff using SWAT model. Here, datafrom three sources: TRMM, APHRDOTIE and GPCP were used as input precipitation satellite data set and ERA-Interim was used as input temperature dataset from 1998 to 2009. The main methods used in modeling the hydrologic processes in SWAT were curve number method for runoff estimating, Penman-Monteith method for PET and Muskingum method for channel routing. Our preliminary results have revealed thatthe TRMM data product is more accurate than APHRODITE and GPCP for runoff analysis. The coefficient of determination (R2) and Nash-Sutcliffe efficiencies for both calibration and validation period from TRMM data are 0.83 and 0.72, respectively.

  14. Development of seasonal flow outlook model for Ganges-Brahmaputra Basins in Bangladesh

    Directory of Open Access Journals (Sweden)

    S. Hossain

    2016-10-01

    Full Text Available Bangladesh is crisscrossed by the branches and tributaries of three main river systems, the Ganges, Bramaputra and Meghna (GBM. The temporal variation of water availability of those rivers has an impact on the different water usages such as irrigation, urban water supply, hydropower generation, navigation etc. Thus, seasonal flow outlook can play important role in various aspects of water management. The Flood Forecasting and Warning Center (FFWC in Bangladesh provides short term and medium term flood forecast, and there is a wide demand from end-users about seasonal flow outlook for agricultural purposes. The objective of this study is to develop a seasonal flow outlook model in Bangladesh based on rainfall forecast. It uses European Centre for Medium-Range Weather Forecasts (ECMWF seasonal precipitation, temperature forecast to simulate HYDROMAD hydrological model. Present study is limited for Ganges and Brahmaputra River Basins. ARIMA correction is applied to correct the model error. The performance of the model is evaluated using coefficient of determination (R2 and Nash–Sutcliffe Efficiency (NSE. The model result shows good performance with R2 value of 0.78 and NSE of 0.61 for the Brahmaputra River Basin, and R2 value of 0.72 and NSE of 0.59 for the Ganges River Basin for the period of May to July 2015. The result of the study indicates strong potential to make seasonal outlook to be operationalized.

  15. Impact of climate change on the stream flow of the lower Brahmaputra: Trends in high and low flows based on discharge-weighted ensemble modelling

    NARCIS (Netherlands)

    Gain, A.K.; Immerzeel, W.W.; Sperna Weiland, F.C.; Bierkens, M.F.P.

    2011-01-01

    Climate change is likely to have significant effects on the hydrology. The Ganges-Brahmaputra river basin is one of the most vulnerable areas in the world as it is subject to the combined effects of glacier melt, extreme monsoon rainfall and sea level rise. To what extent climate change will impact

  16. Differential heating in the Indian Ocean differentially modulates precipitation in the Ganges and Brahmaputra basins

    Science.gov (United States)

    Pervez, Md Shahriar; Henebry, Geoffrey M.

    2016-01-01

    Indo-Pacific sea surface temperature dynamics play a prominent role in Asian summer monsoon variability. Two interactive climate modes of the Indo-Pacific—the El Niño/Southern Oscillation (ENSO) and the Indian Ocean dipole mode—modulate the amount of precipitation over India, in addition to precipitation over Africa, Indonesia, and Australia. However, this modulation is not spatially uniform. The precipitation in southern India is strongly forced by the Indian Ocean dipole mode and ENSO. In contrast, across northern India, encompassing the Ganges and Brahmaputra basins, the climate mode influence on precipitation is much less. Understanding the forcing of precipitation in these river basins is vital for food security and ecosystem services for over half a billion people. Using 28 years of remote sensing observations, we demonstrate that (i) the tropical west-east differential heating in the Indian Ocean influences the Ganges precipitation and (ii) the north-south differential heating in the Indian Ocean influences the Brahmaputra precipitation. The El Niño phase induces warming in the warm pool of the Indian Ocean and exerts more influence on Ganges precipitation than Brahmaputra precipitation. The analyses indicate that both the magnitude and position of the sea surface temperature anomalies in the Indian Ocean are important drivers for precipitation dynamics that can be effectively summarized using two new indices, one tuned for each basin. These new indices have the potential to aid forecasting of drought and flooding, to contextualize land cover and land use change, and to assess the regional impacts of climate change.

  17. Hydroclimatic sustainability assessment of changing climate on cholera in the Ganges-Brahmaputra basin

    Science.gov (United States)

    Nasr-Azadani, Fariborz; Khan, Rakibul; Rahimikollu, Javad; Unnikrishnan, Avinash; Akanda, Ali; Alam, Munirul; Huq, Anwar; Jutla, Antarpreet; Colwell, Rita

    2017-10-01

    The association of cholera and climate has been extensively documented. However, determining the effects of changing climate on the occurrence of disease remains a challenge. Bimodal peaks of cholera in Bengal Delta are hypothesized to be linked to asymmetric flow of the Ganges and Brahmaputra rivers. Spring cholera is related to intrusion of bacteria-laden coastal seawater during low flow seasons, while autumn cholera results from cross-contamination of water resources when high flows in the rivers cause massive inundation. Coarse resolution of General Circulation Model (GCM) output (usually at 100 - 300 km)cannot be used to evaluate variability at the local scale(10-20 km),hence the goal of this study was to develop a framework that could be used to understand impacts of climate change on occurrence of cholera. Instead of a traditional approach of downscaling precipitation, streamflow of the two rivers was directly linked to GCM outputs, achieving reasonable accuracy (R2 = 0.89 for the Ganges and R2 = 0.91 for the Brahmaputra)using machine learning algorithms (Support Vector Regression-Particle Swarm Optimization). Copula methods were used to determine probabilistic risks of cholera under several discharge conditions. Key results, using model outputs from ECHAM5, GFDL, andHadCM3for A1B and A2 scenarios, suggest that the combined low flow of the two rivers may increase in the future, with high flows increasing for first half of this century, decreasing thereafter. Spring and autumn cholera, assuming societal conditions remain constant e.g., at the current rate, may decrease. However significant shifts were noted in the magnitude of river discharge suggesting that cholera dynamics of the delta may well demonstrate an uncertain predictable pattern of occurrence over the next century.

  18. DNA barcoding of Amblyceps congeners (Siluriformes: Amblycipitidae) from Brahmaputra drainage in northeast India.

    Science.gov (United States)

    Amin Laskar, Boni; Kumar, Vikas; Darshan, Achom; Kundu, Shantanu; Narayan Das, Debangshu

    2017-09-01

    The genus Amblyceps is recognized with 18 valid species inhabiting in fast flowing rivers mostly in South and Southeast Asia. We generated 10 mtCOI sequences for four species of Amblyceps from Brahmaputra River drainage that along with conspecific database sequences were analysed in MEGA and Mr. Bayes while Automatic Barcode Gap Discover (ABGD) was performed at web interface. Lowest between species K2P ranged from 8.7% to 16.4% compared to highest within species K2P of only 2.2%. Molecular data clearly delineated studied Amblyceps congeners into four distinct species by all the three methods of analysis employed that was congruent with the morphology based identification at species level, except a minor morphological variation observed for A. mangois specimens. Our results agree with the recent resurrection of A. arunchalensis from synonym of A. mangois. We provide three new sequences for A. laticeps and identified a mislabelled sequence of A. apangi in database.

  19. FLOOD PLAIN EVALUATION IN THE GANGA-BRAHMAPUTRA ...

    African Journals Online (AJOL)

    Dr Osondu

    2011-09-12

    Sep 12, 2011 ... Abstract. The world's largest Ganga-Brahmaputra Delta has been characterized by an interesting and complicated ... up and the tectonic events and their influence on the geomorphic features particularly the flood-plain have been thoroughly ..... unparalleled by any pestilence save that which destroyed ...

  20. Impact of Ganges–Brahmaputra interannual discharge variations on ...

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Earth System Science; Volume 120; Issue 5. Impact of Ganges–Brahmaputra interannual discharge variations on Bay of Bengal salinity and temperature during 1992–1999 period. Fabien Durand Fabrice Papa Atiqur Rahman Sujit Kumar Bala. Volume 120 Issue 5 October 2011 pp 859-872 ...

  1. Amblyceps waikhomi, a New Species of Catfish (Siluriformes: Amblycipitidae) from the Brahmaputra Drainage of Arunachal Pradesh, India

    Science.gov (United States)

    Darshan, Achom; Kachari, Akash; Dutta, Rashmi; Ganguly, Arijit; Das, Debangshu Narayan

    2016-01-01

    Amblyceps waikhomi sp. nov. is described from the Nongkon stream which drains into the Noa Dehing River, a tributary of the Brahmaputra River, in Arunachal Pradesh, India. The new species can be distinguished from congeners (except A. torrentis) in having a deeper body depth at anus. It further differs from congeners (except A. mangois and A. serratum) in having fewer vertebrae, from A. mangois in lacking (vs. having) strongly-developed projections on the proximal lepidotrichia of the median caudal-fin rays, and in having a longer, wider, and deeper head; and from A. serratum in having a posteriorly smooth (vs. with 4–5 serrations) pectoral spine, and unequal jaw length (lower jaw longer and weakly-projecting anteriorly vs. equal upper and lower jaws). It additionally differs from A. murraystuarti, A. torrentis, A. apangi, A. laticeps, and A. cerinum in having a deeply forked (vs. emarginate or truncate) caudal fin. This species is the seventh amblycipitid species known to occur in the Ganga-Brahmaputra River system. PMID:26840400

  2. Late Holocene depositional variability and provenance in the lower Ganges-Brahmaputra delta

    Science.gov (United States)

    Flood, Rory; Barr, Iestyn; Weltje, Gert Jan; Roberson, Sam; Russell, Mark; Meneely, John; Orford, Julian

    2017-04-01

    The Sundarbans is one of the largest coastal wetland sites in the world, extending over an area of approximately one million hectares of the western delta of the Ganges and Brahmaputra (G-B) rivers. The western delta has not been directly fluvially sourced, due to the eastward shift of the Ganges. This western extent of the delta is considered abandoned with sediments derived from dominant estuary-tidal dynamics, with sediment source unknown. In this study, sediment cores from the Indian Sundarbans were examined for grain-size distributions (GSDs), mineralogy through X-ray diffraction (XRD), and geochemistry with X-ray fluorescence (XRF). Chemical weathering, transport, and hydrodynamic sorting processes all affect the internal facies composition. The West Bengal Sundarbans has been examined extensively and found to reveal intensively weathered, terrestrial sediment derived from the Ganges River. There is a predominance of quartz and mica with clay minerals, with quartz interpreted as G-B Rivers draining the Himalayas during low-relief tropical weathering. Kaolinite formation is derived from feldspar and muscovite mica with kaolinite the product of intense chemical weathering. Lithofacies through GSDs are indicative of a muddy tidal flat environment with aggradation and fining-up in sizes. Mineralogy and geochemistry has revealed that the TMF in the late Holocene is still considerably influenced by regional sedimentary provenance of the Ganges River.

  3. 10Be systematics in the Tsangpo-Brahmaputra catchment: the cosmogenic nuclide legacy of the eastern Himalayan syntaxis

    Science.gov (United States)

    Lupker, Maarten; Lavé, Jérôme; France-Lanord, Christian; Christl, Marcus; Bourlès, Didier; Carcaillet, Julien; Maden, Colin; Wieler, Rainer; Rahman, Mustafizur; Bezbaruah, Devojit; Xiaohan, Liu

    2017-08-01

    The Tsangpo-Brahmaputra River drains the eastern part of the Himalayan range and flows from the Tibetan Plateau through the eastern Himalayan syntaxis downstream to the Indo-Gangetic floodplain and the Bay of Bengal. As such, it is a unique natural laboratory to study how denudation and sediment production processes are transferred to river detrital signals. In this study, we present a new 10Be data set to constrain denudation rates across the catchment and to quantify the impact of rapid erosion within the syntaxis region on cosmogenic nuclide budgets and signals. The measured 10Be denudation rates span around 2 orders of magnitude across individual catchments (ranging from 0.03 to > 4 mm yr-1) and sharply increase as the Tsangpo-Brahmaputra flows across the eastern Himalaya. The increase in denudation rates, however, occurs ˜ 150 km downstream of the Namche Barwa-Gyala Peri massif (NBGPm), an area which has been previously characterized by extremely high erosion and exhumation rates. We suggest that this downstream lag is mainly due to the physical abrasion of coarse-grained, low 10Be concentration, landslide material produced within the syntaxis that dilutes the upstream high-concentration 10Be flux from the Tibetan Plateau only after abrasion has transferred sediment to the studied sand fraction. A simple abrasion model produces typical lag distances of 50 to 150 km compatible with our observations. Abrasion effects reduce the spatial resolution over which denudation can be constrained in the eastern Himalayan syntaxis. In addition, we also highlight that denudation rate estimates are dependent on the sediment connectivity, storage, and quartz content of the upstream Tibetan Plateau part of the catchment, which tends to lead to an overestimation of downstream denudation rates. While no direct 10Be denudation measurements were made in the syntaxis, the dilution of the upstream 10Be signal, measured in Tsangpo-Brahmaputra sediments, provides constraints on the

  4. 10Be systematics in the Tsangpo-Brahmaputra catchment: the cosmogenic nuclide legacy of the eastern Himalayan syntaxis

    Directory of Open Access Journals (Sweden)

    M. Lupker

    2017-08-01

    Full Text Available The Tsangpo-Brahmaputra River drains the eastern part of the Himalayan range and flows from the Tibetan Plateau through the eastern Himalayan syntaxis downstream to the Indo-Gangetic floodplain and the Bay of Bengal. As such, it is a unique natural laboratory to study how denudation and sediment production processes are transferred to river detrital signals. In this study, we present a new 10Be data set to constrain denudation rates across the catchment and to quantify the impact of rapid erosion within the syntaxis region on cosmogenic nuclide budgets and signals. The measured 10Be denudation rates span around 2 orders of magnitude across individual catchments (ranging from 0.03 to > 4 mm yr−1 and sharply increase as the Tsangpo-Brahmaputra flows across the eastern Himalaya. The increase in denudation rates, however, occurs  ∼  150 km downstream of the Namche Barwa–Gyala Peri massif (NBGPm, an area which has been previously characterized by extremely high erosion and exhumation rates. We suggest that this downstream lag is mainly due to the physical abrasion of coarse-grained, low 10Be concentration, landslide material produced within the syntaxis that dilutes the upstream high-concentration 10Be flux from the Tibetan Plateau only after abrasion has transferred sediment to the studied sand fraction. A simple abrasion model produces typical lag distances of 50 to 150 km compatible with our observations. Abrasion effects reduce the spatial resolution over which denudation can be constrained in the eastern Himalayan syntaxis. In addition, we also highlight that denudation rate estimates are dependent on the sediment connectivity, storage, and quartz content of the upstream Tibetan Plateau part of the catchment, which tends to lead to an overestimation of downstream denudation rates. While no direct 10Be denudation measurements were made in the syntaxis, the dilution of the upstream 10Be signal, measured in Tsangpo-Brahmaputra

  5. Rainfall runoff modelling of the Upper Ganga and Brahmaputra basins using PERSiST.

    Science.gov (United States)

    Futter, M N; Whitehead, P G; Sarkar, S; Rodda, H; Crossman, J

    2015-06-01

    There are ongoing discussions about the appropriate level of complexity and sources of uncertainty in rainfall runoff models. Simulations for operational hydrology, flood forecasting or nutrient transport all warrant different levels of complexity in the modelling approach. More complex model structures are appropriate for simulations of land-cover dependent nutrient transport while more parsimonious model structures may be adequate for runoff simulation. The appropriate level of complexity is also dependent on data availability. Here, we use PERSiST; a simple, semi-distributed dynamic rainfall-runoff modelling toolkit to simulate flows in the Upper Ganges and Brahmaputra rivers. We present two sets of simulations driven by single time series of daily precipitation and temperature using simple (A) and complex (B) model structures based on uniform and hydrochemically relevant land covers respectively. Models were compared based on ensembles of Bayesian Information Criterion (BIC) statistics. Equifinality was observed for parameters but not for model structures. Model performance was better for the more complex (B) structural representations than for parsimonious model structures. The results show that structural uncertainty is more important than parameter uncertainty. The ensembles of BIC statistics suggested that neither structural representation was preferable in a statistical sense. Simulations presented here confirm that relatively simple models with limited data requirements can be used to credibly simulate flows and water balance components needed for nutrient flux modelling in large, data-poor basins.

  6. Systematic Evaluation of Satellite-Based Rainfall Products over the Brahmaputra Basin for Hydrological Applications

    Directory of Open Access Journals (Sweden)

    Sagar Ratna Bajracharya

    2015-01-01

    Full Text Available Estimation of the flow generated in the Brahmaputra river basin is important for establishing an effective flood prediction and warning services as well as for water resources assessment and management. But this is a data scarce region with few and unevenly distributed hydrometeorological stations. Five high-resolution satellite rainfall products (CPC RFE2.0, RFE2.0-Modified, CMORPH, GSMaP, and TRMM 3B42 were evaluated at different spatial and temporal resolutions (daily, dekadal, monthly, and seasonal with observed rain gauge data from 2004 to 2006 to determine their ability to fill the data gap and suitability for use in hydrological and water resources management applications. Grid-to-grid (G-G and catchment-to-catchment (C-C comparisons were performed using the verification methods developed by the International Precipitation Working Group (IPWG. Comparing different products, RFE2.0-Modified, TRMM 3B42, and CMORPH performed best; they all detected heavy, moderate, and low rainfall but still significantly underestimated magnitude of rainfall, particularly in orographically influenced areas. Overall, RFE2.0-Modified performed best showing a high correlation coefficient with observed data and low mean absolute error, root mean square error, and multiple bias and is reasonably good at detecting the occurrence of rainfall. TRMM 3B42 showed the second best performance. The study demonstrates that there is a potential use of satellite rainfall in a data scarce region.

  7. Projections of the Ganges-Brahmaputra precipitation: downscaled from GCM predictors

    Science.gov (United States)

    Pervez, Md Shahriar; Henebry, Geoffrey M.

    2014-01-01

    Downscaling Global Climate Model (GCM) projections of future climate is critical for impact studies. Downscaling enables use of GCM experiments for regional scale impact studies by generating regionally specific forecasts connecting global scale predictions and regional scale dynamics. We employed the Statistical Downscaling Model (SDSM) to downscale 21st century precipitation for two data-sparse hydrologically challenging river basins in South Asia—the Ganges and the Brahmaputra. We used CGCM3.1 by Canadian Center for Climate Modeling and Analysis version 3.1 predictors in downscaling the precipitation. Downscaling was performed on the basis of established relationships between historical Global Summary of Day observed precipitation records from 43 stations and National Center for Environmental Prediction re-analysis large scale atmospheric predictors. Although the selection of predictors was challenging during the set-up of SDSM, they were found to be indicative of important physical forcings in the basins. The precipitation of both basins was largely influenced by geopotential height: the Ganges precipitation was modulated by the U component of the wind and specific humidity at 500 and 1000 h Pa pressure levels; whereas, the Brahmaputra precipitation was modulated by the V component of the wind at 850 and 1000 h Pa pressure levels. The evaluation of the SDSM performance indicated that model accuracy for reproducing precipitation at the monthly scale was acceptable, but at the daily scale the model inadequately simulated some daily extreme precipitation events. Therefore, while the downscaled precipitation may not be the suitable input to analyze future extreme flooding or drought events, it could be adequate for analysis of future freshwater availability. Analysis of the CGCM3.1 downscaled precipitation projection with respect to observed precipitation reveals that the precipitation regime in each basin may be significantly impacted by climate change

  8. Constraining the timing of Shillong Plateau uplift from a study of the palaeo-Brahmaputra deposits, Siwalik Group, Samdrup Jongkhar, Eastern Bhutan

    Science.gov (United States)

    Govin, G.; Najman, Y.; Grujic, D.; Van Der Beek, P.; Davenport, J.; Huyghe, P.

    2015-12-01

    The ~400 km long and two km high Shillong Plateau is the only major raised topography in the Himalayan foreland. Debates over the timing of uplift and implication for erosion-climate-tectonic couplings, strain partitioning within the Himalaya and the palaeodrainage history of the palaeo-Brahmaputra are important. Grujic et al, (2006) proposed that the uplift of the plateau has affected the exhumation of Himalayan rocks to the north in Bhutan, due to the creation of a regional climatic change in the plateau's rain shadow. By contrast, Coutand et al. (2014) suggest that the local decrease in erosion rates in the eastern Bhutan Himalaya is best explained by the decrease in overthrusting rates at 5-6 Ma, which might be potentially related to late Miocene to Pliocene changes in the India-southern Eurasia convergence partitioning, with shortening taken up by faults bounding the Shillong Plateau, i.e. by its uplift. The exhumation of the Shillong Plateau has been proposed to initiate by 8-15 Ma (Biswas et al, 2007; Clark & Bilham, 2008) whilst surface uplift, decoupled from exhumation, of Miocene (Chirouze et al 2013), Pliocene (Johnson and Nur Alam 1991; Biswas et al., 2007) and Early Quaternary (Najman et al, in review) have been proposed. Our study uses the foreland basin Siwalik sedimentary record preserved to the north of the Shillong Plateau in Bhutan, to constrain the plateau's uplift history. Provenance is characterized by U-Pb dating on detrital zircons, which allows specifically documenting an Indus-Yarlung suture-zone and therefore paleo-Brahmaputra signature. We document the timing that the palaeo-Brahmaputra was shunted north and west by the rising plateau, using this U/Pb provenance technique to detect first appearance of the river and to a minor degree the Namche Barwa syntaxe signature. The results allow to better constrain the period of uplifting of the Shillong Plateau and thus better inform the implications through a study of the palaeodrainage of the

  9. Holocene construction and evolution of the Ganges-Brahmaputra-Meghna delta: the influence of climate, eustasy, and tectonics on stratigraphic architecture and fluvial dynamics

    Science.gov (United States)

    Sincavage, R.; Goodbred, S. L., Jr.; Pickering, J.; Wilson, C.; Patrick, M. G.; Akhter, S. H.; Seeber, L.; Paola, C.; Jean-Louis, G.; Grall, C.

    2015-12-01

    The Ganges-Brahmaputra-Meghna delta (GBMD), an archetypal tidally-influenced deltaic margin, has been the subject of several multi-national, multi-institutional, and interdisciplinary field studies over the past several years, resulting in an unprecedented density of data coverage for stratigraphy, hydrodynamics, and tectonics on a scale previously only found on well-studied delta systems of other types (e.g., Nile, Mississippi, Rhine-Meuse). Using a suite of geochemical, geophysical, and lithologic data extracted from a network of over 400 shallow (course along the eastern edge of the Tista Fan and west of the modern confluence with the Ganges. Construction of the modern delta, consisting of a thick (up to 80 m) succession of fluvial and deltaic sediments, was initiated by an intensified summer monsoon, coincident with accommodation generated by rapid sea-level rise following the Younger-Dryas. Sediment delivery has been focused along three pathways associated with antecedent topography inherited from Pleistocene lowstands. Stacked channel sands are the predominant facies within the upper delta, grading to isolated sand lenses in the distal reaches of Sylhet Basin, indicative of a shift from a highly mobile braidbelt to a less mobile distributary system as bedload is extracted to deposition. Episodic avulsions of the Brahmaputra River into Sylhet Basin during the mid-Holocene have been documented using a robust radiocarbon geochronology. The volume of sediment preserved from these events is insufficient to account for the entire sediment budget based on estimates of modern discharge, likely a consequence of both a weakened mid-Holocene monsoon and bypass out of the basin. Rapid (up to 7 mm/yr) subsidence in Sylhet Basin has not acted as an attractor for channel steering during much of the Holocene. Instead, the Brahmaputra has followed the steepest descent path associated with flexural loading downstream of the hinge zone along the modern braidbelt.

  10. Shallow Sedimentary Structure of the Brahmaputra Valley Constraint from Receiver Functions Analysis

    Science.gov (United States)

    Saikia, Sowrav; Chopra, Sumer; Baruah, Santanu; Singh, Upendra K.

    2017-01-01

    In this study, receiver functions from ten Broadband seismograph stations on Cenozoic sediment formations of Brahmaputra valley and its neighboring region in northeastern part of India are determined. Receiver function traces from this region show delay in peak by 1-2.5 s and associated minor peaks with the direct P-phase peak. Based on such observation, we try to image sedimentary structure of the Brahmaputra valley plain, adjacent Shillong plateau and Himalayan foredeep region. An adapted hybrid global waveform inversion technique has been applied to extract sedimentary basin structure beneath each site. The sedimentary cover of the basin is about 0.5-6.5 km thick across the valley, 0.5-1.0 km on Shillong plateau and 2.0-5.0 km in nearby foredeep region. We have found that sedimentary thickness increases from SW to NE along the Brahmaputra valley and towards the Eastern Himalayan syntaxes. The estimated sediment thickness and S wave velocity structure agree well with the results of previous active source, gravity, and deep borehole studies carried out in this region. The thick crustal low velocity sediment cover in Brahmaputra valley is expected to amplify ground motions during earthquakes and therefore important for seismic hazard assessment of the region.

  11. Validating Luminescence Dating for the Ganges Brahmaputra Meghna Delta

    Science.gov (United States)

    Chamberlain, E. L.; Wallinga, J.; Reimann, T.; Goodbred, S. L., Jr.; Steckler, M. S.; Shen, Z.; Sincavage, R.

    2016-12-01

    The Ganges Brahmaputra Meghna Delta (GBMD), Bangladesh, is one of many major world deltas positioned for crises associated with 21st century sea level rise including increasingly recurrent and severe flooding from multiple sources, and strain on infrastructure and livelihoods. Yet, the GBMD is unique from other deltas in that it has a wealth of fluvial sediment associated with rapid Himalaya erosion. The combination of a 1 billion tons/yr sediment flux and a relative lack of hard infrastructure, which could otherwise impede nature-based engineering, suggests that it is possible for the delta to adapt to changing base level. Successful management of the GBMD for the 21st century and beyond must utilize natural processes active in the delta to accomodate and protect its 150 million inhabitants. Establishing chronology methods for the GBMD is necessary for quantitative understanding of these geologic processes. However, dating in this delta is difficult: the GBMD has low organic preservation (i.e., low potential for radiocarbon dating) and previous studies suggest that Himalayan sands have poor luminescence properties (i.e., hampering use of luminescence dating). Here, we present the first delta-wide assessment of GBMD sediment suitability for luminescence dating, considering grain size, mineralogy, and provenance, and using samples with constrained depositional ages to validate the measurement approach. For 14 samples representing a range of sediments deposited in the last centuries (0-400 years), we find that sand-sized quartz has poor luminescence sensitivity across the delta with the exception of highly weathered, second-generation sands from the Meghna catchment. In contrast, quartz silt is found to have universally suitable luminescence characteristics including acceptable sensitivity. We show that OSL signals of these silt grains are well reset by light exposure prior to deposition, and that dating up to 24 ka should be possible. Our findings demonstrate the

  12. Food and Nutrition Security Trends, Determinants and Challenges in the Ganges-Brahmaputra Delta

    Science.gov (United States)

    Nilsen, K.; van Soesbergen, A.; Matthews, Z.; Burgess, N.

    2016-12-01

    In the last 20 years many developing countries have made considerable progress towards improving food security and nutrition. However, progress across countries and dimensions of food security have been uneven. While challenges to food security in the context of environmental and climate changes have been studied widely, limited evidence exists for their implications for food and nutrition security in tropical deltaic regions. Delta areas are particularly vulnerable to food insecurity and malnutrition due the specific environmental, climatic and human development factors affecting agricultural production and fisheries. These include coastal flooding and storm surges, deforestation, changes to river flow patterns and water tables, increased soil salinity and water quality degradation. Due to the large number of people living in deltaic regions and their importance in regional food production, there is a pressing need for a better understanding on how environmental factors affect food security and malnutrition. This study explores the potential impacts and challenges posed by environmental and climate change on food and nutrition security in the Ganges-Brahmaputra delta. This delta is one of the world's largest delta's draining land from Bangladesh, Bhutan, China, India and Nepal. The delta makes up around two thirds of the country of Bangladesh, a country facing high levels of child undernutrition, child mortality and a high number of people living under extreme poverty. By combining spatially explicit data from the 2007 and 2011 Demographic and Health Surveys (DHS) for Bangladesh with satellite remote sensing data (Normalised Difference Vegetation Index) for relevant growing seasons of rice, the strength of association between this climate related environmental variable and indicators of child nutrition (wasting and stunting) in the delta were evaluated. Our results show that NDVI for the growing season of rice can be used to determine trends in rice production

  13. Chronological trends in maximum and minimum water flows of the Teesta River, Bangladesh, and its implications

    OpenAIRE

    Md. Sanaul H. Mondal; Md Serajul Islam

    2017-01-01

    Bangladesh shares a common border with India in the west, north and east and with Myanmar in the southeast. These borders cut across 57 rivers that discharge through Bangladesh into the Bay of Bengal in the south. The upstream courses of these rivers traverse India, China, Nepal and Bhutan. Transboundary flows are the important sources of water resources in Bangladesh. Among the 57 transboundary rivers, the Teesta is the fourth major river in Bangladesh after the Ganges, the Brahmaputra and t...

  14. The development of the Ganges-Brahmaputra tidal delta plain: construction to maintenance phase changes in platform and channel morphology

    Science.gov (United States)

    Wilson, C.; Goodbred, S. L., Jr.; Hale, R. P.; Bain, R. L.

    2016-12-01

    The lower Ganges-Brahmaputra (G-B) delta can be divided into the fluvial-tidal river mouth and distributaries under active construction by the G-B rivers, and the distal tidally maintained deltaplain. In the active river-mouth, distributaries have constructed 5,000 km2 of large, coalescing islands that define the prograding coastline and subaerial-delta front. Although seasonal riverbank erosion is common, the area as a whole has gained land, primarily via horizontal and vertical accretion of intertidal mudflats and seaward progradation of emergent, tidally-elongated sandy channel-mouth bars. An analysis of historical imagery within the active river mouth shows larger and higher order channels form as merging bars and shoal-islands constrict distributary channels, while lower order creeks emerge secondarily, presumably as flow on shoaling intertidal mudflats becomes channelized and mangrove vegetation takes hold. With waning fluvial input (occurring from major distributary migration or avulsion), tidal and marine processes exhibit a stronger control on sediment transport and distribution, as is happening in the downdrift areas of the G-B tidal delta plain. The relatively pristine Sundarbans mangrove forest covers 4,100 km2 along the coast, while 11,200 km2 of the lower tidal delta plain is densely inhabited (population density up to 1,000/km2) and embanked for agricultural purposes. Although considered moribund or abandoned from direct fluvial sediment input, distal portions of the tidal delta are connected to the sediment transport system by its dense network of tidal channels. The subaerial landscape that was initially constructed by the point-sourced input of coarser-grained fluvial sediment from the mainstem rivers is thereafter maintained predominantly by onshore tidal sediment transport of finer-grained silt, and we observe accretion rates as high as 2-4 cm/y supported on the mangrove platform during the monsoon season. The tidal channels show evidence of

  15. Updating river basin models with radar altimetry

    DEFF Research Database (Denmark)

    Michailovsky, Claire Irene B.

    of historical discharge data. For the few VS where in-situ data was available for comparison, the discharge estimates were found to be within 4.1 to 13.8% of mean annual gauged amplitude. One of the main obstacles to the use of RA in hydrological applications is the low temporal resolution of the data which has...... suited for use in data assimilation frameworks which combine the information content from models and current observations to produce improved forecasts and reduce prediction uncertainty. The focus of the second and third papers of this thesis was therefore the use of radar altimetry as update data...... studies: the Brahmaputra and Zambezi River basins. In the Brahmaputra, data from 6 Envisat VS located along the main reach was assimilated. The assimilation improved model performance with Nash-Sutcliffe model efficiency increasing from 0.78 to 0.84 at the outlet of the basin. In the Zambezi River basin...

  16. Chemical fluxes from time series sampling of the Irrawaddy and Salween Rivers, Myanmar

    OpenAIRE

    Chapman, Hazel; Bickle, Mike; Thaw, San Hla; Thiam, Hrin Nei

    2015-01-01

    The Irrawaddy and Salween rivers in Myanmar deliver water fluxes to the ocean equal to ~ 70% of the Ganges–Brahmaputra river system. Together these systems are thought to deliver about half the dissolved load from the tectonically active Himalayan–Tibetan orogen. Previously very little data was available on the dissolved load and isotopic compositions of these major rivers. Here we present time series data of 171 samples collected fortnightly at intervals throughout 2004 to 2007 from the Irra...

  17. Influence of Ganges-Brahmaputra Discharge on the Variability of Salinity Observed Along the East Coast of India.

    Science.gov (United States)

    Gaign, L.; Chaitanya, A. V. S.

    2016-02-01

    The Bay of Bengal (BoB) is unique amongst tropical oceans, being a semi-enclosed basin that receives a very large influx of freshwater through strong summer monsoon rainfall and runoff from the Ganga-Brahmaputra (GB), Irrawaddy and Indian peninsular rivers. To date, the paucity of salinity data has prevented a thorough description of the spreading of this freshwater into the Bay. The potential impact of the salinity on cyclones and regional climate in the Bay of Bengal is however a strong incentive for a better description of the water cycle in this region. Since May 2005, the CSIR-NIO conducts a program in which fishermen collect coastal seawater samples every 5 days at eight stations scattered along the Indian coastline. This new dataset reveals a seasonal salinity drop of more than 10 g kg-1 in the northern BoB at the end of the summer monsoon. This freshening signal originates from GB outflow and propagates southward as a narrow ( 100 km wide) strip along the eastern coast of India, before reaching the southern tip of India after 2.5 months. The southward propagation of the freshwater along the coast is consistent with transport by the southward flowing East Indian Coastal current, while other processes are at stake in the ensuing erosion of this coastal freshening. This seasonal evolution has been consistently observed year after year since 2005. Beyond this climatological picture, the year-to-year anomalies of GB runoff also have a distinct influence on the coastal salinity in the northernmost part of the basin.

  18. Challenges and Approaches in River Delta Planning - report on training workshop

    NARCIS (Netherlands)

    Wosten, J.H.M.; Douven, W.; Long Phi, H.; Fida Abdullah Khan, M.

    2012-01-01

    River delta’s, like the Mekong Delta (Vietnam), Ganges-Brahmaputra Delta (Bangladesh), Irrawady (Myanmar) and Ciliwung Delta (Indonesia) are developing rapidly and characterized by large-scale urbanization and industrialization processes. They are facing serious planning challenges related to issues

  19. Geomorphology and Landscape Evolution Model for the natural and human-impacted regions of the Ganges-Brahmaputra-Meghna Delta

    Science.gov (United States)

    Wilson, C.; Goodbred, S. L.; Wallace Auerbach, L.; Ahmed, K.; Paola, C.; Reitz, M. D.; Pickering, J.

    2013-12-01

    The Ganges-Brahmaputra-Meghna delta (GBMD) in south Asia is generally considered a tide-dominated system, but much of the subaerial delta plain is geomorphically similar to river-dominated systems such as the Mississippi River delta, with a well-developed distributary network separated by low-lying, organic-rich interdistributary basins. By contrast, the lower GBMD is dominated by tidal processes and comprises a 100-km wide coastal plain with dense, interconnected tidal channels that are amalgamated to the seaward edge of the river-dominated portion of the delta. These distinct river- and tide-dominated geomorphic regions are simultaneously sustained by the enormous sediment load of the GBM rivers and its efficient dispersal via the distributary channel network and onshore advection by tides. Together these processes have resulted in the ability of the GBMD to keep pace with sea-level rise throughout the Holocene, with comparatively little shoreline transgression. However, topographic data from the Shuttle Radar Topography Mission (SRTM) highlight low-lying regions of the delta that are located at the interface of the river- and tide-dominated portions of the delta, where the transport energy of small distributaries and the upper tidal zone go to zero. As a result, these are the most sediment-starved regions of the delta and those most at risk to flooding by the summer monsoon and storm surges. Compounding the slow rates of sedimentation and high local organic content, these regions have been strongly affected by the construction of embankments (polders) that artificially de-water the soils and accelerate organic decomposition during the dry season, and further starve the land surface of sediment. Here, we present an integrated conceptual model for the geomorphic evolution of the GBMD that incorporates river- and tide-dominated regions in conjunction with channel-avulsion processes and delta-lobe construction. Each of these is also overprinted by tectonic

  20. Brahmaputra river basin groundwater: Solute distribution, chemical evolution and arsenic occurrences in different geomorphic settings

    Directory of Open Access Journals (Sweden)

    Swati Verma

    2015-09-01

    New hydrological insights for the region: Most groundwater solutes of RCD and YA terrains were derived from both silicate weathering and carbonate dissolution, while silicate weathering process dominates the solute contribution in OA groundwater. Groundwater samples from all terrains are postoxic with mean pe values between Fe(III and As(V–As(III reductive transition. While, reductive dissolution of (Fe–MnOOH is the dominant mechanism of As mobilization in RCD and YA aquifers, As in OA and PD aquifers could be mobilized by combined effect of pH dependent sorption and competitive ion exchange. The present study focuses on the major ion chemistry as well as the chemistry of the redox sensitive solutes of the groundwater in different geomorphic settings and their links to arsenic mobilization in groundwater.

  1. Rotifera diversity of a floodplain lake of the Brahmaputra river basin of lower Assam, Northeast India

    Directory of Open Access Journals (Sweden)

    Sharma, B.K.

    2012-07-01

    Full Text Available This study analyzed diversity and ecology of planktonic Rotifera of Ghorajan beel, a floodplain lake of the Brahmaputrariver basin of lower Assam region of Northeast India. Plankton samples collected (January–December, 2010 fromlittoral (station 1 and semi-limnetic regions (station 2 of this tropical wetland revealed a fairly rich rotifer fauna (84 and 80species with distinct variations (range, average ± SD in monthly richness (35–55, 46±6 and 24–54, 36±5 species andcommunity similarities (46.6–80.4 and 37.0–95.9 % at both sampling stations. The richness followed unclear annual patterns.The rotifers mainly contributed (53.3±5.1 and 55.6± 3.6 % to zooplankton abundance variations and showed high abundancefrom June through November at both stations. Brachionidae > Lecanidae exhibited high number of individuals; Asplanchnidaeand Flosculariidae were also quantitatively important families; specifically, Asplanchna priodonta, Sinantherina socialis, Brachionusfalcatus and Lecane bulla were important species for their abundance. Single abiotic factors exerted a more limited influence on richness than on abundance. Canonical correspondence analysis (CCA explained 55.6 % and 59.5 % cumulative variance of the rotifer assemblages along axis 1 and 2, respectively; the CCA indicated the importance of transparency and rainfall at station 1, and of transparency, dissolved oxygen and rainfall at station 2. Consequently, the littoral and semi-limnetic stations are characterized by micro-environmental differences.

  2. Spatial Pattern and Variation in Literacy among the Scheduled Castes Population in the Brahmaputra Valley, Assam

    Directory of Open Access Journals (Sweden)

    Dr Momita Goswami Barooah

    2014-06-01

    Full Text Available Scheduled Caste (SC population constitutes a sizeable portion of the total population of Assam accounting for 6.32 per cent according to the 2011 Census. They comprise a socially backward class in the Indian society—downtrodden illiterate people of the Indian social fabric. Literacy and educational attainment are considered the hallmark of a modern society. The traits of the modern society, such as, industrialisation, modernisation and urbanisation are closely associated with the level of literacy and education. In the middle part of the 20th century, the literacy rate among them was very low. However, in the later part of the 20th century and in the current millennium due to the developmental measures implemented by both the Central as well as State Governments of India and due to the influence of mass media, there has been a change in the pattern of literacy. The literacy rate of the SC population in the Brahmaputra Valley, Assam was 66.34 per cent in 2011 against 61.15 per cent for general population, which is slightly lower than the SC population in the Valley. The study of the pattern of literacy among various social groups of SCs in the study area provides an insight into the socio-economic situations. An attempt has been made in this paper to analyse the spatial pattern of literacy and its variations among the scheduled caste population in the Brahmaputra Valley, Assam.

  3. Constraining the timing of exhumation of the Eastern Himalayan syntaxis, from a study of the palaeo-Brahmaputra deposits, Siwalik Group, Arunachal Pradesh, India

    Science.gov (United States)

    Govin, Gwladys; Najman, Yani; van der Beek, Peter; Millar, Ian; Bernet, Matthias; Dupont-Nivet, Guillaume; Wijbrans, Jan; Gemignani, Lorenzo; Vögeli, Natalie; Huyghe, Pascale

    2015-04-01

    The evolution of Himalayan syntaxes is debated: they have been subjected to anomalously young (controlling influences, from lithospheric channel flow, to tectonic-surface process interactions. Ductile extrusion of weak lower crust from beneath Tibet by "channel flow" 5 is a process that has been proposed to account for the outward growth of the plateau to the east 6, exhumation of the Higher Himalaya in the Miocene when coupled with high erosion rates, and could be responsible for rapid exhumation of the syntaxis 7. Ehlers and Bendick 8 propose that initiation of rapid and localised exhumation at subduction arc terminations may result from the 3D geometry imposed by subducting curved shells at such locations. Clark and Bilham 9 evoke a change in regional stress along the India-Asia-Burma plate boundary, perhaps due to the introduction of denser (oceanic and transitional crust) material into the eastern part of the boundary late in the orogen's history. Zeitler et al 10 consider that exhumation of the syntaxis is driven by surface processes. In order to understand how and why the syntaxis formed, this project aims to better constrain the onset of exhumation of the Namche Barwa using the proximal detrital record of material eroded from the syntaxis by the paleo-Brahmaputra. We analyse the sedimentary record to have access to earlier erosion products than preserved in the bedrock itself, in a proximal location. The Remi River section, in the Siwalik Group, is located directly downstream of the syntaxis and therefore is the most likely location to contain these sediments. Sediment provenance is characterized by U-Pb dating on detrital zircons, which allows specifically documenting an Indus-Yarlung suture-zone (and therefore paleo-Brahmaputra) provenance. Detrital U-Pb rutile, zircon fission track and Ar/Ar mica dating is used to document rapid exhumation. When ages of the youngest population for all analysis types are essentially the same (stacked thermochronological

  4. Post-Glacial Climate Forcing of Surface Processes in the Ganges-Brahmaputra Basin and Implications for the Global Carbon Cycle

    Science.gov (United States)

    Hein, C. J.; Galy, V.; France-Lanord, C.; Galy, A.; Kudrass, H. R.; Peucker-Ehrenbrink, B.

    2016-12-01

    Silicate weathering coupled with carbonate precipitation and organic carbon (OC) burial in marine sediments are the primary mechanisms sequestering atmospheric CO2 over a range of timescales. The efficiency of both processes has long been mechanistically linked to climate: increased atmospheric CO2 sequestration under warm/wet conditions acts as a negative feedback, thereby contributing to global climate regulation. Over glacial-interglacial timescales, climate has been proposed to control the export rate of terrestrial silicate weathering products and terrestrial OC to river-dominated margins, as well as the rates of chemical weathering (i.e., the efficiency of carbon sequestration). Focused on the Ganges-Brahmaputra drainage basin, this study quantifies the relative role of climate change in the efficiency of silicate weathering and OC burial following the last glacial maximum. Stable hydrogen (δD) and carbon (δ13C) isotopic compositions of terrestrial plant wax compounds preserved in the Bengal Fan channel-levee system capture variations in the strength of the Indian summer monsoon and vegetation dynamics. Specifically, a 40‰ shift in δD and a 4‰ shift in both bulk OC and plant wax δ13C values between the late glacial and mid-Holocene, followed by a return to more intermediate values during the late Holocene, correlate well with regional post-glacial paleoclimate records. Sediment provenance proxies (Sr, Nd isotopic compositions) reveal that these changes coincided with a focusing of erosion on the southern flank of the Himalayan range during periods of greater monsoon strength and enhanced sediment discharge. However, OC loading, and thus carbon burial efficiency, in the Bengal Fan remained constant through time, demonstrating the primacy of physical erosion and climate-driven sediment export in marine OC sequestration. In contrast, a gradual increase in K/Si* and Ca/Si, and decrease in H2O+/Si*, throughout the study period may demonstrate the

  5. Delta Morphodynamics Matters! Ecosystem Services, Poverty and Morphodynamic Change in the Ganges-Brahmaputra Mega-Delta

    Science.gov (United States)

    Nicholls, R. J.; Adger, N.; Allan, A.; Darby, S. E.; Hutton, C.; Matthews, Z.; Rahman, M.; Whitehead, P. G.; Wolf, J.

    2013-12-01

    The world's deltas are probably the most vulnerable type of coastal environment, and they face multiple stresses in the coming decades. These stresses include, amongst others, local drivers due to land subsidence, population growth and urbanisation within the deltas, regional drivers due to changes in catchment management (e.g. upstream land use and dam construction), as well as global climate change impacts such as sea-level rise. At the same time, the ecosystem services of river deltas support high population densities, with around 14% of the global population inhabiting deltas. A large proportion of these people experience extremes of poverty and they are therefore severely exposed to vulnerability from environmental and ecological stress and degradation. In areas close to or below the poverty boundary, both subsistence and cash elements of the economy tend to rely disproportionately heavily on ecosystem services which underpin livelihoods. Therefore, to sustainably manage delta environments they must be viewed as complex social-environmental systems where change is only partially driven by physical drivers such as sea level rise and climate change, and human-induced development activities are also critical. Here we outline a new conceptual framework for the development of methods to understand and characterise the key drivers of change in ecosystem services that affect the environment and economic status of populous deltas, focusing specifically on the Ganges-Brahmaputra-Meghna (GBM) mega-delta. The GBM delta is characterised by densely populated coastal lowlands with significant poverty, with livelihoods supported to a large extent by natural ecosystems such as the Sunderbahns (the largest mangrove forest in the world). However, the GBM delta is under severe development pressure due to many growing cities. At present the importance of ecosystems services to poverty and livelihoods is poorly understood. This is due to due to the complexity of interactions

  6. A single width-discharge regime relationship for individual threads of braided and meandering rivers from the Himalayan Foreland

    OpenAIRE

    Gaurav, Kumar; S Tandon; Devauchelle, Olivier; Sinha, Rajiv; Métivier, François

    2017-01-01

    International audience; We explore the existence of a single width-discharge regime relation for allu-vial rivers of braided and meandering patterns. The study relies on the field measurement of a channel's cross section geometry (width, depth), discharge, and grain size of 98 individual threads of braided and meandering rivers from the Ganga-Brahmaputra plains of the Himalayan Foreland. Using this data set, we show that, irrespective of the diverse climatic and geologic setting along the str...

  7. A data assimilation system combining CryoSat-2 data and hydrodynamic river models

    DEFF Research Database (Denmark)

    Schneider, Raphael; Ridler, Marc-Etienne; Godiksen, Peter Nygaard

    2017-01-01

    There are numerous hydrologic studies using satellite altimetry data from repeat-orbit missions such as Envisat or Jason over rivers. This study is one of the first examples for the combination of altimetry from drifting-ground track satellite missions, namely CryoSat-2, with a river model. Cryo......Sat-2 SARIn Level 2 data is used to improve a 1D hydrodynamic model of the Brahmaputra River in South Asia, which is based on the Saint-Venant equations for unsteady flow and set up in the MIKE HYDRO River software. After calibration of discharge and water level the hydrodynamic model can accurately...

  8. River

    Directory of Open Access Journals (Sweden)

    Morel Mathieu

    2016-01-01

    Full Text Available The OECD report “Boosting Resilience through Innovative Risk Governance” examines the efforts of OECD countries to prevent or reduce future disaster impacts, and highlights several key areas where improvements can be made. International collaboration is insufficiently utilised to address shocks that have increasingly global consequences. Institutional design plays a significant role in facilitating or hampering the engagement and investments of governmental and non-governmental stakeholders in disaster risk prevention and mitigation. To inform the design of “better” institutions, the OECD proposes the application of a diagnostic framework that helps governments identify institutional shortcomings and take actions to improve them. The goal of the case study on the Rhone River is to conduct an analysis of the progress, achievements and existing challenges in designing and implementing disaster risk reduction strategies through the Rhone Plan from a comparative perspective across a set of selected countries of this study, like Austria and Switzerland, will inform how to improve institutional frameworks governing risk prevention and mitigation. The case study will be used to identify examples of successful practice taking into account their specific country contexts, and analyse their potential for policy transfer.

  9. Inequalities in Human Well-Being in the Urban Ganges Brahmaputra Meghna Delta

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    Sylvia Szabo

    2016-06-01

    Full Text Available The recently endorsed Sustainable Development Goals (SDGs agenda unanimously agrees on the need to focus on inclusive development, the importance of eradicating extreme poverty and managing often complex human well-being impacts of rapid urban growth. Sustainable and inclusive urbanisation will accelerate progress towards the SDGs and contribute to eradicating extreme poverty. In tropical delta regions, such as the Ganges Brahmaputra Meghna delta region, urban growth and resulting intra-urban inequalities are accelerated by the impact of environmental and climate change. In this context, the present study uses the 2010 Household Income and Expenditure Survey to analyse the extent of wealth-based inequalities in human well-being in the urban delta region and the determinants of selected welfare measures. The results suggest that the extent of intra-urban inequalities is greatest in educational attainment and access to postnatal healthcare and relatively low in the occurrence of gastric disease. The paper concludes by providing policy recommendations to reduce increasing wealth inequalities in urban areas, thus contributing to sustainable development of the region.

  10. Muddy waters: International actors and transboundary water cooperation in the Ganges-Brahmaputra problemshed

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    Paula Hanasz

    2017-06-01

    Full Text Available The portion of the Ganges-Brahmaputra-Meghna mega-basin shared between Nepal, Bhutan, northern India, and Bangladesh is one of the poorest, most densely populated, ecologically vulnerable, and socially and politically unstable areas in the world. As such, reducing the potential for transboundary water conflict by increasing cooperation between riparian states has been of increasing interest to policy-makers and foreign aid donors. The World Bank-led South Asia Water Initiative (SAWI commenced in the mid-2000s. Yet, in more than a decade of existence, neither SAWI nor other international initiatives, have been able to improve transboundary water interactions between India, Nepal, Bhutan and Bangladesh. In part this is because of the sheer complexity of transboundary water governance, and in part because of contextual factors. Addressing transboundary water issues is not a priority for the riparian states; there is significant distrust between them and resentment about India’s hydro-hegemony; and bilateral, rather than multilateral, arrangements prevail. These factors make collective action both more urgent and more difficult. If they are to increase transboundary water cooperation, international actors should, among other things, resolve historical grievances; strengthen water-sharing institutions; build trust between riparian states; and work toward outcomes based on principles of water justice.

  11. Integrated assessment of social and environmental sustainability dynamics in the Ganges-Brahmaputra-Meghna delta, Bangladesh

    Science.gov (United States)

    Nicholls, R. J.; Hutton, C. W.; Lázár, A. N.; Allan, A.; Adger, W. N.; Adams, H.; Wolf, J.; Rahman, M.; Salehin, M.

    2016-12-01

    Deltas provide diverse ecosystem services and benefits for their populations. At the same time, deltas are also recognised as one of the most vulnerable coastal environments, with a range of drivers operating at multiple scales, from global climate change and sea-level rise to deltaic-scale subsidence and land cover change. These drivers threaten these ecosystem services, which often provide livelihoods for the poorest communities in these regions. The imperative to maintain ecosystem services presents a development challenge: how to develop deltaic areas in ways that are sustainable and benefit all residents including the most vulnerable. Here we present an integrated framework to analyse changing ecosystem services in deltas and the implications for human well-being, focussing in particular on the provisioning ecosystem services of agriculture, inland and offshore capture fisheries, aquaculture and mangroves that directly support livelihoods. The framework is applied to the world's most populated delta, the Ganges-Brahmaputra-Meghna Delta within Bangladesh. The framework adopts a systemic perspective to represent the principal biophysical and socio-ecological components and their interaction. A range of methods are integrated within a quantitative framework, including biophysical and socio-economic modelling and analyses of governance through scenario development. The approach is iterative, with learning both within the project team and with national policy-making stakeholders. The analysis is used to explore physical and social outcomes for the delta under different scenarios and policy choices. We consider how the approach is transferable to other deltas and potentially other coastal areas.

  12. Construction and maintenance of the Ganges-Brahmaputra-Meghna delta: linking process, morphology, and stratigraphy.

    Science.gov (United States)

    Wilson, Carol A; Goodbred, Steven L

    2015-01-01

    We present a review of the processes, morphology, and stratigraphy of the Ganges-Brahmaputra-Meghna delta (GBMD), including insights gained from detailed elevation data. The review shows that the GBMD is best characterized as a composite system, with different regions having morphologic and stratigraphic attributes of an upland fluvial fan delta; a lowland, backwater-reach delta; a downdrift tidal delta plain; and an offshore subaqueous-delta clinoform. These distinct areas of upland and lowland fluvial reaches and tidal dominance vary in time and space, and we distinguish late-Holocene phases of delta construction, maintenance, and decline similar to delta-lobe cycling in other systems. The overall stability of the GBMD landform, relative to many deltas, reflects the efficient, widespread dispersal of sediment by the large monsoon discharge and high-energy tides that affect this region. However, we do identify portions of the delta that are in decline and losing elevation relative to sea level owing to insufficient sediment delivery. These areas, some of which are well inland of the coast, represent those most at risk to the continued effect of sea-level rise.

  13. A Preliminary Assessment of Social Vulnerability in Ganga-Brahmaputra-Meghna Delta

    Science.gov (United States)

    Hazra, Sugata; Islam, Nabiul

    2017-04-01

    The Ganga-Brahmaputra-Meghna (GBM) Delta has a high population density and is exposed to rapid environmental changes making it one of the most stressed deltas in the world. The low-lying coastal areas of the Ganga-Brahmaputra-Meghna (GBM) Delta comprise 19 coastal districts of Bangladesh and two districts in India with significant land areas within 5 meters of sea level has a population of more than 50 million people at an average population density of 1100 people/km2. This population is exposed to a range of hazards such as severe cyclones, coastal erosion, and salinization, exacerbated by climate change and subsidence which imply severe stress on the resource dependent community of this region. This situation is further complicated by poverty and limited social well-being such as poor access to education/ health/ drinking water/ sanitation facilities, and lack of food and energy security. Thus assessing social vulnerability can help to understand which communities are susceptible to environmental change and guide adaptation actions to address these threats. This preliminary study aims to construct a socio-economic index by assessing the social vulnerability of coastal communities of GBM Delta taking consistent and common secondary data from the Census of India and the Bangladesh Bureau of Statisticsand applyinga Principle Component Analysis(PCA) methodology. Several statistical tests like Kaiser-Meyer-Olkin (KMO) have also been used to assess the appropriateness of using PCA. Among the selected common indicators, five major components are found to explain majority of the total variation of social vulnerability across the delta: (1) poverty, (2) dependency ratio, (3) agriculture dependency, (4) lack of sanitation and (5) existence of mud houses. The most important observation is the existence of a social vulnerability gradient across the coast. In other words, socially marginalised and vulnerable communities are found on the Delta margin in both India and

  14. Food and nutrition security trends and challenges in the Ganges Brahmaputra Meghna (GBM delta

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    Arnout van Soesbergen

    2017-09-01

    Full Text Available The population of the Ganges Brahmaputra Meghna (GBM delta is highly vulnerable to food insecurity and malnutrition due to the specific environmental, climatic and human development factors affecting agricultural production and fisheries. To better understand the impacts of climate and environmental change on food security and nutrition in this delta, this study combines spatially explicit data from the 2007 and 2011 Bangladesh Demographic and Health Survey (BDHS with a standard satellite remotely sensed vegetation greenness index (Normalised Difference Vegetation Index, NDVI, used as a proxy for rice production. The strength of association between NDVI and child nutrition in this tropical mega-delta were tested, showing correlations between two widely used indicators of child malnutrition; stunting and wasting, and deviations from a 10 year mean NDVI (anomalies for rice crop growing seasons – regarded as critical to individual children’s early lives. For children surveyed in 2007 we found that the likelihood of being stunted decreased with increased NDVI as a measure of food production. Similarly, for children surveyed in 2011, the likelihood of being wasted reduced with increased NDVI. However, regression results for stunting in 2011 and wasting in 2007 were not statistically significant. Our findings suggest that NDVI can be regarded as indicative of climatic variability and periods of low food production but is only partly successful as an indicator of climate related impacts on child nutrition in the GBM delta. Furthermore, our study highlights some of the uncertainties and challenges with linking environmental indicators such as the NDVI with household survey data across spatial and temporal scales.

  15. Holocene climatic fluctuations from Lower Brahmaputra flood plain of Assam, northeast India

    Science.gov (United States)

    Dixit, Swati; Bera, S. K.

    2012-02-01

    Pollen analysis of a 3.2-m deep sedimentary profile cored from the Dabaka Swamp, Nagaon District, Lower Brahmaputra flood plain, Assam has revealed persistent fluvial activity during 14,120-12,700 cal years BP which may be attributed to the paucity of pollen and spores with encounterance of fluvial marker taxa like Ludwigia octavalvis and Botryococcus. Later, fluvial activity was succeeded by the tropical tree savanna under cool and dry climate between 12,700 and 11,600 cal years BP corresponding to that of global Younger Dryas. Between 11,600 and 8310 cal years BP, relatively less cool and dry climate prevailed with inception of tropical mixed deciduous taxa like Shorea robusta and Lagerstroemia parviflora. This phase is further followed by a fluvial activity between 8310 and 7100 cal years BP as evidenced by trace values of pollen and spores. Fluvial activity was further succeeded by enrichment of tropical mixed deciduous forest under warm and humid climatic regime between 7100 and 1550 cal years BP which is well-matched with the peak period of the Holocene climatic optimum. However, during 1550-768 cal years BP, final settlement of tropical mixed deciduous forest occurred under increased warm and humid climate followed by deterioration in tropical mixed deciduous forest under warm and relatively dry climatic regime since 768 cal years BP onwards due to acceleration in human settlement as evidenced by Cerealia. Increase in Melastoma, Ziziphus and Areca catechu imply forest clearance at this phase. The occurrence of degraded pollen-spore along with adequate fungal elements especially, Xylaria, Nigrospora and Microthyriaceous fruiting body is suggestive of aerobic microbial digenesis of rich organic debris during sedimentation.

  16. The Planform Mobility of Large River Channel Confluences

    Science.gov (United States)

    Sambrook Smith, Greg; Dixon, Simon; Nicholas, Andrew; Bull, Jon; Vardy, Mark; Best, James; Goodbred, Steven; Sarker, Maminul

    2017-04-01

    Large river confluences are widely acknowledged as exerting a controlling influence upon both upstream and downstream morphology and thus channel planform evolution. Despite their importance, little is known concerning their longer-term evolution and planform morphodynamics, with much of the literature focusing on confluences as representing fixed, nodal points in the fluvial network. In contrast, some studies of large sand bed rivers in India and Bangladesh have shown large river confluences can be highly mobile, although the extent to which this is representative of large confluences around the world is unknown. Confluences have also been shown to generate substantial bed scours, and if the confluence location is mobile these scours could 'comb' across wide areas. This paper presents field data of large confluences morphologies in the Ganges-Brahmaputra-Meghna river basin, illustrating the spatial extent of large river bed scours and showing scour depth can extend below base level, enhancing long term preservation potential. Based on a global review of the planform of large river confluences using Landsat imagery from 1972 to 2014 this study demonstrates such scour features can be highly mobile and there is an array of confluence morphodynamic types: from freely migrating confluences, through confluences migrating on decadal timescales to fixed confluences. Based on this analysis, a conceptual model of large river confluence types is proposed, which shows large river confluences can be sites of extensive bank erosion and avulsion, creating substantial management challenges. We quantify the abundance of mobile confluence types by classifying all large confluences in both the Amazon and Ganges-Brahmaputra-Meghna basins, showing these two large rivers have contrasting confluence morphodynamics. We show large river confluences have multiple scales of planform adjustment with important implications for river management, infrastructure and interpretation of the rock

  17. Controls on the Flux, Age, and Composition of Terrestrial Organic Carbon Exported by Rivers to the Ocean

    Science.gov (United States)

    Galy, Valier; Peucker-Ehrenbrink, Bernhard; Eglinton, Timothy; Holmes, Robert; Soule, Adam; Goetz, Scott; Laporte, Nadine; Wollheim, Wilfred

    2010-05-01

    Export of organic carbon, alkalinity and silicate-derived Ca and Mg ions to the ocean exerts critical controls on the sequestration of atmospheric carbon. As this export is mediated to a significant extent by river systems, understanding processes that control transport of land-derived matter to the coastal ocean is of fundamental importance to successful models of past and future climates. Scientists from the Woods Hole Oceanographic Institution, the Woods Hole Research Center and the University of New Hampshire have formed a river research consortium that aims at investigating large river systems with a holistic approach. The National Science Foundation is funding this initiative through its Emerging Topics in Biogeochemical Cycles (ETBC) program. Our project focuses on the biogeochemistries of the Lena and Kolyma rivers in the Russian Arctic, the Yangtze river in China, the Ganges and Brahmaputra rivers in India and Bangladesh, the Congo river in central Africa as well as the Fraser river basin in western Canada. Campaign-style sampling using a uniform sampling strategy is complemented by time-series sampling that is accomplished through collaborations with scientists at local institutions such as the East China Normal University in Shanghai (Yangtze), the University of the Fraser Valley in Abbotsford (Fraser), schools and research institutions in eastern Russia (Lena and Kolyma) and the University of Nancy, France (Ganges, Brahmaputra). We combine a standardized sampling approach for organic and inorganic constituents with spatial analyzes of digital, mostly satellite-based data products with the aim of obtaining an integrated understanding of the response of river ecosystems to past, ongoing and future environmental changes. We will present first results with a special emphasis on the age of terrestrial organic carbon exported by the Ganges-Brahmaputra river system.

  18. Fish guild structure along a longitudinally-determined ecological zonation of Teesta, an eastern Himalayan river in West Bengal, India

    OpenAIRE

    Chakrabarty, M; Homechaudhuri, S.

    2014-01-01

    The Eastern Himalaya Biodiversity Hotspot contains exceptional freshwater biodiversity and ecosystems that are of vital importance to local and regional livelihoods, but these are under threat from the developmental and anthropogenic pressures arising from the 62 million people living in the area. Therefore, monitoring the riverine health and considering future conservation approach, the study of fish biodiversity plays a significant role in this region. The River Teesta in the Brahmaputra ba...

  19. Modeling of GPS velocities across the Ganges-Brahmaputra Delta - Burma Arc oblique subduction system

    Science.gov (United States)

    Steckler, M. S.; Mondal, D. R.; Akhter, S. H.; Seeber, L.; Feng, L.; Gale, J.; Howe, M.; Masson, F.; Maurin, T.; Rangin, C.

    2014-12-01

    The Burma Arc is the northward continuation of the Sumatra-Anadaman subduction zone that gave rise to the 2004 M9.3 earthquake and tsunami. Near its northern end, it is colliding with the thick sediments of the Bengal Basin. The sediments of the Ganges-Brahmaputra Delta are folded and faulted, creating a subaerial 250-km wide accretionary prism. The deformation front is blind and reaches ½ way across the delta. Whether subduction is still occurring at this highly oblique plate boundary has been hotly debated. To investigate this, we combined our 25 continuous GPS receivers in Bangladesh with the campaign network in Myanmar, processing them together with GAMIT/GLOBK. We combined this data with 28 mostly campaign GPS sites in India (Gahalaut et al., 2012) by processing using the same IGS sites and performing a Helmert transformation to place all the data in same reference frame within ITRF2008. Published Indian plate poles yield a systematic residual for Bangladeshi sites believed to be on stable India. We estimated a new pole by combining 13 Indian stations (Mahesh et al., 2013) with 2 of our stations. Due to the rapid growth of the accretionary prism and the overthrusting by the Shillong Plateau, the Burma Arc changes shape from the backstop to the front folds. To project the GPS velocities into a profile, we have experimented with several projections that vary across the foldbelt, using the arc of the earthquakes and the topography as a guide. Strike-slip is mostly absorbed by the Sagaing and CMF faults, and some additional shear is distributed over the region. The best fitting suite of models for the shortening component yield 13-15 mm/y of shortening across the arc on a shallow-dipping megathrust. Additional shortening of ~4 mm/y is absorbed in the vicinity of the Kabaw Fault, where coverage is sparse. The dip of the megathrust and the depth of its downdip end trade off with one another in the different projections. The low range of dips of 6-10° is consistent

  20. Natural attenuation processes of arsenic in the groundwater of the Brahmaputra floodplain of Assam, India.

    Science.gov (United States)

    Sailo, Lalsangzela; Mahanta, Chandan

    2016-01-01

    Natural attenuation of higher arsenic (As) concentration in the groundwater of the Brahmaputra valley of Assam can be a viable option for its remediation. The assessment of attenuation capacities in aquifers was done using three sediment core samples (namely C_50, C_70 and C_150) representing the commonly found sediments and characterized as viz. reduced, oxidized and moderately oxidized sediments, respectively. The feasability of aquifers to release low As water depends on the sorption capacity of the sediments to directly adsorbed as As(III) and/or oxidation to As(V) on oxidative sites. The various batch sorption experiments along with competition of other anions for adsorption sites at different concentrations were investigated. The sediments were observed to adsorb both As(III) and As(V) with varying magnitudes depending on the species of As, pH and concentrations of competing anions. The Elovich kinetic model best described kinetic test data. The oxidized sediment (C_70) with the highest Fe and Mn content has the highest adsorption capacity. The competition for adsorption sites with As(V) in the sediment samples followed the order PO4(3-) > SiO2 > HCO3(-). The oxidation of As(III) to As(V) by the sediments was analyzed as it is also the most effective pathway to reduce the toxicity as well as the mobility of As in the subsurface environment. Sediment C_70 showed the highest potential to oxidize As(III) to As(V) in the oxidative sites of the sediments. The removal of As(III) in the oxidative site via As(V) was the dominant As removal mechanism for the oxidized sediment (C_70) and moderately oxidized sediment (C_150) than the direct adsorption of As(III) on the adsorptive sites as on reduced sediment sample C_50. Therefore, targeting the oxidized sediment with a high concentration of Fe-oxides and Mn-oxides might make natural attenuation of As viable in the study areas.

  1. Impacts of the Indian Rivers Inter-link Project on Sediment Transport to River Deltas

    Science.gov (United States)

    Higgins, S.; Overeem, I.; Syvitski, J. P.

    2015-12-01

    The Indian Rivers Inter-link project is a proposal by the Indian government to link several of India's major rivers via a network of reservoirs and canals. Variations of the IRI have been discussed since 1980, but the current plan has recently received increased support from the Indian government. Construction on three canals has controversially begun. If the Inter-link project moves forward, fourteen canals will divert water from tributaries of the Ganges and Brahmaputra rivers to areas in the west, where fresh water is needed for irrigation. Additional canals would transport Himalayan sediments 500 km south to the Mahanadi delta and more than 1000 km south to the Godavari and Krishna deltas. We investigate the impacts of the proposed diversions on sediment transport to the Mahanadi/Brahmani, Godavari, and Krishna deltas in India and the Ganges-Brahmaputra Delta in Bangladesh. We map the entire river network and the proposed new nodes and connections. Changing watersheds are delineated using the Terrain Analysis Using Digital Elevation Models (TauDEM) Suite. Climate data comes from interpolation between observed precipitation stations located in China, Nepal, India, Bhutan and Bangladesh. Changes in water discharge due to the proposed canals are simulated using HydroTrend, a climate-driven hydrological water balance and transport model that incorporates drainage area, discharge, relief, temperature, basin-average lithology, and anthropogenic influences. Simulated river discharge is validated against observations from gauging stations archived by the Global Runoff Data Center (GRDC). HydroTrend is then used to investigate sediment transport changes that may result from the proposed canals. We also quantify changes in contributing areas for the outlets of nine major Indian rivers, showing that more than 50% of the land in India will contribute a portion of its runoff to a new outlet should the entire canal system be constructed.

  2. Satellite-derived surface and sub-surface water storage in the Ganges–Brahmaputra River Basin

    Directory of Open Access Journals (Sweden)

    Fabrice Papa

    2015-09-01

    New hydrological insights: Basin-scale monthly SWS variations for the period 2003–2007 show a mean annual amplitude of ∼410 km3, contributing to about 45% of the Gravity Recovery And Climate Experiment (GRACE-derived total water storage variations (TWS. During the drought-like conditions in 2006, we estimate that the SWS deficit over the entire GB basin in July–August–September was about 30% as compared to other years. The SWS variations are then used to decompose the GB GRACE-derived TWS and isolate the variations of SSWS whose mean annual amplitude is estimated to be ∼550 km3. This new dataset of water storage variations represent an unprecedented source of information for hydrological and climate modeling studies of the ISC.

  3. Application of CryoSat-2 altimetry data for river analysis and modelling

    Science.gov (United States)

    Schneider, Raphael; Nygaard Godiksen, Peter; Villadsen, Heidi; Madsen, Henrik; Bauer-Gottwein, Peter

    2017-02-01

    Availability of in situ river monitoring data, especially of data shared across boundaries, is decreasing, despite growing challenges for water resource management across the entire globe. This is especially valid for the case study of this work, the Brahmaputra Basin in South Asia. Commonly, satellite altimeters are used in various ways to provide information about such river basins. Most missions provide virtual station time series of water levels at locations where their repeat orbits cross rivers. CryoSat-2 is equipped with a new type of altimeter, providing estimates of the actual ground location seen in the reflected signal. It also uses a drifting orbit, challenging conventional ways of processing altimetry data to river water levels and their incorporation in hydrologic-hydrodynamic models. However, CryoSat-2 altimetry data provides an unprecedentedly high spatial resolution. This paper suggests a procedure to (i) filter CryoSat-2 observations over rivers to extract water-level profiles along the river, and (ii) use this information in combination with a hydrologic-hydrodynamic model to fit the simulated water levels with an accuracy that cannot be reached using information from globally available digital elevation models (DEMs) such as from the Shuttle Radar Topography Mission (SRTM) only. The filtering was done based on dynamic river masks extracted from Landsat imagery, providing spatial and temporal resolutions high enough to map the braided river channels and their dynamic morphology. This allowed extraction of river water levels over previously unmonitored narrow stretches of the river. In the Assam Valley section of the Brahmaputra River, CryoSat-2 data and Envisat virtual station data were combined to calibrate cross sections in a 1-D hydrodynamic model of the river. The hydrologic-hydrodynamic model setup and calibration are almost exclusively based on openly available remote sensing data and other global data sources, ensuring transferability of

  4. Where Land and River Meet: A Study of Disaster at the Riparian Zone of Majuli Island

    Science.gov (United States)

    Sahay, Avijit

    2016-04-01

    Situated on the River Brahmaputra in the Indian state of Assam, and inscribed as a Cultural Heritage site by the UNESCO, Majuli, one of the largest and most populated riverine islands in the world has for long been considered a cultural and spiritual capital of Assam. Shankerdeb, the famous 15th century social and religious reformer of Assam started the Vaishnavite cult in this island, and to this date, it is the center of Vaishnavite Hinduism in India. However, in 1950, a powerful earthquake struck the Brahmaputra Valley of Assam, turning this life giving river into a harbinger of disaster for the island. Post-earthquake, the river has been flooding and eroding the riverbank at an alarming rate. Preliminary studies have shown that between one-third to two-third area of original land has been lost to the river. This has caused a large number of its 167,304 persons to become migrants in their own land. Clearly, a human tragedy is unfolding at the site where land and river meet. The present study is an attempt to quantify this human tragedy by using Remote Sensing images and techniques to find out the exact extent of damage done by the river and to qualify the tragedy by finding out the impact of riverbank erosion on the culture, society, and economy of the island through fieldwork and primary survey.

  5. Preface to the volume Large Rivers

    Science.gov (United States)

    Latrubesse, Edgardo M.; Abad, Jorge D.

    2018-02-01

    The study and knowledge of the geomorphology of large rivers increased significantly during the last years and the factors that triggered these advances are multiple. On one hand, modern technologies became more accessible and their disseminated usage allowed the collection of data from large rivers as never seen before. The generalized use of high tech data collection with geophysics equipment such as acoustic Doppler current profilers-ADCPs, multibeam echosounders, plus the availability of geospatial and computational tools for morphodynamics, hydrological and hydrosedimentological modeling, have accelerated the scientific production on the geomorphology of large rivers at a global scale. Despite the advances, there is yet a lot of work ahead. Good parts of the large rivers are in the tropics and many are still unexplored. The tropics also hold crucial fluvial basins that concentrate good part of the gross domestic product of large countries like the Parana River in Argentina and Brazil, the Ganges-Brahmaputra in India, the Indus River in Pakistan, and the Mekong River in several countries of South East Asia. The environmental importance of tropical rivers is also outstanding. They hold the highest biodiversity of fluvial fauna and alluvial vegetation and many of them, particularly those in Southeast Asia, are among the most hazardous systems for floods in the entire world. Tropical rivers draining mountain chains such as the Himalaya, the Andes and insular Southeast Asia are also among the most heavily sediment loaded rivers and play a key role in both the storage of sediment at continental scale and the transference of sediments from the continent to the Ocean at planetary scale (Andermann et al., 2012; Latrubesse and Restrepo, 2014; Milliman and Syvitski, 1992; Milliman and Farsnworth, 2011; Sinha and Friend, 1994).

  6. Effect of lambda cyhalothrin on Calothrix sp. (GUEco 1001), an autochthonous cyanobacterium of rice fields of Brahmaputra floodplain.

    Science.gov (United States)

    Gupta, Kiran; Baruah, P P

    2015-12-01

    Pesticide contamination in the rice fields has manifested into a serious global environmental concern. Application of pesticides in the rice fields has deleterious effects on non-target organisms including nitrogen-fixing cyanobacteria which help to maintain the rice field fertility. In the present research endeavor, the effect of lambda cyhalothrin (5% EC), a synthetic pyrethroid insecticide, has been studied on the growth and pigments content of Calothrix sp. (GUEco 1001), an indigenous strain isolated from rice grown areas of Brahmaputra floodplain. To study the toxic effect of lambda cyhalothrin, the test organism was exposed to varying concentrations of the insecticide i.e., 20 ppm, 40 ppm, 80 ppm, and 160 ppm based upon the determination of LC50 for a period of 20 days. The result obtained in the laboratory showed a progressive decrease in the growth and pigments content by the test organism with increasing concentrations of the lambda cyhalothrin against time dose-dependent manner. At high dose (160 ppm), the test organism showed significant decrease in dry weight biomass (54.5%), chlorophyll-a (68%), carotenoids (38%), phycocyanin (80%), and nitrogen contents (55%) over the control. A little but insignificant stimulatory effect on growth and chlorophyll-a contents was recorded in 20 ppm treatment of the insecticide that, however, was reversed in case of carotenoids and phycocyanin contents.

  7. Application of CryoSat-2 altimetry data for river analysis and modelling

    DEFF Research Database (Denmark)

    Schneider, Raphael; Godiksen, Peter Nygaard; Villadsen, Heidi

    2017-01-01

    –hydrodynamic model setup and calibration are almost exclusively based on openly available remote sensing data and other global data sources, ensuring transferability of the developed methods. They provide an opportunity to achieve forecasts of both discharge and water levels in a poorly gauged river system.......Availability of in situ river monitoring data, especially of data shared across boundaries, is decreasing, despite growing challenges for water resource management across the entire globe. This is especially valid for the case study of this work, the Brahmaputra Basin in South Asia. Commonly......, satellite altimeters are used in various ways to provide information about such river basins. Most missions provide virtual station time series of water levels at locations where their repeat orbits cross rivers. CryoSat-2 is equipped with a new type of altimeter, providing estimates of the actual ground...

  8. A first look at the influence of anthropogenic climate change on the future delivery of fluvial sediment to the Ganges-Brahmaputra-Meghna delta.

    Science.gov (United States)

    Darby, Stephen E; Dunn, Frances E; Nicholls, Robert J; Rahman, Munsur; Riddy, Liam

    2015-09-01

    We employ a climate-driven hydrological water balance and sediment transport model (HydroTrend) to simulate future climate-driven sediment loads flowing into the Ganges-Brahmaputra-Meghna (GBM) mega-delta. The model was parameterised using high-quality topographic data and forced with daily temperature and precipitation data obtained from downscaled Regional Climate Model (RCM) simulations for the period 1971-2100. Three perturbed RCM model runs were selected to quantify the potential range of future climate conditions associated with the SRES A1B scenario. Fluvial sediment delivery rates to the GBM delta associated with these climate data sets are projected to increase under the influence of anthropogenic climate change, albeit with the magnitude of the increase varying across the two catchments. Of the two study basins, the Brahmaputra's fluvial sediment load is predicted to be more sensitive to future climate change. Specifically, by the middle part of the 21(st) century, our model results suggest that sediment loads increase (relative to the 1981-2000 baseline period) over a range of between 16% and 18% (depending on climate model run) for the Ganges, but by between 25% and 28% for the Brahmaputra. The simulated increase in sediment flux emanating from the two catchments further increases towards the end of the 21(st) century, reaching between 34% and 37% for the Ganges and between 52% and 60% for the Brahmaputra by the 2090s. The variability in these changes across the three climate change simulations is small compared to the changes, suggesting they represent a significant increase. The new data obtained in this study offer the first estimate of whether and how anthropogenic climate change may affect the delivery of fluvial sediment to the GBM delta, informing assessments of the future sustainability and resilience of one of the world's most vulnerable mega-deltas. Specifically, such significant increases in future sediment loads could increase the resilience

  9. Water quality assessment in terms of water quality index (WQI): case study of the Kolong River, Assam, India

    Science.gov (United States)

    Bora, Minakshi; Goswami, Dulal C.

    2017-10-01

    The Kolong River of Nagaon district, Assam has been facing serious degradation leading to its current moribund condition due to a drastic human intervention in the form of an embankment put across it near its take-off point from the Brahmaputra River in the year 1964. The blockage of the river flow was adopted as a flood control measure to protect its riparian areas, especially the Nagaon town, from flood hazard. The river, once a blooming distributary of the mighty Brahmaputra, had high navigability and rich riparian biodiversity with a well established agriculturally productive watershed. However, the present status of Kolong River is highly wretched as a consequence of the post-dam effects thus leaving it as stagnant pools of polluted water with negligible socio-economic and ecological value. The Central Pollution Control Board, in one of its report has placed the Kolong River among 275 most polluted rivers of India. Thus, this study is conducted to analyze the seasonal water quality status of the Kolong River in terms of water quality index (WQI). The WQI scores shows very poor to unsuitable quality of water samples in almost all the seven sampling sites along the Kolong River. The water quality is found to be most deteriorated during monsoon season with an average WQI value of 122.47 as compared to pre-monsoon and post-monsoon season having average WQI value of 85.73 and 80.75, respectively. Out of the seven sampling sites, Hatimura site (S1) and Nagaon Town site (S4) are observed to be the most polluted sites.

  10. Forecasting Flooding in the Brahmaputra and Ganges Delta of Bangladesh on Short (1-10 days), Medium (20-30 days) and Seasonal Time Scales (1-6 months)

    Science.gov (United States)

    Webster, P. J.; Hoyos, C. D.; Hopson, T. M.; Chang, H.; Jian, J.

    2007-12-01

    Following the devastating flood years of 1998 during which 60% of Bangladesh was under water for a period of 3 months, the Climate Forecast Applications in Bangladesh (CFAB) project was formed with funding by USAID and NSF which eventually resulted in a joint project with the European Centre for Medium Range Weather Forecasting (ECMWF), the Asian Disaster Preparedness Centre (ADPC) and the Bangladesh Flood Forecasting and Warning Centre. The project was organized and developed through the Georgia Institute of Technology. The aim of CFAB was to develop innovative methods of extending the warning of flooding in Bangladesh noting that there was a unique problem: India provided no upstream discharge data to Bangladesh so that before CFAB the maximum lead time of a forecast was that given by measuring river discharge at the India-Bangladesh border: no lead-time at the border and 2 days in the southern parts of the country. Given that the Brahmaputra and Ganges catchment areas had to be regarded as essentially unguaged, it was clear that innovative techniques had to be developed. On of the basic criterion was that the system should provide probabilistic forecasts in order for the Bangladeshis to assess risk. A three-tier system was developed to allow strategic and tactical decisions to be made for agricultural purposes and disaster mitigation: seasonal (1-6 months: strategic), medium range (20-30 days: strategic/tactical) and short range (1-10 days: tactical). The system that has been developed brings together for the first time operational meteorological forecasts (ensemble forecasts from ECMWF), with satellite and discharge data and a suite of hydrological models. In addition, with ADPC and FFWC we have developed an in-country forecast dispersion system that allows a rapid dissemination. The system has proven to be rather successful, especially in the short range. The flooding events of 2004 were forecast with all forecasting tiers at the respective lead time. In

  11. Ganges River dolphin: an overview of biology, ecology, and conservation status in India.

    Science.gov (United States)

    Sinha, Ravindra K; Kannan, Kurunthachalam

    2014-12-01

    Ganges River dolphin, Platanista gangetica gangetica, is one of the three obligatory freshwater dolphins in the world and is distributed in the Ganges-Brahmaputra-Meghna and Sangu-Karnaphuli River systems in India, Nepal, and Bangladesh. This species is facing considerable threats to its survival, and its population has dwindled from 4000 to 5000 in the early 1980s to 3500 in 2014 in the distribution range. This article reviews current status of the sub-species, habitat use, and the potential threats that the dolphins face for their survival (details of taxonomic status and genetics, evolutionary adaptations and anatomical peculiarities, physical adaptation, primitive characteristics, biology, behavior, surfacing behavior and dive times, mating and birth, and life span/age have been placed as Electronic Supplementary Materials). Recommendations have been made for the protection and developing strategies for the conservation of this Endangered and endemic sub-species.

  12. Assessing the impacts of climate and land use and land cover change on the freshwater availability in the Brahmaputra River basin

    Directory of Open Access Journals (Sweden)

    Md Shahriar Pervez

    2015-03-01

    New hydrological insights for the region: Basin average annual ET was found to be sensitive to changes in CO2 concentration and temperature, while total water yield, streamflow, and groundwater recharge were sensitive to changes in precipitation. The basin hydrological components were predicted to increase with seasonal variability in response to climate and land use change scenarios. Strong increasing trends were predicted for total water yield, streamflow, and groundwater recharge, indicating exacerbation of flooding potential during August–October, but strong decreasing trends were predicted, indicating exacerbation of drought potential during May–July of the 21st century. The model has potential to facilitate strategic decision making through scenario generation integrating climate change adaptation and hazard mitigation policies to ensure optimized allocation of water resources under a variable and changing climate.

  13. Hydrologic Visualization of Glacier-Driven Watersheds to Enhance Education Exchange Between Students from the US and Ganges-Brahmaputra Delta on Freshwater Sustainability

    Science.gov (United States)

    Hossain, F.

    2014-12-01

    It has been argued and demonstrated in the past that STEM outreach in the field of hydrology is effective only when it is contextualized using an actual problem that students can visualize in 'their backyard.' The Puyallup watershed, which is in the "backyard" of University of Washington (UW) and the Ganges Brahmaputra (GB) Delta (which UW Department of Civil Engineering has institutional access through an MOU with Institute of Water Modeling-IWM, Bangladesh and International Center for Integrated Mountain Development-ICIMOD, Nepal) provide an ideal opportunity to build a unique education program for US and South Asian students on global freshwater sustainability. Using a rich set of geospatial data layers, dynamic hydrologic datasets and a user-driven visualization platform called Hydro-VIZ, we present a plan on how exchange students can witness the differences in human-nature coupling of each region and share notes on the future of freshwater supply for densely-populated deltas. We discuss the development of a set of place-based learning curricular material built around two contrasting regions and the HydroVIZ platform with functionality to explore the human coupling of water sustainability.

  14. Aged dissolved organic carbon exported from rivers of the Third Pole

    Science.gov (United States)

    Qu, B.; Sillanpää, M.; Kang, S.; Stubbins, A.; Li, C.; Fangping, Y.; Aho, K. S.; Raymond, P. A.

    2016-12-01

    Global river export of dissolved organic carbon (DOC) to the oceans (250 Tg-C yr-1; Tg=1012g) is a key component of the global carbon cycle and is subject to climate forcing. Polar ecosystems are experiencing dramatic warming in the recent decades, potentially mobilizing large amounts of ancient permafrost carbon into contemporary rivers. However, no information is available for rivers of the climate sensitive Tibetan Plateau, which is the highest plateau on earth, water tower of Asia, and another region with extensive permafrost cover. We present the radiocarbon age and export of dissolved organic carbon from the Tibetan headwaters of three large Asian rivers (Yellow, Yangtze and Brahmaputra) during high flow. Dissolved organic carbon concentrations were lower than for Arctic rivers. Consequently, the carbon yield (0.41 gC m-2 yr-1) was lower than for Arctic rivers (1.6 gC m-2 yr-1), despite Tibetan rivers having higher annual discharge (280 kg m-2 yr-1 vs 215 kg m-2 yr-1). Average radiocarbon ages (511±294 years before present) were older in the Tibetan rivers than for Arctic and tropical rivers. Explanations were sought for Tibetan river carbon's old age. A positive correlation between radiocarbon age and permafrost watershed coverage was observed, indicating that old carbon (656±177 years before present) is exported during high flow from permafrost regions of the Tibetan Plateau. Additionally, Inputs of fossil carbon (2,265±1009 years before present) from polluted South and East Asia may also contribute to the old age of Tibetan river carbon.

  15. High gene flow and genetic diversity in three economically important Zanthoxylum Spp. of Upper Brahmaputra Valley Zone of NE India using molecular markers.

    Science.gov (United States)

    Medhi, K; Sarmah, D K; Deka, M; Bhau, B S

    2014-12-01

    The genetic diversity in Zanthoxylum species viz.  Zanthoxylum nitidum, Zanthoxylum oxyphyllum and Zanthoxylum rhesta collected from the Upper Brahmaputra Valley Zone of Assam (NE India) was amplified using 13 random amplified polymorphic DNA (RAPD) markers and 9 inter-simple sequence repeat (ISSR) markers. RAPD markers were able to detect 81.82% polymorphism whereas ISSR detected 98.02% polymorphism. The genetic similarities were analyzed from the dendrogram constructed by RAPD and ISSR fingerprinting methods which divided the 3 species of Zanthoxylum into 3 clear different clusters. The principle component analysis (PCA) was carried out to confirm the clustering pattern of RAPD and ISSR analysis. Analysis of molecular variance (AMOVA) revealed the presence of significant variability between different Zanthoxylum species and within the species by both RAPD and ISSR markers. Z. nitidum was found to be sharing a high degree of variation with the other two Zanthoxylum species under study. The Nei's gene diversity (h), Shannon's information index (I), observed number of alleles (na) and effective number of alleles (ne) were also found to be higher in ISSR markers (0.3526, 0.5230, 1.9802 and 1.6145) than in RAPD markers (0.3144, 0.4610, 1.8182 and 1.5571). The values for total genotype diversity for among population (HT), within population diversity (Hs) and gene flow (Nm) were more in ISSR (0.3491, 0.2644 and 1.5610) than RAPD (0.3128, 0.2264 and 1.3087) but the mean coefficient of gene differentiation (GST) was more in RAPD (0.2764) than ISSR (0.2426). A comparison of this two finger printing methods was done by calculating MR, EMI and MI. The correlation coefficient between data matrices of RAPD and ISSR based on Mantel test was found to be significant (r = 0.65612).

  16. Quaternary stratigraphy, sediment characteristics and geochemistry of arsenic-contaminated alluvial aquifers in the Ganges-Brahmaputra floodplain in central Bangladesh.

    Science.gov (United States)

    Shamsudduha, M; Uddin, A; Saunders, J A; Lee, M-K

    2008-07-29

    This study focuses on the Quaternary stratigraphy, sediment composition, mineralogy, and geochemistry of arsenic (As)-contaminated alluvial aquifers in the Ganges-Brahmaputra floodplain in the central Bangladesh. Arsenic concentrations in 85 tubewells in Manikganj area, 70 km northwest of Dhaka City, range from 0.25 microg/L to 191 microg/L with a mean concentration of 33 microg/L. Groundwater is mainly Ca-HCO(3) type with high concentrations of dissolved As, Fe, and Mn, but low level of SO(4). The uppermost aquifer occurs between 10 m and 80 m below the surface that has a mean arsenic concentration of 35 microg/L. Deeper aquifer (>100 m depth) has a mean arsenic concentration of 18 microg/L. Sediments in the upper aquifer are mostly gray to dark-gray, whereas sediments in the deep aquifer are mostly yellowing-gray to brown. Quartz, feldspar, mica, hornblende, garnet, kyanite, tourmaline, magnetite, ilmenite are the major minerals in sediments from both aquifers. Biotite and potassium feldspar are dominant in shallow aquifer, although plagioclase feldspar and garnet are abundant in deep aquifer sediments. Sediment composition suggests a mixed provenance with sediment supplies from both orogenic belts and cratons. High arsenic concentrations in sediments are found within the upper 50 m in drilled core samples. Statistical analysis shows that As, Fe, Mn, Ca, and P are strongly correlated in sediments. Concentrations of Cd, Cu, Ni, Zn, and Bi also show strong correlations with arsenic in the Manikganj sediment cores. Authigenic goethite concretions, possibly formed by bacteria, are found in the shallow sediments, which contain arsenic of a concentration as high as 8.8 mg/kg. High arsenic concentrations in aquifers are associated with fine-grained sediments that were derived mostly from the recycled orogens and relatively rapidly deposited mainly by meandering channels during the Early to Middle Holocene rising sea-level conditions.

  17. Fish guild structure along a longitudinally-determined ecological zonation of Teesta, an eastern Himalayan river in West Bengal, India

    Directory of Open Access Journals (Sweden)

    Chakrabarty, M

    2014-04-01

    Full Text Available The Eastern Himalaya Biodiversity Hotspot contains exceptional freshwater biodiversity and ecosystems that are of vital importance to local and regional livelihoods, but these are under threat from the developmental and anthropogenic pressures arising from the 62 million people living in the area. Therefore, monitoring the riverine health and considering future conservation approach, the study of fish biodiversity plays a significant role in this region. The River Teesta in the Brahmaputra basin in India forms one of the major rivers in the Eastern Himalayas. In the present investigation, we studied ecological fish guilds as they can enhance the usefulness of fish zonation concepts and serve as tools to assess and manage the ecological integrity of large rivers. We classified fish species according to their water flow preference and spawning substrate preference. Ten spawning habitats were identified, occurring in three water flow guilds. The most widely preferred habitat in upstream zones was lithophils while in lower stretches it was lithopleagophils. On applying predictions of the River Continuum Concept, our results indicated the presence of a zonation pattern based on fish species assemblage and their ecological attributes along the longitudinal stretch of the Teesta River in west Bengal. Along the longitudinal stretch of the river, species richness increased downstream, with maximum richness in the mid-reaches. However, species richness decreased further downstream. The number of ecological guilds also increased downstream, and there were clear shifts in the structure of the guilds.

  18. Hydrological Mechanism for Arsenic Deposits in Meghna River Hyporheic Zone Sediments

    Science.gov (United States)

    Knappett, Peter; Datta, Saugata; Dimova, Natasha; Myers, Kimberly; Hossain, Abrar; Berube, Michelle; Shuai, Pin; Rhodes, Kimberly; Jewell, Katrina; Lipsi, Mehtaz; Hossain, Saddam; Hosain, Alamgir; Peterson, Jacqeline; Ahmed, Kazi

    2016-04-01

    Heavy metal deposits along the interface between aquifers and rivers have been discovered in diverse settings around the world. This so-called "Iron Curtain" is thought to be caused by groundwater flow towards the riverbank. To our knowledge the hydrology of this process hasn't been studied along a tidally influenced, completely fresh river-aquifer system. The Meghna River within the Ganges-Brahmaputra-Meghna Delta (GBMD) experiences tidal fluctuations that propagate over 400 km upstream, from the Bay of Bengal to Sylhet City. River and aquifer water levels also fluctuate seasonally by as much as 4 m as the region receives most of its ~ 2 m of rainfall from June through September. We studied a 10 km reach of the Meghna River 200 km north of the coast where the eastern side of the river is strongly gaining for most of the year. In contrast, the river both gains and loses water to shallow aquifers on the western side. High solid-phase iron (Fe) and arsenic (As) concentrations were previously observed in Meghna riverbank sediments. To test the hypothesis that groundwater discharge is responsible for depositing Fe and As in the riverbank we mapped major and trace element distribution at ~ 100 m spacing on both the east and west side of the river using X-ray fluorescence. The distribution of solid-phase Fe and As were compared to hydraulic gradients, hydraulic conductivity, and ambient liquid-phase concentrations in the riverbank aquifer. Hydraulic gradients were measured with transects of monitoring wells at three locations, and the 30 m deep shallow aquifer was mapped 500 m north and south parallel and orthogonal to each river bank using Electrical Resistivity Tomography (ERT). Resistivity, borehole logging, and slug tests indicate the aquifer dimensions and properties are remarkably consistent at the 3 locations on both sides of the river. Groundwater discharge to the river obtained from Darcy's Law and two independent methods indicate the high As deposits can

  19. New insights on the subsidence of the Ganges-Brahmaputra Delta Plain by using 2D multichannel seismic data, gravity and flexural modeling, BanglaPIRE Project

    Science.gov (United States)

    Grall, C.; Pickering, J.; Steckler, M. S.; Spiess, V.; Seeber, L.; Paola, C.; Goodbred, S. L., Jr.; Palamenghi, L.; Schwenk, T.

    2015-12-01

    Deltas can subside very fast, yet many deltas remain emergent over geologic time. A large sediment input is often enough to compensate for subsidence and rising sea level to keep many deltas at sea level. This implies a balance between subsidence and sedimentation, both of which may, however, be controlled by independent factors such as sediment supply, tectonic loads and sea-level change. We here examine the subsidence of the Ganges-Brahmaputra Delta (GBD). Located in the NE boundary of the Indian-Eurasian collision zone, the GBD is surrounded by active uplifts (Indo-Burma Fold Belt and the Shillong Massif). The pattern of subsidence from these tectonic loads can strongly vary depending on both loads and lithospheric flexural rigidity, both of which can vary in space and time. Sediment cover changes both the lithostatic pressure and the thermal properties and thus the rigidity of the lithosphere. While sediments are deposited cold, they also insulate the lithosphere, acting as a thermal blanket to increase lower crustal temperatures. These effects are a function of sedimentation rates and may be more important where the lithosphere is thin. At the massive GBD the impact of sedimentation should be considered for properly constraining flexural subsidence. The flexural rigidity of the lithosphere is here modeled by using a yield-stress envelope based on a thermomechanic model that includes geothermal changes associated with sedimentation. Models are constrained by using two different data sets, multichannel seismic data correlated to borehole stratigraphy, and gravity data. This approach allows us to determine the Holocene regional distribution of subsidence from the Hinge Zone to the Bengal Fan and the mass-anomalies associated with the flexural loading. Different end-member scenarios are explored for reproducing the observed land tilting and gravity anomalies. For all scenarios considered, data can be reproduced only if we consider an extremely weak lithosphere and

  20. Modelling the increased frequency of extreme sea levels in the Ganges-Brahmaputra-Meghna delta due to sea level rise and other effects of climate change.

    Science.gov (United States)

    Kay, S; Caesar, J; Wolf, J; Bricheno, L; Nicholls, R J; Saiful Islam, A K M; Haque, A; Pardaens, A; Lowe, J A

    2015-07-01

    Coastal flooding due to storm surge and high tides is a serious risk for inhabitants of the Ganges-Brahmaputra-Meghna (GBM) delta, as much of the land is close to sea level. Climate change could lead to large areas of land being subject to increased flooding, salinization and ultimate abandonment in West Bengal, India, and Bangladesh. IPCC 5th assessment modelling of sea level rise and estimates of subsidence rates from the EU IMPACT2C project suggest that sea level in the GBM delta region may rise by 0.63 to 0.88 m by 2090, with some studies suggesting this could be up to 0.5 m higher if potential substantial melting of the West Antarctic ice sheet is included. These sea level rise scenarios lead to increased frequency of high water coastal events. Any effect of climate change on the frequency and severity of storms can also have an effect on extreme sea levels. A shelf-sea model of the Bay of Bengal has been used to investigate how the combined effect of sea level rise and changes in other environmental conditions under climate change may alter the frequency of extreme sea level events for the period 1971 to 2099. The model was forced using atmospheric and oceanic boundary conditions derived from climate model projections and the future scenario increase in sea level was applied at its ocean boundary. The model results show an increased likelihood of extreme sea level events through the 21st century, with the frequency of events increasing greatly in the second half of the century: water levels that occurred at decadal time intervals under present-day model conditions occurred in most years by the middle of the 21st century and 3-15 times per year by 2100. The heights of the most extreme events tend to increase more in the first half of the century than the second. The modelled scenarios provide a case study of how sea level rise and other effects of climate change may combine to produce a greatly increased threat to life and property in the GBM delta by the end

  1. Interannual variability of upper tropospheric and lower stratospheric (UTLS) region over Ganges-Brahmaputra-Meghna basin based on COSMIC GNSS RO data

    Science.gov (United States)

    Khandu; Awange, J.; Forootan, E.

    2015-09-01

    Poor reliability of radiosonde observational networks across South Asia imposes serious challenges in understanding climate variability and thermodynamic structure of the upper-tropospheric and lower-stratospheric (UTLS) region. The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) mission launched in April 2006 have overcome many observational limitations that are inherent in conventional atmospheric sounding instruments. This study investigated the interannual variability of the UTLS region over the Ganges-Brahmaputra-Meghna (GBM) basin based on COSMIC radio occultation (RO) data from August 2006 to December 2013. Detailed comparisons were also made with various different radiosonde types and Numerical Weather Prediction (NWP) products. The results indicated that Indian Meteorological Department (IMD) radiosondes performed poorly despite upgrading to newer techniques. ShangE (of China) sonde showed the best agreement with COSMIC RO data with a mean temperature difference of -0.06 °C and a standard deviation of 1.44 °C while the older version (ShangM) indicated a cold bias of 0.61 °C in the UTLS region. The inter-annual variability of temperature in the UTLS region based on COSMIC RO data indicated a clear pattern of El Niño Southern Oscillation (ENSO) and Indian Ocean Dipole (IOD) while the stratospheric temperature anomalies reflected all three major Sudden Stratospheric Warming (SSW) events since 2007. The mean tropopause temperature varied from -70 to -80 °C, with an average height of about 15.5 to 16.3 km from winter to summer, indicating a pronounced annual cycle. The annual amplitudes of tropopause were found to be in the order of 0-6 °C and 0-1.5 km from tropical south to subtropical north. The anomalies of tropopause temperature and height exhibited the patterns of ENSO and IOD exceptionally well with a correlation of 0.65 and -0.52, respectively. The temperature data from Modern-Era Retrospective Analysis for Research

  2. Patterns of Downstream Fining and Facies Change Reflecting Differing Modes of Mid-Holocene Sediment Dispersal across the Ganges-Brahmaputra-Meghna Delta

    Science.gov (United States)

    Sincavage, R.; Goodbred, S. L., Jr.; Paola, C.

    2016-12-01

    The removal of sediment mass to deposition in sedimentary systems creates predictable patterns of downstream fining and facies changes. We examine the mid-Holocene sedimentary record of the Ganges-Brahmaputra-Meghna Delta (GBMD) in a mass balance framework to demonstrate a shift from bypass-dominated to extraction enhanced modes of sediment dispersal. A prolonged ( 3000 year) occupation of the tectonically-influenced Sylhet Basin occurred from 7.5-4.5 ka, producing thick (20-30 m) packages of channel sands and splay deposits. Sediment was initially ( 7.5-6.0 ka) routed along the western edge of Sylhet Basin, where confinement in antecedent valleys promoted bypass to downstream depocenters. This bypass dominance is reflected in low rates of downstream fining, minimal variability in percent sand values, and persistent channel sand preservation. At 6.0-5.5 ka, the system shifted to an extraction enhanced mode of sediment dispersal, as a large (3500 km2) splay developed northeast of the main sediment delivery pathway. Evidence for this shift includes rapid downstream fining and the prevalence of lower net:gross values in facies preserved in the deepest parts of the central basin. This pattern of deposition persists through the end of the occupation ( 4.5 ka) as reflected in another large ( 4000 km2) splay along the Shillong Foredeep at the basin's northern margin. The spatial distribution of sediment mass contained in each of the three pathways was apportioned spatially to calculate chi, a scale-independent dimensionless downstream distance that represents the total percent of supplied sediment flux lost to deposition at any given point in the system. Both of the splay deposits contain distinct facies shifts and a reduction in net:gross at a chi value of 0.6. The bypass-dominated pathway does not contain a full depositional length, meaning that true chi values cannot be calculated. However, a similar facies change and decrease in percent sand occurs at a geographic

  3. Enhancing University Courses and Field Schools through Cross-cultural Exchange: Joint US-Bangladeshi Trips to the Ganges-Brahmaputra and Mississippi Deltas

    Science.gov (United States)

    Steckler, M. S.; Goodbred, S. L., Jr.; Lowes, S.; Gilligan, J. M.; Ackerly, B.; Ahmed, K. M.; Akhter, S. H.; Sousa, D.; Wilson, C.; Datta, D. K.; Roy, K.; Mondal, D. R.

    2014-12-01

    As part of an NSF PIRE grant, we have led four field trips for undergraduate, MS and PhD students to large deltaic systems. Three trips took US students to the Ganges-Brahmaputra (GB) delta in Bangladesh and one brought Bangladeshi faculty and students to the Mississippi (Miss.) delta in the US. An essential component in the learning process and overall experience of each trip was that ~2/5 of the participants were students and professors from Bangladesh. In all cases, the involvement of a substantial international cohort greatly broadened perspectives on the topics being covered. For example, in GBD the local geologic and cultural knowledge of the Bangladeshis deepened the learning and engagement of the US students, an outcome that was almost universally noted in student reviews. The trips received similar feedback from Bangladeshi participants, as they had an enthusiastic and engaged audience of peers from the US. Even for the Miss. delta trip, the Bangladeshis added a unique perspective from a nation that faces similar environmental issues. These overwhelmingly positive contributions have been experienced in several different contexts. Three trips were associated with US courses and run over Spring Break. One matched sustainable development undergrads at Columbia U. with geology undergrads from Dhaka U., and two others matched a mixed group of graduate and undergrad students from Vanderbilt U. with cohorts from Bangladesh. The fourth trip was a stand-alone Field School for PhD students from 14 US universities and mostly MS students from 4 Bangladeshi universities. The focus of each trip ranged from broader surveys of tectonic, fluvial and coastal processes to investigations of geology and people affected by tropical storms. Of particular interest was the success of mixing undergrad and graduate students in the Vanderbilt course, which centered on the intersection of social sciences, physical sciences, and engineering. In this case, undergrads engaged in a

  4. Developing Rivers

    Directory of Open Access Journals (Sweden)

    Abhik Chakraborty

    2013-10-01

    Full Text Available This article explores the reasons behind the continuation of contentious dam projects in Japanese river basins. Though the River Law of the country was reformed in 1997, and subsequent sociopolitical developments raised hopes that river governance would progress toward a more environment-oriented and bottom-up model, basin governance in Japan remains primarily based on a utilitarian vision that sees rivers as waterways. This article reviews the Achilles heel of the 1997 River Law by examining some most contentious river valley projects, and concludes that a myth of vulnerability to flooding, short-sightedness of river engineers, and bureaucratic inertia combine to place basin governance in a time warp: as projects planned during postwar reconstruction and economic growth continue to be top priorities in policymaking circles while concerns over environment remain largely unaddressed.

  5. Isotope provenance of Eastern Himalayan rivers draining to the south into India, Nepal and Bhutan.

    Science.gov (United States)

    Gemignani, Lorenzo; Wijbrans, Jan; Najman, Yani; van der Beek, Peter

    2015-04-01

    The two syntaxis of the Himalaya (Eastern and western) are exhuming anomalously fast compared to the rest of Himalaya , and various hypothesis and models have been proposed to explain this, including coupled tectonic-erosion model of (Tectonic Aneurism)1-2 and ductile extrusion of weak lower crust from beneath Tibet by 'channel flow' 3 . The Namche Barwa metamorphic massif constitutes the eastern syntaxis of the belt and has experienced a complex history of uplift and deformation both influenced by intense fluvial erosion associated with the Yarlung-Tzangpo. Therefore, the Himalayas represent a unique natural laboratory where the interactions between the tectonics, erosion, climate and drainage evolution can be investigated. The purpose of the work is to understand in collaboration with other PhD students and European researchers collaborating in the iTECC Marie Curie Initial training Network the importance of processes involving the complex links and feedbacks between climate, tectonics and erosion. In this multi-disciplinary and multi-technique study the mains goals will be to assess the timing of rapid exhumation, to determine provenance source area exhumation of the syntaxis in relation to the big river capture event that has implicates the Yarlung-Tsangpo by the Brahmaputra, and the effect of the dilution of the syntaxis signal 's downstream. During the work the 40Ar/39Ar dating of single-grain detrital micas technique will be used to analyze smaller and younger grains using newly developed high sensitivity multi-collection noble gas mass spectrometry. Detrital zircon fission-track is perform to provides robust cooling age time of the sources terrains. Input from eastern syntaxis has been identified in the Brahmaputra sedimentary record by the appearance of very young grains (from 10 Ma to 6 Ma)4. To compare and to increase the previously collected data, fifteen samples from the Yarlung-Brahmaputra River system and from tributaries draining the Himalaya, the

  6. Global Overview On Delivery Of Sediment To The Coast From Tropical River Basins

    Science.gov (United States)

    Syvitski, J. P.; Kettner, A. J.; Brakenridge, G. R.

    2011-12-01

    Depending on definition, the tropics occupy between 16% and 19% of the earth's land surface, and discharge ~18.5% of the earth's fluvial water runoff. These flow regimes are driven by three types of sub-regional climate: rainforest, monsoon, and savannah. Even though the tropics include extreme precipitation events, particularly for the SE Asian islands, the general rainfall pattern alternates between wet and dry seasons as the ITCZ follows the sun and where annual monsoonal rain occurs. ITCZ convective rainfall is the dominant style of precipitation but this can be influenced by rare intra-tropical cyclone events, and by atmospheric river events set up by strong monsoonal conditions. Though a rainy season is normal (for example, portions of India discharge in summer may reach 50 times that of winter), the actual rainfall events are in the form of short bursts of precipitation (hours to days) separated by periods of dry (hours to weeks). Some areas of the tropics receive more than 100 thunderstorms per year. Rivers respond to this punctuated weather by seasonal flooding. For the smaller island nations and locales (e.g. Indonesia, Philippines, Borneo, Hainan, PNG, Madagascar, Hawaii, Taiwan) flash floods are common. Larger tropical river systems (Niger, Ganges, Brahmaputra, Congo, Amazon, Orinoco, Magdalena) show typical seasonally modulated discharges. The sediment flux from tropical rivers is approximately 17% to 19% of the global total - however individual river basins offer a wide range in sediment yields reflecting highly variable differences in their hinterland lithology, tectonic activity and volcanism, land-sliding, and relief. Human influences also greatly influence the range for tropical river sediment yield. Some SE Asian Rivers continue to be greatly affected by deforestation, road construction, and monoculture plantations. Sediment flux is more than twice the pre-Anthropocene flux in many of these SE Asian countries, especially where dams and reservoir

  7. Chronological trends in maximum and minimum water flows of the Teesta River, Bangladesh, and its implications

    Directory of Open Access Journals (Sweden)

    Md. Sanaul H. Mondal

    2017-01-01

    Full Text Available Bangladesh shares a common border with India in the west, north and east and with Myanmar in the southeast. These borders cut across 57 rivers that discharge through Bangladesh into the Bay of Bengal in the south. The upstream courses of these rivers traverse India, China, Nepal and Bhutan. Transboundary flows are the important sources of water resources in Bangladesh. Among the 57 transboundary rivers, the Teesta is the fourth major river in Bangladesh after the Ganges, the Brahmaputra and the Meghna and Bangladesh occupies about 2071 km2 . The Teesta River floodplain in Bangladesh accounts for 14% of the total cropped area and 9.15 million people of the country. The objective of this study was to investigate trends in both maximum and minimum water flow at Kaunia and Dalia stations for the Teesta River and the coping strategies developed by the communities to adjust with uncertain flood situations. The flow characteristics of the Teesta were analysed by calculating monthly maximum and minimum water levels and discharges from 1985 to 2006. Discharge of the Teesta over the last 22 years has been decreasing. Extreme low-flow conditions were likely to occur more frequently after the implementation of the Gozoldoba Barrage by India. However, a very sharp decrease in peak flows was also observed albeit unexpected high discharge in 1988, 1989, 1991, 1997, 1999 and 2004 with some in between April and October. Onrush of water causes frequent flash floods, whereas decreasing flow leaves the areas dependent on the Teesta vulnerable to droughts. Both these extreme situations had a negative impact on the lives and livelihoods of people dependent on the Teesta. Over the years, people have developed several risk mitigation strategies to adjust with both natural and anthropogenic flood situations. This article proposed the concept of ‘MAXIN (maximum and minimum flows’ for river water justice for riparian land.

  8. River nomads

    DEFF Research Database (Denmark)

    2016-01-01

    River nomads is a movie about people on the move. The documentary film explores the lifestyle of a group of nomadic fishermen whose mobility has been the recipe of success and troubles. Engaged in trade and travel, twice a year the river nomads form impressive convoys of majestic pirogues and set...... and liberated lifestyle and the breath-taking landscapes and vistas offered by the Niger River. River Nomads is also a personal account of the Kebbawa’s way of life and their current struggles as nomadic folk living in a world divided by borders and ruled by bureaucrats....

  9. River Piracy

    Indian Academy of Sciences (India)

    . Asiatic Soc. o/Bengal., 55:322-343.1886. C F Oldham. The Saraswati and the lost river of the Indian desertJ. R. Asiatic. Soc., 34:49-76. 1893. S C Sharma. The description of rivers in the Rigveda, The Geographical. Observer, 10:79-85. 1974.

  10. Impacts on river systems under 2 °C warming: Bangladesh Case Study

    Directory of Open Access Journals (Sweden)

    A.M. Zaman

    2017-08-01

    Full Text Available Bangladesh is particularly vulnerable due to the combined impacts of sea level rise, rainfall and runoff variability, and changes in cyclone patterns. This paper presents the application of an integrated modelling framework used to investigate climate change impacts when global averaged surface temperature increases by 2 °C from pre-industrial level. The modelling framework consists of four model types: Regional climate model (RCM, Ganges-Brahmaputra-Meghna (GBM Basin model, Southwest Region Hydrodynamic and Salinity models. Bias corrected climate results (temperature, precipitation and evapotranspiration from SMHI-RCA and CNRM-ARPEGE RCMs for (Representative Concentration Pathway RCP 8.5 scenario were used. The uniqueness of this research study was that the same GCM (General Circulation Model/RCM results were used across the whole modelling chain. In Bagerhat District, it was found that river salinity can increase by about 0.5 to 2 PPT (parts per thousand. Also, the duration of river salinity above 1 PPT can double in some locations. In Kushtia District, in the months of November and December river flows may increase but not sufficiently in other months due to lack of connectivity to the Ganges River. In the flood-prone Shariatpur District, average wet season water level increases up to 0.2 to 0.5 m. Also, duration of flood levels above the established danger level can double in some locations. Finally, this study found that dredging of the mouth of the Gorai River (in Kushtia District is an effective adaptation measure. The dredging ensures connectivity to the Ganges River, which allows freshwater to enter the Southwest region of Bangladesh, which not only alleviates drought conditions in Kushtia Distract but also helps push back saline intrusion.

  11. Habitat fragmentation and species extirpation in freshwater ecosystems; causes of range decline of the Indus river dolphin (Platanista gangetica minor).

    Science.gov (United States)

    Braulik, Gill T; Arshad, Masood; Noureen, Uzma; Northridge, Simon P

    2014-01-01

    Habitat fragmentation of freshwater ecosystems is increasing rapidly, however the understanding of extinction debt and species decline in riverine habitat fragments lags behind that in other ecosystems. The mighty rivers that drain the Himalaya - the Ganges, Brahmaputra, Indus, Mekong and Yangtze - are amongst the world's most biodiverse freshwater ecosystems. Many hundreds of dams have been constructed, are under construction, or are planned on these rivers and large hydrological changes and losses of biodiversity have occurred and are expected to continue. This study examines the causes of range decline of the Indus dolphin, which inhabits one of the world's most modified rivers, to demonstrate how we may expect other vertebrate populations to respond as planned dams and water developments come into operation. The historical range of the Indus dolphin has been fragmented into 17 river sections by diversion dams; dolphin sighting and interview surveys show that river dolphins have been extirpated from ten river sections, they persist in 6, and are of unknown status in one section. Seven potential factors influencing the temporal and spatial pattern of decline were considered in three regression model sets. Low dry-season river discharge, due to water abstraction at irrigation barrages, was the principal factor that explained the dolphin's range decline, influencing 1) the spatial pattern of persistence, 2) the temporal pattern of subpopulation extirpation, and 3) the speed of extirpation after habitat fragmentation. Dolphins were more likely to persist in the core of the former range because water diversions are concentrated near the range periphery. Habitat fragmentation and degradation of the habitat were inextricably intertwined and in combination caused the catastrophic decline of the Indus dolphin.

  12. Habitat fragmentation and species extirpation in freshwater ecosystems; causes of range decline of the Indus river dolphin (Platanista gangetica minor.

    Directory of Open Access Journals (Sweden)

    Gill T Braulik

    Full Text Available Habitat fragmentation of freshwater ecosystems is increasing rapidly, however the understanding of extinction debt and species decline in riverine habitat fragments lags behind that in other ecosystems. The mighty rivers that drain the Himalaya - the Ganges, Brahmaputra, Indus, Mekong and Yangtze - are amongst the world's most biodiverse freshwater ecosystems. Many hundreds of dams have been constructed, are under construction, or are planned on these rivers and large hydrological changes and losses of biodiversity have occurred and are expected to continue. This study examines the causes of range decline of the Indus dolphin, which inhabits one of the world's most modified rivers, to demonstrate how we may expect other vertebrate populations to respond as planned dams and water developments come into operation. The historical range of the Indus dolphin has been fragmented into 17 river sections by diversion dams; dolphin sighting and interview surveys show that river dolphins have been extirpated from ten river sections, they persist in 6, and are of unknown status in one section. Seven potential factors influencing the temporal and spatial pattern of decline were considered in three regression model sets. Low dry-season river discharge, due to water abstraction at irrigation barrages, was the principal factor that explained the dolphin's range decline, influencing 1 the spatial pattern of persistence, 2 the temporal pattern of subpopulation extirpation, and 3 the speed of extirpation after habitat fragmentation. Dolphins were more likely to persist in the core of the former range because water diversions are concentrated near the range periphery. Habitat fragmentation and degradation of the habitat were inextricably intertwined and in combination caused the catastrophic decline of the Indus dolphin.

  13. A data assimilation system combining CryoSat-2 data and hydrodynamic river models

    Science.gov (United States)

    Schneider, Raphael; Ridler, Marc-Etienne; Godiksen, Peter Nygaard; Madsen, Henrik; Bauer-Gottwein, Peter

    2018-02-01

    There are numerous hydrologic studies using satellite altimetry data from repeat-orbit missions such as Envisat or Jason over rivers. This study is one of the first examples for the combination of altimetry from drifting-ground track satellite missions, namely CryoSat-2, with a river model. CryoSat-2 SARIn Level 2 data is used to improve a 1D hydrodynamic model of the Brahmaputra River in South Asia, which is based on the Saint-Venant equations for unsteady flow and set up in the MIKE HYDRO River software. After calibration of discharge and water level the hydrodynamic model can accurately and bias-free represent the spatio-temporal variations of water levels. A data assimilation framework has been developed and linked with the model. It is a flexible framework that can assimilate water level data which are arbitrarily distributed in time and space. The setup has been used to assimilate CryoSat-2 water level observations over the Assam valley for the years 2010-2015, using an Ensemble Transform Kalman Filter (ETKF). Performance improvement in terms of discharge forecasting skill was then evaluated. For experiments with synthetic CryoSat-2 data the continuous ranked probability score (CRPS) was improved by up to 32%, whilst for experiments assimilating real data it could be improved by up to 10%. The developed methods are expected to be transferable to other rivers and altimeter missions. The model setup and calibration is based almost entirely on globally available remote sensing data.

  14. A Consistent Radar Altimetry Dataset for Major World Rivers: Extraction Methods and Preliminary Data Products

    Science.gov (United States)

    Coss, S. P.; Durand, M. T.; Tuozzolo, S.; Yi, Y.; Jia, Y.; Guo, Q.; Shum, C. K.

    2015-12-01

    Our group has made several efforts to develop the systematics for processing multiple satellite mission inland altimetry data with the purpose of creating a pre-SWOT climate data record of world's rivers greater than 900m in width. The project is a component of a NASA MEaSUREs (Making Earth System Data Records for Use in Research Environments) project undertaken by UCLA, Princeton U., NASA/GSFC and Ohio State Univ. The first method developed allows for the identification of measurements that represent the target river through height filtering and is based on USGS flow data from 105 gauges on rivers with watersheds over 20,000 km2. Proximal topographic variations led to some contamination of the radar returns. We were able to identify them using the previously mentioned height filter, and correlated their frequency with near-river topographic indices. Significant efforts have also been made to detect river ice using only radar backscatter. Over 631 Landsat images were processed and given an ice cover designation then compared with measured backscatter profiles; demonstrating that isolating a one- to-one relationship between ice and backscatter will be challenging. An additional focus of the group has been automation of detecting altimeter/river intersections as well as the creation of "virtual stations" or masks for data extraction at those locations. Using RivWidth parameters to generate polygons and a raster proximity based intersection detection methods have both shown promising results for automation of this process. This project will soon be producing validated climate data records in the form of geocentric river height changes, both in terms of scale of the study area and access to previously unmonitored regions. Once established, these methods will also be applicable to the study of future satellite cycles. Preliminary river height change data products have been produced for the Mississippi, St Lawrence, Yukon, Mackenzie, and part of the Ganges-Brahmaputra

  15. Antecedent morphology and active tectonics in the upper Bengal Delta: Multi-temporal controls on river mobility and sediment preservation

    Science.gov (United States)

    Pickering, J.; Goodbred, S. L.; Hartzog, T.; Spiess, V.; Schwenk, T.; Palamenghi, L.; Steckler, M. S.; Seeber, L.; Akhter, S. H.; Mondal, D.; Hossain, S.; Petter, A. L.; Paola, C.

    2012-12-01

    The upper Bengal delta is a tectonically active depositional environment composed of unconsolidated muds and sands constructed by channel migration, avulsion, and overbank processes. These riverine sediments define the channels, floodplains, and terraces that make up the surface morphology of the upper delta plain. Until recently, the stratigraphic architecture underlying this surface morphology was poorly defined, and at present, both the origin of the upland terraces and the nature of the river avulsions continue to be debated. However, stratigraphic results from a 41-well drilling transect and a corresponding high-resolution multichannel seismic expedition in 2011 in north-central Bangladesh have begun to reveal the subsurface distribution of sediments in this dynamic environment. Two adjacent sand-dominated Holocene channel systems, presently occupied by the Jamuna and Old Brahmaputra Rivers, are each bounded by mud-capped morphological features. Pleistocene-aged terraces (Barind and Madhupur Terraces) bound the modern Jamuna River valley on either side. These terraces are composed of fining-upward fluviodeltaic deposits capped by 5-10 m of mud. The Madhupur Terrace also forms the southwestern boundary of the alternate channel course along the Old Brahmaputra, and the northeastern boundary of this valley is formed by a tectonically influenced wedge of Pleistocene mud (Sylhet Basin). This wedge is capped by a thin veneer of Holocene mud interfingered with ephemeral channel sands derived from the overthrusting 2-km high Shillong Anticline. Each of these mud-capped morphological deposits represents an area of the delta that has persisted throughout the Pleistocene; thus we focus on these fine-grained sediments in an effort to understand the long-term transition from surface morphology to preserved stratigraphy. We suggest that these Pleistocene features are an important control on river course mobility, and subsequently, on sediment deposition and preservation, at

  16. Contested Rivers

    DEFF Research Database (Denmark)

    Gorm Hansen, Louise Lyngfeldt

    explores translocal connections through ethnographic fieldwork at a global water conference and preliminary fieldwork at chosen locations on China's Nu River. The Nu River is one of the last undammed rivers in Asia and runs through China close to the Chinese-Burmese border, then flows into the Andaman Sea...... policy making, decision drivers and framing of large hydropower projects in China. Hydropower is a complex and interesting field to explore as the consequences go beyond the immediate locality and interacts with local as well as the global contexts. Inspired by Tsing (2003) and Zhan (2008) the paper...... and natural scientists and Chinese hydropower companies (to name a few). The paper maps different actors’ framing of the issue to gain a deeper understanding of the complexities of hydropower policymaking in China, as well as map the local consequences of global policymaking about large hydropower...

  17. Compound simulation of fluvial floods and storm surges in a global coupled river-coast flood model: Model development and its application to 2007 Cyclone Sidr in Bangladesh

    Science.gov (United States)

    Ikeuchi, Hiroaki; Hirabayashi, Yukiko; Yamazaki, Dai; Muis, Sanne; Ward, Philip J.; Winsemius, Hessel C.; Verlaan, Martin; Kanae, Shinjiro

    2017-08-01

    Water-related disasters, such as fluvial floods and cyclonic storm surges, are a major concern in the world's mega-delta regions. Furthermore, the simultaneous occurrence of extreme discharges from rivers and storm surges could exacerbate flood risk, compared to when they occur separately. Hence, it is of great importance to assess the compound risks of fluvial and coastal floods at a large scale, including mega-deltas. However, most studies on compound fluvial and coastal flooding have been limited to relatively small scales, and global-scale or large-scale studies have not yet addressed both of them. The objectives of this study are twofold: to develop a global coupled river-coast flood model; and to conduct a simulation of compound fluvial flooding and storm surges in Asian mega-delta regions. A state-of-the-art global river routing model was modified to represent the influence of dynamic sea surface levels on river discharges and water levels. We conducted the experiments by coupling a river model with a global tide and surge reanalysis data set. Results show that water levels in deltas and estuaries are greatly affected by the interaction between river discharge, ocean tides and storm surges. The effects of storm surges on fluvial flooding are further examined from a regional perspective, focusing on the case of Cyclone Sidr in the Ganges-Brahmaputra-Meghna Delta in 2007. Modeled results demonstrate that a >3 m storm surge propagated more than 200 km inland along rivers. We show that the performance of global river routing models can be improved by including sea level dynamics.

  18. The contribution of sea-level rise to flooding in large river catchments

    Science.gov (United States)

    Thiele-Eich, I.; Hopson, T. M.; Gilleland, E.; Lamarque, J.; Hu, A.; Simmer, C.

    2012-12-01

    Climate change is expected to both impact sea level rise as well as flooding. Our study focuses on the combined effect of climate change on upper catchment precipitation as well as on sea-level rise at the river mouths and the impact this will have on river flooding both at the coast and further upstream. We concentrate on the eight catchments of the Amazonas, Congo, Orinoco, Ganges/Brahmaputra/Meghna, Mississippi, St. Lawrence, Danube and Niger rivers. To assess the impact of climate change, upper catchment precipitation as well as monthly mean thermosteric sea-level rise at the river mouth outflow are taken from the four CCSM4 1° 20th Century ensemble members as well as from six CCSM4 1° ensemble members for the RCP scenarios RCP8.5, 6.0, 4.5 and 2.6. Continuous daily time series for average catchment precipitation and discharge are available for each of the catchments. To arrive at a future discharge time series, we used these observations to develop a simple statistical hydrological model which can be applied to the modelled future upper catchment precipitation values. The analysis of this surrogate discharge time series alone already yields significant changes in flood return levels as well as flood duration. Using the geometry of the river channel, the backwater effect of sea-level rise is incorporated in our analysis of both flood frequencies and magnitudes by calculating the effective additional discharge due to the increase in water level at the river mouth outflow, as well as its tapering impact upstream. By combining these effects, our results focus on the merged impact of changes in extreme precipitation with increases in river height due to sea-level rise at the river mouths. Judging from our preliminary results, the increase in effective discharge due to sea-level rise cannot be neglected when discussing late 21st century flooding in the respective river basins. In particular, we find that especially in countries with low elevation gradient, flood

  19. Time-scales of erosion and weathering processes in the Himalayan river system: Element and isotope approach using the U-series; Constantes de temps des processus d'erosion et d'alteration dans le systeme himalayen: approche geochimique elementaire et isotopique par les series de l'uranium

    Energy Technology Data Exchange (ETDEWEB)

    Granet, M

    2007-06-15

    The time-scales of erosion and weathering processes are key parameters which need to be determined to understand the response of the reliefs to external forcing like tectonics, climate and human activities. They were recovered by using U-series nuclides analyzed in sediments and suspended materials carried by the Himalayan rivers of the Ganges and Brahmaputra basins. In the Ganges basin, the time-scales of weathering determined from the study of coarse sediments carried by the Kali Gandaki range from several ky, where the uplift is located, to 350 ky. Such values indicate that the bed-rocks are in situ weathered for a long period before the weathering residual products get transported in the rivers as coarse sediments. At the outlet of the high range, these sediments are carried by the tributaries of the Ganges, the Gandak and Ghaghara, during a transfer period of about 100 ka. The study of the sediments at the outlet of the Brahmaputra tributaries allows to propose time-scales of weathering ranging from 110 to 270 ky. Such long periods confirm that during their transfer in the plains, the sediments are temporarily trapped at several places in the basins. In the Ganges and Brahmaputra rivers, the time-scales of sedimentary transfer are 575 and 160 ky, respectively. These values, which are of the same order as their response times, are much longer than the timescales of the Quaternary climate oscillations. It confirms the buffering action of the asiatic alluvial plains for the high-frequency sediment flux variations in response to external forcing in the chain. The study of suspended materials suggests that their chemical compositions result from the mixing of coarse river sediments with fine particles from various locations in the basin which are affected by vegetation recycling. By contrast to coarse sediments, the time-scales of transfer for the suspended materials are fast, e.g. a few ky, pointing the potential of U-series nuclides to assess particle transport

  20. River Piracy

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 1; Issue 5. River Piracy Saraswati that Disappeared. K S Valdiya. General Article Volume 1 Issue 5 May 1996 pp 19-28. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/001/05/0019-0028. Author Affiliations.

  1. Assessing modern rates of river sediment discharge to the ocean using satellite gravimetry

    Science.gov (United States)

    Mouyen, Maxime; Longuevergne, Laurent; Steer, Philippe; Crave, Alain; Lemoine, Jean-Michel; Save, Himanshu; Robin, Cécile

    2017-04-01

    Worldwide rivers annually export about 19 Gigatons of sediments to the ocean that mostly accumulate in the coastal zones and on the continental shelves. This sediment discharge testifies of the intensity of continental erosion and records changes in climate, tectonics and human activity. However, natural and instrumental uncertainties inherent to the in-situ measurements of sediment discharge prevent from conclusive estimates to better understand these linkages. Here we develop a new method, using the Gravity Recovery and Climate Experiment (GRACE) satellite data, to infer mass-integrative estimates of sediment discharge of large rivers to the ocean. GRACE satellite provides global gravity time series that have proven useful for quantifying mass transport, including continental water redistribution at the Earth surface (ice sheets and glaciers melting, groundwater storage variations) but has been seldom used for monitoring sediment mass transfers so far. Here we pair the analysis of regularized GRACE solutions at high spatial resolution corrected from all known contributions (hydrology, ocean, atmosphere) to a particle tracking model that predicts the location of the sediment sinks for 13 rivers with the highest sediments loads in the world. We find that the resulting GRACE-derived sediment discharges off the mouth of the Amazon, Ganges-Brahmaputra, Changjiang (Yangtze), Indus, Magdalena, Godavari and Mekong rivers are consistent with in-situ measurements. Our results suggest that the lack of time continuity and of global coverage in terrestrial sediment discharge measurements could be reduced by using GRACE, which provides global and continuous data since 2002. GRACE solutions are regularly improved and new satellite gravity missions are being prepared hence making our approach even more relevant in a near future. The accumulation of sediments over time will keep increasing the signal to noise ratio of the gravity time series, which will improve the precision of

  2. Antecedent Rivers

    Indian Academy of Sciences (India)

    far north of the high NandaDevi (7,817 m) - Api Nampa. (7,132 m) range of the Himadri. The Sindhu flows northwestwards, the Satluj goes west, the Karnali takes the southerly course and the Tsangpo flows east. These rivers flow through their pristine channels, carved out at the very outset about 50 to 55 m.y (million years) ...

  3. Effectiveness of water infrastructure for river flood management – Part 1: Flood hazard assessment using hydrological models in Bangladesh

    Directory of Open Access Journals (Sweden)

    M. A. Gusyev

    2015-06-01

    Full Text Available This study introduces a flood hazard assessment part of the global flood risk assessment (Part 2 conducted with a distributed hydrological Block-wise TOP (BTOP model and a GIS-based Flood Inundation Depth (FID model. In this study, the 20 km grid BTOP model was developed with globally available data on and applied for the Ganges, Brahmaputra and Meghna (GBM river basin. The BTOP model was calibrated with observed river discharges in Bangladesh and was applied for climate change impact assessment to produce flood discharges at each BTOP cell under present and future climates. For Bangladesh, the cumulative flood inundation maps were produced using the FID model with the BTOP simulated flood discharges and allowed us to consider levee effectiveness for reduction of flood inundation. For the climate change impacts, the flood hazard increased both in flood discharge and inundation area for the 50- and 100-year floods. From these preliminary results, the proposed methodology can partly overcome the limitation of the data unavailability and produces flood~maps that can be used for the nationwide flood risk assessment, which is presented in Part 2 of this study.

  4. River Corridor Easements

    Data.gov (United States)

    Vermont Center for Geographic Information — A River Corridor Easement (RCE) is an area of conserved land adjacent to a river or stream that was conserved to permanently protect the lateral area the river needs...

  5. Ganga-Brahmaputra river discharge from Jason-2 radar altimetry: An update to the long-term satellite-derived estimates of continental freshwater forcing flux into the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Papa, F.; Bala, S.K.; Pandey, R.K.; Durand, F.; Gopalakrishna, V.V.; Rahman, A.; Rossow, W.B.

    TOPEX-Poseidon, ERS-2 and ENVISAT, and is now extended using Jason-2. To take full advantages of the new availability of in situ rating curves, the processing scheme is adapted and the adjustments of the methodology are discussed here. First, using a...

  6. 33 CFR 162.90 - White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false White River, Arkansas Post Canal... White River, Arkansas Post Canal, Arkansas River, and Verdigris River between Mississippi River, Ark... apply to: (1) Waterways. White River between Mississippi River and Arkansas Post Canal, Ark.; Arkansas...

  7. Structure, provenance and residence time of terrestrial organic carbon: insights from Programmed temperature Pyrolysis-Combustion of river sediments

    Science.gov (United States)

    Feng, X.; Galy, V.; Rosenheim, B. E.; Roe, K. M.; Williams, E. K.

    2010-12-01

    be itself composed of several components characterized by different reactivity and radiocarbon content. In sediments from the Ganges-Brahmaputra river system we identified at least two main constituents of the biospheric OC pool: 1) a labile component whose radiocarbon content agrees with that of vascular plant biomarkers and, 2) a refractory component, characterized by a very long residence time (ca. 17 Ka). Our first results indicate that PTP-CS has very promising potential to quantify the contribution and residence time of the different components of riverine OC. We expect it will permit significant advance in our understanding of the rate of exchange and flux of terrestrial OC during continental erosion.

  8. River pollution control

    National Research Council Canada - National Science Library

    Stiff, M.J

    1980-01-01

    Readers will gain an insight into the problems of other countries, particularly those with trans-frontier rivers, the measures adopted to improve river quality, and how the World Health Organization...

  9. Allegheny County Major Rivers

    Data.gov (United States)

    Allegheny County / City of Pittsburgh / Western PA Regional Data Center — This dataset contains locations of major rivers that flow through Allegheny County. These shapes have been taken from the Hydrology dataset. The Ohio River,...

  10. Illinois River NWFR HMP

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Illinois River National Wildlife and Fish Refuges Complex stretches along 124 miles of the Illinois River in west central Illinois. The Complex includes three...

  11. Iowa's Sovereign Meandered Rivers

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This data set depicts Iowa's Meandered Rivers. These rivers are deemed sovereign land & therefore require any person wishing to conduct construction activities...

  12. Distribution of rare earth elements and heavy metals in the surficial sediments of the Himalayan river system

    National Research Council Canada - National Science Library

    Ramesh, R; Ramanathan, Al; Ramesh, S; Purvaja, R; Subramanian, V

    2000-01-01

    .... REEs and heavy metals (V, Pb, Cr, Co, Ag, Zn, Cd, Ni) were analyzed from the suspended sediments of Ganges and surficial sediments of Yamuna, Brahmaputra, Jamuna, Padma and Meghna, using VG Thermal Ionization Mass Spectrometer...

  13. Measuring River Pollution

    Science.gov (United States)

    Ayyavoo, Gabriel

    2004-01-01

    The Don River watershed is located within Canada's most highly urbanized area--metropolitan Toronto. Many residential and commercial uses, including alterations to the river's course with bridges, have had a significant impact on the Don's fauna and flora. Pollutants have degraded the river's water quality, a situation exacerbated by the…

  14. River basin administration

    Science.gov (United States)

    Management of international rivers and their basins is the focus of the Centre for Comparative Studies on (International) River Basin Administration, recently established at Delft University of Technology in the Netherlands. Water pollution, sludge, and conflicting interests in the use of water in upstream and downstream parts of a river basin will be addressed by studying groundwater and consumption of water in the whole catchment area of a river.Important aspects of river management are administrative and policy aspects. The Centre will focus on policy, law, planning, and organization, including transboundary cooperation, posing standards, integrated environmental planning on regional scale and environmental impact assessments.

  15. Rivers: Nature's Wondrous Waterways.

    Science.gov (United States)

    Harrison, David L.

    Rivers play a vital role in the life of the planet. They provide water for wildlife, plant life, and people, and they help to fertilize fields where corn and other crops grow. But how were these rivers made? This children's book takes readers/students on a journey down a river from its source at the top of a mountain to its mouth where it meets…

  16. Evolution of river dolphins.

    OpenAIRE

    Hamilton, H.; Caballero, S.; Collins, A. G.; Brownell, R. L.

    2001-01-01

    The world's river dolphins (Inia, Pontoporia, Lipotes and Platanista) are among the least known and most endangered of all cetaceans. The four extant genera inhabit geographically disjunct river systems and exhibit highly modified morphologies, leading many cetologists to regard river dolphins as an unnatural group. Numerous arrangements have been proposed for their phylogenetic relationships to one another and to other odontocete cetaceans. These alternative views strongly affect the biogeog...

  17. Down to the River

    DEFF Research Database (Denmark)

    Wessels, Josepha Ivanka

    2015-01-01

    Currently there is no coherent or sustainable water cooperation among the five states—Israel, Jordan, Lebanon, Palestinian territories and Syria—that share the Jordan River. Why do people not cooperate on sustainable river basin management, even if it seems the most rational course from...... to illustrate hydropolitics in praxis, because the political future of this particular area in many respects affects the sustainable future of the Jordan River Basin and the entire Levant....

  18. Origins, seasonality, and fluxes of organic matter in the Congo River

    Science.gov (United States)

    Spencer, Robert G. M.; Hernes, Peter J.; Dinga, Bienvenu; Wabakanghanzi, Jose N.; Drake, Travis W.; Six, Johan

    2016-07-01

    The Congo River in central Africa represents a major source of organic matter (OM) to the Atlantic Ocean. This study examined elemental (%OC, %N, and C:N), stable isotopic (δ13C and δ15N), and biomarker composition (lignin phenols) of particulate OM (POM) and dissolved OM (DOM) across the seasonal hydrograph. Even though the Congo exhibits an extremely stable intra-annual discharge regime, seasonal variability in OM composition was evident. DOM appears predominantly derived from vascular plant inputs with greater relative contribution during the rising limb and peak in discharge associated with the major November-December discharge maximum. Generally, POM appears to be sourced from soil-derived mineral-associated OM (low C:N, low Λ8, and higher (Ad:Al)v) but the relative proportion of fresh vascular plant material (higher C:N, higher Λ8, and lower (Ad:Al)v) increases with higher discharge. During the study period (September 2009 to November 2010) the Congo exported 29.21 Tg yr-1 of total suspended sediment (TSS), 1.96 Tg yr-1 of particulate organic carbon (POC), and 12.48 Tg yr-1 of dissolved organic carbon. The Congo exports an order of magnitude lower TSS load in comparison to other major riverine sources of TSS (e.g., Ganges and Brahmaputra), but due to its OM-rich character it actually exports a comparable amount of POC. The Congo is also 2.5 times more efficient at exporting dissolved lignin per unit volume compared to the Amazon. Including Congo dissolved lignin data in residence time calculations for lignin in the Atlantic Ocean results in an approximately 10% reduction from the existing estimate, suggesting that this material is more reactive than previously thought.

  19. Organic carbon removal in the sea: the continental connection

    Digital Repository Service at National Institute of Oceanography (India)

    Ittekkot, V.; Haake, B.; Bartsch, M.; Nair, R.R.; Ramaswamy, V.

    maxima coincide with the period of maximum discharge of the Ganges and Brahmaputra rivers during which river plumes enriched in nutrients are advected into offshore areas. Additionally, the winds and river plums supply enormous amounts of mineral matter...

  20. River Corridors (Jan 2, 2015)

    Data.gov (United States)

    Vermont Center for Geographic Information — River corridors are delineated to provide for the least erosive meandering and floodplain geometry toward which a river will evolve over time. River corridor maps...

  1. Improvement of the SPHY Model Glacier Module and its Application in the Tamakoshi River Basin, Nepal

    Science.gov (United States)

    Terink, W.; Lutz, A. F.; Immerzeel, W.; Nepal, S.; Khanal, S.; Shrestha, A. B.

    2016-12-01

    Snow and ice reserves are an important source of water for several regions around the globe, especially for the people living in the river basins in the Himalayan region. More than 1 billion people depend on the water resources from the Indus, Ganges, Brahmaputra, Yangtze, and Yellow Rivers. The upstream snow and ice reserves are exposed to the effects of climate change, making long-term water availability in this region more challenging. Increased temperatures result in reduced glacier and snow covered areas due to the increased melting of snow and ice as well as reduced accumulation of snow. To study these snow and glacier melting and accumulation processes, it is crucial to have model concepts available that describe these processes accurately without the need of data demanding energy-balance approaches. For this reason we have improved and validated the glacier module in the Spatial Processes in HYdrology (SPHY) v2.0 model. Within the current version of the SPHY model (v2.0), glaciers are not mass-conserving; i.e. precipitation falling onto the glacier surface as either rain or snow is not accounted for. The current version of SPHY schematizes glaciers as fixed entities melting with a rate depending on temperature and a degree-day-factor. A coarser model grid resolution is often required to be computation efficient in case of larger modeling areas. In this case substantial errors in the estimation of melt from snow and glaciers can be made because of the assumption of the same air temperature for the entire grid cell, which in reality differs for the various glaciers located at different altitudes within the grid cell. Within the improved glacier module for SPHY each model grid cell can contain one or more unique glaciers, being either debris covered or debris free. Each unique combination of model grid cell ID and glacier ID leads to an elevation difference, enabling accurate temperature estimates per glacier in each model grid cell. This makes it possible to

  2. How Much Do We Know about the Storage Changes in the Major River Basins of the World? Analysis of Storage Change from GRACE

    Science.gov (United States)

    Velpuri, N. M.; Senay, G. B.; Verdin, J. P.

    2014-12-01

    Change in storage is an important component of water cycle that is often ignored in large-scale hydrologic studies due to limited data and difficulty in measurement. For the first time, this study quantifies and inter-compares storage changes in major river basins of the world. Gravity Recovery and Climate Experiment (GRACE) monthly mass deviation in storage (MDS) data over 2003-2013 is used to compute monthly, annual and long-term change in storage (ΔS) for 51 major river basins of the world (> 200,000 km2). For each river basin, GRACE ΔS is analyzed to understand a) temporal variability in ΔS b) magnitude of ΔS at annual and decadal time scales and c) duration of storage cycle (time taken by a basin in months to return to initial storage condition). This study identified that 11, 33 and 7 out of 51 basins showed high, medium and low month to month variability in storage changes, respectively. Compared to basin precipitation, 48 out of 51 river basins showed storage to be considerable (5 - 35% of basin annual precipitation). Only 3 basins (Irrawaddy, St. Lawrence, and Brahmaputra) showed minimum variability in storage (river basins showed negligible storage changes (Zambezi, Mekong, Orinoco, Tocantins, and Amazon) showed annual storage cycle of 12 months. Our results indicate that most basins within the tropics show positive correlation with precipitation indicating that precipitation is the main driver of storage. On the other hand, ΔS in the basins located in the higher latitudes mostly show negative correlation with precipitation. This study provides new insights into how basin storage changes in the major river basins. Future study would focus on the analysis of ΔS over large river basins within the United States. Such analysis and estimates of ΔS would help to (i) improve our knowledge of water availability and (ii) meet the goals of the WaterSMART (Sustain and Manage America's Resources for Tomorrow) project.

  3. Modelling river dune development

    NARCIS (Netherlands)

    Paarlberg, Andries; Weerts, H.J.T.; Dohmen-Janssen, Catarine M.; Ritsema, I.L; Hulscher, Suzanne J.M.H.; van Os, A.G.; Termes, A.P.P.

    2005-01-01

    Since river dunes influence flow resistance, predictions of dune dimensions are required to make accurate water level predictions. A model approach to simulate developing river dunes is presented. The model is set-up to be appropriate, i.e. as simple as possible, but with sufficient accuracy for

  4. Evolution of river dolphins.

    Science.gov (United States)

    Hamilton, H; Caballero, S; Collins, A G; Brownell, R L

    2001-03-07

    The world's river dolphins (Inia, Pontoporia, Lipotes and Platanista) are among the least known and most endangered of all cetaceans. The four extant genera inhabit geographically disjunct river systems and exhibit highly modified morphologies, leading many cetologists to regard river dolphins as an unnatural group. Numerous arrangements have been proposed for their phylogenetic relationships to one another and to other odontocete cetaceans. These alternative views strongly affect the biogeographical and evolutionary implications raised by the important, although limited, fossil record of river dolphins. We present a hypothesis of river dolphin relationships based on phylogenetic analysis of three mitochondrial genes for 29 cetacean species, concluding that the four genera represent three separate, ancient branches in odontocete evolution. Our molecular phylogeny corresponds well with the first fossil appearances of the primary lineages of modern odontocetes. Integrating relevant events in Tertiary palaeoceanography, we develop a scenario for river dolphin evolution during the globally high sea levels of the Middle Miocene. We suggest that ancestors of the four extant river dolphin lineages colonized the shallow epicontintental seas that inundated the Amazon, Paraná, Yangtze and Indo-Gangetic river basins, subsequently remaining in these extensive waterways during their transition to freshwater with the Late Neogene trend of sea-level lowering.

  5. Nipigon River landslide, 1990

    Energy Technology Data Exchange (ETDEWEB)

    Radhakrishna, H.S.; Lau, K.C.

    1992-11-24

    On April 23, 1990, a landslide occurred on the east bank of the Nipigon River in Ontario, 8 km downstream from the Alexander Generating Station. A study was initiated to assess the impact of river level fluctuations caused by the hydropower plant operation on the downstream banks of the river. A detailed geotechnical investigation and field study of river drawdown effects on the riverbank slopes were performed. A final analysis of the failure is presented which shows that the high groundwater conditions and soft soils present in the area led to the massive landslide. The impact of the river level fluctuations on the slope stability was found to be minor compared to that of the high groundwater conditions that were produced by the rapid thaw of snow and infiltration in the recharge area. 15 refs., 16 figs., 6 tabs.

  6. Numerical modelling of river processes: flow and river bed deformation

    NARCIS (Netherlands)

    Tassi, P.A.

    2007-01-01

    The morphology of alluvial river channels is a consequence of complex interaction among a number of constituent physical processes, such as flow, sediment transport and river bed deformation. This is, an alluvial river channel is formed from its own sediment. From time to time, alluvial river

  7. Mixing in a river

    Energy Technology Data Exchange (ETDEWEB)

    Bernath, L.; Menegus, R.L.; Ring, H.F.

    1956-05-09

    Many rivers are burdened with tributary streams of warm water and/or liquid wastes containing dissolved or suspended matter. The warm water and waste matter mix thoroughly with the river water some distance downstream from the point of entry of the tributary, but near the point of entry there may be high local temperatures or concentrations of waste. It is often necessary to know the local temperatures or concentrations of waste. The authors have used a formula for computing the turbulent mixing that takes place in such a situation; this formula fits quite well in the case of one Southern river.

  8. One-dimensional modeling of a recent Ganga avulsion: Assessing the potential effect of tectonic subsidence on a large river

    Science.gov (United States)

    Gupta, Niladri; Kleinhans, Maarten G.; Addink, Elisabeth A.; Atkinson, Peter M.; Carling, Paul A.

    2014-05-01

    by residual channel filling but in the much larger Ganges results in morphologically active anabranches. The model results reveal that neither a gradient advantage nor a bend upstream of the bifurcation leads to an avulsion within centuries as has been observed in some large rivers in tectonically inactive regions. On the other hand, a realistic tectonic uplift of the old branch or subsidence of the new branch may force an avulsion to take place quickly, and historical data show that the study area is seismically active. The combination of these factors leads to a realistic modeled avulsion duration of less than three centuries. Historical data indicate that these general conclusions might also apply to other large rivers in this region, e.g. the Brahmaputra and the Teesta. We conclude that large rivers may avulse quickly in response to tectonics but attain an anabranching pattern because of the large dimension of the residual channel and backwater effects.

  9. Seasonal cycle of precipitation over major river basins in South and Southeast Asia: A review of the CMIP5 climate models data for present climate and future climate projections

    Science.gov (United States)

    Lucarini, Valerio

    2017-04-01

    We review the skill of thirty coupled climate models participating in the Coupled Model Intercomparison Project Phase 5 (CMIP5) in terms of reproducing properties of the seasonal cycle of precipitation over the major river basins of South and Southeast Asia (Indus, Ganges, Brahmaputra and Mekong) for the historical period (1961-2000). We also present how these models represent the impact of climate change by the end of century (2061-2100) under the extreme scenario RCP8.5. First, we assess the models' ability to reproduce the observed timings of the monsoon onset and the rate of rapid fractional accumulation (RFA) slope — a measure of seasonality within the active monsoon period. Secondly, we apply a threshold-independent seasonality index (SI) — a multiplicative measure of precipitation (P) and extent of its concentration relative to uniform distribution (relative entropy — RE). We apply SI distinctly over the monsoonal precipitation regime (MPR), westerly precipitation regime (WPR) and annual precipitation. For the present climate, neither any single model nor the multi-model mean performs best in all chosen metrics. Models show overall a modest skill in suggesting right timings of the monsoon onset while the RFA slope is generally underestimated. One third of the models fail to capture the monsoon signal over the Indus basin. Mostly, the estimates for SI during WPR are higher than observed for all basins. When looking at MPR, the models typically simulate an SI higher (lower) than observed for the Ganges and Brahmaputra (Indus and Mekong) basins, following the pattern of overestimation (underestimation) of precipitation. Most of the models are biased negative (positive) for RE estimates over the Brahmaputra and Mekong (Indus and Ganges) basins, implying the extent of precipitation concentration for MPR and number of dry days within WPR lower (higher) than observed for these basins. Such skill of the CMIP5 models in representing the present-day monsoonal

  10. Wild and Scenic Rivers

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This map layer portrays the linear federally-owned land features (i.e., national parkways, wild and scenic rivers, etc.) of the United States, Puerto Rico, and the...

  11. The Carmans River Story

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — In this study, undertaken as an independent project at Bellport High School, the authors have attempted to provide a historical description of the Carmans River area...

  12. Management recommendations: Bear River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is a review of land management practices at the Bear River Migratory Bird Refuge, by a land use specialist. Recommendations, time frame and additional...

  13. River research programme

    CSIR Research Space (South Africa)

    Ferrar, AA

    1988-01-01

    Full Text Available The need for a comprehensive, multidisciplinary research programme for river ecosystems is described. The scope of the programme needs to include basic descriptions of a systems and biota, the testing and development of functional theory...

  14. Russian River Analysis

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is an analysis and summary of progress toward achieving the interim management objectives for the Russian River during the 1979 season. Additionally,...

  15. Connecticut River Hydrologic Observatory

    Science.gov (United States)

    Ballestero, T. P.

    2004-12-01

    The Connecticut River basin possesses some characteristics that make it unique for studying hydrologic issues that transcend scale. The watershed was first dramatically altered through natural processes (glaciation) and then heavily impacted by human stresses (dams, deforestation, acid precipitation/deposition), only to exhibit recent decades of return to a more natural state (reforestation, land conservation, stream restoration, pollution abatement, and dam removal). The watershed is sufficiently north to be classified as a cold region. More specifically to hydrology, the watershed exhibits the spectrum of flooding problems: ice dams, convective storms, hurricanes, rain on melting snow, and low pressure systems. The 28,000 square kilometer Connecticut River Watershed covers one third of the states of New Hampshire, Vermont, Massachusetts, and Connecticut. The >640-km long rivers' headwaters start on the Canadian border at the Fourth Connecticut Lake, and flows southward to discharge in Long Island sound. The lower 100 km of river are tidally influenced. The Connecticut River is responsible for 70 % of the freshwater inflow to Long Island Sound. The Connecticut River is a sixth order stream that exhibits a dendritic pattern in an elongated scheme. This setting therefore affords many first and second order streams in almost parallel fashion, flowing west or east towards the central Connecticut River spine. There are 38 major tributaries to the mainstem Connecticut River, and 26 of these tributaries drain greater than 250 square kilometers. There is in excess of 30,000 km of perennially flowing stream length in the watershed. For more information, see: http://www.unh.edu/erg/connho/

  16. The rivers of civilization

    Science.gov (United States)

    Macklin, Mark G.; Lewin, John

    2015-04-01

    The hydromorphic regimes that underpinned Old World river-based civilizations are reviewed in light of recent research. Notable Holocene climatic changes varied from region to region, whilst the dynamics of floodplain environments were equally diverse, with river channel changes significantly affecting human settlement. There were longer-term trends in Holocene hydroclimate and multi-centennial length 'flood-rich' and 'flood-poor' episodes. These impacted on five identified flooding and settlement scenarios: (i) alluvial fans and aprons; (ii) laterally mobile rivers; (iii) rivers with well-developed levees and flood basins; (iv) river systems characterised by avulsions and floodouts; and (v) large river-fed wetlands. This gave a range of changes that were either more or less regular or incremental from year-to-year (and thus potentially manageable) or catastrophic. The latter might be sudden during a flood event or a few seasons (acute), or over longer periods extending over many decades or even centuries (chronic). The geomorphic and environmental impacts of these events on riparian societies were very often irreversible. Contrasts are made between allogenic and autogenic mechanism for imposing environmental stress on riverine communities and a distinction is made between channel avulsion and contraction responses. Floods, droughts and river channel changes can precondition as well as trigger environmental crises and societal collapse. The Nile system currently offers the best set of independently dated Holocene fluvial and archaeological records, and the contrasted effects of changing hydromorphological regimes on floodwater farming are examined. The persistence of civilizations depended essentially on the societies that maintained them, but they were also understandably resilient in some environments (Pharaonic Egypt in the Egyptian Nile), appear to have had more limited windows of opportunity in others (the Kerma Kingdom in the Nubian Nile), or required

  17. Wind River: A Wild and Scenic River Analysis: Preliminary draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Wind River meets the criteria for inclusion in the National Wild and Scenic Rivers System. Subject to valid existing rights, the minerals in Federal lands which...

  18. The Colorado River

    Science.gov (United States)

    2002-01-01

    This Moderate-resolution Imaging Spectroradiometer (MODIS) true-color image shows the passage of the Colorado River through several southwestern states. The river begins, in this image, in Utah at the far upper right, where Lake Powell is visible as dark pixels surrounded by the salmon-colored rocks of the Colorado Plateau. The Colorado flows southwest through Glen Canyon, to the Glen Canyon Dam, on the Utah-Arizona border. From there it flows south into Arizona, and then turns sharply west where the Grand Canyon of the Colorado cuts through the mountains. The Colorado flows west to the Arizona-Nevada (upper left) border, where it is dammed again, this time by the Hoover Dam. The dark-colored pixels surrounding the bend in the river are Lake Mead. The river flows south along the border of first Nevada and Arizona and then California and Arizona. The Colorado River, which begins in Rocky Mountain National Park in Colorado, empties into the Gulf of California, seen at the bottom center of this image.

  19. 50 CFR 226.205 - Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River...

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 7 2010-10-01 2010-10-01 false Critical habitat for Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook salmon. 226.205 Section... Snake River sockeye salmon, Snake River fall chinook salmon, and Snake River spring/summer chinook...

  20. 33 CFR 207.380 - Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Red Lake River, Minn.; logging... Red Lake River, Minn.; logging regulations for portion of river above Thief River Falls. (a) Parties wishing to run logs on Red Lake River must provide storage booms near the head of the river to take care...

  1. 33 CFR 117.734 - Navesink River (Swimming River).

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Navesink River (Swimming River). 117.734 Section 117.734 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... (Swimming River). The Oceanic Bridge, mile 4.5, shall open on signal; except that, from December 1 through...

  2. Skjern River Restoration Counterfactual

    DEFF Research Database (Denmark)

    Clemmensen, Thomas Juel

    2014-01-01

    of Dissonance in Nature Restoration’, Journal of Landscape Architecture 2/2014: 58-67. Danish Nature Agency (2005), Skjern Å: Ådalens historie. De store projekter. Det nye landskab og naturen. På tur i ådalen [The Skjern River: The History of the River Delta. The Big Projects. The New Landscape and Nature......In 2003 the Skjern River Restoration Project in Denmark was awarded the prestigious Europa Nostra Prize for ‘conserving the European cultural heritage’ (Danish Nature Agency 2005). In this case, however, it seems that the conservation of one cultural heritage came at the expense of another cultural...... history and more openness towards constant change. In this approach the idea of palimpsest as metaphor for the cultural landscape plays an important role. Rather than being an obstacle for the restoration of nature, the historical layer following the comprehensive cultivation project from the 1960s...

  3. Missouri River 1943 Compact Line

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — Flood Control, Bank Stabilization and development of a navigational channel on the Missouri River had a great impact on the river and adjacent lands. The new...

  4. Sprague River Oregon Bars 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  5. Sprague River Oregon Centerline 2005

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  6. Sprague River Oregon Floodplain 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  7. Sprague River Oregon Floodplain 1940

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  8. Sprague River Oregon Centerline 2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  9. Sprague River Oregon Centerline 1975

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  10. Haw River PFCs Data Set

    Data.gov (United States)

    U.S. Environmental Protection Agency — PFAS concentrations in river and drinking water in and around the Haw River in North Carolina. This dataset is associated with the following publication: Sun, M., E....

  11. Sprague River Oregon Centerline 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  12. Two Pontic rivers

    DEFF Research Database (Denmark)

    Bekker-Nielsen, Tønnes; Jensen, Marit

    2015-01-01

    The accounts of the landscape around the Iris (Yeşilirmak) and the Thermodon (Terme) given by ancient authors are diverse and often contradictory. The Periegesis of the World by Dionysius of Alexandria, a didactic poem written in the early IInd c. A.D., established an image of the two rivers...... that does not correspond to their actual characteristics. A closer study reveals that Dionysius, or possibly his source, has confused the two: the river which he describes as the Thermodon is in fact the Iris, and vice versa. This mistake was not realized by later translators (Avienus, late IVth c. A...

  13. Nowitna River goose survey, 1986

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — An aerial goose survey of the upper Nowitna River and a river-floating goose brood survey of the upper Nowitna River were conducted May 27th through July 5th of...

  14. Stochastic Modelling of River Geometry

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Schaarup-Jensen, K.

    1996-01-01

    Numerical hydrodynamic river models are used in a large number of applications to estimate critical events for rivers. These estimates are subject to a number of uncertainties. In this paper, the problem to evaluate these estimates using probabilistic methods is considered. Stochastic models for ...... for river geometries are formulated and a coupling between hydraulic computational methods and numerical reliability methods is presented....

  15. Geomorphic classification of rivers

    Science.gov (United States)

    J. M. Buffington; D. R. Montgomery

    2013-01-01

    Over the last several decades, environmental legislation and a growing awareness of historical human disturbance to rivers worldwide (Schumm, 1977; Collins et al., 2003; Surian and Rinaldi, 2003; Nilsson et al., 2005; Chin, 2006; Walter and Merritts, 2008) have fostered unprecedented collaboration among scientists, land managers, and stakeholders to better understand,...

  16. The River Rock School.

    Science.gov (United States)

    Gereaux, Teresa Thomas

    1999-01-01

    In the early 1920s, the small Appalachian community of Damascus, Virginia, used private subscriptions and volunteer labor to build a 15-classroom school made of rocks from a nearby river and chestnut wood from nearby forests. The school building's history, uses for various community activities, and current condition are described. (SV)

  17. Discover the Nile River

    Science.gov (United States)

    Project WET Foundation, 2009

    2009-01-01

    Bordering on the Fantastic. As the longest river on earth, the Nile passes through 10 countries. Presented through a wide range of activities and a winning array of games, it's also unsurpassed at taking young minds into exploring the world of water, as well as natural and man made wonders.

  18. Laboratory Alluvial Rivers

    Science.gov (United States)

    Devauchelle, O.; Abramian, A.; Seizilles, G.; Lajeunesse, E.

    2015-12-01

    By which physical mechanisms does a river select its shape and size? We investigate this question using small laboratory rivers formed by laminar flows.In its simplest form, this experiment consists in a flow of glycerol over a uniform layer of plastic sediments. After a few hours, a channel forms spontaneously, and eventually reaches a stable geometry. This equilibrium state corresponds accurately to the force balance proposed by Henderson (1961).If we impose a sediment discharge at the inlet of the experiment, the river adjusts to this boundary condition by widening its channel. Observation suggests that this new equilibrium results from the balance between gravity, which pulls the entrained grains towards the center of the channel, and bedload diffusion, which returns them towards the banks. This balance explains why experimental rivers get wider and shallower as their sediment load increases.However, to test quantitatively this theory against observation, we need to evaluate independently the effect of transverse slope on bedload transport. We propose to use an instability generated by bedload diffusion to do so.

  19. River Out of Edenl

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 11. River Out of Eden Darwin Goes Digital: Old View, New Metaphor. J A Santosh. Book Review Volume 2 Issue 11 November 1997 pp 104-106. Fulltext. Click here to view fulltext PDF. Permanent link:

  20. communities of rivers, nigeria

    African Journals Online (AJOL)

    daily by noise pollution and other health hazards. They drink from the very rivers and rivulets which have been polluted by petroleum extracts making development difficult. The sum total of all development objectives is to make life more meaningful and allow the people feel the impact of the “new dawn" of development.

  1. River Pollution: Part I.

    Science.gov (United States)

    Openshaw, Peter

    1983-01-01

    Describes a unit on river pollution and analytical methods to use in assessing temperature, pH, flow, calcium, chloride, dissolved oxygen, biochemical oxygen demand, dissolved nitrogen, detergents, heavy metals, sewage pollution, conductivity, and sediment cores. Suggests tests to be carried out and discusses significance of results. (JM)

  2. The Mtata River estuary

    African Journals Online (AJOL)

    1989-02-28

    Feb 28, 1989 ... A survey of the fish fauna of Transkei estuaries. Part Three: The Mtata River estuary. E.E. Plumstead* and J.F. Prinsloo. Department of Zoology, University of Transkei, Private Bag X1 001, Unitra, Umtata, Republic of Transkei. H.J. Schoonbee. Department of Zoology, Rand Afrikaans University, P.O. Box 524, ...

  3. The Hudson River estuary

    National Research Council Canada - National Science Library

    Levinton, J.S; Waldman, J.R

    2006-01-01

    ... emphasis on important issues specific to the Hudson, such as the effect of power plants and high concentrations of PCBs. The chapters are written by specialists at a level that is accessible to students, teachers, and the interested layperson. The Hudson River Estuary is a unique scientifi c biography of a major estuary, with relevance to the s...

  4. River water pollution condition in upper part of Brantas River and Bengawan Solo River

    Science.gov (United States)

    Roosmini, D.; Septiono, M. A.; Putri, N. E.; Shabrina, H. M.; Salami, I. R. S.; Ariesyady, H. D.

    2018-01-01

    Wastewater and solid waste from both domestic and industry have been known to give burden on river water quality. Most of river water quality problem in Indonesia has start in the upper part of river due to anthropogenic activities, due to inappropriate land use management including the poor wastewater infrastructure. Base on Upper Citarum River Water pollution problem, it is interesting to study the other main river in Java Island. Bengawan Solo River and Brantas River were chosen as the sample in this study. Parameters assessed in this study are as follows: TSS, TDS, pH, DO, and hexavalent chromium. The status of river water quality are assess using STORET method. Based on (five) parameters, STORET value showed that in Brantas River, Pagerluyung monitoring point had the worst quality relatively compared to other monitoring point in Brantas River with exceeding copper, lead and tin compared to the stream standard in East Java Provincial Regulation No. 2 in 2008. Brantas River was categorized as lightly polluted river based on monitoring period 2011-2015 in 5 monitoring points, namely Pendem, Sengguruh, Kademangan, Meritjan and Kertosono.

  5. Dynamic reorganization of river basins.

    Science.gov (United States)

    Willett, Sean D; McCoy, Scott W; Perron, J Taylor; Goren, Liran; Chen, Chia-Yu

    2014-03-07

    River networks evolve as migrating drainage divides reshape river basins and change network topology by capture of river channels. We demonstrate that a characteristic metric of river network geometry gauges the horizontal motion of drainage divides. Assessing this metric throughout a landscape maps the dynamic states of entire river networks, revealing diverse conditions: Drainage divides in the Loess Plateau of China appear stationary; the young topography of Taiwan has migrating divides driving adjustment of major basins; and rivers draining the ancient landscape of the southeastern United States are reorganizing in response to escarpment retreat and coastal advance. The ability to measure the dynamic reorganization of river basins presents opportunities to examine landscape-scale interactions among tectonics, erosion, and ecology.

  6. The fluvial geochemistry, contributions of silicate, carbonate and saline-alkaline components to chemical weathering flux and controlling parameters: Narmada River (Deccan Traps), India

    Science.gov (United States)

    Gupta, Harish; Chakrapani, Govind J.; Selvaraj, Kandasamy; Kao, Shuh-Ji

    2011-02-01

    and PWR. On the basis of observed wide temporal variations in the CWR and their close association with runoff, temperature and physical erosion, we propose that the CWR in the Narmada basin strongly depend on meteorological variability. At most locations, the total denudation rates (TDR) are dominated by physical erosion, whereas chemical weathering constitutes only a small part (New Zealand (1-5%) and large Himalayan Rivers such as the Brahmaputra and the Ganges (8-9%).

  7. Anticipating Central Asian Water Stress: Variation in River Flow Dependency on Melt Waters from Alpine to Plains in the Remote Tien Shan Range, Kyrgyzstan Using a Rapid Hydro Assessment Methodology

    Science.gov (United States)

    Hill, A. F.; Wilson, A. M.; Williams, M. W.

    2016-12-01

    The future of mountain water resources in High Asia is of high interest to water managers, development organizations and policy makers given large populations downstream reliant on snow and ice sourced river flow. Together with historical and cultural divides among ex-Soviet republics, a lack of central water management following the Soviet break-up has led to water stress as trans-boundary waters weave through and along borders. New upstream hydropower development, a thirsty downstream agricultural sector and a shrinking Aral Sea has led to increasing tension in the region. Despite these pressures and in contrast to eastern High Asia's Himalayan basins (Ganges, Brahmaputra), little attention has been given to western High Asia draining the Pamir and Tien Shan ranges (Syr Darya and Amu Darya basins) to better understand the hydrology of this vast and remote area. Difficult access and challenging terrain exacerbate challenges to working in this remote mountain region. As part of the Contributions to High Asia Runoff from Ice and Snow (CHARIS) project, we asked how does river flow source water composition change over an alpine-to-plains domain of Kyrgyzstan's Naryn River in the Syr Darya basin? In addition, what may the future hold for river flow in Central Asia given the differing responses of snow and ice to climate changes? Utilizing a Rapid Hydrologic Assessment methodology including a suite of pre-field mapping techniques we collected in situ water chemistry data at targeted, remote mountain sites over 450km of the Naryn River over an elevation gradient from glacial headwaters to the lower lying areas - places where people, hydropower and agriculture utilize water. Chemical and isotope tracers were used to separate stream flow to understand relative dependency on melt waters as the river moves downstream from glaciers and snow covered areas. This case study demonstrates a technique to acquire field data over large scales in remote regions that facilitates

  8. River-corridor habitat dynamics, Lower Missouri River

    Science.gov (United States)

    Jacobson, Robert B.

    2010-01-01

    Intensive management of the Missouri River for navigation, flood control, and power generation has resulted in substantial physical changes to the river corridor. Historically, the Missouri River was characterized by a shifting, multithread channel and abundant unvegetated sandbars. The shifting channel provided a wide variety of hydraulic environments and large areas of connected and unconnected off-channel water bodies.Beginning in the early 1800s and continuing to the present, the channel of the Lower Missouri River (downstream from Sioux City, Iowa) has been trained into a fast, deep, single-thread channel to stabilize banks and maintain commercial navigation. Wing dikes now concentrate the flow, and revetments and levees keep the channel in place and disconnect it from the flood plain. In addition, reservoir regulation of the Missouri River upstream of Yankton, South Dakota, has substantially changed the annual hydrograph, sediment loads, temperature regime, and nutrient budgets.While changes to the Missouri River have resulted in broad social and economic benefits, they have also been associated with loss of river-corridor habitats and diminished populations of native fish and wildlife species. Today, Missouri River stakeholders are seeking ways to restore some natural ecosystem benefits of the Lower Missouri River without compromising traditional economic uses of the river and flood plain.

  9. Geomorphology and River Management

    Directory of Open Access Journals (Sweden)

    GARY BRIERLEY

    2008-01-01

    Full Text Available Engineering-dominated practices, visible in a "command and control" outlook on natural systems, have induced enormous damage to the environment. Biodiversity losses and declining provision of ecosystem services are testimony to the non-sustainable outcomes brought about by such practices. More environmentally friendly approaches that promote a harmonious relationship between human activities and nature are required. Moves towards an "ecosystem approach" to environmental management require coherent (integrative scientific guidance. Geomorphology, the study of the form of the earth, provides a landscape template with which to ground this process. This way of thinking respects the inherent diversity and complexity of natural systems. Examples of the transition toward such views in environmental practice are demonstrated by the use of science to guide river management, emphasising applications of the River Styles framework.

  10. Re: Soviet river diversions

    Science.gov (United States)

    Robertson, Jas O.

    The paper on ‘Soviet River Diversions’ by Phil Micklin (Eos, 62(19), May 12, 1981) has just come to hand.Referring to the map on page 489, I was interested to see the estimates of river flows for the Amu and Syr Darya, which clearly show the effect of irrigation on inflows to the Aral Sea. Recently, I was passing over the northeast corner of the sea on a flight from Tashkent to Moscow when I got the impression that increasing irrigation development on the Syr Darya is likely to decrease the annual inflow even more than in the recent past. The same state of affairs has been going on in the Caspian Sea for years, as a result of irrigation development on the Volga. My impression was that the Aral Sea had shrunk considerably from the 26,000 odd square miles (67,304 km2) area quoted (from memory) in Encyclopaedia Britannica (edition circa 1970).

  11. The river research programme

    CSIR Research Space (South Africa)

    Ferrar, AA

    1988-01-01

    Full Text Available reference to the ecological needs of aquatic ecosystems. No acknowledgement of any social or economic cost for the degradation of aquatic ecosystems as a result of water abstraction is made in the Commission's report except for certain nature reserves... for water means that all our substantial river systems will be subject to water regulation and abstraction and to the introduction of pollutants. Conservation management therefore becomes an exercise in mitigation. The principal tools are, legislation...

  12. Bridging the Past with Today's Microwave Remote Sensing: A Case Study of Long Term Inundation Patterns in Two River Deltas

    Science.gov (United States)

    McDonald, K. C.; Jensen, K.; Schroeder, R.; Tessler, Z. D.

    2016-12-01

    Surface inundation extent and its predictability vary tremendously across the globe. This dynamic is being and has been captured by three general categories of satellite imagery: a) low-spatial-resolution microwave sensors with global coverage and a long record of observations (e.g., SSM/I), b) optical sensors with high spatial and temporal resolution and global coverage as well, but with cloud contamination (e.g. MODIS), and also c) less frequently in ``snapshot'' form by high-resolution synthetic aperture radar (SAR) sensors. We explore the ability to bridge techniques that can exploit the higher spatial resolution of more recent data products back in time with the help of the temporal evolution of lower resolution products. We present a study of long term (20+ yrs) inundation patterns in two river deltas: (1) the Mekong, and (2) the Ganges-Brahmaputra. This research utilizes baseline observations from the Surface Water Microwave Product Series (SWAMPS), an inundation area fraction product derived at 25km scale from active and passive microwave instruments (ERS, QuikSCAT, ASCAT, and SSM/I) that spans from Jan 1992 to the present. Every hydrological basin has unique characteristics - such as its topography, land cover / land use, and spatio-temporal variability - thus, a downscaling algorithm needs to take into account these idiosyncrasies. We merge SWAMPS with topographical information derived from 30m SRTM DEM, river networks from USGS HydroSHEDS, and train a downscaling algorithm to learn from two sets of classified SAR data: (1) L-band imaging radar from ALOS PALSAR, 2007-2010, and (2) more recent C-band imagery from the Sentinel-1 mission (2014 to present). We present an accuracy assessment of retrospective downscaled flood extent with Landsat imagery and address potential sources of biases. With a higher spatial resolution of past flooding extent, we can improve our understanding of how delta surface hydrology has responded to climate events and human

  13. Rehabilitating China's largest inland river.

    Science.gov (United States)

    Li, Yiqing; Chen, Yaning; Zhang, Yaoqi; Xia, Yang

    2009-06-01

    Wetlands are particularly important for conserving China's biodiversity but riparian wetlands in the Tarim River basin in western China have been reduced by 46% during the last 3 decades. The world's largest habitat for Populus euphratica, which is in the Tarim River basin, significantly shrank. To protect and restore the deteriorated ecosystems along the Tarim River and its associated wetlands, China's government initiated a multimillion dollar river restoration project to release water from upper dams to the dried-up lower reaches of the Tarim River starting in 2000. We monitored the responses of groundwater and vegetation to water recharge in the lower reaches of the river from 2000 to 2006 by establishing nine 1000-m-long transects perpendicular to the river at intervals of 20-45 km along the 320-km river course below the Daxihaizi Reservoir, the source of water conveyance, to Lake Taitema, the terminus of the Tarim River. Water recharges from the Daxihaizi Reservoir to the lower reaches of the Tarim River significantly increased groundwater levels and vegetation coverage at all monitoring sites along the river. The mean canopy size of the endangered plant species P. euphratica doubled after 6 years of water recharge. Some rare migrating birds returned to rest on the restored wetlands in summer along the lower reaches of the Tarim River. The biggest challenge facing decision makers, however, is to balance water allocation and water rights between agricultural and natural ecosystems in a sustainable way. A large number of inhabitants in the Tarim Basin depend on these limited water resources for a living. At the same time, the endangered ecosystems need to be protected. Given the ecological, socioeconomic, and sociopolitical realities in the Tarim Basin, adaptive water policies and strategies are needed for water allocation in these areas of limited water resources. ©2009 Society for Conservation Biology.

  14. Natural transformation in river epilithon.

    OpenAIRE

    Williams, H. G.; Day, M.J.; Fry, J. C.; Stewart, G. J.

    1996-01-01

    Natural transformation was demonstrated in unenclosed experiments incubated in river epilithon. Strains of Acinetobacter calcoaceticus were transformed to prototrophy by either free DNA (lysates) or live donor cells. The sources of transforming DNA and recipient culture were immobilized on filters, secured to stones, and incubated midstream in the river. The transfer frequency generally increased with temperature. No transfer was detected in the river Taff below 10 degrees C. The age of the r...

  15. ENGINEER SUPPORT OF RIVER CROSSINGS,

    Science.gov (United States)

    The author discusses the basic missions of engineer support in forcing rivers from a drive, following planned preparations, and under special...conditions. Practical recommendations are made with respect to organizing engineer support in forcing rivers and the characteristics of crossing means is described. (Author)

  16. Niagara River Toxics Management Plan

    Science.gov (United States)

    This 2007 Progress Report of the Niagara River Toxics Management Plan (NRTMP) summarizes progress made by the four parties in dealing with the 18 “Priority Toxics” through reductions in point and non-point sources to the Niagara River.

  17. Morphodynamics: Rivers beyond steady state

    National Research Council Canada - National Science Library

    Church, M; Ferguson, R. I

    2015-01-01

    .... River morphodynamics—an expression of bed material erosion, transport, and deposition—is the study of these interactions, the outcome of which is river morphology, hence it is appropriate to consider together advances in understanding bed material transport and morphodynamics. Over the past half century, Water Resources Research has been a significan...

  18. Geomorphology and River Dynamics of the Lower Copper River, Alaska

    Science.gov (United States)

    Brabets, Timothy P.; Conaway, Jeffrey S.

    2009-01-01

    Located in south-central Alaska, the Copper River drains an area of more than 24,000 square miles. The average annual flow of the river near its mouth is 63,600 cubic feet per second, but is highly variable between winter and summer. In the winter, flow averages approximately 11,700 cubic feet per second, and in the summer, due to snowmelt, rainfall, and glacial melt, flow averages approximately 113,000 cubic feet per second, an order of magnitude higher. About 15 miles upstream of its mouth, the Copper River flows past the face of Childs Glacier and enters a large, broad, delta. The Copper River Highway traverses this flood plain, and in 2008, 11 bridges were located along this section of the highway. The bridges cross several parts of the Copper River and in recent years, the changing course of the river has seriously damaged some of the bridges. Analysis of aerial photography from 1991, 1996, 2002, 2006, and 2007 indicates the eastward migration of a channel of the Copper River that has resulted in damage to the Copper River Highway near Mile 43.5. Migration of another channel in the flood plain has resulted in damage to the approach of Bridge 339. As a verification of channel change, flow measurements were made at bridges along the Copper River Highway in 2005-07. Analysis of the flow measurements indicate that the total flow of the Copper River has shifted from approximately 50 percent passing through the bridges at Mile 27, near the western edge of the flood plain, and 50 percent passing through the bridges at Mile 36-37 to approximately 5 percent passing through the bridges at Mile 27 and 95 percent through the bridges at Mile 36-37 during average flow periods. The U.S. Geological Survey's Multi-Dimensional Surface-Water Modeling System was used to simulate water-surface elevation and velocity, and to compute bed shear stress at two areas where the Copper River is affecting the Copper River Highway. After calibration, the model was used to examine the

  19. Hood River Passive House

    Energy Technology Data Exchange (ETDEWEB)

    Hales, David [BA-PIRC, Spokane, WA (United States)

    2014-01-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to "reduce home energy use by 30%-50% (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

  20. Hood River Passive House

    Energy Technology Data Exchange (ETDEWEB)

    Hales, David [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2014-01-01

    The Hood River Passive Project was developed by Root Design Build of Hood River Oregon using the Passive House Planning Package (PHPP) to meet all of the requirements for certification under the European Passive House standards. The Passive House design approach has been gaining momentum among residential designers for custom homes and BEopt modeling indicates that these designs may actually exceed the goal of the U.S. Department of Energy's (DOE) Building America program to reduce home energy use by 30%-50% (compared to 2009 energy codes for new homes). This report documents the short term test results of the Shift House and compares the results of PHPP and BEopt modeling of the project. The design includes high R-Value assemblies, extremely tight construction, high performance doors and windows, solar thermal DHW, heat recovery ventilation, moveable external shutters and a high performance ductless mini-split heat pump. Cost analysis indicates that many of the measures implemented in this project did not meet the BA standard for cost neutrality. The ductless mini-split heat pump, lighting and advanced air leakage control were the most cost effective measures. The future challenge will be to value engineer the performance levels indicated here in modeling using production based practices at a significantly lower cost.

  1. River-Based Experiential Learning: the Bear River Fellows Program

    Science.gov (United States)

    Rosenberg, D. E.; Shirley, B.; Roark, M. F.

    2012-12-01

    The Department of Civil and Environmental Engineering, Outdoor Recreation, and Parks and Recreation programs at Utah State University (USU) have partnered to offer a new, unique river-based experiential learning opportunity for undergraduates called the Bear River Fellows Program. The program allows incoming freshmen Fellows to experience a river first hand during a 5-day/4-night river trip on the nearby Bear River two weeks before the start of their first Fall semester. As part of the program, Fellows will navigate the Bear River in canoes, camp along the banks, interact with local water and environmental managers, collect channel cross section, stream flow, vegetation cover, and topological complexity data, meet other incoming freshmen, interact with faculty and graduate students, develop boating and leadership skills, problem solve, and participate as full members of the trip team. Subsequently, Fellows will get paid as undergraduate researchers during their Fall and Spring Freshman semesters to analyze, synthesize, and present the field data they collect. The program is a collaborative effort between two USU academic units and the (non-academic) division of Student Services and supports a larger National Science Foundation funded environmental modelling and management project for the lower Bear River, Utah watershed. We have advertised the program via Facebook and emails to incoming USU freshmen, received 35 applications (60% women), and accepted 5 Fellows into the program (3 female and 2 male). The river trip departs August 14, 2012. The poster will overview the Bear River Fellows Program and present qualitative and preliminary outcomes emerging from the trip and Fellows' work through the Fall semester with the field data they collect. We will also undertake more rigorous and longer longitudinal quantitative evaluation of Program outcomes (for example, in problem-solving and leadership) both in Spring 2013 and in subsequent 2013 and 2014 offerings of the

  2. PCBs in the Harlem River

    Science.gov (United States)

    Wang, J.

    2012-12-01

    Polychlorinated biphenyls (PCBs) are persistent, toxic and bioaccumulated contaminants of great environmental concern. PCB is a tracer of wastewater, stormwater and CSOs inputs; PCBs contamination of fish is a main environmental concern for the Harlem River. PCBs in the Harlem River are from combined sewer overflows (CSOs), stormwater runoff, wastewater, as well as upper Hudson GE (General Electric at Fort Edward)'s release. PCBs affect human health mostly from contaminated fish consumption. Many research focused on PCBs in the Hudson River and New York/New Jersey Harbor. However, PCBs source, transport and environmental impact in the Harlem River-a natural straight that connects the Hudson River and the East River, had not been well studied. In this research, water sample were collected from the Harlem River and analyzed PCBs by HR GC/MS (High resolution gas chromatography mass spectrophotometer). Preliminary results showed that certain PCBs congeners in the water column. Results also indicated that nutrients (phosphorus and ammonia) as well as bacteria levels exceeded EPA standards: Total phosphorus-10μg/L, total nitrogen-0.38mg/L; E.Coli-126 MPN/100ml, Enterococcus- 104MPN/100ml, Fecal Coliform-200 MPN/100ml. This research is under process, and more results could give further detail in near future. This research will help improve water quality of the Harlem River, improve environmental health and raise environmental awareness.SO tank Nutrient and bacterial levels of selected sites in the Harlem RiverCSO: Combined Sewer OverflowWWTP: Waste Water Treatment Plant

  3. 29 CFR 1917.126 - River banks.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false River banks. 1917.126 Section 1917.126 Labor Regulations...) MARINE TERMINALS Terminal Facilities § 1917.126 River banks. (a) This section applies to temporary installations or temporary operations near a river bank. (b) Where working surfaces at river banks slope so...

  4. Clinch River project: Sediment contaminants in the Lower Clinch River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Sediment samples from three mainstem and seven tributary sites in the Clinch River Basin were analyzed for 21 organochlorine compounds, 19 metals, total volatile...

  5. A Review of Integrated River Basin Management for Sarawak River

    OpenAIRE

    Kuok K. Kuok; Sobri Harun; Po-Chan Chiu

    2011-01-01

    Problem statement: Sarawak River was a life-sustaining water source for the residents in Kuching City and surrounding areas. Raw water is treated at Batu Kitang Water Treatment Plant (BKWTP) that supplies more than 98% of the total water production in Kuching City. The raw water supply to BKWTP is not adequate to meet the ever increasing water demand. In order to overcome this problem, four projects had been implemented along Sarawak River for managing and securing water&#...

  6. Hydrological River Drought Analysis (Case Study: Lake Urmia Basin Rivers

    Directory of Open Access Journals (Sweden)

    Mohammad Nazeri Tahrudi

    2017-02-01

    Full Text Available Introduction: Drought from the hydrological viewpoint is a continuation of the meteorological drought that cause of the lack of surface water such as rivers, lakes, reservoirs and groundwater resources. This analysis, which is generally on the surface streams, reservoirs, lakes and groundwater, takes place as hydrological drought considered and studied. So the data on the quantity of flow of the rivers in this study is of fundamental importance. This data are included, level, flow, river flow is no term (5. Overall the hydrological drought studies are focused on annual discharges, maximum annual discharge or minimum discharge period. The most importance of this analysis is periodically during the course of the analysis remains a certain threshold and subthresholdrunoff volume fraction has created. In situations where water for irrigation or water of a river without any reservoir, is not adequate, the minimum flow analysis, the most important factor to be considered (4. The aim of this study is evaluatingthe statistical distributions of drought volume rivers data from the Urmia Lake’s rivers and its return period. Materials and Methods: Urmia Lake is a biggest and saltiest continued lake in Iran. The Lake Urmia basin is one of the most important basins in Iran region which is located in the North West of Iran. With an extent of 52700 square kilometers and an area equivalent to 3.21% of the total area of the country, This basin is located between the circuit of 35 degrees 40 minutes to 38 degrees 29 minutes north latitude and the meridian of 44 degrees 13 minutes to 47 degrees 53 minutes east longitude. In this study used the daily discharge data (m3s-1 of Urmia Lake Rivers. Extraction of river drought volume The drought durations were extracted from the daily discharge of 13 studied stations. The first mean year was calculated for each 365 days using the Eq 1 (14. (1 (For i=1,2,3,…,365 That Ki is aith mean year, Yijis ith day discharge in jth

  7. Challenges, Approaches and Experiences from Asian Deltas and the Rhine-Meuse Delta : Regional Training Workshop on Delta Planning and Management

    NARCIS (Netherlands)

    Wosten, J.H.M.; Douven, W.; Long Phi, H.; Fida Abdullah Khan, M.

    2013-01-01

    River delta's, like the Mekong Delta (Vietnam), Ganges-Brahmaputra Delta (Bangladesh), Ayeyarwady Delta (Myanmar), Nile (Egypt) and Ciliwung Delta (Indonesia) are developing rapidly and are characterised by large-scale urbanisation and industrialization processes. They are facing serious planning

  8. Haw River sediment quality assessment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report documents an evaluation of chemical contaminants in, and toxicity of, sediments collected from impoundments created by dams on the Haw River in Alamance...

  9. Umpqua River Oregon Geologic Floodplain

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of...

  10. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Department of Resources — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  11. Arkansas River Water Needs Assessment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report is on the legal elements, hydrologic analysis, objectives, and water levels related to the Arkansas River and the management of it.

  12. Braden River - Aerial Topographic Mapping

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This metadata record describes the ortho & LIDAR mapping of the Braden River area, FL. The mapping consists of LIDAR data collection, contour generation, and...

  13. Humboldt River main stem, Nevada

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This data set contains the main stem of the Humboldt River as defined by Humboldt Project personnel of the U.S. Geological Survey Nevada District, 2001. The data set...

  14. Togiak River sportfishing studies, 1984

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Nearly three thousand angler days of effort was estimated to have been spent on the Togiak River in 1984. Effort was clearly dominated by the professional guiding...

  15. Upper Yukon River, Alaska, a wild and scenic river analysis: Preliminary draft: Chapters IV and V

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Upper Yukon River, Alaska, possesses values which qualify it for inclusion in the National Wild and Scenic Rivers System. The Upper Yukon River and its immediate...

  16. Sensitivity of Coastal Environments and Wildlife to Spilled Oil: Hudson River: RVRMILES (River Mile Marker Lines)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains human-use resource data for river miles along the Hudson River. Vector lines in this data set represent river mile markers. This data set...

  17. Valley evolution by meandering rivers

    Science.gov (United States)

    Limaye, Ajay Brian Sanjay

    Fluvial systems form landscapes and sedimentary deposits with a rich hierarchy of structures that extend from grain- to valley scale. Large-scale pattern formation in fluvial systems is commonly attributed to forcing by external factors, including climate change, tectonic uplift, and sea-level change. Yet over geologic timescales, rivers may also develop large-scale erosional and depositional patterns that do not bear on environmental history. This dissertation uses a combination of numerical modeling and topographic analysis to identify and quantify patterns in river valleys that form as a consequence of river meandering alone, under constant external forcing. Chapter 2 identifies a numerical artifact in existing, grid-based models that represent the co-evolution of river channel migration and bank strength over geologic timescales. A new, vector-based technique for bank-material tracking is shown to improve predictions for the evolution of meander belts, floodplains, sedimentary deposits formed by aggrading channels, and bedrock river valleys, particularly when spatial contrasts in bank strength are strong. Chapters 3 and 4 apply this numerical technique to establishing valley topography formed by a vertically incising, meandering river subject to constant external forcing---which should serve as the null hypothesis for valley evolution. In Chapter 3, this scenario is shown to explain a variety of common bedrock river valley types and smaller-scale features within them---including entrenched channels, long-wavelength, arcuate scars in valley walls, and bedrock-cored river terraces. Chapter 4 describes the age and geometric statistics of river terraces formed by meandering with constant external forcing, and compares them to terraces in natural river valleys. The frequency of intrinsic terrace formation by meandering is shown to reflect a characteristic relief-generation timescale, and terrace length is identified as a key criterion for distinguishing these

  18. Impact of climate change on flood characteristics in Brahmaputra ...

    Indian Academy of Sciences (India)

    greater catastrophic disaster within the valley part due to higher volume of the flood wave discharge. Hence, the changes in monsoonal peak discharges are of greater concern for flood management in the basin. 4.6 Effect of climate change on the frequency of annual peak discharge. Return period analysis of the 30 years ...

  19. Impact of Ganges–Brahmaputra interannual discharge variations on ...

    Indian Academy of Sciences (India)

    in contrast with the available observations and is probably linked to the relatively coarse resolution of our model. However, the extreme ... conclusions, it appears necessary to use a numerical model with higher resolution (both on the horizontal and vertical) to ...... Nord; PhD thesis, University of Paris VI, 181 pp. Available on ...

  20. Impact of climate change on flood characteristics in Brahmaputra ...

    Indian Academy of Sciences (India)

    Future changes in the flood wave characteristics of the basin have been evaluated using the validated model with bias-corrected future-projected meteorological scenario from a regional climate model (RCM). Likelihood analysis of the simulated flow time series reveals that significant increase in both peak discharge and ...

  1. Holocene climatic fluctuations from Lower Brahmaputra flood plain ...

    Indian Academy of Sciences (India)

    Later, fluvial activity was succeeded by the tropical tree savanna under cool and dry climate between 12,700 and 11,600 cal years BP corresponding to that of global Younger Dryas. Between 11,600 and 8310 cal years BP, relatively less cool and dry climate prevailed with inception of tropical mixed deciduous taxa like ...

  2. Holocene climatic fluctuations from Lower Brahmaputra flood plain ...

    Indian Academy of Sciences (India)

    Warm Period and Little Ice Age (LIA) in this climatically sensitive region. According to some .... from within the forest across edge to open land. The surface samples DA-1 to DA-5 are procured from within forest, DA-6 to DA-7 from forest edge and DA-8 to DA-10 from open land, respectively. A 3.2-m deep sedimentary profile, ...

  3. Grays River Watershed Geomorphic Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Geist, David R

    2005-04-30

    This investigation, completed for the Pacific Northwest National Laboratory (PNNL), is part of the Grays River Watershed and Biological Assessment commissioned by Bonneville Power Administration under project number 2003-013-00 to assess impacts on salmon habitat in the upper Grays River watershed and present recommendations for habitat improvement. This report presents the findings of the geomorphic assessment and is intended to support the overall PNNL project by evaluating the following: The effects of historical and current land use practices on erosion and sedimentation within the channel network The ways in which these effects have influenced the sediment budget of the upper watershed The resulting responses in the main stem Grays River upstream of State Highway 4 The past and future implications for salmon habitat.

  4. Physical - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  5. Habitat Analysis - Trinity River Restoration Potential

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the Trinity River project is to identify the potential positive effects of large-scale restoration actions in a 63 kilometer reach of the Trinity River...

  6. Geomorphic Analysis - Trinity River Restoration Potential

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The goal of the Trinity River project is to identify the potential positive effects of large-scale restoration actions in a 63 kilometer reach of the Trinity River...

  7. Colorado River Mile System, Tenths of Miles

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This coverage contains points representing tenth of miles in the GCMRC river mile system. The points fall along the centerline of the Colorado River from Glen Canyon...

  8. Sprague River Oregon Centerline Sycan 2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  9. Sprague River Oregon Centerline North Fork 2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  10. 2010 Hudson River Shallow Water Sediment Cores

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hudson River Shallow Water Mapping project characterizes the bottom of the Hudson River Estuary in shallow water (<3 m). The characterization includes...

  11. 2010 Hudson River Shallow Water Sediment Grabs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Hudson River Shallow Water Mapping project characterizes the bottom of the Hudson River Estuary in shallow water (<3 m). The characterization includes...

  12. Global Lake and River Ice Phenology Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Lake and River Ice Phenology Database contains freeze and thaw/breakup dates as well as other descriptive ice cover data for 865 lakes and rivers in the...

  13. Russian River Ice Thickness and Duration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of river ice thickness measurements, and beginning and ending dates for river freeze-up events from fifty stations in northern Russia. The...

  14. Sprague River Oregon Built Features 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  15. Sprague River Oregon Centerline North Fork 2005

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  16. Sprague River Oregon Centerline North Fork 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  17. Sprague River Oregon Centerline Sycan 1940

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  18. Sprague River Oregon Centerline Sycan 2005

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  19. Lower Duck River Mussel Survey and Inventory

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Duck River flows 290 miles through several major ecoregions before entering the impounded main stem Tennessee River at Sycamore Landing, Tennessee, adjacent to...

  20. Sprague River Oregon Centerline North Fork 1975

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  1. Sprague River Oregon Centerline Sycan circa 1870

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  2. Sprague River Oregon Centerline Sycan 1968

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  3. Sprague River Oregon Built Features 1940

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  4. Sprague River Oregon Centerline South Fork 1975

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  5. Sprague River Oregon Centerline Sycan 1975

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  6. An expanded role for river networks

    Science.gov (United States)

    Jonathan P. Benstead; David S. Leigh

    2012-01-01

    Estimates of stream and river area have relied on observations at coarse resolution. Consideration of the smallest and most dynamic streams could reveal a greater role for river networks in global biogeochemical cycling than previously thought.

  7. A stochastic model of river discharge fluctuations

    Science.gov (United States)

    Livina, V.; Ashkenazy, Y.; Kizner, Z.; Strygin, V.; Bunde, A.; Havlin, S.

    2003-12-01

    We study the daily river flow fluctuations of 30 international rivers. Using the detrended fluctuation analysis, we study the correlations in the magnitudes of river flow increments (volatilities), and find power-law correlations in volatilities for time scales less than 1 year; these correlations almost disappear for time scales larger than 1 year. Using surrogate data test for nonlinearity, we show that correlations in the magnitudes of river flow fluctuations are a measure for nonlinearity. We propose a simple nonlinear stochastic model for river flow fluctuations that reproduces the main scaling properties of the river flow series as well as the correlations and periodicities in the magnitudes of river flow increments. According to our model, the source of nonlinearity observed in the data is an interaction between a long-term correlated process and the river discharge itself.

  8. Chemical - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  9. Biological - Elwha River Dam Removal Study

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study examines the ecosystem response of the Elwha River to the removal of the Elwha River dams. We will measure the following attributes of ecosystem response:...

  10. Minnesota Wild and Scenic River Districts

    Data.gov (United States)

    Minnesota Department of Natural Resources — District boundaries for wild, scenic, and recreational rivers designated under the Minnesota State Wild and Scenic Rivers Act. Includes portions of the Minnesota...

  11. Sprague River Oregon Centerline South Fork 1940

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Sprague River drains 4090 square kilometers in south-central Oregon before flowing into the Williamson River and upper Klamath Lake. In cooperation with the U.S....

  12. ALWAYS A RIVER - SUPPLEMENTAL ENVIRONMENTAL EDUCATION CURRICULUM ON THE OHIO RIVER AND WATER GRADES K - 12

    Science.gov (United States)

    This curriculum was developed as a significant component of the project, Always a River: The Ohio River and the American Experience, a six-state collaboration devoted to exploring the historical and cultural development of the Ohio River. The Always a River project is being joint...

  13. Many rivers to cross: Cross border co-operation in river management

    NARCIS (Netherlands)

    Verwijmeren, J.A.; Wiering, M.A.

    2007-01-01

    River basin management is a key concept in contemporary water policy. Since the management of rivers is best designed and implemented at the scale of the river basin, it seems obvious that we should not confine ourselves to administrative or geographical borders. In other words, river basin

  14. 78 FR 17087 - Special Local Regulation; New River Raft Race, New River; Fort Lauderdale, FL

    Science.gov (United States)

    2013-03-20

    ... Fort Lauderdale New River Raft Race, on Saturday, March 23, 2013. The special local regulation is... waterway of the United States during the Rotary Club of Fort Lauderdale New River Raft Race. On March 23... SECURITY Coast Guard 33 CFR Part 100 RIN 1625-AA08 Special Local Regulation; New River Raft Race, New River...

  15. 77 FR 45653 - Yakima River Basin Conservation Advisory Group; Yakima River Basin Water Enhancement Project...

    Science.gov (United States)

    2012-08-01

    ... Conservation Advisory Group; Yakima River Basin Water Enhancement Project, Yakima, WA AGENCY: Bureau of... Committee Act, the Yakima River Basin Conservation Advisory Group, Yakima River Basin Water Enhancement... River Basin Water Conservation Program. DATES: The meeting will be held on Tuesday, August 21, 2012...

  16. Columbia River Component Data Evaluation Summary Report

    Energy Technology Data Exchange (ETDEWEB)

    C.S. Cearlock

    2006-08-02

    The purpose of the Columbia River Component Data Compilation and Evaluation task was to compile, review, and evaluate existing information for constituents that may have been released to the Columbia River due to Hanford Site operations. Through this effort an extensive compilation of information pertaining to Hanford Site-related contaminants released to the Columbia River has been completed for almost 965 km of the river.

  17. 33 CFR 117.1058 - Snake River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake River. 117.1058 Section 117... OPERATION REGULATIONS Specific Requirements Washington § 117.1058 Snake River. (a) The draw of the Burlington Northern Santa Fe railroad bridge across the Snake River at mile 1.5 between Pasco and Burbank is...

  18. The science and practice of river restoration

    Science.gov (United States)

    Wohl, Ellen; Lane, Stuart N.; Wilcox, Andrew C.

    2015-08-01

    River restoration is one of the most prominent areas of applied water-resources science. From an initial focus on enhancing fish habitat or river appearance, primarily through structural modification of channel form, restoration has expanded to incorporate a wide variety of management activities designed to enhance river process and form. Restoration is conducted on headwater streams, large lowland rivers, and entire river networks in urban, agricultural, and less intensively human-altered environments. We critically examine how contemporary practitioners approach river restoration and challenges for implementing restoration, which include clearly identified objectives, holistic understanding of rivers as ecosystems, and the role of restoration as a social process. We also examine challenges for scientific understanding in river restoration. These include: how physical complexity supports biogeochemical function, stream metabolism, and stream ecosystem productivity; characterizing response curves of different river components; understanding sediment dynamics; and increasing appreciation of the importance of incorporating climate change considerations and resiliency into restoration planning. Finally, we examine changes in river restoration within the past decade, such as increasing use of stream mitigation banking; development of new tools and technologies; different types of process-based restoration; growing recognition of the importance of biological-physical feedbacks in rivers; increasing expectations of water quality improvements from restoration; and more effective communication between practitioners and river scientists.

  19. Water quality of the Modder River

    Directory of Open Access Journals (Sweden)

    N. Koning

    1999-07-01

    Full Text Available Seasonal and spatial patterns in the Modder River system, the influence of Botshabelo's sewage outflow’ on the water quality of the river, as well as the presence of any toxic compounds were determined. The Modder and Klein Modder Rivers do not follow distinctive seasonal patterns in terms of chemical parameters.

  20. The Nile River and Egyptian Foreign Policy

    African Journals Online (AJOL)

    percent of the territory fall within the Nile River basin (FAO 1997). The percentage of. Egypt's population in the Nile River basin accounts for more than 85 ..... Kagera, which flows into Lake Victoria, recognised the equitable utilisation of the river in such a way that would not jeopardise the interests of other fluvial states. Third,.

  1. Forms of Nutrients in Rivers Flowing into Lake Chaohu: A Comparison between Urban and Rural Rivers

    Directory of Open Access Journals (Sweden)

    Lei Zhang

    2015-08-01

    Full Text Available Nutrient inputs from rivers play an important role in lake eutrophication. To compare the forms characteristics of phosphorus (P and nitrogen (N in rivers flowing through rural and urban areas, water samples were collected seasonally from five urban rivers and six rural rivers flowing to Lake Chaohu, China. Higher total phosphorus (TP, particulate phosphorus (PP, soluble reactive phosphorus (SRP, and dissolved nonreactive phosphorus (DNP concentrations and SRP/TP percentages were observed in urban rivers than in rural rivers, and PP/TP and DNP/TP ratios were lower in urban rivers than in rural rivers. The concentrations of total nitrogen (TN and all N forms other than dissolved organic nitrogen (DON were significantly higher in urban rivers than in rural rivers. NH4+/TN levels were higher in urban rivers, whereas PN/TN and DON/TN ratios were significantly lower in urban rivers compared with rural rivers. NO3−/TN and NO2−/TN levels were similar between the two groups of rivers. TP, BD-P, and NaOH-P levels in urban river surface sediments were significantly higher than those in rural rivers. NaOH-P/TP ratios were significantly elevated in urban rivers, whereas HCl-P/TP and Res-P/TP ratios were significantly lower compared with rural rivers. Urban rivers have transferred large quantities of NH4+ and SRP into Lake Chaohu, resulting in higher TP and TN levels and NH4+/TN and SRP/TP ratios. Decreasing the input of NH4+ and SRP into urban rivers is a high priority for mitigating eutrophication and algal blooms in Lake Chaohu.

  2. from cross river estuary, nigeria

    African Journals Online (AJOL)

    U,F1,:1.,U_ rt as so. 75 $00 o 25 so 15 109 i. FIG. 3: VARIATION IN STOMACH FULLNESS OF PELLONULA Ieonesis FROM CROSS. RIVER ESTUARY, NIGERIA WITH SEXES, SIZES AND SEASONS. Results on ontogenetic diet composition shows that LSG ate more preyfishes and ants than. 886 while 886 ate ,more ...

  3. Colloids in the River Inn

    Science.gov (United States)

    Ueckert, Martina; Niessner, Reinhard; Baumann, Thomas

    2015-04-01

    In the light of an increasing number of technical applications using nanoparticles and reports of adverse effects of engineered nanoparticles, research on the occurrence and stability of particles in all compartments has to be intensified. Colloids in river water represent the geologic setting, environmental conditions, and the anthropogenic use in its catchment. The river not only acts as a sink for nanoparticles but also as the source term due to exchange in the hyporheic zone and in bank filtration setups. The concentration, size distribution and elemental composition of particles in the River Inn were studied from the source in the Swiss Alps to the river mouth at Passau from 2008 to 2014. Samples were collected after each tributary from a sub-catchment and filtered on site using a new filtration device for gentle filtration. The elemental composition was determined after acid digestion with ICP/MS. SEM/EDX analysis provided morphological and elemental information for single particles. A complementary chemical analysis of the river water was performed to assess the geochemical stability of individual particles. As presented at EGU 2014, particles in the upper, rural parts mainly reveal changes in the geological setting of the tributary catchments. Not unexpectedly, particles originating from crystalline rocks, were more stable than particles originating from calcareous rocks. Anthropogenic and industrial influences increase in the lower parts. This went together with a change of the size distribution, an increase of the number of organic particles, and a decrease of the microfauna. Interestingly, specific leisure activities in a sub-catchment, like extensive downhill skiing, manifest itself in the particle composition. This general setting was validated in last year's sampling campaigns. An interesting change in on site parameters and hydrochemical composition was seen during all sampling campaigns at an inflow from the valley Kaunertal, Austria. Therefore

  4. MICROPHYTOBENTHOS IN THE SUTLA RIVER

    Directory of Open Access Journals (Sweden)

    Marija Tomec

    2009-10-01

    Full Text Available The Sutla river is a river along Croatian/Slovenian border. Its length is about 91 km, out of which 89 km in Croatia. Microphytobenthos investigations have been performed at six locations along the Sutla river on Croatian territory. Samples were collected from specific areas of characteristic habitats. Beside sample collection, basic physico–chemical parameters were measured: water temperature, pH values and quantity of water dissolved oxygen. Water temperature changed depending on air temperature and the depth of the river, ranging from 5.1ºC to 6.3ºC. pH values were between 7.77 and 8.14, and dissolved oxygen concentrations (mg/L O2 at the six locations ranged between 8.6 mg/L and 14.9 mg/L. Quantitative microphytobenthos composition comprised 87 microphythic species belonging to the systematic groups of Bacteriophyta, Cyanobacteria and Chrysophyta (Bacillariophyceae and Xanthophyceae. The most numerous group were the diatoms or Bacillariophyceae (76 species or 88.3%, with dominance of the species of the genera Achnanthes, Cocconeis, Cymbella, Gomphonema, Navicula, Nitzschia and Surirella. The group Cyanobacteria was represented with relatively small number of species (9 species or 10%, with the dominance of filamentous algae belonging to the genus Phormidium. From the total number of the determined microphytobenthic species, 73 species or 84% were indicators of saprobity. Most of them were beta–mezosaprobic indicators. Based on the indicator values of determined microphytobenthic species at six investigated locations, P–B saprobity index was in the range from 1.8 to 2.0. These values suggested that the water at the investigated part of the Sutla river belonged to the second class of Croatian Water Quality Directive.

  5. Health evaluation indicator system for urban landscape rivers, case study of the Bailianjing River in Shanghai

    Science.gov (United States)

    Wang, Juan; Wang, Yue; Yang, Haizhen; Lu, Zhibo; Xu, Xiaotian

    2010-11-01

    The River Bailianjing is an iconic landscape feature known to all residents in Pudong area and running through the Shanghai Expo 2010 Park. The river and its basin was a complex living ecosystem which supports a unique variety of flora and fauna several decades ago. However, as a result of unsuccessful pollution source control, sewage and first flow of the storm water is directly coming into the river in some catchment. The water quality of the river is seriously organically polluted now. The typical organic pollutants are COD, NH3-N, TN and TP, which cause the extinction of the water plants and aquatic. Furthermore, the artificial hard river banks isolate the river course and the land, which damaged the whole ecological system totally. The nature of the River Bailianjing and its history has resulted in many government departments and authorities and non government organizations having jurisdiction and/or an interest in the river's management. As a new tool to improve river management, the river health assessment has become the major focus of ecological and environmental science. Consequently, research on river health evaluation and its development on river management are of great theoretical and practical significance. In order to evaluate the healthy status of the River Bailianjing and prepare comprehensive scientific background data for the integrated river ecological rehabilitation planning, the health evaluation indicator system for River Bailianjing is brought forward. The indicator system has three levels: the first is target layer; the second is criteria layer, including five fields: water quality characteristics, hydrology characteristics, river morphology, biological characteristics and river scenic beauty; the third is an index layer, a total of 15 specific indicators included. Fuzzy AHP method is used to evaluate the target river's health status, and five grades are set up to describe it: healthy, sub health, marginal, unhealthy and pathological. The

  6. Trace Elements in River Waters

    Science.gov (United States)

    Gaillardet, J.; Viers, J.; Dupré, B.

    2003-12-01

    Trace elements are characterized by concentrations lower than 1 mg L-1 in natural waters. This means that trace elements are not considered when "total dissolved solids" are calculated in rivers, lakes, or groundwaters, because their combined mass is not significant compared to the sum of Na+, K+, Ca2+, Mg2+, H4SiO4, HCO3-, CO32-, SO42-, Cl-, and NO3-. Therefore, most of the elements, except about ten of them, occur at trace levels in natural waters. Being trace elements in natural waters does not necessarily qualify them as trace elements in rocks. For example, aluminum, iron, and titanium are major elements in rocks, but they occur as trace elements in waters, due to their low mobility at the Earth's surface. Conversely, trace elements in rocks such as chlorine and carbon are major elements in waters.The geochemistry of trace elements in river waters, like that of groundwater and seawater, is receiving increasing attention. This growing interest is clearly triggered by the technical advances made in the determination of concentrations at lower levels in water. In particular, the development of inductively coupled plasma mass spectrometry (ICP-MS) has considerably improved our knowledge of trace-element levels in waters since the early 1990s. ICP-MS provides the capability of determining trace elements having isotopes of interest for geochemical dating or tracing, even where their dissolved concentrations are extremely low.The determination of trace elements in natural waters is motivated by a number of issues. Although rare, trace elements in natural systems can play a major role in hydrosystems. This is particularly evident for toxic elements such as aluminum, whose concentrations are related to the abundance of fish in rivers. Many trace elements have been exploited from natural accumulation sites and used over thousands of years by human activities. Trace elements are therefore highly sensitive indexes of human impact from local to global scale. Pollution

  7. Maple River Subbasin, Red River of the North Reconnaissance Report.

    Science.gov (United States)

    1980-12-01

    officials report no anticipated problems with their water supply. Erosion Problems Wind erosion is prevalent over most of the subbasin. Cultivated ...fully investigated. Wastewater Management The Upper Mississippi River Basin Commission (1977) reported high fecal coliform counts and a fecal coliform ...of the subbasin’s land area is under cultivation , and another 6.6 percent is devoted to pasture. The major crops grown in the subbasin are

  8. Isotopic geochemistry of Panama rivers

    Science.gov (United States)

    Harmon, Russell S.; Worner, Gerhard; Pribil, Michael; Kern, Zoltan; Forizs, Istvan; Lyons, W. Berry; Gardner, Christopher B.; Goldsmith, Steven T.

    2015-01-01

    River water samples collected from 78 watersheds rivers along a 500-km transect across a Late Cretaceous-Tertiary andesitic volcanic arc terrane in west-central Panama provide a synoptic overview of riverine geochemistry, chemical denudation, and CO2 consumption in the tropics. D/H and 18O/16O relationships indicate that bedrock dissolution of andesitic arc crust in Panama is driven by water-rock interaction with meteoric precipitation as it passes through the critical zone, with no evidence of a geothermal or hydrothermal input. Sr-isotope relationships suggest a geochemical evolution for Panama riverine waters that involves mixing of bedrock pore water with water having 87Sr/86Sr ratios between 0.7037-0.7043 and relatively high Sr-contents with waters of low Sr content that enriched in radiogenic Sr that are diluted by infiltrating rainfall to variable extents.

  9. Resilience of river flow regimes.

    Science.gov (United States)

    Botter, Gianluca; Basso, Stefano; Rodriguez-Iturbe, Ignacio; Rinaldo, Andrea

    2013-08-06

    Landscape and climate alterations foreshadow global-scale shifts of river flow regimes. However, a theory that identifies the range of foreseen impacts on streamflows resulting from inhomogeneous forcings and sensitivity gradients across diverse regimes is lacking. Here, we derive a measurable index embedding climate and landscape attributes (the ratio of the mean interarrival of streamflow-producing rainfall events and the mean catchment response time) that discriminates erratic regimes with enhanced intraseasonal streamflow variability from persistent regimes endowed with regular flow patterns. Theoretical and empirical data show that erratic hydrological regimes typical of rivers with low mean discharges are resilient in that they hold a reduced sensitivity to climate fluctuations. The distinction between erratic and persistent regimes provides a robust framework for characterizing the hydrology of freshwater ecosystems and improving water management strategies in times of global change.

  10. A river runs through it

    OpenAIRE

    F P J G Lafeber

    2010-01-01

    A river runs through it is een waar gebeurd verhaal over twee jongens, Norman en Paul, die in het begin van de 20ste eeuw opgroeiden in landelijk Montana (Amerika). Norman is in zijn jeugd een gereserveerde persoonlijkheid, terwijl Paul een rebelse ondeugd is. Beiden hebben echter een grote liefde voor vliegvissen. Het verhaal, gedeeltelijk autobiografisch, is geschreven in 1976 door Norman Maclean1. Er is geen Nederlandse vertaling. Wel is het boek in 1992 verfilmd onder regie van Robert Red...

  11. River Ehen and tributaries SSSI

    OpenAIRE

    1998-01-01

    This is the River Ehen and Tributaries SSSI consultation Protocol for the Environment Agency with English Nature, produced in 1998. The Protocol is intended to provide for consistency of approach, to clarify responsibilities and help to streamline the statutory consultation and consenting procedures in which both organisations are involved. It provides guiding principles on the approach to management issues. Based on the operations likely to damage the special interest (OLDSI) which forms par...

  12. Saving the Mekong River Basin

    OpenAIRE

    Houba, Harold; Pham Do, Kim Hang; Zhu, Xueqin

    2011-01-01

    The Mekong River (MR) is shared by six countries: China, Myanmar, Thailand, Laos, Cambodia, and Vietnam. Over the years there have been both conflict and cooperation on managing the water resources to meet population growth, climate change and the desire for economic development. Currently, the MR Committee (MRC) has weak policy instruments. This paper exploits an axiomatic bargaining approach to examine how China and the MRC might negotiate effective joint management. We investigate what wel...

  13. A Family By Yellow River

    OpenAIRE

    China Central Television (CCTV)

    2005-01-01

    A 63 minutes film produced by CCTV. It is only for education and non-commercial purpose. With thanks to Documentary Research Committee, of the Chinese Broadcasting and Television Academy. This filmed 5 years' record of a small village community, namely Lijiashan (Li's Mountains) of Qikou, Shanxi Province, might serve as an illustration for a profoundly changing rural China. A town in the valley of the Yellow River, Qikou lies culturally in the heartland of the vast yellowish land. It used ...

  14. Resilience of river flow regimes

    OpenAIRE

    Botter, G.; Basso, S.; Rodriguez-Iturbe, I.; Rinaldo, A.

    2013-01-01

    Landscape and climate alterations foreshadow global-scale shifts of river flow regimes. However, a theory that identifies the range of foreseen impacts on streamflows resulting from inhomogeneous forcings and sensitivity gradients across diverse regimes is lacking. Here, we derive a measurable index embedding climate and landscape attributes (the ratio of the mean interarrival of streamflow-producing rainfall events and the mean catchment response time) that discriminates erratic regimes with...

  15. Floquet theory of river ecomorphodynamics

    Science.gov (United States)

    Bertagni, Matteo; Perona, Paolo; Camporeale, Carlo

    2017-04-01

    Most of world population lives close and depends on freshwaters and related ecosystems. As dramatic consequence, 48% of all rivers worldwide are hydrologically altered. Although mankind lives by and controls river systems since millennia, a complete physically-based understanding of the links among the various processes involved still remains elusive. Three fundamental aspects control the physical state of natural rivers: flow stochasticity, sediment transport and vegetation dynamics. The present work tries to shed light on the bonds among these processes, following a temporal flow for the river dynamics. During a particularly extreme flood event any previous ecomorphological pattern is erased by the flow. However, sediment transport triggers the formation of migrating bedforms, called free bars. Through a nonlinear analysis, with center manifold projection, a long analytical expression is obtained for the bars amplitude, thus completely defining bars geometry in the parameters space. Once the formative event is extinguished, the flow rate decreases and the recently formed bars can partially emerge from water. At this point vegetation develops over the bare bars depending on flow stochasticity. As a realistic model for the flow stochasticity the compound Poisson process is considered. However, in order to make the computation analytically feasible, the stochastic time series for the discharge is replaced with an equivalent periodic one, obtained as a sequence of a typical average event of the stochastic series. In this manner, the new periodic streamflow signal, preserves the same statistical properties of its stochastic correspondent. The periodic equation for the vegetation dynamics can thus be spatially solved through Floquet theory, gaining which portion of the bar is asymptotically colonised by vegetation. In conclusion, this is the first theoretical work linking the trend of the vegetated area with the flow parameters, and confirming that high flow

  16. Raft River geoscience case study

    Energy Technology Data Exchange (ETDEWEB)

    Dolenc, M.R.; Hull, L.C.; Mizell, S.A.; Russell, B.F.; Skiba, P.A.; Strawn, J.A.; Tullis, J.A.

    1981-11-01

    The Raft River Geothermal Site has been evaluated over the past eight years by the United States Geological Survey and the Idaho National Engineering Laboratory as a moderate-temperature geothermal resource. The geoscience data gathered in the drilling and testing of seven geothermal wells suggest that the Raft River thermal reservoir is: (a) produced from fractures found at the contact metamorphic zone, apparently the base of detached normal faulting from the Bridge and Horse Well Fault zones of the Jim Sage Mountains; (b) anisotropic, with the major axis of hydraulic conductivity coincident to the Bridge Fault Zone; (c) hydraulically connected to the shallow thermal fluid of the Crook and BLM wells based upon both geochemistry and pressure response; (d) controlled by a mixture of diluted meteoric water recharging from the northwest and a saline sodium chloride water entering from the southwest. Although the hydrogeologic environment of the Raft River geothermal area is very complex and unique, it is typical of many Basin and Range systems.

  17. How do atmospheric rivers form?

    Science.gov (United States)

    Dacre, Helen

    2015-04-01

    The term atmospheric river is used to describe corridors of strong water vapor transport in the troposphere. Filaments of enhanced water vapor, commonly observed in satellite imagery extending from the subtropics to the extratropics, are routinely used as a proxy for identifying these regions of strong water vapor transport. The precipitation associated with these filaments of enhanced water vapor can lead to high impact flooding events. However, there remains some debate as to how these filaments form. In this study we analyse the transport of water vapor within a climatology of wintertime North Atlantic extratropical cyclones. Results show that atmospheric rivers are formed by the cold front which sweeps up water vapor in the warm sector as it catches up with the warm front. This causes a narrow band of high water vapor content to form ahead of the cold front at the base of the warm conveyor belt airflow. Thus, water vapor in the cyclone's warm sector, and not long-distance transport of water vapor from the subtropics, is responsible for the generation of filaments of high water vapor content. A continuous cycle of evaporation and moisture convergence within the cyclone replenishes water vapor lost via precipitation. Thus, rather than representing a direct and continuous feed of moist air from the subtropics into the centre of a cyclone (as suggested by the term atmospheric river), these filaments are, in-fact, the result of water vapor exported from the cyclone and thus they represent the footprints left behind as cyclones travel polewards from subtropics.

  18. THE IMPACT OF URBAN RIVER VALLEY LAND USE AND MORPHOLOGICAL CONDITION FOR RIVER VEGETATION IN RIVER BED

    Directory of Open Access Journals (Sweden)

    Adam Marek Hamerla

    2016-09-01

    Full Text Available This paper is focused on the results of research about the relationship between hydromorphological condition and share of plants in river bed. Assessment, made in urbanized and heavy industry part of Upper Silesia, provide proof of strong relation between land use, land cover in river valley and type of river vegetation. Moreover, the relationship between hydromorphological indicators and groups of plants was defined.

  19. The Upper Mississippi River System—Topobathy

    Science.gov (United States)

    Stone, Jayme M.; Hanson, Jenny L.; Sattler, Stephanie R.

    2017-03-23

    The Upper Mississippi River System (UMRS), the navigable part of the Upper Mississippi and Illinois Rivers, is a diverse ecosystem that contains river channels, tributaries, shallow-water wetlands, backwater lakes, and flood-plain forests. Approximately 10,000 years of geologic and hydrographic history exist within the UMRS. Because it maintains crucial wildlife and fish habitats, the dynamic ecosystems of the Upper Mississippi River Basin and its tributaries are contingent on the adjacent flood plains and water-level fluctuations of the Mississippi River. Separate data for flood-plain elevation (lidar) and riverbed elevation (bathymetry) were collected on the UMRS by the U.S. Army Corps of Engineers’ (USACE) Upper Mississippi River Restoration (UMRR) Program. Using the two elevation datasets, the U.S. Geological Survey (USGS) Upper Midwest Environmental Sciences Center (UMESC) developed a systemic topobathy dataset.

  20. Rare earth elements in river waters

    Science.gov (United States)

    Goldstein, Steven J.; Jacobsen, Stein B.

    1988-01-01

    To characterize the input to the oceans of rare earth elements (REE) in the dissolved and the suspended loads of rivers, the REE concentrations were measured in samples of Amazon, Indus, Mississippi, Murray-Darling, and Ohio rivers and in samples of smaller rivers that had more distinct drainage basin lithology and water chemistry. It was found that, in the suspended loads of small rivers, the REE pattern was dependent on drainage basin geology, whereas the suspended loads in major rivers had relatively uniform REE patterns and were heavy-REE depleted relative to the North American Shale composite (NASC). The dissolved loads in the five major rivers had marked relative heavy-REE enrichments, relative to the NASC and the suspended material, with the (La/Yb)N ratio of about 0.4 (as compared with the ratio of about 1.9 in suspended loads).

  1. 1890's Land Cover/Use - Mississippi River Commission Surveys, Open River 2

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — In the late 1880's and early 1900's the Mississippi River Commission (MRC) conducted an extensive high-resolution survey of the Mississippi River from Cairo,...

  2. 1890's Land Cover/Use - Mississippi River Commission Surveys, Open River 1

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — In the late 1880's and early 1900's the Mississippi River Commission (MRC) conducted an extensive high-resolution survey of the Mississippi River from Cairo,...

  3. New River Dam Foundation Report. Gila River Basin: Phoenix, Arizona and Vicinity (Including New River).

    Science.gov (United States)

    1985-10-01

    further downstream before merging with the Agua Fria River. 6 Site Geology 2.08 The geological formations present within the project area consist...channel and tributary wash deposits. The older Quaternary alluvium also includes the usually thin spotty veneer of residual soil and slope wash found on...that post magmatic hydrothermal alteration may have been caused by residual aqueous-gaseous fluids rising through the intergranular pore spaces in the

  4. Protecting and Enhancing River and Stream Continuity

    OpenAIRE

    Jackson, Scott D.; Bowden, Alison; Graber, Brian

    2007-01-01

    As long linear ecosystems, rivers and streams are particularly vulnerable to fragmentation. There is growing concern about the role of road crossings – and especially culverts – in altering habitats and disrupting river and stream continuity. The River and Stream Continuity Project began in the year 2000 with a startup grant from the Massachusetts Watershed Initiative. The University of Massachusetts took the lead in convening a group of people from a variety of agencies and organizations who...

  5. Ecological management of urban rivers in China

    Science.gov (United States)

    Zhang, Junhong; Hou, Xin; Xu, Yiping

    2017-03-01

    At present, China's urban river is widespread with serious pollution, poor water quality, poor water mobility and other issues. In this article, we analyzed the root causes of urban river water environment problems systematically, then puts forward the ways to solve the problems, which including implement the "river length system", strengthen the control of pollution sources, persist in ecological concepts, establish long-term mechanism and strengthen publicity and education.

  6. Monitoring river discharge with remotely sensed imagery using river island area as an indicator

    Science.gov (United States)

    Ling, Feng; Cai, Xiaobin; Li, Wenbo; Xiao, Fei; Li, Xiaodong; Du, Yun

    2012-01-01

    River discharge is an important parameter in understanding water cycles, and consistent long-term discharge records are necessary for related research. In practice, discharge records based on in situ measurement are often limited because of technological, economic, and institutional obstacles. Satellite remote sensing provides an attractive alternative way to measure river discharge by constructing an empirical rating curve between the parameter provided by remote sensing techniques and simultaneous ground discharge data. River width is a popular parameter for constructing the empirical curve, since change in river discharge can be represented by a change in river width. In some rectangular channels, however, river width does not change significantly with river discharge, so an alternative parameter is necessary. We analyze a novel technique using river island area as an indicator of discharge. A river island often has a flat terrain, and its area decreases with higher discharge. This technique is validated by three river islands in the Yangtze River in China. All 61 remotely sensed images acquired by the HuanJing (HJ) satellites from 2009 to 2010 were correlated with corresponding in situ discharge of the nearby Zhicheng hydrological station. The performance of fitted curves for inferring river discharge is validated using 36 HJ images taken in 2011, and the influence of remotely sensed imagery and river islands is discussed. All three river islands can be used as indicators of river discharge, although their performances are much different. For the river island with the best result, the mean accuracy of the estimates is less than 10% of the observed discharge, and all relative errors are within 20%, validating the effectiveness of the proposed method.

  7. Forms of Nutrients in Rivers Flowing into Lake Chaohu: A Comparison between Urban and Rural Rivers

    OpenAIRE

    Lei Zhang; Shiguang Shao; Cheng Liu; Tingting Xu; Chengxin Fan

    2015-01-01

    Nutrient inputs from rivers play an important role in lake eutrophication. To compare the forms characteristics of phosphorus (P) and nitrogen (N) in rivers flowing through rural and urban areas, water samples were collected seasonally from five urban rivers and six rural rivers flowing to Lake Chaohu, China. Higher total phosphorus (TP), particulate phosphorus (PP), soluble reactive phosphorus (SRP), and dissolved nonreactive phosphorus (DNP) concentrations and SRP/TP percentages were observ...

  8. Savannah River Laboratory monthly report, October 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. [comp.

    1991-12-31

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation, tritium facilities and production; separations operations; environmental concerns; and waste management. (FI)

  9. Savannah River Laboratory monthly report, October 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. (comp.)

    1991-01-01

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation, tritium facilities and production; separations operations; environmental concerns; and waste management. (FI)

  10. Savannah River Laboratory monthly report, September 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. [comp.

    1991-12-31

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation, tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

  11. Savannah River Laboratory monthly report, September 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. (comp.)

    1991-01-01

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation, tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

  12. The Columbia River System Inside Story

    Energy Technology Data Exchange (ETDEWEB)

    None

    2001-04-01

    The Columbia River is one of the greatest natural resources in the western United States. The river and its tributaries touch the lives of nearly every resident of the Pacific Northwest—from fostering world-famous Pacific salmon to supplying clean natural fuel for 50 to 65 percent of the region’s electrical generation. Since early in the 20th century, public and private agencies have labored to capture the benefits of this dynamic river. Today, dozens of major water resource projects throughout the region are fed by the waters of the Columbia Basin river system.

  13. Savannah River Laboratory monthly report, August 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. (comp.)

    1991-01-01

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation, tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

  14. Savannah River Laboratory monthly report, July 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. [comp.

    1991-12-31

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation; tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

  15. Savannah River Laboratory monthly report, August 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. [comp.

    1991-12-31

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation, tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

  16. Savannah River Laboratory monthly report, November 1991

    Energy Technology Data Exchange (ETDEWEB)

    Ferrell, J.M. [comp.

    1991-12-31

    This document details monthly activities at the Savannah River Laboratory. Topics addressed are reactor operation; tritium facilities and production; separation operations; environmental concerns; and waste management. (FI)

  17. Bathymetric surveys of the Neosho River, Spring River, and Elk River, northeastern Oklahoma and southwestern Missouri, 2016–17

    Science.gov (United States)

    Hunter, Shelby L.; Ashworth, Chad E.; Smith, S. Jerrod

    2017-09-26

    In February 2017, the Grand River Dam Authority filed to relicense the Pensacola Hydroelectric Project with the Federal Energy Regulatory Commission. The predominant feature of the Pensacola Hydroelectric Project is Pensacola Dam, which impounds Grand Lake O’ the Cherokees (locally called Grand Lake) in northeastern Oklahoma. Identification of information gaps and assessment of project effects on stakeholders are central aspects of the Federal Energy Regulatory Commission relicensing process. Some upstream stakeholders have expressed concerns about the dynamics of sedimentation and flood flows in the transition zone between major rivers and Grand Lake O’ the Cherokees. To relicense the Pensacola Hydroelectric Project with the Federal Energy Regulatory Commission, the hydraulic models for these rivers require high-resolution bathymetric data along the river channels. In support of the Federal Energy Regulatory Commission relicensing process, the U.S. Geological Survey, in cooperation with the Grand River Dam Authority, performed bathymetric surveys of (1) the Neosho River from the Oklahoma border to the U.S. Highway 60 bridge at Twin Bridges State Park, (2) the Spring River from the Oklahoma border to the U.S. Highway 60 bridge at Twin Bridges State Park, and (3) the Elk River from Noel, Missouri, to the Oklahoma State Highway 10 bridge near Grove, Oklahoma. The Neosho River and Spring River bathymetric surveys were performed from October 26 to December 14, 2016; the Elk River bathymetric survey was performed from February 27 to March 21, 2017. Only areas inundated during those periods were surveyed.The bathymetric surveys covered a total distance of about 76 river miles and a total area of about 5 square miles. Greater than 1.4 million bathymetric-survey data points were used in the computation and interpolation of bathymetric-survey digital elevation models and derived contours at 1-foot (ft) intervals. The minimum bathymetric-survey elevation of the Neosho

  18. Upstream control of river anastomosis by sediment overloading, upper Columbia River, British Columbia, Canada

    NARCIS (Netherlands)

    Makaske, Bart; Lavooi, Eva; de Haas, Tjalling; Kleinhans, Maarten G.; Smith, Derald G.

    2017-01-01

    Anastomosing rivers, systems of multiple interconnected channels that enclose floodbasins, constitute a major category of rivers for which various sedimentary facies models have been developed. While the sedimentary products of anastomosing rivers are relatively well-known, their genesis is still

  19. Upstream control of river anastomosis by sediment overloading, upper Columbia River, British Columbia, Canada.

    NARCIS (Netherlands)

    Makaske, A.; Lavooi, E.; Haas, de Tjalling; Kleinhans, M.G.; Smith, D.G.

    2017-01-01

    Anastomosing rivers, systems of multiple interconnected channels that enclose floodbasins, constitute a major category of rivers for which various sedimentary facies models have been developed. While the sedimentary products of anastomosing rivers are relatively well-known, their genesis is still

  20. River-tide dynamics : Exploration of nonstationary and nonlinear tidal behavior in the Yangtze River estuary

    NARCIS (Netherlands)

    Guo, L.; Van der Wegen, M.; Jay, D.A.; Matte, P.; Wang, Z.B.; Roelvink, J.A.; He, Q.

    2015-01-01

    River-tide dynamics remain poorly understood, in part because conventional harmonic analysis (HA) does not cope effectively with nonstationary signals. To explore nonstationary behavior of river tides and the modulation effects of river discharge, this work analyzes tidal signals in the Yangtze

  1. 76 FR 75543 - Missisquoi River Technologies; Missisquoi River Hydro LLC; Notice of Transfer of Exemption

    Science.gov (United States)

    2011-12-02

    ... Transfer of Exemption 1. By letter filed November 16, 2011, Missisquoi River Technologies informed the... issued June 29, 1989,\\1\\ has been transferred to Missisquoi River Hydro LLC. The project is located on the Missisquoi River in Orleans County, Vermont. The transfer of an exemption does not require...

  2. 78 FR 28492 - Special Local Regulation; Low Country Splash, Wando River, Cooper River, and Charleston Harbor...

    Science.gov (United States)

    2013-05-15

    ... of Proposed Rulemaking A. Regulatory History and Information On March 26, 2013, we published a notice... River, Cooper River, and Charleston Harbor in Charleston, SC. The race will consist of approximately 500 swimmers. The race will commence at Daniel Island Pier, transit south in the Wando River, crossing the...

  3. 76 FR 24914 - Digital River Education Services, Inc., a Division of Digital River, Inc., Including Workers...

    Science.gov (United States)

    2011-05-03

    ... Employment and Training Administration Digital River Education Services, Inc., a Division of Digital River... Marketing (JEM), Including On-Site Lease Workers From Serenity Staffing, Accountemps, Silicon Valley, and... Assistance on January 28, 2011, applicable to workers of Digital River Education Services, Inc., a division...

  4. River Platform for Monitoring Erosion (RIPLE) in mountainous rivers

    Science.gov (United States)

    Michielin, Yoann; Nord, Guillaume; Esteves, Michel; Geay, Thomas; Hauet, Alexandre

    2017-04-01

    The RIPLE platform has been developed to allow a continuous monitoring at high temporal frequency ( 10 min) of water and solid fluxes in mountainous rivers. The scientific context of this development is defined as follows: (i) the simultaneous measurements of water discharge, bedload, suspension load and river bed topography contribute to the establishment of comprehensive mass balance at the catchment scale; (ii) measurements of the physical properties of fine sediments (size, shape, composition) provide information on the spatial origin of sediments within the catchment, the conditions for erosion and sedimentation processes within the river and the potential to transport other substances such as nutrients, metals, microorganisms. For the design of the platform, priority has been given to non-intrusive instruments due to their robustness. The basic prototype of the platform integrates the following instruments: water level and surface velocity radars, turbidimeters, conductivity probe, hydrophone, cameras, automatic water sampler and depth sounder. Other instruments are progressively integrated, such as the SCAF (system characterizing the sediment's settling velocity), an acoustic Doppler profiler and a spectrophotometer. A wireless telecommunication has been set up to allow remote interactions with the platform and data transmission. The RIPLE platform has been designed to facilitate its use and maintenance: user interface allowing data monitoring and remote configuration, sending alerts (SMS, mail) according to programmed conditions, flexibility of on-site installation and energy autonomy allowing to easily move the platform from one site to another site. In September 2016, the RIPLE platform was installed on a bridge across the Romanche river at Bourg d'Oisans (45.1159 °N, 6.0135 °E) for a testing period. After a presentation of the architecture of the platform, the first results derived from in situ measurements are discussed: the intercomparison of surface

  5. Large River Monitoring Forum Fish Assemblage Database 2016

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Large River Monitoring Forum compiled fish assemblage data for five large rivers in the U.S. as a part of a coordinated effort to compare and contract river...

  6. River classification is important for reporting ecological status and ...

    African Journals Online (AJOL)

    River classification is important for reporting ecological status and for the general ecological management of river systems by partitioning natural variability. A priori river classification by abiotic variables and validation of classifications obtained.

  7. Consequence Analyses Following Potential Savannah River Site Hydrological Releases

    Energy Technology Data Exchange (ETDEWEB)

    Blanchard, A.

    1999-07-28

    Postulated accidental release of radiological material to surface water bodies on the Savannah River Site and the resulting downstream contamination of the Savannah River pose a potential threat to downstream river users.

  8. An Assessment of River Resources for Louisiana Coastal Land Preservation

    Science.gov (United States)

    2008-05-01

    35 Table 4.2: Listing of existing Mississippi River diversions below Natchez (from...600,000 cfs. 37 Table 4.2: Listing of existing Mississippi River diversions below Natchez (from Andrus (2007)). Diversion River Mile (above

  9. Flood of August 24–25, 2016, Upper Iowa River and Turkey River, northeastern Iowa

    Science.gov (United States)

    Linhart, S. Mike; O'Shea, Padraic S.

    2018-02-05

    Major flooding occurred August 24–25, 2016, in the Upper Iowa River Basin and Turkey River Basin in northeastern Iowa following severe thunderstorm activity over the region. About 8 inches of rain were recorded for the 24-hour period ending at 4 p.m., August 24, at Decorah, Iowa, and about 6 inches of rain were recorded for the 24-hour period ending at 7 a.m., August 24, at Cresco, Iowa, about 14 miles northwest of Spillville, Iowa. A maximum peak-of-record discharge of 38,000 cubic feet per second in the Upper Iowa River at streamgage 05388250 Upper Iowa River near Dorchester, Iowa, occurred on August 24, 2016, with an annual exceedance-probability range of 0.2–1 percent. High-water marks were measured at six locations along the Upper Iowa River between State Highway 26 near the mouth at the Mississippi River and State Highway 76 about 3.5 miles south of Dorchester, Iowa, a distance of 15 river miles. Along the profiled reach of the Turkey River, a maximum peak-of-record discharge of 15,300 cubic feet per second at streamgage 05411600 Turkey River at Spillville, Iowa, occurred on August 24, 2016, with an annual exceedance-probability range of 1–2 percent. A maximum peak discharge of 35,700 cubic feet per second occurred on August 25, 2016, along the profiled reach of the Turkey River at streamgage 05411850 Turkey River near Eldorado, Iowa, with an annual exceedance-probability range of 0.2–1 percent. High-water marks were measured at 11 locations along the Turkey River between County Road B64 in Elgin and 220th Street, located about 4.5 miles northwest of Spillville, Iowa, a distance of 58 river miles. The high-water marks were used to develop flood profiles for the Upper Iowa River and Turkey River.

  10. Nitrogen and phosphorus in the Upper Mississippi River: Transport, processing, and effects on the river ecosystem

    Science.gov (United States)

    Houser, J.N.; Richardson, W.B.

    2010-01-01

    Existing research on nutrients (nitrogen and phosphorus) in the Upper Mississippi River (UMR) can be organized into the following categories: (1) Long-term changes in nutrient concentrations and export, and their causes; (2) Nutrient cycling within the river; (3) Spatial and temporal patterns of river nutrient concentrations; (4) Effects of elevated nutrient concentrations on the river; and (5) Actions to reduce river nutrient concentrations and flux. Nutrient concentration and flux in the Mississippi River have increased substantially over the last century because of changes in land use, climate, hydrology, and river management and engineering. As in other large floodplain rivers, rates of processes that cycle nitrogen and phosphorus in the UMR exhibit pronounced spatial and temporal heterogeneity because of the complex morphology of the river. This spatial variability in nutrient processing creates clear spatial patterns in nutrient concentrations. For example, nitrate concentrations generally are much lower in off-channel areas than in the main channel. The specifics of in-river nutrient cycling and the effects of high rates of nutrient input on UMR have been less studied than the factors affecting nutrient input to the river and transport to the Gulf of Mexico, and important questions concerning nutrient cycling in the UMR remain. Eutrophication and resulting changes in river productivity have only recently been investigated the UMR. These recent studies indicate that the high nutrient concentrations in the river may affect community composition of aquatic vegetation (e. g., the abundance of filamentous algae and duckweeds), dissolved oxygen concentrations in off-channel areas, and the abundance of cyanobacteria. Actions to reduce nutrient input to the river include changes in land-use practices, wetland restoration, and hydrological modifications to the river. Evidence suggests that most of the above methods can contribute to reducing nutrient concentration in

  11. Coastal river plumes: Collisions and coalescence

    Science.gov (United States)

    Warrick, Jonathan A.; Farnsworth, Katherine L.

    2017-02-01

    Plumes of buoyant river water spread in the ocean from river mouths, and these plumes influence water quality, sediment dispersal, primary productivity, and circulation along the world's coasts. Most investigations of river plumes have focused on large rivers in a coastal region, for which the physical spreading of the plume is assumed to be independent from the influence of other buoyant plumes. Here we provide new understanding of the spreading patterns of multiple plumes interacting along simplified coastal settings by investigating: (i) the relative likelihood of plume-to-plume interactions at different settings using geophysical scaling, (ii) the diversity of plume frontal collision types and the effects of these collisions on spreading patterns of plume waters using a two-dimensional hydrodynamic model, and (iii) the fundamental differences in plume spreading patterns between coasts with single and multiple rivers using a three-dimensional hydrodynamic model. Geophysical scaling suggests that coastal margins with numerous small rivers (watershed areas 100,000 km2). When two plume fronts meet, several types of collision attributes were found, including refection, subduction and occlusion. We found that the relative differences in pre-collision plume densities and thicknesses strongly influenced the resulting collision types. The three-dimensional spreading of buoyant plumes was found to be influenced by the presence of additional rivers for all modeled scenarios, including those with and without Coriolis and wind. Combined, these results suggest that plume-to-plume interactions are common phenomena for coastal regions offshore of the world's smaller rivers and for coastal settings with multiple river mouths in close proximity, and that the spreading and fate of river waters in these settings will be strongly influenced by these interactions. We conclude that new investigations are needed to characterize how plumes interact offshore of river mouths to better

  12. Sediment fluxes in transboundary Selenga river basin

    Science.gov (United States)

    Belozerova, Ekaterina

    2013-04-01

    Gathering reliable information on transboundary river systems remains a crucial task for international water management and environmental pollution control. Countries located in the lower parts of the river basins depend on water use and management strategies in adjacent upstream countries. One important issue in this context is sediment transport and associated contaminant fluxes across the state borders. The mass flows of dissolved ions, biogens, heavy metal concentrations, as far as suspended sediment concentration (SSC, mg/l) along upper Selenga river and its tributaries based on the literature review and results of field campaigns 2011-2012 were estimated. Based on the water discharges measurements Q, suspended load WR (t/day) and dissolved loads WL were calculated. In the Selenga basin the minimal WR (1,34-3,74 t/day) were found at small rivers. Maximal sediment loads (WR = 15 000 t/day) were found at the upper Orkhon river during flood event. The downstream point (Mongolia-Russia border) was characterized 2 220 t/day in 2011. Generally the prevalence of the accumulation is found through calculating sediment budget for all rivers (ΔW = WR (downstream) - WR (upstream) mining and pastures) increases the portion of clay particles in total sediment load (e.g. at the downstream point of most polluted Orkhon river it reached 207,8 t/day). The existed estimates are compared with distribution of the main matter sources within basin: mining and industry, river-bank erosion and slope wash. The heaviest increase of suspended and dissolved matter transport is indicated along Tuul-Orkhon river system (right tributary of the Selenga river where Mongolia capital Ulaanbaator, gold mine Zaamar and few other mines). The results provide evidence on a connection between increased heavy metal concentrations in water-sediment systems of transboundary rivers and pollutant source zones at industrial and mining centers, both as in-channel erosion and land use.

  13. River water quality modelling: II

    DEFF Research Database (Denmark)

    Shanahan, P.; Henze, Mogens; Koncsos, L.

    1998-01-01

    The U.S. EPA QUAL2E model is currently the standard for river water quality modelling. While QUAL2E is adequate for the regulatory situation for which it was developed (the U.S. wasteload allocation process), there is a need for a more comprehensive framework for research and teaching. Moreover......, and to achieve robust model calibration. Mass balance problems arise from failure to account for mass in the sediment as well as in the water column and due to the fundamental imprecision of BOD as a state variable. (C) 1998 IAWQ Published by Elsevier Science Ltd. All rights reserved....

  14. Fish diseases in coastal rivers

    Energy Technology Data Exchange (ETDEWEB)

    Moeller, H.

    1984-10-01

    Fish diseases have been used as pollution indicators in surface water for about 15 years. The complex interdependences between pathogens, fish, and a multitude of environmental parameters make data evaluation difficult and may lead to misinterpretations. The effects of the natural environment are found to be more important than pollutant effects. To give an example: In a number of fish species, disease rates were highest not in the strongly polluted stretch of river near Hamburg but in the estuarine region where pollutant concentrations are comparatively low but salt content fluctuations are high.

  15. Hydrogeological investigations of river bed clogging at a river bank filtration site along the River Warta, Poland

    Directory of Open Access Journals (Sweden)

    Przybyłek Jan

    2017-12-01

    Full Text Available River bank filtration (RBF is a system that enriches groundwater resources by induced infiltration of river water to an aquifer. Problematic during operation of RBF systems is the deterioration of infiltration effectiveness caused by river bed clogging. This situation was observed in the Krajkowo well field which supplies fresh water to the city of Poznań (Poland during and after the long hydrological drought between the years 1989 and 1992. The present note discusses results of specific hydrogeological research which included drilling of a net of boreholes to a depth of 10 m below river bottom (for sediment sampling as well as for hydrogeological measurements, analyses of grain size distribution and relative density studies. The results obtained have allowed the recognition of the origin of the clogging processes, as well as the documentation of the clogged parts of the river bottom designated for unclogging activities.

  16. Hydrogeological investigations of river bed clogging at a river bank filtration site along the River Warta, Poland

    Science.gov (United States)

    Przybyłek, Jan; Dragon, Krzysztof; Kaczmarek, Piotr Michał Jan

    2017-12-01

    River bank filtration (RBF) is a system that enriches groundwater resources by induced infiltration of river water to an aquifer. Problematic during operation of RBF systems is the deterioration of infiltration effectiveness caused by river bed clogging. This situation was observed in the Krajkowo well field which supplies fresh water to the city of Poznań (Poland) during and after the long hydrological drought between the years 1989 and 1992. The present note discusses results of specific hydrogeological research which included drilling of a net of boreholes to a depth of 10 m below river bottom (for sediment sampling as well as for hydrogeological measurements), analyses of grain size distribution and relative density studies. The results obtained have allowed the recognition of the origin of the clogging processes, as well as the documentation of the clogged parts of the river bottom designated for unclogging activities.

  17. River geomorphology and fish barriers affect on spatial and temporal patterns of fish assemblages in the Niobrara River, Nebraska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Niobrara River in northern Nebraska traverses the heart of the Great Plains with portions of the river protected under the National Wild and Scenic River system...

  18. The Vaal river catchment: Problems and research needs

    CSIR Research Space (South Africa)

    Braune, E

    1987-01-01

    Full Text Available . THE VAAL RIVER SYSTEM The V a a l River r i s e s on the western slopes of the Drakensberg escarpment and flows about 900 km west-south-west across the i n t e r io r plateau t o join the Orange River near Douglas (Figure 11. The major t r i b u t a... Allemanskraal Erf en is Bloemhof Vaalharts Spitskop Rustfontein Krugersdrif t Tierpoort Kalkfontein Douglas Weir V a a l River Nuwe jaarssprui t Vaal River Vaal River Mooi Renoster Sand Vet V a a l River Vaal River Harts Modder Modder...

  19. Balancing hydropower production and river bed incision in operating a run-of-river hydropower scheme along the River Po

    Science.gov (United States)

    Denaro, Simona; Dinh, Quang; Bizzi, Simone; Bernardi, Dario; Pavan, Sara; Castelletti, Andrea; Schippa, Leonardo; Soncini-Sessa, Rodolfo

    2013-04-01

    Water management through dams and reservoirs is worldwide necessary to support key human-related activities ranging from hydropower production to water allocation, and flood risk mitigation. Reservoir operations are commonly planned in order to maximize these objectives. However reservoirs strongly influence river geomorphic processes causing sediment deficit downstream, altering the flow regime, leading, often, to process of river bed incision: for instance the variations of river cross sections over few years can notably affect hydropower production, flood mitigation, water supply strategies and eco-hydrological processes of the freshwater ecosystem. The river Po (a major Italian river) has experienced severe bed incision in the last decades. For this reason infrastructure stability has been negatively affected, and capacity to derive water decreased, navigation, fishing and tourism are suffering economic damages, not to mention the impact on the environment. Our case study analyzes the management of Isola Serafini hydropower plant located on the main Po river course. The plant has a major impact to the geomorphic river processes downstream, affecting sediment supply, connectivity (stopping sediment upstream the dam) and transport capacity (altering the flow regime). Current operation policy aims at maximizing hydropower production neglecting the effects in term of geomorphic processes. A new improved policy should also consider controlling downstream river bed incision. The aim of this research is to find suitable modeling framework to identify an operating policy for Isola Serafini reservoir able to provide an optimal trade-off between these two conflicting objectives: hydropower production and river bed incision downstream. A multi-objective simulation-based optimization framework is adopted. The operating policy is parameterized as a piecewise linear function and the parameters optimized using an interactive response surface approach. Global and local

  20. Compromised Rivers: Understanding Historical Human Impacts on Rivers in the Context of Restoration

    Directory of Open Access Journals (Sweden)

    Ellen Wohl

    2005-12-01

    Full Text Available A river that preserves a simplified and attractive form may nevertheless have lost function. Loss of function in these rivers can occur because hydrologic and geomorphic processes no longer create and maintain the habitat and natural disturbance regimes necessary for ecosystem integrity. Recognition of compromised river function is particularly important in the context of river restoration, in which the public perception of a river's condition often drives the decision to undertake restoration as well as the decision about what type of restoration should be attempted. Determining the degree to which a river has been altered from its reference condition requires a knowledge of historical land use and the associated effects on rivers. Rivers of the Front Range of the Colorado Rocky Mountains in the United States are used to illustrate how historical land uses such as beaver trapping, placer mining, tie drives, flow regulation, and the construction of transportation corridors continue to affect contemporary river characteristics. Ignorance of regional land use and river history can lead to restoration that sets unrealistic goals because it is based on incorrect assumptions about a river's reference condition or about the influence of persistent land-use effects.

  1. Environmental flow for Monsoon Rivers in India: The Yamuna River as a case study

    CERN Document Server

    Soni, Vikram; Singh, Diwan

    2013-01-01

    We consider the flows of Monsoon Rivers in India that will permit the river to perform all its natural functions. About 80% of the total flow for Indian rivers is during the monsoon and the remaining 20% is during the non monsoon period. By carrying out a case study of the river Yamuna in Delhi we find that at least 50% of the virgin monsoon (July to September) flow is required for the transport of the full spectrum of soil particles in the river sediment. A similar flow is needed for adequate recharge of the floodplain aquifers along river. For the non monsoon period (October to June) about 60% of the virgin flow is necessary to avoid the growth of still water algae and to support river biodiversity.

  2. River meander modeling of the Wabash River near the Interstate 64 Bridge near Grayville, Illinois

    Science.gov (United States)

    Lant, Jeremiah G.; Boldt, Justin A.

    2018-01-16

    Natural river channels continually evolve and change shape over time. As a result, channel evolution or migration can cause problems for bridge structures that are fixed in the flood plain. A once-stable bridge structure that was uninfluenced by a river’s shape could be encroached upon by a migrating river channel. The potential effect of the actively meandering Wabash River on the Interstate 64 Bridge at the border with Indiana near Grayville, Illinois, was studied using a river migration model called RVR Meander. RVR Meander is a toolbox that can be used to model river channel meander migration with physically based bank erosion methods. This study assesses the Wabash River meandering processes through predictive modeling of natural meandering over the next 100 years, climate change effects through increased river flows, and bank protection measures near the Interstate 64 Bridge.

  3. Industrial pollution and the management of river water quality: a model of Kelani River, Sri Lanka.

    Science.gov (United States)

    Gunawardena, Asha; Wijeratne, E M S; White, Ben; Hailu, Atakelty; Pandit, Ram

    2017-08-19

    Water quality of the Kelani River has become a critical issue in Sri Lanka due to the high cost of maintaining drinking water standards and the market and non-market costs of deteriorating river ecosystem services. By integrating a catchment model with a river model of water quality, we developed a method to estimate the effect of pollution sources on ambient water quality. Using integrated model simulations, we estimate (1) the relative contribution from point (industrial and domestic) and non-point sources (river catchment) to river water quality and (2) pollutant transfer coefficients for zones along the lower section of the river. Transfer coefficients provide the basis for policy analyses in relation to the location of new industries and the setting of priorities for industrial pollution control. They also offer valuable information to design socially optimal economic policy to manage industrialized river catchments.

  4. Modelling morphodynamic evolution of river dunes

    NARCIS (Netherlands)

    Paarlberg, Andries; Dohmen-Janssen, Catarine M.; Hulscher, Suzanne J.M.H.; van den Berg, J.; Termes, A.P.P.; Ferreira, Rui M.L.

    2006-01-01

    River dunes influence the hydraulic roughness and water levels in rivers. Especially during floods the interplay between dunes and the flow field could become significant. Therefore, it is desired to forecast the dimensions of dunes during such extreme and unsteady flood events. At present it is not

  5. 33 CFR 117.263 - Banana River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Banana River. 117.263 Section 117.263 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.263 Banana River. (a) The draw of the Mathers (SR...

  6. Savannah River Site Environmental Report for 1998

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M

    1999-06-09

    The mission at the Savannah River Site (SRS) is focused primarily on support of the national defense, nonproliferation, and environmental cleanup. SRS-through its prime operating contractor, Westinghouse Savannah River Company-continues to maintain a comprehensive environmental monitoring program.

  7. Experiments on sediment pulses in mountain rivers

    Science.gov (United States)

    Y. Cui; T. E. Lisle; J. E. Pizzuto; G. Parker

    1998-01-01

    Pulses of sediment can be introduced into mountain rivers from such mechanisms as debris flows, landslides and fans at tributary confluences. These processes can be natural or associated with the activities of humans, as in the case of a pulse created by sediment derived from timber harvest or the removal of a dam. How does the river digest these pulses?

  8. 33 CFR 117.971 - Neches River.

    Science.gov (United States)

    2010-07-01

    ... OPERATION REGULATIONS Specific Requirements Texas § 117.971 Neches River. (a) The draw of the Kansas City... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Neches River. 117.971 Section 117..., providing 13 feet of vertical clearance above mean high tide. This bridge will open on signal. (1) Mariners...

  9. 33 CFR 117.989 - Trinity River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Trinity River. 117.989 Section 117.989 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Texas § 117.989 Trinity River. The draws of the Union...

  10. River System Behaviour Effects on Flood Risk

    NARCIS (Netherlands)

    Schweckendiek, T.; Vrouwenvelder, A.C.W.M.; Van Mierlo, M.C.L.M.; Calle, E.O.F.; Courage, W.M.G.

    2008-01-01

    A risk-based safety approach is indispensable to support decision-making on flood protection strategies and measures. Hitherto the effects of river system behaviour on flood risk have usually been neglected. River system behaviour refers to the fact that the flood risk (or safety) of a particular

  11. Advances in understanding river-groundwater interactions

    Science.gov (United States)

    Brunner, Philip; Therrien, René; Renard, Philippe; Simmons, Craig T.; Franssen, Harrie-Jan Hendricks

    2017-09-01

    River-groundwater interactions are at the core of a wide range of major contemporary challenges, including the provision of high-quality drinking water in sufficient quantities, the loss of biodiversity in river ecosystems, or the management of environmental flow regimes. This paper reviews state of the art approaches in characterizing and modeling river and groundwater interactions. Our review covers a wide range of approaches, including remote sensing to characterize the streambed, emerging methods to measure exchange fluxes between rivers and groundwater, and developments in several disciplines relevant to the river-groundwater interface. We discuss approaches for automated calibration, and real-time modeling, which improve the simulation and understanding of river-groundwater interactions. Although the integration of these various approaches and disciplines is advancing, major research gaps remain to be filled to allow more complete and quantitative integration across disciplines. New possibilities for generating realistic distributions of streambed properties, in combination with more data and novel data types, have great potential to improve our understanding and predictive capabilities for river-groundwater systems, especially in combination with the integrated simulation of the river and groundwater flow as well as calibration methods. Understanding the implications of different data types and resolution, the development of highly instrumented field sites, ongoing model development, and the ultimate integration of models and data are important future research areas. These developments are required to expand our current understanding to do justice to the complexity of natural systems.

  12. A concise history of Dutch river floods

    NARCIS (Netherlands)

    Tol, R.S.J.; Langen, A.

    2000-01-01

    Based on a brief account of 1,000 years of river floods and flood management in the Dutch Rhine delta, it is argued that vulnerability to river floods depends on the complex interaction of economics, institutions, politics and, to a limited extent, climate. Response functions and thresholds for

  13. Thinking big: linking rivers to landscapes

    Science.gov (United States)

    Joan O’Callaghan; Ashley E. Steel; Kelly M. Burnett

    2012-01-01

    Exploring relationships between landscape characteristics and rivers is an emerging field, enabled by the proliferation of satellite date, advances in statistical analysis, and increased emphasis on large-scale monitoring. Landscapes features such as road networks, underlying geology, and human developments, determine the characteristics of the rivers flowing through...

  14. 33 CFR 117.385 - Snake River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Snake River. 117.385 Section 117.385 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Idaho § 117.385 Snake River. The drawspan of the U.S. 12 bridge...

  15. Gila River Basin Native Fishes Conservation Program

    Science.gov (United States)

    Doug Duncan; Robert W. Clarkson

    2013-01-01

    The Gila River Basin Native Fishes Conservation Program was established to conserve native fishes and manage against nonnative fishes in response to several Endangered Species Act biological opinions between the Bureau of Reclamation and the U.S. Fish and Wildlife Service on Central Arizona Project (CAP) water transfers to the Gila River basin. Populations of some Gila...

  16. Volatilization of Benzene in a River

    Directory of Open Access Journals (Sweden)

    Eric Dunlop

    2013-01-01

    Full Text Available Benzene is a volatile organic compound: when it contaminates a river, some of the substance will evaporate as it flows through. We examine the volumetric flow rate to find how volatilization affects the concentration levels of benzene as the substance flows through several consecutive sections of a river, using a specific example to illustrate the general method.

  17. The Nile River and the Riparian States

    African Journals Online (AJOL)

    An acceptable legal regime to manage the Nile River and its drainage system for equitable intra-and inter- state econo-political and socio-cultural utilisation remains a major challenge. For many decades after independence, particularly since the 1980s, the Nile River riparian states have engaged in numerous bilateral and ...

  18. 33 CFR 117.803 - Niagara River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Niagara River. 117.803 Section 117.803 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements New York § 117.803 Niagara River. The draw of the...

  19. Implementing Integrated River Basin Management in China

    NARCIS (Netherlands)

    Boekhorst, D.G.J. te; Smits, A.J.M.; Yu, X.; Lifeng, L.; Lei, G.; Zhang, C.

    2010-01-01

    This paper examines the role of the World Wildlife Fund for Nature China as policy entrepreneur in China. It illustrates the ways in which the World Wildlife Fund for Nature is active in promoting integrated river basin management in the Yangtze River basin and how the efforts at basin level are

  20. 33 CFR 117.417 - Ohio River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Ohio River. 117.417 Section 117.417 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Kentucky § 117.417 Ohio River. The draw of the Southern Railway...

  1. Vocal behaviour of Orange River Francolin Scleroptila ...

    African Journals Online (AJOL)

    ... the size of the population. A 'ke-ri ke-chi' playback call enticed three different calls from Orange River Francolins that can be used for management purposes, including the 'ke-ri ke-chi', cacophony and female calls. These three calls can be used to locate Orange River Francolins, determine dispersion, habitat preferences, ...

  2. South Fork Holston River basin 1988 biomonitoring

    Energy Technology Data Exchange (ETDEWEB)

    Saylor, C.F.; Ahlstedt, S.A.

    1990-06-01

    There is concern over the effects of shifts in land use use practices on the aquatic fauna of streams in the South Fork Holston River basin in northwestern North Carolina and southwestern Virginia. Trout reproduction has noticeably declined in the Watauga River subbasin. The Watauga River and Elk River subbasins have been subjected to commercial and resort development. The Middle fork Holston River and the upper South Fork Holston River subbasins have been affected by agricultural and mining activities, respectively (Cox, 1986). To aid reclamation and management of the South Fork Holston basin, Tennessee Valley Authority (TVA) biologists conducted biomonitoring--including index of biotic integrity and macroinvertebrate sampling--on the Middle Fork Holston, South Fork Holston, Watauga, and Elk Rivers to assess cumulative impairment related to changes in habitat and pollutant loading in these subbasins. Biomonitoring can detect environmental degradation, help document problem areas, and assist in development of strategies for managing water quality. This report discusses the methods and materials and results of the biomonitoring of South Fork Holston River Basin. 13 refs., 5 figs., 12 tabs.

  3. Sea Otter, River Otter. The Wonder Series.

    Science.gov (United States)

    Robinson, Sandra Chisholm

    This curriculum guide is all about otters and provides information on both sea and river otters. Included are activities related to the diet of sea otters, the adaptations sea otters have made to live in the sea, their tool-using abilities, where they live and how to spot them, comparative anatomy of sea and river otters, and otter movement. The…

  4. 33 CFR 117.139 - White River.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false White River. 117.139 Section 117.139 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Arkansas § 117.139 White River. (a) The draws of the St. Louis...

  5. Excessive nitrogen and phosphorus in European rivers

    NARCIS (Netherlands)

    Blaas, Harry; Kroeze, Carolien

    2016-01-01

    Rivers export nutrients to coastal waters. Excess nutrient export may result in harmful algal blooms and hypoxia, affecting biodiversity, fisheries, and recreation. The purpose of this study is to quantify for European rivers (1) the extent to which N and P loads exceed levels that minimize the

  6. Conservation status of Colorado River cutthroat trout

    Science.gov (United States)

    Michael K. Young; R. Nick Schmal; Thomas W. Kohley; Victoria G. Leonard

    1996-01-01

    Though biologists recognize that populations of Colorado River cutthroat trout have declined, the magnitude of the loss remains unquantified. We obtained information from state and federal biologists and from state databases to determine the current distribution and status of populations of Colorado River cutthroat trout. Recent population extinctions have been...

  7. Trends in the occurrence of human and veterinary antibiotics in the sediments of the Yellow River, Hai River and Liao River in northern China

    Energy Technology Data Exchange (ETDEWEB)

    Zhou Lijun [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Ying Guangguo, E-mail: guang-guo.ying@gig.ac.cn [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Zhao Jianliang [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Yang Jifeng [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Chemistry and Chemical Engineering Department, Hunan University of Arts and Science, Changde 415000 (China); Wang Li; Yang Bin; Liu Shan [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2011-07-15

    The occurrence of four classes of 17 commonly used antibiotics (including fluoroquinolones, tetracycline, sulfonamides, and macrolides) was investigated in the sediments of the Yellow River, Hai River and Liao River in northern China by using rapid resolution liquid chromatography-tandem mass spectrometry. Higher concentrations were detected for most antibiotics in the sediments of the Hai River than in the sediments of the other rivers. Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline in the three rivers were most frequently detected with concentrations up to 5770, 1290, 653 and 652 ng/g, respectively. High frequencies and concentrations of the detected antibiotics were often found in the downstream of large cities and areas influenced by feedlot and fish ponds. Good fitted linear regression equations between antibiotic concentration and sediment physicochemical properties (TOC, texture and pH) were also found, indicating that sediment properties are important factors influencing the distribution of antibiotics in the sediment of rivers. - Highlights: > Presence of four classes of commonly used antibiotics in the river sediments. > Higher concentrations in the Hai River than in the Liao River and Yellow River. > Norfloxacin, ofloxacin, ciprofloxacin and oxytetracycline most frequently detected. > High antibiotic concentrations often found in the downstream of large cities. > River sediments are an important reservoir of antibiotics. - Higher concentrations of selected antibiotics were determined in the sediments of the Hai River than in the Liao River and Yellow River.

  8. Ichthyoplankton entrainment study at the SRS Savannah River water intakes for Westinghouse Savannah River Company

    Energy Technology Data Exchange (ETDEWEB)

    Paller, M. (Westinghouse Savannah River Co., Aiken, SC (United States))

    1992-03-26

    Cooling water for L and K Reactors and makeup water for Par Pond is pumped from the Savannah River at the 1G, 3G, and 5G pump houses. Ichthyoplankton (drifting fish larvae and eggs) from the river are entrained into the reactor cooling systems with the river water and passed through the reactor's heat exchangers where temperatures may reach 70[degrees]C during full power operation. Ichthyoplankton mortality under such conditions is assumed to be 100 percent. The number of ichthyoplankton entrained into the cooling system depends on a variety of variables, including time of year, density and distribution of ichthyoplankton in the river, discharge levels in the river, and the volume of water withdrawn by the pumps. Entrainment at the 1 G pump house, which is immediately downstream from the confluence of Upper Three Runs Creek and the Savannah River, is also influenced by discharge rates and ichthyoplankton densities in Upper Three Runs Creek. Because of the anticipated restart of several SRS reactors and the growing concern surrounding striped bass and American shad stocks in the Savannah River, the Department of Energy requested that the Environmental Sciences Section (ESS) of the Savannah River Laboratory sample ichthyoplankton at the SRS Savannah River intakes. Dams Moore, Inc., under a contract with Westinghouse Savannah River Company performed the sampling and data analysis for the ESS.

  9. River-tide dynamics: Exploration of nonstationary and nonlinear tidal behavior in the Yangtze River estuary

    Science.gov (United States)

    Guo, Leicheng; van der Wegen, Mick; Jay, David A.; Matte, Pascal; Wang, Zheng Bing; Roelvink, Dano; He, Qing

    2015-05-01

    River-tide dynamics remain poorly understood, in part because conventional harmonic analysis (HA) does not cope effectively with nonstationary signals. To explore nonstationary behavior of river tides and the modulation effects of river discharge, this work analyzes tidal signals in the Yangtze River estuary using both HA in a nonstationary mode and continuous wavelet transforms (CWT). The Yangtze is an excellent natural laboratory to analyze river tides because of its high and variable flow, its length, and the fact that there are do dams or reflecting barriers within the tidal part of the system. Analysis of tidal frequencies by CWT and analysis of subtidal water level and tidal ranges reveal a broad range of subtidal variations over fortnightly, monthly, semiannual, and annual frequencies driven by subtidal variations in friction and by variable river discharges. We employ HA in a nonstationary mode (NSHA) by segregating data within defined flow ranges into separate analyses. NSHA quantifies the decay of the principal tides and the modulation of M4 tide with increasing river discharges. M4 amplitudes decrease far upriver (landward portion of the estuary) and conversely increase close to the ocean as river discharge increases. The fortnightly frequencies reach an amplitude maximum upriver of that for over tide frequencies, due to the longer wavelength of the fortnightly constituents. These methods and findings should be applicable to large tidal rivers globally and have broad implications regarding management of navigation channels and ecosystems in tidal rivers.

  10. Operational river ice forecasting on the Peace River : managing flood risk and hydropower production

    Energy Technology Data Exchange (ETDEWEB)

    Jasek, M. [BC Hydro, Burnaby, BC (Canada); Friensenhan, E. [Alberta Environment, Edmonton, AB (Canada); Granson, W. [Alberta Environment, Peace River, AB (Canada)

    2007-07-01

    This paper described the procedures used jointly by Alberta Environment and BC Hydro to manage the water flows on the Peace River. The Alberta-British Columbia Joint Task Force on Peace River Ice (JTF) was concerned with the coordination of break-up ice observations along the river as well as ice jam flooding at the Town of Peace River (TPR), resulting from an induced dynamic break-up on the Smoky River, a main tributary of the Peace River. The TPR is the largest community that can be most affected by ice jams on river. As such, river ice processes on the river are monitored and subject to operational procedures of the JTF. These operating procedures are organized into 3 separate sequential phases, notably freeze-up procedures, mid-winter procedures, and break-up procedures. In April 2007, the ice break-up season on the Peace River and Smoky River, was particularly challenging as record high snow cover led to a dynamic break-up of these two streams. Costs due to reduced hydropower production were documented. This paper highlighted the main decision points for mitigation and presented the recommendations that improve mitigation efforts with benefits to both the flood prone community and the power utility. This paper revealed that forecasting the start of control flow by predicting the arrival of the ice front using the Comprehensive River Ice Simulation System Project (CRISSP) model was largely successful. Further work is underway to define the accuracy of forecasting the start of control flow using CRISSP, as accuracy of temperature forecasts appears to be the major uncertainty. The JTF was able to make successful recommendations for flow reductions. However, the need for an accurate hydrologic model for the Smoky River as well as other inflows between Peace Canyon and the TPR was emphasized. 4 refs., 31 figs.

  11. Similarities between rivers and submarine channels

    Science.gov (United States)

    Balcerak, Ernie

    2013-02-01

    Scientists have long known that the width and depth of rivers follows a power law relationship with discharge. They have also noticed that submarine channels appear to be similar to terrestrial rivers, but there have not been many systematic comparisons of the relationships between submarine channel morphology and discharge. Konsoer et al. compared the width, depth, and slope of 177 submarine channels to those of 231 river cross sections. They found that submarine channels are up to an order of magnitude wider and deeper than the largest terrestrial rivers, but they exhibit a similar power law relationship between width and depth. For submarine channels that were similar in size to rivers, the authors found that submarine channels tend to be 1 to 2 orders of magnitude steeper than rivers. The authors also inferred values for sediment concentration in the turbidity currents in the channels and combined this with estimated mean flow velocities to look for a relationship between discharge and morphology in the channels. They found that like rivers, the width and depth of the submarine channels follow a power law scaling with discharge. (Journal of Geophysical Research-Earth Surface, doi:10.1029/2012JF002422, 2013)

  12. River Basin Standards Interoperability Pilot

    Science.gov (United States)

    Pesquer, Lluís; Masó, Joan; Stasch, Christoph

    2016-04-01

    There is a lot of water information and tools in Europe to be applied in the river basin management but fragmentation and a lack of coordination between countries still exists. The European Commission and the member states have financed several research and innovation projects in support of the Water Framework Directive. Only a few of them are using the recently emerging hydrological standards, such as the OGC WaterML 2.0. WaterInnEU is a Horizon 2020 project focused on creating a marketplace to enhance the exploitation of EU funded ICT models, tools, protocols and policy briefs related to water and to establish suitable conditions for new market opportunities based on these offerings. One of WaterInnEU's main goals is to assess the level of standardization and interoperability of these outcomes as a mechanism to integrate ICT-based tools, incorporate open data platforms and generate a palette of interchangeable components that are able to use the water data emerging from the recently proposed open data sharing processes and data models stimulated by initiatives such as the INSPIRE directive. As part of the standardization and interoperability activities in the project, the authors are designing an experiment (RIBASE, the present work) to demonstrate how current ICT-based tools and water data can work in combination with geospatial web services in the Scheldt river basin. The main structure of this experiment, that is the core of the present work, is composed by the following steps: - Extraction of information from river gauges data in OGC WaterML 2.0 format using SOS services (preferably compliant to the OGC SOS 2.0 Hydrology Profile Best Practice). - Model floods using a WPS 2.0, WaterML 2.0 data and weather forecast models as input. - Evaluation of the applicability of Sensor Notification Services in water emergencies. - Open distribution of the input and output data as OGC web services WaterML, / WCS / WFS and with visualization utilities: WMS. The architecture

  13. River Data Package for Hanford Assessments

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, Cynthia L.; Guensch, Gregory R.; Patton, Gregory W.

    2006-08-01

    This data package documents the technical basis for selecting physical and hydraulic parameters and input values that will be used in river modeling for Hanford assessments. This work was originally conducted as part of the Characterization of Systems Task of the Groundwater Remediation Project managed by Fluor Hanford, Inc. and revised as part of the Characterization of Systems Project managed by PNNL for DOE. The river data package provides calculations of flow and transport in the Columbia River system. The module is based on the legacy code for the Modular Aquatic Simulation System II (MASS2), which is a two-dimensional, depth-averaged model that provides the capability to simulate the lateral (bank-to-bank) variation of flow and contaminants. It simulates river hydrodynamics (water velocities and surface elevations), sediment transport, contaminant transport, biotic transport, and sediment-contaminant interaction, including both suspended sediments and bed sediments. This document presents the data assembled to run the river module components for the section of the Columbia River from Vernita Bridge to the confluence with the Yakima River. MASS2 requires data on the river flow rate, downstream water surface elevation, groundwater influx and contaminants flux, background concentrations of contaminants, channel bathymetry, and the bed and suspended sediment properties. Stochastic variability for some input parameters such as partition coefficient (kd) values and background radionuclide concentrations is generated by the Environmental Stochastic Preprocessor. River flow is randomized on a yearly basis. At this time, the conceptual model does not incorporate extreme flooding (for example, 50 to 100 years) or dam removal scenarios.

  14. Visualization of Flow Alternatives, Lower Missouri River

    Science.gov (United States)

    Jacobson, Robert B.; Heuser, Jeanne

    2002-01-01

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

  15. An assessment of water quality of Angaw River in Southeastern ...

    African Journals Online (AJOL)

    Physico-chemical and bacteriological water quality of the Angaw river were investigated at three different locations on the river. A range of water quality variables were measured in the river over a period of 12 months. The river was characterized by high ionic content. Relatively higher levels of ionic constituents occurred at ...

  16. 18 CFR 725.7 - Regional or river basin planning.

    Science.gov (United States)

    2010-04-01

    ... Responsibilities § 725.7 Regional or river basin planning. (a) In agreements between river basin commissions or other regional planning sponsors and the Council for the preparation and revision of regional and river... representing the river basin commission or regional planning sponsor shall certify to the Council that the...

  17. 27 CFR 9.208 - Snake River Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Snake River Valley. 9.208... Snake River Valley. (a) Name. The name of the viticultural area described in this section is “Snake River Valley”. For purposes of part 4 of this chapter, “Snake River Valley” is a term of viticultural...

  18. Water quality of the Modder River, South Africa | Koning | African ...

    African Journals Online (AJOL)

    The Modder River is a relatively small river in the central region of the Free State Province, South Africa and has a mean annual runoff of 184 x 106m3. Botshabelo is a city, which has developed in the catchment area of the river, and its sewage outflows are discharged into the Klein Modder, a tributary of the Modder River.

  19. 76 FR 7837 - Big Rivers Electric Corporation; Notice of Filing

    Science.gov (United States)

    2011-02-11

    ... December 1, 2010, the date that Big Rivers integrated its transmission facilities with the Midwest... Energy Regulatory Commission Big Rivers Electric Corporation; Notice of Filing Take notice that on February 4, 2011, Big Rivers Electric Corporation (Big Rivers) filed a notice of cancellation of its Second...

  20. 27 CFR 9.78 - Ohio River Valley.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Ohio River Valley. 9.78... River Valley. (a) Name. The name of the viticultural area described in this section is “Ohio River Valley.” (b) Approved maps. The approved maps for determining the boundary of the Ohio River Valley...

  1. Hydraulics and morphology of mountain rivers; literature survey

    NARCIS (Netherlands)

    Sieben, J.

    1993-01-01

    Present knowledge on fluvial processes in mountain rivers should be expanded to enable the development of projects dealing with mountain rivers or mountain-river catchment areas. This study reviews research on hydraulic and morphological features of mountain rivers. A major characteristic of

  2. Projected future runoff of the Breede River under climate change ...

    African Journals Online (AJOL)

    The Breede River is the largest river in the Western Cape Province of South Africa, and as such, is a key resource for a variety of activities within the region. It is this significance of the river that prompted a study into the impact of climate change on future runoff in the river and hence, the potential impacts a projected change ...

  3. Radon in water of Shu river valley

    Directory of Open Access Journals (Sweden)

    Yelena Kuyanova

    2012-03-01

    Full Text Available The values of radon and its daughter products in water of Shu River valley have been received, using liquid scintillation spectrometry. The radon concentration naturally increases in investigated water samples downstream the Shu River, reaching the maximum value in the Tashutkolsky basin. The radon and its daughter products in a human body of 15 % are in soft tissues have been calculated by a mathematical modeling method. The annual dose from radon and its daughter products calculated by a mathematical modeling method received by the residents living in Shu river valley is 0,03 mSv/year.

  4. Geodetic monitoring of suspended particles in rivers

    Science.gov (United States)

    Kamnik, Rok; Maksimova, Daria; Kovačič, Boštjan

    2017-10-01

    There is a trend in modern approach to the management of space of collecting the spatial data, in order to obtain useful information. In this paper a research of suspended particles in the river Drava and Mura will be introduced. The goal is to connect different fields of water management in countries where the rivers Drava and Mura flows in purpose of water management sustainability. The methods such as GNSS for mapping cross sections of the river, the use of ADCP (Acoustic Doppler Current Profiler) measurement system and water sampling to monitor sediment in the water will be presented.

  5. Microbial cyanide sensor for monitoring river water.

    Science.gov (United States)

    Ikebukuro, K; Miyata, A; Cho, S J; Nomura, Y; Chang, S M; Yamauchi, Y; Hasebe, Y; Uchiyama, S; Karube, I

    1996-07-18

    A microbial cyanide sensor using Saccharomyces cerevisiae for monitoring a river water is described. This sensor is based on the inhibition of S. cerevisiae's respiration by cyanide. This sensor is a reactor type flow system and composed of two oxygen electrodes and a reactor which contains S. cerevisiae immobilized beads. The S. cerevisiae's respiration activity is measured using the oxygen electrodes. The sensor showed a linear response in the range from 0 to 15 microM and maintained stable response for 9 days at ambient temperature. The sensor was optimized for the monitoring of river water and was applied to river water analysis.

  6. Characterization of the Zymoetz river rock avalanche

    OpenAIRE

    Boultbee, Nichole Leanne

    2005-01-01

    On June 8, 2002, the Pacific Northern Gas pipeline in the Zymoetz River valley was severed over a distance of tens of meters by a large debris flow. The event initiated as a rock avalanche in Glen Falls Creek, a tributary of the 6 3 Zymoetz River. The rock avalanche involved I XI 0 m of volcaniclastic bedrock, and travelled through a complex flow path, to finally deposit a large fan in the main Zymoetz River. Approximately half of the debris volume was deposited in the cirque basin at the hea...

  7. Raft River Geothermal Aquaculture Experiment. Phase II

    Energy Technology Data Exchange (ETDEWEB)

    Campbell, D.K.; Rose, F.L.; Kent, J.C.; Watson, L.R.; Sullivan, J.F.

    1979-08-01

    Channel catfish, tilapia and Malaysian prawns were cultured directly in geothermal water for approximately seven months at the Department of Energy, Raft River Geothermal Site, to evaluate the organisms throughout a grow-out cycle. Parameters evaluated included survival, growth, bioaccumulation of metals and fluoride, collagen synthesis, and bone calcium levels. Growth at Raft River was slightly lower than at a companion commercial facility at Buhl, Idaho, but was attributed to facility differences rather than an adverse impact of geothermal water. No significant differences were recorded between Raft River and Buhl fish for bone calcium or collagen concentrations. No significant accumulation of heavy metals by fish or prawns was recorded.

  8. Old River Control Complex Sedimentation Investigation

    Science.gov (United States)

    2015-06-01

    In an alluvial river, the transport of sediment is tied very closely to the reservoir of sediment available in the sediment bed. Therefore, the...ER D C/ CH L TR -1 5- 8 Old River Control Complex Sedimentation Investigation Co as ta l a nd H yd ra ul ic s La bo ra to ry...acwc.sdp.sirsi.net/client/default. ERDC/CHL TR-15-8 June 2015 Old River Control Complex Sedimentation Investigation Ronald E. Heath, Gary L. Brown

  9. Vaal River catchment: problems and research needs

    CSIR Research Space (South Africa)

    Braune, E

    1987-01-01

    Full Text Available can be divided into four zones on the basis of water quality problems ie the Vaal Dam, the Barrage, the Bloemhof and the Douglas weir subcatchments. In general, the best quality water is found in the catchment of Vaal Dam and quality deteriorates... - 2. THE VAAL RIVER SYSTEM The Vaal River rises on the western slopes of the Drakensberg escarpment and flows about 900 km west-south-west across the interior plateau to join the Orange River near Douglas (Figure 1). The major tributaries...

  10. Count of Sockeye Salmon (Oncorhynchus nerka), River Temperature, and River Height in the Pilgrim River, Nome, Alaska, 2003-2014

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The dataset is the daily count of Sockeye Salmon (Oncorhynchus nerka) passing through a fish counting weir on the Pilgrim River from 2003 to 2014. Also, included in...

  11. River monitoring from satellite radar altimetry in the Zambezi River basin

    DEFF Research Database (Denmark)

    Michailovsky, Claire Irene B.; McEnnis, S.; Berry, P. A. M.

    2012-01-01

    is the assessment of the potential for river monitoring from radar altimetry in terms of water level and discharge in the Zambezi River basin. Retracked Envisat altimetry data were extracted over the Zambezi River basin using a detailed river mask based on Landsat imagery. This allowed for stage measurements......Satellite radar altimetry can be used to monitor surface water levels from space. While current and past altimetry missions were designed to study oceans, retracking the waveforms returned over land allows data to be retrieved for smaller water bodies or narrow rivers. The objective of this study...... to be obtained for rivers down to 80 m wide with an RMSE relative to in situ levels of 0.32 to 0.72 m at different locations. The altimetric levels were then converted to discharge using three different methods adapted to different data-availability scenarios: first with an in situ rating curve available...

  12. The river and the rocks: The geologic story of Great Falls and the Potomac River Gorge

    Science.gov (United States)

    Reed, John Calvin; Sigafoos, Robert Sumner; Fisher, George Wescott

    1980-01-01

    The Great Falls of the Potomac River has figured prominently in the purposes of men since prehistoric time. Long before John Smith reached the falls in 1609, groups of Indians from East and West met at this great river barrier to trade and perform ceremonies in honor of the spirit of the "Roaring Waters". As early as 1754, George Washington visualized the Potomac River as an important avenue of trade and communication with the interior.

  13. 78 FR 59237 - Regulated Navigation Area-Weymouth Fore River, Fore River Bridge Construction, Weymouth and...

    Science.gov (United States)

    2013-09-26

    ...The Coast Guard is establishing a temporary regulated navigation area (RNA) on the navigable waters of Weymouth Fore River in the vicinity of the Fore River Bridge (Mile 3.5) between Weymouth and Quincy, MA. This rule will place temporary speed, wake, and entry restrictions on vessels during bridge replacement operations. This rule is necessary to provide for the safety of life in the vicinity of the Fore River Bridge during its construction.

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

    Science.gov (United States)

    You, Xingying; Tang, Jinwu

    2017-06-01

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

  15. 50 CFR Table 3 to Part 226 - Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River...

    Science.gov (United States)

    2010-10-01

    ... Habitat for Snake River Sockeye Salmon and Snake River Spring/Summer and Fall Chinook Salmon 3 Table 3 to... Part 226—Hydrologic Units Containing Critical Habitat for Snake River Sockeye Salmon and Snake River... Snake—Asotin 17060103 17060103 17060103 Upper Grande Ronde 17060104 Wallowa 17060105 Lower Grande Ronde...

  16. 33 CFR 207.360 - Rainy River, Minn.; logging regulations for portions of river within jurisdiction of the United...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Rainy River, Minn.; logging regulations for portions of river within jurisdiction of the United States. 207.360 Section 207.360 Navigation... REGULATIONS § 207.360 Rainy River, Minn.; logging regulations for portions of river within jurisdiction of the...

  17. 33 CFR 162.80 - Mississippi River below mouth of Ohio River, including South and Southwest passes.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Mississippi River below mouth of Ohio River, including South and Southwest passes. 162.80 Section 162.80 Navigation and Navigable Waters... NAVIGATION REGULATIONS § 162.80 Mississippi River below mouth of Ohio River, including South and Southwest...

  18. 33 CFR 207.200 - Mississippi River below mouth of Ohio River, including South and Southwest Passes; use...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Mississippi River below mouth of Ohio River, including South and Southwest Passes; use, administration, and navigation. 207.200 Section... DEFENSE NAVIGATION REGULATIONS § 207.200 Mississippi River below mouth of Ohio River, including South and...

  19. River Data Package for the 2004 Composite Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rakowski, Cynthia L.; Guensch, Gregory R.; Patton, Gregory W.

    2004-08-01

    Beginning in fiscal year 2003, the DOE Richland Operations Office initiated activities, including the development of data packages, to support the 2004 Composite Analysis. The river data package provides calculations of flow and transport in the Columbia River system. This document presents the data assembled to run the river module components for the section of the Columbia River from Vernita Bridge to the confluence with the Yakima River.

  20. Geochemical characteristics of Heavy metals of river sediment from the main rivers at Texas, USA.

    Science.gov (United States)

    Matsumoto, I.; Hoffman, D.; MacAlister, J.; Ishiga, H.

    2008-12-01

    Trinity River is one of the biggest rivers which flows through Dallas and Fort Worth two big cities of USA and are highly populated. Trinity river drains into the Gulf of Mexico. Sediment samples collected from various points along the upper and lower streams were subjected to content analysis and elution analysis (using liquate (flow) out test) on the heavy metals like Cd, CN, Pb, Cr, As, Hg, Ni, Zn and Cu from the river sediment for the purpose of environment assessment. A total of 22 sample points were identified from upper stream to lower stream and samples were collected such that almost the whole stream length of Trinity River is covered. Results show that heavy metal content through out the river stream is below the recommended limits posing no immediate environmental threat. However, the experimental results show clear impact of human population in bigger cities on heavy metal concentrations in the river sediments as compared to smaller cities with low human population. It could be seen from the analysis that all the heavy metals show relatively high content and high elution value in Dallas and Fort Worth. As we move away from the big cities, the value of content and elution of sediment decreased by natural dilution effect by the river. And we also present the data of the Colorado and San Antonio rivers.

  1. Detection of major river bed changes in the River Ebro (north-eastern Spain)

    Science.gov (United States)

    Espejo, R.; Torrent, J.; Roquero, C.

    1973-01-01

    The application or ERTS-1 data to determine the major river bed changes of the Ebro River in northeastern Spain is discussed. Image quality was good enough to permit a clear identification of the river course and bands MSS 5 and 7 proved to be the most useful for this purpose. Reflectance for band 5 was high due to the high sediment content of the water and sufficed to identify the river. Features like bodies of water related to old channels and depressions were only apparent in band 7.

  2. Contribution of River Mouth Reach to Sediment Load of the Yangtze River

    Directory of Open Access Journals (Sweden)

    C. Wang

    2015-01-01

    Full Text Available This paper examined the sediment gain and loss in the river mouth reach of the Yangtze River by considering sediment load from the local tributaries, erosion/accretion of the river course, impacts of sand mining, and water extraction. A quantitative estimation of the contribution of the river mouth reach to the sediment load of the Yangtze River was conducted before and after impoundment of the Three Gorges Dam (TGD in 2003. The results showed that a net sediment load loss of 1.78 million ton/yr (Mt/yr occurred from 1965 to 2002 in the study area. The contribution of this reach to the sediment discharge into the sea is not as high as what was expected before the TGD. With impoundment of the TGD, channel deposition (29.90 Mt/yr and a net sediment loss of 30.89 Mt/yr occurred in the river mouth reach from 2003 to 2012. The river mouth reach has acted as a sink but not a source of sediment since impoundment of the TGD, which has exacerbated the decrease in sediment load. Technologies should be advanced to measure changes in river channel morphology, as well as in water and sediment discharges at the river mouth reach.

  3. 78 FR 42972 - Notice of Intent To Collect Fees on the John Day River, Oregon

    Science.gov (United States)

    2013-07-18

    ... Bureau of Land Management Notice of Intent To Collect Fees on the John Day River, Oregon AGENCY: Bureau... (River Mile 157) to Tumwater Falls (River Mile 10) stretch of the John Day River, between Service Creek, Oregon, and the confluence of the John Day River and the Columbia River, Oregon. The John Day River...

  4. Onset in-river conductivity sonde data

    Data.gov (United States)

    U.S. Environmental Protection Agency — Onset HOBO Model U24-01 in-river sondes were deployed to measure water temperature and electrical conductivity at each of the ISCO sampling sites at 5 min intervals....

  5. Advanced separations at Savannah River Site

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, M.; McCabe, D.

    1996-10-01

    The Savannah River Site (SRS) has many waste streams that are contaminated with radionuclides and/or hazardous materials that must be treated to remove the radioactivity (cesium, strontium, tritium, actinides) and hazardous components (polychlorinated biphenyls (PCBs), cyanide, metal ions).

  6. SURVIVAL OF SALMONELLA SPECIES IN RIVER WATER.

    Science.gov (United States)

    The survival of four Salmonella strains in river water microcosms was monitored using culturing techniques, direct counts, whole cell hybridization, scanning electron microscopy, and resuscitation techniques via the direct viable count method and flow cytrometry. Plate counts of...

  7. Studies of mineralization in South African rivers

    CSIR Research Space (South Africa)

    Hall, GC

    1978-03-01

    Full Text Available Several South African rivers are polluted by mineral salts of diffuse source. This pollution can be related to geological phenomena and to irrigation practices. Mineralization is problematic in that it can render surface waters unsuitable...

  8. Parker River National Wildlife Refuge : Refuge Objectives

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document lists the objectives of Parker River National Wildlife Refuge. Topics outlined in this plan include wildlife-wildlands interpretation,...

  9. Heavy metals in Mindhola river estuary, India

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Rokade, M.A; Mandalia, A

    The heavy metal concentrations are studied along the Mindhola river estuary. Surface and bottom water samples were collected using Niskin Sampler. The sediment samples were collected using a Van Veen grab. The heavy metal concentration is estimated...

  10. Umpqua River Oregon Active Channel 2000

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of...

  11. Savannah River Site Environmental Report for 1997

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M.W.; Mamatey, A.R. [eds.

    1998-08-01

    The mission at the Savannah River Site has changed from the production of nuclear weapons materials for national defense to the management of waste, restoration of the environment, and the development of industry in and around the site.

  12. Delaware River and Upper Bay Sediment Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The area of coverage consists of 192 square miles of benthic habitat mapped from 2005 to 2007 in the Delaware River and Upper Delaware Bay. The bottom sediment map...

  13. Columbia River ESI: FISH (Fish Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for marine, estuarine, anadromous, and freshwater fish species in Columbia River. Vector polygons in this...

  14. Columbia River ESI: NESTS (Nest Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for bird nesting sites in the Columbia River area. Vector points in this data set represent locations of...

  15. Umpqua River Oregon Active Channel 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of...

  16. Umpqua River Oregon Active Channel 2005

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of...

  17. Umpqua River Oregon Active Channel 1994

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of...

  18. Umpqua River Oregon Active Channel 1939

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Umpqua River drains 12,103 square kilometers (4,673 square miles) in southwest Oregon before flowing into the Pacific Ocean at Winchester Bay near the city of...

  19. 2015 OLC FEMA Lidar: Snake River, ID

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Quantum Spatial has collected Light Detection and Ranging (LiDAR) data for the Oregon LiDAR Consortium (OLC) Snake River FEMA study area. This study area is located...

  20. Flood tracking chart, Amite River Basin, Louisiana

    Science.gov (United States)

    Callender, Lawrence E.; McCallum, Brian E.; Brazelton, Sebastian R.; Anderson, Mary L.; Ensminger, Paul A.

    1998-01-01

    The Amite River Basin flood tracking chart is designed to assist emergency response officials and the local public in making informed decisions about the safety of life and property during floods along the Amite and Comite Rivers and Bayou Manchac in southeastern Louisiana. This chart is similar in concept to the charts used to track hurricanes; the user can record the latest river stage information at selected gaging stations and the latest flood crest predictions. The latest stage data can be compared to historical flood peaks as well as to the slab or pier elevation of a threatened property. The chart also discusses how to acquire the latest river stage data from the Internet and a recorded voice message.

  1. DNR 100K Lakes and Rivers

    Data.gov (United States)

    Minnesota Department of Natural Resources — Polygons representing hydrographic features (lakes, ponds, some rivers, and open water areas) originating from the USGS 1:100,000 (100K)DLG (Digital Line Graph)...

  2. Ecological flow requirements for South African rivers

    CSIR Research Space (South Africa)

    Ferrar, AA

    1989-01-01

    Full Text Available This document contains the proceedings of a workshop which was convened to debate the ecological flow requirements of South African rivers. Topics which are discussed include the influence of weirs and impoundments, the quantity requirements...

  3. Parker River NWR : Revised Hunting Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document contains revisions to the 1978 Parker River National Wildlife Refuge Hunt Management Plan. Refuge hunters must obtain a permit to use the hunting...

  4. Savannah River Site environmental data for 1995

    Energy Technology Data Exchange (ETDEWEB)

    Arnett, M.W. [ed.

    1995-12-31

    This document presents data from Savannah River Site routine environmental monitoring and surveillance programs. An attempt also has been made to include all available data from environmental research programs.

  5. Offshore extension of Gomati river, Dwarka

    Digital Repository Service at National Institute of Oceanography (India)

    Vora, K.H.; Naik, D.K.; Ganesan, P.; Moraes, C.

    information. Attempts have been made to identify the submerged extension of Gomati River by diving inspection and based on the results obtained such as findings like stone and iron anchors, circular bastions, etc. While many features reported earlier...

  6. Radionuclide transport in the Yenisei River

    CERN Document Server

    Vakulovsky, S M; Kabanov, A I

    2012-01-01

    Data characterizing the pollution of the Yenisei River (water and bottom sediment) by radionuclide resulting from the use of the river water for cooling industrial reactors in the Mining-Chemical Complex are presented. Studies have been made of the contamination of the river during the period when reactors with direct flow cooling were used and after these were shut down. Distinctive features of the migration of radionuclide in the Yenisei are noted, in particular, their distribution between the solid and liquid phases. The amounts of 137Cs, 65Zn, 60Co, 54Mn, and 152Eu in the channel are determined from the effluent discharge site to Dudinka port. The rate of continuous self removal of 137Cs is estimated to be 0.19 1/year, corresponding to a half purification time of 3.6 years for a 600 km long segment of the river bed.

  7. Raft River geoscience case study: appendixes

    Energy Technology Data Exchange (ETDEWEB)

    Dolenc, M.R.; Hull, L.C.; Mizell, S.A.; Russell, B.F.; Skiba, P.A.; Strawn, J.A.; Tullis, J.A.

    1981-11-01

    The following are included in these appendices: lithology, x-ray analysis, and cores; well construction data; borehole geophysical logs; chemical analyses from wells at the Raft River geothermal site; and bibliography. (MHR)

  8. Trace metal pollution in Umtata River

    African Journals Online (AJOL)

    drinie

    2002-04-02

    Apr 2, 2002 ... Dissolved trace metals, i.e Fe, Mn, Al, Cu, Zn, Pb and Cd were determined in ..... River Catchment Preliminary Framework for the Development of an ... FRIES J and GETROST H (1977) Organic Reagents for Trace Analysis.

  9. Middle Mississippi River Sturgeon Preliminary Contaminants Investigation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We examined the health of forty-one wild caught sturgeon from a reach of the Mississippi River with an organochlorine consumption advisory and a reference site. The...

  10. Contaminant levels in the Sudbury River, Massachusetts

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Great Meadows National Wildlife Refuge sits astride the Concord and Sudbury Rivers in portions of the towns of Bedford, Billerica, Lincoln, Carlisle, Concord, and...

  11. Implementing Integrated River Basin Management in China

    Directory of Open Access Journals (Sweden)

    Dorri G. J. te Boekhorst

    2010-06-01

    Full Text Available This paper examines the role of the World Wildlife Fund for Nature China as policy entrepreneur in China. It illustrates the ways in which the World Wildlife Fund for Nature is active in promoting integrated river basin management in the Yangtze River basin and how the efforts at basin level are matched with the advice of the China Council for International Cooperation on Environment and Development task force on integrated river basin management to the national government of China. This article demonstrates that the World Wildlife Fund for Nature uses various strategies of different types to support a transition process towards integrated river basin management. Successful deployment of these strategies for change in environmental policy requires special skills, actions, and attitudes on the part of the policy entrepreneur, especially in China, where the government has a dominant role regarding water management and the position of policy entrepeneurs is delicate.

  12. 1999 Yellow River Aerial Photos, Central Wisconsin

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The 25-mile stretch of the Yellow River adjacent to the Necedah National Wildlife Refuge in Central Wisconsin provides valuable habitat to numerous species of...

  13. Anthropogenic impacts on global organic river pollution

    NARCIS (Netherlands)

    Wen, Y.

    2017-01-01

    Organic pollution of rivers by wastewater discharge from human activities negatively impacts people and ecosystems. Without treatment, pollution control relies on a combination of natural degradation and dilution by natural runoff to reduce downstream effects. To implement integrated water

  14. Little River NWR Inventory and Monitoring Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This Inventory and Monitoring Plan for Little River National Wildlife Refuge is a step-down from the Comprehensive Conservation Plan and Forest Habitat Management...

  15. Savannah River Technology Center, monthly report

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-01

    This is the monthly report to detail the research currently being conducted at the Savannah River Technology Center. The areas of research are in Tritium, Seperation processes, Environmental Engineering, and Waste Management.

  16. Columbia River ESI: INVERT (Invertebrate Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for clams, oysters, crabs, and other invertebrate species in Columbia River. Vector polygons in this data...

  17. American River Watershed Investigation, California. Reconnaisance Report

    National Research Council Canada - National Science Library

    1988-01-01

    .... The report describes studies of alternative measures for flood control in the American River Watershed predicated on the assumption that Auburn Dam as previously authorized will not be constructed...

  18. Using river locks to teach hydrodynamic concepts

    CERN Document Server

    Carvalho-Santos, Vagson L; Silva, Enisvaldo C; Rios, Márcio L; Silva, Anderson A P

    2013-01-01

    In this work, the use of a river lock as a non-formal setting for teaching Q2 hydrodynamical concepts is proposed. In particular, we describe the operation of a river lock situated at the Sobradinho dam, on the S\\~ao Francisco River (Brazil). A model to represent and to analyse the dynamics of river lock operation is presented and we derive the dynamical equations for the rising of the water column as an example to understand the Euler equation. Furthermore, with this activity, we enable the integration of content initially introduced in the classroom with practical applications, thereby allowing the association of physical themes to content relevant in disciplines such as history and geography. In addition, experiences of this kind enable teachers to talk about the environmental and social impacts caused by the construction of a dam and, consequently, a crossover of concepts has been made possible, leading to more meaningful learning for the students.

  19. Columbia River ESI: MGT (Management Area Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive human-use data for Wildlife Refuges, National Forests, and State Parks for the Columbia River area. Vector polygons in this data set...

  20. Assessing river health in Europe and Switzerland

    Science.gov (United States)

    Milano, Marianne; Chèvre, Nathalie; Reynard, Emmanuel

    2017-04-01

    River conditions and welfare of aquatic ecosystems are threatened by anthropogenic and climatic changes. The release of personal-care products, pharmaceuticals and crop protection products is increasing and climate change is likely to cause significant changes in hydrological regimes affecting water resources' capacity to dissolve pollutants. Assessing river health, i.e. the ability of a river to support and maintain a balanced ecosystem close to the natural habitat, is thus of major concern to ensure the development of ecosystems and to provide enough clean useable water to users. Such studies involve physical, chemical and biological processes and characteristics. In Europe and Switzerland, standardized procedures have been developed to assess the hydromorphological, ecological and toxicological status of rivers. The European Water Framework Directive sets ecological requirements and chemical guidelines while the Swiss Modular Stepwise Procedure suggests methods to apprehend ecological deficits and promote water management plans. In this study, both procedures were applied and compared in order (i) to address their capacity to follow-up the spatial and temporal variability of the river's water quality and (ii) to identify challenges that still need to be addressed to assess river's health. Applied on the Boiron River (canton of Vaud, Switzerland) for a 11-year period (2005-2015), both frameworks highlight that no section of the river currently meets a good environmental state. This river flows through a diversified agricultural area causing a progressive deterioration of its chemical and biological quality. The two methods also identify two periods of time with significant changes of the river's water quality. The 2009-2011 period is characterized by a significant deterioration of the river's ecological and toxicological state due to severe low flows and an increased use of pesticides. However, since 2013, an improvement in water quality is identified in

  1. Gammaridean amphipods in the Columbia River Estuary

    Energy Technology Data Exchange (ETDEWEB)

    Holton, R.L.; Higley, D.L.

    1976-01-01

    The distribution, abundance, and habitat preference of the amphipods Corophium salmonis, C. spinicorne, and Anisogammarus confervicolus were studied in the Columbia River estuary as part of baseline research during 1974 to 1976. A figure is presented showing densities of two species at selected stations in the Columbia River. Studies were also conducted on changes in faunal composition and substrate texture existing across an intertidal mudflat on the southwest shore of Youngs Bay. (HLW)

  2. Flora of the Mediterranean Rivers in Bulgaria

    OpenAIRE

    Yordanka G. Hristeva; Gana M. Gecheva; Karin Pall

    2015-01-01

    Species composition and distribution of aquatic bryophytes and vascular plants assemblages in Mediteranean Rivers in Bulgaria are presented in this work. Aquatic macrophytes were studied at thirteen rivers in South Bulgaria during 2014, together with abiotic factors (flow velocity, shading, and substrate type), mean depth and altitude. In total, 73 species were registered, of them 13 bryophytes and 60 vascular plants were identified. Aquatic bryophytes included 10 mosses and 3 liverworts. The...

  3. CHEMICAL COMPOSITION FROM THE DNIESTER RIVER TRIBUTARIES

    Directory of Open Access Journals (Sweden)

    V. Gladchi

    2013-06-01

    Full Text Available This article presents the results obtained in the framework of the project 09.832.08.06A. The role of the tributaries on formation of the Dniester river water and the study of the waters quality of sources / fountains in the catchment area of the Dniester river as sources of water supply and for irrigation in the State Program, Scientific Researches and of the management of waters quality.

  4. THE RIVER BASIN APPROACH IN TOURISM PLANNING

    OpenAIRE

    Agita Slara

    2005-01-01

    The article describes advantages and disadvantages in tourism planning, using the river basins as background territory and borders. Tourism development planning is taking place according administrative territorial borders till nowadays in Latvia and in other tourism destinations in abroad. According tourist and visitor needs and environmental friendly approach it is more appropriate to use river basins in tourism planning. Tourists are not interested in administrative borders, but in qualitat...

  5. Morphology of Tigris River within Baghdad City

    Directory of Open Access Journals (Sweden)

    A. A. Ali

    2012-10-01

    Full Text Available In recent years, substantial changes have occurred in the morphology of the River Tigris within Baghdad City. Although huge volumes of sediment are being trapped in recently constructed headwater reservoirs, the number of islands in the Tigris at Baghdad is increasing. The debris of bridges destroyed in the wars of 1991 and 2003 and their subsequent reconstruction have enhanced the development of these islands. As a consequence the ability of the river to carry the peaks of flood waters has been reduced. This has led to potential increase of flooding in parts of the city.

    The bed of the River Tigris has been surveyed on three occasions (1976, 1991, and 2008. The most recent survey was conducted by the Ministry of Water Resources, extended 49 km from the Al-Muthana Bridge north Baghdad to the confluence with the Diyala River south Baghdad. It yielded cross-section profiles at 250 m intervals. The data are used to predict the maximum flood capacity for the river using the one-dimensional hydraulic model for steady flow "HEC-RAS" modeling. Calibration of the model was carried out using field measurements for water levels along the last 15 km of the reach and the last 10 yr of observation at the Sarai Baghdad gauging station.

    The model showed a significant predicted reduction in the current river capacity below that which the river had carried during the floods of 1971 and 1988. The three surveys conducted on the same reach of the Tigris indicated that the ability of the river to transport water has decreased.

  6. Columbia River Component Data Gap Analysis

    Energy Technology Data Exchange (ETDEWEB)

    L. C. Hulstrom

    2007-10-23

    This Data Gap Analysis report documents the results of a study conducted by Washington Closure Hanford (WCH) to compile and reivew the currently available surface water and sediment data for the Columbia River near and downstream of the Hanford Site. This Data Gap Analysis study was conducted to review the adequacy of the existing surface water and sediment data set from the Columbia River, with specific reference to the use of the data in future site characterization and screening level risk assessments.

  7. River network routing on the NHDPlus dataset

    OpenAIRE

    David, Cédric,; Maidment, David,; Niu, Guo-Yue; Yang, Zong-Liang; Habets, Florence; Eijkhout, Victor

    2011-01-01

    International audience; The mapped rivers and streams of the contiguous United States are available in a geographic information system (GIS) dataset called National Hydrography Dataset Plus (NHDPlus). This hydrographic dataset has about 3 million river and water body reaches along with information on how they are connected into net- works. The U.S. Geological Survey (USGS) National Water Information System (NWIS) provides stream- flow observations at about 20 thousand gauges located on theNHDP...

  8. Salmon River Habitat Enhancement. 1990 Annual Report

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mike

    1991-12-01

    The annual report contains three individual subproject sections detailing tribal fisheries work completed during the summer and fall of 1990. Subproject I contains summaries of evaluation/monitoring efforts associated with the Bear Valley Creek, Idaho enhancement project. Subproject II contains an evaluation of the Yankee Fork of the Salmon River habitat enhancement project. Subproject III concerns the East Fork of the Salmon River, Idaho.

  9. Ecological state of the river Ural

    Directory of Open Access Journals (Sweden)

    Gul'zhamal Tulemisova

    2017-09-01

    Full Text Available The article describes the ecological state of the Ural River at the present stage. Hydrochemical regime of the reservoir is an important indicator to regulating the number of water resources. As the Ural River is the transboundary reservoir, it is prone to contamination from various areas in the upper and middle reaches. Monitoring of the ecological state of the Ural River showed the presence of anthropogenic pollution. The hydrochemical regime of the reservoir is subject to changes in seasonal variations in water composition. In spring, with flood waters, the main pollution enters the river, however in other seasons, the quality of water leaves much to be desired. In autumn, in comparison with the spring, both alkalinity and salinity increased. The reservoir is prone to contamination with nitrites in almost all seasons of the year from 0.05 to 0.20 mg/dm3 (December, 2016. In the lower reaches of the Ural River, the content of readily oxidizable organic compounds ranges from 3.2 mg/dm3 (winter to 7.36 mg/dm3 (autumn. The content of boron exceeds the maximum permissible concentration 1-3 times. Environmental monitoring conducted in different periods of the year showed a constant source of pollution flow into the reservoir, which was increased in the flood period. Concentrations of nitrite, boron and petroleum products in the Ural River exceed their permitted values at the point in the end of Uralsk city. The results of the research confirm that the source of the contamination of Ural River is its confluent Ilek River originating from Aktobe Oblast.

  10. New River Valley Agriculture & Agritourism Strategic Plan

    OpenAIRE

    Walker, Martha A.; Scott, Kelli H.

    2017-01-01

    This strategic plan discusses plans for improving the marketing of agritourism and agribusiness in the New River Valley (Floyd, Giles, Montgomery and Pulaski Counties), and potentially increasing community wealth while improving the access to local crops and products. Includes Planning for an Agricultural Future in Giles, Montgomery, and Pulaski Counties: An Agricultural Regional Assessment, prepare for the New River Valley Agricultural & Agritourism Project Management Team by Matson Consu...

  11. Interoperability challenges in river discharge modelling

    Science.gov (United States)

    Santoro, Mattia; Schlummer, Manuela; Andres, Volker; Jirka, Simon; Looser, Ulrich; Mladek, Richard; Pappenberger, Florian; Strauch, Adrian; Utech, Michael; Zsoter, Ervin

    2014-05-01

    River discharge is a critical water cycle variable, as it integrates all the processes (e.g. runoff and evapotranspiration) occurring within a river basin and provides a hydrological output variable that can be readily measured. Its prediction is of invaluable help for many water-related areas such as water resources assessment and management, as well as flood protection and disaster mitigation. Observations of river discharge are very important for the calibration and validation of hydrological or coupled land, atmosphere and ocean models . This requires the use of data from different scientific domains (Water, Weather, etc.). Typically, such data are provided using different technological solutions and formats. This complicates the integration of new hydrological data sources into application systems. Therefore, a considerable effort is often spent on data access issues instead of the actual scientific question. In the context of the FP7 funded project GEOWOW (GEOSS Interoperability for Weather, Ocean and Water), the "River Discharge" use scenario was developed in order to combine river discharge observations data from the Global Runoff Data Center (GRDC) database and model outputs produced by the European Centre for Medium-Range Weather Forecasts (ECMWF) predicting river discharge based on weather forecast information. In this presentation we describe interoperability solutions which were adopted in order to address the technological challenges of the "River Discharge" use scenario: 1) Development of a Hydrology Profile for the OGC SOS 2.0 standard; 2) Enhancement of the GEO DAB (Discovery and Access Broker) to support the use scenario: 2.1) Develop new interoperability arrangements for GRDC and ECMWF capacities; 2.2) Select multiple time series for comparison. The development of the above functionalities and tools aims to respond to the need of Water and Weather scientists to assess river discharge forecasting models.

  12. Hydrogeochemical characteristics of the River Idrijca (Slovenia

    Directory of Open Access Journals (Sweden)

    Tjaša Kanduč

    2008-06-01

    Full Text Available The hydrogeochemical and isotope characteristics of the River Idrijca, Slovenia, where the world’s second largest mercury (Hg mine is located, were investigated. The River Idrijca, a typical steep mountain river has an HCO3- - Ca2+ - Mg2+ chemical composition. Its Ca2+/Mg2+ molar ratio indicates that dolomite weathering prevails in the watershed. The River Idrijca and its tributaries are over saturated with respect to calcite and dolomite. The pCO2 pressure is up to 13 times over atmospheric pressure and represents a source of CO2 to the atmosphere. δ18O values in river water indicate primary control from precipitation and enrichment of the heavy oxygen isotope of infiltrating water recharging the River Idrijca from its slopes.The δ13 CDIC values range from −10.8 to −6.6 ‰ and are controlled by biogeochemical processes in terrestrial environments and in the stream: 1 exchange with atmospheric CO2, 2 degradation of organic matter, 3 dissolution of carbonates, and 4 tributaries. The contributions of these inputs were calculated according to steady state equations and are estimated to be -11 %: 19 %: 31 %: 61 % in the autumn and 0 %: 6 %: 9 %: 35 % in the spring sampling seasons.

  13. The Columbia River System : the Inside Story.

    Energy Technology Data Exchange (ETDEWEB)

    United States. Bonneville Power Administration.

    1991-09-01

    The Columbia Ricer is one of the greatest natural resources in the western United States. The river and its tributaries touch the lives of nearly every resident of the Northwest-from providing the world-famous Pacific salmon to supplying the clean natural fuel for over 75 percent of the region's electrical generation. Since early in the century, public and private agencies have labored to capture the benefits of this dynamic river. Today, dozens of major water resource projects throughout the region are fed by the waters of the Columbia Basin river system. And through cooperative efforts, the floods that periodically threaten developments near the river can be controlled. This publication presents a detailed explanation of the planning and operation of the multiple-use dams and reservoirs of the Columbia River system. It describes the river system, those who operate and use it, the agreements and policies that guide system operation, and annual planning for multiple-use operation.

  14. Climate change characteristics of Amur River

    Directory of Open Access Journals (Sweden)

    Lan-lan YU

    2013-04-01

    Full Text Available Unusually severe weather is occurring more frequently due to global climate change. Heat waves, rainstorms, snowstorms, and droughts are becoming increasingly common all over the world, threatening human lives and property. Both temperature and precipitation are representative variables usually used to directly reflect and forecast the influences of climate change. In this study, daily data (from 1953 to 1995 and monthly data (from 1950 to 2010 of temperature and precipitation in five regions of the Amur River were examined. The significance of changes in temperature and precipitation was tested using the Mann-Kendall test method. The amplitudes were computed using the linear least-squares regression model, and the extreme temperature and precipitation were analyzed using hydrological statistical methods. The results show the following: the mean annual temperature increased significantly from 1950 to 2010 in the five regions, mainly due to the warming in spring and winter; the annual precipitation changed significantly from 1950 to 2010 only in the lower mainstream of the Amur River; the frequency of extremely low temperature events decreased from 1953 to 1995 in the mainstream of the Amur River; the frequency of high temperature events increased from 1953 to 1995 in the mainstream of the Amur River; and the frequency of extreme precipitation events did not change significantly from 1953 to 1995 in the mainstream of the Amur River. This study provides a valuable theoretical basis for settling disputes between China and Russia on sustainable development and utilization of water resources of the Amur River.

  15. Computational Modeling of Pollution Transmission in Rivers

    Science.gov (United States)

    Parsaie, Abbas; Haghiabi, Amir Hamzeh

    2017-06-01

    Modeling of river pollution contributes to better management of water quality and this will lead to the improvement of human health. The advection dispersion equation (ADE) is the government equation on pollutant transmission in the river. Modeling the pollution transmission includes numerical solution of the ADE and estimating the longitudinal dispersion coefficient (LDC). In this paper, a novel approach is proposed for numerical modeling of the pollution transmission in rivers. It is related to use both finite volume method as numerical method and artificial neural network (ANN) as soft computing technique together in simulation. In this approach, the result of the ANN for predicting the LDC was considered as input parameter for the numerical solution of the ADE. To validate the model performance in real engineering problems, the pollutant transmission in Severn River has been simulated. Comparison of the final model results with measured data of the Severn River showed that the model has good performance. Predicting the LDC by ANN model significantly improved the accuracy of computer simulation of the pollution transmission in river.

  16. Morphological convergence in 'river dolphin' skulls.

    Science.gov (United States)

    Page, Charlotte E; Cooper, Natalie

    2017-01-01

    Convergent evolution can provide insights into the predictability of, and constraints on, the evolution of biodiversity. One striking example of convergence is seen in the 'river dolphins'. The four dolphin genera that make up the 'river dolphins' ( Inia geoffrensis, Pontoporia blainvillei, Platanista gangetica and Lipotes vexillifer ) do not represent a single monophyletic group, despite being very similar in morphology. This has led many to using the 'river dolphins' as an example of convergent evolution. We investigate whether the skulls of the four 'river dolphin' genera are convergent when compared to other toothed dolphin taxa in addition to identifying convergent cranial and mandibular features. We use geometric morphometrics to uncover shape variation in the skulls of the 'river dolphins' and then apply a number of phylogenetic techniques to test for convergence. We find significant convergence in the skull morphology of the 'river dolphins'. The four genera seem to have evolved similar skull shapes, leading to a convergent morphotype characterised by elongation of skull features. The cause of this morphological convergence remains unclear. However, the features we uncover as convergent, in particular elongation of the rostrum, support hypotheses of shared feeding mode or diet and thus provide the foundation for future work into convergence within the Odontoceti.

  17. Migration of radionuclides through a river system

    Energy Technology Data Exchange (ETDEWEB)

    Matsunaga, Takeshi [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    1999-03-01

    Migration behavior of several atmospherically-derived radionuclides in a river watershed was studied. A main interest was in their relocation from the ground soil of the watershed to a downstream region through a river. Studied radionuclides are: {sup 137}Cs generated by weapon tests in the atmosphere; {sup 210}Pb and {sup 7}Be of naturally occurring radionuclides; {sup 137}Cs, {sup 90}Sr, {sup 239,240}Pu and {sup 241}Am released by the Chernobyl nuclear power plant accident. Dominance of the form in suspended solid in river water (particulate form) was qualified for the radionuclides in the Kuji river watershed. An importance of discharge in flooding was also confirmed. A historical budget analysis for weapon test derived {sup 137}Cs was presented for the Hi-i river watershed and its accompanied lake sediment (Lake Shinji). The work afforded a scheme of a fate of {sup 137}Cs after falling on the ground soil and on the lake surface. Several controlling factors, which can influence on the chemical form of radionuclides discharged to a river, were also investigated in the vicinity of the Chernobyl nuclear power plant. A special attention was paid on the association of the radionuclides with dissolved species in water. Preferential association of Pu and Am isotopes to a large molecular size of dissolved matrices, probably of humic substances, was suggested. (author)

  18. The Mechanics of River Avulsions on Deltas

    Science.gov (United States)

    Ganti, Vamsi; Chadwick, Austin; Hassenruck-Gudipati, Hima; Lamb, Michael

    2017-04-01

    River deltas are highly dynamic, often fan-shaped depositional systems that form when rivers drain into a standing body of water. They host over a half billion people worldwide and are currently under threat of drowning and destruction by relative sea-level rise, subsidence, and anthropogenic interference. Many river deltas develop planform fan shapes through avulsions, whereby major river channel shifts occur via "channel jumping" about a persistent spatial node, thus determining their fundamental length scale. Emerging theories suggest that the size of deltas is set by backwater hydrodynamics; however, these ideas are difficult to test on natural deltas, which evolve on centennial to millennial timescales. Here, using physical experiments coupled with observations of the dynamics of modern deltaic evolution, we show that deltas grow through successive deposition of lobes that maintain a constant size that scales with backwater hydrodynamics. The preferential avulsion node in our experiments is a consequence of multiple river floods and Froude-subcritical flows that produce persistent nonuniform flows and a peak in net channel deposition within the backwater zone of the coastal river. Moreover, because the backwater hydrodynamics are controlled by the downstream boundary condition of constant sea level, the backwater-mediated avulsion sites translate seaward in step with shoreline progradation. In contrast, experimental deltas without multiple floods produce flows with uniform velocities and delta lobes that lack a characteristic size. Results have broad applications to sustainable management of deltas and for decoding their stratigraphic record on Earth and Mars.

  19. Statistical dynamics of early river networks

    Science.gov (United States)

    Wang, Xu-Ming; Wang, Peng; Zhang, Ping; Hao, Rui; Huo, Jie

    2012-10-01

    Based on local erosion rule and fluctuations in rainfall, geology and parameters of a river channel, a generalized Langevin equation is proposed to describe the random prolongation of a river channel. This equation is transformed into the Fokker-Plank equation to follow the early evolution of a river network and the variation of probability distribution of channel lengths. The general solution of the equation is in the product form of two terms. One term is in power form and the other is in exponent form. This distribution shows a complete history of a river network evolving from its infancy to “adulthood”). The infancy is characterized by the Gaussian distribution of the channel lengths, while the adulthood is marked by a power law distribution of the channel lengths. The variation of the distribution from the Gaussian to the power law displays a gradual developing progress of the river network. The distribution of basin areas is obtained by means of Hack's law. These provide us with new understandings towards river networks.

  20. Using array seismology to quantify river physics

    Science.gov (United States)

    Gimbert, F.

    2016-12-01

    Seismic ground motion measurements nearby rivers are sensitive to bedload sediment transport and turbulent fluid flow operating at river beds, both of which are major control on fluvial erosion but yet remain poorly known due to lacking observations. Seismic observations thus provide a valuable opportunity to improve our understanding of fluvial dynamics and its control on crustal erosion. However, although recently proposed theoretical frameworks provided solid grounds to link fluvial processes with seismic signal properties, a better understanding of river physics from seismic signals needs investigating turbulent flow and bedload seismic source functions from direct field observations. Here we use seismic array processing to invert river seismic source force functions and discuss the various river mechanisms that control properties of the seismic wave field. We report new seismic measurements conducted under various flow conditions at two mountain rivers with drastically different geometries: the narrow (1 m), steep ( 5 to 15%) and shallow flows ( 10 to 40 cm deep) of the Les Bossons River (Chamonix, French Alps), and the much wider ( 50 m), gentler ( 1 to 2%) and deeper flows ( 2 to 4 m deep) of the Kali Gandaki River (Lete, Nepal Himalayas). At these sites, we invert for ground velocity structure and river seismic source characteristics from the analysis of both impulsive arrivals and the continuous noise field. We report distinct spectral and directional properties between the sediment transport and the turbulent flow sources. We relate source force characteristics to physical components of sediment transport and turbulent flow dynamics such as mainly the directionality of grain impacts and the associated grain transport modes (saltation, rolling, sliding), as well as the directionality of fluid forces applied on river bed grains and the respective drag, lift and cross stream forces. To our knowledge, this is the first time that such physics of bedload

  1. River Water Quality Zoning: A Case Study of Karoon and Dez River System

    Directory of Open Access Journals (Sweden)

    M Karamouz, N Mahjouri, R Kerachian

    2004-10-01

    Full Text Available Karoon-Dez River basin, with an area of 67000 square kilometers, is located in southern part of Iran. This river system supplies the water demands of 16 cities, several villages, thousands hectares of agricultural lands, and several hydropower plants. The increasing water demands at the project development stage including agricultural networks, fish hatchery projects, and inter-basin water transfers, have caused a gloomy future for water quality of the Karoon and Dez Rivers. A good part of used agricultural water, which is about 8040 million cubic meters, is returned to the rivers through agricultural drainage systems or as non-point, return flows. River water quality zoning could provide essential information for developing river water quality management policies. In this paper, a methodology is presented for this purpose using methods of -mean crisp classification and a fuzzy clustering scheme. The efficiency of these clustering methods was evaluated using water quality data gathered from the monitoring sampling points along Karoon and Dez Rivers. The results show that the proposed methodology can provide valuable information to support decision-making and to help river water quality management in the region.

  2. Restoration strategies for river floodplains along large lowland rivers in Europe

    NARCIS (Netherlands)

    Buijse, A.D.; Coops, H.; Staras, M.; Jans, L.H.; Van Geest, G.J.; Grift, R.E.; Ibelings, B.W.; Oosterberg, W.; Roozen, F.C.J.M.

    2002-01-01

    1. Most temperate rivers are heavily regulated and characterised by incised channels, aggradated floodplains and modified hydroperiods. As a consequence, former extensive aquatic /terrestrial transition zones lack most of their basic ecological functions. 2. Along large rivers in Europe and North

  3. Restoration strategies for river floodplains along large lowland rivers in Europe

    NARCIS (Netherlands)

    Buijse, A.D.; Coops, H.; Staras, M.; Jans, L.H.; Geest, van G.; Grift, R.E.; Ibelings, B.W.; Oosterberg, W.; Roozen, F.C.J.M.

    2002-01-01

    1. Most temperate rivers are heavily regulated and characterised by incised channels, aggradated floodplains and modified hydroperiods. As a consequence, former extensive aquatic/terrestrial transition zones lack most of their basic ecological functions. 2. Along large rivers in Europe and North

  4. Global river temperatures and sensitivity to atmospheric warming and changes in river flow

    NARCIS (Netherlands)

    Vliet, van M.T.H.; Ludwig, F.; Zwolsman, J.J.G.; Weedon, G.P.; Kabat, P.

    2011-01-01

    This study investigates the impact of both air temperature and river discharge changes on daily water temperatures for river stations globally. A nonlinear water temperature regression model was adapted to include discharge as a variable in addition to air temperature, and a time lag was

  5. Bank retreat study of a meandering river reach case study : River Irwell

    NARCIS (Netherlands)

    Duran, R.; Beevers, L.; Crosato, A.; Wright, N.

    2010-01-01

    Lack of data is often considered a limitation when undertaking morphological studies. This research deals with morphological studies of small rivers experiencing bank erosion processes when only limited data are available. A reach of the meandering gravel-bed river Irwell (United Kingdom) is taken

  6. River flow modeling using artificial neural networks in Kapuas river, West Kalimantan, Indonesia

    Science.gov (United States)

    Herawati, Henny; Suripin, Suharyanto

    2017-11-01

    Kapuas River is located in the province of West Kalimantan. Kapuas river length is 1,086 km and river basin areas about 100,000 Km2. The availability of river flow data in the Long River and very wide catchments are difficult to obtain, while river flow data are essential for planning waterworks. To predict the water flow in the catchment area requires a lot of hydrology coefficient, so it is very difficult to predict and obtain results that closer to the real conditions. This paper demonstrates that artificial neural network (ANN) could be used to predict the water flow. The ANN technique can be used to predict the incidence of water discharge that occurs in the Kapuas River based on rainfall and evaporation data. With the data available to do training on the artificial neural network model is obtained mean square error (MSE) 0.00007. The river flow predictions could be carried out after the training. The results showed differences in water discharge measurement and prediction of about 4%.

  7. Development west coast Taiwan: Redesign coastal area between Da’an River and Dajia River

    NARCIS (Netherlands)

    Van den Berg, B.; Eelkema, M.; Smith, M.; Van To, P.

    2006-01-01

    Master project report. In the year 2004 there was a flooding in an area between Da'an River and Dajia River in Taichung County, Taiwan. The flooding was caused by outlets which were clogged up, thus lacking the capacity to discharge the amount of rainwater that the typhoon caused into the sea. A

  8. An Evaluation of River Health for the Weihe River in Shaanxi Province, China

    Directory of Open Access Journals (Sweden)

    Jinxi Song

    2015-01-01

    Full Text Available Excessive socioeconomic activities in the Weihe River region have caused severe ecosystem degradation, and the call for the recovery and maintenance of the river health has drawn great attention. Based on the connotation of river health, previous research findings, and status quo of the Weihe River ecosystem, in this study, we developed a novel health evaluation index system to quantitatively determine the health of the Weihe River in Shaanxi Province. The river in the study area was divided into five reaches based on the five hydrological gauging stations, and appropriate evaluation indices for each river section were selected according to the ecological environmental functions of that section. A hybrid approach integrating analytic hierarchy process (AHP and a fuzzy synthetic evaluation method was applied to measure the river health. The results show that Linjiancun-Weijiabao reach and Weijiabao-Xianyang reach are in the “moderate” level of health and Lintong-Huaxian reach and downstream of Huaxian reach are in the “poor” health rating, whereas Xianyang-Lintong reach is in the “sick” rating. Moreover, the most sensitive factors were determined, respectively, for each reach from upper stream to lower stream in the study area.

  9. Canoeing the Murray River (Australia) as Environmental Education: A Tale of Two Rivers

    Science.gov (United States)

    Stewart, Alistair

    2004-01-01

    The Murray River, lying at the heart of Australia's largest catchment, is used extensively in outdoor education programs in south-eastern Australia. Since European settlement the river's ecological health has declined considerably due to activities such as damming for irrigation and clearing of native vegetation. Colonial notions of how the river…

  10. Molybdenum, vanadium, and uranium weathering in small mountainous rivers and rivers draining high-standing islands

    Science.gov (United States)

    Gardner, Christopher B.; Carey, Anne E.; Lyons, W. Berry; Goldsmith, Steven T.; McAdams, Brandon C.; Trierweiler, Annette M.

    2017-12-01

    Rivers draining high standing islands (HSIs) and small mountainous rivers (SMRs) are known to have extremely high sediment fluxes, and can also have high chemical weathering yields, which makes them potentially important contributors to the global riverine elemental flux to the ocean. This work reports on the riverine concentrations, ocean flux, and weathering yields of Molybdenum (Mo), Vanadium (V), and Uranium (U) in a large number of small but geochemically important rivers using 338 river samples from ten lithologically-diverse regions. These redox-sensitive elements are used extensively to infer paleo-redox conditions in the ocean, and Mo and V are also important rock-derived micronutrients used by microorganisms in nitrogen fixation. Unlike in large river systems, in which dissolved Mo has been attributed predominately to pyrite dissolution, Mo concentrations in these rivers did not correlate with sulfate concentrations. V was found to correlate strongly with Si in terrains dominated by silicate rocks, but this trend was not observed in primarily sedimentary regions. Many rivers exhibited much higher V/Si ratios than larger rivers, and rivers draining young Quaternary volcanic rocks in Nicaragua had much higher dissolved V concentrations (mean = 1306 nM) than previously-studied rivers. U concentrations were generally well below the global average with the exception of rivers draining primarily sedimentary lithologies containing carbonates and shales. Fluxes of U and Mo from igneous terrains of intermediate composition are lower than the global average, while fluxes of V from these regions are higher, and up to two orders of magnitude higher in the Nicaragua rivers. Weathering yields of Mo and V in most regions are above the global mean, despite lower than average concentrations measured in some of those systems, indicating that the chemical weathering of these elements are higher in these SMR watersheds than larger drainages. In regions of active boundaries

  11. Field intercomparison of channel master ADCP with RiverSonde Radar for measuring river discharge

    Science.gov (United States)

    Spain, P.; Marsden, R.; Barrick, D.; Teague, C.; Ruhl, C.

    2005-01-01

    The RiverSonde radar makes non-contact measurement of a horizontal swath of surface velocity across a river section. This radar, which has worked successfully at several rivers in the Western USA, has shown encouraging correlation with simultaneous measurements of average currents at one level recorded by an acoustic travel-time system. This work reports a field study intercomparing data sets from a 600 kHz Channel Master ADCP with the RiverSonde radar. The primary goal was to begin to explore the robustness of the radar data as a reliable index of discharge. This site Is at Three Mile Slough in Northern California, USA. The larger intent of the work is to examine variability in space and time of the radar's surface currents compared with subsurface flows across the river section. Here we examine data from a couple of periods with strong winds. ?? 2005 IEEE.

  12. River and Reservoir Operations Model, Truckee River basin, California and Nevada, 1998

    Science.gov (United States)

    Berris, Steven N.; Hess, Glen W.; Bohman, Larry R.

    2001-01-01

    The demand for all uses of water in the Truckee River Basin, California and Nevada, commonly is greater than can be supplied. Storage reservoirs in the system have a maximum effective total capacity equivalent to less than two years of average river flows, so longer-term droughts can result in substantial water-supply shortages for irrigation and municipal users and may stress fish and wildlife ecosystems. Title II of Public Law (P.L.) 101-618, the Truckee?Carson?Pyramid Lake Water Rights Settlement Act of 1990, provides a foundation for negotiating and developing operating criteria, known as the Truckee River Operating Agreement (TROA), to balance interstate and interbasin allocation of water rights among the many interests competing for water from the Truckee River. In addition to TROA, the Truckee River Water Quality Settlement Agreement (WQSA), signed in 1996, provides for acquisition of water rights to resolve water-quality problems during low flows along the Truckee River in Nevada. Efficient execution of many of the planning, management, or environmental assessment requirements of TROA and WQSA will require detailed water-resources data coupled with sound analytical tools. Analytical modeling tools constructed and evaluated with such data could help assess effects of alternative operational scenarios related to reservoir and river operations, water-rights transfers, and changes in irrigation practices. The Truckee?Carson Program of the U.S. Geological Survey, to support U.S. Department of the Interior implementation of P.L. 101-618, is developing a modeling system to support efficient water-resources planning, management, and allocation. The daily operations model documented herein is a part of the modeling system that includes a database management program, a graphical user interface program, and a program with modules that simulate river/reservoir operations and a variety of hydrologic processes. The operations module is capable of simulating lake

  13. Hydrology and morphology of two river mouth regions (temperate Vistula Delta and subtropical Red River Delta

    Directory of Open Access Journals (Sweden)

    Zbigniew Pruszak

    2005-09-01

    Full Text Available The paper presents a comparative analysis of two different river mouths from two different geographical zones (subtropical and temperate climatic regions. One is the multi-branch and multi-spit mouth of the Red River on the Gulf of Tonkin (Vietnam, the other is the smaller delta of the river Vistula on a bay of the Baltic Sea (Poland. The analysis focuses on the similarities and differences in the hydrodynamics between these estuaries and the adjacent coastal zones, the features of sediment transport, and the long-term morphodynamics of the river outlets. Salinity and water level are also discussed, the latter also in the context of the anticipated global effect of accelerated sea level rise. The analysis shows that the climatic and environmental conditions associated with geographical zones give rise to fundamental differences in the generation and dynamic evolution of the river mouths.

  14. South Fork Clearwater River Habitat Enhancement, Crooked and Red Rivers : Annual Report, 1989.

    Energy Technology Data Exchange (ETDEWEB)

    Baer, William H.

    1990-01-01

    In 1983, the Nez Perce National Forest and the Bonneville Power Administration entered into an interagency agreement to enhance and improve habitat for two anadromous fish species, spring chinook salmon (Oncorhynchus tshawyscha) and summer steelhead trout (Onchorhyncus mykiss), in the South Fork Clearwater River tributaries. The South Fork Clearwater River was dammed in 1927 for hydroelectric development. Anadromous fish runs were virtually eliminated until the dam was removed in 1962. To complicate the problem, upstream spawning and rearing habitats were severely impacted by dredge and hydraulic mining, road building, timber harvest, and over-grazing. Fish habitat improvement projects under the above contract are being carried out in two major tributaries to the South Fork Clearwater River. Both the Red River and the Crooked River projects began in 1983 and will be completed in 1990. 12 figures., 1 tab.

  15. Characterizing seston in the Penobscot River Estuary.

    Science.gov (United States)

    Meseck, Shannon L; Li, Yaqin; Sunila, Inke; Dixon, Mark; Clark, Paul; Lipsky, Christine; Stevens, Justin R; Music, Paul; Wikfors, Gary H

    2017-10-01

    The Penobscot River Estuary is an important system for diadromous fish in the Northeast United States of American (USA), in part because it is home to the largest remnant population of Atlantic salmon, Salmo salar, in the country. Little is known about the chemical and biological characteristics of seston in the Penobscot River Estuary. This study used estuarine transects to characterize the seston during the spring when river discharge is high and diadromous fish migration peaks in the Penobscot River Estuary. To characterize the seston, samples were taken in spring 2015 for phytoplankton identification, total suspended matter (TSM), percent organic TSM, chlorophyll a, particle size (2 μm-180 μm), particulate carbon and nitrogen concentrations, and stable carbon and nitrogen isotopes. The estuarine profiles indicate that TSM behaved non-conservatively with a net gain in the estuary. As phytoplankton constituted only 1/1000 of the particles, the non-conservative behavior of TSM observed in the estuary was most likely not attributable to phytoplankton. Particulate carbon and nitrogen ratios and stable isotope signals indicate a strong terrestrial, allochthonous signal. The seston in the Penobscot River Estuary was dominated by non-detrital particles. During a short, two-week time period, Heterosigma akashiwo, a phytoplankton species toxic to finfish, also was detected in the estuary. A limited number of fish samples, taken after the 2015 Penobscot River Estuary bloom of H. akashiwo, indicated frequent pathological gill damage. The composition of seston, along with ichthyotoxic algae, suggest the need for further research into possible effects upon resident and migratory fish in the Penobscot River Estuary. Published by Elsevier Ltd.

  16. Suitability Evaluation on River Bank Filtration of the Second Songhua River, China

    Science.gov (United States)

    Wang, Lixue; Ye, Xueyan; Du, Xinqiang

    2016-04-01

    The Second Songhua River is the biggest river with the most economic value in Jilin Province, China. In recent years, with the rapid development of economy, water resources and water environment problem is getting prominent, including surface water pollution and over exploitation of groundwater resources, etc. By means of bank filtration, the Second Songhua River basin might realize the combined utilization of regional groundwater and surface water, and thus has important significance for the guarantee of water demand for industrial and agricultural production planning in the basin. The following steps were adopted to evaluate the suitability of bank filtration nearby the Scond Songhua River : Firstly, in order to focus on the most possible area, the evaluation area was divided based on the aspects of natural geographical conditions and hydraulic connection extent between river water and groundwater. Second, the main suitability indexes including water quantity, water quality, interaction intensity between surface water and groundwater, and the exploitation condition of groundwater resource, and nine sub-indexes including hydraulic conductivity, aquifer thickness, river runoff, the status of groundwater quality, the status of surface water quality, groundwater hydraulic gradient, possible influence zone width of surface water under the condition of groundwater exploitation, permeability of riverbed layer and groundwater depth were proposed to establish an evaluation index system for the suitability of river bank filtration. Thirdly, Combined with the natural geography, geology and hydrogeology conditions of the Second Songhua River basin, the ArcGIS technology is used to complete the evaluation of the various indicators. According to the weighted sum of each index, the suitability of river bank filtration in the study area is divided into five grades. The evaluation index system and evaluation method established in this article are applicable to the Second Songhua

  17. Glacier fluctuation using Satellite Data in Beas basin, 1972–2006 ...

    Indian Academy of Sciences (India)

    imbalance. 1. Introduction. The Indian Himalaya comprises of approximately. 9600 glaciers (Raina and Srivastava 2008). The snow and ice melt water from these glaciers form a unique freshwater reservoir. Numerous perennial rivers such as Indus, Brahmaputra and to a mod- est level, the river Ganga, depend on the melt.

  18. RiverHeath: Neighborhood Loop Geothermal Exchange System

    Energy Technology Data Exchange (ETDEWEB)

    Geall, Mark [RiverHeath LLC, Appleton, WI (United States)

    2016-07-11

    The goal of the RiverHeath project is to develop a geothermal exchange system at lower capital infrastructure cost than current geothermal exchange systems. The RiverHeath system features an innovative design that incorporates use of the adjacent river through river-based heat exchange plates. The flowing water provides a tremendous amount of heat transfer. As a result, the installation cost of this geothermal exchange system is lower than more traditional vertical bore systems. Many urban areas are located along rivers and other waterways. RiverHeath will serve as a template for other projects adjacent to the water.

  19. Smartphone for measuring river discharge

    Science.gov (United States)

    Peña-Haro, Salvador; Lüthi, Beat; Philippe, Thomas

    2015-04-01

    Smartphones have become powerful and have extended their capacities including different types of sensors. These capabilities make them very interesting for its applications in water management. We have developed a new mobile device application for open-channel flow measurements. This app can be used to determine the flow in e.g. rivers, artificial channels, irrigation ditches, furrows, etc. The smartphone app computes the runoff by analysing a few seconds of a movie that is recorded using the smartphone camera. The runoff is calculated from the estimated water level, surface velocity and from prior knowledge on the channel geometry. The water level is determined by the separation line of image segments with and without optical flow. Via calibration of the smartphone camera position this separation line is mapped to a water level. The surface velocity is calculated using a modified method of the standard Particle Image Velocimetry method. Among the key characteristics of the method is the fact that no tracer particles are needed. There are two flavours of the app. In the first one, all the measurements are taken using the available sensors in the mobile device and all the calculations are made making only use of the device. Three results are given back: the water level, the average surface velocity and discharge. This information can be sent via SMS. In the second one, the movie is send to a central computer where more detailed calculations are made, like fine camera calibration, camera stabilization tuning, definition of the region of interest, the sub-windows for the velocity analysis can be changed, different algorithms can be chosen, etc. It also generates more detailed results. Using smartphones, measurements can be made at much lower cost, since there is no need of permanent installations, which also makes it possible to take measurements in any place.

  20. Columbia River impact evaluation plan

    Energy Technology Data Exchange (ETDEWEB)

    1993-06-01

    As a result of past practices, four areas of the Hanford Site (the 100, 200, 300, and 1100 Areas) have been included on the US Environmental Protection Agency`s (EPA`s) National Priorities List (NPL) under the Comprehensive Environmental Response, Compensation, and Liability Act of 1980. To accomplish the timely cleanup of the past-practice units, the Hanford Federal Facility Agreement and Consent Order (Tri-Party Agreement), was signed by the Washington State Department of Ecology (Ecology), EPA, and the US Department of Energy (DOE). To support the Tri-Party Agreement, milestones were adopted. These milestones represent the actions needed to ensure acceptable progress toward Hanford Site compliance with CERCLA, RCRA, and the Washington State Hazardous Waste Management Act of 1976. This report was prepared to fulfill the requirement of Tri-Party Agreement Milestone M-30-02, which requires a plan to determine cumulative health and environmental impacts to the Columbia River. This plan supplements the CERCLA remedial investigations/feasibility studies (RI/FS) and RCRA facility investigations/corrective measures studies (RFI/CMSs) that will be undertaken in the 100 Area. To support the plan development process, existing information was reviewed and a preliminary impact evaluation based on this information was performed. The purpose of the preliminary impact evaluation was to assess the adequacy of existing data and proposed data collection activities. Based on the results of the evaluation, a plan is proposed to collect additional data or make changes to existing or proposed data collection activities.

  1. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ; KIRKBRIDE RA; HOHL TM; EMPEY PA; WELLS MN

    2009-09-15

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, ORP is responsible for the retrieval, treatment, and disposal of approximately 57 million gallons 1 of radioactive waste contained in the Hanford Site waste tanks and closure2 of all the tanks and associated facilities. The previous revision of the System Plan was issued in May 2008. ORP has made a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. ORP has contracts in place to implement the strategy for completion of the mission and establish the capability to complete the overall mission. The current strategl involves a number of interrelated activities. ORP will reduce risk to the environment posed by tank wastes by the following: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) and delivering the waste to the Waste Treatment and Immobilization Plant (WTP). (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) fraction contained in the tank farms. About one-third of the low-activity waste (LAW) fraction separated from the HLW fraction in the WTP will be immobilized in the WTP LAW Vitrification Facility. (3) Developing and deploying supplemental treatment capability assumed to be a second LAW vitrification facility that can safely treat about two-thirds of the LAW contained in the tank farms. (4) Developing and deploying supplemental pretreatment capability currently assumed to be an Aluminum Removal Facility (ARF) using a lithium hydrotalcite process to mitigate sodium management issues. (5) Developing and deploying treatment and packaging capability for contact-handled transuranic (CH-TRU) tank waste for possible shipment to and

  2. RIVER PROTECTION PROJECT SYSTEM PLAN

    Energy Technology Data Exchange (ETDEWEB)

    CERTA PJ

    2008-07-10

    The U.S. Department of Energy (DOE), Office of River Protection (ORP) manages the River Protection Project (RPP). The RPP mission is to retrieve and treat Hanford's tank waste and close the tank farms to protect the Columbia River. As a result, the ORP is responsible for the retrieval, treatment, and disposal of the approximately 57 million gallons of radioactive waste contained in the Hanford Site waste tanks and closure of all the tanks and associated facilities. The previous revision of the System Plan was issued in September 2003. ORP has approved a number of changes to the tank waste treatment strategy and plans since the last revision of this document, and additional changes are under consideration. The ORP has established contracts to implement this strategy to establish a basic capability to complete the overall mission. The current strategy for completion of the mission uses a number of interrelated activities. The ORP will reduce risk to the environment posed by tank wastes by: (1) Retrieving the waste from the single-shell tanks (SST) to double-shell tanks (DST) for treatment and disposal; (2) Constructing and operating the WTP, which will safely treat all of the high-level waste (HLW) and about half of the low-activity waste (LAW) contained in the tank farms, and maximizing its capability and capacity; (3) Developing and deploying supplemental treatment capability or a second WTP LAW Facility that can safely treat about half of the LAW contained in the tank farms; (4) Developing and deploying treatment and packaging capability for transuranic (TRU) tank waste for shipment to and disposal at the Waste Isolation Pilot Plant (WIPP); (5) Deploying interim storage capacity for the immobilized HLW and shipping that waste to Yucca Mountain for disposal; (6) Operating the Integrated Disposal Facility for the disposal of immobilized LAW, along with the associated secondary waste, (7) Closing the SST and DST tank farms, ancillary facilities, and al1 waste

  3. Resilience scales of a dammed tropical river

    Science.gov (United States)

    Calamita, Elisa; Schmid, Martin; Wehrli, Bernhard

    2017-04-01

    Artificial river impoundments disrupt the seasonality and dynamics of thermal, chemical, morphological and ecological regimes in river systems. These alterations affect the aquatic ecosystems in space and time and specifically modify the seasonality and the longitudinal gradients of important biogeochemical processes. Resilience of river systems to anthropogenic stressors enables their recovery along the flow path; however little is known about the longitudinal distance that rivers need to partially restore their physical, chemical and biological integrity. In this study, the concept of a "resilience scale" will be explored for different water quality parameters downstream of Kariba dam, the largest artificial lake in the Zambezi basin (South-East Africa). The goal of this project is to develop a modelling framework to investigate and quantify the impact of large dams on downstream water quality in tropical context. In particular, we aim to assess the degree of reversibility of the main downstream alterations (temperature, oxygen, nutrients) and consequently the quantification of their longitudinal extent. Coupling in-situ measurements with hydraulic and hydrological parameters such as travel times, will allow us to define a physically-based parametrization of the different resilience scales for tropical rivers. The results will be used for improving future dam management at the local scale and assessing the ecological impact of planned dams at the catchment scale.

  4. ANTHROPOGENIC LOAD ON RIVERS OF URBAN AREAS

    Directory of Open Access Journals (Sweden)

    Kurochkina Valentina Aleksandrovna

    2016-08-01

    Full Text Available The increasing speed of urbanization and population growth lead to the increasing anthropogenic load on water bodies. The urbanization processes in Russia are more intensive than in other countries. The dense population and great industrial potential lead to the fact that the urbanized territories become the main sources of water pollution. That’s why the environmental control of the state of water objects is needed. In the article the authors study the problem of anthropogenic load impact on river hydraulics processes and on the properties of river sediments that determine river channels evolution and general ecological state of water bodies. The interrelation between ecological state of water bodies, the quality of water in it and the level of contamination with sediments was determined. It is established that the conditions of long-term aquatic life as a whole and of water quality in particular depend on the contamination level with sediments. The author proposes a method of estimation of anthropogenic load on rivers. The paper analyses the calculation results of the value of anthropogenic load on different rivers of Russia.

  5. Tidal controls on river delta morphology

    Science.gov (United States)

    Hoitink, A. J. F.; Wang, Z. B.; Vermeulen, B.; Huismans, Y.; Kästner, K.

    2017-09-01

    River delta degradation has been caused by extraction of natural resources, sediment retention by reservoirs, and sea-level rise. Despite global concerns about these issues, human activity in the world’s largest deltas intensifies. Harbour development, construction of flood defences, sand mining and land reclamation emerge as key contemporary factors that exert an impact on delta morphology. Tides interacting with river discharge can play a crucial role in the morphodynamic development of deltas under pressure. Emerging insights into tidal controls on river delta morphology suggest that--despite the active morphodynamics in tidal channels and mouth bar regions--tidal motion acts to stabilize delta morphology at the landscape scale under the condition that sediment import during low flows largely balances sediment export during high flows. Distributary channels subject to tides show lower migration rates and are less easily flooded by the river because of opposing non-linear interactions between river discharge and the tide. These interactions lead to flow changes within channels, and a more uniform distribution of discharge across channels. Sediment depletion and rigorous human interventions in deltas, including storm surge defence works, disrupt the dynamic morphological equilibrium and can lead to erosion and severe scour at the channel bed, even decades after an intervention.

  6. Evaluation of kinetic energy in flowing rivers

    Energy Technology Data Exchange (ETDEWEB)

    Faure, T. [National Research Council of Canada, Ottawa, ON (Canada). Canadian Hydraulics Centre

    2008-07-01

    New methods of evaluating the kinetic energy in rivers were discussed. Developed by the National Research Council's Canadian Hydraulics Centre, the numerical models were designed to generate hydrographs of river flow from dams; accommodate power density anomalies caused by the presence of islands in a river; and assess mean kinetic power rates. This presentation provided details of a simulation of 6 turbines located in close proximity to each other. The model was used to calculate velocity fields downstream of the turbines as well as changes in water surface elevation due to power production by the 6 75 kW turbines. Turbine power extraction and kinetic power in the upstream cross-section was assessed. The model showed that the turbines extracted 9 per cent of the river's 17,000 kW of estimated energy potential. The turbines were modelled by considering the porosity of the numerical elements at the location of the turbine and extracting known quantities of energy from the flow. The model was also used to calculate new hydrodynamics of the whole region with the turbines in place by assuming that energy was extracted over the entire depth of the location. The presentation included detailed charts of rivers modelled during the study. tabs., figs.

  7. Effects of human activities on the ecological processes of river biofilms in a highly urbanized river

    Science.gov (United States)

    Hung, R.; Li, M.

    2013-12-01

    Many anthropogenic disturbances and their effects of aquatic ecosystem are difficult to quantify in urbanized rivers. In past, specific taxa analysis of community structure was a common approach in river health monitoring studies. However, it is still difficult to understand stream ecosystem integrity without considering ecosystem processes. The complex species composition and metabolism of a river biofilm have the capacity to interact and/or modulate their surrounding environment. Because of their short life cycles, species richness, and worldwide distribution, structure and function of river biofilm communities are sensitive to change in environmental conditions. Therefore, biofilms are widely used as early warning systems of water pollution for water quality monitoring studies. In this study, we used river biofilms as a bioindicator by examining their extracellular enzyme activities and photosynthesis efficiency to understand human activities on the ecological processes of river ecosystem in a highly urbanized river. We sampled four sites along the Keelung River, Taiwan, based on different intensities of anthropogenic disturbances including water pollution index, population densities, land use types and types of stream habitats. Two study sites are heavily influenced by human activities and the others are not. The activities of extracellular enzymes within the biofilm play an important function for organic matter decomposition and nutrient cycling. We measured seven extracellular enzyme activities (β-d-glucosidase, phosphatase, leucine-aminopeptidase, sulfatase, peroxidase, polyphenol oxidase, and esterase) to examine specific enzyme activity changes at four study sites monthly. In addition, relative proportion of each extracellular enzyme activity on total enzyme activities was calculated in order to examine the relationship between functional biofilm profiles and different urban intensities. Among four study sites, leucine-aminopeptidase and esterase

  8. Removal of river embankments and the modelled effects on river-floodplain hydrodynamics

    Science.gov (United States)

    Clilverd, Hannah; Thompson, Julian; Heppell, Kate; Sayer, Carl; Axmacher, Jan

    2015-04-01

    The channelization and embankment of rivers has led to major ecological degradation of aquatic habitats worldwide. River restoration, which often includes the removal of previously constructed barriers between a river and its floodplain, is now being widely used to create favourable hydrological conditions for target species or processes. However the effects of river restoration on hydraulic and hydrological processes are complex, and are often difficult to determine due to the infrequency of long-term monitoring programmes before and after restoration works. To examine the hydrological impacts of embankment removal under a variety of possible hydrological conditions, we developed coupled hydrological/hydraulic models of pre-embankment and post-embankment conditions at a wet grassland meadow in Norfolk, UK using the MIKE-SHE/MIKE 11 system. Groundwater hydrology and climate were monitored between 2007 and 2010 with river inflows being provided from an upstream gauging station. The embanked model was calibrated and validated with observed groundwater data for two consecutive 12-month periods, after which the restored topography was applied to the model and validated for a subsequent 12-month period. The restored model was then run for the same period as the embanked model (i.e. with the same river inflow, precipitation, and potential evapotranspiration data) to remove interannual climate variability and enable a direct comparison between models. Modelled groundwater levels compared well with piezometer observations and reproduced the observed rapid groundwater response to high magnitude rainfall and river flow events. Removal of the embankments resulted in frequent localised flooding at the river edge, widespread floodplain inundation at flows greater than 1.9 m3 sec-1, as well as higher groundwater levels and greater subsurface storage. Restoration had only a minor effect on flood peak attenuation (maximum 5% flood peak reduction), likely due to the small size of

  9. Navigation Conditions at Gray's Landing Locks and Dam, Monongahela River; Hydraulic Model Investigation

    National Research Council Canada - National Science Library

    Wooley, Ronald

    1998-01-01

    The Monongahela River (Figure 1) is formed by the confluence of the Tygart Valley and West Fork Rivers at Fairmont, WV, and flows in a northerly direction joining with the Allegheny River at Pittsburgh, PA, to form the Ohio River...

  10. Coherence between coastal and river flooding along the California coast

    Science.gov (United States)

    Odigie, Kingsley O.; Warrick, Jonathan

    2017-01-01

    Water levels around river mouths are intrinsically determined by sea level and river discharge. If storm-associated coastal water-level anomalies coincide with extreme river discharge, landscapes near river mouths will be flooded by the hydrodynamic interactions of these two water masses. Unfortunately, the temporal relationships between ocean and river water masses are not well understood. The coherence between extreme river discharge and coastal water levels at six California river mouths across different climatic and geographic regions was examined. Data from river gauges, wave buoys, and tide gauges from 2007 to 2014 were integrated to investigate the relationships between extreme river discharge and coastal water levels near the mouths of the Eel, Russian, San Lorenzo, Ventura, Arroyo Trabuco, and San Diego rivers. Results indicate that mean and extreme coastal water levels during extreme river discharge are significantly higher compared with background conditions. Elevated coastal water levels result from the combination of nontidal residuals (NTRs) and wave setups. Mean and extreme (>99th percentile of observations) NTRs are 3–20 cm and ∼30 cm higher during extreme river discharge conditions, respectively. Mean and extreme wave setups are up to 40 cm and ∼20–90 cm higher during extreme river discharge than typical conditions, respectively. These water-level anomalies were generally greatest for the northern rivers and least for the southern rivers. Time-series comparisons suggest that increases in NTRs are largely coherent with extreme river discharge, owing to the low atmospheric pressure systems associated with storms. The potential flooding risks of the concurrent timing of these water masses are tempered by the mixed, semidiurnal tides of the region that have amplitudes of 2–2.5 m. In summary, flooding hazard assessments for floodplains near California river mouths for current or future conditions with sea-level rise should include the temporal

  11. Delimitation of permanent protected areas of rivers in Brazil

    Science.gov (United States)

    Leonardi, Silvia S.; Namikawa, Laércio M.; de F. Oliveira, João. R.; Rosim, Sergio

    2014-10-01

    This paper presents a methodology to determine the permanent protected areas (PPA) of the the riverbanks. The amount of protected area depends on the river width and the size of each property which have a river running through or by it, as stated in the Brazilian forest code law. The rules are: 30 meters for rivers up to 10 meters wide, 50m for rivers 10 to 50m wide, 100m for rivers 50 to 200m wide, 200m for rivers 200 to 600m wide, and 500m, to rivers wider than 600m. The steps to determine the PPA buffer along the river are (1) construction of the triangular grid (TIN) that constitutes the basis for the calculation of the central axis of the river; (2) definition of the points representing the central axis of the river, called skeletonization; (3) definition of the river width; (4) calculation of the buffer for each river segment. PPA is defined by overlaying the river protected area polygon with the property polygon. A PPA area of a property can be reduced according to its size and according to public improvements like roads, permanent protected areas, for example. At the end the area to be preserved in a property is delimited.

  12. Anthropogenic Influence on the Dynamics of the River Lamprey Lampetra fluviatilis Landings in the River Daugava Basin

    Science.gov (United States)

    Birzaks, Janis; Abersons, Kaspars

    2011-01-01

    The construction of the Daugava hydro power station (HPS) cascade has significantly transformed Latvia's largest river the Daugava, reducing its importance in the natural reproduction of anadromous fish species. Currently in Latvia, as well as in other Baltic Sea countries, the river lamprey catch is decreasing, whereas the landings in the river Daugava have tended to increase. The dynamics of the river lamprey landings show the possible redistribution of lamprey stocks between the rivers Gauja and the Daugava. Possibly, this is a result of anthropogenic influence and changes in the river lamprey resource management may be necessary in the future.

  13. Floodplain methylmercury biomagnification factor higher than that of the contiguous river (South River, Virginia USA)

    Energy Technology Data Exchange (ETDEWEB)

    Newman, Michael C., E-mail: newman@vims.edu [College of William and Mary - VIMS, P.O. Box 1346, Rt. 1208 Greate Rd., Gloucester Point, VA 23062 (United States); Xu Xiaoyu, E-mail: xiaoyu@vims.edu [College of William and Mary - VIMS, P.O. Box 1346, Rt. 1208 Greate Rd., Gloucester Point, VA 23062 (United States); Condon, Anne, E-mail: anne_condon@fws.gov [U.S. Fish and Wildlife, 6669 Short Lane, Gloucester, VA 23061 (United States); Liang Lian, E-mail: liang@cebam.net [Cebam Analytical, Inc., 18804 North Creek Parkway, Suite 110, Bothell, WA 98011 (United States)

    2011-10-15

    Mercury biomagnification on the South River floodplain (Virginia, USA) was modeled at two locations along a river reach previously modeled for methylmercury movement through the aquatic trophic web. This provided an opportunity to compare biomagnification in adjoining trophic webs. Like the aquatic modeling results, methylmercury-based models provided better prediction than those for total mercury. Total mercury Food Web Magnification Factors (FWMF, fold per trophic level) for the two locations were 4.9 and 9.5. Methylmercury FWMF for the floodplain locations were higher (9.3 and 25.1) than that of the adjacent river (4.6). Previous speculation was not resolved regarding whether the high mercury concentrations observed in floodplain birds was materially influenced by river prey consumption by riparian spiders and subsequent spider movement into the trophic web of the adjacent floodplains. Results were consistent with a gradual methylmercury concentration increase from contaminated floodplain soil, to arthropod prey, and finally, to avian predators. - Highlights: > First comparison of methylmercury biomagnification in adjacent river/land food webs. > Methylmercury increased more rapidly in the terrestrial, than the aquatic, food web. > Methylmercury increased gradually from soil, to prey, and, to avian predators. - Higher methylmercury biomagnification on South River floodplain than the associated river likely explain high mercury in floodplain birds.

  14. Seasonal variability of Crvena river water mineralization

    Directory of Open Access Journals (Sweden)

    Manojlović Predrag

    2010-01-01

    Full Text Available The mineralization of water and its content in Crvena River so far have not been studied. Water sampling was conducted from April 2008 - May 2009. Total mineralization is relatively low, which is consistent with the dominant lithological structure (Permian red sandstone. Dry residue contains Ca2+ ion, with the increased participation of SiO2. During the observational period it is clearly expressed seasonal effect. It is reflected not in the direct but the indirect impact. Based on the ratio of individual ions a model is determined for estimation of water flow at the confluence of the Crvena River in Nisava River. It could be applied to other drainage basins that have not been studied so far.

  15. Smoky River coal flood risk mapping study

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-06-01

    The Canada-Alberta Flood Damage Reduction Program (FDRP) is designed to reduce flood damage by identifying areas susceptible to flooding and by encouraging application of suitable land use planning, zoning, and flood preparedness and proofing. The purpose of this study is to define flood risk and floodway limits along the Smoky River near the former Smoky River Coal (SRC) plant. Alberta Energy has been responsible for the site since the mine and plant closed in 2000. The study describes flooding history, available data, features of the river and valley, calculation of flood levels, and floodway determination, and includes flood risk maps. The HEC-RAS program is used for the calculations. The flood risk area was calculated using the 1:100 year return period flood as the hydrological event. 7 refs., 11 figs., 7 tabs., 3 apps.

  16. River plastic emissions to the world's oceans

    Science.gov (United States)

    Lebreton, Laurent C. M.; van der Zwet, Joost; Damsteeg, Jan-Willem; Slat, Boyan; Andrady, Anthony; Reisser, Julia

    2017-06-01

    Plastics in the marine environment have become a major concern because of their persistence at sea, and adverse consequences to marine life and potentially human health. Implementing mitigation strategies requires an understanding and quantification of marine plastic sources, taking spatial and temporal variability into account. Here we present a global model of plastic inputs from rivers into oceans based on waste management, population density and hydrological information. Our model is calibrated against measurements available in the literature. We estimate that between 1.15 and 2.41 million tonnes of plastic waste currently enters the ocean every year from rivers, with over 74% of emissions occurring between May and October. The top 20 polluting rivers, mostly located in Asia, account for 67% of the global total. The findings of this study provide baseline data for ocean plastic mass balance exercises, and assist in prioritizing future plastic debris monitoring and mitigation strategies.

  17. ICHTHYOFAUNA OF A PART OF SAVA RIVER

    Directory of Open Access Journals (Sweden)

    Dobrila Habeković

    1997-07-01

    Full Text Available Based on a personal research from 1991-1994 the ichthyofauna structure of the part of the Sava river upstream from Zagreb on the section from Podsused to Gradna mouth is presented. The data are being compared with the results of the research of this part of the Sava river before constructing the Krško nuclear power plant. The ichthyological samples were taken seasonally, on various water levels and temperatures of the Sava river. A qualitative and quantitive structure of the fish communities was identified (Tabels 1 to 7. The researched area is populated by fish of the transitional-plain type of the open waters, which means it belongs to the typical barbel region with all the related fish species. The most numerous is the Cyprinidae family, dominated by the chub species (Leuciscus cephalus L.. Around thirty species and subspecies of fish and Cyclostomata populates the area.

  18. Flood Forecasting in River System Using ANFIS

    Science.gov (United States)

    Ullah, Nazrin; Choudhury, P.

    2010-10-01

    The aim of the present study is to investigate applicability of artificial intelligence techniques such as ANFIS (Adaptive Neuro-Fuzzy Inference System) in forecasting flood flow in a river system. The proposed technique combines the learning ability of neural network with the transparent linguistic representation of fuzzy system. The technique is applied to forecast discharge at a downstream station using flow information at various upstream stations. A total of three years data has been selected for the implementation of this model. ANFIS models with various input structures and membership functions are constructed, trained and tested to evaluate efficiency of the models. Statistical indices such as Root Mean Square Error (RMSE), Correlation Coefficient (CORR) and Coefficient of Efficiency (CE) are used to evaluate performance of the ANFIS models in forecasting river flood. The values of the indices show that ANFIS model can accurately and reliably be used to forecast flood in a river system.

  19. [Nutrients Input Characteristics of the Yangtze River and Wangyu River During the "Water Transfers on Lake Taihu from the Yangtze River"].

    Science.gov (United States)

    Pan, Xiao-xue; Ma, Ying-qun; Qin, Yan-wen; Zou, Hua

    2015-08-01

    Overall 20 surface water samples were collected from the Yangtze River, the Wangyu River and the Gonghu Bay (Lake Taihu) to clarify the pollution characteristics of nitrogen and phosphorus during 2 sample stages of "Water Transfers on Lake Taihu from the Yangtze River" in August and December of 2013 respectively. The results showed that the mass concentrations of NO2- -N, NO3- -N, NH4+ -N and TN in the Gonghu Bay were lower than those of the Yangtze River and Wangyu River during the 2 water transfer processes. However, there was higher level of DON content in the Gonghu Bay than that of the Yangtze River and Wangyu River. The percentages of various N species showed that NO3- -N was the major N species in the Yangtze River and Wangyu River during the 2 water transfer processes. TP contents in samples collected from the Yangtze River displayed a constant trend compared with the Wangyu River. However, the percentages of various P species were different with each other during the 2 water transfer processes. Mass concentrations of DON and TP in surface water in August were higher than those in December and the contents of NO3- -N and TDP were lower in August than those in December. In general, NO3- -N and TPP were the main N and P species in Wangyu River from the Yangtze River. NO3- -N, PO4(3-) -P and TPP were the main N and P species in Gonghu Bay from Wangyu River during the 2 water transfer processes.

  20. Evaluate Status of Pacific Lamprey in the Clearwater River and Salmon River Drainages, Idaho, 2009 Technical Report.

    Energy Technology Data Exchange (ETDEWEB)

    Cochnauer, Tim; Claire, Christopher [Idaho Department of Fish and Game

    2009-05-07

    Pacific lamprey Lampetra tridentata have received little attention in fishery science until recently, even though abundance has declined significantly along with other anadromous fish species in Idaho. Pacific lamprey in Idaho have to navigate over eight lower Snake River and Columbia River hydroelectric facilities for migration downstream as juveniles to the Pacific Ocean and again as adults migrating upstream to their freshwater spawning grounds in Idaho. The number of adult Pacific lamprey annually entering the Snake River basin at Ice Harbor Dam has declined from an average of over 18,000 during 1962-1969 to fewer than 600 during 1998-2006. Based on potential accessible streams and adult escapement over Lower Granite Dam on the lower Snake River, we estimate that no more than 200 Pacific lamprey adult spawners annually utilize the Clearwater River drainage in Idaho for spawning. We utilized electrofishing in 2000-2006 to capture, enumerate, and obtain biological information regarding rearing Pacific lamprey ammocoetes and macropthalmia to determine the distribution and status of the species in the Clearwater River drainage, Idaho. Present distribution in the Clearwater River drainage is limited to the lower sections of the Lochsa and Selway rivers, the Middle Fork Clearwater River, the mainstem Clearwater River, the South Fork Clearwater River, and the lower 7.5 km of the Red River. In 2006, younger age classes were absent from the Red River.

  1. Morphodynamic river processes and techniques for assessment of channel evolution in Alpine gravel bed rivers

    Science.gov (United States)

    Formann, E.; Habersack, H. M.; Schober, St.

    2007-10-01

    Over the past 10 years many restoration projects have been undertaken in Austria, and river engineering measures such as spur dykes and longitudinal bank protection, which imposed fixed lateral boundaries on rivers, have been removed. The EU-Life Project "Auenverbund Obere Drau" has resulted in extensive restoration on the River Drau, aimed to improve the ecological integrity of the river ecosystem, to arrest riverbed degradation, and to ensure flood protection. An essential part of the restoration design involved the consideration of self-forming river processes, which led to new demands being imposed on river management. This paper illustrates how model complexity is adapted to the solution and evaluation of different aspects of river restoration problems in a specific case. Point-scale monitoring data were up-scaled to the whole investigation area by means of digital elevation models, and a scaling approach to the choice of model complexity was applied. Simple regime analysis methods and 1-D models are applicable to the evaluation of long-term and reach-scale restoration aims, and to the prediction of kilometre-scale processes (e.g. mean river bed aggradation or degradation, flood protection). 2-D models gave good results for the evaluation of hydraulic changes (e.g. transverse flow velocities, shear stresses, discharges at diffluences) for different morphological units at the local scale (100 m-10 m), and imposed an intermediate demand on calibration data and topographic survey. The study shows that complex 3-D numerical models combined with high resolution digital elevation models are necessary for detailed analysis of processes (1 m-0.01 m), but not for the evaluation of the restoration aims on the River Drau. In conclusion, model choice (complexity) will depend on both lower limits (determined by the complexity of processes to be analysed) and upper limits (field data quality and process understanding for numerical models).

  2. Sediment regime constraints on river restoration - An example from the lower Missouri river

    Science.gov (United States)

    Jacobson, R.B.; Blevins, D.W.; Bitner, C.J.

    2009-01-01

    Dammed rivers are subject to changes in their flow, water-quality, and sediment regimes. Each of these changes may contribute to diminished aquatic habitat quality and quantity. Of the three factors, an altered sediment regime is a particularly unyielding challenge on many dammed rivers. The magnitude of the challenge is illustrated on the Lower Missouri River, where the largest water storage system in North America has decreased the downriver suspended-sediment load to 0.2%–17% of pre-dam loads. In response to the altered sediment regime, the Lower Missouri River channel has incised as much as 3.5 m just downstream of Gavins Point Dam, although the bed has been stable to slightly aggrading at other locations farther downstream. Effects of channel engineering and commercial dredging are superimposed on the broad-scale adjustments to the altered sediment regime.The altered sediment regime and geomorphic adjustments constrain restoration and management opportunities. Incision and aggradation limit some objectives of flow-regime management: In incising river segments, ecologically desirable reconnection of the floodplain requires discharges that are beyond operational limits, whereas in aggrading river segments, small spring pulses may inundate or saturate low-lying farmlands. Lack of sediment in the incising river segment downstream of Gavins Point Dam also limits sustainable restoration of sand-bar habitat for bird species listed under the Endangered Species Act. Creation of new shallow-water habitat for native fishes involves taking sediment out of floodplain storage and reintroducing most or all of it to the river, raising concerns about increased sediment, nutrient, and contaminant loads. Calculations indicate that effects of individual restoration projects are small relative to background loads, but cumulative effects may depend on sequence and locations of projects. An understanding of current and historical sediment fluxes, and how they vary along the river

  3. Impacts of Colville River dynamics on river navigability near Nuiqsut, Alaska: 1955-present

    Science.gov (United States)

    Whitley, M. A.; Panda, S. K.; Prakash, A.; Brinkman, T. J.

    2016-12-01

    Climate-driven changes in river systems are challenging access to ecosystem services such as access to traditional hunting grounds and other subsistence food sources on the North Slope of Alaska. This work studies the dynamics of the Colville River and assesses the impacts on traditional harvest practices and subsistence travel of the Native community of Nuiqsut. Recent reports from Nuiqsut residents indicate accelerated changes in the environment, limiting river travel and their ability to harvest subsistence food. This study explores how channel migration, gravel bars, and bank erosion have evolved since the 1950s, and their impact on water depth and navigability. In an area of ice-rich permafrost, warmer summer temperatures exacerbate lateral bank erosion, resulting in river siltation. The study focuses on selected key areas south of Nuiqsut that have shown significant change in river geomorphology. Since 1955, some areas proximate to ice wedge exposures show channel migration in excess of 1 km. Panchromatic aerial photography acquired by US Geological Surveys in the mid 1950s, color infrared aerial photography from 1979 and 1982 acquired by the Alaska High Altitude Photography (AHAP) mission, and high resolution satellite images from Digital Globe, Inc. were used in this study. We mapped water, vegetation, and gravel/non-vegetated classes to identify risk areas for river navigability. River bathymetry was also mapped using a multispectral ratio-based water depth retrieval algorithm to identify problem sites for boat travel. Remote sensing products and analyses were validated with field data for mapping risk areas along the river. This study has the potential to be implemented on a larger scale for predictive mapping to aid river navigation. Findings from this study will provide insight whether recent changes are anomalies, or if they are part of a directional trend that will require local adaptation.

  4. Land protection plan : Bear River Watershed Conservation Area

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The U.S. Fish and Wildlife Service is establishing a conservation area for the Bear River watershed in Idaho, Utah, and Wyoming. The Bear River Watershed...

  5. Russian River Ice Thickness and Duration, Version 1

    Data.gov (United States)

    National Aeronautics and Space Administration — This data set consists of river ice thickness measurements, and beginning and ending dates for river freeze-up events from fifty stations in northern Russia. The...

  6. Simulating the discharge of the Mandovi River, Goa

    Digital Repository Service at National Institute of Oceanography (India)

    SupritKumar; Shankar, D.

    Simulation studies are carried out to estimate the discharge of the Mandovi River, Goa. The Mandovi River catchment area includes the slopes of the Sahyadris, where estimates of precipitation are not available. A multivariate interpolation scheme...

  7. 2009 Oregon Parks and Recreation Department Lidar: Columbia River

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data set represents the lidar elevations along the Columbia River corridor in Oregon, including portions of the following counties: Gilliam, Hood River,...

  8. Environmental contaminants in aquatic resources from the Columbia River

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Columbia River is an important resource for fish and wildlife, and a number of National Wildlife Refuges (NWRs) were established along the river to protect...

  9. Special report of Horsefeldt-White River patrol

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers a patrol made by horseback and pack train from the headwaters of the copper River across the upper drainage to the Tanana River and terminating on...

  10. UMRS LTRMP 2010/11 LCU Mapping -- Open River South

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Aerial photographs for Pools 1-13 Upper Mississippi River System and Pools, Alton-Marseilles, Illinois River were collected in color infrared (CIR) in August of 2010...

  11. The Marketing of River Forwarding and Freight Services

    National Research Council Canada - National Science Library

    Georgeta Modiga

    2015-01-01

    River forwarding and freight contain, on the one hand, the movement of goods on the river and on the other hand, services related to handling, storage, issuance of documents and payment of all rendered services...

  12. Channel centerline for the Rogue River, Oregon in 2005

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Rogue River drains 13,390 square kilometers of southwestern Oregon before flowing into the Pacific Ocean near the town of Gold Beach, Oregon. The Rogue River...

  13. The Mystic River Watershed Initiative Steering Committee Purpose and Structure

    Science.gov (United States)

    The Mystic River Watershed Initiative (MRWI) works to improve water quality and public access to open spaces in the Mystic River watershed. The MRWI Steering Committee meets regularly to discuss key issues and priority actions related to this initiative.

  14. Pesticide residues in four rivers running through an intensive ...

    African Journals Online (AJOL)

    sediments from four rivers running through sugarcane plantations in Kilimanjaro Tanzania. The aim was to assess the levels of pesticide contamination as the rivers are important sources of domestic water in the area. Water samples were ...

  15. AFSC/ABL: Movements of Yukon River Chinook salmon

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Upriver movements were determined for Chinook salmon Oncorhynchus tshawytscha returning to the Yukon River, a large, relatively pristine river basin. A total of...

  16. Channel centerline for the Rogue River, Oregon in 2009

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The Rogue River drains 13,390 square kilometers of southwestern Oregon before flowing into the Pacific Ocean near the town of Gold Beach, Oregon. The Rogue River...

  17. Managing the wetlands. People and rivers: Africa.

    Science.gov (United States)

    Dugan, P

    1993-01-01

    At the current population growth rate in Africa, the population will reach 1 billion by 2010. Water is needed to sustain these people, yet rainfall in Africa is erratic. Africans are already confronting a shortage of freshwater. Agriculture supports 66% of the population of sub-Saharan Africa. Sound agricultural development is needed to curb rural-urban migration, but a constant supply of freshwater is essential. Major rivers (the Limpopo in southern Africa and the Save/Sabi in Zimbabwe and Mozambique) now flow only seasonally. The flows of the Chari-Logona, the Nile, and the Zambezi are falling. Continual mismanagement of Africa's river basins coupled with current projections of global climate change will expand desiccation. All but the White Nile and the Zaire rivers flood seasonally every year, thereby expanding Africa's wetlands. Wetlands have been targeted for development projects (e.g., hydroelectric projects and large dams), largely to meet urban-industrial demands. Development planners tend to ignore the economic value of the wetlands. For example, the Niger Inland Delta sustains 550,000 people, 1 million cattle, and 1 million sheep. Wetlands replenish ground water and serve as natural irrigation. River basin planning often results in environmentally disastrous schemes which do not understand local management practices. Hydrologists, engineers, geologists, and economics design these schemes, but sociologists, anthropologists, and development experts should be included. The unfinished Jonglei Canal in southern Sudan would have adversely affected 400,000 pastoralists. The Volta River Authority's Akosombo Dam displaced 84,000 people and flooded the most productive agricultural land in Ghana. A sustainable future in Africa depends on understanding the interactions of human uses and the ways in which they relate to the natural variations in river flow. The IUCN Wetlands Programme, based on the principles of the World Conservation Strategy, is working with

  18. Automatic River Network Extraction from LIDAR Data

    Science.gov (United States)

    Maderal, E. N.; Valcarcel, N.; Delgado, J.; Sevilla, C.; Ojeda, J. C.

    2016-06-01

    National Geographic Institute of Spain (IGN-ES) has launched a new production system for automatic river network extraction for the Geospatial Reference Information (GRI) within hydrography theme. The goal is to get an accurate and updated river network, automatically extracted as possible. For this, IGN-ES has full LiDAR coverage for the whole Spanish territory with a density of 0.5 points per square meter. To implement this work, it has been validated the technical feasibility, developed a methodology to automate each production phase: hydrological terrain models generation with 2 meter grid size and river network extraction combining hydrographic criteria (topographic network) and hydrological criteria (flow accumulation river network), and finally the production was launched. The key points of this work has been managing a big data environment, more than 160,000 Lidar data files, the infrastructure to store (up to 40 Tb between results and intermediate files), and process; using local virtualization and the Amazon Web Service (AWS), which allowed to obtain this automatic production within 6 months, it also has been important the software stability (TerraScan-TerraSolid, GlobalMapper-Blue Marble , FME-Safe, ArcGIS-Esri) and finally, the human resources managing. The results of this production has been an accurate automatic river network extraction for the whole country with a significant improvement for the altimetric component of the 3D linear vector. This article presents the technical feasibility, the production methodology, the automatic river network extraction production and its advantages over traditional vector extraction systems.

  19. River Flow Regimes and Effective Discharge

    Science.gov (United States)

    Basso, S.; Sprocati, R.; Frascati, A.; Marani, M.; Schirmer, M.; Botter, G.

    2015-12-01

    The concept of effective discharge is widespread in geomorphology and river engineering and restoration. For example, it is used to design the most stable channel configuration, to estimate sedimentation rate and lifespan of reservoirs and to characterize the hydrologic forcing in models studying long-term evolution of rivers. Accordingly, the effective discharge has been the focus of countless empirical, theoretical and numerical studies, which found it to vary among catchments as a function of climate, landscape and river morphology, type of transport (dissolved, suspended or bedload), and of streamflow variability. The heterogeneity of the effective discharge values observed in different catchments challenges a thorough understanding of its pivotal drivers, and a consistent framework which explains observations carried out in different geographic areas is still lacking. In the present work, the observed diversity is explained in terms of the underlying heterogeneity of river flow regimes, by linking effective discharge to attributes of the sediment rating curve and to streamflow variability, as resulting from climatic and landscape drivers. An analytic expression of the effective ratio (i.e. the ratio between effective discharge and mean streamflow) is provided, which captures observed values of effective discharge for suspended sediment transport in a set of catchments of the continental United States. The framework disentangles hydrologic and landscape controls on effective discharge, and highlights distinct effective ratios of persistent and erratic hydrologic regimes (respectively characterized by low and high flow variability), attributable to intrinsically different streamflow dynamics. Clusters of river catchments characterized by similar streamflow dynamics can be identified. The framework provides an opportunity for first-order estimates of effective discharge in rivers belonging to different areas, based on the type of flow regime.

  20. AUTOMATIC RIVER NETWORK EXTRACTION FROM LIDAR DATA

    Directory of Open Access Journals (Sweden)

    E. N. Maderal

    2016-06-01

    Full Text Available National Geographic Institute of Spain (IGN-ES has launched a new production system for automatic river network extraction for the Geospatial Reference Information (GRI within hydrography theme. The goal is to get an accurate and updated river network, automatically extracted as possible. For this, IGN-ES has full LiDAR coverage for the whole Spanish territory with a density of 0.5 points per square meter. To implement this work, it has been validated the technical feasibility, developed a methodology to automate each production phase: hydrological terrain models generation with 2 meter grid size and river network extraction combining hydrographic criteria (topographic network and hydrological criteria (flow accumulation river network, and finally the production was launched. The key points of this work has been managing a big data environment, more than 160,000 Lidar data files, the infrastructure to store (up to 40 Tb between results and intermediate files, and process; using local virtualization and the Amazon Web Service (AWS, which allowed to obtain this automatic production within 6 months, it also has been important the software stability (TerraScan-TerraSolid, GlobalMapper-Blue Marble , FME-Safe, ArcGIS-Esri and finally, the human resources managing. The results of this production has been an accurate automatic river network extraction for the whole country with a significant improvement for the altimetric component of the 3D linear vector. This article presents the technical feasibility, the production methodology, the automatic river network extraction production and its advantages over traditional vector extraction systems.