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Sample records for kachemak bay water

  1. National Status and Trends: Bioeffects Program - Kachemak Bay Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This study was based on the sediment quality triad (SQT) approach. A stratified probabilistic sampling design was utilized to characterize the Kachemak Bay system in...

  2. Juvenile groundfish habitat in Kachemak Bay, Alaska, during late summer

    Science.gov (United States)

    Abookire, Alisa A.; Piatt, J.F.; Norcross, Brenda L.

    2001-01-01

    We investigated the habitat of juvenile groundfishes in relation to depth, water temperature, and salinity in Kachemak Bay, Alaska. Stations ranging in depth from 10 to 70 m and with sand or mud-sand substrates were sampled with a small-meshed beam trawl in August-September of 1994 to 1999. A total of 8,201 fishes were captured, comprising at least 52 species. Most fishes (91%) had a total length 5% of the total catch) were flathead sole Hippoglossoides elassodon, slim sculpin Radulinus asprellus, Pacific halibut Hippoglossus stenolepis, and arrowtooth flounder Atheresthes stomias. Depth accounted for most of the spatial variability in juvenile groundfish abundance, and neither temperature nor salinity was correlated with fish abundance. Juvenile groundfishes concentrated in either shallow (less than or equal to 20 m) or deep (50-70 m) water, with co-occurrence of some species between 30-40 m. Shallow fishes were the rock soles, Pacific halibut, and great sculpin Myoxocephalus polyacanthocephalus. Deep species were flathead sole, slim sculpin, spinycheek starsnout Bathyagonus infraspinatus, rex sole Glyptocephalus zachirus, tadpole sculpin Psychrolutes paradoxus, and whitebarred prickleback Poroclinus rothrocki. This 6-year study provides baseline data on relative abundance and distribution of juvenile groundfishes in Kachemak Bay and may provide a useful tool for predicting the presence of species in similar habitats in other areas of Alaska.

  3. Winter feeding ecology and trophic relationships of marine birds in Kachemak Bay, Alaska: Final report to the Outer Continental Shelf Environmental Assessment Program

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The winter feeding ecology of oldsquaw, white-winged scoters, common murres and marbled murrelet was studied on Kachemak Bay, Alaska, from November 1977 through...

  4. Sound velocity, temperature, and salinity profiles from underway vessel profiler and CTD casts from NOAA Ship FAIRWEATHER in Kachemak Bay, Gulf of Alaska, from 2008-06-16 to 2008-09-02 (NCEI Accession 0048723)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Physical oceanographic data were collected from NOAA Ship FAIRWEATHER in Kachemak Bay, Gulf of Alaska, from 16 June 2008 to 02 September 2008. Data were collected...

  5. Field guide to the Mesozoic accretionary complex along Turnagain Arm and Kachemak Bay, south-central Alaska

    Science.gov (United States)

    Bradley, Dwight C.; Kusky, Timothy M.; Karl, Susan M.; Haeussler, Peter J.

    1997-01-01

    Turnagain Arm, just east of Anchorage, provides a readily accessible, world-class cross section through a Mesozoic accretionary wedge. Nearly continuous exposures along the Seward Highway, the Alaska Railroad, and the shoreline of Turnagain Arm display the two main constituent units of the Chugach terrane: the McHugh Complex and Valdez Group. In this paper we describe seven bedrock geology stops along Turnagain Arm, and two others in the Chugach Mountains just to the north (Stops 1-7 and 9), which will be visited as part of the May, 1997 field trip of the Alaska Geological Society. Outcrops along Turnagain Arm have already been described in two excellent guidebook articles (Clark, 1981; Winkler and others 1984), both of which remain as useful and valid today as when first published. Since the early 1980's, studies along Turnagain Arm have addressed radiolarian ages of chert and conodont ages of limestone in the McHugh Complex (Nelson and others, 1986, 1987); geochemistry of basalt in the McHugh Complex (Nelson and Blome, 1991); post-accretion brittle faulting (Bradley and Kusky, 1990; Kusky and others, 1997); and the age and tectonic setting of gold mineralization (Haeussler and others, 1995). Highlights of these newer findings will described both in the text below, and in the stop descriptions.Superb exposures along the southeastern shore of Kachemak Bay show several other features of the McHugh Complex that are either absent or less convincing along Turnagain Arm. While none of these outcrops can be reached via the main road network, they are still reasonably accessible - all are within an hour by motorboat from Homer, seas permitting. Here, we describe seven outcrops along the shore of Kachemak Bay that we studied between 1989 and 1993 during geologic mapping of the Seldovia 1:250,000- scale quadrangle. These outcrops (Stops 61-67) will not be part of the 1997 itinerary, but are included here tor the benefit of those who may wish to visit them later.

  6. kachemak_bay_ak.grd

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NGDC builds and distributes high-resolution, coastal digital elevation models (DEMs) that integrate ocean bathymetry and land topography to support NOAA's mission to...

  7. Kachemak Bay, Alaska Coastal Digital Elevation Model

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA's National Geophysical Data Center (NGDC) is building high-resolution digital elevation models (DEMs) for select U.S. coastal regions. These integrated...

  8. SF Bay Water Quality Improvement Fund

    Science.gov (United States)

    EPAs grant program to protect and restore San Francisco Bay. The San Francisco Bay Water Quality Improvement Fund (SFBWQIF) has invested in 58 projects along with 70 partners contributing to restore wetlands, water quality, and reduce polluted runoff.,

  9. Deriving Chesapeake Bay Water Quality Standards

    Science.gov (United States)

    Tango, Peter J.; Batiuk, Richard A.

    2013-01-01

    Achieving and maintaining the water quality conditions necessary to protect the aquatic living resources of the Chesapeake Bay and its tidal tributaries has required a foundation of quantifiable water quality criteria. Quantitative criteria serve as a critical basis for assessing the attainment of designated uses and measuring progress toward meeting water quality goals of the Chesapeake Bay Program partnership. In 1987, the Chesapeake Bay Program partnership committed to defining the water quality conditions necessary to protect aquatic living resources. Under section 303(c) of the Clean Water Act, States and authorized tribes have the primary responsibility for adopting water quality standards into law or regulation. The Chesapeake Bay Program partnership worked with U.S. Environmental Protection Agency to develop and publish a guidance framework of ambient water quality criteria with designated uses and assessment procedures for dissolved oxygen, water clarity, and chlorophyll a for Chesapeake Bay and its tidal tributaries in 2003. This article reviews the derivation of the water quality criteria, criteria assessment protocols, designated use boundaries, and their refinements published in six addendum documents since 2003 and successfully adopted into each jurisdiction's water quality standards used in developing the Chesapeake Bay Total Maximum Daily Load.

  10. SF Bay Water Quality Improvement Fund: Projects and Accomplishments

    Science.gov (United States)

    San Francisco Bay Water Quality Improvement Fund (SFBWQIF) projects listed here are part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

  11. Spatial and temporal characterizations of water quality in Kuwait Bay.

    Science.gov (United States)

    Al-Mutairi, N; Abahussain, A; El-Battay, A

    2014-06-15

    The spatial and temporal patterns of water quality in Kuwait Bay have been investigated using data from six stations between 2009 and 2011. The results showed that most of water quality parameters such as phosphorus (PO4), nitrate (NO3), dissolved oxygen (DO), and Total Suspended Solids (TSS) fluctuated over time and space. Based on Water Quality Index (WQI) data, six stations were significantly clustered into two main classes using cluster analysis, one group located in western side of the Bay, and other in eastern side. Three principal components are responsible for water quality variations in the Bay. The first component included DO and pH. The second included PO4, TSS and NO3, and the last component contained seawater temperature and turbidity. The spatial and temporal patterns of water quality in Kuwait Bay are mainly controlled by seasonal variations and discharges from point sources of pollution along Kuwait Bay's coast as well as from Shatt Al-Arab River.

  12. Characteristics of nearshore waters in Binge Bay, Karwar

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Singbal, S.Y.S.

    Environmental parameters to delineate characteristics of nearshore waters were studied over one year in Binge Bay. Existence of low temperature, high saline, low dissolved oxygen and high nutrient water during August-October at the bottom...

  13. Chesapeake Bay Program Water Quality Database

    Data.gov (United States)

    U.S. Environmental Protection Agency — The Chesapeake Information Management System (CIMS), designed in 1996, is an integrated, accessible information management system for the Chesapeake Bay Region....

  14. Shallow-water Benthic Habitats in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of Jobos Bay, Puerto Rico were mapped and characterized using visual interpretation...

  15. Marsh and Water Management Plan: Back Bay National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Back Bay National Wildlife Refuge Marsh and Water Management Plan has been developed to meet the station objectives set forth in the Master Plan. The purpose of...

  16. Index for Assessing Water Trophic Status in Semi-Enclosed Cuban Bays. Case Study: Cienfuegos Bay

    CERN Document Server

    Seisdedo, Mabel; Arencibia, Gustavo

    2013-01-01

    This paper aims at contributing to the coastal environmental management by developing a new trophic status index of the water (TSIW). The index is tailored to semi-enclosed bays with estuarine characteristic like the Cienfuegos bay in Cuba. We also propose pressure indicators related to exporting and assimilation capacities as a tool to assess the vulnerability of the system to eutrophication. The TSIW is based on response indicators to eutrophication processes showing correspondence with the predefined pressure indicators and previous reports on water quality. Thus, the proposed trophic status index is a reliable scientific tool to measure the current stage of the water quality and to establish a baseline for further studies.

  17. Dissolved platinum in rainwater, river water and seawater around Tokyo Bay and Otsuchi Bay in Japan

    Science.gov (United States)

    Mashio, Asami Suzuki; Obata, Hajime; Tazoe, Hirofumi; Tsutsumi, Makoto; Ferrer i Santos, Antoni; Gamo, Toshitaka

    2016-10-01

    Platinum, among the rarest elements in the earth's crust, is now widely used in various products such as catalytic converters in automobiles and anticancer drugs. Consequently, the concentration of Pt in urban aquatic environments might be increasing. However, little is known about the distributions and geochemical cycles of Pt in aquatic environments because its overall concentration remains low. In this study, we examined dissolved Pt in river water and seawater around Tokyo Bay and Otsuchi Bay (Iwate Prefecture, Japan) and rainwater in the Tokyo area. To determine sub-picomolar levels of dissolved Pt, we used isotope-dilution Inductively Coupled Plasma Mass Spectrometry (ICP-MS) after column preconcentration with an anion exchange resin. We observed seasonal variation in the dissolved Pt concentrations in Tokyo rainwater in 2002; higher concentrations were found from January to March, which might be related to the pH of rainwaters. At the source of the Arakawa River in the greater Tokyo area, the dissolved Pt concentration was found to be similar to that in rainwater. Further downstream, the dissolved Pt concentration increased sharply, which seemingly reflects the anthropogenic input of Pt into the river. In a rural area in Japan (Otsuchi Bay), the dissolved Pt concentrations were lower than in Tokyo Bay. In this area, a sharp increase in dissolved Pt concentrations was observed in a high salinity region. Contrasting Pt distribution patterns between urban and rural areas indicate that strong anthropogenic Pt sources exist in urban estuaries and that geochemical processes within estuaries affect the Pt distribution.

  18. Risk assessment for produced water discharges to Louisiana Open Bays

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.

    1995-06-23

    Data were collected prior to termination of discharge at three sites (including two open bay sites at Delacroix Island and Bay De Chene) for the risk assessments. The Delacroix Island Oil and Gas Field has been in production since the first well drilling in 1940; the Bay De Chene Field, since 1942. Concentrations of 226Ra, 228Ra, 210Po, and 228Th were measured in discharges. Radium conc. were measured in fish and shellfish tissues. Sediment PAH and metal conc. were also available. Benthos sampling was conducted. A survey of fishermen was conducted. The tiered risk assessment showed that human health risks from radium in produced water appear to be small; ecological risk from radium and other radionuclides in produced water also appear small. Many of the chemical contaminants discharged to open Louisiana bays appear to present little human health or ecological risk. A conservative screening analysis suggested potential risks to human health from Hg and Pb and a potential risk to ecological receptors from total effluent, Sb, Cd, Cu, Pb, Ni, Ag, Zn, and phenol in the water column and PAHs in sediment; quantitiative risk assessments are being done for these contaminants.

  19. Waste water discharge and its effect on the quality of water of Mahim creek and bay

    Digital Repository Service at National Institute of Oceanography (India)

    Zingde, M.D.; Desai, B.N.

    Coastal environment around Mahim was monitored to evaluate the effects of domestic and industrial waste water discharge in Mahim Creek, Maharashtra, India. Vertical salinity and DO gradient occasionally observed in the Mahim Bay during postmonsoon...

  20. Water characteristics, mixing and circulation in the Bay of Bengal during southwest monsoon

    Digital Repository Service at National Institute of Oceanography (India)

    Murty, V.S.N.; Sarma, Y.V.B.; Rao, D.P.; Murty, C.S.

    Influence of the freshwater influx, the wind forcing and the Indian Ocean monsoon drift current on the property distributions and the circulation in the Bay of Bengal during southwest monsoon has been quantified. At the head of the Bay, waters...

  1. Anthropogenic currents and shoreline water quality in Avalon Bay, California.

    Science.gov (United States)

    Ho, Lin C; Litton, Rachel M; Grant, Stanley B

    2011-03-15

    Shoreline concentrations of fecal indicator bacteria (FIB) and fecal indicator viruses (FIV) in Avalon Bay (Catalina Island, California) display a marked diurnal pattern (higher at night and lower during the day) previously attributed to the tidal flux of sewage-contaminated groundwater and the tidal washing of contaminated sediments, coupled with light and dark die-off of FIB and FIV (Boehm, et al., Environ. Sci. Technol. 2009, 43, 8046-8052). In this paper we document the existence of strong (peak velocities between 20 to 40 cm/s) transient currents in the nearshore waters of Avalon Bay that occur between 07:00 and 20:00 each day. These currents, which have a significant onshore component, are generated by anthropogenic activities in the Bay, including prop wash from local boat traffic and the docking practices of large passenger ferries. A budget analysis carried out on simultaneous measurements of FIB at two cross-shore locations indicates that anthropogenic currents contribute to the diurnal cycling of FIB concentrations along the shoreline, by transporting relatively unpolluted water from offshore toward the beach. The data and analysis presented in this paper support the idea that anthropogenic currents represent a significant, and previously overlooked, source of variability in shoreline water quality.

  2. Supercooled water in austral summer in Prydz Bay,Antarctica

    Institute of Scientific and Technical Information of China (English)

    SHI Jiuxin; CHENG Yaoyao; JIAO Yutian; HOU Jiaqiang

    2011-01-01

    Supercooled water with temperatures below freezing point, was identified from hydrographic data obtained by Chinese and Australian expeditions to Prydz Bay, Antarctica, during the austral summer. The study shows that most supercooled waters occurred at depths of 63-271 m in the region north of the Amery Ice Shelf (AIS) front. The maximum supercooling was 0.16℃ below the in-situ freezing point. In temperature and salinity ranges of-2.14 - -1.96℃ and 34.39--34.46, respectively,the water was colder and fresher than peripheral shelf water. The supercooled water had less variability in the vertical profiles compared to shelf water. Based on analysis of their thermohaline features and spatial distribution, as well as the circulation pattern in Prydz Bay, we conclude that these supercooled waters originated from a cavity beneath the AIS and resulted from upwelling just outside of the AIS front. Water emerging from the ice shelf cools to an extremely low temperature (about -2.0℃) by additional cooling from the ice shelf, and becomes buoyant with the addition of melt water from the ice shelf base. When this water flows out of the ice shelf front, its upper boundary is removed, and thus it rises abruptly. Once the temperature of this water reaches below the freezing point, supercooling takes place. In summer, the seasonal pycnocline at ~100 m water depth acts as a barrier to upwelling and supercooling. The upwelling of ice shelf outflow water illuminates a unique mid-depth convection of the polar ocean.

  3. Record-high specific conductance and water temperature in San Francisco Bay during water year 2015

    Science.gov (United States)

    Work, Paul; Downing-Kunz, Maureen; Livsey, Daniel

    2017-02-22

    The San Francisco estuary is commonly defined to include San Francisco Bay (bay) and the adjacent Sacramento–San Joaquin River Delta (delta). The U.S. Geological Survey (USGS) has operated a high-frequency (15-minute sampling interval) water-quality monitoring network in San Francisco Bay since the late 1980s (Buchanan and others, 2014). This network includes 19 stations at which sustained measurements have been made in the bay; currently, 8 stations are in operation (fig. 1). All eight stations are equipped with specific conductance (which can be related to salinity) and water-temperature sensors. Water quality in the bay constantly changes as ocean tides force seawater in and out of the bay, and river inflows—the most significant coming from the delta—vary on time scales ranging from those associated with storms to multiyear droughts. This monitoring network was designed to observe and characterize some of these changes in the bay across space and over time. The data demonstrate a high degree of variability in both specific conductance and temperature at time scales from tidal to annual and also reveal longer-term changes that are likely to influence overall environmental health in the bay.In water year (WY) 2015 (October 1, 2014, through September 30, 2015), as in the preceding water year (Downing-Kunz and others, 2015), the high-frequency measurements revealed record-high values of specific conductance and water temperature at several stations during a period of reduced freshwater inflow from the delta and other tributaries because of persistent, severe drought conditions in California. This report briefly summarizes observations for WY 2015 and compares them to previous years that had different levels of freshwater inflow.

  4. WATER POLLUTION IN THE RIVER MOUTHS AROUND BOHAI BAY

    Institute of Scientific and Technical Information of China (English)

    Cheng LIU; Zhao-Yin WANG; Yun HE

    2003-01-01

    Twelve water samples were collected and analyzed. The samples were taken from the river mouths around Bohai Bay including the Jiyun, New Yongding, Haihe, Dagu, Duliujian, Qingjinghuang, Qikou, Dakou, and Yellow Rivers, and tested for concentrations of heavy metals, arsenic, total nitrogen (TN) and total phosphorus (TP). The results show that the river mouths are polluted and the water quality exceeds Class V of the Environmental Quality Standard for Surface Water (EQSSW). The main pollutants are Hg, nitrogen (N) and phosphorus (P). The concentrations of the other pollutants are within Class Ⅱ of the Standard. The Hg content in the Haihe River mouth is now 10 times higher than it was 20 years ago, indicating that the accelerating water pollution has reached an alarming level. The high concentrations of N and P cause eutrophication of the waters.Analysis indicates that the terrestrial pollutants and nutrients are the main cause of frequently occurring red tides in the Bohai Sea.

  5. Observations and a linear model of water level in an interconnected inlet-bay system

    Science.gov (United States)

    Aretxabaleta, Alfredo L.; Ganju, Neil K.; Butman, Bradford; Signell, Richard P.

    2017-04-01

    A system of barrier islands and back-barrier bays occurs along southern Long Island, New York, and in many coastal areas worldwide. Characterizing the bay physical response to water level fluctuations is needed to understand flooding during extreme events and evaluate their relation to geomorphological changes. Offshore sea level is one of the main drivers of water level fluctuations in semienclosed back-barrier bays. We analyzed observed water levels (October 2007 to November 2015) and developed analytical models to better understand bay water level along southern Long Island. An increase (˜0.02 m change in 0.17 m amplitude) in the dominant M2 tidal amplitude (containing the largest fraction of the variability) was observed in Great South Bay during mid-2014. The observed changes in both tidal amplitude and bay water level transfer from offshore were related to the dredging of nearby inlets and possibly the changing size of a breach across Fire Island caused by Hurricane Sandy (after December 2012). The bay response was independent of the magnitude of the fluctuations (e.g., storms) at a specific frequency. An analytical model that incorporates bay and inlet dimensions reproduced the observed transfer function in Great South Bay and surrounding areas. The model predicts the transfer function in Moriches and Shinnecock bays where long-term observations were not available. The model is a simplified tool to investigate changes in bay water level and enables the evaluation of future conditions and alternative geomorphological settings.

  6. Observations and a linear model of water level in an interconnected inlet-bay system

    Science.gov (United States)

    Aretxabaleta, Alfredo; Ganju, Neil Kamal; Butman, Bradford; Signell, Richard

    2017-01-01

    A system of barrier islands and back-barrier bays occurs along southern Long Island, New York, and in many coastal areas worldwide. Characterizing the bay physical response to water level fluctuations is needed to understand flooding during extreme events and evaluate their relation to geomorphological changes. Offshore sea level is one of the main drivers of water level fluctuations in semienclosed back-barrier bays. We analyzed observed water levels (October 2007 to November 2015) and developed analytical models to better understand bay water level along southern Long Island. An increase (∼0.02 m change in 0.17 m amplitude) in the dominant M2 tidal amplitude (containing the largest fraction of the variability) was observed in Great South Bay during mid-2014. The observed changes in both tidal amplitude and bay water level transfer from offshore were related to the dredging of nearby inlets and possibly the changing size of a breach across Fire Island caused by Hurricane Sandy (after December 2012). The bay response was independent of the magnitude of the fluctuations (e.g., storms) at a specific frequency. An analytical model that incorporates bay and inlet dimensions reproduced the observed transfer function in Great South Bay and surrounding areas. The model predicts the transfer function in Moriches and Shinnecock bays where long-term observations were not available. The model is a simplified tool to investigate changes in bay water level and enables the evaluation of future conditions and alternative geomorphological settings.

  7. Risk assessment for produced water discharges to Louisiana open bays

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, A.F.; Holtzman, S.; DePhillips, M.P.

    1995-11-01

    Potential human health and environmental impacts from discharge of produced water to the Gulf of Mexico concern regulators at the State and Federal levels, environmental interest groups, industry and the public. Current regulations in the United States require or propose azero discharge limit for coastal facilities based primarily on studies performed in low energy,poorly flushed environments. Produced water discharges in coastal Louisiana, however,include a number located in open bays, where potential and impacts are likely to be larger than the minimal impacts associated with offshore discharges, but smaller than those demonstrated in low-energy canal environments. This paper summarizes results of a conservative screening-level health and ecological assessment for contaminants discharged in produced water to open bays in Louisiana, and reports results of a probabilistic human health risk assessment for radium and lead. The initial human health and ecological risk assessments consisted of conservative screening analyses that identified potentially important contaminants and excluded others from further consideration. A more quantitative probabilistic risk assessment was completed for the human health effects of the two contaminants identified in this screen: radium and lead. This work is part of a series of studies on the health and ecological risks from discharges of produced water to the Gulf of Mexico, supported by the United States Department of Energy (USDOE).

  8. 2008 NOAA Aerial Photography (IR) of Alaska: Kachemak Bay: Integrated Ocean and Coastal Mapping Product

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Integrated Ocean and Coastal Mapping (IOCM) Product. The images were acquired from a nominal altitude of 5,000 feet above ground level (AGL), using an Applanix...

  9. The winter feeding ecology and trophic relationships of marine birds in Kachemak Bay, Alaska [Draft

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The primary objectives of the study were; (1) to determine the kinds, amounts, and trophic levels of prey used by the main species of marine birds wintering on the...

  10. Breeding seabirds at Gull Island and Sixty-foot Rock, Kachemak Bay, during 1984-86

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Full monitoring of Black- legged kittiwakes, glaucous winged gulls, common murres, and tufted puffins discovered large population increases since a prior survey in...

  11. The winter feeding habits of selected species of marine birds in Kachemak Bay, Alaska: Annual report

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report summarizes the findings of a study on winter feeding habits and ecology of marine birds in lower Cook Inlet. Monthly field operations commenced in...

  12. H11935: NOS Hydrographic Survey , Kachemak Bay, Alaska, 2008-09-02

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The National Oceanic and Atmospheric Administration (NOAA) has the statutory mandate to collect hydrographic data in support of nautical chart compilation for safe...

  13. Assessment for water quality by artificial neural network in Daya Bay, South China Sea.

    Science.gov (United States)

    Wu, Mei-Lin; Wang, You-Shao; Gu, Ji-Dong

    2015-10-01

    In this study, artificial neural network such as a self-organizing map (SOM) was used to assess for the effects caused by climate change and human activities on the water quality in Daya Bay, South China Sea. SOM has identified the anthropogenic effects and seasonal characters of water quality. SOM grouped the four seasons as four groups (winter, spring, summer and autumn). The Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on the water quality in Daya Bay. Spatial pattern is mainly related to anthropogenic activities and hydrodynamics conditions. In spatial characteristics, the water quality in Daya Bay was divided into two groups by chemometrics. The monitoring stations (S3, S8, S10 and S11) were in these area (Dapeng Ao, Aotou Harbor) and northeast parts of Daya Bay, which are areas of human activity. The thermal pollution has been observed near water body in Daya Bay Nuclear Power Plant (S5). The rest of the monitoring sites were in the south, central and eastern parts of Daya Bay, which are areas that experience water exchanges from South China Sea. The results of this study may provide information on the spatial and temporal patterns in Daya Bay. Further research will be carry out more research concerning functional changes in the bay ecology with respect to changes in climatic factor, human activities and bay morphology in Daya Bay.

  14. Upper layer waters and their northward extension from Prydz Bay in summer

    Institute of Scientific and Technical Information of China (English)

    蒲书箴; 董兆乾; 胡筱敏; 于非; 陈幸荣

    2001-01-01

    In this paper, CTD observational data obtained during the 15th Chinese National Antarctic Research Expedition (CHINARE-15) in the Southern Ocean are used to analyse and study water mass distribution in the Prydz Bay and its adjacent seas. The area, depth, and the thermohaline characteristics are identified for the Prydz Bay summer coastal surface water, the Prydz Bay winter water, the Prydz Bay shelf water, and the circumpolar deep water. Based on the above discussion, the northward extention of the Prydz Bay shelf water are found. Then the thermodynamic and the dynamic characteristics are further discussed, dealing with the inversion layer depth of the water temperature, the locations of the minima of the vertical temperature distribution and the temperature vertical gradient in the water column, the baraclinicity, and the effect of Coriolis deflection force.

  15. Water level oscillations in Monterey Bay and Harbor

    Directory of Open Access Journals (Sweden)

    J. Park

    2015-06-01

    Full Text Available Seiches are normal modes of water bodies responding to geophysical forcings with potential to significantly impact ecology and maritime operations. Analysis of high-frequency (1 Hz water level data in Monterey, California, identifies harbor modes between 10 and 120 s that are attributed to specific geographic features. It is found that modal amplitude modulation arises from cross-modal interaction and that offshore wave energy is a primary driver of these modes. Synchronous coupling between modes is observed to significantly impact dynamic water levels. At lower frequencies with periods between 15 and 60 min, modes are independent of offshore wave energy, yet are continuously present. This is unexpected since seiches normally dissipate after cessation of the driving force, indicating an unknown forcing. Spectral and kinematic estimates of these low-frequency oscillations support the idea that a persistent anticyclonic mesoscale gyre adjacent to the bay is a potential mode driver, while discounting other sources.

  16. Water level oscillations in Monterey Bay and Harbor

    Directory of Open Access Journals (Sweden)

    J. Park

    2014-11-01

    Full Text Available Seiches are normal modes of water bodies responding to geophysical forcings with potential to significantly impact ecology and maritime operations. Analysis of high-frequency (1 Hz water level data in Monterey California identifies Harbor modes between 10 and 120 s that are attributed with specific geographic features. It found that modal amplitude modulation arises from cross-modal interaction and that offshore wave energy is a primary driver of these modes. Synchronous coupling between modes is observed to significantly impact dynamic water levels. At lower frequencies between 15 and 60 min modes are independent of offshore wave energy, yet are continuously present. This is unexpected since seiches normally dissipate after cessation of the driving force, indicating an unknown forcing. Spectral and kinematic estimates of these low frequency oscillations supports the idea that a persistent anticyclonic mesoscale gyre adjacent to the Bay is a potential mode driver, while discounting other sources.

  17. 77 FR 75017 - Security Zone; On the Waters in Kailua Bay, Oahu, HI

    Science.gov (United States)

    2012-12-19

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; On the Waters in Kailua Bay, Oahu, HI... to read as follows: Sec. 165.T14-215 Security Zone; On the Waters in Kailua Bay, Oahu, HI....

  18. 76 FR 12 - Security Zone; On the Waters in Kailua Bay, Oahu, HI

    Science.gov (United States)

    2011-01-03

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; On the Waters in Kailua Bay, Oahu, HI... to read as follows: Sec. 165.T14-215 Security Zone; On the Waters in Kailua Bay, Oahu, HI....

  19. 78 FR 79312 - Security Zone; On the Waters in Kailua Bay, Oahu, HI

    Science.gov (United States)

    2013-12-30

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; On the Waters in Kailua Bay, Oahu, HI... Security Zone; On the Waters in Kailua Bay, Oahu, HI. (a) Location. The following area, within the...

  20. Sediment-water fluxes of mercury in Lavaca Bay, Texas

    Energy Technology Data Exchange (ETDEWEB)

    Gill, G.A. [Texas A and M Univ., Galveston, TX (United States); Bloom, N.S. [Frontier Geosciences Inc., Seattle, WA (United States); Cappellino, S. [Parametrix, Inc., Houston, TX (United States); Driscoll, C.T. [Syracuse Univ., NY (United States). Dept. of Civil and Environmental Engineering; Dobbs, C.; McShea, L. [Aluminum Co. of America, Point Comfort, TX (United States); Mason, R. [Univ. of Maryland, Solomons, MD (United States). Chesapeake Biological Lab.; Rudd, J.W.M. [Dept. of Fisheries and Oceans, Winnipeg, Manitoba (Canada). Freshwater Inst.

    1999-03-01

    The aqueous flux of inorganic Hg and monomethyl Hg from sediments to the water column was determined at several sites in Lavaca Bay, an estuary along the Texas Coast, historically impacted by Hg discharges. Diffusive fluxes were calculated at 15 sites using interstitial pore water gradients and compared to direct flux measurements obtained at two sites using benthic flux chambers. The diffusive flux of monomethyl mercury (MMHg), when modeled as a chloride species, varied over 3 orders /of magnitude from 0.2 to 1500 ng m{sup {minus}2} day{sup {minus}1}. Diffusive fluxes determined at a single site revealed that MMHg fluxes varied seasonally; maximal fluxes occurred in late winter to early spring. Flux chamber deployments at an impacted site revealed t hat MMHg was the Hg species entering the water column from sediments and the flux was not in steady-state; there was a strong diurnal signal with most of the MMHg flux occurring during dark periods. The flux of inorganic Hg was smaller and not as easily discernible by this method. The MMHg flux during the dark period was about 6 times greater than the estimated diffusional flux for MMHgCl, suggesting that biological and/or chemical processes near the sediment-water interface were strongly mediating the sediment-water exchange of MMHg.

  1. Changes in Stream Water Temperatures in the Chesapeake Bay Region, 1960-2014

    Data.gov (United States)

    U.S. Environmental Protection Agency — This map shows the changes in stream water temperatures in the Chesapeake Bay region from 1960 to 2014. Blue circles represent cooling trends in stream water...

  2. Degradation of tributyltin in San Diego Bay, California, waters

    Energy Technology Data Exchange (ETDEWEB)

    Seligman, P.F.; Valkirs, A.O.; Lee, R.F.

    1986-12-01

    Several experiments were carried out to determine the degradation rate of tributyltin (TBT) in microcosms containing harbor water. Unlabeled or /sup 14/C-labeled tributyltin was added to water samples collected from two stations in San Diego Bay, CA. Degradation rates were determined by calculating the rate of loss of the added parent TBT compound. Calculated half-lives in water collected from a yacht harbor (ambient concentration was 0.5 ..mu..g of TBT/L) were 6 and 7 days for light and dark treatments, respectively. Half-lives from a clean-water site (< 0.03 ..mu..g of TBT/L) were 9 and 19 days for light and dark treatments, respectively. The principal degradation product in all experiments was dibutyltin with lesser amounts of monobutyltin. Complete mineralization, measured by the formation of /sup 14/CO/sub 2/, proceeded slowly with a half-life of 50-75 days. Tributyltin at high concentrations (744 ..mu..g/L) was not degraded in sunlight, indicating that photolysis was not taking place and that biological degradation was the primary degradative process for TBT at low ambient concentrations.

  3. Water level response in back-barrier bays unchanged following Hurricane Sandy

    Science.gov (United States)

    Aretxabaleta, Alfredo L.; Butman, Bradford; Ganju, Neil K.

    2014-01-01

    On 28–30 October 2012, Hurricane Sandy caused severe flooding along portions of the northeast coast of the United States and cut new inlets across barrier islands in New Jersey and New York. About 30% of the 20 highest daily maximum water levels observed between 2007 and 2013 in Barnegat and Great South Bay occurred in 5 months following Hurricane Sandy. Hurricane Sandy provided a rare opportunity to determine whether extreme events alter systems protected by barrier islands, leaving the mainland more vulnerable to flooding. Comparisons between water levels before and after Hurricane Sandy at bay stations and an offshore station show no significant differences in the transfer of sea level fluctuations from offshore to either bay following Sandy. The post-Hurricane Sandy bay high water levels reflected offshore sea levels caused by winter storms, not by barrier island breaching or geomorphic changes within the bays.

  4. Future trends in urbanization and coastal water pollution in the Bay of Bengal: the lived experience

    NARCIS (Netherlands)

    Zinia, N.J.; Kroeze, C.

    2015-01-01

    The Bay of Bengal includes coastal seas of several countries, including Bangladesh, India, and Myanmar. We present scenarios for future river export of eutrophying nutrients into the Bay of Bengal, and the role of urbanization therein. We used NEWS (Nutrient Export from WaterSheds) model to analyze

  5. 33 CFR 162.205 - Suisun Bay, San Joaquin River, Sacramento River, and connecting waters, CA.

    Science.gov (United States)

    2010-07-01

    .... (a) San Joaquin River Deep Water Channel between Suisun Bay and the easterly end of the channel at... Suisun Bay and easterly end of Turning Basin at West Sacramento; use, administration, and navigation—(1... North End Light at latitude 38°06′16″ N., longitude 121°42′32.5″ W.; thence easterly to latitude...

  6. 77 FR 50085 - Rookery Bay, FL and Kachemak Bay, AK National Estuarine Research Reserve Management Plan Revisions

    Science.gov (United States)

    2012-08-20

    ..., education, training and stewardship functions to address high priority issues including land use changes affecting freshwater inflow, loss of native biodiversity, lack of public awareness and community involvement... that connects the Environmental Learning Center to a boardwalk and interpretive trails describing...

  7. The suppression of Antarctic bottom water formation by melting ice shelves in Prydz Bay

    Science.gov (United States)

    Williams, G. D.; Herraiz-Borreguero, L.; Roquet, F.; Tamura, T.; Ohshima, K. I.; Fukamachi, Y.; Fraser, A. D.; Gao, L.; Chen, H.; McMahon, C. R.; Harcourt, R.; Hindell, M.

    2016-08-01

    A fourth production region for the globally important Antarctic bottom water has been attributed to dense shelf water formation in the Cape Darnley Polynya, adjoining Prydz Bay in East Antarctica. Here we show new observations from CTD-instrumented elephant seals in 2011-2013 that provide the first complete assessment of dense shelf water formation in Prydz Bay. After a complex evolution involving opposing contributions from three polynyas (positive) and two ice shelves (negative), dense shelf water (salinity 34.65-34.7) is exported through Prydz Channel. This provides a distinct, relatively fresh contribution to Cape Darnley bottom water. Elsewhere, dense water formation is hindered by the freshwater input from the Amery and West Ice Shelves into the Prydz Bay Gyre. This study highlights the susceptibility of Antarctic bottom water to increased freshwater input from the enhanced melting of ice shelves, and ultimately the potential collapse of Antarctic bottom water formation in a warming climate.

  8. Annual Marsh and Water Management Program: Back Bay National Wildlife Refuge

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Marsh and water management activities have been conducted for nearly thirty years at Back Bay NWR. Annual programs were submitted for many years. In the early 1970's...

  9. Shallow-water Benthic Habitat Map (2013) for Coral Bay, St. John

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This shapefile contains information about the shallow-water (<40 meters) geology and biology of the seafloor in Coral Bay, St. John in the U.S. Virgin Islands...

  10. Fresh Water Inflow and Oyster Productivity in Apalachicola Bay, FL (USA)

    Science.gov (United States)

    Apalachicola Bay lies at the mouth of the Apalachicola River, where seasonally variable freshwater inflows and shifting winds support an unusually productive and commercially important oyster fishery. While there is concern that upstream water withdrawals may impact the fishery,...

  11. A water bird survey in Bristol Bay and proposals for future studies

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper reports a preliminary attempt to census fall water bird populations in Bristol Bay within the zone from high tide to the 12-mile off shore limit. Aerial...

  12. A Water Movement Study in Lianzhou Bay, Guangxi Province,China

    Institute of Scientific and Technical Information of China (English)

    SUN Ting; Andreas Macrander; David Kaiser

    2014-01-01

    This study investigates the physical conditions (water depth, current speed, salinity, temperature) in Lianzhou Bay, a shallow coastal bay in southern China, during two expeditions in the dry and wet seasons of 2011. Based on these expedition data, basic hydrodynamic parameters like Brunt-Väisälä Frequency, Richardson Number, Rossby radius, and Resonance Period are calcu-lated. The results show that Lianzhou Bay is characterized by comparatively small quantity of freshwater input and weak stratifica-tion. Strong tides, which are spatially uniform within the bay, cause turbulent mixing. Residence time of the water is shorter in winter due to a stronger coastal current in that season. Consideration of the water movement may help to reduce the harmful ecological impact of aquaculture waste water discharge.

  13. Physical and chemical properties of San Francisco Bay waters, 1969-1976 (NODC Accession 8400194)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — One magnetic tape containing the physical and chemical properties of San Francisco Bay waters was forwarded to NODC by Mr. Richard Smith of the U.S Geological Survey...

  14. Subsurface structure of the East Bay Plain ground-water basin: San Francisco Bay to the Hayward fault, Alameda County, California

    Science.gov (United States)

    Catchings, R.D.; Borchers, J.W.; Goldman, M.R.; Gandhok, G.; Ponce, D.A.; Steedman, C.E.

    2006-01-01

    The area of California between the San Francisco Bay, San Pablo Bay, Santa Clara Valley, and the Diablo Ranges (East Bay Hills), commonly referred to as the 'East Bay', contains the East Bay Plain and Niles Cone ground-water basins. The area has a population of 1.46 million (2003 US Census), largely distributed among several cities, including Alameda, Berkeley, Fremont, Hayward, Newark, Oakland, San Leandro, San Lorenzo, and Union City. Major known tectonic structures in the East Bay area include the Hayward Fault and the Diablo Range to the east and a relatively deep sedimentary basin known as the San Leandro Basin beneath the eastern part of the bay. Known active faults, such as the Hayward, Calaveras, and San Andreas pose significant earthquake hazards to the region, and these and related faults also affect ground-water flow in the San Francisco Bay area. Because most of the valley comprising the San Francisco Bay area is covered by Holocene alluvium or water at the surface, our knowledge of the existence and locations of such faults, their potential hazards, and their effects on ground-water flow within the alluvial basins is incomplete. To better understand the subsurface stratigraphy and structures and their effects on ground-water and earthquake hazards, the U.S. Geological Survey (USGS), in cooperation with the East Bay Municipal Utility District (EBMUD), acquired a series of high-resolution seismic reflection and refraction profiles across the East Bay Plain near San Leandro in June 2002. In this report, we present results of the seismic imaging investigations, with emphasis on ground water.

  15. Cetacean Community Ecology in the Waters of Sri Lanka and the Bay of Bengal

    Science.gov (United States)

    2013-09-30

    water (e.g., Bay of Bengal), by evaporation and low river runoff (e.g., Arabian Sea), as well as coastal currents, eddy activity, and large-scale...Bay of Bengal. What little research has been done in the region has focused on the river dolphins and near- shore porpoises (e.g., Smith et al. 2008...area in the central Bay of Bengal and the waters of Sri Lanka, including ASIRI cruise transects and mooring lines. Light yellow lines indicate national EEZs. 5

  16. Record-high specific conductance and temperature in San Francisco Bay during water year 2014

    Science.gov (United States)

    Downing-Kunz, Maureen; Work, Paul; Shellenbarger, Gregory

    2015-11-18

    The U.S. Geological Survey (USGS) has operated a water-quality monitoring network in San Francisco Bay since the late 1980s (Buchanan and others, 2015). This network includes 19 stations in the bay; currently, 8 stations are in operation (fig. 1). All eight stations are equipped with specific conductance (which can be related to salinity) and water-temperature sensors that record measurements at 15-minute intervals. Water quality in the bay constantly changes with the ocean tides and with seasonal and interannual differences in river inflows. Our network was designed to observe and characterize some of these changes in the bay across space and over time. Our data demonstrated a high degree of variability both in specific conductance and temperature at time scales from tidal to annual and also revealed longer term changes that are likely to influence overall environmental health in the bay (San Francisco Estuary Institute, 2014). Figure 1. Locations of fixed water-quality monitoring stations in San Francisco Bay, California, for the 2014 water year (October 1, 2013 to September 30, 2014).

  17. THE WIND-RESPONSE OF CHIKUGO RIVER ORIGINATED WATER IN ISAHAYA BAY

    Science.gov (United States)

    Li, Hongyuan; Matsunaga, Nobuhiro

    The wind response of salinity structures in Isahaya Bay was investigated by using the data of wind and salinity measured by the Kyushu Regional Agricultural Administration Office. In Isahaya Bay, the south-southwest wind and north-northeast wind were prevailing in summer season. It is known that the fresh water discharged from Chikugo River is transported along the west coast of the inner area of Ariake Sea and reaches to the mouth of Isahaya Bay. When a large amount of fresh water is discharged from Chikugo River and the northerly wind is blowing for a long period, the strong salinity stratification appears in Isahaya Bay. It is caused by that the northerly wind accelerates the transport of the Chikugo River originated fresh water into Isahaya Bay. After that, the salinity stratification is gone with the blow of southerly wind. The data-analysis reveals that the salinity structure in Isahaya Bay depends strongly on the fresh water from the Chikugo River and the wind blowing over Ariake Sea.

  18. Effects of waves on water dispersion in a semi-enclosed estuarine bay

    Science.gov (United States)

    Delpey, M. T.; Ardhuin, F.; Otheguy, P.

    2012-04-01

    The bay of Saint Jean de Luz - Ciboure is a touristic destination located in the south west of France on the Basque coast. This small bay is 1.5km wide for 1km long. It is semi-enclosed by breakwaters, so that the area is mostly protected from waves except in its eastern part, where wave breaking is regularly observed over a shallow rock shelf. In the rest of the area the currents are generally weak. The bay receives fresh water inflows from two rivers. During intense raining events, the rivers can introduce pollutants in the bay. The input of pollutants combined with the low level dynamic of the area can affect the water quality for several days. To study such a phenomenon, mechanisms of water dispersion in the bay are investigated. The present paper focuses on the effects of waves on bay dynamics. Several field experiments were conducted in the area, combining wave and current measurements from a set of ADCP and ADV, lagrangian difter experiments in the surfzone, salinity and temperature profile measurements. An analysis of this set of various data is provided. It reveals that the bay combines remarkable density stratification due to fresh water inflows and occasionally intense wave-induced currents in the surfzone. These currents have a strong influence on river plume dynamics when the sea state is energetic. Moreover, modifications of hydrodynamics in the bay passes are found to be remarkably correlated with sea state evolutions. This result suggests a significant impact of waves on the bay flushing. To further analyse these phenomena, a three dimensional numerical model of bay hydrodynamics is developed. The model aims at reproducing fresh water inflows combined with wind-, tide- and wave-induced currents and mixing. The model of the bay is implemented using the code MOHID , which has been modified to allow the three dimensional representation of wave-current interactions proposed by Ardhuin et al. [2008b] . The circulation is forced by the wave field modelled

  19. Analysis of sediment, water, and biological samples from the Bay Farm Borrow Area, San Francisco Bay, California

    Energy Technology Data Exchange (ETDEWEB)

    Thom, R.M.; Lefkovitz, L.F. (Battelle/Marine Sciences Lab., Sequim, WA (United States))

    1991-08-01

    The Bay Farm Borrow Area (BFBA) of San Francisco Bay, California, is under consideration as a dredged-material disposal site by the US Army Corps of Engineers (USACE). As part of the analysis of the site, information is required on the quality of benthic biota, sediment, and water in the BFBA. The objective of this report was to provide data on infauna communities, sediment, and water chemistry from samples collected from the BFBA. The samples were collected, and the data will be analyzed by Science Applications International (SAIC). A total of four samples for sediment chemistry, four samples for water chemistry, and 7 samples for infauna communities were analyzed by the Battelle/Marine Sciences Laboratory (MSL). Water analyses included tests for dissolved organic carbon, total suspended solids, four metals, butyltins, polychlorinated biphenyls (PCBs), chlorinated pesticides, polynuclear aromatic hydrocarbons (PAHs), four phenols, and total phenol. Sediment samples were analyzed for percent solids, total organic carbon, total oil and grease, total petroleum hydrocarbons, grain size, 10 metals, butyltins, PCBs, chlorinated pesticides, PAHs, four phenols, and total phenol. The data along with controls and spike recovery analyses, are presented in tables, and the results are discussed in the text. The quality assurance/quality control criteria were met for the analyses as were the detection limits specified by the sponsor.

  20. Characteristics of Water and Sediment Exchange Between Yangtze Estuary and Hangzhou Bay

    Institute of Scientific and Technical Information of China (English)

    KONG Jun; SONG Zhi-yao; XIA Yun-feng; ZHANG Wei-sheng

    2007-01-01

    Based on the 2-D flow and sediment numerical model of the Yangtze Estuary and the Hangzhou Bay, the characteristics of water and sediment exchange in their joint waters is studied through quantitative calculation and analysis of the characteristics of water flow and sediment transportation. The results show that there is periodical water and sediment exchange in this joint waters, that the net water exchange appears mainly between 0~6 m depth (theoretical datum plane, the same below) offshore and the maximum is near the depth of 2 m, and that the net sediment exchange mainly appears between 0~5 m depth and the maximum is near the depth of 3 m, indicating that the range of water flow passage is different from that of sediment transport from the Yangtze Estuary to the Hangzhou Bay. Combined with the results of numerical simulation, this paper also analyzes the hydrodynamical mechanism influencing water and sediment exchange between the Yangtze Estuary and the Hangzhou Bay, including tidal fluctuation, tidal current kinetic energy, tide-induced residual current and the trace of water particles. Finally, the sediment transportation passage on the Nanhui tidal flat is discussed, and the results show that sediment is transported into the Hangzhou Bay from the south side of Shipilei, while sediment is brought back to the South Channel of the Yangtze Estuary from the north side.

  1. 78 FR 63972 - Notice of Proposed Methodology for the 2014 Delaware River and Bay Water Quality Assessment Report

    Science.gov (United States)

    2013-10-25

    ... COMMISSION Notice of Proposed Methodology for the 2014 Delaware River and Bay Water Quality Assessment Report... methodology proposed to be used in the 2014 Delaware River and Bay Water Quality Assessment Report is...: Comments will be accepted via email to john.yagecic@drbc.state.nj.us , with ``Water Quality Assessment 2014...

  2. 76 FR 50188 - Notice of Proposed Methodology for the Delaware River and Bay Integrated List Water Quality...

    Science.gov (United States)

    2011-08-12

    ... COMMISSION Notice of Proposed Methodology for the Delaware River and Bay Integrated List Water Quality... methodology proposed to be used in the 2012 Delaware River and Bay Integrated List Water Quality Assessment is... to 609-883-9522; by U.S. Mail to DRBC, Attn: Water Quality Assessment 2012, P.O. Box 7360, West...

  3. Chesapeake Bay Future Conditions Report. Volume 6. Water Quality

    Science.gov (United States)

    1977-12-01

    and paper industries for example, lingosulfates or pulp wastes can be synthesized to produce artificial vanilla flavoring and other valuable acetic...Plants in the Chesapeake Bay Area. Ozone is a blue, pungent smelling, unstable gas existing as an oxidized form of oxygen. Disinfec- tion by ozonation is

  4. 33 CFR 334.70 - Buzzards Bay, and adjacent waters, Mass.; danger zones for naval operations.

    Science.gov (United States)

    2010-07-01

    ..., Mass.; danger zones for naval operations. 334.70 Section 334.70 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.70 Buzzards Bay, and adjacent waters, Mass.; danger zones for naval operations. (a)...

  5. Numerical Study of the Effect of a Power Plant Cooling Water Discharge in the Montevideo Bay

    Directory of Open Access Journals (Sweden)

    Mónica Fossati

    2011-01-01

    Full Text Available The numerical simulation of the water temperature in the Río de la Plata River and Montevideo's Bay was done using the numerical model of finite elements RMA-10 in its 2D vertical integrated mode. Parameters involved in the formulations of thermal exchange with the atmosphere were adjusted using measurements of water temperature in several locations of the water body. After calibrating the model, it was used to represent the operation of a power plant located in Montevideo's Bay. This central takes water from the bay in order to cool its generators and also discharges high-temperature water into the bay. The correct representation of temperatures at the water intake and discharge of the plant reflects that the model is able to represent the operation of the central. Several analysis were made to study the thermal plume, the effects of the water discharge on the water intake of the power plant, and the effect on environmental variables of the study area like currents.

  6. Iodate in inshore and offshore waters of Central Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.

    Biological stripping of iodate in the surface waters is noticed in the inshore and offshore waters of Bay of Bengal. A good correlation is observed between iodate and phosphate and nitrate and the molar ratios determined being NO3: PO4: IO3 = 88...

  7. A Three-Dimensional Water Quality Model and Its Application to Jiaozhou Bay, China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan; SUN Ying-lan; YU Jing; YUAN Dao-wei; ZHANG Rui-jin

    2012-01-01

    A three-dimensional coupled physical and water quality model was developed and applied to the Jiaozhou Bay to study water quality involving nutrients,biochemical oxygen demand,dissolved oxygen,and phytoplankton that are closely related to eutrophication process.The physical model is a modified ECOM-si version with inclusion of flooding/draining processes over the intertidal zone.The water quality model is based on WASP5 which quantifies processes governing internal nutrients cycling,dissolved oxygen balance and phytoplankton growth.The model was used to simulate the spatial distribution and the temporal variation of water quality in the Jiaozhou Bay for the period of May 2005 to May 2006.In addition,the effect of reduction of riverine nutrients load was simulated and evaluated.The simulated results show that under the influence of nutrients discharged from river,the concentrations of nutrients and phytoplankton were higher in the northwest and northeast of the bay,and decreased from the inner bay to the outer.Affected by strong tidal mixing,the concentrations of all state variables were vertically homogeneous except in the deeper regions where a small gradient was found.Obvious seasonal variation of phytoplankton biomass was found,which exhibited two peaks in March and July,respectively.The variation of riverine waste loads had remarkable impact on nutrients concentration in coastal areas,but slightly altered the distribution in the center of the bay.

  8. DISTRIBUTION AND COMPOSITION OF PAHs IN SURFACE WATERS,POREWATER AND SEDIMENTS FROM XIAMEN WESTERN BAY

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Xiamen Western Bay's water and sediment quality were studied by determining the levels of sixteen polycyclic aromatic hydrocarbons (PAHs) in water, porewater and sediment samples from nine locations in the bay. Total PAH concentrations varied from 106 to 945 ng/l in water, below detection to 3548 ng/l in porewater, and 247 to 480 ng/g dry weight in surface sediments. PAHs levels in porewater were higher than those in surface water, due to the preference of these hydrophobic compounds for sedimentary phase instead of water. Such a concentration gradient implies a potential flux of pollutants from sediments to overlying water. The PAHs levels in sediments were one to several orders of magnitude lower than those in 1993, suggesting their decreased input in recent years and possible degradation with time.

  9. Water quality of the inner Puno Bay, Titicaca Lake, during summer 2011

    Directory of Open Access Journals (Sweden)

    Diana F. Beltrán Farfán

    2015-12-01

    Full Text Available Water quality of the inner Puno Bay was evaluated; we established 12 stations, and were assessed monthly from December 2010 to April 2011. Physicochemical water parameters were determined with EPA and APHA standard methods. Nutrients were determined spectrophotometrically. The parameters of temperature, dissolved oxygen, pH, phosphates, nitrates and nitrites of water show that the outlet of the stabilization lagoon of Puno City (Espinar Island is a critical area of contamination at the inner Puno Bay. Transparency values were low. The electrical conductivity of water showed high values. Alkalinity values were high (75 - 150 mg/L and very high (> 150 mg/L, indicating a high content of carbonates and bicarbonates. Water hardness were high (121-180 mg/L and very high (> 180 mg/L. High levels of fecal coliform in waters near the island Espinar would be the result of wastewater discharges from the Puno city, without proper treatment.

  10. Increasing Hydrogen Ion Activity of Water in Two Reservoirs Supplying the San Francisco Bay Area, California

    Science.gov (United States)

    McColl, J. G.

    1981-10-01

    The hydrogen ion activity (H+) of water in two Sierra Nevada reservoirs (Pardee and Hetch Hetchy) that supply the San Francisco Bay area has been increasing with time over the period 1954-1979. This conclusion is based on weekly measurements ofpH at the two reservoirs and is supported by measurements of alkalinity which decreased at Pardee over the period 1944-1979. Based on linear models, the rate of the increasing (H+) was the same at both reservoirs, and (H+) varied concomitantly from year to year, suggesting a common, general cause. Mean monthly variation in (H+) corresponded to mean monthly variation in atmospheric pollution from a nine-county area around San Francisco Bay. The most likely cause of the increasing (H+) of reservoir waters is NOx from automobile exhausts primarily from the San Francisco Bay area.

  11. Relation Matrix of Water Exchange for Sea Bays and Its Application

    Institute of Scientific and Technical Information of China (English)

    SUN Jian; TAO Jian-hua

    2006-01-01

    Water exchange is an important hydrodynamic character of sea bays, and it is the basis for the study of the environmental capacity of sea bays. In this paper, a relation matrix is set up to describe the interaction among different areas of a sea bay, and to predict the water quality of those areas. The relation matrix is calculated based on the numerical results from a water quality model. This method is applied to the study of water exchange and the prediction of water quality of the Bohai Sea. The Bohai Sea is divided into five areas, and the effect of seasonal wind is taken into consideration. The results show a) the relation matrix can be used to study the water exchange among different areas and predict water quality of different areas at the respective characteristic time, b) the reduction of pollutant is dependent on both water exchange and initial distribution of the pollutant, and c) the half-life time of the pollutant is longer than the half-exchange time of the sea water.

  12. Ground water discharge and the related nutrient and trace metal fluxes into Quincy Bay, Massachusetts

    Science.gov (United States)

    Poppe, L.J.; Moffett, A.M.

    1993-01-01

    Measurement of the rate and direction of ground water flow beneath Wollaston Beach, Quincy, Massachusetts by use of a heat-pulsing flowmeter shows a mean velocity in the bulk sediment of 40 cm d-1. The estimated total discharge of ground water into Quincy Bay during October 1990 was 1324-2177 m3 d-1, a relatively low ground Water discharge rate. The tides have only a moderate effect on the rate and direction of this flow. Other important controls on the rate and volume of ground water flow are the limited thickness, geographic extent, and permeability of the aquifer. Comparisons of published streamflow data and estimates of ground water discharge indicate that ground water makes up between 7.4-12.1% of the gaged freshwater input into Quincy Bay. The data from this study suggest the ground water discharge is a less important recharge component to Quincy Bay than predicted by National Urban Runoff Program (NURP) models. The high nitrate and low nitrite and ammonia concentrations in the ground water at the backshore we]l sites and low nitrate and high nitrite and ammonia concentrations in the water flowing from the foreshore suggests that denitrification is active in the sediments. The low ground water flow rates and low nitrate concentrations in the foreshore samples suggest that little or no nitrate is surviving the denitrification process to affect the planktonic community. Similarly, oxidizing conditions in the aquifer and low trace metal concentrations in the ground water samples suggest that the metals may be precipitating and binding to sedimentary phases before impacting the bay.

  13. Immediate effect of simulated sand mining on the variation of bacterial parameters in coastal waters of Kalbadevi Bay, Ratnagiri

    Digital Repository Service at National Institute of Oceanography (India)

    Fernandes, C.E.G.; Das, A.; Naik, S.S.; Sharma, R.; LokaBharathi, P.A.

    The variation in bacterial parameters of coastal waters and sediments of Kalbadevi Bay, Ratnagiri, Maharashtra, India was examined for immediate response after simulated mining. Sampling was carried out at suction and disturbance points in the water...

  14. Distribution of perfluoroalkyl compounds in Osaka Bay and coastal waters of Western Japan.

    Science.gov (United States)

    Beškoski, Vladimir P; Yamamoto, Katsuya; Yamamoto, Atsushi; Okamura, Hideo; Hayashi, Mitsuru; Nakano, Takeshi; Matsumura, Chisato; Fukushi, Keiichi; Wada, Shinpei; Inui, Hideyuki

    2017-03-01

    Perfluoroalkyl acids (PFAAs) including perfluoroalkyl sulfonates (PFSAs) and perfluoroalkyl carboxylates (PFCAs) were analyzed in sediment samples taken from Ajifu Waterway in Osaka city, from Osaka Bay, and from Kagoshima Bay, as well as in fifteen seawater samples collected from Osaka Bay and coastal waters of Western Japan. In all sediment samples, only PFCAs were detected, and the highest concentration was determined in Ajifu Waterway, where ΣPFAA was 58990 ng kg(-1) dry weight. The total concentrations of PFAAs in sea water samples ranged between the limit of quantification and 53.4 ng L(-1), and perfluorohexanoic acid was the most prevalent and had the highest concentration of 37 ng L(-1). The changes in the patterns and concentrations of PFAAs in Osaka Bay and coastal waters of Western Japan indicate that the PFAAs in surface waters are influenced by sources from Keihanshin Metropolitan Area, mainly the Yodo River basin, and the dilution effect which naturally occurs during their transport to the Pacific Ocean.

  15. Bio-optical water quality dynamics observed from MERIS in Pensacola Bay, Florida

    Science.gov (United States)

    Observed bio-optical water quality data collected from 2009 to 2011 in Pensacola Bay, Florida were used to develop empirical remote sensing retrieval algorithms for chlorophyll a (Chla), colored dissolved organic matter (CDOM), and suspended particulate matter (SPM). Time-series ...

  16. Different stages of Cd’s transporting process in waters in Jiaozhou Bay

    Science.gov (United States)

    Yang, Dongfang; Miao, Zhenqing; Li, Haixia; Zhang, Longlei; Wang, Qi

    2017-08-01

    Cd pollution in marine bays is one of the critical environmental issues, and understanding the stages of transporting process of Cd in marine bays is essential to pollution control. This paper analyzed the stages of Cd’s transporting process in waters in Jiaozhou Bay during 1979-1983. Results showed that the transporting process in waters in Jiaozhou Bay included seven different stages of 1) the sedimentation of Cd content was beginning, 2) the sedimentation of Cd content was increasing, 3) the sedimentation of Cd content was increasing greatly, 4) the sedimentation of Cd content was beginning to decrease, 5) the sedimentation of Cd content was decreasing stably, 6) the sedimentation of Cd content was beginning to stop, and 7) the sedimentation of Cd content was beginning to fully stop. In according to the different stages of Cd’s transporting process in waters, the changing trends of Cd contents in surface and bottom waters and their relationships could be defined and predicted.

  17. Importance of shallow-water bay biotopes as nurseries for Caribbean reef fishes

    NARCIS (Netherlands)

    Nagelkerken, I.A.

    2000-01-01

    Mangroves and seagrass beds can harbour high densities of mostly juvenile fishes. It has therefore long been assumed that these habitats function as nursery areas. In the present thesis the nursery function of mangroves, seagrass beds and other shallow-water biotopes, located in sheltered inland bay

  18. Bio-optical water quality dynamics observed from MERIS in Pensacola Bay, Florida

    Science.gov (United States)

    Observed bio-optical water quality data collected from 2009 to 2011 in Pensacola Bay, Florida were used to develop empirical remote sensing retrieval algorithms for chlorophyll a (Chla), colored dissolved organic matter (CDOM), and suspended particulate matter (SPM). Time-series ...

  19. Water renewal in Montevideo's bay: a two compartments model for tritium kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Suarez-Antola, Roberto, E-mail: rsuarez@ucu.edu.uy [Universidad Catolica del Uruguay (UCU), Montevideo (Uruguay)

    2013-07-01

    During field work about dynamics and renewal of water in Montevideo's Bay, 100 Ci of tritiated water were evenly distributed in the north-east region of the bay, by a continuous injection of a solution, during 5 hours, from a 200 litres tank, using a peristaltic pump. The whole bay was divided in 20 concentration cells, taking into account available bathymetric charts and corrections from field data obtained in situ. Tritium concentrations (activities per unit volume) and other relevant parameters (temperature, electrical conductivity, etc.) were measured in vertical profiles during three weeks, in the mid-point of each cell, first twice a day and the on a daily basis. Remnant total tritium activity was estimated from cells volumes and midpoint cells activity concentrations. Consistency checks were done. A one compartment model was used to estimate a global renewal time of circa 29 hours. However, the details of the measured tritium kinetics, a careful consideration of bathymetric data, water movements in a tidal environment (measured with drogues, fluorescent tracers and current meters), as well as the results of computer fluid dynamics modelling (in depth averaged) suggests that the bay can be meaningfully divided in two main compartments: a North-East and a South-West compartment. The purpose of this paper is threefold: (1) to describe the construction of a two compartments model for water renewal in Montevideo's Bay, (2) to apply experimental data of tritium kinetics to estimate the parameters of the model, and (3) to discuss the validity of the model and its practical applicability. The meaning of the renewal time of each compartment and its relation with the measured tritium kinetics in each cell is discussed. The perturbations in water circulation and renewal produced by civil works already done or the perturbations that could be expected due to civil works to be done, in relation with Montevideo's harbour, is discussed. The tracer model

  20. Chesapeake Bay Water Quality Monitoring Using Satellite Imagery Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Work done at Water Resources Center, University of Minnesota has demonstrated the feasibility of performing regional assessment of lake water quality using Landsat...

  1. Benthic flux of dissolved nickel into the water column of south San Francisco Bay

    Science.gov (United States)

    Topping, B.R.; Kuwabara, J.S.; Parcheso, Francis; Hager, S.W.; Arnsberg, A.J.; Murphy, Fred

    2001-01-01

    Field and laboratory studies were conducted between April, 1998 and May, 1999 to provide the first direct measurements of the benthic flux of dissolved (0.2-micron filtered) nickel between the bottom sediment and water column at three sites in the southern component of San Francisco Bay (South Bay), California. Dissolved nickel and predominant ligands (represented by dissolved organic carbon, and sulfides) were the solutes of primary interest, although a variety of ancillary measurements were also performed to provide a framework for interpretation. Results described herein integrate information needs identified by the State Water Resources Control Board and local stakeholders with fundamental research associated with the U.S. Geological Survey Toxic Substances Hydrology Program. Dissolved-Ni concentrations in the bottom water over the three sampling dates ranged from 34 to 43 nanomoles per liter. Dissolved-macronutrient concentrations in the bottom water were consistently higher (frequently by orders of magnitude) than surface-water determinations reported for similar times and locations (Regional Monitoring Program, 2001). This is consistent with measured positive benthic fluxes for the macronutrients. Benthic-flux estimates for dissolved nickel from core-incubations, when areally averaged over the South Bay, were significant (that is, of equivalent or greater order of magnitude) relative to previously reported freshwater point and non-point sources. This observation is consistent with previous determinations for other metals, and with the potential remobilization of sediment-associated metals that have been ubiquitously distributed in the South Bay. Similar to dissolved-nickel results, benthic flux of macronutrients was also consistently significant relative to surface-water inputs. These results add to a growing body of knowledge that strongly suggests a need to consider contaminant transport across the sediment-water interface when establishing future

  2. 36 CFR 13.1130 - Is commercial fishing authorized in the marine waters of Glacier Bay National Park?

    Science.gov (United States)

    2010-07-01

    ... authorized in the marine waters of Glacier Bay National Park? 13.1130 Section 13.1130 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR NATIONAL PARK SYSTEM UNITS IN ALASKA Special Regulations-Glacier Bay National Park and Preserve Commercial Fishing § 13.1130 Is...

  3. Bacterial productivity in the Prydz Bay and its adjacent waters,Antarctic

    Institute of Scientific and Technical Information of China (English)

    邱雨生; 黄奕普; 陈敏; 刘广山

    2004-01-01

    Bacterial productivity was measured using 3H-thymidine methods in the Prydz Bay and its adjacent waters in the Southern Ocean during the 16th National Antarctic Research Expedition of China (CHINARE). The results showed that bacteted for the Ross Sea. The mean ratio of bacterial productivity to primary productivity in our study areas was 41%. The general characteristics in the vertical profiles showed a subsurface maximum at most of the stations, which was also consistent with those observed in the other sea areas in the Southern Ocean. The spatial distribution of bacterial productivity and dissolved organic carbon in the surface waters showed that their variations were inversely correlative. The relationship among bacterial productivity, primary productivity and dissolved organic carbon suggested that bacterial productivity in the Prydz Bay and its adjacent water was influenced mostly by phytoplankton activities and the hydrologic conditions.

  4. Polycyclic aromatic hydrocarbon pollution in the surface water and sediments of Chabahar Bay, Oman Sea.

    Science.gov (United States)

    Agah, Homira; Mehdinia, Ali; Bastami, Kazem Darvish; Rahmanpour, Shirin

    2017-02-15

    In the present study, the concentrations and distribution of 16 polycyclic aromatic hydrocarbons (PAHs) in the water and surface sediments from the Chabahar Bay, Oman Sea, were investigated in May (premonsoon) and December (postmonsoon) 2012. The concentrations of PAHs in the surface water samples ranged from 1.7 to 2.8ngl(-1) and from 0.04 to 59.6ngl(-1) in pre- and postmonsoon, respectively. In general, the PAH levels of the water samples from Chabahar Bay were higher in postmonsoon than in premonsoon (p<0.05). The concentrations of PAHs in the sediment samples varied from undetectable levels to 92.8ngg(-1) d.w. in both seasons. The seasonal comparison of the results in sediment samples showed that the overall concentration of PAH compounds was higher in the postmonsoon season (p<0.05).

  5. Tap water isotopes reveal the San Francisco Bay Area's plumbing and responses to a major drought

    Science.gov (United States)

    Tipple, B. J.; Jameel, M. Y.; Chau, T. H.; Mancuso, C. J.; Bowen, G. J.; Dufour, A.; Chesson, L. A.; Ehleringer, J. R.

    2016-12-01

    Water availability and sustainability in the Western United States is a major flashpoint among expanding communities, growing industries, and productive agricultural lands. This issue came to a head in 2015 in the State of California, when the State mandated a 25% reduction in urban water use following a multi-year drought that significantly depleted water resources. The demands for and challenges in supplying water are only expected to intensify as climate perturbations, such as the 2012-2015 California Drought, become more common. As a consequence, there is an increased need to understand linkages between population centers, water transport and usage, and the impacts of climate change on water resources and infrastructure. To better understand these relationships within a megalopolis in the Western United States, we collected and analyzed 723 tap waters from the San Francisco Bay Area during seven collection campaigns across 21 months during 2013-2015. San Francisco Bay Area was selected as it has well-known water management strategies and its water resources were dramatically affected by the 2012-2105 drought. Consistent with known water management strategies and previous reports of tap water isotope values, we found large spatiotemporal variations in the δ2H and δ18O values of tap waters, indicative of complex water transport systems and municipality-scale management decisions. We observed δ2H and δ18O values of tap water consistent with waters originating from snowmelt from the Sierra Nevada Mountains, local precipitation, ground water, and partially evaporated reservoir sources. A cluster analysis of measured tap water data grouped waters from 43 static sampling sites that were associated with specific water utility providers within the San Francisco Bay Area and known management practices. Water management responses to the drought, such as source switching, bringing in new sources, and conservation, could be observed within the isotope data from each of

  6. Continuous water-quality and suspended-sediment transport monitoring in the San Francisco Bay, California, water years 2011-13

    Science.gov (United States)

    Buchanan, Paul A.; Downing-Kunz, Maureen A.; Schoellhamer, David H.; Shellenbarger, Gregory; Weidich, Kurt W.

    2014-01-01

    The U.S. Geological Survey (USGS) monitors water quality and suspended-sediment transport in the San Francisco Bay. The San Francisco Bay area is home to millions of people, and the bay teems with both resident and migratory wildlife, plants, and fish. Fresh water mixes with salt water in the bay, which is subject both to riverine and marine (tides, waves, influx of salt water) influences. To understand this environment, the USGS, along with its partners, has been monitoring the bay’s waters continuously since 1988. Several water-quality variables are of particular importance to State and Federal resource managers and are monitored at key locations throughout the bay. Salinity, which indicates the relative mixing of fresh and ocean waters in the bay, is derived from specific conductance measurements. Water temperature, along with salinity, affects the density of water, which causes gravity driven circulation patterns and stratification in the water column. Turbidity is measured using light-scattering from suspended solids in water, and is used as a surrogate for suspended-sediment concentration (SSC). Suspended sediment often carries adsorbed contaminants; attenuates sunlight in the water column; deposits on tidal marsh and intertidal mudflats, which can help sustain these habitats as sea level rises; and deposits in ports and shipping channels, which can necessitate dredging. Dissolved oxygen, which is essential to a healthy ecosystem, is a fundamental indicator of water quality, and its concentration is affected by water temperature, salinity, ecosystem metabolism, tidal currents, and wind. Tidal currents in the bay reverse four times a day, and wind direction and intensity typically change on a daily cycle: consequently, salinity, water temperature, suspendedsediment concentration, and dissolvedoxygen concentration vary spatially and temporally throughout the bay, and continuous measurements are needed to observe these changes. The purpose of this fact sheet

  7. Tracing water and suspended matter in Raritan and Lower New York Bays using dissolved and particulate elemental concentrations

    Science.gov (United States)

    Paulson, A.J.

    2005-01-01

    Geochemical tracers were used to examine the mixing of water and particles in Lower New York and Raritan Bays in August 1999 during low-flow conditions. Four brackish water masses (20 ≤ S ≤ 28) originating in the Raritan and Shrewsbury Rivers, Arthur Kill, and Upper New York Bay were characterized by their dissolved metals concentrations. The mixing lines of dissolved Cu, Ni, and Pb in Lower New York Bay were similar to those in Upper New York Bay, the source of most of the freshwater to the system. Dissolved Cd and Mn seemed to have been removed by particles in several regions of the study. Dissolved Cu, Ni and Pb in the Raritan River fell below the mixing lines of the Lower New York Bay. In contrast, the concentrations of dissolved Co and Mn in the Raritan River were distinctly higher than those in the Lower New York Bay, while dissolved Cu and Ni were elevated in the Arthur Kill. A plot of dissolved Co versus dissolved Ni clearly differentiated among three water masses: (1) Upper and Lower New York Bays and Sandy Hood Bay, (2) the Raritan River, and (3) Arthur Kill–Raritan Bay–Shrewsbury River.

  8. Cetacean Presence in the Trincomalee Bay and Adjacent Waters, Sri Lanka

    Directory of Open Access Journals (Sweden)

    Ranil P. Nanayakkara

    2014-01-01

    Full Text Available In Sri Lanka thirty species of cetaceans have been recorded to date. The canyon at Trincomalee bay is a multiple submarine canyon complex and anecdotal reports suggest that the Trincomalee bay and its adjacent waters are utilised by a number of cetacean species. Though Cetaceans are known to be abundant in the waters off Trincomalee there is a dearth of research and data pertaining to the abundance and species frequenting the Trincomalee bay and its adjacent waters. As such the current study was initiated, to get a consensus of the abundance and occurrences of species in Trincomalee Bay and its adjacent waters. Field surveys were carried out for 19 months and the research platform was a 35-foot commercial fishing vessel. 177 cetacean encounters were recorded on 67 of the 75 field days. Remarkably a total of 11 species of cetaceans which composed of two species of Baleen Whales and nine species of Toothed Whales were recorded. Delphinidae was the most common family recorded, followed by Balaenopteridae, Ziphiidae, Physeteridae, and Kogiidae. Spinner Dolphins were the most abundant cetacean owing to the large pods observed and the regularity of the sightings. They were the only species seen feeding/traveling with birds and fish (tuna. Sperm Whales, Blue Whales, and Bryde’s Whales were also relatively common. Two records of interspecific association between cetaceans were recorded. The increase in the human population in the study area has resulted in the overexploitation of marine resources which has dire repercussions on the marine mammal communities found in these waters.

  9. USGS measurements of water quality in San Francisco Bay (CA), 1969-2015

    Science.gov (United States)

    Cloern, James E.; Schraga, Tara

    2016-01-01

    The U.S. Geological Survey maintains a program of water-quality studies in San Francisco Bay (CA) that began in 1969. This Data Release makes available all measurements made from 1969 through 2015. Water-quality constituents include salinity, temperature, light attenuation coefficient, and concentrations of chlorophyll-a, dissolved oxygen, suspended particulate matter, nitrate, nitrite, ammonium, silicate and phosphate. Water samples are collected at 37 fixed sampling locations along a 145-km transect from lower South San Francisco Bayo to the lower Sacramento River. A map of sampling locations is available on the project website at: https://sfbay.wr.usgs.gov/access/wqdata/overview/wherewhen/stnmap.html.

  10. Spatial and seasonal patterns of ichthyoplankton assemblages in the Haizhou Bay and its adjacent waters of China

    Science.gov (United States)

    Li, Zengguang; Ye, Zhenjiang; Wan, Rong

    2015-12-01

    Surveys were conducted in five voyages in Haizhou Bay and its adjacent coastal area from March to December 2011 during full moon spring tides. The ichthyoplankton assemblages and the environmental factors that affect their spatial and seasonal patterns were determined. Totally 35 and 12 fish egg and larvae taxa were identified, respectively. Over the past several decades, the egg and larval species composition has significantly changed in Haizhou Bay and its adjacent waters, most likely corresponding with the alteration of fishery resources, which are strongly affected by anthropogenic activities and climate change. The Bray-Curtis dissimilarity index identified four assemblages: near-shore bay assemblage, middle bay assemblage and two closely related assemblages (near-shore/middle bay assemblage and middle/edge of bay assemblage). The primary species of each assemblage principally reflected the spawning strategies of adult fish. The near-shore bay assemblage generally occurred in near-shore bay, with depths measuring biological behavioral traits and oceanographic features, particularly the variation of local conditions within the constraint of a general reproductive strategy. The results of Spearman's rank correlation analysis indicated that both fish egg and larval abundance were positively correlated with depth, which is critical to the oceanographic features in Haizhou Bay.

  11. Intrusion of the Bay of Bengal water into the Arabian Sea during winter monsoon and associated chemical and biological response

    Digital Repository Service at National Institute of Oceanography (India)

    PrasannaKumar, S.; Narvekar, J.; Kumar, A.; Shaji, C.; Anand, P.; Sabu, P.; Rijomon, G.; Josia, J.; Jayaraj, K.A.; Radhika, A.; Nair, K.K.C.

    Coastal Current carrying low salinity waters from the northern Bay feeds into the West India Coastal Current flowing north along the shelf in the Arabian Sea. Advection of nutrients by this intrusion triggers enhanced levels of chlorophyll near...

  12. Windward Community College Heeia Stream and Kaneohe Bay Water Quality Assessment Project 2004-2005 (NODC Accession 0002449)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Measurements of water quality parameters were taken by Windward Community College faculty and students at eight sites in the Heeia Stream and adjacent Kaneohe Bay...

  13. Cathodic protection of mild steel and copper in deep waters of the Arabian Sea and Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sawant, S.S.; Venkat, K.; Wagh, A.B.

    Performance of cathodic protection system to mild steel and copper in deep (> 1000 m) oceanic waters of the Arabian Sea and Bay of Bengal has been assessed using aluminium and mild steel sacrificial anodes. The corrosion rates of unprotected metals...

  14. Quantifying groundwater’s role in delaying improvements to Chesapeake Bay water quality

    Science.gov (United States)

    Sanford, Ward E.; Pope, Jason P.

    2013-01-01

    A study has been undertaken to determine the time required for the effects of nitrogen-reducing best management practices (BMPs) implemented at the land surface to reach the Chesapeake Bay via groundwater transport to streams. To accomplish this, a nitrogen mass-balance regression (NMBR) model was developed and applied to seven watersheds on the Delmarva Peninsula. The model included the distribution of groundwater return times obtained from a regional groundwater-flow (GWF) model, the history of nitrogen application at the land surface over the last century, and parameters that account for denitrification. The model was (1) able to reproduce nitrate concentrations in streams and wells over time, including a recent decline in the rate at which concentrations have been increasing, and (2) used to forecast future nitrogen delivery from the Delmarva Peninsula to the Bay given different scenarios of nitrogen load reduction to the water table. The relatively deep porous aquifers of the Delmarva yield longer groundwater return times than those reported earlier for western parts of the Bay watershed. Accordingly, several decades will be required to see the full effects of current and future BMPs. The magnitude of this time lag is critical information for Chesapeake Bay watershed managers and stakeholders.

  15. Evaluation of coastal waters receiving fish processing waste: Lota Bay as a case study.

    Science.gov (United States)

    Ahumada, Ramón; Rudolph, Anny; Contreras, Sergio

    2004-01-01

    Liquid wastes from the fish meal and oil processing industries produce serious environmental impacts in coastal embayments on the coasts of Chile and Peru. This article presents an analysis of an environmental monitoring program at Lota Bay, a shallow coastal indentation in central Chile (37 degrees S) exposed to industrial fishing activity. The study of the environmental impact produced by waste effluents permitted making an evaluation of the bay's capacity for seasonal recovery from this impact. Seasonal cruises were carried out during 1994 and in 1996, 1997, and 1998. Variables analyzed included salinity, temperature, dissolved oxygen, ammonium concentration and surface oil and grease. The hydrographic regime of Lota Bay follows a seasonal pattern, where, typical of most SE pacific embayments, waters from subsuperficial oxygen minimum zones moved into the bay. The percentages of dissolved oxygen were critical in the area of organic waste discharge. The impact of wastewater is related to the type and status of the fishery, including: (i) overloads of plant production lines, (ii) maintenance and cleaning of installations, and (iii) degree of shipboard fishing conservation. Major alterations were observed in summer, when the highest discharge of organic load occurred. In winter, an improvement in the re-aeration conditions reduced the impact. Remedial measures implemented beginning in 1997 arose from the monitoring program and had to be separated into two recovery factors including (a) internal management of plants and (b) treatment of plant effluents.

  16. Cetacean Community Ecology in the Waters of Sri Lanka and the Bay of Bengal

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Cetacean Community Ecology in the Waters of Sri Lanka...novaeangliae in the Arabian Sea. Marine Ecology Progress Series 149:13-21. Smith, B. D., B. Ahmed, R. M. Mowgli and S. Strindberg. 2008. Species occurrence...and distributional ecology of nearshore cetaceans in the Bay of Bengal, Bangladesh, with abundance estimates for Irrawaddy dolphins Orcaella

  17. Variability of the Continental Water Boundary near the Prydz Bay

    Institute of Scientific and Technical Information of China (English)

    Pu Shuzhen; Dong Zhaoqian; Hu Xiaomin; Yu Fei; Zhao Xin

    2002-01-01

    Based on the Data Obtained during the 15th Antarctic Expedition of Chian between November 1998 and February 1999,the paper discusses the water masses distributed on both sides of the Continental Water Boundary ( CWB) as well as the spacial variability of the physical characteristics of the central location, the frontal width, the frontal strength, the vertical depth, and the vertical thickness for CWB. The above results are compared with the results from the data obtained during the 9th Antarctic Expedition of China between December 1992 and February 1993, and the temporal variability of those characteristics is discussed. In addition, the inhomogeneity of the kinematic characteristics and the patterns of the dynamic heights for those water masses located on both sides of CWB are illustrated. As it is pointed out in the paper, the trough in the dynamic height field is identified with the frontal location of CWB and the oceanic current shear. Furthermore, the dynamic reason for the upwelling of the circumpolar deep water can be understood by the explanation described in the paper.

  18. Presence of selected chemicals of emerging concern in water and bottom sediment from the St. Louis River, St. Louis Bay, and Superior Bay, Minnesota and Wisconsin, 2010

    Science.gov (United States)

    Christensen, Victoria G.; Lee, Kathy E.; Kieta, Kristen A.; Elliott, Sarah M.

    2012-01-01

    The St. Louis Bay of Lake Superior receives substantial urban runoff, wastewater treatment plant effluent, and industrial effluent. In 1987, the International Joint Commission designated the St. Louis Bay portion of the lower St. Louis River as one of the Great Lakes Areas of Concern. Concerns exist about the potential effects of chemicals of emerging concern on aquatic biota because many of these chemicals, including endocrine active chemicals, have been shown to affect the endocrine systems of fish. To determine the occurrence of chemicals of emerging concern in the St. Louis River, the St. Louis Bay, and Superior Bay, the U.S. Geological Survey in cooperation with the Minnesota Pollution Control Agency and the Wisconsin Department of Natural Resources collected water and bottom-sediment samples from 40 sites from August through October 2010. The objectives of this study were to (1) identify the extent to which chemicals of emerging concern, including pharmaceuticals, hormones, and other organic chemicals, occur in the St. Louis River, St. Louis Bay, and Superior Bay, and (2) identify the extent to which the chemicals may have accumulated in bottom sediment of the study area. Samples were analyzed for selected wastewater indicators, hormones, sterols, bisphenol A, and human-health pharmaceuticals. During this study, 33 of 89 chemicals of emerging concern were detected among all water samples collected and 56 of 104 chemicals of emerging concern were detected in bottom-sediment samples. The chemical N,N-diethyl-meta-toluamide (DEET) was the most commonly detected chemical in water samples and 2,6-dimethylnaphthalene was the most commonly detected chemical in bottom-sediment samples. In general, chemicals of emerging concern were detected at a higher frequency in bottom-sediment samples than in water samples. Estrone (a steroid hormone) and hexahydrohexamethyl cyclopentabensopyran (a synthetic fragrance) were the most commonly detected endocrine active chemicals in

  19. Research on Hydrodynamic Force Enhancement and Water Environment Protection Measures of Dachan Bay, Shenzhen

    Directory of Open Access Journals (Sweden)

    Lv Wenbin

    2015-01-01

    Full Text Available With the research purpose of protection of water environmental quality in Dachan Bay Area in Shenzhen City, especially in National Development Zone in Qianhai Area, this paper establishes a horizontal two-dimensional water quality model of Dachan Bay and its branches by the use of WQ Module of Delft 3D. And this paper respectively simulates distribution of water quality in full high flow year, normal flow year and low flow year before and after the implementation of protection measures, predicts the effect of the water environment protection measures and focuses on the analysis of two kinds of hydrodynamic force enhancement pat-terns, that is, “water replenishing in dead zones” and “pollution discharge at back doors”, and finally recommends water environment protection measures with the core of “pollution discharge at back gates” by taking full advantage of natural dynamic, thus obtaining a better effect than that of the traditional “water replenishing in dead zones”.

  20. Distribution and origin of biologically available phosphorus in the water of the Meiliang Bay in summer

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The investigation and continuous monitoring with an innovative iron oxide embedded cellulose acetate membrane (FeO/CAM) on the concentrations of biologically available phosphorus (BAP) were conducted in the Meiliang Bay of the Taihu Lake during summer in 2004. The results showed that the concentrations of dissolved (FeO-DP), particulate (FeO-PP) and total bioavailable phosphorus (FeO-P) had similar horizontal distribution. The BAP concentrations were the highest in those estuaries in the northern bay. With the decrease of the distance to the estuary or long shore,there was little difference between BAP concentrations in an open lake area. During the observation period, algal blooms occurred in most waters of the northern bay, which was reflected from the high concentrations of chlorophyll a (Chl-a). While they were not highest in the estuarine waters of those major rivers, this is the case for the BAP concentrations. The concentrations of Chl-a had a significantly positive correlation with those of bioavailable phosphorus in the open area of the Meiliang Bay.With the sediment resuspension induced by wind and wave, BAP concentrations increased in a short-term, indicating that the riverine P inputs mainly contribute to the concentrations of BAP in the estuarine water while internal P release was the major source of BAP in the open lake area. In the eutrophic shallow lake, the blooms of alga may cause pH increase and further result in internal P release. The above results showed that the new membrane of FeO/CAM can be used to monitor the concentrations of BAP and provide the scientific justifications for the control strategy of the lake eutrophication.

  1. Trace element residues in water, sediments, and organs of Savacu (Nycticorax nycticorax from Sepetiba Bay, Rio de Janeiro, Brazil

    Directory of Open Access Journals (Sweden)

    Marco Aurélio P. Horta

    2010-04-01

    Full Text Available Heavy metal (Cr, Cd, Zn, Cu, Ni, Pb concentrations in water, sediment and organs of Savacu, Nycticorax nycticorax were analyzed. Samples of water and sediment were collected from seven stations along Sepetiba Bay, and experimental animals, also were collected in the study area. This bay receives effluents discharges from heavily industrialized and highly populated settlements. Samples of water, sediment and Savacu were processed and analyzed for heavy metals and the results showed that these concentrations in sediment were higher than in water. The exposure to metals either in the water or by the effect of bioaccumulation in the food chain is reflected in the results obtained with animals’ test.

  2. Time series monitoring of water quality and microalgal diversity in a tropical bay under intense anthropogenic interference (SW coast of the Bay of Bengal, India)

    Energy Technology Data Exchange (ETDEWEB)

    Shaik, Aziz ur Rahman [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India); Biswas, Haimanti, E-mail: haimanti.biswas@nio.org [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India); Reddy, N.P.C.; Srinivasa Rao, V. [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India); Bharathi, M.D. [Present address: ICMAM Project Directorate, 2nd Floor, NIOT Campus, Velacherry-Tambaram Main Road, Pallikkaranai, Chennai 600100 (India); Subbaiah, Ch.V. [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India)

    2015-11-15

    In recent decades, material fluxes to coastal waters from various land based anthropogenic activities have significantly been enhanced around the globe which can considerably impact the coastal water quality and ecosystem health. Hence, there is a critical need to understand the links between anthropogenic activities in watersheds and its health. Kakinada Bay is situated at the SW part of the Bay of Bengal, near to the second largest mangrove cover in India with several fertilizer industries along its bank and could be highly vulnerable to different types of pollutants. However, virtually, no data is available so far reporting its physicochemical status and microalgal diversity at this bay. In order to fill this gap, we conducted three time series observations at a fixed station during January, December and June 2012, at this bay measuring more than 15 physical, chemical and biological parameters in every 3 h over a period of 36 h in both surface (0 m) and subsurface (4.5 m) waters. Our results clearly depict a strong seasonality between three sampling months; however, any abnormal values of nutrients, biological oxygen demand or dissolved oxygen level was not observed. A Skeletonema costatum bloom was observed in December which was probably influenced by low saline, high turbid and high Si input through the river discharge. Otherwise, smaller diatoms like Thalassiosira decipiens, Thalassiothrix frauenfeldii, and Thalassionema nitzschioides dominated the bay. It is likely that the material loading can be high at the point sources due to intense anthropogenic activities, however, gets diluted with biological, chemical and physical processes in the offshore waters. - Highlights: • No signature of enormous nutrient loading was observed over the diel cycle • Dissolved oxygen and BOD concentrations did not show any exceptional trend • Diatoms dominated more than 90% of the total phytoplankton communities • A Skeletonema Costatum (a centric diatom) bloom was

  3. Production of a water quality map of Saginaw Bay by computer processing of LANDSAT-2 data

    Science.gov (United States)

    Mckeon, J. B.; Rogers, R. H.; Smith, V. E.

    1977-01-01

    Surface truth and LANDSAT measurements collected July 31, 1975, for Saginaw Bay were used to demonstrate a technique for producing a color coded water quality map. On this map, color was used as a code to quantify five discrete ranges in the following water quality parameters: (1) temperature, (2) Secchi depth, (3) chloride, (4) conductivity, (5) total Kjeldahl nitrogen, (6) total phosphorous, (7)chlorophyll a, (8) total solids and (9) suspended solids. The LANDSAT and water quality relationship was established through the use of a set of linear regression equations where the water quality parameters are the dependent variables and LANDSAT measurements are the independent variables. Although the procedure is scene and surface truth dependent, it provides both a basis for extrapolating water quality parameters from point samples to unsampled areas and a synoptic view of water mass boundaries over the 3000 sq. km bay area made from one day's ship data that is superior, in many ways, to the traditional machine contoured maps made from three day's ship data.

  4. Escherichia Coli and Biophysicochemical Relationships of Seawater and Water Pollution Index in the Jakarta Bay

    Directory of Open Access Journals (Sweden)

    Endan Suwandana

    2011-01-01

    Full Text Available Problem statement: Relationships between Escherichia coli (E. coli and biophysicochemical properties of seawater at different seasons and water pollution index were investigated in the Jakarta Bay, Indonesia. Approach: Water quality data taken at different seasons (Early Rainy Season (ERS in November 2007 and Late Dry Season (LDS in August 2008 were analyzed. Additionally, to compare pollution level at different seasons, Nemerow-Sumitomo Water Pollution Index (WPI was used. Results: Significant correlation of E. coli occured with only few parameters in the ERS, but with more parameters in the LDS. This might be due to the rainfall intensity in the ERS that was potential to dilute seawater and reduce concentration of some parameters, especially along the offshore stations. However, at the same time, the freshwater coming from land had capacity to force out the polluted water in 13 river systems flowing into the bay; hence it could generate more pollution along the onshore stations. Seawater pollution level slightly increased in the ERS in respect to the addition of polluted water from rivers. In this season, none station was clean, 20 stations were slightly polluted, six stations were moderately polluted and six stations were highly polluted. Meanwhile in the LDS, the number of stations following the above WPI criteria were 9, 16, 3 and 4, respectively, indicating less pollution level. Conclusion/Recommendations: The overall results showed that E. coli exhibited significant correlations with more water parameters in the LDS and the WPI showed a little increase in the ERS.

  5. California State Waters Map Series: Drakes Bay and vicinity, California

    Science.gov (United States)

    Watt, Janet T.; Dartnell, Peter; Golden, Nadine E.; Greene, H. Gary; Erdey, Mercedes D.; Cochrane, Guy R.; Johnson, Samuel Y.; Hartwell, Stephen R.; Kvitek, Rikk G.; Manson, Michael W.; Endris, Charles A.; Dieter, Bryan E.; Sliter, Ray W.; Krigsman, Lisa M.; Lowe, Erik N.; Chinn, John L.; Watt, Janet T.; Cochran, Susan A.

    2015-01-01

    In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology.

  6. Summary of oceanographic and water-quality measurements in Barnegat Bay, New Jersey, 2014–15

    Science.gov (United States)

    Suttles, Steven E.; Ganju, Neil K.; Montgomery, Ellyn T.; Dickhudt, Patrick J.; Borden, Jonathan; Brosnahan, Sandra M.; Martini, Marinna A.

    2016-09-26

    Scientists and technical support staff from the U.S. Geological Survey measured suspended-sediment concentrations, currents, pressure, and water temperature in two tidal creeks, Reedy Creek and Dinner Creek, in Barnegat Bay, New Jersey, from August 11, 2014, to July 10, 2015 as part of the Estuarine Physical Response to Storms project (GS2–2D). The oceanographic and water-quality data quantify suspended-sediment transport in Reedy Creek and Dinner Creek, which are part of a tidal marsh wetland complex in the Edwin B. Forsythe National Wildlife Refuge. All deployed instruments were removed between January 7, 2015, and April 14, 2015, to avoid damage by ice.

  7. Ground water hydrochemical characteristics:seawater intruded area in eastern and southern coast of Laizhou Bay

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Eastern and southern coastal zones of Laizhou Bay are the mostrepresentative seawater intruded areas in the world, with two intrusion sources of contemporary seawater and paleobrine. In order to reveal the complicated hydrochemical changing process and the mechanism of fresh groundwater being polluted by saltwater, we conducted long-term observation and hydroehemical analysis at four observing sections of typical salt-fresh water transitional zone. The study indicates that seawater and brine intrusion processes have different hydrochemical features, and that ion exchange and adsorption actions between water and aquifer produce great influence on the intrusion.

  8. The numbers of ringed seals (Phoca hispida in Baffin Bay and associated waters

    Directory of Open Access Journals (Sweden)

    Michael C S Kingsley

    1998-06-01

    Full Text Available The size of the population of ringed seals (Phoca hispida inhabiting Baffin Bay and associated waters was estimated by two methods. An approximate model of the energetics of the polar bear (Ursus maritimus estimated an energetic need of about 16,000 MJ/bear per year. Modelled estimates of the energetic yield of a ringed seal population showed that a stable standing population of 140-170 ringed seals per bear would be needed to provide that much energy, assuming that all mortalities were due to polar bear predation. This result was sensitive to assumptions about the Field Metabolic Rate (FMR of the bears and the energetic yield of individual ringed seals, but less sensitive to assumptions about relative incidence of predation on different age classes of seal or the age structure of the polar bear population. Estimated sizes of polar bear populations in Baffin Bay and associated waters (total about 4,025, and of the standing population needed to support an estimated hunter kill of 100,000 yielded a population estimate of, very roughly, 1.2 million ringed seals. Estimates of ice areas and of the density of hauled out seals from aerial surveys were used to generate another approximate figure for the ringed seal population, which was about the same. The density of seals in the pack-ice area of Baffin Bay, which is imperfectly known, has a large influence on the latter estimate.

  9. Discharge of Oilfield-Produced Water in Nueces Bay, Texas: A Case Study

    Science.gov (United States)

    D'Unger, Claude; Chapman, Duane; Carr, R. Scott

    1996-01-01

    During oil and gas production, water is often extracted from geological formations along with the hydrocarbons. These “produced waters” have been discharged to Nueces Bay since the turn of the century. These effluents were found to be highly toxic, and sediments in the vicinity of the discharges were also toxic. We developed a map of wells and produced-water discharge sites in the vicinity of Nueces Bay and identified numerous unplugged wells suitable for conversion to produced water disposal wells. An economic analysis of conversion to subterranean injection of produced water indicates that most of the wells currently in production could pay out the cost of conversion to injection in one to three years. The use of one injection well for two or more water-producing wells could yield greater savings. Wells that could not support the cost of injection are small producers, and their loss would not constitute a major loss of jobs or dollars to the area. This study could serve as a useful model for evaluating the economic feasibility of conversion to injection in other areas of Texas and Louisiana.

  10. Major element concentrations in Mangrove Pore Water, Sepetiba Bay, Brazil

    Directory of Open Access Journals (Sweden)

    Christian J. Sanders

    2012-03-01

    Full Text Available Concentrations of cations and anions of major elements (Na+, Ca2+, Mg2+, K+, Cl-, SO4 2- were analyzed in the pore water of a mangrove habitat. Site specific major element concentrations were identified along a four piezometric well transect, which were placed in distinct geobotanic facies. Evapotranspiration was evident in the apicum station, given the high salinity and major element concentrations. The station landward of an apicum was where major element/Cl- ratios standard deviations are greatest, suggesting intense in situ diagenesis. Molar ratios in the most continental station (4 are significantly lower than the nearby freshwater source, indicating a strong influence of sea water flux into the outer reaches of the mangrove ecosystem and encroaching on the Atlantic rain forest. Indeed, the SO4 2-/Cl- and Ca2+/Cl- ratios suggest limited SO4 2- reduction and relatively high Ca2+/Cl- ratios indicate a region of recent saltwater contact.As concentrações dos elementos maiores (Na+, Ca2+, Mg2+, K+, Cl-, SO4(2- foram analisadas na água intersticial de poços piezométricos localizados em diferentes fácies geobotânicas ao longo de um transecto num ecossistema de manguezal na Baía de Sepetiba - Rio de Janeiro. Maiores salinidades e concentrações dos íons maiores são evidencias de evapotranspiração no fácies apicum. Ainda no apicum foram observados os maiores desvios padrão da razão elemento/Cl− durante o período do estudo, indicando intensa diagênese in situ. Razões molares no piezômetro, localizado na borda do manguezal foram consideravelmente menores do que a fonte de água doce, indicando forte influência do fluxo de água marinha. Os resultados das razões molares, SO4(2-/Cl− e Ca2+/Cl− na borda do manguezal adjacente ao continente sugerem limitada redução de SO4(2- enquanto os valores relativamente altos na razão Ca2+/Cl− indicam contacto recente com água marinha.

  11. Respiration rates in subsurface waters of the northern Indian Ocean: Evidence for low decomposition rates of organic matter within the water column in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Shailaja, M.S.; DileepKumar, M.; Sengupta, R.

    Depth profiles of activity of the respirtory Electron Transport System (ETS) have been generated at several locations in the northern Indian Ocean. The results reveal much lower ETS activities in subsurface waters of the Bay of Bengal than those...

  12. Long-term isolation and local adaptation in Palau's Nikko Bay help corals thrive in acidic waters

    Science.gov (United States)

    Golbuu, Yimnang; Gouezo, Marine; Kurihara, Haruko; Rehm, Lincoln; Wolanski, Eric

    2016-09-01

    The reefs in Palau's Nikko Bay live in seawater with low pH that is similar to conditions predicted for 2100 because of ocean acidification. Nevertheless, the reefs at Nikko Bay have high coral cover and high diversity. We hypothesize that the low-pH environment in Nikko Bay is caused by low flushing rates, which causes long-term isolation and local adaptation. To test this hypothesis, we modeled the water circulation in and around Nikko Bay. Model results show that average residence time is 71 d, which is ten times the residence time on fore-reef habitats. The long residence time restricts the exchange of coral larvae in the bay with adjacent reefs, allowing persistent selection for tolerant traits and local adaptation. The corals in Nikko Bay are also more susceptible to local pollution because the waters are poorly flushed. Therefore, local management must focus on minimizing human impacts such as dredging, overfishing and pollution in the bay, which would compromise the condition of the corals that have already adapted to low-pH conditions.

  13. Vertical variation of oxygen isotope in Bay of Bengal and its relationships with water masses

    Science.gov (United States)

    Sengupta, S.; Parekh, Anant; Chakraborty, S.; Ravi Kumar, K.; Bose, T.

    2013-12-01

    We present here, for the first time, comprehensive depth specific (near surface to 1800 m) oxygen isotope (δ18O) data set of 175 water samples collected from 22 different locations in the Bay of Bengal (BoB) during July-August 2009 and December-January 2012-2013. The study is aimed to constrain the water mass parameters using oxygen isotope and salinity. Four water masses are identified on the basis of temperature-salinity relationship: (a) Bay of Bengal Water (BoBW; 0-50 m), (b) Mixed Zone (MZ; 60-120 m), (c) Indonesian Throughflow (ITF; 200-500 m), and (d) Indian Ocean Deep Water (IDW; 600-1800 m). Our study shows: (1) δ18O-salinity correlation (slope = 0.15 ± 0.01; intercept = -4.58 ± 0.24; r2 = 0.89; n = 54) for the BoBW is found to be consistent with surface BoB water reported earlier, (2) relatively lower correlation (r2 = 0.24; n = 47) in underlying mixed zone suggesting mixing of various water masses, (3) significant linear correlation between δ18O and salinity in IDW (r2 = 0.70) indicating depleted less saline water from southern hemisphere spread up to 18°N, and (4) vertical profiles at various sampling locations showing a continuous enrichment of δ18O (0.6-0.8‰) within top 60-100 m irrespective of their proximity to coastline. In conjunction with a sharp decrease in Δ14C data below the same depth zone (60-100 m) as reported earlier, we suggest the δ18O value reaches to its acme at a zone of mixing between younger BoBW and relatively older ITF. This preliminary study indicates oxygen isotope and salinity together can be used to identify different water masses in the BoB.

  14. Numerical study on the influences of Nanliu River runoff and tides on water age in Lianzhou Bay

    Science.gov (United States)

    Yu, Jing; Zhang, Xueqing; Liu, Jinliang; Liu, Rui; Wang, Xing

    2016-09-01

    The concept of water age is applied to calculate the timescales of the transport processes of freshwater in Lianzhou Bay, using a model based on ECOMSED. In this study, water age is defined as the time that has elapsed since the water parcel enters the Nanliu River. The results show that the mean age at a specified position and the runoff of the Nanliu River are well correlated and can be approximately expressed by a natural logarithmic function. During the neap tide, it takes 70, 60 and 40 days in the dry, normal and rainy seasons for water to travel from the mouth of the Nanliu River to the northeast of Lianzhou Bay, respectively, which is not beneficial to water exchange in the bay. Tides significantly influence the model results; it takes five less days for the tracer to be transported from the mouth of the Nanliu River to the north of Guantouling during the spring tide than during the neap tide.

  15. Cold-Water Coral Habitats in Submarine Canyons of the Bay of Biscay

    Directory of Open Access Journals (Sweden)

    Inge M. J. van den Beld

    2017-05-01

    Full Text Available The topographical and hydrological complexity of submarine canyons, coupled with high substratum heterogeneity, make them ideal environments for cold-water coral (CWC habitats. These habitats, including reefs, are thought to provide important functions for many organisms. The canyons incising the continental slope of the Bay of Biscay have distinct morphological differences from the north to the south. CWCs have been reported from this basin in the late nineteenth century; however, little is known about their present-day distribution, diversity and environmental drivers in the canyons. In this study, the characteristics and distribution of CWC habitats in the submarine canyons of the Bay of Biscay are investigated. Twenty-four canyons and three locations between adjacent canyons were sampled using a Remotely Operated Vehicle (ROV or a towed camera system. Acquired images were annotated for habitat type (using the CoralFISH classification system, substrate cover and coral identification. Furthermore, the influence of hydrological factors and geomorphology on the CWC distribution was investigated. Eleven coral habitats, formed by 62 morphotypes of scleractinians, gorgonians, antipatharians and seapens, inhabiting hard and/or soft substrate, were observed. The distribution patterns were heterogenous at regional and local scales; the south Bay of Biscay and the southeastern flank favored soft substrate habitats. Biogenic and hard substrate habitats supported higher coral diversities than soft substrate habitats and had similar species compositions. A higher coral species turnover characterized soft substrate habitats. Substrate type was the most important driver of the patterns in both distribution and composition. Observations of coral reefs on steeper areas in the canyons and coral rubble on flatter areas on the interfluve/upper slope support the hypothesis that canyons serve as refuges, being less accessible to trawling, although natural causes

  16. Air-sea CO2 flux pattern along the southern Bay of Bengal waters

    Science.gov (United States)

    Shanthi, R.; Poornima, D.; Naveen, M.; Thangaradjou, T.; Choudhury, S. B.; Rao, K. H.; Dadhwal, V. K.

    2016-12-01

    Physico-chemical observations made from January 2013 to March 2015 in coastal waters of the southwest Bay of Bengal show pronounced seasonal variation in physico-chemical parameters including total alkalinity (TA: 1927.390-4088.642 μmol kg-1), chlorophyll (0.13-19.41 μg l-1) and also calculated dissolved inorganic carbon (DIC: 1574.219-3790.954 μmol kg-1), partial pressure of carbon dioxide (pCO2: 155.520-1488.607 μatm) and air-sea CO2 flux (FCO2: -4.808 to 11.255 mmol Cm-2 d-1). Most of the physical parameters are at their maximum during summer due to the increased solar radiation at cloud free conditions, less or no riverine inputs, and lack of vertical mixing of water column which leads to the lowest nutrients concentration, dissolved oxygen (DO), biological production, pCO2 and negative flux of CO2 to the atmosphere. Chlorophyll and DO concentrations enhanced due to increased nutrients during premonsoon and monsoon season due to the vertical mixing of water column driven by the strong winds and external inputs at respective seasons. The constant positive loading of nutrients, TA, DIC, chlorophyll, pCO2 and FCO2 against atmospheric temperature (AT), lux, sea surface temperature (SST), pH and salinity observed in principal component analysis (PCA) suggested that physical and biological parameters play vital role in the seasonal distribution of pCO2 along the southwest Bay of Bengal. The annual variability of CO2 flux clearly depicted that the southwest Bay of Bengal switch from sink (2013) to source status in the recent years (2014 and 2015) and it act as significant source of CO2 to the atmosphere with a mean flux of 0.204 ± 1.449 mmol Cm-2 d-1.

  17. Abundance and physiology of dominant soft corals linked to water quality in Jakarta Bay, Indonesia

    Directory of Open Access Journals (Sweden)

    Gunilla Baum

    2016-11-01

    Full Text Available Declining water quality is one of the main reasons of coral reef degradation in the Thousand Islands off the megacity Jakarta, Indonesia. Shifts in benthic community composition to higher soft coral abundances have been reported for many degraded reefs throughout the Indo-Pacific. However, it is not clear to what extent soft coral abundance and physiology are influenced by water quality. In this study, live benthic cover and water quality (i.e. dissolved inorganic nutrients (DIN, turbidity (NTU, and sedimentation were assessed at three sites (< 20 km north of Jakarta in Jakarta Bay (JB and five sites along the outer Thousand Islands (20–60 km north of Jakarta. This was supplemented by measurements of photosynthetic yield and, for the first time, respiratory electron transport system (ETS activity of two dominant soft coral genera, Sarcophyton spp. and Nephthea spp. Findings revealed highly eutrophic water conditions in JB compared to the outer Thousand Islands, with 44% higher DIN load (7.65 μM/L, 67% higher NTU (1.49 NTU and 47% higher sedimentation rate (30.4 g m−2 d−1. Soft corals were the dominant type of coral cover within the bay (2.4% hard and 12.8% soft coral cover compared to the outer Thousand Islands (28.3% hard and 6.9% soft coral cover. Soft coral abundances, photosynthetic yield, and ETS activity were highly correlated with key water quality parameters, particularly DIN and sedimentation rates. The findings suggest water quality controls the relative abundance and physiology of dominant soft corals in JB and may thus contribute to phase shifts from hard to soft coral dominance, highlighting the need to better manage water quality in order to prevent or reverse phase shifts.

  18. Numerical analysis on water exchange and its response to the coastal engineering in the Yueqing Bay in China

    Institute of Scientific and Technical Information of China (English)

    LI Jia; YAO Yanming; LI Xiaoyan; ZHANG Hongwei

    2008-01-01

    On the basis of a numerical model of tidal current using Delft3D, the distribution of the semi - exchange time of water was simula- ted in the Yueqing Bay here. The result showed that the semi - exchange time was about more than 6 d in the bay end, and about 1~2 d in the bay mouth. Besides, based on the calculation of the semi - exchange time before and after the Xuanmen Dam pro- ject, a comparison between them was further carried out. And the same work was also done with the recent reclamation projects in the Yueqing Bay as well. The results showed that the change in semi - exchange time caused by the Xuanmen Dam project was a- bout 6 d increase near the dam and 4.5 d increase at the bay end. And it was about 5 d increase at the bay end and 1 d increase at the mouth of the bay caused by the recent reclamation projects.

  19. Evaluation of ERTS MSS digital data for monitoring water in the lower Chesapeake Bay area

    Science.gov (United States)

    Bowker, D. E.; Witte, W. G.

    1975-01-01

    Water samples collected during the ERTS overpasses of the lower Chesapeake Bay area have been analyzed for chlorophyll, particles, and sediment. Five ERTS images were sufficiently cloud free that a correlation analysis of radiance values from the MSS bands with the water parameters could be performed. A low correlation was established for chlorophyll, except during algal blooms, when band 6 was responsive. There was a fair to good correlation with particles for combinations of band 5, particularly bands (5 minus 6). Sediment correlations were excellent for band 5 or combinations of band 5 with bands 4 and 6. It was evident that such factors as the atmosphere, tide, and different water masses were tending to confuse the data.

  20. Geochemistry of Clayey Aquitard Pore Water as Archive of Paleo-Environment, Western Bohai Bay

    Institute of Scientific and Technical Information of China (English)

    Jing Li; Xing Liang; Menggui Jin; Guoqiang Xiao; Jishan He; Yandong Pei

    2015-01-01

    The record of paleo-environment in clayey aquitard pore water is much more effective relative to aquifer groundwater owing to the low permeability of clayey aquitard. Oxygen-18 (18O), deuterium (D), and chemical patterns were determined in pore water samples extracted from two 500 m depth boreholes, G1 and G2, in western Bohai Bay, China. Shallow pore water samples (depth<102 m) are saline water, with the TDS (total dissolved solids) of 3.69–30.75 g/L, and deeper ones (depth=102–500 m) are fresh water, with the TDS<1 g/L. Content of major ions (i.e., Cl-, Na+, K+, Mg2+, SO42-, Ca2+) is high in marine sediment pore water samples and gradually decrease towards to terre-strial sediment pore water, together with the Cl/Br and Sr/Ba ratios changing significantly in different sedimentary facies along the study profile, indicating that pore water may be paleo-sedimentary water and not replaced by modern water.δ18O profile and positive correlation betweenδ18O and Cl-of shal-low saline pore water indicated diffusion as the main transport mechanism, and distinguished four transgressive layers since Late Quaternary (i.e., Holocene marine unit, two Late Pleistocene marine units and Middle Pleistocene marine unit), further supporting the finding that pore water retained the feature of paleo-sedimentary water. Climate was identified as the main influence on the isotopic signa-ture of aquitard pore water and four climate periods were determined byδ18O profile.

  1. Salinity maxima associated with some sub-surface water masses in the upper layers of the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Varadachari, V.V.R.; Murty, C.S.; Reddy, C.V.G.

    The distribution of some sub-surface water masses in the western bay of Bengal during the south-west monsoon period is presented. Based on the salinity maxima and sigma t values the existence of waters of Persian Gulf and Red Sea origin could...

  2. Parabolic stationing method application to intertidal shellfish (Sinonovacula constricta) and growing waters microbiological monitoring in Yueqing Bay, China.

    Science.gov (United States)

    Jin, Lei; Liu, Huan; Xu, Dan; Gu, Beiqiao

    2017-03-15

    This study reported microbiological monitoring by parabolic stationing method for S. constricta and their growing waters, and application for the first time in Yueqing Bay, China. The results indicated that numbers of Escherichia coli and aerobic colony count in S. constricta flesh showed an approximate 'parabola' distribution across the whole shellfish bed. Numbers of faecal coliform in seawater samples were significantly higher in the top of the bay, and lower in the lower half of the bay, whilst higher located in the edge of the bay than the center in contrast to three sampling sites on the same latitude. Numbers of total bacterial count were not significantly correlated with faecal coliform in seawater samples. Finally, the shellfish production areas were classified based on three batches of E. coli monitoring. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Challenges associated with modeling low-oxygen waters in Chesapeake Bay: a multiple model comparison

    Directory of Open Access Journals (Sweden)

    I. D. Irby

    2015-12-01

    Full Text Available As three-dimensional (3-D aquatic ecosystem models are becoming used more frequently for operational water quality forecasts and ecological management decisions, it is important to understand the relative strengths and limitations of existing 3-D models of varying spatial resolution and biogeochemical complexity. To this end, two-year simulations of the Chesapeake Bay from eight hydrodynamic-oxygen models have been statistically compared to each other and to historical monitoring data. Results show that although models have difficulty resolving the variables typically thought to be the main drivers of dissolved oxygen variability (stratification, nutrients, and chlorophyll, all eight models have significant skill in reproducing the mean and seasonal variability of dissolved oxygen. In addition, models with constant net respiration rates independent of nutrient supply and temperature reproduced observed dissolved oxygen concentrations about as well as much more complex, nutrient-dependent biogeochemical models. This finding has significant ramifications for short-term hypoxia forecasts in the Chesapeake Bay, which may be possible with very simple oxygen parameterizations, in contrast to the more complex full biogeochemical models required for scenario-based forecasting. However, models have difficulty simulating correct density and oxygen mixed layer depths, which are important ecologically in terms of habitat compression. Observations indicate a much stronger correlation between the depths of the top of the pycnocline and oxycline than between their maximum vertical gradients, highlighting the importance of the mixing depth in defining the region of aerobic habitat in the Chesapeake Bay when low-oxygen bottom waters are present. Improvement in hypoxia simulations will thus depend more on the ability of models to reproduce the correct mean and variability of the depth of the physically driven surface mixed layer than the precise magnitude of the

  4. Challenges associated with modeling low-oxygen waters in Chesapeake Bay: a multiple model comparison

    Science.gov (United States)

    Irby, Isaac D.; Friedrichs, Marjorie A. M.; Friedrichs, Carl T.; Bever, Aaron J.; Hood, Raleigh R.; Lanerolle, Lyon W. J.; Li, Ming; Linker, Lewis; Scully, Malcolm E.; Sellner, Kevin; Shen, Jian; Testa, Jeremy; Wang, Hao; Wang, Ping; Xia, Meng

    2016-04-01

    As three-dimensional (3-D) aquatic ecosystem models are used more frequently for operational water quality forecasts and ecological management decisions, it is important to understand the relative strengths and limitations of existing 3-D models of varying spatial resolution and biogeochemical complexity. To this end, 2-year simulations of the Chesapeake Bay from eight hydrodynamic-oxygen models have been statistically compared to each other and to historical monitoring data. Results show that although models have difficulty resolving the variables typically thought to be the main drivers of dissolved oxygen variability (stratification, nutrients, and chlorophyll), all eight models have significant skill in reproducing the mean and seasonal variability of dissolved oxygen. In addition, models with constant net respiration rates independent of nutrient supply and temperature reproduced observed dissolved oxygen concentrations about as well as much more complex, nutrient-dependent biogeochemical models. This finding has significant ramifications for short-term hypoxia forecasts in the Chesapeake Bay, which may be possible with very simple oxygen parameterizations, in contrast to the more complex full biogeochemical models required for scenario-based forecasting. However, models have difficulty simulating correct density and oxygen mixed layer depths, which are important ecologically in terms of habitat compression. Observations indicate a much stronger correlation between the depths of the top of the pycnocline and oxycline than between their maximum vertical gradients, highlighting the importance of the mixing depth in defining the region of aerobic habitat in the Chesapeake Bay when low-oxygen bottom waters are present. Improvement in hypoxia simulations will thus depend more on the ability of models to reproduce the correct mean and variability of the depth of the physically driven surface mixed layer than the precise magnitude of the vertical density gradient.

  5. Modification of the vertically generalized production model for the turbid waters of Ariake Bay, southwestern Japan

    Science.gov (United States)

    Tripathy, S. C.; Ishizaka, J.; Siswanto, E.; Shibata, T.; Mino, Y.

    2012-01-01

    The vertically generalized production model (VGPM), which was designed for open ocean waters ( Behrenfeld and Falkowski, 1997a; henceforth BF), was evaluated using in situ measurements of primary productivity (PP) in the characteristically turbid coastal waters of Ariake Bay, southwestern Japan, to develop a regionally modified version of the model. The euphotic depth ( Z eu)-integrated PP (IPP) calculated from the VGPM using in situ chlorophyll a (Chl a) and sea surface temperature (SST) was significantly overestimated (by factors of 2-3), but 52% of the observed variability was explained. The weak correlation could have partially resulted from overestimations by the sub-models embedded in the original VGPM model for estimation of Z eu ( Morel and Berthon, 1989; henceforth MB) and the optimal Chl a-normalized PP ( poptB). The sub-model estimates of poptB and Z eu with in situpoptB and Z eu showed significant improvement, accounting for 84% of the variability and causing less overestimation. Z eu was the most important parameter influencing the modeled IPP variation in Ariake Bay. Previous research suggested that the Z eu model, which was based on surface Chl a, overestimated in situ Z eu by a factor of 2-3, resulting in weak correlation between the modeled and in situ IPP. The Z eu sub-model was not accurate in the present study area because it was basically developed for clear (case 1) waters. A better estimation of Z eu could be obtained from the in situ remote sensing reflectance ( R rs) using a quasi-analytical algorithm (QAA) in this turbid water ecosystem. Among the parameters of PP models, poptB is conventionally considered the most important. However, in this study poptB was of secondary importance because the contribution of poptB to the variation in modeled IPP was less than the contribution of Z eu. The modeled and in situpoptB were weakly correlated with 50% of the data points that overestimated the in situ values. The estimation of Chl a was improved

  6. A New Small Drifter for Shallow Water Basins: Application to the Study of Surface Currents in the Muggia Bay (Italy

    Directory of Open Access Journals (Sweden)

    Carmelo Nasello

    2016-01-01

    Full Text Available A new small drifter prototype for measuring current immediately below the free surface in a water basin is proposed in this paper. The drifter dimensions make it useful for shallow water applications. The drifter transmits its GPS location via GSM phone network. The drifter was used to study the trajectory of the surface current in the Muggia bay, the latter containing the industrial harbor of the city of Trieste (Italy. The analysis has been carried out under a wide variety of wind conditions. As regards the behavior of the drifter, the analysis has shown that it is well suited to detect the water current since its motion is marginally affected by the wind. The study has allowed detecting the main features of the surface circulation within the Muggia bay under different meteorological conditions. Also, the study has shown that the trajectory of the surface current within the bay is weakly affected by the Coriolis force.

  7. Fluorescent dissolved organic matter in the continental shelf waters of western Bay of Bengal

    Indian Academy of Sciences (India)

    N V H K Chari; P Sudarsana Rao; Nittala S Sarma

    2013-10-01

    Fluorescent dissolved organic matter (FDOM) of southwestern Bay of Bengal surface water during southwest monsoon consisted five fluorophores, three humic-like and two protein-like. The humification index (HIX) and humic fluorophores, viz., visible (C), marine (M) and UV (A) humic-likes indicated, better than biogeochemical constituents analyzed, that the northern-half region of the study area which is closer to the head bay (less salinity) is distinctly more terrestrially influenced. Similarly, the southernhalf region (less dissolved oxygen) is indicated as more in situ influenced. This region is enriched with tyrosine protein-like fluorophore (B), an indicator of bacterial metabolism in some of its samples due to upwelled water. Although chlorophyll is less in this (southern) region, the fluorescence based biological index (BIX) which is an index of recent phytoplankton production is about the same in the two regions, and the lower chlorophyll of southern region is attributed to greater grazing pressure. Fluorescence properties, e.g., BIX are more informative about phytoplankton production than chlorophyll .

  8. Integrating satellite imagery and geostatistics of point samples for monitoring spatio-temporal changes of total suspended solids in bay waters: application to Tien Yen Bay (Northern Vietnam)

    Institute of Scientific and Technical Information of China (English)

    Nguyen Thi Thu HA; Katsuaki KOIKE

    2011-01-01

    High concentrations of total suspended solids (TSS)in coastal and bay areas strongly affect water quality and aquatic ecosystems.Frequent monitoring of spatiotemporal changes of TSS distribution in such areas is indispensable for understanding sediment fluxes and water cycles,and to preserve ecosystem health.This study aimed to identify appropriate and sufficient tools for assessing changes in TSS distribution in Tien Yen Bay in Northem Vietnam,a typical closed bay,which was selected as the study area because of its rich biodiversity.Initially,a physical based model using the reflectance at the sea surface was developed for estimating TSS concentrations from satellite image data,and a model with an exponential function was identified as suitable for the estimation.This model was fitted appropriately to provide a relationship between reflectance from the MODIS/Terra band 1(visible red)after the atmospheric correction and the in situ TSS concentrations at 40 points.Ordinary kriging was then shown to be effective in improving the spatial resolution of the MODIS/Terra image-based estimation of the TSS concentration at a 250 m interval,because it could detect TSS variation in detail,in particular in the local estuaries.TSS distributions derived from 12 MODIS/Terra images from November 2009 to October 2010 clarified seasonal changes in TSS during one year.TSS concentrations were high during summer and lower during fall and winter.Such trends were conformable with the hydrodynamics in Tien Yen Bay.Consequently,the proposed method was more effective for TSS estimation than traditional methods using satellite image data only.

  9. Cold seeps in Monterey Bay, California: Geochemistry of pore waters and relationship to benthic foraminiferal calcite

    Energy Technology Data Exchange (ETDEWEB)

    Gieskes, Joris, E-mail: jgieskes@ucsd.edu [Scripps Institution of Oceanography, IOD-0208, 9500 Gilman Drive, La Jolla, CA 92093-0208 (United States); Rathburn, Anthony E. [Scripps Institution of Oceanography, IOD-0208, 9500 Gilman Drive, La Jolla, CA 92093-0208 (United States)] [Indiana State University, Department of Earth and Environmental Systems, Terre Haute, IN 47809 (United States); Martin, Jonathan B. [University of Florida, Department of Geological Sciences, Gainesville, FL 32611-2120 (United States); Perez, M. Elena [Indiana State University, Department of Earth and Environmental Systems, Terre Haute, IN 47809 (United States)] [The Natural History Museum, Department of Palaeontology, Cromwell Road, London SW7 5BD (United Kingdom); Mahn, Chris [Scripps Institution of Oceanography, IOD-0208, 9500 Gilman Drive, La Jolla, CA 92093-0208 (United States); Bernhard, Joan M. [Woods Hole Oceanographic Institution, Geology and Geophysics Department, MS52, Woods Hole, MA 02543 (United States); Day, Shelley [University of Florida, Department of Geological Sciences, Gainesville, FL 32611-2120 (United States)

    2011-05-15

    Highlights: > We describe the geochemistry of pore waters in the Clam Flats area of Monterey Bay. > The geochemical data are compared with the {delta}{sup 13}C chemistry of benthic foraminifera. > Living foraminifera indicate little effects of pore water low {delta}{sup 13}C (DIC) in the clam bed. > This phenomenon and its implications are discussed in detail. > Implications with regards to paleo-methane seepage are discussed. - Abstract: An extensive geochemical and biogeochemical examination of CH{sub 4} seeps in the Clam Flats area of Monterey Bay provides insight into the character of relationships between seep geochemistry and benthic foraminiferal geochemistry. The area is characterized by sulfide-rich fluids. Sulfide increases are associated with large increases in alkalinity, as well as small decreases in dissolved Ca and Mg. In addition, only small increases in NH{sub 4} are observed, but values of {delta}{sup 13}C of dissolved inorganic C are as low as -60 per mille at shallow depths (<3 cm). These observations indicate that all these processes are related to the bacterial oxidation of CH{sub 4}, which is transported upward by slow seepage of pore fluids. The geochemistry of the pore fluids should be relevant to the geochemistry of the carbonate tests of living and dead foraminifera. However, a profound disequilibrium of approximately an order of magnitude occurs between the {delta}{sup 13}C values of stained (cytoplasm-containing) foraminiferal carbonate and the C isotope values of ambient pore water dissolved inorganic C. Reasons are unclear for this isotopic disequilibrium, but have important implications for interpretations of foraminiferal carbonate as a paleoenvironmental proxy. Much fine scale work is needed to fully understand the relationships between the biogeochemistry of benthic foraminifera and the geochemistry of the pore waters where they live.

  10. [Effects of sediment dredging on benthos community structure and water quality in Zhushan Bay].

    Science.gov (United States)

    Liu, Guo-Feng; Zhang, Zhi-Yong; Liu, Hai-Qin; Zhong, Ji-Cheng; Yan, Shao-Hua; Fan, Cheng-Xin

    2010-11-01

    We surveyed the changes of macro-benthos community composition and nutrients concentration in water in Zhushan Bay after it had been dredged 6 months, which aimed to remove the polluted surface sediments. The results showed that the main benthos in the dredged and un-dredged sediments were Limodrilus hoffmeisteri, Pelopia and Bellamya aeruginosa; compared to the un-dredged sediments, the bio-diversity of dredged areas became lower. However, its biomass became higher than that in un-dredged areas. Concentration range changes of TN and TP in overlying water was 1.64-4.45 mg/L and 0.133-0.258 mg/L, respectively. The post-dredged sediments were still in a higher state of nutrients for the higher concentration nutrients in overlying water, macro-benthos were the species that lived in a serious polluted water environment. Using Shannon-Weaver, Simpson, and Goodnight benthic index to evaluate the results show that the dredged area is in the moderately polluted level, but un-dredged area is in the middle-heavily polluted level. According to the benthos fauna surveys and water quality monitoring results, the effective of sediment dredging could play its role only the strict control on the external pollution resources have been made and reduces the effects of polluted water on the sediments.

  11. Socioeconomic Response to Water Quality: a First Experience in Science and Policy Integration for the Izmit Bay Coastal System

    Directory of Open Access Journals (Sweden)

    Leyla Gamze Tolun

    2012-09-01

    Full Text Available Deterioration of the Izmit Bay ecosystem, mainly caused by heavy industrialization and urbanization, has significantly impaired its beneficial use and resulted in the surrounding coastal zone losing its attractiveness for the inhabitants. An integrated coastal zone management approach has become an important requirement of future development plans to protect this fragile bay ecosystem. One of the main indicators of deterioration of the Izmit Bay coastal system is the decreasing water quality resulting from increased nutrient loads from the surrounding land.The consensus during the initial stakeholder meeting confirmed the widespread awareness of this phenomenon and "improvement of water quality in Izmit Bay" was determined as the main policy issue at stake. Public perception of and satisfaction with water quality were measured by a willingness to pay (WTP survey. The WTP for improved water quality was analyzed using the contingent valuation method. According to the questionnaire survey, 55% of the participants are willing to pay to increase the water quality. Impact of water quality on real-estate values was evaluated by hedonic pricing method, which is suitable for estimating direct and indirect use values of water resources. These results were used in a simulation model to assess coupled ecosystem, social, and economic system functioning of the Izmit Bay in response to various scenarios, and thus, to permit the necessary actions to be taken proactively. Two scenario simulations, for which domestic and runoff nitrogen loads are reduced independently, showed that hypothetical domestic wastewater treatment resulted in an improvement in simulated water transparency. The results suggest that domestic wastewater treatment should be a first priority for local administrations.

  12. California State Waters Map Series: offshore of Half Moon Bay, California

    Science.gov (United States)

    Cochrane, Guy R.; Dartnell, Peter; Greene, H. Gary; Johnson, Samuel Y.; Golden, Nadine E.; Hartwell, Stephen R.; Dieter, Bryan E.; Manson, Michael W.; Sliter, Ray W.; Ross, Stephanie L.; Watt, Janet T.; Endris, Charles A.; Kvitek, Rikk G.; Phillips, Eleyne L.; Erdey, Mercedes D.; Chin, John L.; Bretz, Carrie K.

    2014-01-01

    In 2007, the California Ocean Protection Council initiated the California Seafloor Mapping Program (CSMP), designed to create a comprehensive seafloor map of high-resolution bathymetry, marine benthic habitats, and geology within the 3-nautical-mile limit of California’s State Waters. The CSMP approach is to create highly detailed seafloor maps through collection, integration, interpretation, and visualization of swath sonar data, acoustic backscatter, seafloor video, seafloor photography, high-resolution seismic-reflection profiles, and bottom-sediment sampling data. The map products display seafloor morphology and character, identify potential marine benthic habitats, and illustrate both the surficial seafloor geology and shallow (to about 100 m) subsurface geology. The Offshore of Half Moon Bay map area is located in northern California, on the Pacific coast of the San Francisco Peninsula about 40 kilometers south of the Golden Gate. The city of Half Moon Bay, which is situated on the east side of the Half Moon Bay embayment, is the nearest significant onshore cultural center in the map area, with a population of about 11,000. The Pillar Point Harbor at the north edge of Half Moon Bay offers a protected landing for boats and provides other marine infrastructure. The map area lies offshore of the Santa Cruz Mountains, part of the northwest-trending Coast Ranges that run roughly parallel to the San Andreas Fault Zone. The Santa Cruz Mountains lie between the San Andreas Fault Zone and the San Gregorio Fault system. The flat coastal area, which is the most recent of numerous marine terraces, was formed by wave erosion about 105 thousand years ago. The higher elevation of this same terrace west of the Half Moon Bay Airport is caused by uplift on the Seal Cove Fault, a splay of the San Gregorio Fault Zone. Although originally incised into the rising terrain horizontally, the ancient terrace surface has been gently folded into a northwest-plunging syncline by

  13. Water column particulate matter: A key contributor to phosphorus regeneration in a coastal eutrophic environment, the Chesapeake Bay: Particulate phosphorus in the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jiying [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Reardon, Patrick [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland Washington USA; Now at NMR Facility, Oregon State University, Corvallis Oregon USA; McKinley, James P. [Geochemistry Group, Pacific Northwest National Laboratory, Richland Washington USA; Joshi, Sunendra R. [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Bai, Yuge [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Bear, Kristi [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA; Jaisi, Deb P. [Department of Plant and Soil Sciences, University of Delaware, Newark Delaware USA

    2017-04-01

    Particulate phosphorus (PP) in the water column is an essential component of phosphorus (P) cycling in aquatic ecosystems yet its composition and transformations remain largely uncharacterized. To understand the roles of suspended particulates on regeneration of inorganic P (Pi) into the water column as well as sequestration into more stable mineral precipitates, we studied seasonal variation in both organic and inorganic P speciation in suspended particles in three sites in the Chesapeake Bay using sequential P extraction, 1D (31P) and 2D (1H-31P) nuclear magnetic resonance (NMR) spectroscopies, and electron microprobe analyses (EMPA). Remineralization efficiency of particulate P average 8% and 56% in shallow and deep sites respectively, suggesting the importance of PP remineralization is in resupplying water column Pi. Strong temporal and spatial variability of organic P composition, distributions, and remineralization efficiency were observed relating to water column parameters such as temperature and redox conditions: concentration of orthophosphate monoesters and diesters, and diester-to-monoester (D/M) ratios decreased with depth. Both esters and the D/M ratios were lower in the hypoxic July and September. In contrast, pyrophosphate and orthophosphate increased with depth, and polyphosphates was high in the anoxic water column. Sequential extraction and EMPA analyses of the suspended particles suggest presence of Ca-bound phosphate in the water column. We hypothesize authigenic precipitation of carbonate fluorapatite and/or its precursor mineral(s) in Pi rich water column, supported by our thermodynamic calculations. Our results, overall, reveal the important role suspended particles play in P remineralization and P sequestration in the Chesapeake Bay water column, provide important implications on P bioavailability and P sinks in similar eutrophic coastal environments.

  14. 33 CFR 100.124 - Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York.

    Science.gov (United States)

    2010-07-01

    ... South Bay Cross Bay Swim, Great South Bay, New York. 100.124 Section 100.124 Navigation and Navigable... NAVIGABLE WATERS § 100.124 Maggie Fischer Memorial Great South Bay Cross Bay Swim, Great South Bay, New York... swimmer or safety craft on the swim event race course bounded by the following points: Starting Point...

  15. Evidence for high salinity of Early Cretaceous sea water from the Chesapeake Bay crater.

    Science.gov (United States)

    Sanford, Ward E; Doughten, Michael W; Coplen, Tyler B; Hunt, Andrew G; Bullen, Thomas D

    2013-11-14

    High-salinity groundwater more than 1,000 metres deep in the Atlantic coastal plain of the USA has been documented in several locations, most recently within the 35-million-year-old Chesapeake Bay impact crater. Suggestions for the origin of increased salinity in the crater have included evaporite dissolution, osmosis and evaporation from heating associated with the bolide impact. Here we present chemical, isotopic and physical evidence that together indicate that groundwater in the Chesapeake crater is remnant Early Cretaceous North Atlantic (ECNA) sea water. We find that the sea water is probably 100-145 million years old and that it has an average salinity of about 70 per mil, which is twice that of modern sea water and consistent with the nearly closed ECNA basin. Previous evidence for temperature and salinity levels of ancient oceans have been estimated indirectly from geochemical, isotopic and palaeontological analyses of solid materials in deep sediment cores. In contrast, our study identifies ancient sea water in situ and provides a direct estimate of its age and salinity. Moreover, we suggest that it is likely that remnants of ECNA sea water persist in deep sediments at many locations along the Atlantic margin.

  16. Source and spatial distributions of particulate organic carbon and its isotope in surface waters of Prydz Bay, Antarctica, during summer

    Institute of Scientific and Technical Information of China (English)

    YIN Xijie; LI Yunhai; QIAO Lei; WANG Aijun; XU Yonghang; CHEN Jian

    2014-01-01

    In this study, we investigated the distributions of sea-surface suspended particulate organic carbon (POC) and its stable isotope (δ13CPOC) in Prydz Bay, Antarctica, and examined the factors influencing their distribution, sources, and transport. We used measurements collected from 61 stations in Prydz Bay during the 29th Chinese National Antarctic Research Expedition, in combination with remote sensing data on sea surface temperature (SST), chlorophyll a concentration, and sea ice coverage. The POC concentration in the surface waters of Prydz Bay was 0.28-0.84 mg·L-1, with an average concentration of 0.48 mg·L-1. Theδ13CPOC value ranged from-29.68‰to-26.30‰, with an average of-28.01‰. The concentration of suspended POC was highest in near-shore areas and in western Prydz Bay. The POC concentration was correlated with chlorophyll a concentration and sea ice coverage, suggesting that POC was associated with phytoplankton production in local water columns, while the growth of phytoplankton was obviously affected by sea ice coverage. Theδ13CPOC value in suspended particles decreased gradually towards the outer waters of Prydz Bay, while in eastern Prydz Bay theδ13CPOC value become gradually more negative from nearshore to deep-water areas, suggesting thatδ13CPOC was mainly influenced by CO2 fixation by phytoplankton. Theδ13CPOC value in suspended particles near Zhongshan Station was significantly negative, possibly as a result of the input of terrigenous organic matter and changes in the phytoplankton species composition in the nearshore area.

  17. Sediment Pore Water Ammonium Concentrations in Old Tampa Bay as Determined by the Diffusive Equilibration in Thin Films (DET) Technique

    Science.gov (United States)

    Increased nitrogen loading, associated with rapid human population growth, was thought to be a major driver of Tampa Bay water quality degradation in the decades immediately after the Second World War. Improvements in wastewater treatment in the early 1980s led to marked reductio...

  18. Quantifying Relationships between Water Quality and Aquatic Life Use Attainment using Sediment Profile Imagery (SPI) in Pensacola Bay

    Science.gov (United States)

    We present results from a monthly sediment and water quality survey of nine stations along a transect in the Pensacola Bay estuary spanning the salinity gradient from Escambia River to the Gulf of Mexico. We evaluated Benthic Habitat Quality (Nilsson and Rosenberg 1997) derived f...

  19. Corrosion of metals and alloys in the coastal and deep waters of the Arabian Sea and the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sawant, S.S.; Venkat, K.; Wagh, A.B.

    Corrosion rate of mild steel (MS), stainless steel (SS), copper, brass and cupro-nickel has been determinEd. by exposing metallic coupons in coastal and oceanic waters of the Arabian Sea and Bay of Bengal. Amongst the metals and alloys under study...

  20. Persistence and growth of faecal culturable bacterial indicators in water column and sediments of Vidy Bay, Lake Geneva, Switzerland

    Institute of Scientific and Technical Information of China (English)

    POTE John; HALLER Laurence; KOTTELAT Régis; SASTRE Vincent; ARPAGAUS Philippe; WILDI Walter

    2009-01-01

    The aims of this study was to investigate the persistence and the growth of culturable bacterial indicators (CBI) including total coliforms (TC) and faecal coliforms represented by E. coli, enterococcus (ENT), and aerobic mesophilic bacteria (AMB) in the surface sediments and the water column of the Bay of Vidy (Lake Geneva, City of Lausanne, Switzerland). The study was carried out for 60 d using microcosms containing Sewage Treatment Plant (STP) effluent water and non-sterile water without CBI, as well as contaminated and non-contaminated sediments. The effects of water temperature and of organic matter associated with sediments on the survival of CBI in the sediments and the water column were observed. The number of CBI colonies in the contaminated sediments of Vidy Bay and in the STP effluent water was almost identical in the order of 105--107, 104--106, 103--105, and 104--107 CFU/100 g sediment or /100 mL water for TC, E. coli, ENT, and AMB respectively. A degradation of CBI was observed in the sediments where organic mater content was low and in the water column at a temperature of 10℃ after 5 d of experimentation. In addition, a growth of CBI was observed in the sediment which is rich in organic matter at a temperature of 20℃. The results of this study indicate: (1) the higher concentrations of the CBI observed in different points in the water column of Vidy Bay may not be explained only by the recent contribution of the three potential sources of the Bay contamination including STP and the Chamberonne and Flon Rivers, but also by the persistence, removal from sediment and multiplication of CBI in the sediment and water column; (2) the sediment of Vidy Bay constitute a reservoir of CBI and can even support their growth. (3) the CBI not only survive in sediments, but also can be remobilized and increased in the water column, therefore it become a permanent microbiological pollution in Vidy Bay.

  1. Chemometry use in the evaluation of the sanya bay water quality

    Directory of Open Access Journals (Sweden)

    Jun-De Dong

    2010-12-01

    Full Text Available In this study, chemometric method is employed to identify anthropogenic effects on the water quality in Sanya Bay, South China Sea, and its marine and natural characteristics. Principal component analysis has extracted the four latent factors, thus explaining 85.52% of the total variance. Cluster analysis and principal component analysis have identified three different patterns of water quality based on anthropogenic effects and marine characteristics: Cluster I located in the outer and middle parts of the bay, Cluster II close to downtown Sanya, Cluster III located in the Sanya River estuary. In terms of the temporal pattern, principal component analysis and cluster analysis have distinguished the dry season from November to the following April, and the rainy season from May to October. The temporal pattern is related to climate and natural characteristics. The similarity index between variables and scores of samples can further distinguish the contribution of the variables to the samples. Both the polluting sources external to the Sanya River and the water from the South China Sea exercise an important influence on the water quality in Sanya Bay. These results may be valuable for socioeconomic development and human health in the Sanya Bay area.No presente estudo foi realizada a identificação dos efeitos antropogênicos e das características naturais marinhas das águas da Baía de Sanya, situada ao sul do Mar da China, através de método quimiométrico. A análise de componentes principais (PCA aplicada aos dados extraiu quatro eixos que explicaram 85,52% da variância total dos dados. Através das análises de Agrupamento e PCA foram identificados três padrões diferentes de qualidade das águas, baseados nos efeitos antropogênicos e nas características marinhas: Grupo I, localizado nas partes externa e mediana da baía; Grupo II, próximo do centro urbano de Sanya; Grupo III, localizado no estuário do Rio Sanya. Quanto ao padr

  2. Trace metal variability in coastal waters of San Jorge Bay, Antofagasta, Chile: An environmental evaluation and statistical approach to propose local background levels.

    Science.gov (United States)

    Valdés, J; Román, D; Guiñez, M; Rivera, L; Ávila, J; Cortés, P; Castillo, A

    2015-11-15

    Between 2008 and 2011, twelve metals from 384 coastal waters samples from San Jorge Bay (Antofagasta, northern Chile) were collected and analyzed. The goal was to evaluate the quality of the bay's water bodies according to the current Chilean Quality Guideline and to establish background levels for these metals. The result suggests that the coastal waters of San Jorge Bay are of very good quality suitable for recreational activities involving human body contact. The natural background thresholds established for this bay were significantly lower than primary and secondary water quality guidelines. The distribution of Cu, Zn and Pb, along the bay's coastline provides evidence of the effects of industrial activity. Both situations suggest that the threshold indicated in the environmental guidelines of the Chilean legislation may be overestimated and do not represent pollution-free environments.

  3. Air-water greenhouse gases exchange in two coastal systems in Cadiz Bay (SW Spain)

    Science.gov (United States)

    Burgos, Macarena; Ortega, Teodora; Forja, Jesús

    2014-05-01

    Coastal areas are subject to a great anthropogenic pressure because more than half of the world's population lives in its vicinity, causing organic matter inputs, which intensifies greenhouse gas emissions into the atmosphere. Water surface greenhouse gas concentrations (CH4 and N2O) have been estimated in two aquatic systems of Cadiz Bay Natural Park: Rio San Pedro Creek and Sancti Petri Channel Water renewal in Rio San Pedro Creek is tidally controlled. Due to its little freshwater input, the Creek is essentially a marine system. Several fish farms are distributed on its banks discharging effluents without previous treatment. Nine sampling stations are distributed along this system 12 Km length. Sancti Petri Channel is a flow channel-ebb tides extending from the inner Cadiz Bay to the Atlantic Ocean along 17 Km. Organic matter pollution sources in this environment are straggly. There exist anthropogenic inputs such as aquaculture effluents and sewage discharges coming through the Iro River, which flows into the Channel central part. In addition there are natural organic matter inputs from surrounding marshes. It has been established 11 sampling stations crossing this system. Sampling was conducted seasonally during 2013. CH4 and N2O concentrations were obtained though a gas chromatograph connected to an equilibration system. Greenhouse gas values vary between 24 and 295 nM and 16 and 27 nM for CH4 and N2O, respectively. Gas concentrations increase close to the fish farm effluent in Rio San Pedro Creek, and next to Iro River's mouth in Sancti Petri tidal Channel. Both environments act as greenhouse gas sources into the atmosphere, showing seasonal variations. It has been estimated mean fluxes of 75.3 μmol m-2 d-1 of CH4 and 31.9 μmol m-2 d-1 of N2O for both systems.

  4. Surface water subduction during a downwelling event in a semienclosed bay

    Science.gov (United States)

    Barton, E. D.; Torres, R.; Figueiras, F. G.; Gilcoto, M.; Largier, J.

    2016-09-01

    The Ría de Vigo is a bay strongly influenced by upwelling-downwelling cycles along the adjacent coast of NW Iberia. Moored and ship-board observations during September 2006 showed that subduction, initially associated with an estuarine circulation, strengthened when a strong downwelling circulation, resulting from northward wind over the coastal ocean, was generated in the outer Ría causing ambient waters to be advected outward in the lower layer. Incoming surface waters confined the estuarine circulation to the shallow interior and displaced isopleths downward through the water column at ˜10 m d-1. As the estuarine circulation retreated inward, strong flow convergence developed between middle and inner ria in the layer above 15 m, while divergence developed beneath. The convergence increased through the period of downwelling-favorable wind at a rate consistent with the observed isopleth displacement velocities. The coefficient of turbulent diffusion Kt, from a microstructure profiler, indicated that mixing was strong in the estuarine circulation and subsequently in the downwelling zone, where localized instabilities and temperature-salinity inversions were observed. During the downwelling, concentrations of phytoplankton, including potentially harmful species, increased, especially in the middle and inner ria, as a result of inward advection, subduction, and the ability of the dinoflagellates to maintain their position in the water column by swimming. In the course of the 5 day event, the water mass of all but the innermost Ría was flushed completely and replaced by waters originating in the coastally trapped poleward flow along the Atlantic coastline.

  5. Three-Dimensional Shallow Water Adaptive Hydraulics (ADH-SW3) Validation: Galveston Bay Hydrodynamics and Salinity Transport

    Science.gov (United States)

    2015-04-01

    Salinity Transport Co as ta l a nd H yd ra ul ic s La bo ra to ry Gaurav Savant and R. Charlie Berger April 2015 Approved for public release...Three-Dimensional Shallow Water Adaptive Hydraulics (ADH-SW3) Validation Report 1: Galveston Bay Hydrodynamics and Salinity Transport Gaurav...water surface elevations, velocities, and salinity . DISCLAIMER: The contents of this report are not to be used for advertising, publication, or

  6. Multivariate statistical analysis of water quality and phytoplankton characteristics in Daya Bay, China, from 1999 to 2002

    Directory of Open Access Journals (Sweden)

    You-Shao Wang

    2006-06-01

    Full Text Available This study analyzed seasonal physicochemical and phytoplanktondata collected at 12 marine monitoring stations in Daya Bay from1999 to 2002. Cluster analysis based on water quality and phytoplanktonparameters measured at the 12 stations could be grouped intothree clusters: cluster I - stations S1, S2, S7 and S11 in thesouthern part and the north-eastern part of Daya Bay; clusterII - stations S5, S6, S9, S10 and S12 in the central and north-easternparts of Daya Bay; cluster III - stations S3, S4 and S8 in the cageculture areas in the south-western part of Daya Bay and in thenorth-western part of the Bay near Aotou harbor. Bivariate correlationsbetween phytoplankton density and the major physical and nutrientfactors were calculated for all stations. Factor analysis showsthat there were high positive loadings of pH, TIN and the ratioof TIN to PO4-P in the three clusters, which indicates thatall the stations in the three clusters were primarily groupedaccording to their respective nutrient conditions.

  7. Risk assessment for produced water discharges to Louisiana open bays. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.

    1996-03-22

    The US Department of Energy (USDOE) has a program of research in the environmental aspects of oil and gas extraction. This sampling project will characterize the environmental impacts associated with the discharge of naturally occurring radioactive materials (NORM), metals and organics in produced water. This report is part of a series of studies of the health and ecological risks from discharges of produced water to the Gulf of Mexico, supported by the USDOE. These assessments are being coordinated with the field study, using the collected data to perform human health and ecological risk assessments. These assessments will provide input to regulators in the development of guidelines and permits, and to industry in the development and use of appropriate discharge practices. The initial human health and ecological risk assessments consist of conservative screening analyses meant to identify potentially important contaminants, and to eliminate others from further consideration. More quantitative assessments were done for contaminants identified, in the screening analysis, as being of potential concern. Section 2 gives an overview of human health and ecological risk assessment to help put the analyses presented here in perspective. Section 3 provides the hazard assessment portion of the risk assessment, and identifies the important receptors and pathways of concern. Section 3 also outlines the approach taken to the risk assessments presented in the rest of the report. The remaining sections (4 through 9) present the human health and ecological risk assessments for discharges of produced water to open bays in Louisiana.

  8. NASA Satellite Monitoring of Water Clarity in Mobile Bay for Nutrient Criteria Development

    Science.gov (United States)

    Blonski, Slawomir; Holekamp, Kara; Spiering, Bruce A.

    2009-01-01

    This project has demonstrated feasibility of deriving from MODIS daily measurements time series of water clarity parameters that provide coverage of a specific location or an area of interest for 30-50% of days. Time series derived for estuarine and coastal waters display much higher variability than time series of ecological parameters (such as vegetation indices) derived for land areas. (Temporal filtering often applied in terrestrial studies cannot be used effectively in ocean color processing). IOP-based algorithms for retrieval of diffuse light attenuation coefficient and TSS concentration perform well for the Mobile Bay environment: only a minor adjustment was needed in the TSS algorithm, despite generally recognized dependence of such algorithms on local conditions. The current IOP-based algorithm for retrieval of chlorophyll a concentration has not performed as well: a more reliable algorithm is needed that may be based on IOPs at additional wavelengths or on remote sensing reflectance from multiple spectral bands. CDOM algorithm also needs improvement to provide better separation between effects of gilvin (gelbstoff) and detritus. (Identification or development of such algorithm requires more data from in situ measurements of CDOM concentration in Gulf of Mexico coastal waters (ongoing collaboration with the EPA Gulf Ecology Division))

  9. Novel Finding of Widespread Occurrence and Accumulation of Bisphenol A Diglycidyl Ethers (BADGEs) and Novolac Glycidyl Ethers (NOGEs) in Marine Mammals from the United States Coastal Waters.

    Science.gov (United States)

    Xue, Jingchuan; Kannan, Kurunthachalam

    2016-02-16

    Bisphenol A diglycidyl ether (BADGE)- and bisphenol F diglycidyl ether (BFDGE)-based epoxy resins have a broad range of applications, including serving as inner coatings of food and beverage cans and as protective coatings in marine construction. Prior to this study, no studies had examined the occurrence and bioaccumulation of BADGEs or BFDGEs in aquatic organisms. In this study, BADGE, BFDGE, and nine of their derivatives were determined in 121 tissue (liver, kidney, blubber, and brain) samples from eight species of marine mammals collected from the U.S. coastal waters of Florida, California, Washington, and Alaska. BADGE·2HCl was the predominant compound found in the majority (78.5%) of the marine mammal tissues analyzed, at concentrations of up to 2950 ng/g (wet weight (wt)) found in the liver of a sea otter from Kachemak Bay, Alaska. The measured concentrations of BADGE·2HCl in marine mammals were on the order of hundreds of nanograms per gram tissue, which are some of the highest concentrations ever reported for this compound in biota. Males contained greater concentrations of BADGE·2HCl than did females. BADGE·2HCl also was found in the brain tissues of sea otters. Trace levels of BADGE·2HCl were found in the livers of polar bears from Alaska, which suggested that BADGEs are widely distributed in the oceanic environment.

  10. Bioavailability of heavy metals in water and sediments from a typical Mediterranean Bay (Málaga Bay, Region of Andalucía, Southern Spain).

    Science.gov (United States)

    Alonso Castillo, M L; Sánchez Trujillo, I; Vereda Alonso, E; García de Torres, A; Cano Pavón, J M

    2013-11-15

    Concentrations of heavy metals were measured in sediment and water from Málaga Bay (South Spain). In the later twentieth century, cities such as Málaga, have suffered the impact of mass summer tourism. The ancient industrial activities, and the actual urbanization and coastal development, recreation and tourism, wastewaters treatment facilities, have been sources of marine pollution. In sediments, Ni was the most disturbing metal because Ni concentrations exceeded the effects range low (ERL), concentration at which toxicity could start to be observed in 85% of the samples analyzed. The metal bioavailability decreased in the order: Cd>Ni>Pb>Cu>Cr. In the sea water samples, Cd and Pb were the most disturbing metals because they exceeded the continuous criteria concentration (CCC) of US EPA in a 22.5% and 10.0% of the samples, respectively. Statistical analyses (ANOVA, PCA, CA) were performed. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Water mass bio-optical properties in the Monterey Bay region: Fluorescence-based inference of shifts in phytoplankton photophysiology

    Science.gov (United States)

    Jolliff, J. K.; Gould, R. W., Jr.; Penta, B.; Teague, W. J.; DeRada, S.; Chavez, F. P.; Arnone, R. A.

    2012-07-01

    A physical and bio-optical field survey of the Monterey Bay area was conducted during May-June 2008. The combined bio-optical and physical data may be summarized as a transition between two end-member states during the late spring to summer upwelling season: (1) the mesotrophic, nanoflagellate-dominated, low-salinity surface waters (chlorophyll-a ˜ 0.5-2 mg m-3; S 2 mg m-3; S > 33.8) of Monterey Bay and adjacent continental shelf areas. High-resolution and collocated spectrophotometric, fluorometric and CTD data obtained from a towed platform indicated low-salinity subarctic-origin surface waters intruded into Monterey Bay on 4 June. The dark in vivo fluorometry (IVF) phytoplankton response normalized to particle absorption at 676 nm (the apparent fluorescence efficiency, AFE) was nearly fourfold larger in this water mass type compared to higher salinity surface waters more typical of Monterey Bay. The collocated fluorescence and optical data were then used to estimate in situ irradiance values and determine apparent light saturation intensities (I'k) based on the remarkably consistent AFE water column inflection points. I'kvalues retrieved from the low-salinity surface waters were approximately half those obtained over the continental shelf. An analysis of concomitant HPLC data, in addition to historical data for the region, suggest these observed fluorescence trends may be indicative of taxon-specific variation in photophysiology. Specifically, the subarctic water mass-associated pelagic nanoflagellate group likely possesses a fundamentally different photosynthetic architecture than large diatoms prototypical of coastal upwelling regimes.

  12. The evolution of water property in the Mackenzie Bay polynya during Antarctic winter

    Science.gov (United States)

    Xu, Zhixin; Gao, Guoping; Xu, Jianping; Shi, Maochong

    2017-10-01

    Temperature and salinity profile data, collected by southern elephant seals equipped with autonomous CTD-Satellite Relay Data Loggers (CTD-SRDLs) during the Antarctic wintertime in 2011 and 2012, were used to study the evolution of water property and the resultant formation of the high density water in the Mackenzie Bay polynya (MBP) in front of the Amery Ice Shelf (AIS). In late March the upper 100-200 m layer is characterized by strong halocline and inversion thermocline. The mixed layer keeps deepening up to 250 m by mid-April with potential temperature remaining nearly the surface freezing point and sea surface salinity increasing from 34.00 to 34.21. From then on until mid-May, the whole water column stays isothermally at about -1.90℃ while the surface salinity increases by a further 0.23. Hereafter the temperature increases while salinity decreases along with the increasing depth both by 0.1 order of magnitude vertically. The upper ocean heat content ranging from 120.5 to 2.9 MJ m-2, heat flux with the values of 9.8-287.0 W m-2 loss and the sea ice growth rates of 4.3-11.7 cm d-1 were estimated by using simple 1-D heat and salt budget methods. The MBP exists throughout the whole Antarctic winter (March to October) due to the air-sea-ice interaction, with an average size of about 5.0×103 km2. It can be speculated that the decrease of the salinity of the upper ocean may occur after October each year. The recurring sea-ice production and the associated brine rejection process increase the salinity of the water column in the MBP progressively, resulting in, eventually, the formation of a large body of high density water.

  13. Environmental setting of deep-water oysters in the Bay of Biscay

    Science.gov (United States)

    Van Rooij, D.; De Mol, L.; Le Guilloux, E.; Wisshak, M.; Huvenne, V. A. I.; Moeremans, R.; Henriet, J.-P.

    2010-12-01

    We report the northernmost and deepest known occurrence of deep-water pycnodontine oysters, based on two surveys along the French Atlantic continental margin to the La Chapelle continental slope (2006) and the Guilvinec Canyon (2008). The combined use of multibeam bathymetry, seismic profiling, CTD casts and a remotely operated vehicle (ROV) made it possible to describe the physical habitat and to assess the oceanographic control for the recently described species Neopycnodonte zibrowii. These oysters have been observed in vivo in depths from 540 to 846 m, colonizing overhanging banks or escarpments protruding from steep canyon flanks. Especially in the Bay of Biscay, such physical habitats may only be observed within canyons, where they are created by both long-term turbiditic and contouritic processes. Frequent observations of sand ripples on the seabed indicate the presence of a steady, but enhanced bottom current of about 40 cm/s. The occurrence of oysters also coincides with the interface between the Eastern North Atlantic Water and the Mediterranean Outflow Water. A combination of this water mass mixing, internal tide generation and a strong primary surface productivity may generate an enhanced nutrient flux, which is funnelled through the canyon. When the ideal environmental conditions are met, up to 100 individuals per m² may be observed. These deep-water oysters require a vertical habitat, which is often incompatible with the requirements of other sessile organisms, and are only sparsely distributed along the continental margins. The discovery of these giant oyster banks illustrates the rich biodiversity of deep-sea canyons and their underestimation as true ecosystem hotspots.

  14. Influence of Conowingo Reservoir Infill on Chesapeake Bay Deep Water Hypoxia

    Science.gov (United States)

    Linker, L. C.; Cerco, C. F.; Batiuk, R.

    2014-12-01

    The Chesapeake Bay Total Maximum Daily Load (TMDL) requires the reduction of nitrogen, phosphorus, and sediment loads in the Chesapeake watershed because of the tidal water quality impairments and the damage to living resources they cause. Within the Chesapeake watershed the Conowingo Reservoir has been filling in with sediment for almost a century, and is now in a state of near-full capacity called dynamic equilibrium. The development of the Chesapeake TMDL in 2010 was with the hydrology of a 1991-2000 simulation period, and carried with this simulation period the implicit model calibration assumption, based on the 1991-2000 nutrient and sediment observations, of a Conowingo Reservoir that was still effectively trapping sediment. In a TMDL, pollutant loads beyond the TMDL allocation, which are brought about by growth or other conditions, must be offset. Using the analysis tools of the Chesapeake TMDL for assessing the degree of attainment of living resource based water quality standards, the estimated nutrient and sediment loads from a simulated infill of the Conowingo Reservoir was determined. The influence on Chesapeake water quality by a large storm and scour event of January 1996 on the Susquehanna was estimated and the same storm and scour events were also evaluated in the more critical living resource periods of June and October. An analysis was also made on the estimated influence of more moderate but frequent high flow events. The infill of the Conowingo reservoir had estimated impairments of water quality at both the simulated high flow scour events and at the more frequent moderate storm flows. The estimated impairment was primarily on the deep water and deep channel dissolved oxygen because of increased scour and transport of dissolved particulate organic nutrients under conditions of Conowingo infill. Figure 1 describes the linked models used to assess the impact of Conowingo Reservoir infill on Chesapeake hypoxia.

  15. Gas exchange rates across the sediment-water and air-water interfaces in south San Francisco Bay

    Science.gov (United States)

    Hartman, Blayne; Hammond, Douglas E.

    1984-01-01

    Radon 222 concentrations in the water and sedimentary columns and radon exchange rates across the sediment-water and air-water interfaces have been measured in a section of south San Francisco Bay. Two independent methods have been used to determine sediment-water exchange rates, and the annual averages of these methods agree within the uncertainty of the determinations, about 20%. The annual average of benthic fluxes from shoal areas is nearly a factor of 2 greater than fluxes from the channel areas. Fluxes from the shoal and channel areas exceed those expected from simple molecular diffusion by factors of 4 and 2, respectively, apparently due to macrofaunal irrigation. Values of the gas transfer coefficient for radon exchange across the air-water interface were determined by constructing a radon mass balance for the water column and by direct measurement using floating chambers. The chamber method appears to yield results which are too high. Transfer coefficients computed using the mass balance method range from 0.4 m/day to 1.8 m/day, with a 6-year average of 1.0 m/day. Gas exchange is linearly dependent upon wind speed over a wind speed range of 3.2–6.4 m/s, but shows no dependence upon current velocity. Gas transfer coefficients predicted from an empirical relationship between gas exchange rates and wind speed observed in lakes and the oceans are within 30% of the coefficients determined from the radon mass balance and are considerably more accurate than coefficients predicted from theoretical gas exchange models.

  16. Integrating Sensor Data and Informatics to Improve Understanding of Hypoxia in the WATERS Network Testbed at Corpus Christi Bay, Texas

    Science.gov (United States)

    Coopersmith, E.; Kulis, P.; Brouwer, A.; Montagna, P.; Hodges, B. R.; Minsker, B.; Maidment, D.

    2007-12-01

    The goal of the WATERS Network Testbed in Corpus Christi Bay (Texas) is to better understand hypoxia by creating a prototype Environmental Information System (EIS) that links field data collection, real-time modeling techniques, and cyberinfrastructure. In this paper, we explore the connection between the bay's bottom-water hypoxia and wind mixing by integrating several field data sets within a machine-learning model and exploring the mechanisms leading to the model results using an independent data set. K-nearest neighbor machine learning models applied to several long-term data sets indicate that wind velocities are instrumental in forecasting hypoxic events. Additionally, statistical analysis suggests that the impacts of wind vary spatially throughout the bay. Forecasting algorithms can be employed to predict not only the expected value of dissolved oxygen levels throughout the bay, but also the probability of observing hypolimnetic hypoxia. Prior values of dissolved oxygen, salinity, wind direction, wind velocity, and water temperature have been shown to play a meaningful role in influencing the DO value twenty-four hours hence. Visualizing spatial maps of expected means and variances not only illustrate potentially hypoxia regions, but areas where future sampling would be most beneficial as well. We use a short-term field data set to explore the possible mechanisms controlling the observed statistical trends in long-term data sets. Field data taken from July 2006 document a specific hypoxic episode that follows a high wind event. Analyses of temporal changes in the vertical water column support the suspected connections between wind, salinity, and hypoxia, and suggest some possible mechanisms for this connection. It is suspected that wind controls the sinking of heavy, saline water into the bottom of Corpus Christi Bay from Laguna Madre, a nearby shallower bay. This isolation of dense water from surface oxygen replenishment may be critical in hypoxia

  17. Temporal changes in TBT pollution in water, sediment, and oyster from Jinhae Bay after the total ban in South Korea.

    Science.gov (United States)

    Kim, Nam Sook; Hong, Sang Hee; Yim, Un Hyuk; Shin, Kyung-Hoon; Shim, Won Joon

    2014-09-15

    Temporal change in tributyltin (TBT) levels in Jinhae Bay, which has various TBT sources, was investigated in water, sediments, and oysters from 2003 to 2013 after its total ban in South Korea. The seawater TBT levels decreased over 500-fold from 1995/97 to 2008/09. The oyster TBT levels were about fourfold lower in 2012/13 than in 1995/97. However, the sediment TBT levels did not significantly change, even 10 years after the partial TBT ban on small ships and 7 years after the total TBT ban on all oceangoing vessels in Korea. The total ban of TBT use effectively reduced water and oyster TBT levels in Jinhae Bay, but TBT levels in water, oysters, and sediment remained above the global environmental quality standards established to protect marine organisms.

  18. A continuous, real-time water quality monitoring system for the coral reef ecosystems of Nanwan Bay, Southern Taiwan.

    Science.gov (United States)

    Tew, Kwee Siong; Leu, Ming-Yih; Wang, Jih-Terng; Chang, Chia-Ming; Chen, Chung-Chi; Meng, Pei-Jie

    2014-08-30

    The coral reef ecosystems of Nanwan Bay, Southern Taiwan are undergoing degradation due to anthropogenic impacts, and as such have resulted in a decline in coral cover. As a first step in preventing the continual degradation of these coral reef environments, it is important to understand how changes in water quality affect these ecosystems on a fine-tuned timescale. To this end, a real-time water quality monitoring system was implemented in Nanwan Bay in 2010. We found that natural events, such as cold water intrusion due to upwelling, tended to elicit temporal shifts in coral spawning between 2010 and 2011. In addition, Degree Heating Weeks (DHWs), a commonly utilized predictor of coral bleaching, were 0.92 and 0.59 in summer 2010 and 2011, respectively. Though this quantity of DHW was below the presumed stress-inducing value for these reefs, a rise in DHWs in the future may stress the resident corals.

  19. Final Report: Risk assessment for produced water discharges to Louisiana open bays

    Energy Technology Data Exchange (ETDEWEB)

    Meinhold, A.F.; DePhillips, M.P.; Holtzman, S.

    1996-03-01

    Potential human health and environmental impacts from discharges of produced water to the Gulf of Mexico are of concern to regulators at the State and Federal levels, the public, environmental interest groups and industry. Current and proposed regulations require a zero discharge limit for coastal facilities, based primarily on studies in low energy, poorly flushed environments. However, produced water discharges in coastal Louisiana include a number of open bay sites, where potential human health and environmental impacts are likely to be smaller than those demonstrated for low energy canal environments, but greater than the minimal impacts associated with offshore discharges. Additional data and assessments are needed to support risk managers at the State and Federal levels in the development of regulations that protect human health and the environment without unnecessary cost to the economic welfare of the region and the nation. This project supports the Natural Gas and Oil Initiative objectives to: (1) improve coordination on environmental research; (2) streamline State and Federal regulation; (3) enhance State, and Federal regulatory decision making capability; (4) enhance dialogue through industry/government/public partnerships; and (5) work with States and Native American Tribes.

  20. Size-dependent photoacclimation of the phytoplankton community in temperate shelf waters (southern Bay of Biscay)

    KAUST Repository

    Álvarez, E

    2015-12-09

    © Inter-Research 2016. Shelf waters of the Cantabrian Sea (southern Bay of Biscay) are productive ecosystems with a marked seasonality. We present the results from 1 yr of monthly monitoring of the phytoplankton community together with an intensive sampling carried out in 2 contrasting scenarios during the summer and autumn in a mid-shelf area. Stratification was apparent on the shelf in summer, while the water column was comparatively well mixed in autumn. The size structure of the photoautotrophic community, from pico-to micro-phytoplankton, was tightly coupled with the meteo-climatic and hydrographical conditions. Over the short term, variations in the size structure and chlorophyll content of phytoplankton cells were related to changes in the physico-chemical environment, through changes in the availability of nutrients and light. Uncoupling between the dynamics of carbon biomass and chlorophyll resulted in chlorophyll to carbon ratios dependent on body size. The slope of the size dependence of chlorophyll content increased with increasing irradiance, reflecting different photoacclimation plasticity from pico-to micro-phytoplankton. The results have important implications for the productivity and the fate of biogenic carbon in this region, since the size dependence of photosynthetic rates is directly related to the size scaling of chlorophyll content.

  1. Effects of water exchange and vegetation on the macroinvertebrate fauna composition of shallow land-uplift bays in the Baltic Sea

    Science.gov (United States)

    Hansen, Joakim P.; Wikström, Sofia A.; Kautsky, Lena

    2008-04-01

    Shallow bays with soft sediment bottoms are common habitats along the Swedish and Finnish Baltic Sea coastline. These bays undergo a process of geomorphometric evolution with the natural isostatic land-uplift process, whereby open bays and sounds decrease in depth and are gradually isolated from the sea, forming bays with narrow openings. This study tested the relationship between the morphometric isolation of the bays from the sea and the macroinvertebrate fauna community of these bays. Additionally, we tested the specific role of the submerged vegetation as an indicator of the macroinvertebrate fauna community. We chose two environmental factors for the analyses, water exchange of the bays and the taxon richness of the macroflora in the bays. We found a hierarchical relationship between water exchange, flora taxon richness, and fauna biomass and taxon richness using structural equation modelling: decreased biomass and taxon richness of fauna were related to decreased flora taxon richness, which in turn was related to decreased water exchange. Using multivariate redundancy analysis, the two environmental factors included in the model were found to explain 47.7% of the variation in the fauna taxon composition and 57.5% of the variation in the functional feeding groups of the fauna. Along the morphometric isolation gradient of the bays, the fauna assemblages changed from a community dominated by gastropods, bivalves, and crustaceans, to a community mainly consisting of a few insect taxa. Moreover, the proportion of predators, gathering collectors, and shredders increased while that of filtering collectors and scrapers decreased. Our results indicate that the density and taxon richness of macroinvertebrate fauna are higher in less morphometrically isolated bays than in more isolated bays in the Baltic Sea. Furthermore, we suggest that the taxon richness of macroflora can serve as an indicator of the fauna community.

  2. 75 FR 38710 - Special Local Regulation, Fran Schnarr Open Water Championships, Huntington Bay, NY

    Science.gov (United States)

    2010-07-06

    ... Championships, Huntington Bay, NY'' in the Federal Register (75 FR 13454). The Coast Guard received no comments...-2009-0520) in the Federal Register (74 FR 51243). The notice proposed a regulated area encompassing 100... Bay, NY in the Federal Register (75 FR 13454). This notice proposes a 100 yard regulated area...

  3. Modeling the fate of p,p'-DDT in water and sediment of two typical estuarine bays in South China: Importance of fishing vessels' inputs.

    Science.gov (United States)

    Fang, Shu-Ming; Zhang, Xianming; Bao, Lian-Jun; Zeng, Eddy Y

    2016-05-01

    Antifouling paint applied to fishing vessels is the primary source of dichloro-diphenyl-trichloroethane (DDT) to the coastal marine environments of China. With the aim to provide science-based support of potential regulations on DDT use in antifouling paint, we utilized a fugacity-based model to evaluate the fate and impact of p,p'-DDT, the dominant component of DDT mixture, in Daya Bay and Hailing Bay, two typical estuarine bays in South China. The emissions of p,p'-DDT from fishing vessels to the aquatic environments of Hailing Bay and Daya Bay were estimated as 9.3 and 7.7 kg yr(-1), respectively. Uncertainty analysis indicated that the temporal variability of p,p'-DDT was well described by the model if fishing vessels were considered as the only direct source, i.e., fishing vessels should be the dominant source of p,p'-DDT in coastal bay areas of China. Estimated hazard quotients indicated that sediment in Hailing Bay posed high risk to the aquatic system, and it would take at least 21 years to reduce the hazards to a safe level. Moreover, p,p'-DDT tends to migrate from water to sediment in the entire Hailing Bay and Daya Bay. On the other hand, our previous research indicated that p,p'-DDT was more likely to migrate from sediment to water in the maricultured zones located in shallow waters of these two bays, where fishing vessels frequently remain. These findings suggest that relocating mariculture zones to deeper waters would reduce the likelihood of farmed fish contamination by p,p'-DDT.

  4. Influential factors on the exchange rate of dissolved inorganic nutrients at the sediment-water interface in Jiaozhou Bay, China

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Incubation experiments are carried out to study the exchange rates of dissolved inorganic nutrients including silicate, phosphate, ammonium, nitrite, and nitrate (vSiO3-Si, vPO4-P, vNH4-N, vNO2-N and vNO3-N) at the sediment-water interface in the Jiaozhou Bay. Major factors influencing the exchange rates are discussed in detail, which include the dissolved inorganic nutrient concentrations in porewater (Cpw), water and clay contents,and grain size of the sediments (CH2O, Cclay and GSsed). The results may provide insight into the dynamics of nutrient transport and the environmental capacity of nutrients in Jiaozhou Bay, and should be beneficial to solving the problems caused by excessive nutrient input this area.

  5. Continuous terrain model for water circulation studies, Barnegat Bay, New Jersey. (10 meter resolution, 32-bit GeoTIFF, UTM 18, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Water quality in the Barnegat Bay estuary along the New Jersey coast is the focus of a multidisciplinary research project begun in 2011 by the U.S. Geological Survey...

  6. Draft Permit & Supporting Documentation for the Northeast Gateway Energy Bridge Deepwater Port, Federal Waters of Massachusetts Bay (Modification to Existing Permit LNG Regasification Vessel/DWP Project)

    Science.gov (United States)

    List of draft permit & supporting documentation for the Northeast Gateway Energy Bridge Deepwater Port, Federal Waters of Massachusetts Bay (Modification to Existing Permit LNG Regasification Vessel/DWP Project).

  7. Public Hearing and Comment Period Documents for the Northeast Gateway Energy Bridge Deepwater, Federal Waters of Massachusetts Bay (Modification to Existing Permit LNG Regasification Vessel/DWP Project)

    Science.gov (United States)

    List of public hearing & comment period document(s) for the Northeast Gateway Energy Bridge Deepwater Port, Federal Waters of Massachusetts Bay (Modification to Existing Permit LNG Regasification Vessel/DWP Project).

  8. Water Quality and Sedimentation Data of the Coastal Intensive Site Network (CISNet) Long Term Monitoring Sites in Kaneohe Bay, Oahu, Hawaii from 1998 to 2001 (NODC Accession 0001473)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A long term project to monitor water quality and sediment processes in Kaneohe Bay was initiated in November 1998 and continued through July 2001. Four primary sites...

  9. Contaminant profiles for surface water, sediment, flora and fauna associated with the mangrove fringe along middle and lower East Tampa Bay

    Science.gov (United States)

    Contaminant concentrations are reported for surface water, sediment, seagrass, mangroves, Florida Crown conch, blue crabs and fish collected during 2010-2011 from the mangrove fringe along eastern Tampa Bay. Concentrations of trace metals, chlorinated pesticides, atrazine, total ...

  10. Continuous terrain model for water circulation studies, Barnegat Bay, New Jersey. (10 meter resolution, 32-bit GeoTIFF, UTM 18, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Water quality in the Barnegat Bay estuary along the New Jersey coast is the focus of a multidisciplinary research project begun in 2011 by the U.S. Geological...

  11. Polygon boundaries for source data of a continuous terrain model for water circulation studies: Barnegat Bay, New Jersey. (Esri polygon shapefile, Geographic, WGS 84)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — Water quality in the Barnegat Bay estuary along the New Jersey coast is the focus of a multidisciplinary research project begun in 2011 by the U.S. Geological...

  12. Temperature, salinity, and nutrients from near surface shallow water samples of Mamala Bay Project MB-9, Ecosystem Response Study, (1993-1994) on Oahu, Hawaii (NODC Accession 9900064)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Water quality at 10 recreational beaches in Mamala Bay and in the nearshore ocean were monitored over a period of 12 months in 1993-1994 to determine the impact of...

  13. Mussels as a bio-indicator of the environmental quality of the coastal water of the Boka Kotorska Bay (Montenegro

    Directory of Open Access Journals (Sweden)

    MIHAJLO JOVIĆ

    2011-06-01

    Full Text Available The Mediterranean blue mussel Mytilus galloprovincialis was used as a pollution level indicator in the Boka Kotorska Bay of the southeastern Adriatic on the Montenegrin coast. The ever-increasing urbanization and industrialization, combined with a poor sewage system, an increase in both marine and inland traffic, as well as insufficient water circulation in the Bay itself have resulted in some level of pollution. Since heavy metals are extremely toxic and do not easily undergo biodecomposition, the results of this study supply valuable information concerning the metal pollution of the marine environment in Boka Kotorska Bay. The concentrations of the investigated metals and non-metals accumulated in the mussels were determined during the fall of 2007 using Atomic Absorption Spectroscopy (AAS for Cr, Mn, Co, Ni, Cu, Cd, Hg, Pb, Sn and V, and Energy Dispersive X-ray Fluorescence (ED–XRF to determine the concentrations of Fe, Zn, Si, P, S, Cl, K and Ca. ED–XRF was also used to determine the levels of non-metals and elements present in high concentrations. Comparing the data from this study in relation to data from other regions for Mytilus galloprovincialis, the mussel sampled from the Boka Kotorska Bay showed a moderate level of pollution.

  14. Evidence for the existence of Persian Gulf water and Red Sea water in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Jain, V.; Shankar, D.; Vinayachandran, P.N.; Kankonkar, A.; Chatterjee, A.; Amol, P.; Almeida, A.M.; Michael, G.S.; Mukherjee, A.; Chatterjee, M.; Fernandes, R.; Luis, R.; Kamble, A.; Hegde, A.; Chatterjee, S.; Das, U.; Neema, C.P.

    the existence of RSW throughout the bay. PGW is marked by the presence of a salinity maximum at 200-450 m; in the southwestern bay, PGW can be distinguished from the salinity maximum due to ASHSW because of the intervening Arabian Sea Salinity Minimum...

  15. The relative importance of road density and physical watershed features in determining coastal marsh water quality in Georgian Bay.

    Science.gov (United States)

    Decatanzaro, Rachel; Cvetkovic, Maja; Chow-Fraser, Patricia

    2009-09-01

    We used a GIS-based approach to examine the influence of road density and physical watershed features (watershed size, wetland cover, and bedrock type) on water quality in coastal marshes of Georgian Bay, Ontario. We created a GIS that included landscape information and water-quality data from a 9-year synoptic survey of 105 coastal marshes covering 28 quaternary watersheds. Multiple regressions and partial correlations were used to discern confounding effects of human-induced (road density) versus natural physical watershed determinants of water quality. Road density was the dominant factor influencing many water quality variables, showing positive correlations with specific conductivity (COND), total suspended solids (TSS), and inorganic suspended solids (ISS) and a negative correlation with overall Water Quality Index scores. Road density also showed positive correlations with total nitrate nitrogen (TNN) and total phosphorus (TP). By comparison, larger watershed area was the main factor leading to elevated TP concentrations. The proportion of the watershed occupied by wetlands explained the largest amount of variation in TNN concentrations (negative correlation) and was also negatively correlated with COND and positively correlated with TSS and ISS when we controlled for road density. Bedrock type did not have a significant effect in any of the models. Our findings suggest that road density is currently the overriding factor governing water quality of coastal marshes in Georgian Bay during the summer low-flow period. We recommend that natural variation in physical watershed characteristics be considered when developing water quality standards and management practices for freshwater coastal areas.

  16. Uptake of Trace Elements in Aragonitic Otoliths of an Estuarine Dependent Fish, Spotted Seatrout, from surface waters of Chesapeake Bay.

    Science.gov (United States)

    Dorval, E.; Jones, C.; Hannigan, R.; Sako, A.

    2002-05-01

    Seagrass beds in Chesapeake Bay are critical habitats for early life stages of Spotted seatrout, {\\Cynoscion nebulosus}. Spotted seatrout spawn in surface waters in the Bay during late spring and thereafter their larvae settle in seagrass beds where the juveniles spend three to four months. These habitats provide refuge and food for larvae and juveniles, influencing growth, mortality, and survival rates. Identification of essential seagrass habitats for estuarine-dependent fish is of primary importance given the current decline in habitat quality. We hypothesized that the geochemistry of surface waters in Chesapeake Bay is different along both the latitudinal and longitudinal gradients, and that we could use trace elements in otoliths as a natural tag to differentiate survivors among seagrass beds. We investigated the relationship between water and otolith trace element chemistry and we present here some preliminary results. From July to September 2001 we collected surface waters during spring tide from seagrass beds and around the mouth of the Potomac, Rappahannock, and York river. Waters were filtered through a 0.45 uM filter and acidified to pH < 2 with ultrapure nitric acid. In September, we collected juvenile fish in seagrass beds along the Western and Eastern shores, Tangier and Smith Islands. From each individual fish one sagittal otolith was extracted, cleaned with milli-Q water, soaked for 5 minutes in ultrapure hydrogen peroxide, rinsed, and sonicated. All dried and cleaned otoliths were dissolved in ultrapure nitric acid. We used trace metal clean procedures to process both water and otoliths and trace elements were measured by sector field ICP-MS. Both waters and otoliths showed distinct chemical signatures among seagrass beds, and samples could be classified with high accuracy to their respective sites of collection. For most seagrass beds Ba/Ca, Rb/Ca, V/Ca showed inverse relationship between water and otolith whereas Sr/Ca was positively correlated

  17. Environmental water quality assessment in Guaratuba bay, state of Paraná, southern Brazil

    Directory of Open Access Journals (Sweden)

    Byanka Damian Mizerkowski

    2012-06-01

    Full Text Available An environmental assessment of the estuarine waters of Guaratuba bay, Paraná State, Brazil, is provided through the analysis of physical-chemical, biological and hydrographic dynamics. Twelve stations with a bi-monthly frequency (from October/2002 until August/2003 were sampled during spring and neap tides for the determination of pH, Secchi depth, CO2 saturation, dissolved oxygen, chlorophyll, suspended particulate matter and dissolved inorganic nutrients (nitrate, nitrite, ammonium, phosphate and silicate. Based on the evaluation of six parameters (chlorophyll, Secchi depth, CO2 saturation, dissolved inorganic nitrogen and phosphorus and dissolved oxygen, Guaratuba Bay shows a low to medium trophic status, i.e. from meso- to oligotrophic, and a predominant heterotrophic metabolism, meaning that respiration overcomes primary production. Horizontal stratification was observed during the rainy season, while during the dry season the system showed more homogeneous conditions. Inorganic and/or organic matter in Guaratuba Bay seem to be controlled mainly by the seasonality of precipitation and/ also by ebb and flood tidal phase variations.A dinâmica das variáveis físico-químicas, biológicas e hidrográficas, em escalas temporal e espacial, sua variabilidade e tendências, permite avaliar a qualidade ambiental de estuários. Esse trabalho descreve as flutuações da qualidade de água da Baía de Guaratuba, sul do Estado do Paraná. Foram amostrados doze pontos em campanhas bimensais (outubro/2002 a agosto/2003, em situação de sizígia e de quadratura, para a análise das variáveis pH, transparência, saturação de CO2, oxigênio dissolvido, clorofila-a, material particulado em suspensão e nutrientes inorgânicos dissolvidos (nitrato, nitrito, amônio, fosfato e silicato. Considerando as seis variáveis descritoras da qualidade de água (clorofila-a, profundidade de Secchi, saturação de CO2, fósforo e nitrogênio inorg

  18. 33 CFR 165.1122 - San Diego Bay, Mission Bay and their Approaches-Regulated navigation area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false San Diego Bay, Mission Bay and... Coast Guard District § 165.1122 San Diego Bay, Mission Bay and their Approaches—Regulated navigation... waters of San Diego Bay, Mission Bay, and their approaches encompassed by a line commencing at Point La...

  19. Experimental study of water desorption isotherms and thin-layer convective drying kinetics of bay laurel leaves

    Science.gov (United States)

    Ghnimi, Thouraya; Hassini, Lamine; Bagane, Mohamed

    2016-02-01

    The aim of this work is to determine the desorption isotherms and the drying kinetics of bay laurel leaves (Laurus Nobilis L.). The desorption isotherms were performed at three temperature levels: 50, 60 and 70 °C and at water activity ranging from 0.057 to 0.88 using the statistic gravimetric method. Five sorption models were used to fit desorption experimental isotherm data. It was found that Kuhn model offers the best fitting of experimental moisture isotherms in the mentioned investigated ranges of temperature and water activity. The Net isosteric heat of water desorption was evaluated using The Clausius-Clapeyron equation and was then best correlated to equilibrium moisture content by the empirical Tsami's equation. Thin layer convective drying curves of bay laurel leaves were obtained for temperatures of 45, 50, 60 and 70 °C, relative humidity of 5, 15, 30 and 45 % and air velocities of 1, 1.5 and 2 m/s. A non linear regression procedure of Levenberg-Marquardt was used to fit drying curves with five semi empirical mathematical models available in the literature, The R2 and χ2 were used to evaluate the goodness of fit of models to data. Based on the experimental drying curves the drying characteristic curve (DCC) has been established and fitted with a third degree polynomial function. It was found that the Midilli Kucuk model was the best semi-empirical model describing thin layer drying kinetics of bay laurel leaves. The bay laurel leaves effective moisture diffusivity and activation energy were also identified.

  20. What caused the rise of water level in the battle of Luermen bay in 1661? Tsunami, Storm surge, or Tide?

    Science.gov (United States)

    Wu, Tso-Ren; Wu, Han; Tsai, Yu-Lin

    2016-04-01

    In 1661, Chinese navy led by General Zheng Chenggong at the end of Ming Dynasty had a naval battle against Netherlands. This battle was not only the first official sea warfare that China confronted the Western world, but also the only naval battle won by Chinese Navy so far. This event was important because it changed the fate of Taiwan until today. One of the critical points that General Zheng won the battle was entering Luermen bay unexpected. Luermen bay was and is an extreme shallow bay with a 2.1m maximum water depth during the high tide, which was not possible for a fleet of 20,000 marines to across. Therefore, no defense was deployed from the Netherlands side. However, plenty of historical literatures mentioned a strange phenomenon that helped Chinese warships entered the Luermen bay, the rise of water level. In this study, we will discuss the possible causes that might rise the water level, e.g. Tsunami, storm surge, and high tide. We analyzed it based on the knowledge of hydrodynamics. We performed the newly developed Impact Intensify Analysis (IIA) for finding the potential tsunami sources, and the COMCOT tsunami model was adopted for the nonlinear scenario simulations, associated with the high resolution bathymetry data. Both earthquake and mudslide tsunamis were inspected. Other than that, we also collected the information of tide and weather for identifying the effects form high tide and storm surge. After the thorough study, a scenario that satisfy most of the descriptions in the historical literatures will be presented. The results will explain the cause of mysterious event that changed the destiny of Taiwan.

  1. Experimental study of water desorption isotherms and thin-layer convective drying kinetics of bay laurel leaves

    Science.gov (United States)

    Ghnimi, Thouraya; Hassini, Lamine; Bagane, Mohamed

    2016-12-01

    The aim of this work is to determine the desorption isotherms and the drying kinetics of bay laurel leaves ( Laurus Nobilis L.). The desorption isotherms were performed at three temperature levels: 50, 60 and 70 °C and at water activity ranging from 0.057 to 0.88 using the statistic gravimetric method. Five sorption models were used to fit desorption experimental isotherm data. It was found that Kuhn model offers the best fitting of experimental moisture isotherms in the mentioned investigated ranges of temperature and water activity. The Net isosteric heat of water desorption was evaluated using The Clausius-Clapeyron equation and was then best correlated to equilibrium moisture content by the empirical Tsami's equation. Thin layer convective drying curves of bay laurel leaves were obtained for temperatures of 45, 50, 60 and 70 °C, relative humidity of 5, 15, 30 and 45 % and air velocities of 1, 1.5 and 2 m/s. A non linear regression procedure of Levenberg-Marquardt was used to fit drying curves with five semi empirical mathematical models available in the literature, The R2 and χ2 were used to evaluate the goodness of fit of models to data. Based on the experimental drying curves the drying characteristic curve (DCC) has been established and fitted with a third degree polynomial function. It was found that the Midilli Kucuk model was the best semi-empirical model describing thin layer drying kinetics of bay laurel leaves. The bay laurel leaves effective moisture diffusivity and activation energy were also identified.

  2. Murky Waters The Bohai Bay oil spill brings China's marine liability laws into focus

    Institute of Scientific and Technical Information of China (English)

    WANG HAIRONG

    2011-01-01

    Scallop farmers in Laoting County in north China's Hebei Province had been unaware a catastrophe was approaching their farms south of the Bohai Bay until late June when they found millions of young scallops dead.

  3. Eureka Littoral Cell CRSMP Humboldt Bay Mean Monthly Maximum Water Elevation 2011

    Data.gov (United States)

    California Department of Resources — The Humboldt Bay Shoreline Assessment and LiDAR Analysis was conducted by field mapping the entire shoreline and assigning an unique segment identifier based on a...

  4. Detection of Harmful Algal Blooms in the Optically Complex Coastal Waters of the Kuwait Bay using Aqua-MODIS data

    Science.gov (United States)

    Manche, C. J.; Sultan, M.; Uddin, S.; Al-Dousari, A.; Chouinard, K.

    2013-12-01

    In the optically complex coastal marine waters of the Kuwait Bay, the propagation of Harmful Algal Blooms (HABs) has become a severe issue over the last decade affecting aquaculture a primary component of the Kuwaiti economy. Although several remote sensing based methods of algal bloom detection exist today, few may accurately detect the concentration and identify the type of HABs in Case II waters. The purpose of this study is: (1) assessment of the method that best detects and identifies algal blooms in general and HABs in particular, in the Kuwait Bay, and (2) identification of the factors controlling the occurrence of HABs. Fluorescence Line Height (FLH), Empirical, Bio-Optical, and Operational Methods as well as Ocean Colour 3 Band Ratio (OC3M), Garver-Siegel-Maritorena Model (GSM), and General Inherent Optical Property (GIOP) Chlorophyll-a (Chl-a) algorithms were applied to Moderate Resolution Imaging Spectroradiometer (MODIS) images acquired (07/2002 to 07/2012) over the Kuwait Bay and areas as far east as Shatt Al-Arab and as far south as N. 29.284 (Lat.), E. 50.047 (Long.) decimal degrees. In-situ data (bloom days: 50; sampling locations: 64) collected (09/1999 to 07/2011) from the Kuwait Bay was provided by the Kuwait Institute for Scientific Research and was used to test the reliability of the satellite-based inferences. Tasks accomplished and findings reached include: (1) comparison of in situ to estimated OC3M, GSM, and GIOP chlorophyll concentrations over the sampling locations for the time period 2002 to 2009 showed that OC3M outperformed the two other techniques in predicting the observed distribution and in replicating the measured concentration of the in-situ Chl-a data; (2) applying the OC3M algorithm to a total of 4039 scenes and using threshold values of 3, 4, and 5 mg/m3 Chl-a concentrations we inferred 371, 202, and 124 occurrences in the Kuwait Bay that met their respective threshold; (3) applying the operational method we successfully

  5. Water exchange between Algeciras Bay and the Strait of Gibraltar: A study based on HF coastal radar

    Science.gov (United States)

    Chioua, J.; Dastis, C.; González, C. J.; Reyes, E.; Mañanes, R.; Ruiz, M. I.; Álvarez, E.; Yanguas, F.; Romero, J.; Álvarez, O.; Bruno, M.

    2017-09-01

    This study analyses the water mass exchanges at subinertial scale between Algeciras Bay and the adjacent Strait of Gibraltar. The mechanisms triggering this exchange process is investigated with the aid of recently-acquired data on surface currents obtained using a system of HF coastal radars deployed on the eastern side of the Strait, and remotely-sensed images of sea surface temperature (SST) and chlorophyll from the MODIS sensor of the Aqua satellite. HF radar data on surface currents are analyzed by the application of real empirical orthogonal function (EOF) decomposition, which produces three EOF modes explaining more than 70% of the variance of the surface currents at the mouth of the Bay (modes 2, 3, and 6). Mode 2 is related to the fluctuations of the Atlantic Jet in the central zone of the Strait, mainly due to a combined effect of the atmospheric pressure fluctuations in the Western Mediterranean Sea and local wind in the eastern side of the Strait; mode 3 is related to the coastal currents induced by zonal wind forcing on the north-western coast of the Strait and Alboran Sea; and mode 6 seems to be related to water transport induced by winds blowing with a significant north component into and out of the Bay.

  6. Metatranscriptomic analyses of plankton communities inhabiting surface and subpycnocline waters of the Chesapeake Bay during oxic-anoxic-oxic transitions.

    Science.gov (United States)

    Hewson, Ian; Eggleston, Erin M; Doherty, Mary; Lee, Dong Yoon; Owens, Michael; Shapleigh, James P; Cornwell, Jeffrey C; Crump, Byron C

    2014-01-01

    We used metatranscriptomics to study the gene transcription patterns of microbial plankton (0.2 to 64 μm) at a mesohaline station in the Chesapeake Bay under transitions from oxic to anoxic waters in spring and from anoxic to oxic waters in autumn. Samples were collected from surface (i.e., above pycnocline) waters (3 m) and from waters beneath the pycnocline (16 to 22 m) in both 2010 and 2011. Metatranscriptome profiles based on function and potential phylogeny were different between 2010 and 2011 and strongly variable in 2011. This difference in variability corresponded with a highly variable ratio of eukaryotic to bacterial sequences (0.3 to 5.5), reflecting transient algal blooms in 2011 that were absent in 2010. The similarity between metatranscriptomes changed at a lower rate during the transition from oxic to anoxic waters than after the return to oxic conditions. Transcripts related to photosynthesis and low-affinity cytochrome oxidases were significantly higher in shallow than in deep waters, while in deep water genes involved in anaerobic metabolism, particularly sulfate reduction, succinyl coenzyme A (succinyl-CoA)-to-propionyl-CoA conversion, and menaquinone synthesis, were enriched relative to in shallow waters. Expected transitions in metabolism between oxic and anoxic deep waters were reflected in elevated levels of anaerobic respiratory reductases and utilization of propenediol and acetoin. The percentage of archaeal transcripts increased in both years in late summer (from 0.1 to 4.4% of all transcripts in 2010 and from 0.1 to 6.2% in 2011). Denitrification-related genes were expressed in a predicted pattern during the oxic-anoxic transition. Overall, our data suggest that Chesapeake Bay microbial assemblages express gene suites differently in shallow and deep waters and that differences in deep waters reflect variable redox states.

  7. Copepod omnivory in the North Water Polynya (Baffin Bay) during autumn: spatial patterns in lipid composition

    Science.gov (United States)

    Stevens, Catherine J.; Deibel, Don; Parrish, Christopher C.

    2004-11-01

    To deduce spatial patterns in copepod lipid composition and feeding strategy (i.e., degree of omnivory) in the North Water Polynya (Baffin Bay), three dominant species were sampled extensively over a broad geographical area (∼75-78°N; 77-69°W). Calanus hyperboreus CV, C. glacialis CV and Metridia longa females were collected in shallow and deep strata at 16 stations during autumn 1999 (August-October). Principal components analysis (PCA) revealed that all species fed omnivorously in the southeastern (SE) region of the polynya. Here, copepods generally had elevated levels of carnivorous (e.g., 18 : 1 (n - 9)), dinoflagellate (e.g., 18 : 4 (n - 3) ; 22 : 6 (n - 3)) and bacterial fatty acid markers (e.g., odd-numbered and/or branched; 18:1(n - 7)). Copepods in the SE contained low proportions of diatom (e.g., 16 : 4 (n - 1) ; 20 : 5 (n - 3)) and phytoplankton (e.g., polyunsaturated fatty acids) markers, relative to animals from northwest stations. Values of the omnivory index 'UC' (i.e., unsaturation coefficient) were also low in SE copepods, which implied reduced phytoplankton ingestion. Spatial patterns in seston fatty acid composition resembled the dietary signatures in that dinoflagellate and bacterial indices were highest in SE waters. Estimates of primary production, particulate organic carbon, carbon to chlorophyll ratios, and abundances of diatoms, dinoflagellates and bacteria, provided further evidence of the importance of the microbial loop at SE stations. Comparable spatial patterns in feeding strategy were observed in both sampling layers, indicating that copepods from the entire water column were feeding on a similar food source. Several interesting species-specific trends also emerged from the PCA. In general, C. hyperboreus fed the most herbivorously, followed by C. glacialis and M. longa. C. glacialis showed a stronger connection to the microbial food web than the other two species, and M. longa fed herbivorously throughout much of the polynya

  8. Distribution characteristics of volatile methylsiloxanes in Tokyo Bay watershed in Japan: Analysis of surface waters by purge and trap method.

    Science.gov (United States)

    Horii, Yuichi; Minomo, Kotaro; Ohtsuka, Nobutoshi; Motegi, Mamoru; Nojiri, Kiyoshi; Kannan, Kurunthachalam

    2017-05-15

    Surface waters including river water and effluent from sewage treatment plants (STPs) were collected from Tokyo Bay watershed, Japan, and analyzed for seven cyclic and linear volatile methylsiloxanes (VMSs), i.e., D3, D4, D5, D6, L3, L4, and L5 by an optimized purge and trap extraction method. The total concentrations of seven VMSs (ΣVMS) in river water ranged from <4.9 to 1700ng/L (mean: 220ng/L). The individual mean concentrations of cyclic VMSs in surface waters were; 10ng/L for D3, 13ng/L for D4, 180ng/L for D5, and 18ng/L for D6. The concentrations of ΣVMS determined in STP effluents varied widely from 99 to 2500ng/L and the individual mean concentrations were 21ng/L for D3, 27ng/L for D4, 540ng/L for D5, and 45ng/L for D6. D5, which is widely used in personal-care products, was found to be the most abundant compound in both river water and STP effluent. Linear VMSs were detected at much lower frequency and concentrations than those of cyclic VMSs. The measured concentrations of D4 were below the no-observed effect concentration (NOEC). The annual emission of ΣVMS through STPs into Tokyo Bay watershed was estimated at 2300kg. Our results indicate widespread distribution of VMSs in Tokyo Bay watershed and the influence of domestic wastewater discharges as a source of VMSs in the aquatic environment.

  9. Investigation of the spreading and dilution of domestic waste water inputs into a tidal bay using the finite-volume model FVCOM

    Science.gov (United States)

    Lettmann, Karsten; Wolff, Jörg-Olaf; Liebezeit, Gerd; Meier, Georg

    2010-05-01

    The 'Jade Bay' is a tidal bay located in the western part of the German Wadden Sea, southern North-Sea coast. During particularly heavy rain falls, rain water mixed with domestic waste water is discharged into the bay due to the limited capacities of the waste water treatment plant of the city of Wilhelmshaven. As the discharge point is located only a few hundred meters from a public bathing beach it is important to know spreading and dilution of the waste waters by tidal and wind-driven mixing. To model the behaviour of the waste water plumes, the unstructured mesh finite-volume model FVCOM (Chen and al., 2003) is used, which allows to cover the large area of the Jade and the nearby North Sea with a relatively high resolution near the point of discharge and a coarser resolution at the outer edges of the study side. We adapted the included sediment module of FVCOM to handle the sedimentation, decay and evolution in the bottom sediments of the discharged waste water particles, especially with respect to bacteria. Furthermore, alternative discharge points located in the interior of the Jade bay were tested, which might be more suited for a faster dilution and a smaller residence time of the waste water particles in the tidal bay.

  10. Using Hyperspectral Remote Sensing Models to Determine Phytoplankton Density in the Coastal Waters of Long Bay, South Carolina

    Science.gov (United States)

    Harrington, J. E.; Ali, K.

    2013-12-01

    The southeast coastal region is one of the fastest growing regions in the United States and the increasing utilization of open water bodies has led to the deterioration of water quality and aquatic ecology, placing the future of these resources at risk. In coastal zones, a key index that can be used to assess the stress on the environment is the water quality. The shallow nearshore waters of Long Bay, South Carolina (SC) are heavily influenced by multiple biogeochemical constituents or color producing agents (CPAs) such as, phytoplankton, suspend matter, and dissolved organic carbon. The interaction of the various chemical, biological and physical components gives rise to the optical complexity observed in the coastal waters producing turbid waters. Ecological stress on these environments is reflected by the increase in the frequency and severity of Harmful Algal Blooms (HABs), a prime agent of water quality deterioration, including foul odors and tastes, deoxygenation of bottom waters (hypoxia), toxicity, fish kills, and food web alterations. These are of great concern for human health and are detrimental to the marine life. Therefore, efficient monitoring tools are required for early detection and forecasting purposes as well as to understand the state of the conditions and better protect, manage and address the question of how various natural and anthropogenic factors affect the health of these environments. This study assesses the efficiency remote sensing as a potential tool for accurate and timely detection of HABs, as well as for providing high spatial and temporal resolution information regarding the biogeodynamics in coastal water bodies. Existing blue-green and NIR-red based remote sensing algorithms are applied to the reflectance data obtained using ASD spectroradiometer to predict the amount of chlorophyll, an independent of other associated CPAs in the Long Bay waters. The pigment is the primary light harvesting pigment in all phytoplankton and is used

  11. Biogeochemical study of water and bottom sediments from the Khai river - Nha Trang Bay estuarine system, South China Sea

    Science.gov (United States)

    Shulga, Natalia; Lobys, Nikolay; Drozdova, Anastasia; Peresypkin, Valery

    2014-05-01

    The present study was carried out in Nha Trang Bay (Southern Vietnam, the South China Sea). The samples of water, suspended matter and bottom sediments were collected in summer 2010-2012 in section from the estuary of the Khai River to the marine part of the bay. The samples were analyzed in the stationary lab of IO RAS, Moscow, by TOC-V-CPH, GC/MS and pirolysis methods. We report here the novel data on sources, transformation and burial of OM coming from the Khai river waters. The investigation is focused on ontent and distribution of suspended matter (SM) in the estuary, dissolved organic carbon (DOC), particulated organic carbon (POC); molecular and group composition of hydrocarbons (n-alkanes, steranes, hopanes) and mercury content in water, SM and bottom sediments. It was found that concentration of POC and SM decrease in the Nha Trang Bay waters from estuary to the open part of the bay. However, major changes in the concentration of SM and POC belong to the zone of salinity gradient.DOC behavior is more stable throughout the study area. Organic-geochemical indicators estimation allowed recognition of genesis and transformation degree of organic matter in the study area. The estuary is characterized by mixed genesis of SM with a predominance of allochthonous organic matter whereas outlying parts of the Nha Trang bay are characterized by autochthonous OM. Composition of OM in sediments reflects regularities identified above, despite of the interannual and seasonal variability in the study area. The investigation reveals a predominance of terrestrial organic matter in the silt sediments of the estuary, transported by the Khai river. Distribution of OM in sediments of marine part of the bay is mosaic, with a predominance of planktonogenic, bacterial or terrestrial input at their complex combination. Local anthropogenic pollution as well as an impact of industrial city effluents are found in river- and seaport areas. According to obtained data sedimentation rate

  12. PRIMARILY RESULTS OF PHYTOPLANKTON DNA AND VARIATION TO ENVIRONMENTAL FACTORS IN DURRES`S BAY COASTAL WATERS (ALBANIA

    Directory of Open Access Journals (Sweden)

    Laura Gjyli

    2013-10-01

    Full Text Available After isolation of phytoplankton DNA in coastal waters of Durres Bay, Albania, quantification and analysis of quality were investigated with spectrophotometric analysis. Analysis of UV absorption by the nucleotides provides a simple and accurate estimation of the concentration of nucleic acids in a sample. This method is however limited by the quantity of DNA and the purity of the preparation. Also biotic environment factors as Chlorophyll a and abiotic environment factors as temperature, salinity, pH, dissolved oxygen, turbidity, nitrate, phosphate were investigated to assess DNA quantities in different environment conditions. The Chlorophyll a was studied also to access the level of trophy. The sample stations were: Golem Beach (GB, Channel of Plepa (ChP, Hekurudha Beach (HB, Ex-Fuel Quay in Marine Durres Harbour (EFQ, Water Channel of Durres City (WChDC and Currila Beach (CB. Samples are taken in one meter depth from the water surface. Water samples were collected monthly from April to October 2011. The most abundant stations with phytoplankton DNA are Channel of Plepa and Water Channel of Durres City. This confirms that there are spills of fresh waters, sewage or agricultural water spills, often discharge in coastal waters. Referring Mutliple Regression Analysis and single regression analysis, the association between phytoplankton DNA and environment factors was strong (R2 = 0.75. Basing in single correlation and statistically significance (p-value ≤ 0.05, the enviroment factors that correlated to phytoplankton DNA were pH, salinity and phosphate; explaining thus the variation of total phytoplankton in Durres Bay coastal waters.

  13. Extensive Chaetoceros curvisetus bloom in relation to water quality in Port Blair Bay, Andaman Islands.

    Science.gov (United States)

    Begum, Mehmuna; Sahu, Biraja Kumar; Das, Apurba Kumar; Vinithkumar, Nambali Valsalan; Kirubagaran, Ramalingam

    2015-05-01

    Blooming of diatom species Chaetoceros curvisetus (Cleve, 1889) was observed in Junglighat Bay and Haddo Harbour of Port Blair Bay of Andaman and Nicobar Islands during June 2010. Physico-chemical parameters, nutrient concentrations and phytoplankton composition data collected from five stations during 2010 were classified as bloom area (BA) and non-bloom area (NBA) and compared. Elevated values of dissolved oxygen were recorded in the BA, and it significantly varied (p NBA. Among the nutrient parameters studied, nitrate concentration indicated significant variation in BA and NBA (p NBA, indicating its utilization. In Junglighat Bay, the C. curvisetus species constituted 93.4 and 69.2% composition of total phytoplankton population during day 1 and day 2, respectively. The bloom forming stations separated out from the non-bloom forming station in non-parametric multidimensional scaling (nMDS) ordinations; cluster analysis powered by SIMPROF test also grouped the stations as BA and NBA.

  14. Particle size distribution of suspended solids in the Chesapeake Bay entrance and adjacent shelf waters

    Science.gov (United States)

    Byrnes, M. R.; Oertel, G. F.

    1981-01-01

    Characteristics of suspended solids, including total suspended matter, total suspended inorganics, total suspended organics, particle size distribution, and the presence of the ten most prominent particle types were determined. Four research vessels simultaneously collected samples along four transects. Samples were collected within a 2-hour period that coincided with the maximum ebb penetration of Chesapeake Bay outwelling. The distribution of primary and secondary particle size modes indicate the presence of a surface or near-surface plume, possibly associated with three sources: (1) runoff, (2) resuspension of material within the Bay, and/or (3) resuspension of material in the area of shoals at the Bay mouth. Additional supportive evidence for this conclusion is illustrated with ocean color scanner data.

  15. Satellite Derived Water Quality Observations Are Related to River Discharge and Nitrogen Loads in Pensacola Bay, Florida

    Directory of Open Access Journals (Sweden)

    John C. Lehrter

    2017-09-01

    Full Text Available Relationships between satellite-derived water quality variables and river discharges, concentrations and loads of nutrients, organic carbon, and sediments were investigated over a 9-year period (2003–2011 in Pensacola Bay, Florida, USA. These analyses were conducted to better understand which river forcing factors were the primary drivers of estuarine variability in several water quality variables. Remote sensing reflectance time-series data were retrieved from the MEdium Resolution Imaging Spectrometer (MERIS and used to calculate monthly and annual estuarine time-series of chlorophyll a (Chla, colored dissolved organic matter (CDOM, and total suspended sediments (TSS. Monthly MERIS Chla varied from 2.0 mg m−3 in the lower region of the bay to 17.2 mg m−3 in the upper bay. MERIS CDOM and TSS exhibited similar patterns with ranges of 0.51–2.67 (m−1 and 0.11–8.9 (g m−3. Variations in the MERIS-derived monthly and annual Chla, CDOM, and TSS time-series were significantly related to monthly and annual river discharge and loads of nitrogen, organic carbon, and suspended sediments from the Escambia and Yellow rivers. Multiple regression models based on river loads (independent variables and MERIS Chla, CDOM, or TSS (dependent variables explained significant fractions of the variability (up to 62% at monthly and annual scales. The most significant independent variables in the regressions were river nitrogen loads, which were associated with increased MERIS Chla, CDOM, and TSS concentrations, and river suspended sediment loads, which were associated with decreased concentrations. In contrast, MERIS water quality variations were not significantly related to river total phosphorus loads. The spatially synoptic, nine-year satellite record expanded upon the spatial extent of past field studies to reveal previously unseen system-wide responses to river discharge and loading variation. The results indicated that variations in Pensacola Bay Chla

  16. NOAA Integrated Ocean and Coastal Mapping (IOCM) orthorectified mosaic true color (RGB) and infrared (IR) image tiles, Kachemak Bay, Alaska, 2008 (NODC Accession 0074379)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are a NOAA National Ocean Service National Geodetic Survey (NOS/NGS) Integrated Ocean and Coastal Mapping (IOCM) Product. The images were acquired from a...

  17. Notes on the Echinoderm Fauna of the Tapak Tuan Bay Waters, Aceh Selatan the Nangroe Aceh Darussalam

    Directory of Open Access Journals (Sweden)

    Eddy Yusron

    2003-12-01

    Full Text Available A total of 21 species of echinoderms, belonging to of 5 species Holothuroidea, 5 species of Asteroidea, 4 species Echinoidea and 7 species Ophiuroidea have been found in the Tapak Tuan of Aceh Selatan. The Ophiuroidea were relatively dominant in the sea grass zone. On the basis of population density, Ophiuroidea was the dominant group and relatively highest in the individual density. In general, the number of species of echinoderm fauna is smaller than that in the Sekotong Lombok Barat bay waters. The species composition, community structure, zonation, and spatial distribution of echinoderm fauna are discussed in this paper.

  18. Distributions and pollution assessment of heavy metals Pb, Cd and Cr in the water system of Kendari Bay, Indonesia

    Science.gov (United States)

    Armid, A.; Shinjo, R.; Ruslan, R.; Fahmiati

    2017-02-01

    The concentrations of heavy metals Pb, Cd and Cr in the coastal waters of Kendari Bay were analyzed to assess their pollution status. Water samples from 32 sampling points were analyzed for dissolved heavy metals concentrations by using inductively coupled plasma mass spectrometry (ICP-MS). The RSD(%) of each metal was accounted to analyze the diversity of the heavy metals among 32 sampling points. The results demonstrate that the dissolved heavy metal Pb had the highest concentrations (0.009 to 0.549 μg/L, average = 0.210 μg/L) followed by Cr (0.085 to 0.386 μg/L, average = 0.149 μg/L), and Cd (0.001 to 0.015 μg/L, average = 0.008 μg/L). Based on the the RSD values (Pb = 87.8%, Cd = 45.2% and Cr = 41.3%), it is suggested that the antropogenic activities controls the high diversity of concentrations for heavy metal Pb relative to those of Cd and Cr. Comparing the data with the mean oceanic concentrations, only the concentrations of Pb exceed the mean oceanic level (210 folds). Therefore, the water system of Kendari Bay is severely polluted with heavy metal Pb. More management and treatment should be introduced to protect the marine environment in the study area, especially from Pb pollution.

  19. 33 CFR 110.140 - Buzzards Bay, Nantucket Sound, and adjacent waters, Mass.

    Science.gov (United States)

    2010-07-01

    ... 154° from Palmer Island Light to Butler Flats Light; and north of a line bearing 267° from Butler Flats Light to the shore. (b) Buzzards Bay near entrance to approach channel to Cape Cod Canal—(1..., north of a line ranging 97°30′ from Cuttyhunk Light toward Nashawena Lighted Whistle Buoy to a point...

  20. EFFECTS OF HURRICANE IVAN ON WATER QUALITY IN PENSACOLA BAY, FL USA

    Science.gov (United States)

    Pensacola Bay was in the strong NE quadrant of Hurricane Ivan when it made landfall on September 16, 2004 as a category 3 hurricane on the Saffir-Simpson scale. We present data describing the timeline and maximum height of the storm surge, the extent of flooding of coastal land, ...

  1. 75 FR 13454 - Special Local Regulation, Fran Schnarr Open Water Championships, Huntington Bay, NY

    Science.gov (United States)

    2010-03-22

    ... Federal Register (73 FR 3316). Public Meeting We do not plan to hold a public meeting. But you may submit...-2009-0520) in the Federal Register (74 FR 51243). No comments or requests for meetings were received... Championships, Huntington Bay, NY AGENCY: Coast Guard, DHS. ACTION: Supplemental Notice of proposed...

  2. EFFECTS OF HURRICANE IVAN ON WATER QUALITY IN PENSACOLA BAY, FL USA

    Science.gov (United States)

    Pensacola Bay was in the strong NE quadrant of Hurricane Ivan when it made landfall on September 16, 2004 as a category 3 hurricane on the Saffir-Simpson scale. We present data describing the timeline and maximum height of the storm surge, the extent of flooding of coastal land, ...

  3. Seasonal variability of coastal water quality in bay of Bengal and Palk Strait, Tamilnadu, Southeast Coast of India

    Directory of Open Access Journals (Sweden)

    Viswanathan Srinivasan

    2013-10-01

    Full Text Available The aim of this work was to study the physicochemical parameters of water quality collected from 12 sampling stations from Topputhurai to Muthupet in Vedaranyam located on the southeast coast of India from January to December 2008. Results showed that the DO and nutrients were the maximum in the Bay of Bengal during the monsoon period. High concentration of the nutrients in summer season was obtained near the Muthupet mangroves compared to the Palk Strait, which showed that this acted as a source of nutrients to the adjacent coastal waters. Low concentrations of the nutrients observed in the monsoon could be attributed to the terrestrial runoff from Muthupet lagoon. The physicochemical characteristics of coastal waters between the Point Calimere and Muthupet could be used as a baseline data for the monitoring, conservation and management of Point Calimere Wildlife and Bird sanctuary, Great Vedaranyam swamp and Muthupet mangrove ecosystem.

  4. CASCO BAY PLAN

    Science.gov (United States)

    Casco Bay lies at the heart of Maine's most populated area. The health of its waters, wetlands, and wildlife depend in large part on the activities of the quarter-million residents who live in its watershed. Less than 30 years ago, portions of Casco Bay were off-limits to recr...

  5. Spatial and temporal trends in summertime climate and water quality indicators in the coastal embayments of Buzzards Bay, Massachusetts

    Science.gov (United States)

    Rheuban, J. E.; Williamson, S.; Costa, J. E.; Glover, D. M.; Jakuba, R. W.; McCorkle, D. C.; Neill, C.; Williams, T.; Doney, S. C.

    2016-01-01

    Degradation of coastal ecosystems by eutrophication is largely defined by nitrogen loading from land via surface water and groundwater flows. However, indicators of water quality are highly variable due to a myriad of other drivers, including temperature and precipitation. To evaluate these drivers, we examined spatial and temporal trends in a 22-year record of summer water quality data from 122 stations in 17 embayments within Buzzards Bay, MA (USA), collected through a citizen science monitoring program managed by Buzzards Bay Coalition. To identify spatial patterns across Buzzards Bay's embayments, we used a principle component and factor analysis and found that rotated factor loadings indicated little correlation between inorganic nutrients and organic matter or chlorophyll a (Chl a) concentration. Factor scores showed that embayment geomorphology in addition to nutrient loading was a strong driver of water quality, where embayments with surface water inputs showed larger biological impacts than embayments dominated by groundwater influx. A linear regression analysis of annual summertime water quality indicators over time revealed that from 1992 to 2013, most embayments (15 of 17) exhibited an increase in temperature (mean rate of 0.082 ± 0.025 (SD) °C yr-1) and Chl a (mean rate of 0.0171 ± 0.0088 log10 (Chl a; mg m-3) yr-1, equivalent to a 4.0 % increase per year). However, only seven embayments exhibited an increase in total nitrogen (TN) concentration (mean rate 0.32 ± 0.47 (SD) µM yr-1). Average summertime log10(TN) and log10(Chl a) were correlated with an indication that the yield of Chl a per unit total nitrogen increased with time suggesting the estuarine response to TN may have changed because of other stressors such as warming, altered precipitation patterns, or changing light levels. These findings affirm that nitrogen loading and physical aspects of embayments are essential in explaining the observed ecosystem response. However, climate

  6. North Inlet-Winyah Bay National Estuarine Research Reserve's (NERR) Estuarine Water Quality Data for the North Inlet and Winyah Bay Estuaries, Georgetown, South Carolina: 1993-2002

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — The North Inlet Estuary and the adjacent lower northeastern section of the Winyah Bay Estuary were designated as part of the National Estuarine Research Reserve...

  7. Assessment of estuarine water-quality indicators using MODIS medium-resolution bands: initial results from Tampa Bay, FL

    Science.gov (United States)

    Hu, Chuanmin; Chen, Zhiqiang; Clayton, Tonya D.; ,; Brock, John C.; Muller-Karger, Frank E.

    2004-01-01

    Using Tampa Bay, FL as an example, we explored the potential for using MODIS medium-resolution bands (250- and 500-m data at 469-, 555-, and 645-nm) for estuarine monitoring. Field surveys during 21–22 October 2003 showed that Tampa Bay has Case-II waters, in that for the salinity range of 24–32 psu, (a) chlorophyll concentration (11 to 23 mg m−3), (b) colored dissolved organic matter (CDOM) absorption coefficient at 400 nm (0.9 to 2.5 m−1), and (c) total suspended sediment concentration (TSS: 2 to 11 mg L−1) often do not co-vary. CDOM is the only constituent that showed a linear, inverse relationship with surface salinity, although the slope of the relationship changed with location within the bay. The MODIS medium-resolution bands, although designed for land use, are 4–5 times more sensitive than Landsat-7/ETM+ data and are comparable to or higher than those of CZCS. Several approaches were used to derive synoptic maps of water constituents from concurrent MODIS medium-resolution data. We found that application of various atmospheric-correction algorithms yielded no significant differences, due primarily to uncertainties in the sensor radiometric calibration and other sensor artifacts. However, where each scene could be groundtruthed, simple regressions between in situ observations of constituents and at-sensor radiances provided reasonable synoptic maps. We address the need for improvements of sensor calibration/characterization, atmospheric correction, and bio-optical algorithms to make operational and quantitative use of these medium-resolution bands.

  8. Cold-water coral ecosystems in the Penmarc’h and Guilvinec canyons (Bay of Biscay): deep-water versus shallow water settings

    Science.gov (United States)

    de Mol, L.; van Rooij, D.; Pirlet, H.; Quemmerais, F.; Greinert, J.; Frank, N.; Henriet, J.

    2009-12-01

    In 1948, Le Danois reported for the first time the occurrence of “massifs coralliens” along the European Atlantic continental margin. Within the framework of the EC FP6 IP HERMES and ESF EuroDIVERSITY MiCROSYSTEMS projects, the R/V Belgica BiSCOSYSTEMS cruise was set out to rediscover these cold-water corals in the Penmarc’h and Guilvinec canyons along the Gascogne margin of the Bay of Biscay. During this cruise, an area of 560 km2 was studied using swath bathymetry (EM1002), high-resolution reflection seismic profiling, CTD casts, ROV observations and USBL-guided boxcoring. Based on the multibeam data and the ROV video images, two different cold-water coral reef settings were distinguished. In water depths ranging from 260 to 350 m, mini-mounds up to 10 m high, covered by dead cold-water coral rubble, were observed. In between these mounds, an alternation of rippled and unrippled seabed with a patchy distribution of dropstones was observed. The second setting features both living and dead cold-water corals (predominantly Madrepora oculata) in water depths of 700 to 950 m. At certain locations, they form dense coral fields with a size of about 10-60 m, characterized by mostly dead corals and a few living ones. In this area also hard substrate with cracks, ridges, cliffs and oyster banks was noticed. Both the shallow area with the mini mounds (SE flank of the Guilvinec canyon) and the living and dead corals in the deeper setting were sampled with boxcores. These boxcores were used to determine the different sedimentary facies and to identify coral species present on the site. For this purpose, grain size analysis, U/Th dating of coral fragments, C14 datings of foraminifera and phylogenetic/genomic studies on living species were established. The cold-water corals from the deeper area occur in a density envelope (sigma-theta) of 27.3 - 27.4 kg.m-3, falling within the range of values which are considered to be a prerequisite for the development, growth and

  9. Preliminary estimates of residence times and apparent ages of ground water in the Chesapeake Bay watershed, and water-quality data from a survey of springs

    Science.gov (United States)

    Focazio, Michael J.; Plummer, L. Neil; Bohlke, John K.; Busenberg, Eurybiades; Bachman, L. Joseph; Powars, David S.

    1998-01-01

    Knowledge of the residence times of the ground-water systems in Chesapeake Bay watershed helps resource managers anticipate potential delays between implementation of land-management practices and any improve-ments in river and estuary water quality. This report presents preliminary estimates of ground-water residence times and apparent ages of water in the shallow aquifers of the Chesapeake Bay watershed. A simple reservoir model, published data, and analyses of spring water were used to estimate residence times and apparent ages of ground-water discharge. Ranges of aquifer hydraulic characteristics throughout the Bay watershed were derived from published literature and were used to estimate ground-water residence times on the basis of a simple reservoir model. Simple combinations of rock type and physiographic province were used to delineate hydrogeomorphic regions (HGMR?s) for the study area. The HGMR?s are used to facilitate organization and display of the data and analyses. Illustrations depicting the relation of aquifer characteristics and associated residence times as a continuum for each HGMR were developed. In this way, the natural variation of aquifer characteristics can be seen graphically by use of data from selected representative studies. Water samples collected in September and November 1996, from 46 springs throughout the watershed were analyzed for chlorofluorocarbons (CFC?s) to estimate the apparent age of ground water. For comparison purposes, apparent ages of water from springs were calculated assuming piston flow. Additi-onal data are given to estimate apparent ages assuming an exponential distribution of ages in spring discharge. Additionally, results from previous studies of CFC-dating of ground water from other springs and wells in the watershed were compiled. The CFC data, and the data on major ions, nutrients, and nitrogen isotopes in the water collected from the 46 springs are included in this report. The apparent ages of water

  10. Energy-water nexus analysis of enhanced water supply scenarios: a regional comparison of Tampa Bay, Florida, and San Diego, California.

    Science.gov (United States)

    Mo, Weiwei; Wang, Ranran; Zimmerman, Julie B

    2014-05-20

    Increased water demand and scarce freshwater resources have forced communities to seek nontraditional water sources. These challenges are exacerbated in coastal communities, where population growth rates and densities in the United States are the highest. To understand the current management dilemma between constrained surface and groundwater sources and potential new water sources, Tampa Bay, Florida (TB), and San Diego, California (SD), were studied through 2030 accounting for changes in population, water demand, and electricity grid mix. These locations were chosen on the basis of their similar populations, land areas, economies, and water consumption characters as well as their coastal locations and rising contradictions between water demand and supply. Three scenarios were evaluated for each study area: (1) maximization of traditional supplies; (2) maximization of seawater desalination; and (3) maximization of nonpotable water reclamation. Three types of impacts were assessed: embodied energy, greenhouse gas (GHG) emission, and energy cost. SD was found to have higher embodied energy and energy cost but lower GHG emission than TB in most of its water infrastructure systems because of the differences between the electricity grid mixes and water resources of the two regions. Maximizing water reclamation was found to be better than increasing either traditional supplies or seawater desalination in both regions in terms of the three impact categories. The results further imply the importance of assessing the energy-water nexus when pursuing demand-side control targets or goals as well to ensure that the potentially most economical options are considered.

  11. Galveston Bay

    Science.gov (United States)

    Handley, Lawrence R.; Spear, Kathryn A.; Eleonor Taylor,; Thatcher, Cindy

    2011-01-01

    The Galveston Bay estuary is located on the upper Texas Gulf coast (Lester and Gonzalez, 2002). It is composed of four major sub-bays—Galveston, Trinity, East, and West Bays. It is Texas’ largest estuary on the Gulf Coast with a total area of 155,399 hectares (384,000 acres) and 1,885 km (1,171 miles) of shoreline (Burgan and Engle, 2006). The volume of the bay has increased over the past 50 years due to subsidence, dredging, and sea level rise. Outside of ship channels, the maximum depth is only 3.7 m (12 ft), with the average depth ranging from 1.2 m (4 ft) to 2.4 m (8 ft)— even shallower in areas with widespread oyster reefs (Lester and Gonzalez, 2002). The tidal range is less than 0.9 m (3 ft), but water levels and circulation are highly influenced by wind. The estuary was formed in a drowned river delta, and its bayous were once channels of the Brazos and Trinity Rivers. Today, the watersheds surrounding the Trinity and San Jacinto Rivers, along with many other smaller bayous, feed into the bay. The entire Galveston Bay watershed is 85,470 km2 (33,000 miles2 ) large (Figure 1). Galveston Island, a 5,000 year old sand bar that lies at the western edge of the bay’s opening into the Gulf of Mexico, impedes the freshwater flow of the Trinity and San Jacinto Rivers into the Gulf, the majority of which comes from the Trinity. The Bolivar Peninsula lies at the eastern edge of the bay’s opening into the Gulf. Water flows into the Gulf at Bolivar Roads, 1 U.S. Geological Survey National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 2 Harte Research Institute for Gulf of Mexico Studies, Texas A&M University - Corpus Christi, 6300 Ocean Drive, Unit 5869, Corpus Christi, Texas 78412 2 Galveston Pass, between Galveston Island and Bolivar Peninsula, and at San Luis Pass, between the western side of Galveston Island and Follets Island.

  12. An evaluation of physical and biogeochemical processes regulating the oxygen minimum zone in the water column of the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sarma, V.V.S.S.

    waters of the Bay of Bengal (Figure 2). In this model, physical pump supplies oxygen through exchanges at the boundaries by physical processes such as upwelling, sinking, and water mass transport. The biological pump consumes oxygen by oxidation... consumption rate (81 Tg yr C01 ) computed in the present study. [21] The oxygen budget for the OMZ in the Bay of Bengal is depicted in Figure 8. Based on the budget calculations, about 81 Tg of oxygen is consumed in the OMZ annually. Out of this, about 0...

  13. Effect of the South Bay Ocean Outfall (SBOO) on ocean beach water quality near the USA-Mexico border.

    Science.gov (United States)

    Gersberg, Richard; Tiedge, Jürgen; Gottstein, Dana; Altmann, Sophie; Watanabe, Kayo; Lüderitz, Volker

    2008-04-01

    In early 1999, primary treatment and discharge of sewage from Tijuana, Mexico (approximately 95 million liters per day) began through South Bay Ocean Outfall (SBOO) into the ocean 4.3 km offshore. In this study, statistical comparisons were made of the bacterial water quality (total and fecal coliforms and enterococci densities) of the ocean, both before and after discharge of sewage to the SBOO began, so that the effect of this ocean discharge on nearshore ocean water quality could be quantitatively assessed. The frequency of exceedence of bacterial indicator thresholds was statistically analyzed for 11 shore (surfzone) stations throughout US and Mexico using the Fisher's exact test, for the years before (1995-1998) as compared to after the SBOO discharge began (1999-2003). Only four of the 11 shoreline stations (S2, S3, S11, and S12) showed significant improvement (decreased frequency of exceedence of bacterial indicator thresholds) after SBOO discharge began.

  14. Estimation of colored dissolved organic matter and salinity fields in case 2 waters using SeaWiFS: Examples from Florida Bay and Florida Shelf

    Indian Academy of Sciences (India)

    E J D'Sa; C Hu; F E Muller-Karger; K L Carder

    2002-09-01

    Estimates of water quality variables such as chlorophyll concentration (Chl), colored dissolved organic matter (CDOM), or salinity from satellite sensors are of great interest to resource managers monitoring coastal regions such as the Florida Bay and the Florida Shelf. However, accurate stimates of these variables using standard ocean color algorithms have been di#cult due to the complex nature of the light field in these environments. In this study, we process SeaWiFS satellite data using two recently developed algorithms; one for atmospheric correction and the other a semi-analytic bio-optical algorithm and compare the results with standard SeaWiFS algorithms. Overall, the two algorithms produced more realistic estimates of Chl and CDOM distributions in Florida Shelf and Bay waters. Estimates of surface salinity were obtained from the CDOM absorption field assuming a conservative mixing behavior of these waters. A comparison of SeaWiFS-derived Chl and CDOM absorption with field measurements in the Florida Bay indicated that although well correlated, CDOM was underestimated, while Chl was overestimated. Bottom reflectance appeared to affect these estimates at the shallow central Bay stations during the winter. These results demonstrate the need for new bio-optical algorithms or tuning of the parameters used in the bio-optical algorithm for local conditions encountered in the Bay.

  15. NASA-modified precipitation products to improve USEPA nonpoint source water quality modeling for the Chesapeake Bay.

    Science.gov (United States)

    Nigro, Joseph; Toll, David; Partington, Ed; Ni-Meister, Wenge; Lee, Shihyan; Gutierrez-Magness, Angelica; Engman, Ted; Arsenault, Kristi

    2010-01-01

    The USEPA has estimated that over 20,000 water bodies within the United States do not meet water quality standards. One of the regulations in the Clean Water Act of 1972 requires states to monitor the total maximum daily load, or the amount of pollution that can be carried by a water body before it is determined to be "polluted," for any watershed in the United States (Copeland, 2005). In response to this mandate, the USEPA developed Better Assessment Science Integrating Nonpoint Sources (BASINS) as a decision support tool for assessing pollution and to guide the decision-making process for improving water quality. One of the models in BASINS, the Hydrological Simulation Program-Fortran (HSPF), computes continuous streamflow rates and pollutant concentration at each basin outlet. By design, precipitation and other meteorological data from weather stations serve as standard model input. In practice, these stations may be unable to capture the spatial heterogeneity of precipitation events, especially if they are few and far between. An attempt was made to resolve this issue by substituting station data with NASA-modified/NOAA precipitation data. Using these data within HSPF, streamflow was calculated for seven watersheds in the Chesapeake Bay Basin during low flow periods, convective storm periods, and annual flows. In almost every case, the modeling performance of HSPF increased when using the NASA-modified precipitation data, resulting in better streamflow statistics and, potentially, in improved water quality assessment.

  16. Comparison of Discrete-return ranging and Full-waveform digitization for Bathymetric Lidar Mapping of a Shallow Water Bay

    Science.gov (United States)

    Starek, M. J.; Fernandez-diaz, J.; Pan, Z.; Glennie, C. L.; Shrestha, R. L.; Gibeaut, J. C.; Singhania, A.

    2013-12-01

    Researchers with the National Center for Airborne Laser Mapping (NCALM) at the University of Houston (UH) and the Coastal and Marine Geospatial Sciences Lab (CMGL) of the Harte Research Institute at Texas A&M University-Corpus Christi conducted a coordinated airborne and field-based survey of the Redfish Bay State Scientific Area to investigate the capabilities of shallow water bathymetric lidar for benthic mapping. Redfish Bay, located along the middle Texas coast of the Gulf of Mexico, is a state scientific area designated for the purposes of protecting and studying the native seagrasses. The mapped region is very shallow (truth data of benthic type at over 80 locations within the bay. The return signal of an Aquarius lidar pulse is analyzed in real time by a hardware-based constant fraction discriminator (CFD) to detect returns from the surface and determine ranges (x,y,z points). This approach is commonly called discrete-return ranging, and Aquarius can record up to 4 returns per an emitted laser pulse. In contrast, full-waveform digitization records the incoming energy of an emitted pulse by sampling it at very high-frequency. Post-processing algorithms can then be applied to detect returns (ranges) from the digitized waveform. For this survey, a waveform digitizer was simultaneously operated to record the return waveforms at a rate of 1GHz with 12 bit dynamic range. High-resolution digital elevation models (DEMs) of the topo-bathymetry were derived from the discrete-return and full-waveform data to evaluate the relative and absolute accuracy using the collected ground-truth data. Results of this evaluation will be presented including an overview of the method used to extract peaks from the waveform data. Potential advantages and disadvantages of the different ranging modes in terms of observed accuracy, increased processing load, and information gain will also be discussed.

  17. Evaluation of effects of changes in canal management and precipitation patterns on salinity in Biscayne Bay, Florida, using an integrated surface-water/groundwater model

    Science.gov (United States)

    Lohmann, Melinda A.; Swain, Eric D.; Wang, John D.; Dixon, Joann

    2012-01-01

    Biscayne National Park, located in Biscayne Bay in southeast Florida, is one of the largest marine parks in the country and sustains a large natural marine fishery where numerous threatened and endangered species reproduce. In recent years, the bay has experienced hypersaline conditions (salinity greater than 35 practical salinity units) of increasing magnitude and duration. Hypersalinity events were particularly pronounced during April to August 2004 in nearshore areas along the southern and middle parts of the bay. Prolonged hypersaline conditions can cause degradation of water quality and permanent damage to, or loss of, brackish nursery habitats for multiple species of fish and crustaceans as well as damage to certain types of seagrasses that are not tolerant of extreme changes in salinity. To evaluate the factors that contribute to hypersalinity events and to test the effects of possible changes in precipitation patterns and canal flows into Biscayne Bay on salinity in the bay, the U.S. Geological Survey constructed a coupled surface-water/groundwater numerical flow model. The model is designed to account for freshwater flows into Biscayne Bay through the canal system, leakage of salty bay water into the underlying Biscayne aquifer, discharge of fresh and salty groundwater from the Biscayne aquifer into the bay, direct effects of precipitation on bay salinity, indirect effects of precipitation on recharge to the Biscayne aquifer, direct effects of evapotranspiration (ET) on bay salinity, indirect effects of ET on recharge to the Biscayne aquifer, and maintenance of mass balance of both water and solute. The model was constructed using the Flow and Transport in a Linked Overland/Aquifer Density Dependent System (FTLOADDS) simulator, version 3.3, which couples the two-dimensional, surface-water flow and solute-transport simulator SWIFT2D with the density-dependent, groundwater flow an solute-transport simulator SEAWAT. The model was calibrated by a trial

  18. Chemical and histological comparisons between Brevoortia sp. (menhaden) collected in fall 2010 from Barataria Bay, LA and Delaware Bay, NJ following the DeepWater Horizon (DWH) oil spill.

    Science.gov (United States)

    Bentivegna, Carolyn S; Cooper, Keith R; Olson, Gregory; Pena, Edwin A; Millemann, Daniel R; Portier, Ralph J

    2015-12-01

    Body burdens of PAHs were compared to histological effects in menhaden (Family: Clupeidae, Genus: Brevoortia) collected in fall 2010 from Barataria Bay, LA (BBLA) and Delaware Bay, NJ (DBNJ). Barataria Bay was heavily oiled during the DeepWater Horizon (DWH) oil spill, while Delaware Bay although urbanized had no reported recent oil spills. GCMS analyses of pre-spill 2009, BBLA and DBNJ fish found predominantly C2/C3 phenanthrene (1.28-6.52 ng/mg). However, BBLA also contained five higher molecular weight PAHs (0.06-0.34 ng/mg DW). Fluorescent aromatic compound spectroscopy (FACS) of gastrointestinal (GI) tract tissue showed statistically higher levels of hydroxypyrene-like PAHs in DBNJ than BBLA fish. Histopathologic lesions were more prevalent in BBLA than DBNJ fish. The lesion prevalence (gill, trunk kidney, epidermis, stomach) in the BBLA menhaden were significantly higher and more severe than observed in the DBNJ menhaden. Reversible lesions included gill lamellar hyperplasia, adhesions, edema, and epidermal hyperplasia. The increased pigmented macrophage centers were indicative of activated macrophages responding to connective tissue damage or other antigens. The liver hepatic necrosis and renal tissue mineralization may well have undergone repair, but damage to the kidney nephrons and hepatic/biliary regions of the liver would be slower to resolve and apparently remained after elimination of PAHs. Therefore, a direct cause and effect between DWH oil spill and increased lesion prevalence in BBLA menhaden could not be established.

  19. Partitioning behavior of per- and polyfluoroalkyl compounds between pore water and sediment in two sediment cores from Tokyo Bay, Japan.

    Science.gov (United States)

    Ahrens, Lutz; Yamashita, Nobuyoshi; Yeung, Leo W Y; Taniyasu, Sachi; Horii, Yuichi; Lam, Paul K S; Ebinghaus, Ralf

    2009-09-15

    The partitioning behavior of per- and polyfluoroalkyl compounds (PFCs) between pore water and sediment in two sediment cores collected from Tokyo Bay, Japan, was investigated. In addition, the fluxes and temporal trends in one dated sediment core were studied. Short-chain perfluoroalkyl carboxylic acids (PFCAs) (C or = 11) were found only in sediment The perfluoroalkyl sulfonates (PFSAs), n-ethylperfluoro-1-octanesulfonamidoacetic acid (N-EtFOSAA), and perfluorooctane sulfonamide (PFOSA) seemed to bind more strongly to sediment than PFCAs. The enrichment of PFCs on sediment increased with increasing organic matter and decreasing pH. The perfluorocarbon chain length and functional group were identified as the dominating parameters that had an influence on the partitioning behavior of the PFCs in sediment The maximum SigmaPFC contamination in sediment was observed in 2001-2002 to be a flux of 197 pg cm(-2) yr(-1). Statistically significant increased concentrations in Tokyo Bay were found for perfluorooctanesulfonate (PFOS) (1956-2008), perfluorononanoic acid (PFNA) (1990-2008), and perfluoroundecanoic acid (PFUnDA) (1990-2008). Concentrations of PFOSA and N-EtFOSAA increased between 1985 and 2001, but after 2001, the concentration decreased significantly, which corresponded with the phase out of perfluorooctyl sulfonyl fluoride-based compounds by the 3M Company in 2000.

  20. Occurrence of herbicides and pharmaceutical and personal care products in surface water and groundwater around Liberty Bay, Puget Sound, Washington

    Science.gov (United States)

    Dougherty, Jennifer A.; Swarzenski, Peter W.; Dinicola, Richard S.; Reinhard, Martin

    2010-01-01

    Organic contaminants, such as pharmaceuticals and personal care products (PPCPs), pose a risk to water quality and the health of ecosystems. This study was designed to determine if a coastal community lacking point sources, such as waste water treatment plant effluent, could release PPCPs, herbicides, and plasticizers at detectable levels to their surface water and groundwater. Research was conducted in Liberty Bay, an embayment within Puget Sound, where 70% of the population (∼10,000) uses septic systems. Sampling included collection of groundwater and surface water with grab samples and the use of polar organic chemical integrative samplers (POCIS). We analyzed for a broad spectrum of 25 commonly used compounds, including PPCPs, herbicides, and a flame retardant. Twelve contaminants were detected at least once; only N,N-diethyl-meta-toluamide, caffeine, and mecoprop, a herbicide not attributed to septic systems, were detected in more than one grab sample. The use of POCIS was essential because contaminants were present at very low levels (nanograms), which is common for PPCPs in general, but particularly so in such a small community. The use of POCIS allowed the detection of five compounds that were not present in grab samples. Data suggest that the community is contaminating local water with PPCPs; this effect is likely to increase as the population and product usage increase. The results presented here are a first step toward assessing the transport of herbicides and PPCPs into this coastal system.

  1. Identification and Determination of Microcystins in Source Water an Waterbloom Sample From Meiliang Bay, Taihu Lake, China

    Institute of Scientific and Technical Information of China (English)

    XIAO-GANG FENG; ZHEN DING; TAO WEI; CHUN-WEI YUAN; DE-GANG FU

    2006-01-01

    Objective To identify and determine the congener and level of microcystins in the source water of Taihu Lake. Methods Improved method of SPE combined with HPLC was employed to detect the concentration and varieties of microcystins in source water and bloom samples collected from Meiliang Bay, Taihu Lake. Results The contents of two predominant microcystin components, MC-RR, and MC-LR, were relatively high in samples during warm months and correlated with the phase of algae growth. The maximum concentrations of MC-RR and MC-LR in water sample reached 3.09 ±0.53 μg/L and 2.39±0.41 μg/L during the period of water bloom in September 2004, respectively. Even without waterbloom, the concentration of MC-LR in source water sample was still higher than the guideline value. Conclusion The status of microcystin pollution in this region is serious and measures to monitor and control the growth of cyanobacteria are urgently needed.

  2. Impact of Shrimp Farm Effluent on Water Quality in Coastal Areas of the World Heritage-Listed Ha Long Bay

    Directory of Open Access Journals (Sweden)

    Thuyet D. Bui

    2012-01-01

    Full Text Available Problem statement: Shrimp farming has rapidly developed in coastal areas of the World Heritage-listed Ha Long Bay since the last decade. Effluent discharged from shrimp farms with high levels of nutrient waste may cause eutrophication in receiving waterways. Therefore, assessing water quality at tidal creeks receiving shrimp farm effluent in coastal areas of Ha Long Bay supports environmental protection and decision making for sustainable development of the region. Approach: Water samples were collected at 3 different locations for spatial assessment: inside sections of creeks directly receiving farm effluent (IEC, from main creeks adjacent to points of effluent discharge outside concentrated shrimp farms (OEC and a few kilometers away from shrimp farm (ASF. Samples were taken on 3 occasions for temporal assessment. Parameters related to nutrient waste from shrimp farms, including: Total Ammonia Nitrogen (TAN, Nitrite-Nitrogen (NO2-N, Nitrate-Nitrogen (NO3-N, Total Phosphorus (TP, Dissolved Orthophosphate (PO4-P, Biochemical Oxygen Demand (BOD, Chemical Oxygen Demand (COD, Total Suspended Solid (TSS, Chlorophyll-a (Chl-a, Temperature, Salinity, pH and Dissolved Oxygen (DO were determined using standard methods. Results: There were statistically significant differences in the concentrations of TAN, NO2-N, NO3-N, TP, PO4-P, BOD, COD and Chl-a among IEC, OEC, ASF and the levels of these parameters increased after shrimp crops, especially after the main shrimp crop of the season in North Vietnam. The concentrations of TAN, NO3-N, TP, BOD, COD, Chl-a, TSS at IEC sites were higher than recommended for protecting aquatic ecosystems. Principal Component Analysis (PCA efficiently summarized patterns of co-variation in water quality parameters among locations and study times. Conclusion/Recommendations: The findings of this study indicate that greater awareness of the environmental impacts of shrimp farms is required if this industry is to be sustainable

  3. Sculpted by water, elevated by earthquakes—The coastal landscape of Glacier Bay National Park, Alaska

    Science.gov (United States)

    Witter, Robert C.; LeWinter, Adam; Bender, Adrian M.; Glennie, Craig; Finnegan, David

    2017-05-22

    Within Glacier Bay National Park in southeastern Alaska, the Fairweather Fault represents the onshore boundary between two of Earth’s constantly moving tectonic plates: the North American Plate and the Yakutat microplate. Satellite measurements indicate that during the past few decades the Yakutat microplate has moved northwest at a rate of nearly 5 centimeters per year relative to the North American Plate. Motion between the tectonic plates results in earthquakes on the Fairweather Fault during time intervals spanning one or more centuries. For example, in 1958, a 260-kilometer section of the Fairweather Fault ruptured during a magnitude 7.8 earthquake, causing permanent horizontal (as much as 6.5 meters) and vertical (as much as 1 meter) displacement of the ground surface across the fault. Thousands to millions of years of tectonic plate motion, including earthquakes like the one in 1958, raised and shifted the ground surface across the Fairweather Fault, while rivers, glaciers, and ocean waves eroded and sculpted the surrounding landscape along the Gulf of Alaska coast in Glacier Bay National Park.

  4. Evaluation of surface water and sediment quality in Chicalim Bay, Nerul Creek, and Chapora Bay from Goa coast, India - a statistical approach

    Digital Repository Service at National Institute of Oceanography (India)

    Shenai-Tirodkar, P.S.; Gauns, M.U.; Ansari, Z.A.

    ores transportations. Nerul Creek (NC) (15°30’37.70” N, 73°46’48.75”E) opens into the Aguada Bay of Mandovi estuary and extends inside the land in U-shape up to a length of about ~8.5 km. This site is influenced by restaurants discharge, fishing...

  5. Foraminifera and paleoenvironment of the Plio-Pleistocene Kallithea Bay section, Rhodes, Greece: Evidence for cyclic sedimentation and shallow-water sapropels

    DEFF Research Database (Denmark)

    Rasmussen, Tine Lander; Thomsen, Erik

    2005-01-01

    Nearly 250 species of benthic foraminifera have been identified from the Plio-Pleistocene strata of the Kallithea Bay section on the eastern coast of Rhodes. The section comprises an overall transgressive succession ranging from fluviatile and brackish-water gravel at the base to fine-grained dee...

  6. Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,2008.The hydrodynamic parameters and water quality parameters(e.g.flow velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 m.The water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different directions.The water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding process.Meanwhile,the water stability index in the mainstream remained small but it was lowered in the XXB.The main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding process.The grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the process.However,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.

  7. Water quality measurements in San Francisco Bay by the U.S. Geological Survey, 1969-2015.

    Science.gov (United States)

    Schraga, Tara S; Cloern, James E

    2017-08-08

    The U.S. Geological Survey (USGS) maintains a place-based research program in San Francisco Bay (USA) that began in 1969 and continues, providing one of the longest records of water-quality measurements in a North American estuary. Constituents include salinity, temperature, light extinction coefficient, and concentrations of chlorophyll-a, dissolved oxygen, suspended particulate matter, nitrate, nitrite, ammonium, silicate, and phosphate. We describe the sampling program, analytical methods, structure of the data record, and how to access all measurements made from 1969 through 2015. We provide a summary of how these data have been used by USGS and other researchers to deepen understanding of how estuaries are structured and function differently from the river and ocean ecosystems they bridge.

  8. Water quality measurements in San Francisco Bay by the U.S. Geological Survey, 1969–2015

    Science.gov (United States)

    Schraga, Tara; Cloern, James E.

    2017-01-01

    The U.S. Geological Survey (USGS) maintains a place-based research program in San Francisco Bay (USA) that began in 1969 and continues, providing one of the longest records of water-quality measurements in a North American estuary. Constituents include salinity, temperature, light extinction coefficient, and concentrations of chlorophyll-a, dissolved oxygen, suspended particulate matter, nitrate, nitrite, ammonium, silicate, and phosphate. We describe the sampling program, analytical methods, structure of the data record, and how to access all measurements made from 1969 through 2015. We provide a summary of how these data have been used by USGS and other researchers to deepen understanding of how estuaries are structured and function differently from the river and ocean ecosystems they bridge.

  9. Physico-chemical characterization of surface waters of the west coast of Algeria: Bay of Mostaganem and Cheliff estuary

    Directory of Open Access Journals (Sweden)

    Fatima Kies

    2014-12-01

    Full Text Available A follow-up in 2013 of the indicators of pollution (temperature, hydrogen potential, salinity, dissolved oxygen, ammonium, nitrites, nitrates, orthophosphates, ortho silicates, biological oxygen demand, chemical oxygen demand, suspended solids in surface water was performed, in order to estimate the physicochemical quality of the west coast of Algeria. The results obtained revealed the existence of a water contamination by domestic and industrial waste water conveyed to the north by the Cheliff River for discharge into the Bay of Mostaganem, marked by significant space-time variations. In January (24 mg / l, the values of nitrates recorded west of the mouth of Cheliff exceed norms. Ammonium records strong concentrations in January (1.2 mg NH4+/ l and in February (0.8 mg /l. Nitrites such lagging of high contents in January (NO2- 0.99 mg / l and February (NO2- 0.59 mg /l, respectively. The ortho phosphates post a maximum concentration in January (6.6mg PO43-/ l. In addition, the organic matter rate measured in surface water is maximum during periods of flooding especially in January (7.51 mg / l and lowest in the exceptionally dry season in August (2.19 mg / l.

  10. Seasonal distribution and abundance of cetaceans within French waters- Part II: The Bay of Biscay and the English Channel

    Science.gov (United States)

    Laran, Sophie; Authier, Matthieu; Blanck, Aurélie; Doremus, Ghislain; Falchetto, Hélène; Monestiez, Pascal; Pettex, Emeline; Stephan, Eric; Van Canneyt, Olivier; Ridoux, Vincent

    2017-07-01

    From the Habitat Directive to the recent Marine Strategy Framework Directive, the conservation status of cetaceans in European water has been of concern for over two decades. In this study, a seasonal comparison of the abundance and distribution of cetaceans was carried out in two contrasted regions of the Eastern North Atlantic, the Bay of Biscay and the English Channel. Estimates were obtained in the two sub-regions (375,000 km²) from large aerial surveys conducted in the winter (November 2011 to February 2012) and in the summer (May to August 2012). The most abundant species encountered in the Channel, the harbour porpoise, displayed strong seasonal variations in its distribution but a stable abundance (18,000 individuals, CV=30%). In the Bay of Biscay, abundance and distribution patterns of common / striped dolphins varied from 285,000 individuals (95% CI: 174,000-481,000) in the winter, preferentially distributed close to the shelf break, to 494,000 individuals (95% CI: 342,000-719,000) distributed beyond the shelf break in summer. Baleen whales also exhibited an increase of their density in summer. Seasonal abundances of bottlenose dolphins were quite stable, with a large number of 'pelagic' encounters offshore in winter. No significant seasonal difference was estimated for pilot whales and sperm whale. These surveys provided baseline estimates to inform policies to be developed, or for existing conservation instruments such as the Habitats Directive. In addition, our results supported the hypothesis of a shift in the summer distributions of some species such as harbour porpoise and minke whale in European waters.

  11. Numerical Simulation of Water Exchange Characteristics of the Jiaozhou Bay Based on A Three-Dimensional Lagrangian Model

    Institute of Scientific and Technical Information of China (English)

    WANG Cui; ZHANG Xue-qing; SUN Ying-lan

    2009-01-01

    Based on theory of three-dimensional hydrodynamics,an Euler-Lagrangian particle model is established to study the transport and water exchange capability in the Jiaozhou Bay.The three-dimensional hydrodynamic model,driven by tide and wind,is used to study the effects of wetting and drying of eatuarine intertidal flats by the dry-wet grid technology based on the Estuarine,Coastal and Ocean Model (ECOM).The particle model includes the advection and the diffusion processes,of which the advection process is simulated with a certain method,and the diffusion process is simulated with the random walk method.The effect of the intertidal zone,the turbulent diffusion and the timescales of the water exchange are also discussed.The results show that a moving boundary model can simulate the transport process of the particle in the intertidal zone,where the particles are transported for a longer distance than that of the stationary result.Simulations with and without the turbulent random walk show that the effect of turbulent diffusion is very effective at spreading particles throughout the estuary and speeding up the particle movement.The spatial distribution of residence time is given to quantify the water exchange capability that has very important ramifications to water quality.The effect of wind on the water exchange is also examined and the southeasterly wind in summer tends to block the water exchange near the northeast coast,while the northerly wind in winter speeds up the transport process.These results indicate that the Lagrangian particle model is applicable and has a large potential to help understanding the water exchange capability in estuaries,which can also he useful to simulate the transport process of contaminant.

  12. Pore-water chemistry from the ICDP-USGS coer hole in the Chesapeake Bay impact structure--Implications for paleohydrology, microbial habitat, and water resources

    Science.gov (United States)

    Sanford, Ward E.; Voytek, Mary A.; Powars, David S.; Jones, Blair F.; Cozzarelli, Isabelle M.; Eganhouse, Robert P.; Cockell, Charles S.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between fresh and saline water from 100 to 500 m depth in the post-impact sediment section, and an underlying syn-impact section that is almost entirely filled with brine. The presence of brine in the lowermost post-impact section and the trend in the dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting its occurrence may be common in the inner crater. However, groundwater flow conditions in the structure may reduce the salt-water-intrusion hazard associated with the brine.

  13. NASA-Modified Precipitation Products to Improve EPA Nonpoint Source Water Quality Modeling for the Chesapeake Bay

    Science.gov (United States)

    Nigro, Joseph; Toll, David; Partington, Ed; Ni-Meister, Wenge; Lee, Shihyan; Gutierrez-Magness, Angelica; Engman, Ted; Arsenault, Kristi

    2010-01-01

    The Environmental Protection Agency (EPA) has estimated that over 20,000 water bodies within the United States do not meet water quality standards. Ninety percent of the impairments are typically caused by nonpoint sources. One of the regulations in the Clean Water Act of 1972 requires States to monitor the Total Maximum Daily Load (TMDL), or the amount of pollution that can be carried by a water body before it is determined to be "polluted", for any watershed in the U.S.. In response to this mandate, the EPA developed Better Assessment Science Integrating Nonpoint Sources (BASINS) as a Decision Support Tool (DST) for assessing pollution and to guide the decision making process for improving water quality. One of the models in BASINS, the Hydrological Simulation Program -- Fortran (HSPF), computes daily stream flow rates and pollutant concentration at each basin outlet. By design, precipitation and other meteorological data from weather stations serve as standard model input. In practice, these stations may be unable to capture the spatial heterogeneity of precipitation events especially if they are few and far between. An attempt was made to resolve this issue by substituting station data with NASA modified/NOAA precipitation data. Using these data within HSPF, stream flow was calculated for seven watersheds in the Chesapeake Bay Basin during low flow periods, convective storm periods, and annual flows. In almost every case, the modeling performance of HSPF increased when using the NASA-modified precipitation data, resulting in better stream flow statistics and, ultimately, in improved water quality assessment.

  14. 75 FR 36292 - Safety Zone; Bay Swim III, Presque Isle Bay, Erie, PA

    Science.gov (United States)

    2010-06-25

    ... of Presque Isle Bay, Lake Erie, near Erie, Pennsylvania between 9 a.m. to 11 a.m. on June 26, 2010.... The safety zone will encompass specified waters of Presque Isle Bay, Erie, Pennsylvania starting at... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Bay Swim III, Presque Isle Bay, Erie, PA...

  15. Pore-water chemistry from the ICDP-USGS core hole in the Chesapeake Bay impact structure-Implications for paleohydrology, microbial habitat, and water resources

    Science.gov (United States)

    Sanford, W.E.; Voytek, M.A.; Powars, D.S.; Jones, B.F.; Cozzarelli, I.M.; Cockell, C.S.; Eganhouse, R.P.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between freshwater and saline water from 100 to 500 m depth in the postimpact sediment section, and an underlying synimpact section that is almost entirely filled with brine. The presence of brine in the lowermost postimpact section and the trend in dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting that its occurrence may be common in the inner crater. However, groundwater-flow conditions in the structure may reduce the saltwater-intrusion hazard associated with the brine. ?? 2009 The Geological Society of America.

  16. 33 CFR 117.622 - West Bay

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false West Bay 117.622 Section 117.622 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Massachusetts § 117.622 West Bay The draw of the West Bay Bridge, mile...

  17. [Pollution by heavy metals in the petrochemical sewage waters of the sea area of Daya Bay and assessment on potential ecological risks].

    Science.gov (United States)

    Xu, Shan-Nan; Li, Chun-Hou; Xu, Jiao-Jiao; Xiao, Ya-Yuan; Lin, Lin; Huang, Xiao-Ping

    2014-06-01

    This study aimed to gain a clear understanding on the status of pollution by heavy metals in the petrochemical sewage and the potential ecological risk caused by heavy metal pollution in the sea area of Daya Bay. The contents and spatial distributions of heavy metals including Zn, Pb, Cu, Cd, Cr, As and Hg in seawater, sediment and fishes collected from Daya Bay were analyzed. The comprehensive pollution index (CPI) and ecological risk indexes (ERIs) were used to evaluate the contaminated severity and potential ecological risks of heavy metals in seawater and sediment. The results showed that the contents of these heavy metals, except for those of Zn and Pb, in several stations set in Daya Bay from 2011 to 2012 were relatively low, which were lower than the quality standard of class I according to the China National Standard Criteria for Seawater Quality, suggesting that the seawater in Daya Bay has not been polluted yet by these heavy metals. The average CPI of heavy metals in seawater during flooding season (0.72) was higher than that during dry season (0.38) whereas the average CPI of heavy metals in sediment during dry season (7.77) was higher than that during flooding season (5.70). Hg was found to be the primary contaminating heavy metal in sediment during dry season, which was followed by As and Zn whereas during flooding season, Hg was the primary contaminating metal in sediment, followed by Zn and Cu. The contents of these 7 heavy metals in fishes collected from the surveyed areas were lower than those of the standard requirements. A correlation analysis indicated that there were significant differences in the correlations between the midst of the heavy metals in sea water and the different periods. The ERIs of heavy metals in sediment during dry season (129.20) was higher than that during flooding season (102.86), and 25% of the sampling sites among all stations were under the risk of high-level alarm. The potential ERIs of heavy metals in sediment in

  18. Ground-Water Quality Data in the San Francisco Bay Study Unit, 2007: Results from the California GAMA Program

    Science.gov (United States)

    Ray, Mary C.; Kulongoski, Justin T.; Belitz, Kenneth

    2009-01-01

    Ground-water quality in the approximately 620-square-mile San Francisco Bay study unit (SFBAY) was investigated from April through June 2007 as part of the Priority Basin project of the Ground-Water Ambient Monitoring and Assessment (GAMA) Program. The GAMA Priority Basin project was developed in response to the Groundwater Quality Monitoring Act of 2001, and is being conducted by the U.S. Geological Survey (USGS) in cooperation with the California State Water Resources Control Board (SWRCB). The study was designed to provide a spatially unbiased assessment of raw ground-water quality, as well as a statistically consistent basis for comparing water quality throughout California. Samples in SFBAY were collected from 79 wells in San Francisco, San Mateo, Santa Clara, Alameda, and Contra Costa Counties. Forty-three of the wells sampled were selected using a spatially distributed, randomized grid-based method to provide statistical representation of the study unit (grid wells). Thirty-six wells were sampled to aid in evaluation of specific water-quality issues (understanding wells). The ground-water samples were analyzed for a large number of synthetic organic constituents (volatile organic compounds [VOC], pesticides and pesticide degradates, pharmaceutical compounds, and potential wastewater-indicator compounds), constituents of special interest (perchlorate and N-nitrosodimethylamine [NDMA]), naturally occurring inorganic constituents (nutrients, major and minor ions, trace elements, chloride and bromide isotopes, and uranium and strontium isotopes), radioactive constituents, and microbial indicators. Naturally occurring isotopes (tritium, carbon-14 isotopes, and stable isotopes of hydrogen, oxygen, nitrogen, boron, and carbon), and dissolved noble gases (noble gases were analyzed in collaboration with Lawrence Livermore National Laboratory) also were measured to help identify the source and age of the sampled ground water. Quality-control samples (blank samples

  19. Reproductive traits of sandbird octopus, Amphioctopus aegina (Gray, 1849) from Mandapam coastal waters (Palk Bay), Southeast Coast of India

    Science.gov (United States)

    Ignatius, Boby; Srinivasan, Muthukumarasamy; Balakrishnan, Srinivasan

    2011-09-01

    The sandbird octopus Amphioctopus aegina (Gray, 1849) is one of the important octopod species in trawl catches in Mandapam waters (Palk Bay). The reproductive biology of this species from these waters was studied from October 2001 to September 2002. In the majority of months(Jan-June), the sex ratio was biased towards males. The ratios of males to females increased consistently with respect to weight Total weight at first maturity were 78.78g for females and 40.8 g for males. Four maturity stags were recognized for females and two for males. Maturation and spawning occur all year round, with a peak during October and another peak during January-February. In males, no definite seasonal changes were observed in gonadosomatic index (GSI) values. In females there were two peaks in GSI values during October and January-February. For individuals of a DML range of 67-85 mm fecundity varied between 2,962-8,820 oocytes. The average relative fecundity was estimated at 68 to 83 and the average number oocytes per gram of ovary were 488 to 539.

  20. FREQUENT MONITORING OF WATER TEMPERATURE IN PEGAMETAN BAY, BALI: A PRELIMINARY ASSESSMENT TOWARDS MANAGEMENT OF MARINE AQUACULTURE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    I Nyoman Radiarta

    2014-12-01

    Full Text Available Aquaculture currently share for nearly half of the world’s food fish consumption, and continue to be the fastest-growing animal food producing sector. The viability of aquaculture operation has greatly been affected by the characteristic of marine environment. Inventory and monitoring of marine environment are necessary and can be done through information technology implementation. Frequent monitoring of water temperature, for almost one year observation, at four aquaculture sites in Pegametan Bay and Research and Development Institute for Mariculture was investigated. Water temperature data were obtained by using logger and buoy systems. These data were contrasted against marine fish mortality. On the other hand, the suitability of species requirements with the thermal conditions was evaluated by comparing temperature range to the optimum and lethal temperature information available on marine fish species of aquaculture interest. This research could be beneficial for enhancing productivity of marine aquaculture operation in terms of possible impact of climate change. It was also possible to find the ideal temperature range for culturing fish species, taking into account the variability associated with large-scale phenomena.

  1. Cross-shelf transport into nearshore waters due to shoaling internal tides in San Pedro Bay, CA

    Science.gov (United States)

    Noble, Marlene A.; Burt Jones,; Peter Hamilton,; Xu, Jingping; George Robertson,; Leslie Rosenfeld,; John Largier,

    2009-01-01

    In the summer of 2001, a coastal ocean measurement program in the southeastern portion of San Pedro Bay, CA, was designed and carried out. One aim of the program was to determine the strength and effectiveness of local cross-shelf transport processes. A particular objective was to assess the ability of semidiurnal internal tidal currents to move suspended material a net distance across the shelf. Hence, a dense array of moorings was deployed across the shelf to monitor the transport patterns associated with fluctuations in currents, temperature and salinity. An associated hydrographic program periodically monitored synoptic changes in the spatial patterns of temperature, salinity, nutrients and bacteria. This set of measurements show that a series of energetic internal tides can, but do not always, transport subthermocline water, dissolved and suspended material from the middle of the shelf into the surfzone. Effective cross-shelf transport occurs only when (1) internal tides at the shelf break are strong and (2) subtidal currents flow strongly downcoast. The subtidal downcoast flow causes isotherms to tilt upward toward the coast, which allows energetic, nonlinear internal tidal currents to carry subthermocline waters into the surfzone. During these events, which may last for several days, the transported water remains in the surfzone until the internal tidal current pulses and/or the downcoast subtidal currents disappear. This nonlinear internal tide cross-shelf transport process was capable of carrying water and the associated suspended or dissolved material from the mid-shelf into the surfzone, but there were no observation of transport from the shelf break into the surfzone. Dissolved nutrients and suspended particulates (such as phytoplankton) transported from the mid-shelf into the nearshore region by nonlinear internal tides may contribute to nearshore algal blooms, including harmful algal blooms that occur off local beaches.

  2. Modeling Benthic Sediment Processes to Predict Water Quality and Ecology in Narragansett Bay

    Science.gov (United States)

    The benthic sediment acts as a huge reservoir of particulate and dissolved material (within interstitial water) which can contribute to loading of contaminants and nutrients to the water column. A benthic sediment model is presented in this report to predict spatial and temporal ...

  3. Water quality assessment in the Nha Trang Bay (Vietnam) by using in-situ and remotely sensed data

    NARCIS (Netherlands)

    Phan Minh Thu, T.; Schaepman, M.E.; Leemans, R.; Nguyen Tac An, A.; Tong Phuoc Hoang Son, S.; Ngo Manh Tien, T.; Phan Thanh Bac, B.

    2008-01-01

    The Nha Trang Bay (Vietnam) is an international marine protected area with significant economic, natural and recreational values. Considerable economic development is expected in particularly for tourism, navigation and aquaculture. However, in recent years the environmental quality of the Bay has b

  4. Landsat-8 imagery to estimate clarity in near-shore coastal waters: Feasibility study - Chabahar Bay, Iran

    Science.gov (United States)

    Kabiri, Keivan; Moradi, Masoud

    2016-08-01

    This study examined the advantages of incorporating the new band of Landsat-8 OLI imagery (band 1: Coastal/Aerosol, 435-451 nm) to a model for estimation of Secchi disk depth (SDD) values (as an indicator for transparency) in near-shore coastal waters using multispectral bands. In doing so, Chabahar Bay in the southern part of Iran (north of Gulf of Oman) was selected as the study area. Two approximately four-hour in-situ observations (including 48 and 56 field measured SDD values for each date respectively) were performed in the study area using Secchi disk; this was designed to start about two hours before and end about two hours after the time of satellite overpasses. Thereafter, a model was formed for estimation of SDD values based on the terms including all possible linear and mutual ratio values of Coastal/Aerosol (B1), Blue (B2), Green (B3), and Red bands (B4). In the first step, the correlation between reflectance/ratio reflectance values of these bands and Ln(SDD) values were calculated to indicate higher correlated bands/band ratios with the first field measured SDD values. Consequently, 17 combinations of highest correlated bands/band ratios were selected to estimate SDD values. In this regard, 32 points among the 48 field observations were selected to determine unknown coefficients of models using a multiple linear regression, and the rest 16 points were designated for accuracy assessment the results. Eventually, the measured SDD values in second field observations were utilized for validating the results. Final results demonstrated that combination of linear terms including B1, B2 and B3 bands and band ratio terms including ratio reflectance values of B4/B3, B3/B1, and B2/B1 has led to obtain the highest accuracy (R2=0.866 and RMSE=0.919, SVM feature weight=4.294). This was in agreement with the results obtained from the second observations. Finally, by applying the entire 104 field observed SDD values, the model in form of SDD=0.077exp(1.209RB1

  5. Pore water studies reef flat sediments, Kaneohe Bay, Oahu, HI (NODC Accession 0000271)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Geochemical behavior of the upper 70 cm of permeable reef flat sediments on Checker Reef, Oahu, Hawaii was examined using spatial and temporal changes in pore water...

  6. EnviroAtlas - Green Bay, WI - Potential Window Views of Water by Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — This EnviroAtlas dataset describes the block group population and the percentage of the block group population that has potential views of water bodies. A potential...

  7. An assessment of produced water impacts in the Galveston Bay system

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This study provides a general assessment of any adverse environmental effects resulting from tidal disposal of produced waters by: 1) documenting any alterations to...

  8. PacIOOS Water Quality Buoy 03 (WQB-03): Kiholo Bay, Big Island, Hawaii

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The water quality buoys are part of the Pacific Islands Ocean Observing System (PacIOOS) and are designed to measure a variety of ocean parameters at fixed points....

  9. Characteristics of coastal waters of the western Bay of Bengal during different monsoon seasons

    Digital Repository Service at National Institute of Oceanography (India)

    Suryanarayana, A.; Murty, C.S.; Rao, D.P.

    Physical characteristics of waters along the eastern coast of India up to offshore distances of 400 km have been investigated during the seasons of the north-easterly and south-westerly monsoons in light of relevant observed meteorological forcings...

  10. Acoustic reflections in the water column of Krishna-Godavari offshore basin, Bay of Bengal.

    Science.gov (United States)

    Sinha, Satish K; Dewangan, Pawan; Sain, Kalachand

    2016-05-01

    Seismic oceanographic studies from various oceans worldwide have indicated that the acoustic reflections are mostly observed along thermal boundaries within the water column. However, the authors present a case study of seismic data from Krishna-Godavari Basin which shows that salinity variations also play an important role in the occurrence of water column reflections. The observed reflection is modeled using the reflectivity series derived from the salinity and temperature profiles from a nearby Conductivity-Temperature-Depth (CTD) location. Sensitivity analysis of temperature and salinity on soundspeed shows that the effect of salinity cannot be ignored for modeling acoustic reflections. The synthetic seismogram matches well with the observed reflection seismic data. Remarkable similarities between the reflection seismic and the salinity profile in the upper thermocline suggest the importance of salinity variations on the water column reflection. Furthermore, impedance inversion of the reflectivity data reveals several thermohaline structures in the water column. The origin of these thermohaline structures is largely unaddressed and may be attributed to the fresh water influx coming from Himalayan and Peninsular rivers or due to the presence of different water masses in the Indian Ocean which warrants a detailed study using concurrent seismic and CTD data.

  11. On the vertical distribution of carbon monoxide over Bay of Bengal during winter: Role of water vapour and vertical updrafts

    Science.gov (United States)

    Girach, I. A.; Nair, Prabha R.

    2014-09-01

    The differences in the spatial pattern of column carbon monoxide (CO) and in-situ measured near-surface CO over Bay of Bengal (BoB) during winter were examined in the light of vertical distribution of CO as retrieved from MOPITT (Measurements Of Pollution In The Troposphere) on board Terra spacecraft. The column CO showed relatively high values over southern-BoB whereas the near-surface CO showed low mixing ratio indicating the existence of significant amount of CO at higher altitudes. The vertical profiles of CO over the BoB region retrieved from MOPITT exhibit a high altitude peak around ~9 km altitude region. The role of water vapour and convective activity/vertical updrafts in establishing the observed vertical profile of CO was investigated. It is found that CO got uplifted to the higher altitude due to updrafts and water vapour caused depletion of CO at lower altitudes which appeared as an apparent high in CO mixing ratio at higher altitude relative to that over lower altitude. The role of water vapour in the destruction of CO was confirmed by box model simulations. Airmass back-trajectory analysis showed that the long range transport from lower troposphere/boundary layer was also partially responsible for higher mixing ratios at higher altitude. In addition, a comparison of in-situ measured near-surface CO and those retrieved from MOPITT using retrieval algorithm Versions 4 and 5 showed that the points of discrepancy have reduced in the Version 5. Biomass burning and anthropogenic activities taking place over the Myanmar landmass was found to be responsible for the hot spots of near-surface-CO over the northeast-BoB.

  12. Variable influx of West Greenland Current water into the Labrador Current through the last 8000 years, based on a multiproxy study from Trinity Bay, NE Newfoundland

    DEFF Research Database (Denmark)

    Sheldon, Christina; Seidenkrantz, Marit-Solveig; Frandsen, Paul

    2015-01-01

    . This may be explained by a weaker North Atlantic subpolar gyre, transporting less Atlantic Water from the WGC to the (outer) LC. Arctic meltwater transport was reduced as glacial melting decreased at the end of the Holocene Thermal Optimum. At ca. 3 cal kyr BP, bottom waters returned to colder, more stable...... Current (WGC) Davis Strait branch, merging into the relatively cold LC. This Atlantic water influence gradually decreased after ca. 6 cal kyr BP, reaching a minimum at 5 cal kyr BP. In contrast, surface temperatures were relatively low due to cold surface water dominated by sea ice and meltwater carried...... conditions, indicating a slight decrease in bottom-water ventilation. After ca. 2.2 cal kyr BP surface water temperatures dropped and sea ice flux increased. The seafloor of Trinity Bay saw warmer conditions, consistent with a stronger subpolar gyre and increased influx of Atlantic-sourced water....

  13. Two 24-hour Studies of Water Quality in the Ala Wai Canal during March and July, 1994 for the Mamala Bay Study, Pollutant Source Identification Project MB-3, (NODC Accession 0001188)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset focuses on studies of water quality in the Ala Wai Canal in order to determine its role of point and non point source disharge into Mamala Bay. The...

  14. Temperature profile and water depth data collected from USS MOBILE BAY using BT and XBT casts in the Northwest Atlantic Ocean from 12 July 1987 to 17 July 1987 (NODC Accession 8700267)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and water depth data were collected using BT and XBT casts from the USS MOBILE BAY in the Northwest Atlantic Ocean and TOGA Area - Atlantic...

  15. Temperature profile and water depth data collected from USS MOBILE BAY using BT and XBT casts in the NW Atlantic Ocean from 15 May 1987 to 27 May 19876 (NODC Accession 8700223)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and water depth data were collected using BT and XBT casts from the USS MOBILE BAY in the Northwest Atlantic Ocean. Data were collected from 15...

  16. Aurelia labiata (Scyphozoa) jellyfish in Roscoe Bay: Their spatial distribution varies with population size and their behaviour changes with water depth

    Science.gov (United States)

    Albert, David J.

    2009-02-01

    During 2003 and 2004, there were large numbers of Aurelia labiata medusae in Roscoe Bay and they distributed themselves across the entire bay. A smaller population present during 2006 and 2007 typically formed an aggregation in the west half of the bay. Since currents would have been the same during these two time periods, the behaviour of medusae must have influenced their distribution. The way medusae spaced themselves in aggregations appeared to interact with tidal currents to produce the difference in medusae distribution during the two time periods. In a second series of observations, I found that medusae were not stranded on a Roscoe Bay beach by ebb tides. When the depth of the water column declined to about 1 m or less, medusae in an intertidal zone dove down and bumped into the bottom or swam into rocks or oysters. Their response to these collisions was to swim to the surface or within a few centimetres of the surface. Since the ebb stream was at the surface, being at the surface increased the probability that medusae drifted out of the intertidal zone. The influence of medusae behaviour on their distribution and on their avoidance of stranding is a further indication of the importance of adaptive behaviour in the ecology of Aurelia labiata medusae.

  17. Water Quality Assessment of DoD Installations/Facilities in the Chesapeake Bay Region. Phase 3. Volume 2. Overall Approach, Findings and Recommendations.

    Science.gov (United States)

    1987-11-01

    to quantify, where possible, the impacts of an installation on water quality in terms of: 1) conventional poilu - tants (nutrient, coliform and BOD...wildlife are the more visible manifestations of ecosystems in the estuary. Actually, there are many complex physico -chemical-biological interactions...that environmental stresses and rep’,- , in some areas of the Bay than in ot her.. 1l I, development of a segmentation scheme of the e ,ar. physico

  18. Near-Surface Circulation and Fate of Upper Layer Fresh Water from Rivers Runoff and Rain in the Bay of Bengal near Sri Lanka

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Near -Surface Circulation and Fate of Upper Layer Fresh...Water from Rivers Runoff and Rain in the Bay of Bengal near Sri Lanka Luca Centurioni Scripps Institution of Oceanography 9500 Gilman Drive...GOALS Improve the knowledge of the near -surface circulation in the BoB and of the pathways through which the freshwater fluxes occur. OBJECTIVES

  19. Distribution of Glass Eel by the Water Surface Salinity Using Landsat TM at Pelabuhan Ratu Bay, West Java

    Science.gov (United States)

    Irianto, D. S.; Supriatna; Pin, TjiongGiok

    2016-11-01

    Eel (Anguilla spp.) is consumed fish that has an important economic value, either for local or international market. Pelabuhanratu Bay is an area with big potential for supplying eel seed. One of important factor, which affect an eel existence, is salinity, because eel migrate from fresh water, brackish, and sea naturally although the otherwise so that need ways to describe the distribution of glass eel by the salinity. To find out the percentage of salinity, it obtained from Landsat 8 Imagery in year 2015 using salinity prediction of Algorithm Cimandiri. The research has been conducted at Cimandiri Estuary, Citepus Estuary, and Cimaja Estuary based on wet and dry months. The existence of glass eel which is obtained from the catch was occurs on dry month when the most catch was occurs at the edge of estuary. The catch is reduced if it's farther from the edge of estuary, at the beach towards the sea and the inside of the river mouth with the percentage of salinity towards the sea is increase while the percentage of salinity towards the river is decrease.

  20. The Effect of Dissolved Polyunsaturated Aldehydes on Microzooplankton Growth Rates in the Chesapeake Bay and Atlantic Coastal Waters

    Directory of Open Access Journals (Sweden)

    Peter J. Lavrentyev

    2015-05-01

    Full Text Available Allelopathy is wide spread among marine phytoplankton, including diatoms, which can produce cytotoxic secondary metabolites such as polyunsaturated aldehydes (PUA. Most studies on diatom-produced PUA have been dedicated to their inhibitory effects on reproduction and development of marine invertebrates. However, little information exists on their impact on key herbivores in the ocean, microzooplankton. This study examined the effects of dissolved 2E,4E-octadienal and 2E,4E-heptadienal on the growth rates of natural ciliate and dinoflagellate populations in the Chesapeake Bay and the coastal Atlantic waters. The overall effect of PUA on microzooplankton growth was negative, especially at the higher concentrations, but there were pronounced differences in response among common planktonic species. For example, the growth of Codonella sp., Leegaardiella sol, Prorodon sp., and Gyrodinium spirale was impaired at 2 nM, whereas Strombidium conicum, Cyclotrichium gigas, and Gymnodinium sp. were not affected even at 20 nM. These results indicate that PUA can induce changes in microzooplankton dynamics and species composition.

  1. A BAYES LIKELIHOOD INFORMATION THEORETIC APPROACH FOR THE EXOGENOUS AGGREGATION OF REGIONAL GROUND WATER QUALITY DATA

    Science.gov (United States)

    This work addresses a potentially serious problem in analysis or synthesis of spatially explicit data on ground water quality from wells, known to geographers as the modifiable areal unit problem (MAUP). It results from the fact that in regional aggregation of spatial data, inves...

  2. Water, organic matter, nitrogen and phosphorus contents in sediment of a large-scale mariculture area in the Zhelin Bay of eastern Guangdong Province, China

    Institute of Scientific and Technical Information of China (English)

    DONG Qiaoxiang; LIN Junda; SHANG Xu; LI Jin; HUANG Changjiang

    2008-01-01

    The Zhelin Bay is one of the most important bays for large-scale maricuhure in Guangdong Province,China.Owing to the increas-ing human population and the expanding marieuhure in the last two decades,the ecological environment has greatly changed with frequent harmful algal blooms.A monthly survey of water content,organic matter ( TOM ),and various forms of nitrogen and phosphorous in sediment from July 2002 to July 2003 in the bay was conducted.The results showed that the water content was cor-related significantly with TOM and various forms of nitrogen and phosphorus and can be used as proxy for quick and rough estimate of these factors in the future surveys.TOM was also correlated significantly with various forms of nitrogen and phosphorus,indica-ting that it was one of the key factors affecting the concentrations and distributions of nitrogen and phosphorus in the investigated waters. Average total Kjeldhal nitrogen (TkN) Content was( 1113.1±382.5 )μg/g and average total phosphorus (TP) content was(567.2 ± 223.3)μg/g, and both were much higher than those of similar estuaries in China and elsewhere. Average nitrogen and phosphorus tended to be higher inside than outside the bay,higher at aquaculture than non-aquacuhure areas,and higher at fish-cage culture than oyster culture areas,suggesting that large-scale mariculture inside the bay played an important role in the eutrophication of the Zhelin Bay.Various forms of nitrogen and phosphorus concentrations were higher during the warm season (July--September),which was due to the increased decomposition and concentration of organic matter resulted from the fast growth and high mortality of the cultured species.Compared with July 2002,TkN and TP contents were much higher in July 2003,in consonance with the eut~'ophication of the Zhelin Bay.Because exchangeable phosphorus ( Ex-P),iron-bounded phos-phorus (Fe-P) and organic phosphorus (OP) combined accounted for 34.3% of the TP and authigenie phosphorus (Au-P) ac

  3. 33 CFR 80.1114 - San Pedro Bay-Anaheim Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Pedro Bay-Anaheim Bay, CA. 80.1114 Section 80.1114 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1114 San Pedro Bay—Anaheim Bay,...

  4. Water Quality in the Integrated Mariculture Pond Systems (IMPS) at Makoba Bay, Zanzibar, Tanzania

    OpenAIRE

    Mmochi, A.J.; Mwandya, A.W.

    2003-01-01

    The Makoba integrated mariculture pond system project (IMPS) has been on-going since 1998. Except for a period from mid 1999 to 2001, various water quality parameters, namely temperature, salinity, pH, dissolved inorganic nutrients and dissolved oxygen concentration and saturation, have been monitored continuously. In 2002, measurement of sediment oxygen demand (SOD) and consumption of oxygen by sediments was initiated. Dissolved oxygen concentration varied from the highest mon...

  5. Acoustic reflections in the water column of Krishna-Godavari offshore basin, Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sinha, S.K.; Dewangan, P.; Sain, K.

    for reflectivity modeling to generate the synthetic seismogram. 4 III. THEORY AND METHOD A. Estimation of soundspeed in sea water Soundspeed of seawater varies with temperature (T), salinity (S) and depth (D) (or, pressure). Several empirical relationships... Oceanography: A Derivative of the Encyclopedia of Ocean Sciences, edited by J. H. Steele, S. A. Thorpe and K. K. Turekian (Academic Press, London, 2008), pp. 432-441. 32 S. Sinha, "Data driven Q-compensation using continuous wavelet transform," in SEG...

  6. Multiple stressor effects on water quality in Poplar Bay, Lake of the Woods, Canada: a midge-based assessment of hypolimnetic oxygen conditions over the last two centuries

    Directory of Open Access Journals (Sweden)

    Jamie C. Summers

    2012-01-01

    Full Text Available Chironomid and Chaoborus (midge remains preserved in a dated sediment core from Poplar Bay, Lake of the Woods (LOW, Ontario, Canada, were used to assess the effects of multiple stressors (e.g., recent warming and shoreline development on water quality over the past ~200 years. As monitoring data for LOW do not extend beyond recent decades, paleolimnological methods are used to reconstruct long-term limnological trends and to establish pre-disturbance conditions. The effects of recent warming and shoreline development on Poplar Bay water quality are examined using an index of hypolimnetic oxygen (O2 status based on the ratio of Chaoborus to chironomid remains (chaob:chir and a midge-inferred volume-weighted hypolimnetic oxygen (VWHO model. Our paleolimnological data indicate that hypolimnetic [O2] in Poplar Bay have been historically hypoxic (1-4 mg O2 L-1 but have declined further (generally <2 mg O2 L-1 over the last few decades. Significant relationships between air temperature and midge data indicate that substantial warming starting in the late-1970s has triggered a marked response in the midge assemblages that pre-dates the onset of cottage development (mid-1990s. These findings complement a diatom-based study on the same sediment core, likewise suggesting that recent warming has played a prominent role in structuring limnetic communities. However, it is likely that the full, compounded effects of recent warming and shoreline development have not yet been realized. Our study highlights the complexity of multiple stressor systems, such as Poplar Bay, and emphasizes the benefits of using multiple, independent lines of paleoenvironmental evidence in gaining a more complete understanding of historical water quality.

  7. PRESSURE - WATER and Other Data from UNKNOWN and Other Platforms From Sarasota Bay from 19810821 to 19870725 (NODC Accession 9000127)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains nutrient data with a variety of parameters measured by Mote Marine Laboratory in Sarasota Bay, FL from May 1987 to June 1987. The data was...

  8. Delineation of high water line and seasonal beach profiling at Kalbadevi Bay, Maharashtra, central west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Ganesan, P.

    collected by using highly sophisticated instruments like Laser Trak, DGPS (Differential Global Positioning System) and Automatic level (Carl Zeiss Make) following the standard survey techniques. Beach profiles at three sites in Kalbadevi bay has clearly...

  9. Polar organic compounds in pore waters of the Chesapeake Bay impact structure, Eyreville core hole: Character of the dissolved organic carbon and comparison with drilling fluids

    Science.gov (United States)

    Rostad, C.E.; Sanford, W.E.

    2009-01-01

    Pore waters from the Chesapeake Bay impact structure cores recovered at Eyreville Farm, Northampton County, Virginia, were analyzed to characterize the dissolved organic carbon. After squeezing or centrifuging, a small volume of pore water, 100 ??L, was taken for analysis by electrospray ionization-mass spectrometry. Porewater samples were analyzed directly without filtration or fractionation, in positive and negative mode, for polar organic compounds. Spectra in both modes were dominated by low-molecular-weight ions. Negative mode had clusters of ions differing by -60 daltons, possibly due to increasing concentrations of inorganic salts. The numberaverage molecular weight and weight-average molecular weight values for the pore waters from the Chesapeake Bay impact structure are higher than those reported for other aquatic sources of natural dissolved organic carbon as determined by electrospray ionization-mass spectrometry. In order to address the question of whether drilling mud fluids may have contaminated the pore waters during sample collection, spectra from the pore waters were compared to spectra from drilling mud fluids. Ions indicative of drilling mud fluids were not found in spectra from the pore waters, indicating there was no detectable contamination, and highlighting the usefulness of this analytical technique for detecting potential contamination during sample collection. ?? 2009 The Geological Society of America.

  10. Hydrology of the Poverty Bay flats aquifers, New Zealand: recharge mechanisms, evolution of the isotopic composition of dissolved inorganic carbon, and ground-water ages

    Science.gov (United States)

    Taylor, C. B.

    1994-06-01

    With the exception of water-bearing remnants of earlier fluvial gravels overlying basement, the sediments of the Poverty Bay flats have accumulated during the postglacial period of the past 14 000 years, and have been tilted and deformed by recent tectonism. A sequence of gravel aquifers, separated by poorly permeable silt layers, lies between surface and basement, which is at depths varying between 50 and 200 m. A shallow sand/silt aquifer is situated near the coast. This study applies evidence of chemical and isotopic properties of river and ground water to clarify the recharge mechanisms, chemical evolution and age of the ground water in the aquifers. Particular attention is paid to the evolution of dissolved inorganic carbon content, applying carbon-14 data measured by accelerator mass spectrometry. Most of the ground water is recharged from the Waipaoa River, which flows across the flats and discharges into Poverty Bay. The two deepest aquifers (Matokitoki and Makauri) are both tritium-free; the deeper Matokitoki Gravels yield water of age about 4300 years since recharge (possibly up to 1300 years greater), but the Makauri water is no older than 100-200 years, discharging slowly through overlying aquitards near the limit of closest approach to the present coast.

  11. How can climate change and engineered water conveyance affect sediment dynamics in the San Francisco Bay-Delta system?

    Science.gov (United States)

    Achete, Fernanda; Van der Wegen, Mick; Roelvink, Jan Adriaan; Jaffe, Bruce E.

    2017-01-01

    Suspended sediment concentration is an important estuarine health indicator. Estuarine ecosystems rely on the maintenance of habitat conditions, which are changing due to direct human impact and climate change. This study aims to evaluate the impact of climate change relative to engineering measures on estuarine fine sediment dynamics and sediment budgets. We use the highly engineered San Francisco Bay-Delta system as a case study. We apply a process-based modeling approach (Delft3D-FM) to assess the changes in hydrodynamics and sediment dynamics resulting from climate change and engineering scenarios. The scenarios consider a direct human impact (shift in water pumping location), climate change (sea level rise and suspended sediment concentration decrease), and abrupt disasters (island flooding, possibly as the results of an earthquake). Levee failure has the largest impact on the hydrodynamics of the system. Reduction in sediment input from the watershed has the greatest impact on turbidity levels, which are key to primary production and define habitat conditions for endemic species. Sea level rise leads to more sediment suspension and a net sediment export if little room for accommodation is left in the system due to continuous engineering works. Mitigation measures like levee reinforcement are effective for addressing direct human impacts, but less effective for a persistent, widespread, and increasing threat like sea level rise. Progressive adaptive mitigation measures to the changes in sediment and flow dynamics resulting from sea level rise may be a more effective strategy. Our approach shows that a validated process-based model is a useful tool to address long-term (decades to centuries) changes in sediment dynamics in highly engineered estuarine systems. In addition, our modeling approach provides a useful basis for long-term, process-based studies addressing ecosystem dynamics and health.

  12. 76 FR 37641 - Safety Zone; Independence Day Fireworks Celebration for the City of Half Moon Bay, Half Moon Bay, CA

    Science.gov (United States)

    2011-06-28

    ... the City of Half Moon Bay, Half Moon Bay, CA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone in the navigable waters of Half Moon Bay, off of Pillar Point Harbor beach, Half Moon Bay, CA in support of the Independence Day...

  13. 78 FR 62293 - Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay; Oyster Bay, NY

    Science.gov (United States)

    2013-10-15

    ... CFR Part 165 RIN 1625-AA00 Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay; Oyster Bay, NY AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing a temporary safety zone on the navigable waters of Oyster Bay near Oyster Bay, NY for the...

  14. A Lagrangian Physical-Biological Model to Study Water Parcels Associated with Algal Blooms from Southern California Bight to Todos Santos Bay.

    Science.gov (United States)

    Vivas Téllez, I. E.; Rivas, D.

    2015-12-01

    Lagrangian ocean circulation and biological dynamics are numerically studied in Todos Santos Bay during the spring of 2007. This period is particularly interesting after an intense toxic algal bloom occurred in April 2007 in this area, which was associated with the wind-driven upwelling in the region. High resolution, numerical model simulations were carried out to study dynamical features along of the Southern California Bight (SCB), the coast of the northern Baja California (BC), and the interior of Todos Santos Bay (TSB). These simulations are used in a three-dimensional Lagrangian (particle tracking) analysis which provides information about the origin and distribution of the waters present in the Bay during the occurrence of the toxic bloom. After the selection of trajectories of particles showing coherent patterns, a Nitrate-Phytoplankton-Zooplankton-Detritus (NPZD) lower trophic model is implemented to study the influence of the environmental conditions that occur during the particle advection, solving the NPZD equations at every time-varying position of the advected particles. The model is also modified for phytoplankton growth as a function of the environmental temperature to somehow emulate the life cycle of Pseudo-nitzschia. The analysis of the trajectories shows that particles mainly come from two regions: from the north, in the southern portion of SCB and from regions west of the TSB. Knowing the regional circulation patterns and their phytoplankton dynamics can help to understand and even predict the origin and destination of the harmful algal blooms that occur in TSB and its surroundings.

  15. Water Use Efficiency Improvement against a Backdrop of Expanding City Agglomeration in Developing Countries—A Case Study on Industrial and Agricultural Water Use in the Bohai Bay Region of China

    Directory of Open Access Journals (Sweden)

    Minghao Bai

    2017-02-01

    Full Text Available Most city agglomerations of developing countries face water shortages and pollution due to population growth and industrial aggregation. To meet such water security challenges, policy makers need to evaluate water use efficiency at the regional or basin level because the prosperity of city agglomerations is indispensable to the sustainable development of the region or basin. To solve the issue, this paper adopts a non-directional distance function within the framework of environmental production technology to measure water use efficiency. Based on the distance between actual water use efficiency and the ideal efficiency, it calculates the potential reduction space of water input and pollutants by slack adjustment. Added to the Malmquist index, it forms a non-radial Malmquist water use performance index, which can be divided into technological change and technical efficiency change, to measure dynamic water use efficiency. Further, water use efficiency change is analyzed from the perspectives of technological improvement and institutional construction. Bohai Bay city agglomeration, a typical water-deficient city agglomeration in China, is taken as a case study, and data on water resource, environment, and economy from 2011 to 2014 have been used. In conclusion, there is much space for water use efficiency improvement on the whole. However, even having considered potential reduction space of water input and pollutant discharge under current environmental production technology, it is still not enough to support the city agglomeration’s sustainable development. To relieve current potential water safety hazards, not only technical improvement but also institution innovation for highly efficient water use should be kept accelerating in Bohai Bay region. In terms of urban water management in developing countries, the research conclusion is of theoretical and practical significance.

  16. Application of geologic map information to water quality issues in the southern part of the Chesapeake Bay watershed, Maryland and Virginia, eastern United States

    Science.gov (United States)

    McCartan, L.; Peper, J.D.; Bachman, L.J.; Horton, J.W.

    1999-01-01

    Geologic map units contain much information about the mineralogy, chemistry, and physical attributes of the rocks mapped. This paper presents information from regional-scale geologic maps in Maryland and Virginia, which are in the southern part of the Chesapeake Bay watershed in the eastern United States. The geologic map information is discussed and analyzed in relation to water chemistry data from shallow wells and stream reaches in the area. Two environmental problems in the Chesapeake Bay watershed are used as test examples. The problems, high acidity and high nitrate concentrations in streams and rivers, tend to be mitigated by some rock and sediment types and not by others. Carbonate rocks (limestone, dolomite, and carbonate-cemented rocks) have the greatest capacity to neutralize acidic ground water and surface water in contact with them. Rocks and sediments having high carbon or sulfur contents (such as peat and black shale) potentially contribute the most toward denitrification of ground water and surface water in contact with them. Rocks and sediments that are composed mostly of quartz, feldspar, and light-colored clay (rocks such as granite and sandstone, sediments such as sand and gravel) tend not to alter the chemistry of waters that are in contact with them. The testing of relationships between regionally mapped geologic units and water chemistry is in a preliminary stage, and initial results are encouraging.Geologic map units contain much information about the mineralogy, chemistry, and physical attributes of the rocks mapped. This paper presents information from regional-scale geologic maps in Maryland and Virginia, which are in the southern part of the Chesapeake Bay watershed in the eastern United States. The geologic map information is discussed and analyzed in relation to water chemistry data from shallow wells and stream reaches in the area. Two environmental problems in the Chesapeake Bay watershed are used as test examples. The problems, high

  17. 78 FR 39610 - Safety Zone; Big Bay Boom, San Diego Bay; San Diego, CA

    Science.gov (United States)

    2013-07-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Boom, San Diego Bay; San Diego, CA... temporary safety zones upon the navigable waters of the San Diego Bay for the annual Port of San Diego... Sector San Diego, Coast Guard; telephone 619-278-7261, email d11marineeventssd@uscg.mil . If you have...

  18. 78 FR 29289 - Safety Zone; Big Bay Boom, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2013-05-20

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Boom, San Diego Bay, San Diego, CA... establish four temporary safety zones upon the navigable waters of San Diego ] Bay for the Port of San Diego... Management, U.S. Coast Guard Sector San Diego; telephone (619) 278-7261, email John.E.Bannon@uscg.mil . If...

  19. Validation and Analysis of Water Column Correction Algorithm at Sanya Bay%水体校正模型在三亚湾的验证及分析

    Institute of Scientific and Technical Information of China (English)

    杨超宇; 杨顶田; 叶海彬; 曹文熙

    2011-01-01

    水体校正一直是光学浅水遥感检测中的重点难题.为了提高三亚湾底质遥感监测精度,分别采用理想水体光辐射分布和Christian模型剔除水体信号的影响,尝试从水面之下遥感反射率信号中提取其底质光谱反射率值.结果表明,两种模型模拟结果差异较大,其模拟与实测值的相关性分别是0.93和0.26.经分析认为Christian模型在三亚湾湾内水域失效的这一结果与三亚湾光学浅水和光学深水的差异性相关.三亚湾湾内水域光学性质复杂,光学参数随着地理坐标位置变化较大,即使在光学浅水水域内的邻近站点,其衰减系数也是具有较大差异的.因而,Christian的模型在此区域很难发挥出优势.%Water column correction has been a substantial challenge for remote sensing. In order to improve the accuracy of coastal ocean monitoring where optical properties are complex, optical property of shallow water at Sanya Bay and the suitable water column correction algorithms were studies in the present paper. The authors extracted the bottom reflectance without water column effects by using a water column correction algorithm which is based on the simulation of the underwater light field in idealized water. And we compared the results which were calculated by the model and Christian's model respectively. Based on a detailed analysis, we concluded that: Because the optical properties of Sanya Bay are complex and vary greatly with location,Christian's model lost its advantage in the area. Conversely, the bottom reflectance calculating by the algorithm based on the simulation of the underwater light field in idealized water agreed well with in situ measured bottom reflectance, although the reflectance was lower than in situ measured reflectance value between 400 and 500 nm. So, it is reasonable to extract bottom information by using the water column correction algorithm in local bay area where optical properties are complex.

  20. Study of total column atmospheric aerosol optical depth, ozone and precipitable water content over Bay of Bengal during BOBMEX-99

    Indian Academy of Sciences (India)

    K K Dani; R S Maheskumar; P C S Devara

    2003-06-01

    The spatial and temporal variations in aerosols and precursor gases over oceanic regions have special importance in the estimation of radiative forcing parameters and thereby in the refinement of general circulation models. Extensive observations of the columnar aerosol optical depth (AOD), total column ozone (TCO) and precipitable water content (PWC) have been carried out using the on-line, multi-band solar radiometers onboard ORV Sagar Kanya (Cruise#SK 147B) over Bay of Bengal during 11th-28th August 1999. Aerosol optical and physical properties (optical depth and angstrom parameter) have been estimated at six wavelengths covering from UV to NIR (380-1020 nm) while TCO and PWC have been determined using the UV band around 300nm and NIR band around 940 nm, respectively. Added, concurrent meteorological and satellite observations during this field phase of BOBMEX-99 have been utilized to investigate spectral-temporal variations of AOD, TCO and PWC in marine environment. The results indicate lower AODs (around 0.4 at characteristic wavelength of 500 nm) and size distributions with abundance of coarse-mode particles as compared to those aerosols of typical land origin. An interesting result that is found in the present study is the significant reduction in AOD at all wavelengths from initial to later part of observation period due to cloud-scavenging and rain-washout effects as well as signature of coastal aerosol loading. The clear-sky daytime diurnal variation of TCO shows gradual increase during post-sunrise hours, broad maximum during afternoon hours and gradual decrease during pre-sunset hours, which is considered to be due to photochemical reactions. The diurnal variation curve of PWC showed maximum (∼4cm) during morning hours and gradual decrease (∼3.5cm) towards evening hours, which are found to be greater as compared to typical values over land. Another interesting feature observed is that although the PWC values are very high, there was no proportionate

  1. Biogeochemical redox cycling of arsenic in mine-impacted lake sediments and co-existing pore waters near Giant Mine, Yellowknife Bay, Canada

    Energy Technology Data Exchange (ETDEWEB)

    Andrade, C.F. [Queen' s University, Department of Geological Sciences and Geological Engineering, Kingston, K7L 3N6 (Canada); Jamieson, H.E., E-mail: jamieson@geol.queensu.ca [Queen' s University, Department of Geological Sciences and Geological Engineering, Kingston, K7L 3N6 (Canada); Kyser, T.K. [Queen' s University, Department of Geological Sciences and Geological Engineering, Kingston, K7L 3N6 (Canada); Praharaj, T.; Fortin, D. [University of Ottawa, Department of Earth Sciences, Ottawa, K1A 3N5 (Canada)

    2010-02-15

    Lacustrine sediments, submerged tailings, and their pore waters have been collected at several sites in Yellowknife Bay, Great Slave Lake, Canada, in order to investigate the biogeochemical controls on the remobilization of As from mining-impacted materials under different depositional conditions. Radiometric dating confirms that a mid-core enrichment of Pb, Zn, Cu and Sb corresponds to the opening of a large Au mine 60 a ago. This was evident even in a relatively remote site. Arsenic was enriched at mid-core, coincident with mining activity, but clearly exhibited post-depositional mobility, migrating upwards towards the sediment water interface (SWI) as well as down-core. Deep-water (15 m) Yellowknife Bay sediments that contain buried mine waste are suboxic, relatively organic-rich and abundant in microbes with As in pore waters and sediments reaching 585 {mu}g/L and 1310 mg/kg, respectively. Late summer pore waters show equal proportions of As(III) and As(V) (16-415 {mu}g/L) whereas late winter pore waters are dominated by As(III) (284-947 {mu}g/L). This can be explained by As(III) desorption mechanisms associated with the conversion of FeS to FeS{sub 2} and the reduction of As(V) to As(III) through the oxidation of dissolved sulfide, both microbially-mediated processes. Processes affecting As cycling involve the attenuating efficiency of the oxic zone at the SWI, sediment redox heterogeneity and the reductive dissolution of Fe(hydr)oxides by labile organic matter, temporarily and spatially variable.

  2. Fresh Water River discharges as observed by SMOS in the Arabian Sea and the Bay of Bengal

    Science.gov (United States)

    Olmedo, Estrella; Ballabrera-Poy, Joaquim; Turiel, Antonio

    2017-04-01

    The Bay of Bengal (BoB) and the Arabian Sea (AS) are two peculiar regions in the Indian Ocean exhibiting a wide range of Sea Surface Salinity (SSS) values. In the BoB, the strong summer monsoon rainfall and the continental run-offs into these semi-enclosed basins result in an intense dilution of the surface seawater in the northern part of the Bay, thereby inducing some of the lowest SSS water masses found in the tropical belt. In the AS, because of the intense variability associated with the monsoon cycle, water mass structure in the upper layers of the AS shows enormous variability in the space and time. As such, the role of the salinity in these regions is crucial in the ocean dynamics of these regions. After more than 7 years in orbit, the Soil Moisture and Ocean Salinity (SMOS) mission [1] continues to provide a series of salinity data that could be used to monitor the SSS variations in these climatically relevant regions, provided that systematic errors due to land contamination are reduced. Recently-developed algorithms for SSS retrieval [2] have improved the filtering criteria and the mitigation of the systematic bias, providing coherent SSS retrievals close to the land masses. In this work we have analyzed the SSS in 2-degree boxes located at the mouth of the main rivers in the BoB: Ganges-Brahmaputra, Irrawady, Mahanadi, Godovari; and in the AS: Indus. We have first tried to validate the SMOS salinity retrievals with in situ measurements. Since there is few available in situ data, we have also compared the climatological SSS behavior derived from SMOS with the ones provided by the World Ocean Atlas [3]. We have also compared the SMOS SSS data with historical data of discharges [4] and [5], ocean currents from the Ocean Surface Current Analyses Real-time (OSCAR) [6], Sea Surface Temperature from Operational Sea Surface Temperature and Sea Ice Analysis (OSTIA) [7],[8] and [9] and Chlorophyll data [10]. The conclusion of this work is that, when the proper

  3. A Review of Use of GIS for the Evaluation of Heavy Metal and Water Quality Parameters in the Canal do Cunha Watershed and west of the Guanabara Bay, Rio de Janeiro (Brazil

    Directory of Open Access Journals (Sweden)

    Renata Coura Borges

    2016-06-01

    Full Text Available As well as other sub-basins of the Guanabara Bay, the Canal do Cunha watershed, located in the Rio de Janeiro city, has suffered severe environmental degradation since the 50s, due to accelerated urban-industrial development. The fluvial dynamics has changed by the deforestation, landfill constructions, drainage and vale occupation. Canal do Cunha deliver wastewaters and sediments at the western side of Guanabara Bay. Contribute to the environmental degradation and has direct influence on the water quality indexes and heavy metal contamination at the western side of Guanabara Bay. This study intends to evaluate, through geoprocessing techniques, the spatial distribution of Lead (Pb, Zinc (Zn, dissolved oxygen (DO and total phosphorus (total P concentrations and pH values, using data provided by six monitoring stations of the Instituto Estadual do Ambiente – INEA (State Environmental Institute. This work allows to observe the influence of weather conditions on Pb and Zn concentrations in superficial waters and surface sediments and the behavior of DO, pH and total P of superficial waters before and after the implementation of the remediation program: Programa de Despoluição da Baía de Guanabara (PDBG; Pollution Remediation Program of Guanabara Bay. Canal do Cunha flow has direct influence on the low quality indexes of water and contributes to the heavy metal contamination and environmental degradation of the western region of Guanabara Bay.

  4. Assessment of a Mega-Float on water quality and ecosystem in Tokyo bay; Choogata futaishiki kaiyo kozobutsu ga Tokyowan no suishitsu to seitaikei ni oyobosu eikyo ni tsuite

    Energy Technology Data Exchange (ETDEWEB)

    Kyozuka, Y.; Hu, C.; Hasemi, H. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hikai, A.

    1997-08-01

    The effect on the marine environment in the bay when a Mega-Float is installed in a bay was investigated. The physical process such as a residual flow (including tidal currents, water temperature, salt, density, and density currents), and the ecosystem model for which floating organic matter and plankton are handled were incorporated to develop a program for water quality calculation in a bay. The program was used for Tokyo Bay and compared with the conventional calculation result and the oceanograhpic observation result. Simultaneously, the effect on the Mega-Float was considered. On the flow in Tokyo Bay in summer, the calculation result that comparatively coincided with the observation value in a residual flow level was obtained. The horizontal distribution of COD comparatively coincides with the existing observation result. The influence that the Mega-Float exerts on the flow, water temperature, water quality, and ecosystem in the ambient sea area was little and local in the calculation scale (L {times} B {times} d = 6 km {times} 3 km {times} 2 m) of this time. However, the difference occurring due to the design position must also be investigated in future. 12 refs., 8 figs., 5 tabs.

  5. Simulation of Pollutant Transport in Marmaris Bay

    Institute of Scientific and Technical Information of China (English)

    Lale BALAS

    2001-01-01

    The circulation pattern and the pollutant transport in the Marmaris Bay are simulated by the developed three-dimensional baroclinic model. The Marmaris Bay is located at the Mediterranean Sea coast of Turkey. Since the sp ring tidal range is typically 20~30 cm, the dominant forcing for the circulation and water exchange is due to the wind action. In the Marmaris Bay, there is sea outfall discharging directly into the bay, and that threats the bay water quality significantly. The current patterns in the vicinity of the outfall have been observed by tracking drogues which are moved by currents at different water depths. In the simulations of pollutant transport, the coliforms-counts is used as the tracer.The model provides realistic predictions for the circulation and pollutant transport in the Marmaris Bay. The transport model component predictions well agree with the results of a laboratory model study.

  6. Is drinking water a risk factor for endemic cryptosporidiosis? A case-control study in the immunocompetent general population of the San Francisco Bay Area

    Directory of Open Access Journals (Sweden)

    Nadle Joelle

    2003-03-01

    Full Text Available Abstract Background Cryptosporidiosis, caused by Cryptosporidium, is an enteric illness that has received much attention as an infection of immunocompromised persons as well as in community outbreaks (frequently waterborne. There are, however, no studies of the risk factors for sporadic community-acquired cryptosporidiosis in the immunocompetent US population. We undertook a case-control study in the San Francisco Bay Area as part of a national study sponsored by the Centers for Disease Control and Prevention to ascertain the major routes of transmission for endemic cryptosporidiosis, with an emphasis on evaluating risk from drinking water. Methods Cases were recruited from a population-based, active surveillance system and age-matched controls were recruited using sequential random-digit dialing. Cases (n = 26 and controls (n = 62 were interviewed by telephone using a standardized questionnaire that included information about the following exposures: drinking water, recreational water, food items, travel, animal contact, and person-to-person fecal contact, and (for adults sexual practices. Results In multivariate conditional logistic regression analyses no significant association with drinking water was detected. The major risk factor for cryptosporidiosis in the San Francisco Bay Area was travel to another country (matched odds ratio [95% confidence interval]: 24.1 [2.6, 220]. Conclusion The results of this study do not support the hypothesis that drinking water is an independent risk factor for cryptosporidiosis among the immunocompetent population. These findings should be used to design larger studies of endemic cryptosporidiosis to elucidate the precise mechanisms of transmission, whether waterborne or other.

  7. 33 CFR 117.1101 - Sturgeon Bay.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Sturgeon Bay. 117.1101 Section 117.1101 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY BRIDGES DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Wisconsin § 117.1101 Sturgeon Bay. (a) The draw of the Michigan Street Bridge, mile 4.3 at Sturgeon...

  8. Bottle data collected for chemical analysis along the coastal waters of Hawai'i as part of the Windward Community College Heeia Stream and Kaneohe Bay Water Quality Assessment Project from May 22, 2004 to March 19, 2005 (NODC Accession 0002449)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Measurements of water quality parameters were taken by Windward Community College faculty and students at eight sites in the Heeia Stream and adjacent Kaneohe Bay...

  9. Summary of oceanographic and water-quality measurements in Chincoteague Bay, Maryland and Virginia, 2014–15

    Science.gov (United States)

    Suttles, Steven E.; Ganju, Neil K.; Brosnahan, Sandra M.; Montgomery, Ellyn T.; Dickhudt, Patrick J.; Beudin, Alexis; Nowacki, Daniel J.; Martini, Marinna A.

    2017-05-25

    U.S. Geological Survey scientists and technical support staff measured oceanographic, waterquality, seabed-elevation-change, and meteorological parameters in Chincoteague Bay, Maryland and Virginia, during the period of August 13, 2014, to July 14, 2015, as part of the Estuarine Physical Response to Storms project (GS2–2D) supported by the Department of the Interior Hurricane Sandy recovery program. These measurements provide time series data that quantify the response and can be used to better understand the resilience of this back-barrier estuarine system to storms. The Assateague Island National Seashore (National Park Service) and the Chincoteague National Wildlife Refuge (U.S. Fish and Wildlife Service) are on the east side of Chincoteague Bay.

  10. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California: 2014

    Science.gov (United States)

    Cain, Daniel J.; Thompson, Janet K.; Crauder, Jeff; Parcheso, Francis; Stewart, Robin; Kleckner, Amy E.; Dyke, Jessica; Hornberger, Michelle I.; Luoma, Samuel N.

    2015-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer (km) south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2014 to December 2014. These append to long-term datasets extending back to 1974, and serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. 

  11. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California-2010

    Science.gov (United States)

    Dyke, Jessica; Parcheso, Francis; Thompson, Janet K.; Cain, Daniel J.; Luoma, Samuel N.; Hornberger, Michelle I.

    2011-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected for the period January 2010 to December 2010 and extends a critical long-term biogeochemical record that dates back to 1974. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program initiated in 1994.

  12. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California; 2015

    Science.gov (United States)

    Cain, Daniel J.; Thompson, Janet K.; Crauder, Jeffrey; Parchaso, Francis; Stewart, Robin; Turner, Matthew A.; Hornberger, Michelle I.; Luoma, Samuel N.

    2016-07-22

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, California. This report includes data collected by U.S. Geological Survey (USGS) scientists for the period from January 2015 to December 2015. These data are appended to long-term datasets extending back to 1974, and serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994.

  13. Time-series of water column alkenones and 18S rRNA confirm that Uk'37 is a viable SST proxy in Narragansett Bay, RI

    Science.gov (United States)

    Salacup, J.; Theroux, S.; Herbert, T.; Prell, W. L.

    2011-12-01

    Alkenones, produced in the sunlit mixed layer by specific Haptophyte algae, are a well-established and widely-applied proxy for sea surface temperature (SST) in the world's open-oceans. However, the proxy's utility in estuarine environments remains largely untested. A reliable SST proxy is needed to identify the estuary's sensitivity and response to past and present global change because SST can exert strong control on stratification and circulation patterns, and thus oxygenation and ecosystem health, in these shallow basins. Knowing the estuaries response should help local managers and policy-makers plan mitigation and adaptation strategies. Additionally, the rapid deposition of both marine and terrestrial organic and inorganic material in estuarine systems makes them potential archives of high-resolution paleo-environmental information. A previous investigation of estuarine alkenones suggested that the Uk'37 proxy may be sensitive to the composition of the alkenone-producing Haptophyte population, which may be affected by local nutrient and fresh water fluxes. In particular, low-salinity coastal Haptophytes such as Isochrysis galbana may have a different relationship to SST than higher-salinity open-ocean Haptophytes and their presence may complicate interpretations of the Uk'37 proxy in estuaries. To better understand how the alkenone-based Uk'37 SST proxy is produced in estuarine systems, we present a two-year time-series (monthly-to-thrice-weekly resolution) of alkenone concentrations in particulate organic matter from Narragansett Bay. Alkenone concentrations are coupled with 18S ribosomal RNA (rRNA) measurements to identify the alkenone-producing population. Highest concentrations of alkenones are detected at different times in the upper and lower Bay such that the highest alkenone concentrations occur in the winter-spring (upper Bay) and summer/fall (lower Bay). This result is consistent with the established seasonal blooms and seasonal changes in nutrient

  14. 33 CFR 100.112 - Swim the Bay, Narragansett Bay, Narragansett, RI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Swim the Bay, Narragansett Bay, Narragansett, RI. 100.112 Section 100.112 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.112 Swim the...

  15. Examination of factors dominating the sediment-water diffusion flux of DDT-related compounds measured by passive sampling in an urbanized estuarine bay.

    Science.gov (United States)

    Feng, Yan; Wu, Chen-Chou; Bao, Lian-Jun; Shi, Lei; Song, Lin; Zeng, Eddy Y

    2016-12-01

    The fate of hydrophobic organic compounds in aquatic environment are largely determined by their exchange at sediment-water interface, which is highly dynamic and subject to rapidly evolving environmental conditions. In turn, environmental conditions may be governed by both physicochemical parameters and anthropogenic events. To examine the importance of various impact factors, passive sampling devices were deployed at the seafloor of Hailing Bay, an urbanized estuarine bay in Guangdong Province of South China to measure the sediment-water diffusion fluxes of several metabolites of dichlorodiphenyltrichloroethane (DDT), p,p'-DDE, p,p'-DDD and o,p'-DDD. The physicochemical properties of water (temperature, pH, salinity and dissolved oxygen) and surface sediment (sediment organic matter, physical composition, pH, water content, colony forming unit and catalase activity) were also measured. The results showed that the diffusion fluxes of o,p'-DDD, p,p'-DDD and p,p'-DDE at sites A1 and A2 near a fishing boat maintenance facility ranged from 0.42 to 4.73 ng m(-2) d(-1) (from sediment to overlying water), whereas those at offshore sites varied between -0.03 and -3.02 ng m(-2) d(-1) (from overlying water to sediment), implicating A1 and A2 as the sources of the target compounds. The distribution patterns of the diffusion fluxes of the target compounds were different from those of water and sediment parameters (water temperature, salinity, sediment texture, pH, colony forming unit and catalase activity) at six sampling sites. This finding suggested that none of these parameters were critical in dictating the sediment-water diffusion fluxes. Besides, decreases in the contents of kerogen and black carbon by 6.7% and 11% would enhance the diffusion fluxes of the target compounds by 11-14% and 12-23%, respectively, at site A1, indicating that kerogen and black carbon were the key factors in mediating the sediment-water diffusion fluxes of DDT-related compounds in field

  16. Comparing effects of land reclamation techniques on water pollution and fishery loss for a large-scale offshore airport island in Jinzhou Bay, Bohai Sea, China.

    Science.gov (United States)

    Yan, Hua-Kun; Wang, Nuo; Yu, Tiao-Lan; Fu, Qiang; Liang, Chen

    2013-06-15

    Plans are being made to construct Dalian Offshore Airport in Jinzhou Bay with a reclamation area of 21 km(2). The large-scale reclamation can be expected to have negative effects on the marine environment, and these effects vary depending on the reclamation techniques used. Water quality mathematical models were developed and biology resource investigations were conducted to compare effects of an underwater explosion sediment removal and rock dumping technique and a silt dredging and rock dumping technique on water pollution and fishery loss. The findings show that creation of the artificial island with the underwater explosion sediment removal technique would greatly impact the marine environment. However, the impact for the silt dredging technique would be less. The conclusions from this study provide an important foundation for the planning of Dalian Offshore Airport and can be used as a reference for similar coastal reclamation and marine environment protection. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

  17. Understanding the Impact of Open-Framework Conglomerates on Water-Oil Displacements: Victor Interval of the Ivishak Reservoir, Prudhoe Bay Field, Alaska

    CERN Document Server

    Gershenzon, Naum I; Ritzi, Robert W; Dominic, David F

    2014-01-01

    The Victor Unit of the Ivishak Formation in the Prudhoe Bay Oilfield is characterized by high net-to-gross fluvial sandstones and conglomerates. The highest permeability is found within sets of cross-strata of open-framework conglomerate (OFC). They are preserved within unit bar deposits and assemblages of unit bar deposits within compound (braid) bar deposits. They are thief zones limiting enhanced oil recovery. We incorporate recent research that has quantified important attributes of their sedimentary architecture within preserved deposits. We use high-resolution models to demonstrate the fundamental aspects of their control on oil production rate, water breakthrough time, and spatial and temporal distribution of residual oil saturation. We found that when the pressure gradient is oriented perpendicular to the paleoflow direction, the total oil production and the water breakthrough time are larger, and remaining oil saturation is smaller, than when it is oriented parallel to paleoflow. The pressure differe...

  18. Ground-Water Quality Data in the Monterey Bay and Salinas Valley Basins, California, 2005 - Results from the California GAMA Program

    Science.gov (United States)

    Kulongoski, Justin T.; Belitz, Kenneth

    2007-01-01

    Ground-water quality in the approximately 1,000-square-mile Monterey Bay and Salinas Valley study unit was investigated from July through October 2005 as part of the California Ground-Water Ambient Monitoring and Assessment (GAMA) program. The study was designed to provide a spatially unbiased assessment of raw ground-water quality, as well as a statistically consistent basis for comparing water quality throughout California. Samples were collected from 94 public-supply wells and 3 monitoring wells in Monterey, Santa Cruz, and San Luis Obispo Counties. Ninety-one of the public-supply wells sampled were selected to provide a spatially distributed, randomized monitoring network for statistical representation of the study area. Six wells were sampled to evaluate changes in water chemistry: three wells along a ground-water flow path were sampled to evaluate lateral changes, and three wells at discrete depths from land surface were sampled to evaluate changes in water chemistry with depth from land surface. The ground-water samples were analyzed for volatile organic compounds (VOCs), pesticides, pesticide degradates, nutrients, major and minor ions, trace elements, radioactivity, microbial indicators, and dissolved noble gases (the last in collaboration with Lawrence Livermore National Laboratory). Naturally occurring isotopes (tritium, carbon-14, helium-4, and the isotopic composition of oxygen and hydrogen) also were measured to help identify the source and age of the sampled ground water. In total, 270 constituents and water-quality indicators were investigated for this study. This study did not attempt to evaluate the quality of water delivered to consumers; after withdrawal from the ground, water typically is treated, disinfected, and (or) blended with other waters to maintain water quality. In addition, regulatory thresholds apply to treated water that is served to the consumer, not to raw ground water. In this study, only six constituents, alpha radioactivity, N

  19. Spatial distribution of dissolved neodymium and ɛNd in the Bay of Bengal: Role of particulate matter and mixing of water masses

    Science.gov (United States)

    Singh, Satinder Pal; Singh, Sunil Kumar; Goswami, Vineet; Bhushan, Ravi; Rai, Vinai Kumar

    2012-10-01

    The concentration and isotope composition of dissolved Nd have been measured in the water column along an 87°E transect (GIO1 section of International GEOTRACES Program) in the Bay of Bengal (BoB) to investigate the effect of water mass mixing and Nd release from particulate matter in determining these properties. The concentration of Nd in surface waters of the BoB shows a North-South decreasing non-linear trend (˜46 to ˜22 pmol/kg) with salinity, whereas its depth profiles typically show a high value in surface waters, a minimum (˜15 to ˜23 pmol/kg) in the shallow subsurface (˜50-200 m), followed by a gradual increase with depth. The Nd concentration of BoB waters is generally higher than that in nearby oceanic basins. On the other hand, the ɛNd values in the BoB are less radiogenic compared to those reported for other regions of the global oceans (except Baffin Bay, the North Atlantic Subpolar Gyre and the Niger delta margin), and show a greater variation in the upper water column. Surface waters of the southernmost profile (˜6°N) show a more radiogenic ɛNd value ˜-8, which decreases to -15 in the northernmost profile (˜20°N), close to the values for dissolved and particulate phases of the Ganga-Brahmaputra (G-B) Rivers. This latitudinal trend is most likely a result of variations in mixing proportion between the more radiogenic Indonesian Throughflow surface waters (IW) and unradiogenic BoB low salinity water; the former's signature being more clearly discernible in surface waters of the two southernmost profiles (˜6°N and ˜8.5°N). Attempts to balance the Nd budget in the water column based on an inversion model, suggest that in addition to water masses other source(s) is required, the strength of which is estimated to vary from 1% to 65% of the measured Nd concentration. The calculations also show that the ɛNd of this additional source(s) has to be in the range of ˜-16 ± 2, typical of G-B river sediments. These observations, coupled with

  20. A model assessment of the ability of lake water in Terra Nova Bay, Antarctica, to induce the photochemical degradation of emerging contaminants.

    Science.gov (United States)

    Minella, Marco; Maurino, Valter; Minero, Claudio; Vione, Davide

    2016-11-01

    The shallow lakes located in Terra Nova Bay, Antarctica, are free from ice for only up to a couple of months (mid December to early/mid February) during the austral summer. In the rest of the year, the ice cover shields the light and inhibits the photochemical processes in the water columns. Previous work has shown that chromophoric dissolved organic matter (CDOM) in these lakes is very reactive photochemically. A model assessment is here provided of lake-water photoreactivity in field conditions, based on experimental data of lake water absorption spectra, chemistry and photochemistry obtained previously, taking into account the water depth and the irradiation conditions of the Antarctic summer. The chosen sample contaminants were the solar filter benzophenone-3 and the antimicrobial agent triclosan, which have very well known photoreactivity and have been found in a variety of environmental matrices in the Antarctic continent. The two compounds would have a half-life time of just a few days or less in the lake water during the Antarctic summertime, largely due to reaction with CDOM triplet states ((3)CDOM*). In general, pollutants that occur in the ice and could be released to lake water upon ice melting (around or soon after the December solstice) would be quickly photodegraded if they undergo fast reaction with (3)CDOM*. With some compounds, the important (3)CDOM* reactions might favour the production of harmful secondary pollutants, such as 2,8-dichlorodibenzodioxin from the basic (anionic) form of triclosan.

  1. Long-term, High Frequency, High Precision pH Measurements on the MBARI deep-water FOCE Experiment at the MARS Cabled Observatory in Monterey Bay, CA

    Science.gov (United States)

    Peltzer, E. T.; Maughan, T.; Barry, J. P.; Brewer, P. G.; Headley, K. L.; Herlien, R.; Kirkwood, W. J.; Matsumoto, G. I.; O'Reilly, T. C.; Salamy, K. A.; Scholfield, J.; Shane, F. F.; Walz, P. M.

    2012-12-01

    The MBARI deep-water FOCE experiment was deployed on the MARS cabled observatory in Monterey Bay on May 4th, 2011. It has been in continuous operation (excluding a few minor shore based power outages) ever since. During the fifteen months of deployment, we have been able to observe both the daily variation in pH in response to water mass movements associated with the semi-diurnal tides, internal waves and longer-term trends as a function of the seasonal variations in the water masses within the Monterey Bay Canyon. Our experimental site is located at 890 meters, just below the oxygen minimum for Monterey Bay, and we clearly see the anticipated inverse correlation between seawater temperature and pH. Daily variation in pH is on the order of 0.020-0.030 pH units with longer term trends adding an additional variation of similar magnitude. Instrumentation on this experiment included two CTDs with oxygen sensors (Sea-Bird 52). One CTD is mounted on the external FOCE framework to measure the background conditions, and one CTD is installed within the FOCE pH control area to monitor the experimentally manipulated conditions. In addition, 6 MBARI modified Sea-Bird 18 pH sensors were mounted on the FOCE apparatus. Four of these pH sensors monitored pH inside the experimental chamber and two monitored the external background seawater conditions. Although we originally intended to conduct several in situ CO2 enrichment experiments to study the impact of ocean acidification on the benthic biology and then recover the apparatus after one year, unanticipated changes in the ship schedule have left the FOCE experiment in place for nearly fifteen months at the time of this writing. Throughout this time period, all sensor data has been logged by the MBARI Shore-Side Data System (SSDS) resulting in the longest continuous record of high precision pH measurements in the intermediate water column. We present an analysis of the data obtained from this unique data set, and discuss our in

  2. USGS Tampa Bay Pilot Study

    Science.gov (United States)

    Yates, K.K.; Cronin, T. M.; Crane, M.; Hansen, M.; Nayeghandi, A.; Swarzenski, P.; Edgar, T.; Brooks, G.R.; Suthard, B.; Hine, A.; Locker, S.; Willard, D.A.; Hastings, D.; Flower, B.; Hollander, D.; Larson, R.A.; Smith, K.

    2007-01-01

    Many of the nation's estuaries have been environmentally stressed since the turn of the 20th century and will continue to be impacted in the future. Tampa Bay, one the Gulf of Mexico's largest estuaries, exemplifies the threats that our estuaries face (EPA Report 2001, Tampa Bay Estuary Program-Comprehensive Conservation and Management Plan (TBEP-CCMP)). More than 2 million people live in the Tampa Bay watershed, and the population constitutes to grow. Demand for freshwater resources, conversion of undeveloped areas to resident and industrial uses, increases in storm-water runoff, and increased air pollution from urban and industrial sources are some of the known human activities that impact Tampa Bay. Beginning on 2001, additional anthropogenic modifications began in Tampa Bat including construction of an underwater gas pipeline and a desalinization plant, expansion of existing ports, and increased freshwater withdrawal from three major tributaries to the bay. In January of 2001, the Tampa Bay Estuary Program (TBEP) and its partners identifies a critical need for participation from the U.S. Geological Survey (USGS) in providing multidisciplinary expertise and a regional-scale, integrated science approach to address complex scientific research issue and critical scientific information gaps that are necessary for continued restoration and preservation of Tampa Bay. Tampa Bay stakeholders identified several critical science gaps for which USGS expertise was needed (Yates et al. 2001). These critical science gaps fall under four topical categories (or system components): 1) water and sediment quality, 2) hydrodynamics, 3) geology and geomorphology, and 4) ecosystem structure and function. Scientists and resource managers participating in Tampa Bay studies recognize that it is no longer sufficient to simply examine each of these estuarine system components individually, Rather, the interrelation among system components must be understood to develop conceptual and

  3. EnviroAtlas - Green Bay, WI - Domestic Water Use per Day by U.S. Census Block Group

    Data.gov (United States)

    U.S. Environmental Protection Agency — As included in this EnviroAtlas dataset, the community level domestic water use is calculated using locally available water use data per capita in gallons of water...

  4. Nutrient and Sediment Reductions from Algal Flow-Way Technologies: Recommendations to the Chesapeake Bay Program's Water Quality Goal Implementation Team from the Algal Flow-Way Technologies BMP Expert Panel

    Science.gov (United States)

    The Chesapeake Stormwater Network hosted a workshop on July, 2012 to discuss the potential nutrient reductions from emerging stormwater technologies including algal flow-way technologies (AFTs). Workshop participants recommended the Chesapeake Bay Program’s Water Quality Goal Implementation Team(WQ...

  5. Length-weight relationship and condition factor in giant harpiosquillid Mantis shrimp, Harpiosquilla raphidea (Crustacea: Stomatopoda in Banten Bay waters, Indonesia

    Directory of Open Access Journals (Sweden)

    Mugi Mulyono

    2013-08-01

    Full Text Available Length-weight relationship of Harpiosquilla raphidea from Banten Bay waters was studied from 146 males and 186 females ranging from 38 to 354 and from 37 to 348 mm, respectively. The following equations were obtained Ln W = 5.164 + 2.478 Ln X (for males, Ln W = 5.333 + 2.596 Ln X (for females and Ln W = 5.264 + 2.549 Ln X, Ln X (pooled. The ‘b’ values (2.5497 found not near to 3 indicating allometric growth being matched up with the cube law. The ANCOVA indicated not much variation between the ‘b’ values for males and females. In general, the growth rate of the mantis shrimp H. raphidea almost the same or not much different from other mantis shrimp species of the order Stomatopoda.

  6. The cumulative impacts of repeated heavy rainfall, flooding and altered water quality on the high-latitude coral reefs of Hervey Bay, Queensland, Australia.

    Science.gov (United States)

    Butler, I R; Sommer, B; Zann, M; Zhao, J-X; Pandolfi, J M

    2015-07-15

    Terrestrial runoff and flooding have resulted in major impacts on coral communities worldwide, but we lack detailed understanding of flood plume conditions and their ecological effects. Over the course of repeated flooding between 2010 and 2013, we measured coral cover and water quality on the high-latitude coral reefs of Hervey Bay, Queensland, Australia. In 2013, salinity, total suspended solids, total nitrogen and total phosphorus were altered for up to six months post-flooding. Submarine groundwater caused hypo-saline conditions for a further four months. Despite the greater magnitude of flooding in 2013, declines in coral abundance (∼28%) from these floods were lower than the 2011 flood (∼40%), which occurred immediately after a decade of severe drought. There was an overall cumulative decrease of coral by ∼56% from 2010 to 2013. Our study highlights the need for local scale monitoring and research to facilitate informed management and conservation of catchments and marine environments.

  7. Trace Elements Contamination and Human Health Risk Assessment in Drinking Water from the Agricultural and Pastoral Areas of Bay County, Xinjiang, China.

    Science.gov (United States)

    Turdi, Muyessar; Yang, Linsheng

    2016-09-23

    Tap water samples were collected from 180 families in four agricultural (KYR: Keyir, KRW: Kariwak, YTR: Yatur, DW: Dawanqi) and two pastoral areas (B: Bulong and Y: Yangchang) in Bay County, Xinjiang, China, and levels of seven trace elements (Cd, Cr, As Ni, Pb, Zn, Se) were analyzed using inductively-coupled plasma mass spectrometry (ICP-MS) to assess potential health risks. Remarkable spatial variations of contamination were observed. Overall, the health risk was more severe for carcinogenic versus non-carcinogenic pollutants due to heavy metal. The risk index was greater for children overall (Cr > As > Cd and Zn > Se for carcinogenic and non-carcinogenic elements, respectively). The total risk index was greater in agricultural areas (DW > KYR > YTR > KRW > B > Y). Total risk indices were greater where well water was the source versus fountain water; for the latter, the total health risk index was greater versus glacier water. Main health risk factors were Cr and As in DW, KYR, YTR, KRW, and B, and Zn, Cr, and As in the Y region. Overall, total trace element-induced health risk (including for DW adults) was higher than acceptable (10(-6)) and lower than priority risk levels (10(-4)) (KYR, YTR, KRW, Y, and B). For DW children, total health risk reached 1.08 × 10(-4), higher than acceptable and priority risk levels (10(-4)).

  8. 杭州湾海域水污染演变及污染源分析%Evolution of Water Pollution and Analysis of Pollutant Source in Hangzhou Bay

    Institute of Scientific and Technical Information of China (English)

    顾骅珊

    2015-01-01

    以杭州湾海域水环境调查的相关数据为依据,研究杭州湾海域水污染演变及污染源情况。杭州湾海域常年以劣四类海水为主,水质状况极差,部分指标仍有恶化趋势。其主要超标污染物为无机氮和活性磷酸盐,化学需氧量浓度波动较大,但不是杭州湾水污染的主要威胁。从海域污染源来看,从富春江电站上游区域汇入的污染物占比最多;其次是杭州湾沿岸支流河道汇入的污染物;再次是从排海污水处理厂纳入的污染物。%Based on the related data from the survey on Hangzhou Bay water environment,the paper analyzed the process and the degree of the water deterioration and pollution in Hangzhou Bay.All year round, the water in Hangzhou bay contains mainly of four categories of poor sea water,some indexes of which are turn-ing worse.The main non-compliance pollutants are Inorganic nitrogen and Active phosphate in Hangzhou Bay. Although the concentration of chemical oxygen has fluctuations,it is not the main threat for the water pollution. With regard to the pollution source of the sea,the upstream region of Fuchun Rive power plant produced the largest proportion of pollutants;second,the pollutant coming from the tributaries along the coast of the Hang-zhou Bay;last,the pollutants from the wastewater treatment plant.

  9. Application of a Weighted Regression Model for Reporting Nutrient and Sediment Concentrations, Fluxes, and Trends in Concentration and Flux for the Chesapeake Bay Nontidal Water-Quality Monitoring Network, Results Through Water Year 2012

    Science.gov (United States)

    Chanat, Jeffrey G.; Moyer, Douglas L.; Blomquist, Joel D.; Hyer, Kenneth E.; Langland, Michael J.

    2016-01-13

    In the Chesapeake Bay watershed, estimated fluxes of nutrients and sediment from the bay’s nontidal tributaries into the estuary are the foundation of decision making to meet reductions prescribed by the Chesapeake Bay Total Maximum Daily Load (TMDL) and are often the basis for refining scientific understanding of the watershed-scale processes that influence the delivery of these constituents to the bay. Two regression-based flux and trend estimation models, ESTIMATOR and Weighted Regressions on Time, Discharge, and Season (WRTDS), were compared using data from 80 watersheds in the Chesapeake Bay Nontidal Water-Quality Monitoring Network (CBNTN). The watersheds range in size from 62 to 70,189 square kilometers and record lengths range from 6 to 28 years. ESTIMATOR is a constant-parameter model that estimates trends only in concentration; WRTDS uses variable parameters estimated with weighted regression, and estimates trends in both concentration and flux. WRTDS had greater explanatory power than ESTIMATOR, with the greatest degree of improvement evident for records longer than 25 years (30 stations; improvement in median model R2= 0.06 for total nitrogen, 0.08 for total phosphorus, and 0.05 for sediment) and the least degree of improvement for records of less than 10 years, for which the two models performed nearly equally. Flux bias statistics were comparable or lower (more favorable) for WRTDS for any record length; for 30 stations with records longer than 25 years, the greatest degree of improvement was evident for sediment (decrease of 0.17 in median statistic) and total phosphorus (decrease of 0.05). The overall between-station pattern in concentration trend direction and magnitude for all constituents was roughly similar for both models. A detailed case study revealed that trends in concentration estimated by WRTDS can operationally be viewed as a less-constrained equivalent to trends in concentration estimated by ESTIMATOR. Estimates of annual mean flow

  10. Seasonal variations of dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in the sea-surface microlayer and subsurface water of Jiaozhou Bay and its adjacent area

    Institute of Scientific and Technical Information of China (English)

    ZHANG Honghai; YANG Guipeng; LIU Chunying; LI Chenxuan

    2009-01-01

    The distributions of DMS and its precursor dimethylsulfoniopropionate, in both dissolved (DMSPd)and particulate fractions (DMSPp) were determined in the sea-surface microlayer and corresponding subsurface water of the Jiaozhou Bay, China and its adjacent area in May and August 2006.The concentrations of all these components showed a clear seasonal variation, with higher concentrations occurring in summer. This can be mainly attributed to the higher phytoplankton biomass observed in summer. Simultaneously, the enrichment extents of DMSPd and DMSPp in the microlayer also exhibited seasonal changes, with higher values in spring and lower ones in summer.Higher water temperature and stronger radiant intensity in summer can enhance their solubilityand photochemical reaction in the microlayer water, reducing their enrichment factors (the ratio of concentration in the microlayer to that in the corresponding subsurface water). A statistically significant relationship was found between the microlayer and subsurface water concentrations of DMS, DMSP and chlorophyll a, demonstrating that the biogenic materials in the microlayer come primarily from the underlying water. Moreover, our data show that the concentrations of DMSPp and DMS were significantly correlated with the levels of chlorophyll a, indicating that phytoplankton biomass might play an important role in controlling the distributions of biogenic sulfurs in the study area. The ratios of DMS/chlorophyll a and DMSPp/chlorophyll a varied little from spring to summer, suggesting that there was no obvious change in the proportion of DMSP producers in the phytoplankton community. The mean sea-to-air flux of DMS from the study area was estimated to be 5.70μmol/(m2·d),which highlights the effects of human impacts on DMS emision.

  11. Water resources of the Green Bay area, Wisconsin: G in Water resources of industrial regions: A summary of the source, occurrence, availability, and use of water in the area

    Science.gov (United States)

    Knowles, Doyle Blewer; Dreher, F.C.; Whetstone, George Walter

    1964-01-01

    The Green Bay area comprises an area of about 525 square miles in eastern Wisconsin at the south end of Green Bay. It includes the western three-fourths of Brown County and the eastern one-ninth of Outagamie County. In 1960, the population of the area was estimated at 124,000.

  12. Mercury and water-quality data from Rink Creek, Salmon River, and Good River, Glacier Bay National Park and Preserve, Alaska, November 2009-October 2011

    Science.gov (United States)

    Nagorski, Sonia A.; Neal, Edward G.; Brabets, Timothy P.

    2013-01-01

    Glacier Bay National Park and Preserve (GBNPP), Alaska, like many pristine high latitude areas, is exposed to atmospherically deposited contaminants such as mercury (Hg). Although the harmful effects of Hg are well established, information on this contaminant in southeast Alaska is scarce. Here, we assess the level of this contaminant in several aquatic components (water, sediments, and biological tissue) in three adjacent, small streams in GBNPP that drain contrasting landscapes but receive similar atmospheric inputs: Rink Creek, Salmon River, and Good River. Twenty water samples were collected from 2009 to 2011 and processed and analyzed for total mercury and methylmercury (filtered and particulate), and dissolved organic carbon quantity and quality. Ancillary stream water parameters (discharge, pH, dissolved oxygen, specific conductance, and temperature) were measured at the time of sampling. Major cations, anions, and nutrients were measured four times. In addition, total mercury was analyzed in streambed sediment in 2010 and in juvenile coho salmon and several taxa of benthic macroinvertebrates in the early summer of 2010 and 2011.

  13. Diffusive exchange of polycyclic aromatic hydrocarbons across the air-water interface of the Patapsco River, an urbanized subestuary of the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Bamford, H.A.; Offenberg, J.H.; Larsen, R.K.; Ko, F.C.; Baker, J.E. [Univ. of Maryland, Solomons, MD (United States)

    1999-07-01

    Air-water exchange fluxes of 13 polycyclic aromatic hydrocarbons (PAHs) were determined along a transect in the Patapsco River from the Inner Harbor of Baltimore, MD, to the mainstem of the northern Chesapeake Bay. Sampling took place at six sites during three sampling intensives (June 1996, February 1997, and July 1997) and at one site every ninth day between March 1997 and March 1998 to measure spatial, daily, and annual variability in the fluxes. The direction and magnitude of the daily fluxes of individual PAHs were strongly influenced by the wind speed and direction, by the air temperature, and by the highly variable PAH concentrations in the gas and dissolved phases. Individual fluxes ranged from 14,200 ng m{sup {minus}2} day{sup {minus}1} net volatilization of fluorene during high winds to 11,400 ng m{sup {minus}2} day{sup {minus}1} net absorption of phenanthrene when prevailing winds blowing from the northwest across the city of Baltimore elevated gaseous PAH concentrations over the water. The largest PAH volatilization fluxes occurred adjacent to the stormwater discharges, driven by elevated dissolved PAH concentrations in surface waters. Estimated annual volatilization fluxes ranged from 1.1 {micro}g m{sup {minus}2} yr{sup {minus}1} for chrysene to 800 {micro}g m{sup {minus}2} yr{sup {minus}1} for fluorene.

  14. 33 CFR 117.323 - Outer Clam Bay

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Outer Clam Bay 117.323 Section... DRAWBRIDGE OPERATION REGULATIONS Specific Requirements Florida § 117.323 Outer Clam Bay The drawspan of the Outer Clam Bay Boardwalk Drawbridge shall open on signal if at least 30 minutes advance notice is given....

  15. 78 FR 39608 - Safety Zone; Summer in the City Water Ski Show; Fox River, Green Bay, WI

    Science.gov (United States)

    2013-07-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Summer in the City Water Ski Show; Fox... restrict vessels from a portion of the Fox River due to a water ski show. This temporary safety zone is necessary to protect the surrounding public and vessels from the hazards associated with the water ski...

  16. 75 FR 17329 - Safety Zone; Big Bay Fourth of July Fireworks, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2010-04-06

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Big Bay Fourth of July Fireworks, San Diego Bay, San Diego, CA AGENCY: Coast Guard, DHS. ACTION: Notice of proposed rulemaking. SUMMARY: The Coast Guard proposes establishing a temporary safety zone on the navigable waters of the San Diego Bay in...

  17. The D/H Ratio of the Martian Water That Formed the Yellowknife Bay Mudstone Rocks Measured By the MSL-SAM Instrument

    Science.gov (United States)

    Mahaffy, P. R.; Webster, C. R.; Brunner, A.; McAdam, A.; Flesch, G.; Stern, J. C.; Eigenbrode, J. L.; Conrad, P. G.; Pavlov, A.; Malespin, C.; Atreya, S. K.; Blank, J. G.; Owen, T. C.

    2014-12-01

    Martian atmospheric loss processes change the isotopic composition of H, C, O, N, and Ar. Escape process to space enrich heavier isotopes in the atmosphere over geological time. The SAM instrument on the Curiosity rover has measured these isotopes in H2O, CO2, N2, and Ar multiple times over the course of the mission. In addition to this present record, volatiles extracted from ancient rocks such as the clays sampled in Yellowknife Bay mudstones of Gale crater may be able to reveal the isotopic composition of light elements much earlier in martian history. Small samples of mudstone rocks acquired by the Curiosity drill were analyzed by SAM for their volatile content. The SAM Tunable Laser Spectrometer (TLS) measured the D/H ratio in water and the Quadrupole Mass Spectrometer (QMS) determined the D/H ratio in hydrogen released from these samples by stepwise heating. Clay materials on Earth are known to contain water in several forms. Molecular water bound loosely in pore spaces may be removed by drying under ambient conditions. Water also may be adsorbed on the surface of clay mineral surfaces or reside in interlayer positions or within structural channels in the clays. Finally, clay minerals contain hydroxyl units bound structurally in the minerals that at elevated temperatures (>~ 450°C) produce water and hydrogen of dehydroxylation; this high-temperature component is most likely to reflect the isotopic composition of water (and atmosphere) present at the time of clay formation. We have designed and implemented a stepped extraction protocol to more precisely measure the D/H ratio in both the low and high temperature water in martian clays. The D/H in the high temperature water reflects the D/H of the water that formed these clay minerals. We will discuss the implications for water loss over the past 3+Ga and compare our findings with those of related martian meteorite studies. This research was supported by the National Aeronautics and Space Administration.

  18. Differences in the Effect of Coal Pile Runoff (Low pH, High Metal Concentrations) Versus Natural Carolina Bay Water (Low pH, Low Metal Concentrations) on Plant Condition and Associated Bacterial Epiphytes of Salvinia minima.

    Science.gov (United States)

    Lindell, A H; Tuckfield, R C; McArthur, J V

    2016-05-01

    Numerous wetlands and streams have been impacted by acid mine drainage (AMD) resulting in lowered pH and increased levels of toxic heavy metals. Remediation of these contaminated sites requires knowledge on the response of microbial communities (especially epiphytic) and aquatic plants to these altered environmental conditions. We examined the effect of coal pile runoff waters as an example of AMD in contrast to natural water from Carolina Bays with low pH and levels of metals on Salvinia minima, a non-native, metal accumulating plant and associated epiphytic bacteria. Treatments included water from two Carolina Bays, one AMD basin and Hoagland's Solution at two pH levels (natural and adjusted to 5.0-5.5). Using controlled replicated microcosms (N = 64) we determined that the combination of low pH and high metal concentrations has a significant negative impact (p epiphytes. Solution metal concentrations dropped indicating removal from solution by S. minima in all microcosms.

  19. Physico-chemical characterization of surface waters of the west coast of Algeria: Bay of Mostaganem and Cheliff estuary

    OpenAIRE

    Fatima Kies; Ahmed Kerkouf

    2014-01-01

    A follow-up in 2013 of the indicators of pollution (temperature, hydrogen potential, salinity, dissolved oxygen, ammonium, nitrites, nitrates, orthophosphates, ortho silicates, biological oxygen demand, chemical oxygen demand, suspended solids) in surface water was performed, in order to estimate the physicochemical quality of the west coast of Algeria. The results obtained revealed the existence of a water contamination by domestic and industrial waste water conveyed to the north by the Chel...

  20. Ground-water discharge and base-flow nitrate loads of nontidal streams, and their relation to a hydrogeomorphic classification of the Chesapeake Bay Watershed, middle Atlantic Coast

    Science.gov (United States)

    Bachman, L. Joseph; Lindsey, Bruce D.; Brakebill, John W.; Powars, David S.

    1998-01-01

    Existing data on base-flow and groundwater nitrate loads were compiled and analyzed to assess the significance of groundwater discharge as a source of the nitrate load to nontidal streams of the Chesapeake Bay watershed. These estimates were then related to hydrogeomorphic settings based on lithology and physiographic province to provide insight on the areal distribution of ground-water discharge. Base-flow nitrate load accounted for 26 to about 100 percent of total-flow nitrate load, with a median value of 56 percent, and it accounted for 17 to 80 percent of total-flow total-nitrogen load, with a median value of 48 percent. Hydrograph separations were conducted on continuous streamflow records from 276 gaging stations within the watershed. The values for base flow thus calculated were considered an estimate of ground-water discharge. The ratio of base flow to total flow provided an estimate of the relative importance of ground-water discharge within a basin. Base-flow nitrate loads, total-flow nitrate loads, and total-flow total-nitrogen loads were previously computed from water-quality and discharge measurements by use of a regression model. Base-flow nitrate loads were available from 78 stations, total-flow nitrate loads were available from 86 stations, and total-flow total-nitrogen loads were available for 48 stations. The percentage of base-flow nitrate load to total-flow nitrate load could be computed for 57 stations, whereas the percentage of base-flow nitrate load to totalflow total-nitrogen load could be computed for 36 stations. These loads were divided by the basin area to obtain yields, which were used to compare the nitrate discharge from basins of different sizes. The results indicate that ground-water discharge is a significant source of water and nitrate to the total streamflow and nitrate load. Base flow accounted for 16 to 92 percent of total streamflow at the 276 sampling sites, with a median value of 54 percent. It is estimated that of the 50

  1. Study on sea water intrusion into palaeochannels on south coastal plain of the Laizhou Bay by the Bohai Sea

    Institute of Scientific and Technical Information of China (English)

    韩美

    2003-01-01

    The palaeochannel evolution in the study region is divided into four stages by such meth-ods as 14C dating. Sea water intrusion through palaeochannels has been studied as a focal point.Palaeochannds are the main passageways through which the sea water intrudes at a higher speed,through many means and in a changeable dynamic state.

  2. 33 CFR 165.122 - Regulated Navigation Area: Navigable waters within Narragansett Bay and the Providence River...

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Regulated Navigation Area... SAFETY REGULATED NAVIGATION AREAS AND LIMITED ACCESS AREAS Specific Regulated Navigation Areas and Limited Access Areas First Coast Guard District § 165.122 Regulated Navigation Area: Navigable waters...

  3. 33 CFR 165.501 - Chesapeake Bay entrance and Hampton Roads, VA and adjacent waters-Regulated Navigation Area.

    Science.gov (United States)

    2010-07-01

    ... across the James River along the eastern side of U.S. Route 17 highway bridge, between Newport News and.... Thimble Shoal Channel consists of the waters bounded by a line connecting Thimble Shoal Channel Lighted... Auxiliary Channel consists of the waters in a rectangular area 450 feet wide adjacent to the north side...

  4. 76 FR 9709 - Water Quality Challenges in the San Francisco Bay/Sacramento-San Joaquin Delta Estuary

    Science.gov (United States)

    2011-02-22

    ... 2009 (Aug., 2009), available at http://www.water.ca.gov/news/newsreleases/2009/08122009martinmilligan2... Meeting on California Water Shortage (June 28, 2009), available at http://www.doi.gov/news/pressreleases... success if temperatures in the river channels upstream of Vernalis are unchanged? If so, how? How...

  5. Impact of Hurricane Irene on Vibrio vulnificus and Vibrio parahaemolyticus concentrations in surface water, sediment and cultured oysters in the Chesapeake Bay, Maryland, USA

    Directory of Open Access Journals (Sweden)

    Kristi S Shaw

    2014-05-01

    Full Text Available To determine if a storm event (i.e., high winds, large volumes of precipitation could alter concentrations of Vibrio vulnificus and Vibrio parahaemolyticus in aquacultured oysters (Crassostrea virginica and associated surface water and sediment, this study followed a sampling timeline before and after Hurricane Irene impacted the Chesapeake Bay estuary in late August 2011. Aquacultured oysters were sampled from two levels in the water column: surface 0.3 m and near-bottom just above the sediment. Concentrations of each Vibrio spp. and associated virulence genes were measured in oysters with a combination of real-time PCR and most probable number enrichment methods, and in sediment and surface water with real-time PCR. While concentration shifts of each Vibrio species were apparent post-storm, statistical tests indicated no significant change in concentration change for either Vibrio species by location (surface or near bottom oysters or date sampled (oyster tissue, surface water and sediment concentrations. V. vulnificus in oyster tissue was correlated with total suspended solids (r=0.41, p=0.04, and V. vulnificus in sediment was correlated with secchi depth (r=-0.93, p< 0.01, salinity (r=-0.46, p=0.02, tidal height (r=-0.45, p=0.03, and surface water V. vulnificus (r=0.98, p< 0.01. V. parahaemolyticus in oyster tissue did not correlate with environmental measurements, but V. parahaemolyticus in sediment and surface water correlated with several measurements including secchi depth (r=-0.48, p=0.02[sediment]; r=-0.97 p< 0.01[surface water] and tidal height (r=-0.96. p< 0.01[sediment], r=-0.59,p< 0.01 [surface water]. The concentrations of Vibrio spp. were higher in oysters relative to other studies (average V. vulnificus 4x105 MPN g-1, V. parahaemolyticus 1x105 MPN g-1, and virulence-associated genes were detected in most oyster samples. This study provides a first estimate of storm-related Vibrio density changes in oyster tissues, sediment and

  6. Reducing fluxes of faecal indicator compliance parameters to bathing waters from diffuse agricultural sources: the Brighouse Bay study, Scotland.

    Science.gov (United States)

    Kay, D; Aitken, M; Crowther, J; Dickson, I; Edwards, A C; Francis, C; Hopkins, M; Jeffrey, W; Kay, C; McDonald, A T; McDonald, D; Stapleton, C M; Watkins, J; Wilkinson, J; Wyer, M D

    2007-05-01

    The European Water Framework Directive requires the integrated management of point and diffuse pollution to achieve 'good' water quality in 'protected areas'. These include bathing waters, which are regulated using faecal indicator organisms as compliance parameters. Thus, for the first time, European regulators are faced with the control of faecal indicator fluxes from agricultural sources where these impact on bathing water compliance locations. Concurrently, reforms to the European Union (EU) Common Agricultural Policy offer scope for supporting on-farm measures producing environmental benefits through the new 'single farm payments' and the concept of 'cross-compliance'. This paper reports the first UK study involving remedial measures, principally stream bank fencing, designed to reduce faecal indicator fluxes at the catchment scale. Considerable reduction in faecal indicator flux was observed, but this was insufficient to ensure bathing water compliance with either Directive 76/160/EEC standards or new health-evidence-based criteria proposed by WHO and the European Commission.

  7. Historical methyl mercury in San Francisco Bay

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — San Francisco Bay, California is considered a mercury-impaired watershed. Elevated concentrations of mercury are found in water and sediment as well as fish and...

  8. San Antonio Bay 1986-1989

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The effect of salinity on utilization of shallow-water nursery habitats by aquatic fauna was assessed in San Antonio Bay, Texas. Overall, 272 samples were collected...

  9. Underwater Video Sites in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of Jobos Bay, Puerto Rico were mapped and characterized using visual interpretation...

  10. Underwater Video Transects in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Shallow-water (<30m) benthic habitat maps of the nearshore marine environment of Jobos Bay, Puerto Rico were mapped and characterized using visual interpretation...

  11. 33 CFR 100.904 - Celebrate Americafest, Green Bay, WI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Celebrate Americafest, Green Bay, WI. 100.904 Section 100.904 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND..., Green Bay, WI. (a) Regulated Area. A regulated area is established to include all waters of the...

  12. Particle backscattering variability in the coastal waters of Bay of Bengal: A case study along off Kakinada and Yanam Regions

    Digital Repository Service at National Institute of Oceanography (India)

    Latha, P.T.; Nagamani, P.V.; Rao, B.S.; Amarendra, P.; Rao, K.H.; Choudhury, S.B.; Dash, S.K.; Sarma, V.V.S.S.

    The distribution and variability of particulate back scattering coefficient (bbp) in the Godavari basin are reported for the first time using in situ measurements. A coastal cruise was conducted in the coastal waters Off Kakinada...

  13. Pawcatuck River and Narragansett Bay Drainage Basins. Water and Related Land Resources Study. Blackstone River Watershed. Appendices.

    Science.gov (United States)

    1981-08-01

    weee ir noww md Id I b Wock number) --The eight appendices to the main report provides descriptive material abbut the Blackstone River Basin. Appendices...PNB area). The team concentrated on water supply, water quality, recreation, marine management, flooding and erosion, minerals extraction and the...basin consists of gently rolling wooded hills. Peters River originates in Bellingham, Massachusetts, just north of Silver Lake. It flows southwesterly

  14. Isolation of enteroviruses from water, suspended solids, and sediments from Galveston Bay: survival of poliovirus and rotavirus adsorbed to sediments.

    OpenAIRE

    Rao, V. C.; Seidel, K M; Goyal, S M; Metcalf, T. G.; Melnick, J L

    1984-01-01

    The distribution and quantitation of enteroviruses among water, suspended solids, and compact sediments in a polluted estuary are described. Samples were collected sequentially from water, suspended solids, fluffy sediments (uppermost layer of bottom sediments), and compact sediment. A total of 103 samples were examined of which 27 (26%) were positive for virus. Polioviruses were recovered most often, followed by coxsackie B viruses and echoviruses 7 and 29. Virus was found most often attache...

  15. Evaluate Water Quality Condition of Jiaozhou Bay with Mathematical Models%利用数学模型评价胶州湾水质状况

    Institute of Scientific and Technical Information of China (English)

    李草青青

    2013-01-01

    依照2005年胶州湾水质的监测资料,采用两种数学模型方法---单因子指数法和模糊综合评价法分别进行水质现状的评价。通过计算得出结论:(1)胶州湾的东北部粪大肠菌群和无机氮超标,西北部无机氮严重超标,东南部粪大肠菌群超标,(2)采用熵权赋值法确定权重的模糊综合评价法的评价结果并不能体现水环境质量的实际情况,应该选取其他方法。%According to the monitoring data of water quality of Jiaozhou Bay in 2005 , we used two kinds of mathematical model method --- single factor index method and fuzzy comprehensive evaluation method to e-valuate water quality condition. The calculated conclusions were: (1) Fecal coliform bacteria and inorganic ni-trogen exceeded the standard in the northeast of Gulf of Jiaozhou, inorganic nitrogen seriously exceeded the standard in the northwest, fecal coliform bacteria exceed the standard in the southeast. ( 2 ) The evaluation results of fuzzy comprehensive evaluation method with the entropy weight assignment method can not reflect the actual situation of water environmental quality, so other methods should be chosen.

  16. Modeling Total Suspended Solids (TSS) Concentrations in Narragansett Bay.

    Science.gov (United States)

    This work covers mechanistic modeling of suspended particulates in estuarine systems with an application to Narragansett Bay, RI. Suspended particles directly affect water clarity and attenuate light in the water column. Water clarity affects both phytoplankton and submerged aqua...

  17. Four-year survey of dissolved/dispersed petroleum hydrocarbons on surface waters of Admiralty Bay, King George Island, Antarctica

    Directory of Open Access Journals (Sweden)

    Márcia Caruso Bícego

    2003-01-01

    Full Text Available Seawater from 8 stations in Admiralty Bay was systematically sampled during the summer of 1994, 1995, 1996 and 1997 and analyzed by spectrofluorimetry to measure dissolved/dispersed petroleum hydrocarbons (DDPHs. The purpose of this study was to detect some temporal and spatial changes in terms of oil contamination of the region. The results indicate low levels of oil pollution with relatively high concentrations near the research stations located in the study area. During the summers of 1995 and 1996 the average concentrations for individual stations were low and below of 0.50 ¼g.L-1. Summers of 1994 and 1997 had relatively higher average concentrations (up to 1.57 ¼g.L-1, mainly in front of Arctowski and Ferraz Research Stations.Amostras de água na Baía do Almirantado, Península Antártica, foram sistematicamente coletadas em 8 estações durante os verões de 1994 a 1997 onde foram analisados hidrocarbonetos do petróleo dispersos e dissolvidos por espectrofluorescência. O objetivo foi avaliar variações temporais e espaciais em termos de contaminação por óleo na região. Os resultados em geral indicam baixos níveis de poluição embora tenham sido verificadas algumas concentrações relativamente maiores nas proximidades das estações de pesquisa fixadas na região de estudo. Durante os anos de 1995 e 1996 a média das concentrações foram baixas e menores que 0,50 ¼g.L-1 para os pontos individuais. Os verões de 1994 e 1997 tiveram concentrações médias mais elevadas (até 1,57 ¼g.L-1, e os maiores valores foram nas proximidades das estações brasileira e polonesa.

  18. Distribution, Origin, and Realtions to Flow of Salty Ground Water Along the Western Margin of the Chesapeake Bay Impact Structure in Eastern Virginia

    Science.gov (United States)

    McFarland, R.; Bruce, S.

    2002-05-01

    The Chesapeake Bay impact structure closely coincides with parts of some aquifers in eastern Virginia that contain saltwater as much as 30 miles landward of the coast. The impact structure has thereby been inferred to play some role in controlling the presence of this "inland saltwater wedge", which formed under unstressed conditions prior to present-day ground-water withdrawals. That the impact severely disrupted the previously stratified sediments casts doubt on conceptualizations of a regionally contiguous, vertically layered system of aquifers and confining units. In addition, large and increasing ground-water withdrawals have resulted in continuing water-level declines and altered flow directions that create the potential for saltwater intrusion. Hence, the origin and emplacement of the saltwater must be known to predict its reaction to stresses being placed upon the flow system. Specific conductances and concentrations of chloride in ground water along the western margin of the impact structure reflect a transitional interface between freshwater to the west and seawater to the east that coincides aerially with the margin of the impact structure. Ratios of bromide to chloride and chlorine-36 to total chloride, and of stable hydrogen and oxygen isotopes, indicate chloride to have originated primarily from mixing of freshwater and seawater across the interface. In addition, deep ground water east of the interface having specific conductances which exceed that of seawater likely resulted from partial evaporation of seawater, either (1) in restricted coastal environments under arid conditions, (2) by rapid vaporization caused by the impact event, and (or) (3) by residual heat and associated hydrothermal activity following the impact. Mixing of freshwater and seawater has been theorized to take place in a "differential flushing" manner that left residual seawater to form the saltwater wedge. Seawater emplaced during inundation of the land surface persisted around

  19. GENOTOXICITY OF SHALLOW WATERS NEAR THE BRAZILIAN ANTARCTIC STATION "COMANDANTE FERRAZ" (EACF, ADMIRALTY BAY, KING GEORGE ISLAND, ANTARCTICA

    Directory of Open Access Journals (Sweden)

    Arthur José da Silva Rocha

    2015-03-01

    Full Text Available Series of biomonitoring surveys were undertaken weekly in February 2012 to investigate the genotoxicity of the shallow waters around the Brazilian Antarctic Station "Comandante Ferraz" (EACF. The comet assay was applied to assess the damage to the DNA of hemocytes of the crustacean amphipods Gondogeneia antarctica collected from shallow waters near the Fuel Tanks (FT and Sewage Treatment Outflow (STO of the research station, and compare it to the DNA damage of animals from Punta Plaza (PPL and Yellow Point (YP, natural sites far from the EACF defined as experimental controls. The damage to the DNA of hemocytes of G. antarctica was not significantly different between sites in the biomonitoring surveys I and II. In survey III, the damage to the DNA of animals captured in shallow waters near the Fuel Tanks (FT and Sewage Treatment Outflow (STO was significantly higher than that of the control site of Punta Plaza (PPL. In biomonitoring survey IV, a significant difference was detected only between the FT and PPL sites. Results demonstrated that the shallow waters in front of the station may be genotoxic and that the comet assay and hemocytes of G. antarctica are useful tools for assessing genotoxicity in biomonitoring studies of Antarctic marine coastal habitats.

  20. Bayes and empirical Bayes: do they merge?

    CERN Document Server

    Petrone, Sonia; Scricciolo, Catia

    2012-01-01

    Bayesian inference is attractive for its coherence and good frequentist properties. However, it is a common experience that eliciting a honest prior may be difficult and, in practice, people often take an {\\em empirical Bayes} approach, plugging empirical estimates of the prior hyperparameters into the posterior distribution. Even if not rigorously justified, the underlying idea is that, when the sample size is large, empirical Bayes leads to "similar" inferential answers. Yet, precise mathematical results seem to be missing. In this work, we give a more rigorous justification in terms of merging of Bayes and empirical Bayes posterior distributions. We consider two notions of merging: Bayesian weak merging and frequentist merging in total variation. Since weak merging is related to consistency, we provide sufficient conditions for consistency of empirical Bayes posteriors. Also, we show that, under regularity conditions, the empirical Bayes procedure asymptotically selects the value of the hyperparameter for ...

  1. Analysis of water-quality trends at two discharge stations; one within Big Cypress National Preserve and one near Biscayne Bay; southern Florida, 1966-94

    Science.gov (United States)

    Lietz, A.C.

    2000-01-01

    An analysis of water-quality trends was made at two U.S. Geological Survey daily discharge stations in southern Florida. The ESTREND computer program was the principal tool used for the determination of water-quality trends at the Miami Canal station west of Biscayne Bay in Miami and the Tamiami Canal station along U.S. Highway 41 in the Big Cypress National Preserve in Collier County. Variability in water quality caused by both seasonality and streamflow was compensated for by applying the nonparametric Seasonal Kendall trend test to unadjusted concentrations or flow-adjusted concentrations (residuals) determined from linear regression analysis. Concentrations of selected major inorganic constituents and physical characteristics; pH and dissolved oxygen; suspended sediment; nitrogen, phosphorus, and carbon species; trace metals; and bacteriological and biological characteristics were determined at the Miami and Tamiami Canal stations. Median and maximum concentrations of selected constituents were compared to the Florida Class III freshwater standards for recreation, propagation, and maintenance of a healthy, well-balanced population of fish and wildlife. The median concentrations of the water-quality constituents and characteristics generally were higher at the Miami Canal station than at the Tamiami Canal station. The maximum value for specific conductance at the Miami Canal station exceeded the State standard. The median and maximum concentrations for ammonia at the Miami and Tamiami Canal stations exceeded the State standard, whereas median dissolved-oxygen concentrations at both stations were below the State standard. Trend results were indicative of either improvement or deterioration in water quality with time. Improvement in water quality at the Miami Canal station was reflected by downward trends in suspended sediment (1987-94), turbidity, (1970-78), total ammonia (1971-94), total phosphorus (1987-94), barium (1978-94), iron (1969-94), and fecal coliform

  2. Oceanic Mixing Processes in Disko Bay-Ilulissat Icefjord System: Can We Quantify the Heat Loss from the Atlantic Water Layer?

    Science.gov (United States)

    Djoumna, G.; Holland, D. M.

    2014-12-01

    Ilulissat Icefjord (IIF) has been the site of few hydrographic observations. Recent hydrographic data from Disko Bay (DB) showed a significant warming from the below of the cold Polar Water entering DB from the mid-to-late 19901990s onward, and the sill at the fjord mouth prevented the modified West Greenland Irminger Waters (WGIW) to fill the IIF basin. Here we identify and attempt to quantify the fluxes associated with the small-scale processes that contribute to the upward diapycnal fluxes of heat, salt and from the modified WGIW to the surface-mixed layer using five years of summer data (2009 - 2013). The interaction between the WGIW and Egedesminde Dyb trough cutting across the continental shelf from the shelf break into DB creates the cold/warm layering of water masses which contribute to the formation of double diffusive thermohaline staircases. We found evidence of thermohaline staircase consists of series of sharp interfaces across which both TT and SS increase with depth separated by thick well-defined convective layers. We hypothesize that the warming of the PW layer in DB may have been caused by the upward heat fluxes from the AW driven double diffusive convection. Vertical heat fluxes estimated from laboratory-based flux laws for the diffusive regime of double diffusive convection were up to 0.20.2Wm-2^{-2}. The other major player responsible for the Atlantic water heat loss is shear instabilities in the internal wave and tides generated by barotropic tidal flow over the Egedesminde Dyb trough, the continental shelf and across the sill at the entrance of IIF. Using moored pressure data, we found that the fjord could be described as a wave-fjord during neap tide and turns into a tidal jet-fjord during spring tide, therefore a weak nonlinear response due to supercritical conditions with flow separation over the sill and a linear baroclinic tidal response due to the deeper right side of the sill could be expected. We found enhanced eddy diffusivity K

  3. Ground-water quality and discharge to Chincoteague and Sinepuxent Bays adjacent to Assateague Island National Seashore, Maryland

    Science.gov (United States)

    Dillow, Jonathan J.A.; Banks, William S.L.; Smigaj, Michael J.

    2002-01-01

    The U.S. Geological Survey, in cooperation with the Maryland Department of the Environment and the Wisconsin State Laboratory of Hygiene, conducted a study to characterize the occurrence and distribution of viral contamination in small (withdrawing less than 10,000 gallons per day) public water-supply wells screened in the shallow aquifer in the Piedmont Physiographic Province in Baltimore and Harford Counties, Maryland. Two hundred sixty-three small public water-supply wells were in operation in these counties during the spring of 2000. Ninety-one of these sites were selected for sampling using a methodology that distributed the samples evenly over the population and the spatial extent of the study area. Each site, and its potential susceptibility to microbiological contamination, was evaluated with regard to hole depth, casing interval, and open interval. Each site was evaluated using characteristics such as on-site geology and on-site land use.Samples were collected by pumping between 200 and 400 gallons of untreated well water through an electropositive cartridge filter. Water concentrates were subjected to cell-culture assay for the detection of culturable viruses and reverse-transcription polymerase chain reaction/gene probe assays to detect viral ribonucleic acid; grab samples were analyzed for somatic and male-specific coliphages, Bacteroides fragilis, Clostridium perfringens, enterococci, Escherichia coli, total coliforms, total oxidized nitrogen, nitrite, organic nitrogen, total phosphate, ortho-phosphate, calcium, magnesium, sodium, potas-sium, chloride, sulfate, iron, acid-neutralizing capacity, pH, specific conductance, temperature, and dissolved oxygen.One sample tested positive for the presence of the ribonucleic acid of rotavirus through poly-merase chain-reaction analysis. Twenty-nine per-cent of the samples (26 of 90) had bacterial con-tamination. About 7 percent of the samples (6 of 90) were contaminated with either male-specific coliphage

  4. Wind-enhanced resuspension in the shallow waters of South San Francisco Bay: Mechanisms and potential implications for cohesive sediment transport

    Science.gov (United States)

    Brand, Andreas; Lacy, Jessica R.; Hsu, Kevin; Hoover, Daniel; Gladding, Steve; Stacey, Mark T.

    2010-01-01

    We investigated the driving forces of sediment dynamics at the shoals in South San Francisco Bay. Two stations were deployed along a line perpendicular to a 14 m deep channel, 1000 and 2000 m from the middle of the channel. Station depths were 2.59 and 2.19 m below mean lower low water, respectively. We used acoustic Doppler velocimeters for the simultaneous determination of current velocities, turbulence, sediment concentration and fluxes. Maximum current shear velocities were 0.015 m s−1 at the station further from the channel (closer to the shore) and 0.02 m s−1 at the station closer to the channel. Peak wave-induced shear velocities exceeded 0.015 m s−1 at both stations. Maximum sediment concentrations were around 30 g m−3 during calm periods (root mean square wave height −3 and sediment fluxes were 5 times higher than in calm conditions (0.02 g m−2 s−1 versus >0.10 g m−2 s−1) at the station further from the channel 0.36 m above the bed. Closer to the channel, sediment concentrations and vertical fluxes due to wind wave resuspension were persistently lower (maximum concentrations around 50 g m−3 and maximum fluxes around 0.04 g m−2 s−1). Most resuspension events occurred during flood tides that followed wave events during low water. Although wave motions are able to resuspend sediment into the wave boundary layer at low tide, the observed large increases in sediment fluxes are due to the nonlinear interaction of wind waves and the tidal currents.

  5. Ichthyoplankton gut analysis with relevance to prey availability in the waters of Lamon Bay, northeastern Luzon, Philippines

    Science.gov (United States)

    Bollozos, I.; Yniguez, A. T.; Palermo, J. H.; Cabrera, O. C.; Villanoy, C. L.

    2013-12-01

    The waters in the eastern part of Luzon are highly influenced by the western boundary current system of the western Pacific brought about by the bifurcation of the North Equatorial Current into the Kuroshio and Mindanao Current. Eddies are formed with varying intensities as an effect of the ENSO cycle. Three spatial zones were identified according to prominent current movements and circulations observed during the summer 2011 and 2012 oceanographic cruises. These events also affect the productivity in the surrounding waters. Plankton samples were collected to determine the relative abundances of major groups representing three trophic levels. The abundance and composition of phyto- and zooplankton major groups slightly varied among the zones. Gut analysis of fish larvae was then conducted to determine potential prey preference and linked to the phyto- and zooplankton densities.

  6. Water Resources Improvement Study, Buttermilk Bay Channel, Bourne, Massachusetts; Small Navigation Project, Detailed Project Report, and Environmental Assessment.

    Science.gov (United States)

    1982-12-01

    would be restricted by the stage of the tide. The natural channel has a minimum depth of 3 feet at ralw over a width of 20 feet. This presents a very...project, we concur with your consistency determination. Sincerely, k Edward J. Reilly Assistant Secretary EJR/MEP:dc cc: John Hannon, Waterways Robert...Branch, Corps of Engineers, 424 Trapelo Road, Waltham 02154 John J. Hannon. Director, Division of Land & Water Use, Department of Environmental

  7. Development of Site-Specific Water Quality Criteria for the Arpa Harbor Wastewater Treatment Plant in Tipalao Bay, Guam

    Science.gov (United States)

    2016-07-01

    late April 2013 from various near-shore locations (water depth < 3 m) on the west coast of Guam, Marianas Islands, and held in outdoor tanks supplied... tanks associated with ships sanitary, the three bilge oily wastewater treatment units, the Fleet Industrial Service Center (FISC) fuel reclamation...Crustaceans, Holothurians and Sharks . FAO Species Identification Guide for Fishery Purposes. FAO, Rome, Italy. Carpenter, K. E. and V. H. Niem, Eds. 1999

  8. Spatio-temporal variability in hydro-chemical characteristics of coastal waters of Salimpur, Chittagong along the Bay of Bengal

    Directory of Open Access Journals (Sweden)

    Avijit Talukder

    2016-04-01

    Full Text Available Diverse seasonal characteristics of hydro-chemical parameters in the coastal zone are significantly related to aquaculture development. In this paper, general water quality condition derived from laboratory analysis from the coastal waters of Salimpur, Chittagong is presented. Samples were collected from onshore and offshore site of two adjacent coastal locations named as North Salimpur (experimental location and South Kattoli (control during a monsoon and a dry season spanning 2013-14. The spatio-temporal variability of studied parameters were found as air temperature 26.5-32.5 ˚C, water temperature 23-33 °C, pH 7.1-7.9, DO 4.29-7.11 mg/L, BOD 1.10-3.25 mg/L, salinity 1.6-21 ppt, EC 3.40-35.68 mS/cm, TDS 2.02-21.99 g/L, TSS 0.62-2.76 g/L, transparency 4.5-14 cm, precipitation 64-1992 mm, NO2-N 1.94-2.58 µg/L, PO4-P 0.45-1.84 µg/L, SiO3-Si 130.46-956.31 µg/L during investigation period. Average values of physicochemical parameters were found to be in compliance with standard guidelines. The ship breaking activities near experimental location possess negative impacts on local geomorphology, freshwater inputs, precipitation and aquatic environment as well. Moreover, wind driven forces, tidal action, wave characteristics and changes in monsoon pattern regulate the coastal processes. This research suggests the importance of regular monitoring to assess present status of water quality and future prospect of aquaculture in the Chittagong coastal zone.

  9. Nelson River and Hudson Bay

    Science.gov (United States)

    2002-01-01

    Rivers that empty into large bodies of water can have a significant impact on the thawing of nearshore winter ice. This true-color Moderate Resolution Imaging Spectroradiometer (MODIS) image from May 18, 2001, shows the Nelson River emptying spring runoff from the Manitoba province to the south into the southwestern corner of Canada's Hudson Bay. The warmer waters from more southern latitudes hasten melting of ice near the shore, though some still remained, perhaps because in shallow coastal waters, the ice could have been anchored to the bottom. High volumes of sediment in the runoff turned the inflow brown, and the rim of the retreating ice has taken on a dirty appearance even far to the east of the river's entrance into the Bay. The sediment would have further hastened the melting of the ice because its darker color would have absorbed more solar radiation than cleaner, whiter ice. Image courtesy Jacques Descloitres, MODIS Land Rapid Response Team at NASA GSFC

  10. Hydrochemistry of the Bay of Bengal: Possible reasons for a different water-column cycling of carbon and nitrogen from the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, C.K.; Naqvi, S.W.A.; DileepKumar, M.; Varaprasad, S.J.D; Jayakumar, D; George, M.D; Singbal, S.Y.S.

    A study on biogeochemical cycling in the western Bay of Bengal was undertaken during two seasons (pre-southwest monsoon and northeast monsoon of 1991). Relationships of the conservative tracers NO and PO with potential temperature (~f) are used...

  11. Influence of water allocation and freshwater inflow on oyster production: a hydrodynamic-oyster population model for Galveston Bay, Texas, USA.

    Science.gov (United States)

    Powell, Eric N; Klinck, John M; Hofmann, Eileen E; McManus, Margaret A

    2003-01-01

    A hydrodynamic-oyster population model was developed to assess the effect of changes in freshwater inflow on oyster populations in Galveston Bay, Texas, USA. The population model includes the effects of environmental conditions, predators, and the oyster parasite, Perkinsus marinus, on oyster populations. The hydrodynamic model includes the effects of wind stress, river runoff, tides, and oceanic exchange on the circulation of the bay. Simulations were run for low, mean, and high freshwater inflow conditions under the present (1993) hydrology and predicted hydrologies for 2024 and 2049 that include both changes in total freshwater inflow and diversions of freshwater from one primary drainage basin to another. Freshwater diversion to supply the Houston metropolitan area is predicted to negatively impact oyster production in Galveston Bay. Fecundity and larval survivorship both decline. Mortality from Perkinsus marinus increases, but to a lesser extent. A larger negative impact in 2049 relative to 2024 originates from the larger drop in fecundity under that hydrology. Changes in recruitment and mortality, resulting in lowered oyster abundance, occur because the bay volume available for mixing freshwater input from the San Jacinto and Buffalo Bayou drainage basins that drain metropolitan Houston is small in comparison to the volume of Trinity Bay that presently receives the bulk of the bay's freshwater inflow. A smaller volume for mixing results in salinities that decline more rapidly and to a greater extent under conditions of high freshwater discharge.Thus, the decline in oyster abundance results from a disequilibrium between geography and salinity brought about by freshwater diversion. Although the bay hydrology shifts, available hard substrate does not. The simulations stress the fact that it is not just the well-appreciated reduction in freshwater inflow that can result in decreased oyster production. Changing the location of freshwater inflow can also

  12. Monitoring the Northern San Francisco Bay Water Quality with Landsat-8. Nicholas B. Tufillaroa , and Curtiss O. Davisa. aOregon State University, Corvallis, OR, 97331, USA, nbt@coas.oregonstate.edu

    Science.gov (United States)

    Davis, C. O.; Tufillaro, N.

    2016-02-01

    Landsat-8's high spatial resolution ( 30 nm nominal), improved signal-to-noise (12bit digitizer) and expanded band set open up new applications for coastal and in-land waters. We use a recent ocean color processor for Landsat-8 created by Vanhellemont and Ruddick (RSE, 2015)to examine changes in the Northern San Francisco Bay, in particular looking for possiblechanges due to the on-going California drought. For instance, a temporary drought barrier to prevent salt water intrusion was placed during May of 2015 at West False River in the Sacramento-San Joaquin Delta. Using the new Landsat-8 ocean color products, we illustrate how to monitor changes in macro algae and plants (Sago pondweed (native), Curly pondweed (non-native)) in regions directly effected,such as the Franks Track region. Product maps using panchromatic enhancement ( 15 m resolution) andscene based atmospheric correction allow a detailed synoptic look every 16 days during theSpring, Summer, and Fall of 2015. This work is part of a larger NASA funded project aimed atimproving the modeling and predictive capabilities of the biogeochemical state for the San Francisco Bay(Davis, PI: Impacts of Population Growth on the San Francisco Bay and Delta Ecosystem, 2014-2017).

  13. 33 CFR 80.1132 - Estero-Morro Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Estero-Morro Bay, CA. 80.1132 Section 80.1132 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1132 Estero-Morro Bay, CA. A line drawn...

  14. 33 CFR 80.1112 - Newport Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Newport Bay, CA. 80.1112 Section 80.1112 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1112 Newport Bay, CA. A line drawn from...

  15. 33 CFR 80.1106 - Mission Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mission Bay, CA. 80.1106 Section 80.1106 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1106 Mission Bay, CA. A line drawn from...

  16. 33 CFR 80.1130 - San Luis Obispo Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false San Luis Obispo Bay, CA. 80.1130 Section 80.1130 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1130 San Luis Obispo Bay, CA. A line drawn...

  17. 33 CFR 80.1150 - Arcata-Humboldt Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Arcata-Humboldt Bay, CA. 80.1150 Section 80.1150 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1150 Arcata-Humboldt Bay, CA. A line drawn...

  18. 33 CFR 80.1420 - Mamala Bay, Oahu, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Mamala Bay, Oahu, HI. 80.1420 Section 80.1420 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1420 Mamala Bay, Oahu, HI. A line drawn...

  19. 33 CFR 80.1430 - Kaneohe Bay, Oahu, HI.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Kaneohe Bay, Oahu, HI. 80.1430 Section 80.1430 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Islands § 80.1430 Kaneohe Bay, Oahu, HI. A straight...

  20. 33 CFR 110.45 - Onset Bay, Mass.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Onset Bay, Mass. 110.45 Section 110.45 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Special Anchorage Areas § 110.45 Onset Bay, Mass. Northerly of a line extending...

  1. Impact of Wet Deposition of Black Carbon on Particle Dynamics in Surface Waters of Halong Bay, North Vietnam

    Science.gov (United States)

    Mari, X.; Guinot, B. P.; Thuoc, C. V.; Brune, J.; Lefebvre, J. P.; Raimbault, P.; Niggemann, J.; Dittmar, T.

    2016-02-01

    Black Carbon (BC) is an aerosol emitted during biomass burning and fossil fuel combustion. The atmospheric lifetime of Black Carbon (BC) ranges from a few days in rainy climates up to one month in dry regions, and on a global scale wet deposition of atmospheric BC accounts for about 80% of the BC input to the ocean. The rain-mediated input of BC to the ocean was studied in a coastal site located in a regional hotspot of atmospheric BC concentration, North Vietnam. We monitored changes in atmospheric and marine BC during a 24-h cycle impacted by a short and heavy rainfall event. During the rainfall event, atmospheric BC concentration decreased by a factor of 8 (i.e. from 5230 to 660 µg BC m-3). This cleaning of the air column was immediately followed by a significant increase (by a factor of 2 to 4) of particulate BC (PBC) and POC concentrations in the surface microlayer (SML) and at 1.5 m depth. In the SML, this event was also followed by a significant increase of DOC and dissolved BC (DBC) concentrations. Interestingly, the concentration of DOC decreased by >10% after the rainfall at 1.5 m depth, suggesting an adsorption of DOC onto sinking PBC. Concomitantly with the increase in particulate BC, nutrient concentrations increased by a factor of 2 in the SML, while no change was observed in the underlying water column. After the rainfall, the particle size spectra, measured along the water column with a LISST (Laser In-Situ Scattering and Transmissometry probe), changed in that the concentration of small particles (100 µm) increased. This alteration of the particle size spectra was restricted to a thin layer of about 20 cm thickness, probably corresponding to a BC-enriched layer adsorbing DOC and small particles, and stimulating aggregation during sinking from the surface to deeper water layers. The concentrations of POC, DOC, PBC, DBC and nutrients reached pre-rainfall levels 4 hours after the event.

  2. Pb distribution and translocation in Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The trends of distribution, translocation and seasonal change of heavy metal Pb were studied based on the surface and bottom water sampling in Jiaozhou Bay in 1979, and compared with those in 1990's. The results showed that the source of Pb in the bay was from wastewater and sewage in the east of Jiaozhou Bay from ocean vessels. Pb concentration was higher in spring and lower in summer and autumn, and remained stable through sedimentation in the bottom layer. The overall water quality was good in 1970's. Compared with the environmental monitoring data of 1995-1999, Pb pollution had become serious. Therefore, more efforts should be made to protect the bay from Pb pollution.

  3. [Microbiological and isotopic geochemical investigation of Lake Kislo-Sladkoe, a meromictic water body at the Kandalaksha Bay Shore (White Sea)].

    Science.gov (United States)

    Savvichev, A S; Lunina, O N; Rusanov, I I; Zakharova, E E; Veslopolova, E F; Ivanov, M V

    2014-01-01

    Microbiological, biogeochemical, and isotopic geochemical investigation of Lake Kislo-Sladkoe (Polusolenoe in early publications) at the Kandalaksha Bay shore (White Sea) was carried out in September 2010. Lake Kislo-Sladkoe was formed in the mid-1900s out of a sea gulf due to a coastal heave. At the time of investigation, the surface layer was saturated with oxygen, while near-bottom water contained sulfide (up to 32 mg/L). Total number of microorganisms was high (12.3 x 10(6) cells/mL on average). Light CO2 fixation exhibited two pronounced peaks. In the oxic zone, the highest rates of photosynthesis were detected at 1.0 and 2.0 m. The second, more pronounced peak of light CO2 fixation was associated with activity of anoxygenic phototrophic bacteria in the anoxic layer at the depth of 2.9 m (413 μg C L(-1) day(-1)). Green-colored green sulfur bacteria (GSB) predominated in the upper anoxic layer (2.7-2.9 m), their numbers being as high as 1.12 x 10(4) cells/mL, while brown-colored GSB predominated in the lower horizons. The rates of both sulfate reduction and methanogenesis peaked in the 2.9 m horizon (1690 μg S L(-1) day(-1) and 2.9 μL CH4 L(-1) day(-1)). The isotopic composition of dissolved methane from the near-bottom water layer (δ13C (CH4) = -87.76 per thousand) was significantly lighter than in the upper horizons (δ13C (CH4) = -77.95 per thousand). The most isotopically heavy methane (δ13C (CH4) = -72.61 per thousand) was retrieved from the depth of 2.9 m. The rate of methane oxidation peaked in the same horizon. As a result of these reactions, organic matter (OM) carbon of the 2.9 m horizon became lighter (-36.36 per thousand), while carbonate carbon became heavier (-7.56 per thousand). Thus, our results demonstrated that Lake Kislo-Sladkoe is a stratified meromictic lake with active microbial cycles of carbon and sulfur. Suspended matter in the water column was mostly of autochthonous origin. Anoxygenic photosynthesis coupled to utilization of

  4. Hydrology, phosphorus, and suspended solids in five agricultural streams in the Lower Fox River and Green Bay Watersheds, Wisconsin, Water Years 2004-06

    Science.gov (United States)

    Graczyk, David J.; Robertson, Dale M.; Baumgart, Paul D.; Fermanich, Kevin J.

    2011-01-01

    A 3-year study was conducted by the U.S. Geological Survey and the University of Wisconsin-Green Bay to characterize water quality in agricultural streams in the Fox/Wolf watershed in northeastern Wisconsin and provide information to assist in the calibration of a watershed model for the area. Streamflow, phosphorus, and suspended solids data were collected between October 1, 2003, and September 30, 2006, in five streams, including Apple Creek, Ashwaubenon Creek, Baird Creek, Duck Creek, and the East River. During this study, total annual precipitation was close to the 30-year normal of 29.12 inches. The 3-year mean streamflow was highest in the East River (113 ft3/s), followed by Duck Creek (58.2 ft3/s), Apple Creek (26.9 ft3/s), Baird Creek (12.8 ft3/s), and Ashwaubenon Creek (9.1 ft3/s). On a yield basis, during these three years, the East River had the highest flow (0.78 ft3/s/mi2), followed by Baird Creek (0.61 ft3/s/mi2), Apple Creek (0.59 ft3/s/mi2), Duck Creek (0.54 ft3/s/mi2), and Ashwaubenon Creek (0.46 ft3/s/mi2). The overall median total suspended solids (TSS) concentration was highest in Baird Creek (73.5 mg/L), followed by Apple and Ashwaubenon Creeks (65 mg/L), East River (40 mg/L), and Duck Creek (30 mg/L). The median total phosphorus (TP) concentration was highest in Ashwaubenon Creek (0.60 mg/L), followed by Baird Creek (0.47 mg/L), Apple Creek (0.37 mg/L), East River (0.26 mg/L), and Duck Creek (0.22 mg/L).

  5. Distribution of dissolved labile and particulate iron and copper in Terra Nova Bay polynya (Ross Sea, Antarctica) surface waters in relation to nutrients and phytoplankton growth

    Science.gov (United States)

    Rivaro, Paola; Ianni, Carmela; Massolo, Serena; Abelmoschi, M. Luisa; De Vittor, Cinzia; Frache, Roberto

    2011-05-01

    The distribution of the dissolved labile and of the particulate Fe and Cu together with dissolved oxygen, nutrients, chlorophyll a and total particulate matter was investigated in the surface waters of Terra Nova Bay polynya in mid-January 2003. The measurements were conducted within the framework of the Italian Climatic Long-term Interactions of the Mass balance in Antarctica (CLIMA) Project activities. The labile dissolved fraction was operationally defined by employing the chelating resin Chelex-100, which retains free and loosely bound trace metal species. The dissolved labile Fe ranges from below the detection limit (0.15 nM) to 3.71 nM, while the dissolved labile Cu from below the detection limit (0.10 nM) to 0.90 nM. The lowest concentrations for both metals were observed at 20 m depth (the shallowest depth for which metals were measured). The concentration of the particulate Fe was about 5 times higher than the dissolved Fe concentration, ranging from 0.56 to 24.83 nM with an average of 6.45 nM. The concentration of the particulate Cu ranged from 0.01 to 0.71 nM with an average of 0.17 nM. The values are in agreement with the previous data collected in the same area. We evaluated the role of the Fe and Cu as biolimiting metals. The N:dissolved labile Fe ratios (18,900-130,666) would or would not allow a complete nitrate removal, on the basis of the N:Fe requirement ratios that we calculated considering the N:P and the C:P ratios estimated for diatoms. This finding partially agrees with the Si:N ratio that we found (2.29). Moreover we considered a possible influence of the dissolved labile Cu on the Fe uptake process.

  6. Fall diets of red-breasted merganser (Mergus serrator) and walleye (Sander vitreus) in Sandusky Bay and adjacent waters of western Lake Erie

    Science.gov (United States)

    Bur, M.T.; Stapanian, M.A.; Bernhardt, G.; Turner, M.W.

    2008-01-01

    Although published studies indicate the contrary, there is concern among many sport anglers that migrating red-breasted mergansers (Mergus serrator) and other waterbirds pose a competitive threat to sport fish species such as walleye (Sander vitreus) in Lake Erie. We quantified the diet of autumn-migrant mergansers and walleye during 1998-2000 in Sandusky Bay and adjacent waters of western Lake Erie. We hypothesized that the diets of both predators would be similar in species composition, but because of different foraging ecologies their diets would differ markedly in size of prey consumed. In addition to predator samples, we used trawl data from the same general area as an index of prey availability. We found that mergansers fed almost exclusively on fish (nine species). Gizzard shad (Dorosoma cepedianum), emerald shiner (Notropis atherinoides) and round goby (Neogobius melanostomus) were consumed in the greatest numbers, most frequently and comprised the greatest biomass. Walleye fed exclusively on fish: gizzard shad, alewife (Alosa psuedoharengus) and emerald shiner were consumed in the greatest numbers, most frequently and comprised the greatest biomass. Diet overlap between mergansers and walleye was 67% by weight and 66% by species frequency. Mean total lengths of gizzard shad, emerald shiner and round goby found in walleye stomachs exceeded those captured in trawls by 47%, on average. Mean total lengths of gizzard shad, emerald shiner and round goby were greater in walleye stomachs than in merganser stomachs. Mean total lengths of emerald shiner and round goby were less in merganser stomachs than in trawls. Our results suggest that although the diets of walleye and mergansers overlapped considerably, mergansers generally consumed smaller fish than walleye. Given the abundance and diversity of prey species available, and the transient nature of mergansers on Lake Erie during migration, we conclude that competition for food between these species is minimal.

  7. Numerically modelling the sea-water and bubble plume dynamics found from the QICS project in Ardmucknish Bay

    Science.gov (United States)

    Dewar, M.; Sellami, N.; Chen, B.; Stahl, H.; Blackford, J.

    2013-12-01

    The QICS experiment carried out through spring 2012 investigated the nature and probability of leakage from a carbon dioxide (CO2) storage reservoir through a controlled CO2 release beneath a Scottish sea loch. This experiment allowed the measurement of the environmental impact, the development of various systems for monitoring, detecting and modelling leakage scenarios [1]. The ECO2 project involves the assessment of risk to the marine environment from sub-seabed CO2 storage sites [2] which means there is a strong link in aims for these two projects. Modelling the formation, dynamics and dissolution of CO2 gas bubbles in seawater allows the physiochemical impact on the marine environment to be predicted. This can be compared with data measured during the QICS experiment, proving the accuracy and viability of the models for full scale leakage scenarios. This study focuses on the role of bubble interactions on the plume formation and development; a two phase small scale plume model is improved by a sub-model of break up and coalescence of bubbles to simulate the bubble dynamics within a plume formation based on bubble measurements from the QICS experiment. The impact on the waters is shown through dissolution by the pCO2 and pH changes [3] and the model is validated against, and further developed utilising experimental measurements taken within the QICS project. [1] QICS, QICS: Quantifying and Monitoring Potential Ecosystem Impacts of Geological Carbon Storage. (Accessed 15.07.13), http://www.bgs.ac.uk/qics/home.html [2] ECO2, ECO2 - Sub-seabed CO2 Storage: Impact on Marine Ecosystems. (Accessed 16.07.13), http://www.eco2-project.eu [3] Dewar, M., et al. Small-scale modelling of the physiochemical impacts of CO2 leaked from sub-seabed reservoirs or pipe-lines with in the North Sea and surrounding waters. Mar. Pollut. Bull. (2013), http://dx.doi.org/10.1016/j.marpolbu l.2013.03.005

  8. 78 FR 66269 - Safety Zone, Sea World Fireworks; Mission Bay, San Diego, CA

    Science.gov (United States)

    2013-11-05

    ... establishing a temporary safety zone on the navigable waters of Mission Bay, south of Fiesta Island, for a... Bay, south of Fiesta Island. Persons and vessels are prohibited from entering into, transiting through...

  9. Dioxin toxin equivalents, PCBs, and PBDEs in eggs of avian wildlife of San Francisco Bay

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — San Francisco Bay (Bay) is considered an impaired waterbody under section 303 (d) of the Clean Water Act due to polychlorinated biphenyls (PCB) and 2, 3, 7,...

  10. Prospect of Oil/Gas Exploration in Beach Area of Bohai Bay Basin

    Institute of Scientific and Technical Information of China (English)

    Li Gansheng; Dou Lirong; Yuan Lingling; Rong Jiashu

    1997-01-01

    @@ Introduction Located in beach zone along Bohai Bay, the beach area of Bohai Bay basin is restricted between coastline and water depth of 5 m, stretching from Bayuquan to Huludao, Liaoning Province and Qinhuangdao, Hebei Province to Weihekou, Shandong Province.

  11. Virgin Islands: Coral Bay Watershed Management (A Former EPA CARE Project)

    Science.gov (United States)

    The Coral Bay Watershed Management is a recipient of the Level II CARE cooperative agreement to continue and expand its collective efforts to stop erosion, sediment, and storm-water pollution of Coral Bay, improve solid waste management,

  12. Survey of Nesting Osprey at Back Bay National Wildlife Refuge and False Cape State Park

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A survey of nesting Osprey (Pandion Haliaetus) was conducted during the nesting season of 1990. The survey was conducted in the bay waters of Back Bay National...

  13. Survey of Nesting Osprey at Back Bay National Wildlife Refuge and False Cape State Park

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A survey of nesting Osprey (Pandion Haliaetus) was conducted during the nesting season of 1989. The survey was conducted in the bay waters of Back Bay National...

  14. Composition and Distribution Characteristics of Organophosphorus Pesticides in the Sea Water of Sanggou Bay%桑沟湾水体中有机磷农药残留组成与分布

    Institute of Scientific and Technical Information of China (English)

    白红妍; 韩彬; 郑立; 杨东方; 王小如; 孙丕喜

    2012-01-01

    Organophosphorus pesticides (OPPs) of composition and distribution characteristics in the sea waters of Sanggou Bay have been studied by Gas Chromatography-Mass Speetrometry (GC-MS). Eight OPPs in the seawaters of Sanggou Bay were determined by using GC-MS with the external standard quantitative method in the Spring and Autumn of 2009. The range of concentration of ∑OPPs in the bay was 0.001 -0.265 μg/L with an average of 0. 061 μg/L. Six different types of OPPs were detected with the main pollutants being malathion and parathion. The distribution of OPPs from the survey in Sanggou Bay are presented in this paper. The results show that the concentration of OPPs is higher in the centre, lower far from the shore and decreasing from the outside to the inside of the bay at the surface water body, with the highest concentration at the bottom water body near the mouth of the bay in Spring. The concentration of OPPs increases from northwest and northeast outside of the bay to inside at the surface water body and increases from inside to outside at the bottom water body in Autumn. The results provide some references for the distribution characteristics of OPPs in this region.%采用气相色谱-质谱法定量测定桑沟湾海域水体中有机磷农药残留,分析了其组成与分布特征.2009年4月(春季)和10月(秋季)桑沟湾海域水体中8种有机磷农药的含量测定结果表明:桑沟湾有机磷农药的总浓度水平是春季小于秋季,有机磷农药的总浓度范围为0.001~0.265μg/L,均值为0.061μg/L.该海域水体中共检出6种有机磷农药,马拉硫磷和对硫磷是桑沟湾水体中主要的有机磷农药污染物.有机磷农药分布特征大致呈现春季表层水体中近岸高,离岸低,由湾口向湾内递减,底层水体中在湾口处浓度最高;秋季表层水体中由西北岸、东北湾口向湾中央渐增,底层水体中呈现由湾内向湾口递增的趋势.本研究提供的数据可为了解该海域

  15. Results of Back Bay Nutrient Sampling, April 1986 - March 1987

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To determine nutrient levels in Back Bay, water samples were collected monthly from April, 1986 through March, 1987. Surface water samples were collected at six...

  16. Tachibana Bay Electric Power Plant. Design and construction of pipe-laying works on the sea bottom for the industrial water; Tachibanawan hatsudensho. Kogyo yosui kaitei haikan koji no sekkei to seko

    Energy Technology Data Exchange (ETDEWEB)

    Shiono, A.; Tanaka, K. [Shikoku Electric Power Co., Inc., Takamatsu (Japan)

    1997-09-01

    At Kokatsu Island in the Bay of Tachibana, Anan City, Tokushima Prefecture, Tachibana Bay coal burning thermal electric power plants are now under construction. This is a joint venture of Shikoku electric Power Company and Dengen-kaihatsu (Power Resources Development Co.) with the objective of securing power supply in and after the year of 2000. The former plans one 700,000kW generator and the latter plans two 1.05 million kW generators totalling 2.8 million kW in terms of plant capacity. As for the above plants, the industrial water of 14,000m{sup 3} per day is required for various equipment including exhaust gas desulfurizers, etc. and the receiving and sending point of this industrial water is located at Ohgata Area, the northern opposite coast of this island. It is necessary to lay water pipes in the sea area from the above point up to Kokatsu Island, but this sea area lies within the important harbor designated for lanes and anchorages of vessels, hence traffic of vessels is heavy and restrictive conditions are many. Having studied various construction methods, the chain cutter simultaneous laying and burying method has been adopted. Three large calibre submarine water conveyance pipes, each of which is 250mm in inner diameter and about 2km long, have been built and the works have been completed at the end of June, 1997. 12 figs., 3 tabs.

  17. Influence of natural and anthropogenic factors on the water quality of the coastal waters around the South Andaman in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    VishnuRadhan, R.; Thresyamma, D.D.; Sarma, K.; George, G.; Shirodkar, P.V.; Vethamony, P.

    in the urbanized and industrialized areas. The discharged pollutants spread to different regions in the coast as domestic and industrial discharges open into the sea. Human habitats in the Pacific, Indian, and Caribbean Oceans substantially altered the island... program on Coastal Ocean Monitoring and Prediction System (COMAPS) for water quality monitoring and related issues have been operated along Indian coastal areas since 1991 under the programme on Integrated Coastal and Marine Area Management (ICMAM...

  18. Mercury distribution in the Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    The Jiaozhou Bay is a semi-enclosed bay, Qingdao, China. More than 10 rivers enter the bay, of which most take wastes from industrial and household discharges. According to historical seasonal investigations in May, August, November 1979, the content,distribution, and development of heavy metal mercury are analyzed as a historical reference. Water samples were taken from the surface and bottom. The results revealed clear seasonal and regional changes in both horizontal and vertical directions, and close relation with major discharging rivers and plankton production. The seawater was polluted more seriously in spring than in any other seasons.However, it was the cleanest in winter during which least waste was input with low plankton production. According to historical data,the state of mercury pollution in seawater was worsening in the period, and has been improving in recent years. Terrestrial contamination was the main reason for mercury pollution in the bay.

  19. Prospecção hidrobiológica da Baía de Sepetiba Color and transparence of waters of Sepetiba Bay, in Rio de Janeiro State

    Directory of Open Access Journals (Sweden)

    Lejeune P. H. de Oliveira

    1971-01-01

    green in the localities with blooms of the diatom Coscinodiscus. The central portion of the bay, 150 Km[squared] hole-green, full of larvae of shrimps Penaeus schmidti; some shoals of shrimps moves its pleopods and by displacement of botton with diatoms and reddish sediment produces a rust color spot in surface of waters seen by fishermen. The estuaries are Isabell color, and caramel. That is a preliminar survey, to future comparison, because to day Sepetiba Bay is not polluted. But futurelly, it will be polluted by an harbour for 3.000,000 tons of iron ore, and by a quay for cargo boats, and siderurgy mills, airports, and other industries. Several polluted waters of Guanabara Bay are black and asphalt color, and cub color. That colors are not found in Sepetiba Bay to day. In 1965, we do not find the "red waters" and "red tides" with blooms of dinoflagellates in Sepetiba Bay, that they are present sometimes in Guanabara Bay with mortalities of fishes. Sepetiba Bay is not biologic problem, to day, is not polluted. The fig. 3 shows a map of transparence of waters by the disc of Secchi and a relation is given of color and transparence, in Sepetiba: Forel color 5: transparence 2.8 m to 2.9 m; Forel n. 6: 2.0 m; Forel color n. 7: 1.0 m to 1.5 m. Moss green waters: 0.6 to 1.5 m; hellebore green waters: 0.9 to 1.5 m; emerald green waters: 2.0 m to 2.2 m; In Guanabara Bay, into the polluted Enseada de Inhaúma: asphalt color waters: 0.02 - 0.05 m; and in black waters: trasnparence of 1 cm. The extintion koeficient of light is indicated in explanation of the fig. 3.

  20. Sediment Pore Water Ammonium and Phosphate Concentrations in Choctawhatchee Bay as?Determined by the Diffusive Equilibration in Thin Films (DET) Technique

    Science.gov (United States)

    Choctawhatchee Bay (CB) is a large estuarine ecosystem in northwest Florida that provides quality of life and economic benefits to local residents. The CB watershed is largely forested, but with significant agriculture in its northern part and intense residential and commercial ...

  1. Water equivalent hydrogen estimates from the first 200 sols of Curiosity's traverse (Bradbury Landing to Yellowknife Bay): Results from the Dynamic Albedo of Neutrons (DAN) passive mode experiment

    Science.gov (United States)

    Tate, C. G.; Moersch, J.; Jun, I.; Ming, D. W.; Mitrofanov, I.; Litvak, M.; Behar, A.; Boynton, W. V.; Deflores, L.; Drake, D.; Ehresmann, B.; Fedosov, F.; Golovin, D.; Hardgrove, C.; Harshman, K.; Hassler, D. M.; Kozyrev, A. S.; Kuzmin, R.; Lisov, D.; Malakhov, A.; Milliken, R.; Mischna, M.; Mokrousov, M.; Nikiforov, S.; Sanin, A. B.; Starr, R.; Varenikov, A.; Vostrukhin, A.; Zeitlin, C.

    2015-12-01

    The Dynamic Albedo of Neutrons (DAN) experiment on the Mars Science Laboratory (MSL) rover Curiosity is designed to detect neutrons to determine hydrogen abundance within the subsurface of Mars (Mitrofanov, I.G. et al. [2012]. Space Sci. Rev. 170, 559-582. http://dx.doi.org/10.1007/s11214-012-9924-y; Litvak, M.L. et al. [2008]. Astrobiology 8, 605-613. http://dx.doi.org/10.1089/ast.2007.0157). While DAN has a pulsed neutron generator for active measurements, in passive mode it only measures the leakage spectrum of neutrons produced by the Multi-Mission Radioisotope Thermoelectric Generator (MMRTG) and Galactic Cosmic Rays (GCR). DAN passive measurements provide better spatial coverage than the active measurements because they can be acquired while the rover is moving. Here we compare DAN passive-mode data to models of the instrument's response to compositional differences in a homogeneous regolith in order to estimate the water equivalent hydrogen (WEH) content along the first 200 sols of Curiosity's traverse in Gale Crater, Mars. WEH content is shown to vary greatly along the traverse. These estimates range from 0.5 ± 0.1 wt.% to 3.9 ± 0.2 wt.% for fixed locations (usually overnight stops) investigated by the rover and 0.6 ± 0.2 wt.% to 7.6 ± 1.3 wt.% for areas that the rover has traversed while continuously acquiring DAN passive data between fixed locations. Estimates of WEH abundances at fixed locations based on passive mode data are in broad agreement with those estimated at the same locations using active mode data. Localized (meter-scale) anomalies in estimated WEH values from traverse measurements have no particular surface expression observable in co-located images. However at a much larger scale, the hummocky plains and bedded fractured units are shown to be distinct compositional units based on the hydrogen content derived from DAN passive measurements. DAN passive WEH estimates are also shown to be consistent with geologic models inferred from other

  2. Endocrine disrupter - estradiol - in Chesapeake Bay tributaries

    Energy Technology Data Exchange (ETDEWEB)

    Dorabawila, Nelum [University of Maryland Eastern Shore, Princess Anne, MD 21853 (United States); Gupta, Gian [University of Maryland Eastern Shore, Princess Anne, MD 21853 (United States)]. E-mail: gcgupta@umes.edu

    2005-04-11

    Exogenous chemicals that interfere with natural hormonal functions are considered endocrine disrupting chemicals (EDCs). Estradiol (17{beta}-estradiol or E2) is the most potent of all xenoestrogens. Induction of vitellogenin (VTG) production in male fish occurs at E2 concentrations as low as 1 ng l{sup -1}. E2 reaches aquatic systems mainly through sewage and animal waste disposal. Surface water samples from ponds, rivers (Wicomico, Manokin and Pocomoke), sewage treatment plants (STPs), and coastal bays (Assawoman, Monie, Chincoteague, and Tangier Sound - Chesapeake Bay) on the Eastern Shore of Maryland were analyzed for E2 using enzyme linked immuno-sorbent assay (ELISA). E2 concentrations in river waters varied between 1.9 and 6.0 ng l{sup -1}. Highest E2 concentrations in river waters were observed immediately downstream of STPs. E2 concentrations in all the coastal bays tested were 2.3-3.2 ng l{sup -1}.

  3. Discharge between San Antonio Bay and Aransas Bay, southern Gulf Coast, Texas, May-September 1999

    Science.gov (United States)

    East, Jeffery W.

    2001-01-01

    Along the Gulf Coast of Texas, many estuaries and bays are important habitat and nurseries for aquatic life. San Antonio Bay and Aransas Bay, located about 50 and 30 miles northeast, respectively, of Corpus Christi, are two important estuarine nurseries on the southern Gulf Coast of Texas (fig. 1). According to the Texas Parks and Wildlife Department, “Almost 80 percent of the seagrasses [along the Texas Gulf Coast] are located in the Laguna Madre, an estuary that begins just south of Corpus Christi Bay and runs southward 140 miles to South Padre Island. Most of the remaining seagrasses, about 45,000 acres, are located in the heavily traveled San Antonio, Aransas and Corpus Christi Bay areas” (Shook, 2000).Population growth has led to greater demands on water supplies in Texas. The Texas Water Development Board, the Texas Parks and Wildlife Department, and the Texas Natural Resource Conservation Commission have the cooperative task of determining inflows required to maintain the ecological health of the State’s streams, rivers, bays, and estuaries. To determine these inflow requirements, the three agencies collect data and conduct studies on the need for instream flows and freshwater/ saline water inflows to Texas estuaries.To assist in the determination of freshwater inflow requirements, the U.S. Geological Survey (USGS), in cooperation with the Texas Water Development Board, conducted a hydrographic survey of discharge (flow) between San Antonio Bay and Aransas Bay during the period May–September 1999. Automated instrumentation and acoustic technology were used to maximize the amount and quality of data that were collected, while minimizing personnel requirements. This report documents the discharge measured at two sites between the bays during May–September 1999 and describes the influences of meteorologic (wind and tidal) and hydrologic (freshwater inflow) conditions on discharge between the two bays. The movement of water between the bays is

  4. 33 CFR 110.75 - Corpus Christi Bay, Tex.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Corpus Christi Bay, Tex. 110.75... ANCHORAGE REGULATIONS Special Anchorage Areas § 110.75 Corpus Christi Bay, Tex. (a) South area. Southward of... said breakwater; and eastward of the Corpus Christi sea wall....

  5. Modelling of hydrodynamic circulation in Benoa Bay, Bali

    DEFF Research Database (Denmark)

    Ningsih, Nining Sari; Muchamad, Al Azhar

    2013-01-01

    A simulation of water level, velocity, salinity, and temperature in the Bay of Benoa has been carried out using a three-dimensional hydrodynamic Estuarine and Coastal Ocean Model incorporating a main characteristic of southward transport of the Indonesian throughflow at the offshore area of the bay...

  6. Characteristic mixing triangles in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Varkey, M.J.; Sastry, J.S.

    Temperature-salinity structures in the inner part of Bay of Bengal showed complete mixing processes in the upper bay, less than about 600 m can be characterisEd. by a mixing triangle constitutEd. by three characteristic water properties. In outer...

  7. Baseline surveys of Lac Bay benthic and fish communities, Bonaire

    NARCIS (Netherlands)

    Debrot, A.O.; Hylkema, A.; Vogelaar, W.; Meesters, H.W.G.; Engel, M.S.; Leon, R.; Prud'homme van Reine, W.F.; Nagelkerken, I.

    2012-01-01

    Lac Bay is a clear-water, 5 m deep shallow tropical lagoon of 7 km2 opening onto the wave and wind exposed east coast of the island of Bonaire, southern Caribbean. Over the last decades land reclamation by mangroves in Lac has been expanding the surface of turbid, saline backwaters into the bay at a

  8. 33 CFR 80.1144 - Bodega and Tomales Bay, CA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Bodega and Tomales Bay, CA. 80... INTERNATIONAL NAVIGATION RULES COLREGS DEMARCATION LINES Pacific Coast § 80.1144 Bodega and Tomales Bay, CA. (a... of Bodega Harbor North Breakwater to Bodega Harbor Entrance Light 1....

  9. Volcanisme, activité anthropique et circulation des masses océaniques : leur influence respective sur la distribution des populations d'ostracodes dans la baie de Kagoshima (île de Kyushu, Japon)Impact of volcanism, human activities, and water mass circulation on the distribution of ostracod populations in Kagoshima Bay (Kyushu Island, southern Japan)

    Science.gov (United States)

    Bodergat, Anne-Marie; Oki, Kimihiko; Ishizaki, Kunihiro; Rio, Michel

    2002-11-01

    The distribution of ostracod populations in Kagoshima Bay (Japan) is analysed with reference to different environmental parameters. The bay is an area of volcanic activity of Sakurajima volcano under the influence of the Kuroshio Current. Most of the Head environment is occupied by an acidic water mass. Numbers of individual and species decrease from the Mouth of the bay towards the Basin and Head environments. In this latter, acidic water mass has a drastic effect on ostracod populations, whereas volcanic ashes and domestic inputs are not hostile. Ostracod distribution is influenced by the quality and structure of water masses. To cite this article: A.-M. Bodergat et al., C. R. Geoscience 334 (2002) 1053-1059.

  10. 77 FR 54811 - Safety Zone; TriRock San Diego, San Diego Bay, San Diego, CA

    Science.gov (United States)

    2012-09-06

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; TriRock San Diego, San Diego Bay, San Diego... safety zone upon the navigable waters of the San Diego Bay, San Diego, CA, in support of a bay swim in San Diego Harbor. This safety zone is necessary to provide for the safety of the participants, crew...

  11. Organic matter remineralization predominates phosphorus cycling in the mid-Bay sediments in the Chesapeake Bay.

    Science.gov (United States)

    Joshi, Sunendra R; Kukkadapu, Ravi K; Burdige, David J; Bowden, Mark E; Sparks, Donald L; Jaisi, Deb P

    2015-05-19

    Chesapeake Bay, the largest and most productive estuary in the U.S., suffers from varying degrees of water quality issues fueled by both point and nonpoint nutrient sources. Restoration of the Bay is complicated by the multitude of nutrient sources, their variable inputs, and complex interaction between imported and regenerated nutrients. These complexities not only restrict formulation of effective restoration plans but also open up debates on accountability issues with nutrient loading. A detailed understanding of sediment phosphorus (P) dynamics provides information useful in identifying the exchange of dissolved constituents across the sediment-water interface as well as helps to better constrain the mechanisms and processes controlling the coupling between sediments and the overlying waters. Here we used phosphate oxygen isotope ratios (δ(18)O(P)) in concert with sediment chemistry, X-ray diffraction, and Mössbauer spectroscopy on sediments retrieved from an organic rich, sulfidic site in the mesohaline portion of the mid-Bay to identify sources and pathway of sedimentary P cycling and to infer potential feedbacks on bottom water hypoxia and surface water eutrophication. Authigenic phosphate isotope data suggest that the regeneration of inorganic P from organic matter degradation (remineralization) is the predominant, if not sole, pathway for authigenic P precipitation in the mid-Bay sediments. This indicates that the excess inorganic P generated by remineralization should have overwhelmed any pore water and/or bottom water because only a fraction of this precipitates as authigenic P. This is the first research that identifies the predominance of remineralization pathway and recycling of P within the Chesapeake Bay. Therefore, these results have significant implications on the current understanding of sediment P cycling and P exchange across the sediment-water interface in the Bay, particularly in terms of the sources and pathways of P that sustain hypoxia

  12. Salt Ponds, South San Francisco Bay

    Science.gov (United States)

    2002-01-01

    higher resolution 1000 pixel-wide image The red and green colors of the salt ponds in South San Francisco Bay are brilliant visual markers for astronauts. The STS-111 crew photographed the bay south of the San Mateo bridge in June, 2002. This photograph is timely because a large number of the salt ponds (more than 16,500 acres) that are owned by Cargill, Inc. will be sold in September for wetlands restoration-a restoration project second in size only to the Florida Everglades project. Rough boundaries of the areas to be restored are outlined on the image. Over the past century, more than 80% of San Francisco Bay's wetlands have been filled and developed or diked off for salt mining. San Francisco Bay has supported salt mining since 1854. Cargill has operated most of the bay's commercial salt ponds since 1978, and had already sold thousands of acres to the State of California and the Don Edwards National Wildlife Refuge. This new transaction will increase San Francisco Bay's existing tidal wetlands by 50%. The new wetlands, to be managed by the California Department of Fish and Game and the U.S. Fish and Wildlife Service, will join the Don Edwards National Wildlife Refuge, and provide valuable habitat for birds, fish and other wildlife. The wetlands will contribute to better water quality and flood control in the bay, and open up more coastline for public enjoyment. Additional information: Cargill Salt Ponds (PDF) Turning Salt Into Environmental Gold Salt Ponds on Way to Becoming Wetlands Historic Agreement Reached to Purchase San Francisco Bay Salt Ponds Astronaut photograph STS111-376-3 was provided by the Earth Sciences and Image Analysis Laboratory at Johnson Space Center. Additional images taken by astronauts and cosmonauts can be viewed at the NASA-JSC Gateway to Astronaut Photography of Earth

  13. eBay.com

    DEFF Research Database (Denmark)

    Engholm, Ida

    2014-01-01

    Celebrated as one of the leading and most valuable brands in the world, eBay has acquired iconic status on par with century-old brands such as Coca-Cola and Disney. The eBay logo is now synonymous with the world’s leading online auction website, and its design is associated with the company...

  14. Direct analysis of acetate and other volatile fatty acids in marine pore water by 2-dimensional ion chromatography-mass spectrometry (2D IC-MS) – A case study from Aarhus Bay (Denmark)

    DEFF Research Database (Denmark)

    Glombitza, Clemens; Lever, Mark; Jørgensen, Bo Barker

    Volatile fatty acids (VFA) such as formate, acetate, propionate and butyrate represent important intermediates in the anaerobic degradation of organic matter by microorganisms (Capone and Kiene, 1988). Knowledge on the concentrations and fluxes of these substrates, which are both end products...... and energy substrates of microbial metabolism is a key factor to determining energetic limits of sub-surface life and constraining the spatial extent of the so-called deep biosphere (Hoehler, 2007). Over the past 3 decades, numerous studies have quantified VFAs in marine pore water (e.g. Sansone and Martens...... µM. Analysis time is about 36 min per sample resulting in a sample throughput of more than 35 samples per day. In a first case study, we applied our novel procedure to pore water samples obtained from surface and sub-surface sediments of Aarhus Bay (Denmark). REFERENCES Albert, D.B., Martens, C...

  15. Phytoplankton composition and microcystin concentrations in open and closed bays of Lake Victoria, Tanzania

    Science.gov (United States)

    Mbonde, Athanasio S.; Sitoki, Lewis; Kurmayer, Rainer

    2017-01-01

    This study was carried out in order to investigate the spatial variation of algal toxin (microcystin) concentrations along the shoreline of Lake Victoria. A total of 16 nearshore stations differing in connectivity to the main lake basin were categorized as either closed bays (ratio of bay area to bay opening < 1) or open bays (ratio ≥ 1) and sampled during November and December 2009. Water samples were analyzed for total phosphorus (TP), chlorophyll a, phytoplankton community composition and concentrations of microcystin (MC). Open and closed bays were significantly different for phytoplankton abundance and composition: Average phytoplankton biovolume was higher for closed bays (45 mm3 L-1 ± 11 SE) than open bays (5 ± 2 mm3 L-1). Cyanobacterial biovolume (mainly Microcystis spp., Anabaena spp. and Planktolyngbya spp.) also was significantly higher in closed bays (82 ± 9% of total biovolume) than in open bays (44 ± 5%). In contrast, diatom biovolume was lower in closed bays (7 ± 1%) than in open bays (36 ± 6%). MCs were found only among sites from closed bays and concentrations ranged from 0.4 to 13 μg L-1 MC-LR equiv. and coincided with high abundance of Microcystis spp. It is concluded that the level of water exchange from individual bays to the main basin is an important factor influencing eutrophication and microcystin production in nearshore habitats of Lake Victoria. PMID:28077928

  16. Organic Matter Remineralization Predominates Phosphorus Cycling in the Mid-Bay Sediments in the Chesapeake Bay

    Energy Technology Data Exchange (ETDEWEB)

    Sunendra, Joshi R.; Kukkadapu, Ravi K.; Burdige, David J.; Bowden, Mark E.; Sparks, Donald L.; Jaisi, Deb P.

    2015-05-19

    The Chesapeake Bay, the largest and most productive estuary in the US, suffers from varying degrees of water quality issues fueled by both point and non–point source nutrient sources. Restoration of the bay is complicated by the multitude of nutrient sources, their variable inputs and hydrological conditions, and complex interacting factors including climate forcing. These complexities not only restrict formulation of effective restoration plans but also open up debates on accountability issues with nutrient loading. A detailed understanding of sediment phosphorus (P) dynamics enables one to identify the exchange of dissolved constituents across the sediment- water interface and aid to better constrain mechanisms and processes controlling the coupling between the sediments and the overlying waters. Here we used phosphate oxygen isotope ratios (δ18Op) in concert with sediment chemistry, XRD, and Mössbauer spectroscopy on the sediment retrieved from an organic rich, sulfidic site in the meso-haline portion of the mid-bay to identify sources and pathway of sedimentary P cycling and to infer potential feedback effect on bottom water hypoxia and surface water eutrophication. Isotope data indicate that the regeneration of inorganic P from organic matter degradation (remineralization) is the predominant, if not sole, pathway for authigenic P precipitation in the mid-bay sediments. We interpret that the excess inorganic P generated by remineralization should have overwhelmed any bottom-water and/or pore-water P derived from other sources or biogeochemical processes and exceeded saturation with respect to authigenic P precipitation. It is the first research that identifies the predominance of remineralization pathway against remobilization (coupled Fe-P cycling) pathway in the Chesapeake Bay. Therefore, these results are expected to have significant implications for the current understanding of P cycling and benthic-pelagic coupling in the bay, particularly on the

  17. 引水放流方式对太湖贡湖示范区水质的影响%Impact of Water Diversion Methods on Water Quality of the Demonstration Area in Gonghu Bay

    Institute of Scientific and Technical Information of China (English)

    杨阳; 钱新; 叶瑞; 高海龙; 刘喆

    2015-01-01

    A proportional physical model,in accordance with the demonstration area which locates in Gonghu Bay,Taihu Lake,was constructed to meet the demand of controlling both quality and quantity of water within that area for the state water special project.The effects of four diversion methods in the models would be studied in or-der to provide arguments for making decisions between diversion methods for the demonstration area.When con-ducting the study,the influences to the model′s flow field,assessed by measuring flow field data at five different cross sections,would be deemed as indicators for evaluating different diversion methods.Meanwhile,ink was cho-sen as a tracer and the spreading field changes of the tracer caused by different diversion methods would verify conclusions to the flow field.Therefore,an analysis could be conducted for the impact to water quality caused by the methods.The study provided a helpful reference for deciding the diversion method for the demonstration area.%基于国家水专项太湖贡湖湾示范区水质水量调控的需求,构建了示范区的等比例缩放实体模型。通过研究模型中4种不同调水方案的效果,为示范区调水技术的比较与选择提供决策依据。研究中,通过测定模型中5个断面的流场数据,判断引水方式对模型流场的影响,以此评价不同调水方案效果。同时以墨汁作为示踪剂,通过不同引水放流方式下示踪剂的扩散场变化,验证不同断面流速测定对整个区域流场判断的准确性,从而分析引水放流方式对水质的影响。

  18. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2013

    Science.gov (United States)

    Dyke, Jessica; Cain, Daniel J.; Thompson, Janet K.; Kleckner, Amy E.; Parcheso, Francis; Hornberger, Michelle I.; Luoma, Samuel N.

    2014-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January 2013 to December 2013. These data serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and M. petalum appear to have stabilized. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2013, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported previously. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se, were generally similar in timing and magnitude as those for Ag and Cu. In M. petalum, all observed elements showed annual maxima in January–February and minima in April, except for Zn, which was lowest in December. In sediments, annual maxima also occurred in January–February, and minima were measured in June and September. In 2013, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a

  19. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California, 2012

    Science.gov (United States)

    Dyke, Jessica; Thompson, Janet K.; Cain, Daniel J.; Kleckner, Amy E.; Parcheso, Francis; Luoma, Samuel N.; Hornberger, Michelle I.

    2013-01-01

    Trace-metal concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica), clam reproductive activity, and benthic macroinvertebrate community structure were investigated in a mudflat 1 kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay, Calif. This report includes the data collected by U.S. Geological Survey (USGS) scientists for the period January to December 2012. These data serve as the basis for the City of Palo Alto’s Near-Field Receiving Water Monitoring Program, initiated in 1994. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations in sediment and in M. petalum appear to have stabilized. Data for other metals, including chromium (Cr), mercury (Hg), nickel (Ni), selenium (Se), and zinc (Zn), have been collected since 1994. Over this period, concentrations of these elements have remained relatively constant, aside from seasonal variation that is common to all elements. In 2012, concentrations of Ag and Cu in M. petalum varied seasonally in response to a combination of site-specific metal exposures and annual growth and reproduction, as reported for previous time periods. Seasonal patterns for other elements, including Cr, Ni, Zn, Hg, and Se were generally similar in timing and magnitude as those for Ag and Cu. In 2012, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record. This record suggests that regional-scale factors now largely control sedimentary and bioavailable concentrations of Ag and Cu, as well as other elements of regulatory interest, at the Palo Alto site. Analyses of the benthic community structure of a mudflat in South San Francisco Bay over a 39-year period show that changes in the community have occurred concurrent with reduced concentrations of metals in the sediment and in the tissues of the biosentinel clam, M. petalum, from the same area

  20. Near-field receiving water monitoring of trace metals and a benthic community near the Palo Alto Regional Water Quality Control Plant in south San Francisco Bay, California; 2009

    Science.gov (United States)

    Dyke, Jessica; Parchaso, Janet K.; Thompson, Janet K.; Cain, Daniel J.; Luoma, Samuel N.; Hornberger, Michelle I.

    2010-01-01

    Results reported herein include trace element concentrations in sediment and in the clam Macoma petalum (formerly reported as Macoma balthica (Cohen and Carlton, 1995)), clam reproductive activity, and benthic macroinvertebrate community structure for a mudflat one kilometer south of the discharge of the Palo Alto Regional Water Quality Control Plant (PARWQCP) in South San Francisco Bay. This report includes data collected for the period January 2009 to December 2009 and extends a critical long-term biogeochemical record dating back to 1974. These data serve as the basis for the City of Palo Alto's Near-Field Receiving Water Monitoring Program, initiated in 1994. In 2009, metal concentrations in both sediments and clam tissue were among the lowest concentrations on record and consistent with results observed since 1991. Following significant reductions in the late 1980s, silver (Ag) and copper (Cu) concentrations appeared to have stabilized. Annual mean concentrations have fluctuated modestly (2-4 fold) in a nondirectional manner. Data for other metals, including chromium, mercury, nickel, selenium, vanadium, and zinc, have been collected since 1994. Over this period, concentrations of these elements, which more likely reflect regional inputs and systemwide processes, have remained relatively constant, aside from typical seasonal variation that is common to all elements. Within years, the winter months (January-March) generally exhibit maximum concentrations, with a decline to annual minima in spring through fall. Mercury (Hg) in sediments and M. petalum were comparable to concentrations observed in 2008 and were generally consistent with data from previous years. Selenium (Se) concentrations in sediment varied among years and showed no sustained temporal trend. In 2009, sedimentary Se concentrations declined from the record high concentrations observed in 2008 to concentrations that were among the lowest on record. Selenium in M. petalum was unchanged from 2008

  1. Emplacement of subaerial pahoehoe lava sheet flows into water: 1990 Kūpaianaha flow of Kilauea volcano at Kaimū Bay, Hawai`i

    Science.gov (United States)

    Umino, Susumu; Nonaka, Miyuki; Kauahikaua, James P.

    2006-01-01

    Episode 48 of the ongoing eruption of Kilauea, Hawai`i, began in July 1986 and continuously extruded lava for the next 5.5 years from a low shield, Kūpaianaha. The flows in March 1990 headed for Kalapana and inundated the entire town under 15–25 m of lava by the end of August. As the flows advanced eastward, they entered into Kaimū Bay, replacing it with a plain of lava that extends 300 m beyond the original shoreline. The focus of our study is the period from August 1 to October 31, 1990, when the lava buried almost 406,820 m2 of the 5-m deep bay. When lava encountered the sea, it flowed along the shoreline as a narrow primary lobe up to 400 m long and 100 m wide, which in turn inflated to a thickness of 5–6 m. The flow direction of the primary lobes was controlled by the submerged delta below the lavas and by damming up lavas fed at low extrusion rates. Breakout flows through circumferential and axial inflation cracks on the inflating primary lobes formed smaller secondary lobes, burying the lows between the primary lobes and hiding their original outlines. Inflated flow lobes eventually ruptured at proximal and/or distal ends as well as mid-points between the two ends, feeding new primary lobes which were emplaced along and on the shore side of the previously inflated lobes. The flow lobes mapped with the aid of aerial photographs were correlated with daily observations of the growing flow field, and 30 primary flow lobes were dated. Excluding the two repose periods that intervened while the bay was filled, enlargement of the flow field took place at a rate of 2,440–22,640 square meters per day in the bay. Lobe thickness was estimated to be up to 11 m on the basis of cross sections of selected lobes measured using optical measurement tools, measuring tape and hand level. The total flow-lobe volume added in the bay during August 1–October 31 was approximately 3.95 million m3, giving an average supply rate of 0.86 m3/s.

  2. Impact of upwelling events on the sea water carbonate chemistry and dissolved oxygen concentration in the Gulf of Papagayo (Culebra Bay, Costa Rica: Implications for coral reefs

    Directory of Open Access Journals (Sweden)

    Tim Rixen

    2012-04-01

    Full Text Available The Gulf of Papagayo, Pacific coast of Costa Rica, is one of the three seasonal upwelling areas of Mesoamerica. In April 2009, a 29-hour experiment was carried out at the pier of the Marina Papagayo, Culebra Bay. We determined sea surface temperature (SST, dissolved oxygen concentration, salinity, pH, and the partial pressure of CO2 (pCO2. The aragonite saturation state (Ωa as well as the other parameters of the marine carbonate system such as the total dissolved inorganic carbon (DIC and the total alkalinity (TA were calculated based on the measured pH and the pCO2. The entrainment of subsurface waters raised the pCO2 up to 645 µatm. SSTs, dissolved oxygen concentrations decreased form 26.4 to 23.7°C and from 228 to 144 µmol l-1. Ωa dropped down to values of 2.1. Although these changes are assumed to reduce the coral growth, the main reef building coral species within the region (Pocillopora spp. and Pavona clavus reveal growth rates exceeding those measured at other sites in the eastern tropical Pacific. This implies that the negative impact of upwelling on coral growth might be overcompensated by an enhanced energy supply caused by the high density of food and nutrients and more favorable condition for coral growth during the non-upwelling season.El Golfo de Papagayo, costa Pacífica de Costa Rica, es una de las tres regiones de afloramiento estacional de Mesoamérica. Las características físicas y químicas del agua que aflora no habían sido estudiadas. Durante 29 horas en Abril 2009, se estudiaron la temperatura superficial del mar (TSM, la concentración de oxígeno disuelto, salinidad, pH y la presión parcial de CO2 (pCO2, en la Marina Papagayo, Bahía Culebra. Con base en las mediciones de pH y pCO2 se calculó el estado de saturación de la aragonita (Ω y otros parámetros del sistema de carbonatos como lo es el carbono orgánico disuelto (COD y la alcalinidad total (AT. Los resultados indican que el arrastre por convecci

  3. 胶州湾湾口海域海水淡化取水水质分析%Analysis on the quality of sea water at the entrance of Jiaozhou Bay for desalination

    Institute of Scientific and Technical Information of China (English)

    周斌; 姜宏川; 褚加志; 刘伟; 殷学博; 刘淑君

    2012-01-01

    The water quality is an important factor affecting the cost of desalination. By analyzing the data of sea water quality at the entrance of Jiaozhou Bay obtained in May, August and November of 2007, the results showed that most factors, including pH, DO, COD, Cu, Zn, Petroleum Hydrocarbon and PO43-P, fit the standard of Grade Ⅱ of Sea Water Quality Standards, except DIN at some coastal stations. The contents of SS and TDS were low. The contents of Ca2+ and Mg2+ were lower than those in the Bay. This area can be used as the intake source of desalination. The water pretreatment process should pay close attention to the effect caused by Calcium, Magnesium, Iron and Manganese.%取水水质是影响海水淡化成本的重要因素之一,根据2007年5月、8月和11月3个航次的调查数据,对胶州湾湾口海域海水水质进行了分析.结果表明,除个别近岸站DIN超过二类海水水质标准外,pH、DO、COD、Cu、Zn、油类、PO43--P等指标均符合二类海水水质标准,SS、TDS含量较低,Ca2+、Mg2+含量低于湾内,该区海水可作为淡化取水水源,预处理工艺中应关注钙、镁、铁和锰的影响.

  4. Surface layer temperature inversion in the Bay of Bengal

    Science.gov (United States)

    Thadathil, Pankajakshan; Gopalakrishna, V. V.; Muraleedharan, P. M.; Reddy, G. V.; Araligidad, Nilesh; Shenoy, Shrikant

    2002-10-01

    Surface layer temperature inversion occurring in the Bay of Bengal has been addressed. Hydrographic data archived in the Indian Oceanographic Data Center are used to understand various aspects of the temperature inversion of surface layer in the Bay of Bengal, such as occurrence time, characteristics, stability, inter-annual variability and generating mechanisms. Spatially organized temperature inversion occurs in the coastal waters of the western and northeastern Bay during winter (November-February). Although the inversion in the northeastern Bay is sustained until February (with remnants seen even in March), in the western Bay it becomes less organized in January and almost disappears by February. Inversion is confined to the fresh water induced seasonal halocline of the surface layer. Inversions of large temperature difference (of the order of 1.6-2.4°C) and thin layer thickness (10-20 m) are located adjacent to major fresh water inputs from the Ganges, Brahmaputra, Irrawaddy, Krishna and Godavari rivers. The inversion is stable with a mean stability of 3600×10 -8 m -1. Inter-annual variability of the inversion is significantly high and it is caused by the inter-annual variability of fresh water flux and surface cooling in the northern Bay. Fresh water flux leads the occurrence process in association with surface heat flux and advection. The leading role of fresh water flux is understood from the observation that the two occurrence regions of inversion (the western and northeastern Bay) have proximity to the two low salinity (with values about 28-29‰) zones. In the western Bay, the East India Coastal Current brings less saline and cold water from the head of the Bay to the south-west Bay, where it advects over warm, saline water, promoting temperature inversion in this region in association with the surface heat loss. For inversion occurring in the northeastern Bay (where the surface water gains heat from atmosphere), surface advection of the less saline

  5. Runup of tsunami waves in U-shaped bays

    CERN Document Server

    Didenkulova, Ira

    2010-01-01

    The problem of tsunami wave shoaling and runup in U-shaped bays (such as fjords) and underwater canyons is studied in the framework of shallow water theory. The wave shoaling in bays, when the depth varies smoothly along the channel axis, is studied with the use of asymptotic approach. In this case a weak reflection provides significant shoaling effects. The existence of traveling (progressive) waves, propagating in bays, when the water depth changes significantly along the channel axis, is studied. It is shown that traveling waves do exist for certain bay bathymetry configurations and may propagate over large distances without reflection. The tsunami runup in such bays is significantly larger than for a plane beach.

  6. Spatial variability of trace metals and inorganic nutrients in surface waters of Todos Santos Bay, México in the summer of 2005 during a red tide algal bloom.

    Science.gov (United States)

    Lares, M L; Marinone, S G; Rivera-Duarte, I; Beck, A; Sañudo-Wilhelmy, S

    2009-05-01

    Dissolved and particulate metals (Ag, Cd, Co, Cu, Ni, and Zn) and nutrients (PO(4), NO(3), and H(4)SiO(4)) were measured in Todos Santos Bay (TSB) in August 2005. Two sources producing local gradients were identified: one from a dredge discharge area (DDA) and another south of the port and a creek. The average concentrations of dissolved Cd and Zn (1.3 and 15.6 nM, respectively) were higher by one order of magnitude than the surrounding Pacific waters, even during upwelling, and it is attributed to the presence of a widespread and long-lasting red tide coupled with some degree of local pollution. A clear spatial gradient (10 to 6 pM), from coast to offshore, of dissolved Ag was evident, indicating the influence of anthropogenic inputs. The particulate fraction of all metals, except Cu, showed a factor of ~3 decrease in concentrations from the DDA to the interior of the bay. The metal distributions were related to the bay's circulation by means of a numerical model that shows a basically surface-wind-driven offshore current with subsurface compensation currents toward the coast. Additionally, the model shows strong vertical currents over the DDA. Principal component analysis revealed three possible processes that could be influencing the metal concentrations within TSB: anthropogenic inputs (Cd, Ag, and Co), biological proceses (NO(3), Zn, and Cu), and upwelling and mixing (PO(4), H(4)SiO(4), Cd, and Ni). The most striking finding of this study was the extremely high Cd concentrations, which have been only reported in highly contaminated areas. As there was a strong red tide, it is hypothesized that the dinoflagellates are assimilating the Cd, which is rapidly remineralized and being concentrated on the stratified surface layers.

  7. Fine Sediment Resuspension Dynamics in Moreton Bay

    Institute of Scientific and Technical Information of China (English)

    YOU Zai-jin; YIN Bao-shu

    2007-01-01

    A comprehensive field study has been undertaken to investigate sediment resuspension dynamics in the Moreton Bay, a large semi-enclosed bay situated in South East Queensland, Australia. An instrumented tripod, which housed three current meters, three OBS sensors and one underwater video camera, was used to collect the field data on tides, currents, waves and suspended sediment concentrations at four sites (Sites 1, 2, 4, and 5) in the bay. Site 1 was located at the main entrance, Site 2 at the central bay in deep water, and Sites 4 and 5 at two small bays in shallow water. The bed sediment was fine sand (d50=0.2 mm) at Site 1, and cohesive sediment at the other three sites. Based on the collected field data, it is found that the dominant driving forces for sediment resuspension are a combination of ocean swell and tidal currents at Site 1, tidal currents at Site 2, and wind-waves at Sites 4 and 5. The critical bed shear stress for cohesive sediment resuspension is determined as 0.079 Pa in unidirectional flow at Site 2, and 0.076 Pa in wave-induced oscillatory flow at Site 5.

  8. Distribution of polycyclic aromatic hydrocarbons (PAHs) in sewage effluent, continental and coastal waters from the Northwestern Mediterrean Sea: Comparison between two contrasted catchment areas (Marseilles Bay and Vermeille coast)

    Science.gov (United States)

    Guigue, Catherine; Ferretto, Nicolas; Méjanelle, Laurence; Tedetti, Marc; Ghiglione, Jean-François; Goutx, Madeleine

    2014-05-01

    Polycyclic aromatic hydrocarbons (PAHs) were analysed from sewage treatment plant waters and surface waters collected in continental (rivers), harbour and off-shore marine sites from Marseilles Bay and Vermeille coastal areas between 2009 and 2013 (Northwestern Mediterranean Sea, France). After collection, water samples were first filtered on glass fiber filters, then PAHs from the dissolved phase were extracted using liquid-liquid or solid phase extraction (SPE) methods, while those from particles were treated according to Bligh and Dyer method. After a possible purification step, extracts were analysed by gas chromatography coupled to mass spectrometry (GC-MS). Regardless of the study area, dissolved and particulate PAH (18 parents + alkylated homologues) concentration averages were 150.2 ± 140.5 ng l-1and 39.4 ± 71.2 ng l-1, respectively. Interestingly, the concentration in dissolved PAHs was on average 3.8 higher than the concentration in particulate PAHs. In addition, a gradient of PAH concentrations was observed from coastal waters with the highest values in harbours and outlet sewage effluents and the lowest values in off-shore marine waters. Intermediate concentrations were recorded in continental waters. In the Marseilles Bay, dissolved PAH concentrations were significantly higher and associated to increased signatures of unburned and combusted fossil fuels, mainly from heating, during the cold period (November-April). In contrast, unburned petroleum signature dominated in the warm period (May-October), emphasizing the intense shipping traffic and urban/industrial activities occurring in one of the largest Mediterranean harbour and city. Conversely, in the Vermeille coastal waters, dissolved PAH concentrations were higher during the warm period when particulate PAHs displayed the lowest concentrations, suggesting a seasonal related partition between dissolved and particulate PAHs. In addition, in the Vermeille coastal waters, PAHs were dominated by

  9. Salinity and Flow Monitoring in the San Francisco Bay Delta

    Science.gov (United States)

    This report describes the utility and approximate cost of expanding the salinity water quality monitoring network along the axis of the San Francisco Estuary from Suisun Bay to Rio Vista on the Sacramento River.

  10. 33 CFR 100.116 - Swim Buzzards Bay Day, New Bedford, MA.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Swim Buzzards Bay Day, New Bedford, MA. 100.116 Section 100.116 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY REGATTAS AND MARINE PARADES SAFETY OF LIFE ON NAVIGABLE WATERS § 100.116 Swim Buzzards Bay...

  11. North Inlet-Winyah Bay National Estuarine Research Reserve's (NERR) Estuarine Surface Water Nutrient, Suspended Sediment, and Chlorophyll a Data for the North Inlet and Winyah Bay Estuaries, Georgetown, South Carolina: 1993-2001

    Data.gov (United States)

    Baruch Institute for Marine and Coastal Sciences, Univ of South Carolina — A one 1000 ml (one Liter) water sample was collected every 20 days at 2 hour and 4 minute intervals for 2 complete tidal cycles (26 hours) with an ISCO automated...

  12. Management case study: Tampa Bay, Florida

    Science.gov (United States)

    Morrison, G.; Greening, H.S.; Yates, K.K.

    2012-01-01

    Tampa Bay, Florida,USA, is a shallow,subtropical estuary that experienced severe cultural eutrophication between the 1940s and 1980s, a period when the human population of its watershed quadrupled. In response, citizen action led to the formation of a public- and private-sector partnership (the Tampa Bay Estuary Program), which adopted a number of management objectives to support the restoration and protection of the bay’s living resources. These included numeric chlorophyll a and water-clarity targets, as well as long-term goals addressing the spatial extent of sea grasses and other selected habitat types, to support estuarine-dependent faunal guilds.

  13. CHARACTERISTICS OF WATER TEMPERATURE DISTRIBUTION IN XIANGXI BAY OF THE THREE GORGES RESERVOIR%三峡水库香溪河库湾水温分布特性研究

    Institute of Scientific and Technical Information of China (English)

    余真真; 王玲玲; 戴会超; 成高峰

    2011-01-01

    建立三维水温数学模型,对2007年三峡水库香溪河库湾及部分库首江段的水温分布特性进行了数值研究.根据计算区域的特点,模型采用贴体网格系统,并充分考虑水体与外界的热交换、人流、出流等因素,利用实测资料率定相关参数后进行模拟,结果表明:(1)香溪河库湾属于季节性水温分层型水体,分层期会有温跃层的出现;但在水平方向上水温差异较小,全年水温在11.1~29.14℃变化.(2)库区干流由于水体紊动作用强,模拟时段2007年全年没有发生水温分层现象.(3)库湾在水温分层期间,表层的水温普遍高于干流,底层局部水温则低于干流,香溪河口存在水平及立面环流与潜流现象,呈现极为复杂的三维流动特性.研究结果可为三峡库区生态环境安全管理提供科学依据.%In this study,a three-dimensional model of water temperature has been developed, and the characteristics of water temperature distribution in Xiangxi Tributary Bay and part of mainstream of Three Gorges Reservoir in the year of 2007 were studied using numerical simulation method. The body-fitted grid system was applied to the computational domain,the heat exchange between the water body and the outside, the inflow,and the outflow were took into account fully,the measured data were used to calibrate the water temperature model. Simulation was undertaken for one year and the results showed that the Xiangxi Bay was the water body of seasonal temperature stratification, and the thermocline could be observed during stratification. However,the temperature difference was smaller in horizontal plane. The annual water temperature changed from 11.1 ℃ to 29.14℃. The phenomenon of water temperature stratification in the mainstream did not occur in 2007 because of strong turbulence. The temperature of surface water in the Xiangxi Bay was generally higher than the mainstream in the stratified period,but the temperature of bottom

  14. Biscayne Bay Alongshore Epifauna

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Field studies to characterize the alongshore epifauna (shrimp, crabs, echinoderms, and small fishes) along the western shore of southern Biscayne Bay were started in...

  15. Bathymetry in Jobos Bay

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This image represents a 4x4 meter resolution bathymetric surface for Jobos Bay, Puerto Rico (in NAD83 UTM 19 North). The depth values are in meters referenced to the...

  16. Hammond Bay Biological Station

    Data.gov (United States)

    Federal Laboratory Consortium — Hammond Bay Biological Station (HBBS), located near Millersburg, Michigan, is a field station of the USGS Great Lakes Science Center (GLSC). HBBS was established by...

  17. Chesapeake Bay Tributary Strategies

    Science.gov (United States)

    Chesapeake Bay Tributary Strategies were developed by the seven watershed jurisdictions and outlined the river basin-specific implementation activities to reduce nutrient and sediment pollutant loads from point and nonpoint sources.

  18. Humboldt Bay Orthoimages

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set consists of 0.5-meter pixel resolution, four band orthoimages covering the Humboldt Bay area. An orthoimage is remotely sensed image data in which...

  19. eBay.com

    DEFF Research Database (Denmark)

    Engholm, Ida

    2014-01-01

    Celebrated as one of the leading and most valuable brands in the world, eBay has acquired iconic status on par with century-old brands such as Coca-Cola and Disney. The eBay logo is now synonymous with the world’s leading online auction website, and its design is associated with the company......’s purpose: selling millions of goods, some of which are ‘designer’ items and some of which are considered design icons....

  20. 莱州湾南岸潍坊北部平原区咸水入侵动态变化分析%Analysis on Dynamic Changes of Salt Water Intrusion in Northern Weibei Plain in South Laizhou Bay

    Institute of Scientific and Technical Information of China (English)

    管清花; 陈学群; 张婧

    2014-01-01

    In this paper,setting northern Weifang plain in southern Laizhou Bay as the typical research area,geo-logical background of salt water formation and distribution have been described.Through water chemistry method, characteristics of water chemistry change of underground brine and the change of saltwater instrusion caused by hu-man activities in northern Weifang plain have been analyzed.Main causes of salt water intrusion has been analyzed as well.%以莱州湾南岸潍坊北部平原地区为典型研究区,阐述了咸水体形成的成因背景与分布特征。通过水化学分析的方法,分析了潍北平原地下水水化学变化特征,及人工开采导致咸水入侵的变化,并分析了咸水入侵的主要成因。

  1. Mapping Oyster Reef Habitats in Mobile Bay

    Science.gov (United States)

    Bolte, Danielle

    2011-01-01

    Oyster reefs around the world are declining rapidly, and although they haven t received as much attention as coral reefs, they are just as important to their local ecosystems and economies. Oyster reefs provide habitats for many species of fish, invertebrates, and crustaceans, as well as the next generations of oysters. Oysters are also harvested from many of these reefs and are an important segment of many local economies, including that of Mobile Bay, where oysters rank in the top five commercial marine species both by landed weight and by dollar value. Although the remaining Mobile Bay oyster reefs are some of the least degraded in the world, projected climate change could have dramatic effects on the health of these important ecosystems. The viability of oyster reefs depends on water depth and temperature, appropriate pH and salinity levels, and the amount of dissolved oxygen in the water. Projected increases in sea level, changes in precipitation and runoff patterns, and changes in pH resulting from increases in the amount of carbon dioxide dissolved in the oceans could all affect the viability of oyster reefs in the future. Human activities such as dredging and unsustainable harvesting practices are also adversely impacting the oyster reefs. Fortunately, several projects are already under way to help rebuild or support existing or previously existing oyster reefs. The success of these projects will depend on the local effects of climate change on the current and potential habitats and man s ability to recognize and halt unsustainable harvesting practices. As the extent and health of the reefs changes, it will have impacts on the Mobile Bay ecosystem and economy, changing the resources available to the people who live there and to the rest of the country, since Mobile Bay is an important national source of seafood. This project identified potential climate change impacts on the oyster reefs of Mobile Bay, including the possible addition of newly viable

  2. Characterizing the influence of tide on the physico-chemical parameters and nutrient variability in the coastal surface water of the northern Bay of Bengal during the winter season

    Institute of Scientific and Technical Information of China (English)

    SOURAV Das; ABHRA Chanda; SANDIP Giri; ANIRBAN Akhand; SUGATA Hazra

    2015-01-01

    The spatial distribution of physico-chemical parameters (sea surface temperature (SST), pH, sea surface salinity (SSS), dissolved oxygen (DO) and Secchi depth) along with filterable nutrients (dissolved inorganic nitrate (DIN), dissolved inorganic phosphate (DIP) and reactive silicate (DSi)) are measured in the winter months of November, December, January and February for four consecutive years from 2009–2010 to 2012–2013 on the shallow continental shelf (<20 m bathymetry) of the coastal waters (up to 18 km away from shoreline) of the northern Bay of Bengal (nBoB) during the highest high tide (HHT) and lowest low tide (LLT) hours for the first time. The variability of the coastal biogeochemical environment is assessed during the HHT and LLT hours and for this purpose, seawater samples are collected from seven different locations of a transect in the coastal region. Physico-chemical parameters (except SST) show significant difference in magnitude during the HHT and LLT hours respectively. pH, SSS and DO are found to increase in the HHT hours and vice-versa. The data reveal that during the LLT hours, a relative increase of freshwater input in the nBoB can have elevated the nutrient concentration compared with that observed during the HHT hours. The ratio of nutrient concentration is found to deviate significantly from the Redfield ratio. The abundance of DIP is much higher compared with that of DIN and DSi. The anthropogenic sources of DIP from the upstream flow (especially the domestic effluent of several metropolises) can be mainly attributed behind such an observation. In order to characterize and establish the trend of such variation in such an important bio-climatic region, long-term and systematic ecosystem monitoring in the coastal water of the nBoB northern Bay of Bengal should be carried out throughout the year.

  3. Integrating science and resource management in Tampa Bay, Florida

    Science.gov (United States)

    Yates, Kimberly K.; Greening, Holly; Morrison, Gerold

    2011-01-01

    Tampa Bay is recognized internationally for its remarkable progress towards recovery since it was pronounced "dead" in the late 1970s. Due to significant efforts by local governments, industries and private citizens throughout the watershed, water clarity in Tampa Bay is now equal to what it was in 1950, when population in the watershed was less than one-quarter of what it is today. Seagrass extent has increased by more than 8,000 acres since the mid-1980s, and fish and wildlife populations are increasing. Central to this successful turn-around has been the Tampa Bay resource management community's long-term commitment to development and implementation of strong science-based management strategies. Research institutions and agencies, including Eckerd College, the Florida Wildlife Commission Fish and Wildlife Research Institute, Mote Marine Laboratory, National Oceanic and Atmospheric Administration, the Southwest Florida Water Management District, University of South Florida, U.S. Environmental Protection Agency, U.S. Geological Survey, local and State governments, and private companies contribute significantly to the scientific basis of our understanding of Tampa Bay's structure and ecological function. Resource management agencies, including the Tampa Bay Regional Planning Council's Agency on Bay Management, the Southwest Florida Water Management District's Surface Water Improvement and Management Program, and the Tampa Bay Estuary Program, depend upon this scientific basis to develop and implement regional adaptive management programs. The importance of integrating science with management has become fully recognized by scientists and managers throughout the region, State and Nation. Scientific studies conducted in Tampa Bay over the past 10–15 years are increasingly diverse and complex, and resource management programs reflect our increased knowledge of geology, hydrology and hydrodynamics, ecology and restoration techniques. However, a synthesis of this

  4. Using remote sensing technique for analyzing temporal changes of seagrass beds by human impacts in waters of Cam Ranh Bay, Vietnam

    Science.gov (United States)

    Minh Thu, Phan; Hoang Son, Tong Phuoc; Komatsu, Teruhisa

    2012-10-01

    Seagrass beds/meadows are very productive ecosystems with high biodiversities. However, they have been degraded under high pressures of human activities. Combining depth-invariance index and ground-truthing, distribution of seagrass beds in Cam Ranh Bay was identified by analyses of multi-remote sensing images such as LANDSAT, SPOT and ALOS AVNIR-2. Although coverage of seagrass meadows was1178 ha, the seagrass meadows were being degraded by illegal fishing methods, aquaculture and discharges from industries and living domestics. The reducing ratio of seagrass coverage has been increased in recent years. While the depth-invariance index method would help to detect the areas of seagrass beds, this method requires combination of field trip and absorption library methods to increase classification accuracy. Final maps of the status and changes of seagrass beds could help to integrate the sustainable development of economy with protection of natural resources.

  5. Module bay with directed flow

    Science.gov (United States)

    Torczynski, John R.

    2001-02-27

    A module bay requires less cleanroom airflow. A shaped gas inlet passage can allow cleanroom air into the module bay with flow velocity preferentially directed toward contaminant rich portions of a processing module in the module bay. Preferential gas flow direction can more efficiently purge contaminants from appropriate portions of the module bay, allowing a reduced cleanroom air flow rate for contaminant removal. A shelf extending from an air inlet slit in one wall of a module bay can direct air flowing therethrough toward contaminant-rich portions of the module bay, such as a junction between a lid and base of a processing module.

  6. Status of Bay of Bengal: An Ecological Point of View

    Directory of Open Access Journals (Sweden)

    Pai IK

    2010-04-01

    Full Text Available The marine resources are a major source of food, a reservoir of minerals, major suppliers of oxygen, regulator of climate. It is also an ultimate dumping ground for the mounting burden of human waste material. Due to unchecked anthropogenic activity in recent years, the physico-chemical and biological status of the marine environments have changed significantly. This has resulted in the changing environmental scenario of the world. The Bay of Bengal, is one of the largest Bay in the world known to receive large flow of sediments from several rivers and other water bodies from India, Bhutan, Bangladesh, Myanmar, Indonesia etc., Many of these rivers bring along with them, a large quantity of effluents from cities / towns located on either side of these rivers, thus making the Bay nutrient rich. This Bay also plays a major role in determining the climatic conditions of India and other South East Asian countries. Thus its ecology is of paramount interest. Further, the Bay is also known for its oligotrophic nature as well low productivity, thus resulting in high diversity of flora and fauna. The ecological status of the Bay has a direct bearing on the lifescape of the Bay, and therefore, a study was undertaken to understand abiotic and biotic factors with special reference to zooplankton. Based on the observations, the study recommends certain appropriate measures to be taken to conserve the ecology of one of the largest Bay in the world.

  7. Synoptic Bi-monthly and storm response water quality sampling in Southern Kaneohe Bay, Hawaii, from November 2007 - April 2009 (NODC Accession 0062644)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Synoptic sampling including water column profiles and collected surface water samples was conducted on a bi-monthly basis throughout the rainy season (October-May)...

  8. Synoptic Bi-monthly and Storm Response Water Quality Sampling in Southern Kaneohe Bay, HI 2005-2007 (NODC Accession 0060061)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Synoptic sampling including water column profiles and collected surface water samples was conducted on a bi-monthly basis throughout the rainy season(October-May)...

  9. Simultaneous Sea-Level Oscillations in Japanese Bays Induced by the Tsunami of Nankai-Trough Earthquake

    Science.gov (United States)

    Oishi, Y.; Furumura, T.; Imamura, F.; Yamashita, K.; Sugawara, D.

    2016-12-01

    In this study, we investigate the response of bays to the tsunami of Nankai-trough earthquake based on tsunami simulations and demonstrate the possibility that sea-level oscillation of each bay, which is induced by an incident tsunami, interacts with those of other bays. Several major cities in Japan, including the capital, are located in the bays near the Nankai trough and it is assumed that these cities will be largely affected by the tsunamis caused by recurring large earthquakes at the trough. Therefore, it is very important for these populated cities to understand the mechanism and properties of the tsunami-induced oscillations that continue for a long time in bays to draw up evacuation plans. To investigate the response of bays for various tsunamis that may occur in the Nankai trough area, we distributed the tsunami sources that have the form of a 2-D Gaussian function around the Nankai trough. From simulations with these sources, it was found that strong oscillations of bay water occur when the source is located in the bay itself or when strong oscillations occur in other bays. For example, when the Tosa bay oscillates, the Tokyo bay that is 600 km away from the Tosa bay also oscillates. Among the bays around the Nankai trough, the Suruga bay, the deepest bay in Japan with a 2500-km depth, oscillates more strongly than other bays for most cases. To check the influence of the strong oscillations in the Suruga bay on other bays, we conducted tsunami simulations using a modified topography model in which the Suruga bay is artificially landfilled. As a consequence, the strength of oscillations in the adjacent bays are reduced by 20-30%, suggesting the large influence of the distinguished oscillation of the Suruga bay on these bays. We finally conducted tsunami simulations using the eleven Nankai-trough earthquake scenarios of the Central Disaster Prevention Council (CDPC) of Japan as tsunami sources, and the mutual relation regarding the strengths of

  10. Modeling the impacts of winter cover crops on water quality in two adjacent sub-watersheds within the Chesapeake Bay Watershed, Maryland, USA

    Science.gov (United States)

    The Choptank River on Maryland’s Eastern Shore has been designated by the USEPA as “impaired waters” under Section 303(d) of the Federal Clean Water Act of 1972, mainly because of significant nutrient loads that resulted in not meeting the EPA water quality standards. This water quality deteriorati...

  11. 78 FR 53677 - Safety Zone; Battle of Lake Erie Fireworks, Lake Erie, Put-In-Bay, OH

    Science.gov (United States)

    2013-08-30

    ..., Put-In- Bay, OH AGENCY: Coast Guard, DHS. ACTION: Temporary final rule. SUMMARY: The Coast Guard is establishing temporary safety zone in the waters of Lake Erie, Put-In-Bay, Ohio. This zone is intended to... the launching of fireworks in the vicinity of Put-In-Bay, OH on September 1, 2013. The Captain of...

  12. 78 FR 54574 - Safety Zone; Tall Ships Erie 2013 Fireworks Show, Holland Street Pier, Presque Isle Bay, Erie, PA

    Science.gov (United States)

    2013-09-05

    ..., Holland Street Pier, Presque Isle Bay, Erie, PA AGENCY: Coast Guard, DHS. ACTION: Temporary final rule... of Holland Street Pier, Presque Isle Bay in Erie, PA. The Captain of the Port Buffalo has determined... all waters off Holland Street Pier, Presque Isle Bay, Erie, PA within a 420-foot radius of position...

  13. Hydrographical features of the southern and central Bay of Bengal during the transition period between winter and summer

    Digital Repository Service at National Institute of Oceanography (India)

    Rao, L.V.G.; Jayaraman, R.

    mass, which resembles the "Southern Bay of Bengal Water" with the salinity range 33.0-34.0 ppt and sigma t range 21.0-22.0 is identified in the upper 100 metres of the Southern Bay and the western and middle parts of the Central Bay. Throughout...

  14. 大连湾沉积物-水界面BAP交换通量的影响因素%The influencing factors of BAP exchange flux at the sediment-water interface in Dalian Bay

    Institute of Scientific and Technical Information of China (English)

    宗虎民; 张志锋; 王燕; 张哲

    2012-01-01

    The influencing factors of BAP (bio-available phosphorus) exchange flux at the sediment-water interface in Dalian Bay were studied by laboratory incubation experiment, and the BAP fluxes between sediment and water in the dredged area and in the area near the sediment dredging location were analyzed with the methods of laboratory incubation experiment and nutrient concentration gradients in the pore water. The results showed that the fluxes of BAP from sediment to water increased with the increase of pH and temperature in overlying water, and it also increased by the condition of applying sterilized sediment and aerating in overlying water during the incubation experiment. The fluxes from sediment to water decreased when the concentrations of phosphorus increased in the overlying water, and the flux direction reversed with the continuous increase of the concentrations. Both results of the two methods showed that the annual average exchange flux of BAP between sediment and water in the area near the sediment dredging location was higher than that in dredged area affected by dredging works. The exchange fluxes of BAP between sediment and water in Dalian Bay were different in four seasons, which was highest in summer and lowest in winter. However, it was at a high level in the area near the sediment dredging location in winter due to the impact of dredging.%利用实验室培养法研究了不同因素对大连湾沉积物-水界面间生物可利用磷(BAP)交换通量的影响,并利用实验室培养法和间隙水浓度梯度法估算了大连湾已疏浚区和疏浚点邻近海域沉积物-水界面BAP的交换通量.结果表明,随着上覆水pH和温度的增加,BAP由沉积物向水体释放量逐渐增加;灭菌和贫氧条件下,也会导致沉积物BAP的释放量增加;上覆水中磷酸盐浓度的升高会导致BAP由沉积物向水体释放通量降低,且随着上覆水磷酸盐浓度的不断升高,BAP逐渐转化为由水体向沉积物中扩散.

  15. Lost lake - restoration of a Carolina bay

    Energy Technology Data Exchange (ETDEWEB)

    Hanlin, H.G.; McLendon, J.P. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology; Wike, L.D. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology]|[Westinghouse Savannah River Co., Aiken, SC (United States). Savannah River Technology Center; Dietsch, B.M. [Univ. of South Carolina, Aiken, SC (United States). Dept. of Biology and Geology]|[Univ. of Georgia, Aiken, SC (United States)

    1994-09-01

    Carolina bays are shallow wetland depressions found only on the Atlantic Coastal Plain. Although these isolated interstream wetlands support many types of communities, they share the common features of having a sandy margin, a fluctuating water level, an elliptical shape, and a northwest to southeast orientation. Lost Lake, an 11.3 hectare Carolina bay, was ditched and drained for agricultural production before establishment of the Savannah River Site in 1950. Later it received overflow from a seepage basin containing a variety of chemicals, primarily solvents and some heavy metals. In 1990 a plan was developed for the restoration of Lost Lake, and restoration activities were complete by mid-1991. Lost Lake is the first known project designed for the restoration and recovery of a Carolina bay. The bay was divided into eight soil treatment zones, allowing four treatments in duplicate. Each of the eight zones was planted with eight species of native wetland plants. Recolonization of the bay by amphibians and reptiles is being evaluated by using drift fences with pitfall traps and coverboard arrays in each of the treatment zones. Additional drift fences in five upland habitats were also established. Hoop turtle traps, funnel minnow traps, and dip nets were utilized for aquatic sampling. The presence of 43 species common to the region has been documented at Lost Lake. More than one-third of these species show evidence of breeding populations being established. Three species found prior to the restoration activity and a number of species common to undisturbed Carolina bays were not encountered. Colonization by additional species is anticipated as the wetland undergoes further succession.

  16. 78 FR 55216 - Safety Zone: Suisun Bay Electromagnetic Scan and Ordnance Recovery, Suisun Bay, Concord, CA

    Science.gov (United States)

    2013-09-10

    ... Acronyms DHS Department of Homeland Security DoD Department of Defense FR Federal Register MMRP Military..., 2013 in the navigable waters of the Suisun Bay, CA as depicted in National Oceanic and Atmospheric... and Interference with Constitutionally Protected Property Rights. 9. Civil Justice Reform This...

  17. The Fermi's Bayes Theorem

    CERN Document Server

    D'Agostini, G

    2005-01-01

    It is curious to learn that Enrico Fermi knew how to base probabilistic inference on Bayes theorem, and that some influential notes on statistics for physicists stem from what the author calls elsewhere, but never in these notes, {\\it the Bayes Theorem of Fermi}. The fact is curious because the large majority of living physicists, educated in the second half of last century -- a kind of middle age in the statistical reasoning -- never heard of Bayes theorem during their studies, though they have been constantly using an intuitive reasoning quite Bayesian in spirit. This paper is based on recollections and notes by Jay Orear and on Gauss' ``Theoria motus corporum coelestium'', being the {\\it Princeps mathematicorum} remembered by Orear as source of Fermi's Bayesian reasoning.

  18. 33 CFR 334.120 - Delaware Bay off Milford Neck; naval aircraft bombing target area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Delaware Bay off Milford Neck; naval aircraft bombing target area. 334.120 Section 334.120 Navigation and Navigable Waters CORPS OF....120 Delaware Bay off Milford Neck; naval aircraft bombing target area. (a) The danger zone. A circular...

  19. 33 CFR 110.82a - Little Traverse Bay, Lake Michigan, Harbor Springs, Mich.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Little Traverse Bay, Lake Michigan, Harbor Springs, Mich. 110.82a Section 110.82a Navigation and Navigable Waters COAST GUARD... Traverse Bay, Lake Michigan, Harbor Springs, Mich. (a) Area 1. Beginning at latitude 45°25′42.2″...

  20. 33 CFR 207.470 - Sturgeon Bay and Lake Michigan Ship Canal, Wis.; use and navigation.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Sturgeon Bay and Lake Michigan Ship Canal, Wis.; use and navigation. 207.470 Section 207.470 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE NAVIGATION REGULATIONS § 207.470 Sturgeon Bay and Lake Michigan Ship Canal, Wis.; use...

  1. 33 CFR 334.930 - Anaheim Bay Harbor, Calif.; Naval Weapons Station, Seal Beach.

    Science.gov (United States)

    2010-07-01

    ... Weapons Station, Seal Beach. 334.930 Section 334.930 Navigation and Navigable Waters CORPS OF ENGINEERS... Bay Harbor, Calif.; Naval Weapons Station, Seal Beach. (a) The restricted area. The water of Anaheim Bay Harbor between the east and west jetties at the United States Naval Weapons Station, Seal Beach...

  2. 33 CFR 110.79b - Millers Bay, Lake Winnebago, Oshkosh, WI

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false Millers Bay, Lake Winnebago, Oshkosh, WI 110.79b Section 110.79b Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND..., Oshkosh, WI The area adjacent to Menominee Park in Millers Bay within the following boundaries:...

  3. 33 CFR 165.1110 - Security Zone: Coronado Bay Bridge, San Diego, CA.

    Science.gov (United States)

    2010-07-01

    ... Bridge, San Diego, CA. 165.1110 Section 165.1110 Navigation and Navigable Waters COAST GUARD, DEPARTMENT... § 165.1110 Security Zone: Coronado Bay Bridge, San Diego, CA. (a) Location. All navigable waters of San Diego Bay, from the surface to the sea floor, within 25 yards of all piers, abutments, fenders and...

  4. Calculation of Environmental Capacity of Petroleum Hydrocarbon in Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    李克强; 王修林; 邓宁宁; 石晓勇; 祝陈坚; 韩秀荣; 胡海燕

    2004-01-01

    The method has been established to calculate the environmental capacity (ECo),surplus environment capacity (SECo) of water with respect to marine petroleum hydrocarbons associated with oil (PHAOs) and the self-purification capacity (SPCo) of main self-purification process to PHAOs in the Jiaozhou Bay, China, according to the dynamic model for distribution of marine PHAOs among multiphase environments. The variation of concentration of PHAOs in the Jiaozhou Bay is well simulated by the dynamic model. Based on the model,the EC., SEC. of water with respect to PHAOs in the Jiaozhou Bay were calculated during the last 10 years under the first-class and second-class quality standard requirement, according to SPCoof main self-purification process to PHAOs. The results show that about 200 tons of PHAOs could be discharged into the Jiaozhou Bay for maintaining the first class seawater quality standard, and about 600 tons of PHAOs for the second class seawater quality standard later.

  5. Concept and evaluation of bay health:the role of numerical model in the Yueqing Bay, China

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dacheng; SUN Zhilin; HUANG Yu; HUANG Saihua; LI Li

    2016-01-01

    To better evaluate the three-dimensional bay health and predict the dynamic bay health conditions, a concept of numerical bay health was introduced and a method of numerical bay health evaluation (NBHE) was developed. To support the NBHE method, a numerical bay health index (NBHI) system was constructed, which assess the natural and socio-economic effects on the entire bay. Five index groups are combined to formulate the NBHI, including geometry, hydrodynamics and sediment dynamics, bio-ecology, water quality and socio-economy. Each group has different number of indices selected and weighted using AHP method according to their importance. Data were mainly synthesized from a variety of numerical models together with monitoring programs, which provide superior to other approaches in discriminating data integrity and predicting data in future. The NBHE method using NBHI system was applied in the Yueqing Bay during spring tide in April 2007. According to the NBHE results, Sta. A, at the surface level of the estuarine mouth, has a healthy geometry condition, sub-healthy hydrodynamic and sediment dynamic condition, and unhealthy water quality and bio-ecology conditions. The integrated healthy score at Sta. A indicates its sub-healthy condition.

  6. Seasonal accumulations of some heavy metal in water, sediment and tissues of black-chinned tilapia Sarotherodon melanotheron from Biétri Bay in Ebrié Lagoon, Ivory Coast.

    Science.gov (United States)

    Coulibaly, Safiatou; Atse, Boua Célestin; Koffi, Kouamé Mathias; Sylla, Soumaïla; Konan, Kouadio Justin; Kouassi, N'Guessan Joël

    2012-04-01

    The seasonal accumulation of cadmium, copper, lead, mercury and zinc was determined in sediments, water, and black-chinned tilapia (Sarotherodon melanotheron; muscle, brain, kidney and liver tissues) collected monthly from Biétri Bay. The mean water concentration of metals (in mg L(-1)) ranged from 0.01 to 0.30 (mercury), 0.02-0.26 (cadmium), 2.40-4.80 (lead), 9.05-9.68 (copper), and 12.05-19.87 (zinc). The seasonal variations showed a significant difference in the levels of mercury, cadmium and lead among season. The highest mercury (0.30 ± 0.02 μg L(-1)), cadmium (0.26 ± 0.02 mg L(-1)) and lead (4.80 ± 1.03 mg L(-1)) levels were observed during dry season, while the lowest levels (0.21 ± 0.01, 0.02 ± 0.01 and 2.40 ± 0.02 mg L(-1), respectively mercury, cadmium and lead) were measured during rainy season. The average cadmium (0.58 ± 0.36 mg L(-1)), copper (42.15 ± 19.40 mg L(-1)), lead (58.47 ± 38.10 mg kg(-1)), mercury (0.79 ± 0.47 μg kg(-1)) and zinc (187.58 ± 76.99 mg kg(-1)) concentrations determined in Biétri Bay sediments showed a similar trend as in water. The seasonal variations of mercury, cadmium and lead in tissues revealed that these metals were higher concentrated during dry and swelling seasons. The levels of zinc and copper followed by lead were higher in the tissues. The order of tissues metals concentrations was: kidney > liver > brain > muscle.

  7. Earthquake and bay: Response of Monterey Bay to the Loma Prieta Earthquake

    Science.gov (United States)

    Schwing, Franklin B.; Norton, Jerrold G.; Pilskaln, Cynthia H.

    The magnitude-7.1 Loma Prieta earthquake, which ruptured a segment of the San Andreas fault on October 17, 1989, and caused extensive damage over a large area of central California, also produced substantial motions in nearby Monterey Bay (Figure 1). Earthquake effects included a tsunami, or seismic sea wave, and subsequent surface water oscillations that were detected for about 24 hours following the main shock and widespread, substantial slumping of sediments on the Monterey Bay continental shelf and along the walls of Monterey Submarine Canyon.

  8. Sessile animals` distribution and their water quality purification function in Tokyo inner bay; Tokyoto naiwan ni okeru fuchaku dobutsu no bunpu to suishitsu joka kino

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, K.; Tsuchiya, T. [Tokyo Metropolitan Research Inst. for Environmental Protection, Tokyo (Japan); Inamori, Y. [National Inst. for Environmental Studies, Tsukuba (Japan); Okutomi, S. [Saitama University, Saitama (Japan). Faculty of Engineering; Nishimura, O.; Sudo, R. [Tohoku University, Sendai (Japan)

    1998-01-10

    With sea banks in the Tokyo Inner Bay as the object, discussions were given on identification of actual living conditions for sessile animals and purification function of their dominant species. In the investigation, submerged visual observations and identification on existing quantities were performed in July, September and November, 1995 and February 1996. The following matters were made clear as a result of the investigation: the number of species ranges from 43 to 46 and is stabilized throughout a year; a phenomenon is repeated that the number of individuals decreases in summer and winter, and increases in spring and fall as breeding seasons as a result of the addition of larva; the existing quantity is accounted for 90% or more by four dominant species of M. e. galloprovincialis, L. f. kikuchii, C. gigas and Balanus spp in that order; sessile animals weighing 9,110 tons are living annually in average in the sea banks extending over a distance of 192 km; amount of COD purification based on the annual average deposition quantity is calculated 19 tons as a daily average, which corresponds to 23% of the total COD quantity flowing in from the Tokyo urban area; and on the other hand, COD, N and P produced by sessile animals become new loads to environment over the life of these sessile animals. 26 refs., 6 figs., 2 tabs.

  9. Distribution of particulate carbohydrate species in the Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Khodse, V.B.; Bhosle, N.B.; Gopalakrishna, V.V.

    and terrestrial organ- isms. The storage carbohydrates are utilized pre- ferentially. This results in the accumulation of relatively less degradable structural carbohydrates in the degraded organic matter. In addition to neutral carbohydrates, many marine micro... transport of nutrients into surface waters. Moreover, the weak winds are unable to break the thermocline. Upwelling has been observed along the western boundary of the Bay (Shetye et al 1991). Cyclones are fre- quent in the Bay, and can pump nutrients...

  10. Nitrogen and phosphorus intake by phytoplankton in the Xiamen Bay

    Institute of Scientific and Technical Information of China (English)

    林彩; 林辉; 贺青; 许焜灿; 吴省三; 张元标; 陈金民; 陈宝红; 林力斌; 卢美鸾; 陈维芬; 汤荣坤; 暨卫东

    2010-01-01

    This paper describes a time series experiment examining the nitrogen and phosphorus intake of natural phytoplankton communities by a microcosms approach.Seawater samples containing natural phytoplankton communities were collected from waters around Baozhu Islet in inner Xiamen Bay and around Qingyu Islet in the outer bay.The goal was to elucidate the relationship between phytoplankton population enhancement,the biological removal of nitrogen and phosphorus from the seawater,and the phytoplankton nitrogen an...

  11. Bay of Bengal Surface and Thermocline and the Arabian Sea

    Science.gov (United States)

    2014-09-30

    BoB) is affected by many contrasting water types. The strong monsoonal forcing induces a complex array of energetic meso-scale and sub-meso-scales...COMPLETED Argo data has been assembled to build a climatology (2003-2014) of the thermohaline stratification within the Bay of Bengal. This product ... IOD , hold promise as a simple, yet effective means of predicting an IOD event’. 10 IMPACT/APPLICATIONS The Bay of Bengal complex, energetic

  12. A summer monsoon pump to keep the Bay of Bengal salty

    Digital Repository Service at National Institute of Oceanography (India)

    Vinayachandran, P.N.; Shankar, D; Vernekar, S.; Sandeep, K.K.; Amol, P.; Neema, C.P.; Chatterjee, A.

    Institute of Oceanography, Dona Paula, Goa 403004, India. D R A F T January 21, 2013, 11:04am D R A F T Geophys. Res. Lett., vol.40; 2013; 1777-1782 X - 2 VINAYACHANDRAN ET AL.: BAY OF BENGAL SALT PUMP The Bay of Bengal receives a large influx of freshwater... this saltier water into the rest of the basin, allowing the bay to stay salty despite a large net fresh- water input. D R A F T January 21, 2013, 11:04am D R A F T VINAYACHANDRAN ET AL.: BAY OF BENGAL SALT PUMP X - 3 1. Introduction The Northern Indian Ocean...

  13. Tidal pumping - missing factor in glacial bays evolution?

    Science.gov (United States)

    Szczucinski, Witold; Moskalik, Mateusz; Dominiczak, Aleksander

    2017-04-01

    Most of the glaciers worldwide are subjected to rapid retreat. It is particularly well visible in Svalbard, where tidewater glaciers after the termination of the Little Ice Age often resulted in formation of new glacial bays. These bays are specific environments, characterised by high sediment accumulation rates, seasonal formation of sea-ice cover and common presence of icebergs. They are usually separated from the rest of the fjord by shallow (e.g. submerged moraine) or narrow passages. Although hostile, these bays also host unique ecosystems, with particular importance as feeding grounds for seals and sea birds. Among factors considered in development of such environments the role of tides is usually neglected or assumed as constant. Here we would like to stress the increasing role of tides in development of glacial bays ecosystems, as well as for import and burial of organic carbon in the bays. We present a model of tide development and results on present day conditions from Brepolen bay in Hornsund (southern Spitsbergen). On the basis of ADCP and CTD surveys we present the modern conditions and water exchange rates between the glacial bay and the fjord. Analysis of archival satellite images, aerial photographs and historical maps was used to map the change in glacial bay area. Finally simple modeling allow to identify a linear increase in tidal pumping magnitude (water exchange due to tides) with increasing glacial bay area due to glaciers retreat. We discuss it in context of potential consequences for bay oceanography, ecology and sedimentation. With fast glacier retreat and rapid grow of glacial bays one may expect the following effects of increasing tidal pumping: enhanced water exchange with the central part of the fjord, increasing salinity, facilitating colonisation by new species (e.g. import of juvenile forms of benthic species), increased input of marine organic carbon into setting suitable for its burial (high sediment accumulation rate in glacial

  14. New records of marine water mites (Acari: Hydrachnidia: Pontarachnidae) from the Pujada Bay (West Pacific Ocean) and the Andaman Sea (Indian Ocean)

    Digital Repository Service at National Institute of Oceanography (India)

    Pesic, V.; Chatterjee, T.; Troch, M. de; Ingole, B.S.

    and macroalgae were washed through 38 mu m sieves using the sea water to extract the animals and preserved in 70% alcohol; water mites were separated under a binocular microscope. All specimens are deposited in the Museum of Natural History of Podgorica...

  15. Status, trends, and changes in freshwater inflows to bay systems in the Corpus Christi Bay National Estuary Program study area

    Science.gov (United States)

    Asquith, W.H.; Mosier, J. G.; Bush, P.W.

    1997-01-01

    This report presents the results of a study to quantify current (1983–93) mean freshwater inflows to the six bay systems (open water and wetlands) in the Corpus Christi Bay National Estuary Program study area, to test for historical temporal trends in inflows, and to quantify historical and projected changes in inflows. The report also addresses the adequacy of existing data to estimate freshwater inflows.

  16. Richards Bay effluent pipeline

    CSIR Research Space (South Africa)

    Lord, DA

    1986-07-01

    Full Text Available This report discusses the adequate provision for waste disposal is an essential part of the infrastructure needed in the development of Richards Bay as a deepwater harbour and industrial/metropolitan area. Having considered various options for waste...

  17. Eutrophication influence on phytoplankton community composition in three bays on the eastern Adriatic coast

    Directory of Open Access Journals (Sweden)

    Mia Bužančić

    2016-10-01

    Full Text Available This study shows the influence of eutrophication pressure on the phytoplankton community structure, abundance and biodiversity in the investigated bays with different hydromorphological features. Šibenik Bay is a highly stratified estuary of the karstic river Krka; Kaštela Bay is a semi-enclosed coastal bay, which is influenced by the relatively small river Jadro; and Mali Ston Bay is located at the Neretva River estuary, the largest river on the eastern part of the Adriatic Sea. All of the areas are affected by urban pressure, which is reflected in the trophic status of the waters. The greatest anthropogenic influence was found in Kaštela Bay while the lowest influence was found in Mali Ston Bay. In this study, the highest biomass concentration and maximum abundance of phytoplankton were recorded at the stations under the strongest anthropogenic influence. Those stations show a dominance of abundance compared to the biomass and a dominance of opportunistic species, which is reflected in the lower biodiversity of phytoplankton community. Diatoms were the most represented group of the phytoplankton community in all three bays, followed by the dinoflagellates. Diatoms that were highlighted as significant for the difference between the bays were Skeletonema marinoi in Šibenik Bay, Leptocylindrus minimus in Kaštela Bay and the genus Chaetoceros spp. in Mali Ston Bay. Dinoflagellates were more abundant at the stations under the strongest anthropogenic influence, and most significant were Prorocentrum triestinum in Kaštela Bay and Gymnodinium spp. in Šibenik Bay and Mali Ston Bay.

  18. Role of environment and hydrography in determining the picoplankton community structure of Sagami Bay, Japan

    Digital Repository Service at National Institute of Oceanography (India)

    Mitbavkar, S.; Saino, T.; Horimoto, N.; Kanda, J.; Ishimaru, T.

    Seasonal variations in the picoplankton community were investigated from June 2002 to March 2004 within the photic zone of Sagami Bay, Japan. The study area was mostly dominated by coastal waters during the warm period (mixed layer water temperature...

  19. Near-Field Receiving Water Monitoring of Trace Metals and a Benthic Community Near the Palo Alto Regional Water Quality Control Plant in South San Francisco Bay, California: 2004

    Science.gov (United States)

    2005-01-01

    private contractor familiar with the taxonomy of San Francisco Bay invertebrates (Susan McCormick, Colfax, CA) (Appendix H). S. McCormick also...0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Unid. Isopoda 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.6667 1.15 0 0 0 0 Unid. Nudibranchia 0 0 0 0 0 0 0 0 0 0 0

  20. Pore water composition of Permeable reef flat sediments on Checker Reef in Kaneohe Bay, Oahu, Hawaii from 07 October 1996 to 03 July 1997 (NODC Accession 0000271)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Geochemical behaviour of the top 70 cm of permeable reef flat sediments on Checker Reef, Oahu, Hawaii was examined using spatial and temporal changes in pore water...

  1. Pawcatuck River and Narragansett Bay Drainage Basins Water and Related Land Resources Study. Big River Reservoir Project. Volume II. Appendix A-G.

    Science.gov (United States)

    1981-07-01

    usage have been proposed and some are being marketed on a small scale. Advantages of this system, beyond potable water consumption decrease, are the...and the threat to human life, aside from the adverse effects on socia ] well-being and regional development, associated with water shortages. The...such as targeted mailings, media involve- ment, information bulletins, and public contact such as workshops, briefing sessions and various formal and

  2. Topobathymetric model of Mobile Bay, Alabama

    Science.gov (United States)

    Danielson, Jeffrey J.; Brock, John C.; Howard, Daniel M.; Gesch, Dean B.; Bonisteel-Cormier, Jamie M.; Travers, Laurinda J.

    2013-01-01

    Topobathymetric Digital Elevation Models (DEMs) are a merged rendering of both topography (land elevation) and bathymetry (water depth) that provides a seamless elevation product useful for inundation mapping, as well as for other earth science applications, such as the development of sediment-transport, sea-level rise, and storm-surge models. This 1/9-arc-second (approximately 3 meters) resolution model of Mobile Bay, Alabama was developed using multiple topographic and bathymetric datasets, collected on different dates. The topographic data were obtained primarily from the U.S. Geological Survey (USGS) National Elevation Dataset (NED) (http://ned.usgs.gov/) at 1/9-arc-second resolution; USGS Experimental Advanced Airborne Research Lidar (EAARL) data (2 meters) (http://pubs.usgs.gov/ds/400/); and topographic lidar data (2 meters) and Compact Hydrographic Airborne Rapid Total Survey (CHARTS) lidar data (2 meters) from the U.S. Army Corps of Engineers (USACE) (http://www.csc.noaa.gov/digitalcoast/data/coastallidar/). Bathymetry was derived from digital soundings obtained from the National Oceanic and Atmospheric Administration’s (NOAA) National Geophysical Data Center (NGDC) (http://www.ngdc.noaa.gov/mgg/geodas/geodas.html) and from water-penetrating lidar sources, such as EAARL and CHARTS. Mobile Bay is ecologically important as it is the fourth largest estuary in the United States. The Mobile and Tensaw Rivers drain into the bay at the northern end with the bay emptying into the Gulf of Mexico at the southern end. Dauphin Island (a barrier island) and the Fort Morgan Peninsula form the mouth of Mobile Bay. Mobile Bay is 31 miles (50 kilometers) long by a maximum width of 24 miles (39 kilometers) with a total area of 413 square miles (1,070 square kilometers). The vertical datum of the Mobile Bay topobathymetric model is the North American Vertical Datum of 1988 (NAVD 88). All the topographic datasets were originally referenced to NAVD 88 and no transformations

  3. Measuring Macrobenthos Biodiversity at Oyster Aquaculture Sites in the Delaware Inland Bays

    Science.gov (United States)

    Fuoco, M. J.; Ozbay, G.

    2016-12-01

    The Delaware Inland Bays consists of three shallow coastal bays located in the southern portion of Delaware. Anthropogenic activities have led to the degradation of water quality, because the bays are surrounded by highly developed areas and have low flushing rates. This results in loss of biodiversity and abundance of organisms. Ongoing degradation of the bays has led to a dramatic decline in local oyster populations since the late 1800s. Oysters are keystone species, which provide habitats for organisms and help to improve water quality. This study aims to find if the introduction of oyster aquaculture improves local biodiversity and abundance of macrobenthos. The study was conducted in Rehoboth Bay, Indian River Bay and Little Assawoman Bay. Aquaculture gear was placed at one location in each of the bays and 24 sediment core samples were taken once a month. From these core samples all worms were fixed and stained in a 10% Formalin Rose Bengal solution and preserved in 70% Ethanol for later identification. Stable carbon and nitrogen isotope analysis of oyster tissue will also be performed to assess the health of the bay. The goals of this research are to better understand the role of oyster aquaculture in restoring the viability and health of the Delaware Inland Bays.

  4. Defining a data management strategy for USGS Chesapeake Bay studies

    Science.gov (United States)

    Ladino, Cassandra

    2013-01-01

    The mission of U.S. Geological Survey’s (USGS) Chesapeake Bay studies is to provide integrated science for improved understanding and management of the Chesapeake Bay ecosystem. Collective USGS efforts in the Chesapeake Bay watershed began in the 1980s, and by the mid-1990s the USGS adopted the watershed as one of its national place-based study areas. Great focus and effort by the USGS have been directed toward Chesapeake Bay studies for almost three decades. The USGS plays a key role in using “ecosystem-based adaptive management, which will provide science to improve the efficiency and accountability of Chesapeake Bay Program activities” (Phillips, 2011). Each year USGS Chesapeake Bay studies produce published research, monitoring data, and models addressing aspects of bay restoration such as, but not limited to, fish health, water quality, land-cover change, and habitat loss. The USGS is responsible for collaborating and sharing this information with other Federal agencies and partners as described under the President’s Executive Order 13508—Strategy for Protecting and Restoring the Chesapeake Bay Watershed signed by President Obama in 2009. Historically, the USGS Chesapeake Bay studies have relied on national USGS databases to store only major nationally available sources of data such as streamflow and water-quality data collected through local monitoring programs and projects, leaving a multitude of other important project data out of the data management process. This practice has led to inefficient methods of finding Chesapeake Bay studies data and underutilization of data resources. Data management by definition is “the business functions that develop and execute plans, policies, practices and projects that acquire, control, protect, deliver and enhance the value of data and information.” (Mosley, 2008a). In other words, data management is a way to preserve, integrate, and share data to address the needs of the Chesapeake Bay studies to better

  5. Controls on residence time and exchange in a system of shallow coastal bays

    Science.gov (United States)

    Safak, I.; Wiberg, P. L.; Richardson, D. L.; Kurum, M. O.

    2015-04-01

    Patterns of transport and residence time influence the morphology, ecology and biogeochemistry of shallow coastal bay systems in important ways. To better understand the factors controlling residence time and exchange in coastal bays, a three-dimensional finite-volume coastal ocean model was set up and validated with field observations of circulation in a system of 14 shallow coastal bays on the Atlantic coast of the USA (Virginia Coast Reserve). Residence times of neutrally buoyant particles as well as exchange among the bays in the system and between the bays and the ocean were examined with Lagrangian particle tracking. There was orders of magnitude variation in the calculated residence time within most of the bays, ranging from hours in the tidally refreshed (repletion) water near the inlets to days-weeks in the remaining (residual) water away from the inlets. Residence time in the repletion waters was most sensitive to the tidal phase (low vs. high) when particles were released whereas residence time in the residual waters was more sensitive to wind forcing. Wind forcing was found to act as a diffuser that shortens particle residence within the bays; its effect was higher away from the inlets and in relatively confined bays. Median residence time in the bays significantly decreased with an increase in the ratio between open water area and total area (open water plus marsh). Exchange among the bays and capture areas of inlets (i.e., exchange between the bays and the ocean) varied considerably but were insensitive to tidal phase of release, wind, and forcing conditions in different years, in contrast to the sensitivity of residence time to these factors. We defined a new quantity, termed shortest-path residence time, calculated as distance from the closest inlet divided by root-mean-square velocity at each point in model domain. A relationship between shortest-path residence time and particle-tracking residence time provides a means of estimating residence time

  6. Nutrient load estimates for Manila Bay, Philippines using population data

    NARCIS (Netherlands)

    Sotto, Lara Patricia A; Beusen, Arthur H W; Villanoy, Cesar L.; Bouwman, Lex F.; Jacinto, Gil S.

    2015-01-01

    A major source of nutrient load to periodically hypoxic Manila Bay is the urban nutrient waste water flow from humans and industries to surface water. In Manila alone, the population density is as high as 19,137 people/km2. A model based on a global point source model by Morée et al. (2013) was used

  7. Nutrient load estimates for Manila Bay, Philippines using population data

    NARCIS (Netherlands)

    Sotto, Lara Patricia A; Beusen, Arthur H W|info:eu-repo/dai/nl/109357302; Villanoy, Cesar L.; Bouwman, Lex F.|info:eu-repo/dai/nl/090428048; Jacinto, Gil S.

    2015-01-01

    A major source of nutrient load to periodically hypoxic Manila Bay is the urban nutrient waste water flow from humans and industries to surface water. In Manila alone, the population density is as high as 19,137 people/km2. A model based on a global point source model by Morée et al. (2013) was used

  8. Coastal Acidification as Nutrients Over Enrichment Impact: A Case Study in Ambon Bay, Indonesia

    Directory of Open Access Journals (Sweden)

    Idha Yulia Ikhsani

    2017-05-01

    Full Text Available Ambon Bay is a silled bay on Ambon Island consisting of two regions, Inner Ambon Bay (IAB and Outer Ambon Bay (OAB that are separated by shallow sill. Ambon bay and its surrounding have economically important ecosystem since the utilization for many activities. The bay is affected by anthropogenic impacts associated with urbanization, climate change, and nutrients over enrichment. The “deep water-rich nutrients” from Banda Sea that enter the bay during Southeast monsoon also contribute to this enrichment as well as the nutrients transport from the land. The high concentration of nutrients increases carbon dioxide level and promotes acidifications. There are literatures about nutrients over enrichment in Ambon Bay, however, little is known about coastal acidification as nutrients over enrichment impact. In order to study the effect of nutrients distribution on the acidity of Ambon Bay, the researchers measured pH and concentrations of nutrients {nitrate + nitrite (N+N and Soluble Reactive Phosphate (SRP} from water samples collected in 7 stations on both IAB and OAB during Southeast monsoon. The results showed that in surface water, nutrients concentrations is increased from May to June due to the “deep water flushing” occurrence on May and increased precipitations from May to June. From July to August, the nutrients concentrations on surface layer decreased, due to the decreased precipitations. In column and bottom water, the nutrients concentrations were increased from May to August. While the acidity have reverse pattern from the nutrients, when nutrient concentrations increased the acidity was decreased. From correlation test, pH was not significantly correlated with the concentrations of nutrients on surface water, but showed significantly correlated on column and bottom water. The results indicated that the distribution of nutrients on column and bottom water might be an important environmental factor affecting the acidification of

  9. Field guide to fishes of the chesapeake bay

    CERN Document Server

    Murdy, Edward O.

    2013-01-01

    The only comprehensive field guide to the Chesapeake’s fishes, this book is an indispensable resource for both anglers and students of the Bay. Vivid illustrations by Val Kells complement the expertise of researchers Edward O. Murdy and John A. Musick. They describe fishes that inhabit waters ranging from low-salinity estuaries to the point where the Bay meets the Atlantic Ocean. Key features of this field guide include• full-color illustrations of more than 200 species• text that is presented adjacent to illustrations for easy reference• detailed descriptions of physical characteristics, range, occurrence in the Bay, reproduction, diet, and statistics from fisheries research• spot illustrations that highlight critical features of certain fish• illustrations of juveniles when they look different from adults• appendices that include identification keys Formatted as a compact field guide for students, scientists, researchers, and fishermen, Field Guide to Fishes of the Chesapeake Bay should be a ...

  10. Assessment of surface water chemistry and algale biodiversity in the Bay of Mostaganem and the Cheliff estuary: North-western Algeria

    OpenAIRE

    Fatima kies

    2015-01-01

    Anthropogenic activities have led to water quality deterioration in many parts of the word, especially in Northwest Algeria. The current work investigated the spatiotemporal variations of water quality in the Cheliff River, samples for physico-chemical were performed at different periods from 2004 to 2007, the results chowed that nitrate (NO3-) intake is very high especially in the month of February 2006 (26 mg/l) and February 2007 (37 mg/l), nitrite (NO2-) values also exceed the standard fo...

  11. Research on Hydraulic Block Scenarios in the Land Conservation Zone of the Headwaters Area of Jinshu Bay

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    [Objective] The aim was to study the hydraulic block scenarios in the water source land conservation zone in Jinshu Bay so as to ensure the water quality in the water sources in Jinshu Bay.[Method] By dint of one dimension water amount and water quality mode in the river net in Taihu,the water flow movement characteristics and pollutants transportation rules in the water sources areas in Jinshu Bay under five kinds of hydraulic block scenarios were compared and discussed.[Result] After demolishing the tempo...

  12. Big River Reservoir Project. Pawcatuck River and Narragansett Bay Drainage Basins. Water and Related Land Resources Study. Volume I. Main Report.

    Science.gov (United States)

    1981-07-01

    AGRICULTURAL EXPERIMENT STATION, UNIVERSITY OF RHODE ISLAND DEPT OF FORESTRY - KUPA a WHITMAN Z=- RurE 1-9!5 /e ALCARR POND SWIMMING. PICNIC, BOATING...Rhode Island Bonnie Cimino/ Barry Schiller Environmental Consultant Dr. John Kupa Kent County Water Authority Norman St. Serveire Natural Resources

  13. Environmental and Sanitary Conditions of Guanabara Bay, Rio de Janeiro

    Science.gov (United States)

    Fistarol, Giovana O.; Coutinho, Felipe H.; Moreira, Ana Paula B.; Venas, Tainá; Cánovas, Alba; de Paula, Sérgio E. M.; Coutinho, Ricardo; de Moura, Rodrigo L.; Valentin, Jean Louis; Tenenbaum, Denise R.; Paranhos, Rodolfo; do Valle, Rogério de A. B.; Vicente, Ana Carolina P.; Amado Filho, Gilberto M.; Pereira, Renato Crespo; Kruger, Ricardo; Rezende, Carlos E.; Thompson, Cristiane C.; Salomon, Paulo S.; Thompson, Fabiano L.

    2015-01-01

    Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of the current environmental and sanitary conditions of Guanabara Bay, a consequence of all these decades of impacts. We will focus on microbial communities, how they may affect higher trophic levels of the aquatic community and also human health. The anthropogenic impacts in the bay are flagged by heavy eutrophication and by the emergence of pathogenic microorganisms that are either carried by domestic and/or hospital waste (e.g., virus, KPC-producing bacteria, and fecal coliforms), or that proliferate in such conditions (e.g., vibrios). Antibiotic resistance genes are commonly found in metagenomes of Guanabara Bay planktonic microorganisms. Furthermore, eutrophication results in recurrent algal blooms, with signs of a shift toward flagellated, mixotrophic groups, including several potentially harmful species. A recent large-scale fish kill episode, and a long trend decrease in fish stocks also reflects the bay’s degraded water quality. Although pollution of Guanabara Bay is not a recent problem, the hosting of the 2016 Olympic Games propelled the government to launch a series of plans to restore the bay’s water quality. If all plans are fully implemented, the restoration of Guanabara Bay and its shores may be one of the best legacies of the Olympic Games in Rio de Janeiro. PMID:26635734

  14. Environmental and sanitary conditions of Guanabara Bay, Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Giovana De Oliveira Fistarol

    2015-11-01

    Full Text Available Guanabara Bay is the second largest bay in the coast of Brazil, with an area of 384 km2. In its surroundings live circa 16 million inhabitants, out of which 6 million live in Rio de Janeiro city, one of the largest cities of the country, and the host of the 2016 Olympic Games. Anthropogenic interference in Guanabara Bay area started early in the XVI century, but environmental impacts escalated from 1930, when this region underwent an industrialization process. Herein we present an overview of the current environmental and sanitary conditions of Guanabara Bay, a consequence of all these decades of impacts. We will focus on microbial communities, how they may affect higher trophic levels of the aquatic community and also human health. The anthropogenic impacts in the bay are flagged by heavy eutrophication and by the emergence of pathogenic microorganisms that are either carried by domestic and/or hospital waste (e.g. virus, KPC-producing bacteria, and fecal coliforms, or that proliferate in such conditions (e.g. vibrios. Antibiotic resistance genes are commonly found in metagenomes of Guanabara Bay planktonic microorganisms. Furthermore, eutrophication results in recurrent algal blooms, with signs of a shift towards flagellated, mixotrophic groups, including several potentially harmful species. A recent large-scale fish kill episode, and a long trend decrease in fish stocks also reflects the bay’s degraded water quality. Although pollution of Guanabara Bay is not a recent problem, the hosting of the 2016 Olympic Games propelled the government to launch a series plans to restore the bay’s water quality. If all plans are fully implemented, the restoration of Guanabara Bay and its shores may be one of the best legacies of the Olympic Games in Rio de Janeiro.

  15. Utilization by fishes of the Alviso Island ponds and adjacent waters in south san francisco bay following restoration to tidal influence

    Science.gov (United States)

    Saiki, M.K.; Mejia, F.H.

    2009-01-01

    Earthen levees of three isolated salt ponds known locally as the Alviso Island Ponds were intentionally breached in March 2006 to allow tidal exchange of the ponds with water from Coyote Creek. The water exchange transformed the previously fishless hypersaline ponds into lower salinity habitats suitable for fish life. This study documented fish utilization of the ponds, adjacent reaches of Coyote Creek, and an upstream reach in nearby Artesian Slough during May-July 2006. By the time the study was initiated, water quality conditions in the ponds were similar to conditions in adjacent reaches of Coyote Creek. The only variable exhibiting a strong gradient within the study area was salinity, which increased progressively from upstream to downstream in Coyote Creek. A total of 4,034 fish represented by 18 species from 14 families was caught during the study. Judging from cluster analysis of presence-absence data that excluded rare fish species, the 10 sampling units (3 ponds, 6 reaches in Coyote Creek, and 1 reach in Artesian Slough) formed two clusters or groups, suggesting two species assemblages. The existence of two groups was also suggested by ordination with non-metric multidimensional scaling (NMS). One group, which was composed of the three ponds and four of the lowermost reaches of Coyote Creek, was characterized by mostly estuarine or marine species (e.g., topsmelt, Atherinops affinis; northern anchovy, Engraulis mordax; and longjaw mudsucker, Gillichthys mirabilis). The second group, which was composed of the two uppermost reaches of Coyote Creek and the one reach of Artesian Slough, was characterized by freshwater species (e.g., Sacramento sucker, Catostomus occidentalis) and by an absence of the estuarine/marine species noted in the first assemblage. Judging from a joint plot of selected water quality variables overlaying the ordination results, salinity was the only important variable associated with spatial distribution of fish species. Water

  16. MODEL PREDIKSI PENGARUH LIMBAH CAIR HOTEL TERHADAP KUALITAS AIR LAUT DI PESISIR TELUK KUPANG (A Prediction Model of Liquid Waste Hotel Impact on The Sea Water along The Coast of Kupang Bay

    Directory of Open Access Journals (Sweden)

    Inty Megarini

    2015-11-01

    Full Text Available ABSTRAK Hotel-hotel di pesisir Teluk Kupang sebagian besar membuang efluen limbah cairnya ke laut. Kondisi ini akan berpengaruh terhadap kualitas air laut dan berdampak pada kelangsungan hidup biota dan mikroorganisme laut. Penelitian ini bertujuan untuk membuat prediksi pengaruh efluen limbah cair hotel yang dibuang terhadap kualitas air laut di hadapannya. Parameter yang diteliti adalah minyak dan lemak dan ortofosfat efluen limbah cair hotel. Parameter kualitas air laut yang diteliti adalah kekeruhan, minyak dan lemak dan klorofil. Metode pengambilan sampel dan pengujian menggunakan SNI dan USEPA. Analisis data menggunakan uji korelasi dan regresi. Hasil penelitian menunjukkan bahwa kekeruhan air laut pada jarak 0 meter dan 25 meter dapat diprediksi dari kadar minyak dan lemak efluen limbah cair hotel melalui model regresi y = 0,0051 x + 4,8456 dan y = 0,0015 x + 4,5440. Kadar klorofil air laut pada jarak 25 meter dan 75 meter dapat diprediksi dari kadar ortofosfat efluen limbah cair hotel melalui persamaan regresi y = 0,0430 x + 0,0004 dan y = 0,0075 x + 0,0001. ABSTRACT Most of the hotels located along the coast of Kupang Bay dump their effluent liquid waste to the sea. This action will definitely affect the sea water quality and in turn, will unavoidably give deep impact on the life of both microorganism and all the living things in the sea. This research intends to make an impact prediction on the sea water quality over the dumping hotels’ affluent liquid waste to the sea. The parameters which are observed are oil and fat and orthophosphate of the hotels’ affluent liquid waste. While the observed parameters of the sea water quality are turbidity, oil and fat, and chlorophyll. The methods used to take and test the sample are SNI and USEPA. And to analyze the data, testing on both correlation and regression are applied. The result of the study reveals that the turbidity of the sea water within the range of 0 to 25 meters can be

  17. Ecological Environment Quality Assessment on Petrochemical Sewage Discharge Waters of Daya Bay in Winter%大亚湾石化排污区海域冬季生态环境质量评价

    Institute of Scientific and Technical Information of China (English)

    徐娇娇; 徐姗楠; 李纯厚; 刘永; 林琳

    2013-01-01

    Daya bay,a typical subtropical marine genetic resource pool in the South China Sea,is one of the most important inshore fisheries areas in Guangdong province.However,the marine environments has been threatened and effected by rapid developments of the petrochemical industry in recent years.In current study,the ecological environment quality has been assessed.Based on the ecological and environmental investigation in January 2012,the states of ecological environment quality of the Daya Bay petrochemical sewage discharge waters was assessed with four factors,including sea water quality,nutrient structure and level,sediment quality,primary productivity and food organism level.The comprehensive index method was used for integrated assessment,as well.The results show that most of the water quality factors,including dissolved oxygen,biochemical oxygen demand,chemical oxygen demand,sulfide,phosphorus,dissolved inorganic nitrogen and heavy metals of Cu,Pb and Cd,were all conforming to Grade Ⅱ of the National Sea Water Quality Standard of China.However,some factors,including petroleum hydrocarbon of 66.7% sites,pH of 91.7% sites,and Zn of several sites,exceed the Grade Ⅱ of the National Standard with the average value of water quality comprehensive index at 1.215.The status of above factors consequently reached a low-level pollution without any pollution caused by organic pollutants.What makes unoptimistic is the concentration of nutrients in sea water is relatively high.Fortunately,the quality of sediment is very good and conforming to the Grade Ⅰ of National Marine Sediment Quality Standard,with the com prehensive pollution index at 0.478.Furthermore,the status of primary productivity reached the level of medium because of the high abundance of phytoplankton,zooplankton and benthic.According to the references and data of this study,the investigated petrochemical sewage discharge waters of Daya Bay was slight polluted by total petroleum hydrocarbons (TPHs

  18. The Liverpool Bay Coastal Observatory

    Science.gov (United States)

    Howarth, John; Palmer, Matthew

    2011-11-01

    A pilot Coastal Observatory has been established in Liverpool Bay which integrates (near) real-time measurements with coupled models and whose results are displayed on the web. The aim is to understand the functioning of coastal seas, their response to natural forcing and the consequences of human activity. The eastern Irish Sea is an apt test site, since it encompasses a comprehensive range of processes found in tidally dominated coastal seas, including near-shore physical and biogeochemical processes influenced by estuarine inflows, where both vertical and horizontal gradients are important. Applications include hypernutrification, since the region receives significantly elevated levels of nutrient inputs, shoreline management (coastal flooding and beach erosion/accretion), and understanding present conditions to predict the impact of climate change (for instance if the number and severity of storms, or of high or low river flows, change). The integrated measurement suite which started in August 2002 covers a range of space and time scales. It includes in situ time series, four to six weekly regional water column surveys, an instrumented ferry, a shore-based HF radar system measuring surface currents and waves, coastal tide gauges and visible and infra-red satellite data. The time series enable definition of the seasonal cycle, its inter-annual variability and provide a baseline from which the relative importance of events can be quantified. A suite of nested 3D hydrodynamic, wave and ecosystem models is run daily, focusing on the observatory area by covering the ocean/shelf of northwest Europe (at 12-km resolution) and the Irish Sea (at 1.8 km), and Liverpool Bay at the highest resolution of 200 m. The measurements test the models against events as they happen in a truly 3D context. All measurements and model outputs are displayed freely on the Coastal Observatory website (http://cobs.pol.ac.uk) for an audience of researchers, education, coastal managers and the

  19. DEVELOP Chesapeake Bay Watershed Hydrology - UAV Sensor Web

    Science.gov (United States)

    Holley, S. D.; Baruah, A.

    2008-12-01

    The Chesapeake Bay is the largest estuary in the United States, with a watershed extending through six states and the nation's capital. Urbanization and agriculture practices have led to an excess runoff of nutrients and sediment into the bay. Nutrients and sediment loading stimulate the growth of algal blooms associated with various problems including localized dissolved oxygen deficiencies, toxic algal blooms and death of marine life. The Chesapeake Bay Program, among other stakeholder organizations, contributes greatly to the restoration efforts of the Chesapeake Bay. These stakeholders contribute in many ways such as monitoring the water quality, leading clean-up projects, and actively restoring native habitats. The first stage of the DEVELOP Chesapeake Bay Coastal Management project, relating to water quality, contributed to the restoration efforts by introducing NASA satellite-based water quality data products to the stakeholders as a complement to their current monitoring methods. The second stage, to be initiated in the fall 2008 internship term, will focus on the impacts of land cover variability within the Chesapeake Bay Watershed. Multiple student led discussions with members of the Land Cover team at the Chesapeake Bay Program Office in the DEVELOP GSFC 2008 summer term uncovered the need for remote sensing data for hydrological mapping in the watershed. The Chesapeake Bay Program expressed in repeated discussions on Land Cover mapping that significant portions of upper river areas, streams, and the land directly interfacing those waters are not accurately depicted in the watershed model. Without such hydrological mapping correlated with land cover data the model will not be useful in depicting source areas of nutrient loading which has an ecological and economic impact in and around the Chesapeake Bay. The fall 2008 DEVELOP team will examine the use of UAV flown sensors in connection with in-situ and Earth Observation satellite data. To maximize the

  20. 辽东湾北部近海大型水母数量分布和温度盐度特征%THE QUANTITY DISTRIBUTION OF GIANT JELLYFISH AND ITS RELATIONSHIP TO SEAWATER TEMPERATURE AND SALINITY IN INSHORE WATERS OF THE NORTHERN LIAODONG BAY REGION

    Institute of Scientific and Technical Information of China (English)

    王彬; 董婧; 王文波; 李玉龙; 李轶平; 刘修泽; 付杰

    2012-01-01

    The distribution of giant jellyfish and the ecological type were analyzed on the basis of the sampling data obtained during the surveys in inshore waters within 10m isobath of the northern Liaodong Bay, Bohai Sea from late May to late July from 2009 to 2011. There were four main species of giant jellyfish, Rhopilema esculentum, Nemopilema no- mural, Cyanea nozakii and Aurelia sp.1. The larval medusae of R. esculentum was mainly found within 5m isobath in coastal estuaries of the northern Liaodong Bay, and adult medusae was mainly found in both sides of the waters near 5m isobath. The adult had a slightly tendency to go to deep waters or low jellyfish catch density waters with the individual increasing. The relatively high temperature and low salinity area of coastal estuaries was an optimum environment for the growth of R. esculentum. There were a large amount of larval medusae of N. nomurai in inshore waters of northern Liaodong Bay in June, and the amount ofN. nomurai decreased a lot with the individual increasing in the area in July. Au- relia sp.1 mainly inhabitated in the southern Liaodong Bay, and was found a few in inshore waters of the northern Liaodong Bay in 2010 and 2011. C. nozakii inhabitated in high salinity area, and was few found in Liaodong Bay in recent years. Among giant jelly- fishes in Liaodong Bay, N. nomurai grew more quickly. The occurrence time of the larval medusa ofR. esculentum and N. nomurai in Liaodong Bay was later than in the Yellow Sea and East China Sea.%通过2009--2011年5月下旬-7月下旬辽东湾北部近海10m等深线内的大型水母调查数据.分析了辽东湾北部近海近三年中大型水母资源状况,并探讨了辽东湾大型水母的生态类型。结果显示:辽东湾北部近海大型水母种类主要有海蜇(Rhopilema esculentum)、沙蜇(Nemopilema nomurai)、白色霞水母(Cyaneanozakii)、海月水母(Aureliasp.1),海蜇和沙蜇是优势种。海蜇幼水

  1. Rapid fluctuations in flow and water-column properties in Asan Bay, Guam: implications for selective resilience of coral reefs in warming seas

    Science.gov (United States)

    Storlazzi, C.D.; Field, M.E.; Cheriton, O.M.; Presto, M.K.; Logan, J.B.

    2013-01-01

    Hydrodynamics and water-column properties were investigated off west-central Guam from July 2007 through January 2008. Rapid fluctuations, on time scales of 10s of min, in currents, temperature, salinity, and acoustic backscatter were observed to occur on sub-diurnal frequencies along more than 2 km of the fore reef but not at the reef crest. During periods characterized by higher sea-surface temperatures (SSTs), weaker wind forcing, smaller ocean surface waves, and greater thermal stratification, rapid decreases in temperature and concurrent rapid increases in salinity and acoustic backscatter coincided with onshore-directed near-bed currents and offshore-directed near-surface currents. During the study, these cool-water events, on average, lasted 2.3 h and decreased the water temperature 0.57 °C, increased the salinity 0.25 PSU, and were two orders of magnitude more prevalent during the summer season than the winter. During the summer season when the average satellite-derived SST anomaly was +0.63 °C, these cooling events, on average, lowered the temperature 1.14 °C along the fore reef but only 0.11 °C along the reef crest. The rapid shifts appear to be the result of internal tidal bores pumping cooler, more saline, higher-backscatter oceanic water from depths >50 m over cross-shore distances of 100 s of m into the warmer, less saline waters at depths of 20 m and shallower. Such internal bores appear to have the potential to buffer shallow coral reefs from predicted increases in SSTs by bringing cool, offshore water to shallow coral environments. These cooling internal bores may also provide additional benefits to offset stress such as supplying food to thermally stressed corals, reducing stress due to ultraviolet radiation and/or low salinity, and delivering coral larvae from deeper reefs not impacted by surface thermal stress. Thus, the presence of internal bores might be an important factor locally in the resilience of select coral reefs facing increased

  2. Remarks on kernel Bayes' rule

    OpenAIRE

    Johno, Hisashi; Nakamoto, Kazunori; Saigo, Tatsuhiko

    2015-01-01

    Kernel Bayes' rule has been proposed as a nonparametric kernel-based method to realize Bayesian inference in reproducing kernel Hilbert spaces. However, we demonstrate both theoretically and experimentally that the prediction result by kernel Bayes' rule is in some cases unnatural. We consider that this phenomenon is in part due to the fact that the assumptions in kernel Bayes' rule do not hold in general.

  3. Daya Bay Antineutrino Detector Gas System

    CERN Document Server

    Band, H R; Chu, M-C; Heeger, K M; Kwok, M W; Shih, K; Wise, T; Xiao, Q

    2012-01-01

    The Daya Bay Antineutrino Detector gas system is designed to protect the liquid scintillator targets of the antineutrino detectors against degradation and contamination from exposure to ambient laboratory air. The gas system is also used to monitor the leak tightness of the antineutrino detector assembly. The cover gas system constantly flushes the gas volumes above the liquid scintillator with dry nitrogen to minimize oxidation of the scintillator over the five year lifetime of the experiment. This constant flush also prevents the infiltration of radon or other contaminants into these detecting liquids keeping the internal backgrounds low. Since the Daya Bay antineutrino detectors are immersed in the large water pools of the muon veto system, other gas volumes are needed to protect vital detector cables or gas lines. These volumes are also purged with dry gas. Return gas is monitored for oxygen content and humidity to provide early warning of potentially damaging leaks. The design and performance of the Daya...

  4. BCDC Bay Trail Alignment 2009

    Data.gov (United States)

    California Department of Resources — The Bay Trail provides easily accessible recreational opportunities for outdoor enthusiasts, including hikers, joggers, bicyclists and skaters. It also offers a...

  5. BCDC Bay Trail Alignment 2009

    Data.gov (United States)

    California Department of Resources — The Bay Trail provides easily accessible recreational opportunities for outdoor enthusiasts, including hikers, joggers, bicyclists and skaters. It also offers a...

  6. Distribution of mercury in surficial sediments from Todos Santos Bay, Baja California, México.

    Science.gov (United States)

    Gutiérrez-Galindo, E A; Casas-Beltrán, D A; Muñoz-Barbosa, A; Daesslé, L W; Segovia-Zavala, J A; Macías-Zamora, J V; Orozco-Borbón, M V

    2008-02-01

    During 2004 the spatial distribution of total Hg in sediments from Todos Santos Bay, Baja California, México was studied to evaluate the degree of environmental impact in this bay. The results showed low concentrations and no Hg enrichment at any site. These findings suggest natural levels of Hg in the water of Todos Santos Bay. The regional distribution of Hg/Fe shows lower values in the East and higher in the West of the bay. No significant correlations (p<0.05) were found between Hg and organic matter or particle size, suggesting that the distribution of Hg is not controlled by these variables.

  7. U.S. Geological Survey Science—Improving the value of the Chesapeake Bay watershed

    Science.gov (United States)

    Phillips, Scott W.; Hyer, Kenneth; Goldbaum, Elizabeth

    2017-05-05

    IntroductionCongress directed the Federal Government to work with States to restore the Nation’s largest estuary.Chesapeake Bay restoration provides important economic and ecological benefits:18 million people live and work in the Bay watershed and enjoy its benefits.3,600 types of fish, wildlife, and plants underpin the economic value of the Bay ecosystem.Poor water quality and habitat loss threaten restoration and negatively impact the economy.10 Goals to meet by 2025 through the Chesapeake Bay Program, a voluntary partnership.

  8. Distribution Pattern of Heavy Metals in the Surface Sediments of the Jiaozhou Bay

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Grain size analysis and chemical analysis of heavy metals are made for 312 surface samples of the Jiaozhou Bay. Nineteen samples of the waste water taken from the sewage discharge outlets along the eastern coast of the bay are also analyzed for heavy metals. Results show that heavy metals are richer in the east and poorer in the west of the bay. Sedimentary dynamic studies reveal that the distribution of heavy metals in the surface sediments of the Jiaozhou Bay is under the control of hydrodynamics.

  9. Temperature and Salinity in Kaneohe Bay, Oahu, Hawaii 2005 - 2007 in Support of Fresh Water Plume Studies Performed by the Department of Oceanography at the Univesity of Hawaii (NODC Accession 0039532)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Freshwater plumes from rain run-off into Kaneohe Bay are the focus for the investigation. Measurements of temperature and salinity from a moored, fixed-level CTD and...

  10. Processed Continuous Resistivity Profile (CRP) Data Below the Sediment Water Interface From the Potomac River/Chesapeake Bay collected from Sept. 6, 2006 to Sept. 8, 2006 on USGS Cruise 06018 (MRG2006_ALLZYZ.SHP)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — In order to test hypotheses about groundwater flow under and into Chesapeake Bay, geophysical surveys were conducted by U.S. Geological Survey (USGS) scientists on...

  11. Impact of Point and Non-point Source Pollution on Coral Reef Ecosystems In Mamala Bay, Oahu, Hawaii based on Water Quality Measurements and Benthic Surveys in 1993-1994 (NODC Accession 0001172)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The effects of both point and non-point sources of pollution on coral reef ecosystems in Mamala Bay were studied at three levels of biological organization; the...

  12. The experimental studies of influence of hydrogen sulfide on species of eelgrass (Zostera japonica and Zostera marina) in Padilla Bay, coastal waters of southeast Alaska conducted from 2013-06-01 to 2013-09-30 (NCEI Accession 0137907)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Two species of eelgrass can be found in Padilla Bay, Washington (Zostera japonica and Zostera marina) and act as a bioindicators of ecosystem health. Many factors...

  13. Currents in Kaneohe Bay, Oahu, Hawaii 2005 - 2007 in Support of Fresh Water Plume Studies Performed by the Department of Oceanography at the Univesity of Hawaii (NODC Accession 0040251)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Freshwater plumes from rain run-off into Kaneohe Bay is the focus for the investigation. Measurements in this data set are currents as measured by an moored Acoustic...

  14. Processed Continuous Resistivity Profile (CRP) Data Below the Sediment Water Interface From the Potomac River/Chesapeake Bay collected from Sept. 6, 2006 to Sept. 8, 2006 on USGS Cruise 06018 (MRG2006_ALLZYZ.SHP)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — In order to test hypotheses about groundwater flow under and into Chesapeake Bay, geophysical surveys were conducted by U.S. Geological Survey (USGS) scientists on...

  15. Preliminary assessment of the effects of Delaware Bay water and a known endocrine disrupting compound on horseshoe crabs (Limulus polyphemus) using proteomics and observation of embryonic development and survival

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The eggs, larvae, and juveniles of horseshoe crabs (L. polyphemus) contribute significantly to the forage base of many species in Delaware Bay. The eggs also provide...

  16. Two 24-hour Studies of Water Quality in the Ala Wai Canal during March and July, 1994 for the Mamala Bay Study, Pollutant Source Identification Project MB-3 (NODC Accession 0001188)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Pollutant Source Identification Project (MB-3) sought to provide a summary and analysis of pollutant loads to Mamala Bay from both point and nonpoint sources....

  17. 33 CFR 167.173 - Off Delaware Bay: Two-Way Traffic Route.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Off Delaware Bay: Two-Way Traffic... SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY OFFSHORE TRAFFIC SEPARATION SCHEMES Description of Traffic Separation Schemes and Precautionary Areas Atlantic East Coast § 167.173 Off Delaware Bay: Two-Way Traffic...

  18. A comparative study of vertical stabilities in the Arabian sea and Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sastry, J.S.; Rao, D.P.

    Stabilities in the upper 300 m in the Arabian Sea and the Bay of Bengal are computed and presented seasonwise. The water column in the Bay of Bengal is more strongly stratified than that in the Arabian Sea. These studies suggest that the vertical...

  19. 33 CFR 334.390 - Atlantic Ocean south of entrance to Chesapeake Bay; firing range.

    Science.gov (United States)

    2010-07-01

    ... to Chesapeake Bay; firing range. 334.390 Section 334.390 Navigation and Navigable Waters CORPS OF....390 Atlantic Ocean south of entrance to Chesapeake Bay; firing range. (a) The danger zone. A section... four (4) nautical miles. (3) Firing on the ranges will be suspended as long as any vessel is within...

  20. Radium mass balance and submarine groundwater discharge in Sepetiba Bay, Rio de Janeiro State, Brazil

    Science.gov (United States)

    Smoak, Joseph M.; Sanders, Christian J.; Patchineelam, Sambasiva R.; Moore, Willard S.

    2012-11-01

    Radium-226 and 228Ra activities were determined in water samples from within and adjacent to Sepetiba Bay, Rio de Janeiro State (Brazil) in 1998, 2005 and 2007. Surface waters in Sepetiba Bay were substantially higher in 226Ra and 228Ra compared to ocean end member samples. Using the residence time of water in the bay we calculated the flux required to maintain the observed enrichment over the ocean end members. We then applied a radium mass balance to estimate the volume of submarine groundwater discharge (SGD) into the bay. The estimates of SGD into Sepetiba Bay (in 1010 L day-1) were 2.56, 3.75, and 1.0, respectively for 1998, 2005, and 2007. These estimates are equivalent to approximately 1% of the total volume of the bay each day or 50 L m-2 day-1. It is likely that a substantial portion of the SGD in Sepetiba Bay consists of infiltrated seawater. This large flux of SGD has the potential to supply substantial quantities of nutrients, carbon and metals into coastal waters. The SGD found here is greater than what is typically found in SGD studies along the eastern United States and areas with similar geologic characteristics. Considering there are many coastal areas around the world like Sepetiba Bay, this could revise upward the already important contribution of SGD to coastal as well as oceanic budgets.