Organic Carbon Burial Rates in Mangrove Soils Along Florida's Coast from Tampa Bay to Biscayne National Park

Science.gov (United States)

Smoak, J. M.; Breithaupt, J. L.; Moyer, R. P.; Sanders, C. J.; Proctor, M. R.; Jacobs, J. A.; Chappel, A. R.; Comparetto, K. R.

2016-12-01

Mangrove forests provide a range of valuable ecosystem services including sequestering organic carbon (OC) in their soils at rates much greater on a per area basis than those found in other types of forests. This restricts a large quantity of OC to a relatively small area along tropical and sub-tropical coastal margins, where dramatic climate-driven impacts are expected. Hence this small yet highly-vulnerable area will have a disproportionally large impact on global carbon cycling. One of the fundamental climate-related questions in mangrove systems is whether their soils will continue to function as a globally significant OC sink or become a source as previously buried OC is oxidized and returned to the atmosphere. While changes to precipitation, temperature, cyclone activity, etc. may influence this sink capacity, it is accelerating sea-level rise (SLR) that is of greatest immediate concern because if mangrove peat formation fails to keep pace then all ecosystem services, including carbon burial, will collapse. Mangroves that receive minimal terrigenous sediments (such as those in South Florida) are largely dependent on the rate of OC accumulation as a key contributor to accretion. To investigate these processes, we measured OC burial and accretion rates over the last 100 years (via 210Pb dating) from sites in Tampa Bay, Charlotte Harbor, Ten Thousand Islands, Everglades National Park, Biscayne National Park, and the Lower Florida Keys. The mean 100-year burial rate over all sites is 119 ± 33 (SD) g m-2 yr-1 which is lower than the global mean. Mean accretion rates were found to match (within error) the relatively modest average SLR over the last 100 years, but rates may not have kept pace with the substantially higher SLR in the last decade. This investigation contributes to establishing regional-scale Blue Carbon budgets, and examines how OC burial in mangroves has changed over the last 100 years. This improved understanding of past mangrove OC burial response

Evaluation of the effects of sea-level change and coastal canal management on saltwater intrusion in the Biscayne aquifer of south Florida, USA

Science.gov (United States)

Hughes, J. D.; Sifuentes, D. F.; White, J.

2015-12-01

Sea-level increases are expected to have an effect on the position of the freshwater-saltwater interface in the Biscayne aquifer in south Florida as a result of the low topographic relief of the area and high rates of groundwater withdrawal from the aquifer. To study the effects that future sea-level increases will have on saltwater intrusion in the Biscayne aquifer in Broward County, Florida, a three-dimensional, variable-density, groundwater-flow and transport model was developed. The model was calibrated to observed groundwater heads and chloride concentrations for a 62-year period that includes historic increases in sea level, development of a surface-water management system to control flooding, and increases in groundwater withdrawals as the area transitioned from agricultural to urban land uses. Sensitivity analyses indicate that downward leakage of saltwater from coastal canals and creeks was the primary source of saltwater to the Biscayne aquifer during the last 62-years in areas where the surface-water system is not actively managed and is tidally influenced. In areas removed from the coastal canals and creeks or under active surface-water management, historic groundwater withdrawals were the primary cause of saltwater intrusion into the aquifer. Simulation of future conditions suggests that possible increases in sea level will result in additional saltwater intrusion. Model scenarios suggest that additional saltwater intrusion will be greatest in areas where coastal canals and creeks were historically the primary source of seawater. Future saltwater intrusion in those areas, however, may be reduced by relocation of salinity-control structures.

The onset of deglaciation of Cumberland Bay and Stromness Bay, South Georgia

NARCIS (Netherlands)

Van Der Putten, N.; Verbruggen, C.

Carbon dating of basal peat deposits in Cumberland Bay and Stromness Bay and sediments from a lake in Stromness Bay, South Georgia indicates deglaciation at the very beginning of the Holocene before c. 9500 14C yr BP. This post-dates the deglaciation of one local lake which has been ice-free since

South Bay Salt Pond Mercury Studies Project

Science.gov (United States)

Information about the SFBWQP South Bay Salt Pond Mercury Studies Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

The critical role of islands for waterbird breeding and foraging habitat in managed ponds of the South Bay Salt Pond Restoration Project, South San Francisco Bay, California

Science.gov (United States)

Ackerman, Joshua T.; Hartman, C. Alex; Herzog, Mark P.; Smith, Lacy M.; Moskal, Stacy M.; De La Cruz, Susan E. W.; Yee, Julie L.; Takekawa, John Y.

2014-01-01

The South Bay Salt Pond Restoration Project aims to restore 50–90 percent of former salt evaporation ponds into tidal marsh in South San Francisco Bay, California. However, large numbers of waterbirds use these ponds annually as nesting and foraging habitat. Islands within ponds are particularly important habitat for nesting, foraging, and roosting waterbirds. To maintain current waterbird populations, the South Bay Salt Pond Restoration Project plans to create new islands within former salt ponds in South San Francisco Bay. In a series of studies, we investigated pond and individual island attributes that are most beneficial to nesting, foraging, and roosting waterbirds.

The `Henry Problem' of `density-driven' groundwater flow versus Tothian `groundwater flow systems' with variable density: A review of the influential Biscayne aquifer data.

Science.gov (United States)

Weyer, K. U.

2017-12-01

Coastal groundwater flow investigations at the Biscayne Bay, south of Miami, Florida, gave rise to the concept of density-driven flow of seawater into coastal aquifers creating a saltwater wedge. Within that wedge, convection-driven return flow of seawater and a dispersion zone were assumed by Cooper et al. (1964) to be the cause of the Biscayne aquifer `sea water wedge'. This conclusion was based on the chloride distribution within the aquifer and on an analytical model concept assuming convection flow within a confined aquifer without taking non-chemical field data into consideration. This concept was later labelled the `Henry Problem', which any numerical variable density flow program must be able to simulate to be considered acceptable. Both, `density-driven flow' and Tothian `groundwater flow systems' (with or without variable density conditions) are driven by gravitation. The difference between the two are the boundary conditions. 'Density-driven flow' occurs under hydrostatic boundary conditions while Tothian `groundwater flow systems' occur under hydrodynamic boundary conditions. Revisiting the Cooper et al. (1964) publication with its record of piezometric field data (heads) showed that the so-called sea water wedge has been caused by discharging deep saline groundwater driven by gravitational flow and not by denser sea water. Density driven flow of seawater into the aquifer was not found reflected in the head measurements for low and high tide conditions which had been taken contemporaneously with the chloride measurements. These head measurements had not been included in the flow interpretation. The very same head measurements indicated a clear dividing line between shallow local fresh groundwater flow and saline deep groundwater flow without the existence of a dispersion zone or a convection cell. The Biscayne situation emphasizes the need for any chemical interpretation of flow pattern to be supported by head data as energy indicators of flow fields

Continuous resistivity profiling data from Great South Bay, Long Island, New York

Science.gov (United States)

Cross, V.A.; Bratton, J.F.; Kroeger, K.D.; Crusius, John; Worley, C.R.

2013-01-01

An investigation of submarine aquifers adjacent to the Fire Island National Seashore and Long Island, New York was conducted to assess the importance of submarine groundwater discharge as a potential nonpoint source of nitrogen delivery to Great South Bay. Over 200 kilometers of continuous resistivity profiling data were collected to image the fresh-saline groundwater interface in sediments beneath the bay. In addition, groundwater sampling was performed at sites (1) along the north shore of Great South Bay, particularly in Patchogue Bay, that were representative of the developed Long Island shoreline, and (2) at sites on and adjacent to Fire Island, a 50-kilometer-long barrier island on the south side of Great South Bay. Other field activities included sediment coring, stationary electrical resistivity profiling, and surveys of in situ pore water conductivity. Results of continuous resistivity profiling surveys are described in this report. The onshore and offshore shallow hydrostratigraphy of the Great South Bay shorelines, particularly the presence and nature of submarine confining units, appears to exert primary control on the dimensions and chemistry of the submarine groundwater flow and discharge zones. Sediment coring has shown that the confining units commonly consist of drowned and buried peat layers likely deposited in salt marshes. Low-salinity groundwater extends from 10 to 100 meters offshore along much of the north and south shores of Great South Bay based on continuous resistivity profiling data, especially off the mouths of tidal creeks and beneath shallow flats to the north of Fire Island adjacent to modern salt marshes. Human modifications of much of the shoreline and nearshore areas along the north shore of the bay, including filling of salt marshes, construction of bulkheads and piers, and dredging of navigation channels, has substantially altered the natural hydrogeology of the bay's shorelines by truncating confining units and increasing

South Bay Salt Pond Restoration, Phase II at Ravenswood

Science.gov (United States)

Information about the South Bay Salt Pond Restoration Project: Phase II Construction at Ravenswood, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

Water quality in South San Francisco Bay, California: current condition and potential issues for the South Bay Salt Pond Restoration Project.

Science.gov (United States)

Grenier, J Letitia; Davis, Jay A

2010-01-01

The SBSPRP is an extensive tidal wetland restoration project that is underway at the margin of South San Francisco Bay, California. The Project, which aims to restore former salt ponds to tidal marsh and manage other ponds for water bird support, is taking place in the context of a highly urbanized watershed and an Estuary already impacted by chemical contaminants. There is an intimate relationship between water quality in the watershed, the Bay, and the transitional wetland areas where the Project is located. The Project seeks to restore habitat for endangered and endemic species and to provide recreational opportunities for people. Therefore, water quality and bioaccumulation of contaminants in fish and wildlife is an important concern for the success of the Project. Mercury, PCBs, and PBDEs are the persistent contaminants of greatest concern in the region. All of these contaminants are present at elevated concentrations both in the abiotic environment and in wildlife. Dioxins, pyrethroids, PAHs, and selenium are also problematic. Organochlorine insecticides have historically impacted the Bay, and they remain above thresholds for concern in a small proportion of samples. Emerging contaminants, such as PFCs and non-PBDE flame retardants, are also an important water quality issue. Beyond chemical pollutants, other concerns for water quality in South San Francisco Bay exist, and include biological constituents, especially invasive species, and chemical attributes, such as dissolved oxygen and salinity. Future changes, both from within the Project and from the Bay and watershed, are likely to influence water quality in the region. Project actions to restore wetlands could worsen, improve, or not affect the already impaired water quality in South Bay. Accelerated erosion of buried sediment as a consequence of Project restoration actions is a potentially serious regional threat to South Bay water and sediment quality. Furthermore, the planned restoration of salt ponds

Faunal and vegetation monitoring in response to harbor dredging in the Port of Miami

Science.gov (United States)

Daniels, Andre; Stevenson, Rachael; Smith, Erin; Robblee, Michael

2018-04-11

Seagrasses are highly productive ecosystems. A before-after-control-impact (BACI) design was used to examine effects of dredging on seagrasses and the animals that inhabit them. The control site North Biscayne Bay and the affected site Port of Miami had seagrass densities decrease during both the before, Fish and Invertebrate Assessment Network 2006-2011, and after, Faunal Monitoring in Response to Harbor Dredging 2014-2016, studies. Turbidity levels increased at North Biscayne Bay and Port of Miami basins during the Faunal Monitoring in Response to Harbor Dredging study, especially in 2016. Animal populations decreased significantly in North Biscayne Bay and Port of Miami in the Faunal Monitoring in Response to Harbor Dredging study compared to the Fish and Invertebrate Assessment Network study. Predictive modeling shows that numbers of animal populations will likely continue to decrease if the negative trends in seagrass densities continue unabated. There could be effects on several fisheries vital to the south Florida economy. Additional research could determine if animal populations and seagrass densities have rebounded or continued to decrease.

South Bay Salt Pond Tidal Wetland Restoration Phase II Planning

Science.gov (United States)

Information about the SFBWQP South Bay Salt Pond Tidal Wetland Restoration Phase II Planning project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic re

Recolonisation of the Robberg Peninsula (Plettenberg Bay, South ...

African Journals Online (AJOL)

The Cape fur seal Arctocephalus pusillus pusillus colony at Robberg Peninsula, Plettenberg Bay, on the south-east coast of South Africa, was driven to extinction by indiscriminate harvesting by the late 1800s. Seals only began to recolonise this site in the 1990s. This study describes the recolonisation process from 2000 to ...

Shallow-water, nearshore current dynamics in Algoa Bay, South ...

African Journals Online (AJOL)

Nearshore currents play a vital role in the transport of eggs and larval stages of fish. However, little is known about their complexity and the implications for dispersal of fish larvae. The study describes the complexity of the shallow nearshore environment in eastern Algoa Bay, on the south-east coast of South Africa, and its ...

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.

33 CFR 162.65 - All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary...

Science.gov (United States)

2010-07-01

... Atlantic Ocean south of Chesapeake Bay and all waterways tributary to the Gulf of Mexico east and south of... All waterways tributary to the Atlantic Ocean south of Chesapeake Bay and all waterways tributary to..., which are tributary to or connected by other waterways with the Atlantic Ocean south of Chesapeake Bay...

76 FR 31851 - Safety Zone; Put-in-Bay Fireworks, Fox's the Dock Pier; South Bass Island, Put-in-Bay, OH

Science.gov (United States)

2011-06-02

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2011-0417] RIN 1625-AA00 Safety Zone; Put-in-Bay Fireworks, Fox's the Dock Pier; South Bass Island, Put-in-Bay, OH AGENCY.... Add Sec. 165.T09-0417 as follows: Sec. 165.T09-0417 Safety Zone; Put-In-Bay Fireworks, Fox's the Dock...

South Bay Salt Pond Tidal Marsh Restoration at Pond A17 Project

Science.gov (United States)

Information about the SFBWQP South Bay Salt Pond Tidal Marsh Restoration at Pond A17 Project, part of an EPA competitive grant program to improve SF Bay water quality focused on restoring impaired waters and enhancing aquatic resources.

76 FR 70480 - Otay River Estuary Restoration Project, South San Diego Bay Unit of the San Diego Bay National...

Science.gov (United States)

2011-11-14

... River Estuary Restoration Project, South San Diego Bay Unit of the San Diego Bay National Wildlife...), intend to prepare an environmental impact statement (EIS) for the proposed Otay River Estuary Restoration... any one of the following methods. Email: [email protected] . Please include ``Otay Estuary NOI'' in the...

PHYTOPLANKTON - WET WEIGHT and Other Data from UNKNOWN and Other Platforms From North American Coastline-South from 19860301 to 19870228 (NODC Accession 8700360)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — This accession contains chlorophyll data from Biscayne Bay, collected by the University of Miami from March 1986 to February 1987 as part of the assessment of...

Review of suspended sediment in lower South Bay relevant to light attenuation and phytoplankton blooms

Science.gov (United States)

Schoellhamer, David H.; Shellenbarger, Gregory; Downing-Kunz, Maureen; Manning, Andrew J.

2016-01-01

Lower South Bay (LSB), a shallow subembayment of San Francisco Bay (SFB), is situated south of the Dumbarton Bridge, and is surrounded by, and interconnected with, a network of sloughs, marshes, and former salt ponds undergoing restoration (Figure ES.1). LSB receives 120 million gallons per day of treated wastewater effluent from three publicly owned treatment works (POTWs) that service San Jose and the densely populated surrounding region. During the dry season, when flows from creeks and streams are at their minimum, POTW effluent comprises the majority of freshwater flow to Lower South Bay. Although LSB has a large tidal prism, it experiences limited net exchange with the surrounding Bay, because much of the water that leaves on ebb tides returns during the subsequent flood tides. The limited exchange leads to distinctly different biogeochemical conditions in LSB compared to other SFB subembayments, including LSB having the highest nutrient concentrations and highest phytoplankton biomass.

Geologic and hydrogeologic frameworks of the Biscayne aquifer in central Miami-Dade County, Florida

Science.gov (United States)

Wacker, Michael A.; Cunningham, Kevin J.; Williams, John H.

2014-01-01

Evaluations of the lithostratigraphy, lithofacies, paleontology, ichnology, depositional environments, and cyclostratigraphy from 11 test coreholes were linked to geophysical interpretations, and to results of hydraulic slug tests of six test coreholes at the Snapper Creek Well Field (SCWF), to construct geologic and hydrogeologic frameworks for the study area in central Miami-Dade County, Florida. The resulting geologic and hydrogeologic frameworks are consistent with those recently described for the Biscayne aquifer in the nearby Lake Belt area in Miami-Dade County and link the Lake Belt area frameworks with those developed for the SCWF study area. The hydrogeologic framework is characterized by a triple-porosity pore system of (1) matrix porosity (mainly mesoporous interparticle porosity, moldic porosity, and mesoporous to megaporous separate vugs), which under dynamic conditions, produces limited flow; (2) megaporous, touching-vug porosity that commonly forms stratiform groundwater passageways; and (3) conduit porosity, including bedding-plane vugs, decimeter-scale diameter vertical solution pipes, and meter-scale cavernous vugs. The various pore types and associated permeabilities generally have a predictable vertical spatial distribution related to the cyclostratigraphy. The Biscayne aquifer within the study area can be described as two major flow units separated by a single middle semiconfining unit. The upper Biscayne aquifer flow unit is present mainly within the Miami Limestone at the top of the aquifer and has the greatest hydraulic conductivity values, with a mean of 8,200 feet per day. The middle semiconfining unit, mainly within the upper Fort Thompson Formation, comprises continuous to discontinuous zones with (1) matrix porosity; (2) leaky, low permeability layers that may have up to centimeter-scale vuggy porosity with higher vertical permeability than horizontal permeability; and (3) stratiform flow zones composed of fossil moldic porosity, burrow

33 CFR 100.701 - Special Local Regulations; Marine Events in the Seventh Coast Guard District

Science.gov (United States)

2010-07-01

... Racing Association Full Moon Regatta Biscayne Bay Yacht Racing Association Southern Biscayne Bay inside.... Petersburg Demons Landing St. Petersburg FL, All waters within 100 ft of the seawall. St. Pete Grand Prix Air... River, Downtown Jacksonville in the vicinity of Jacksonville Landing between the Main Street Bridge and...

Biscayne National Park study on reef fish community changes over time

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Reef fish assemblage structure was assessed in 20062007 (recent period) in Biscayne National Park, Florida, USA , and compared with data collected from 1977 to 1981...

33 CFR 334.640 - Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. 334.640 Section 334.640 Navigation and Navigable Waters... REGULATIONS § 334.640 Gulf of Mexico south of Apalachee Bay, Fla.; Air Force rocket firing range. (a) The...

Coastal upwelling by wind-driven forcing in Jervis Bay, New South Wales: A numerical study for 2011

Science.gov (United States)

Sun, Youn-Jong; Jalón-Rojas, Isabel; Wang, Xiao Hua; Jiang, Donghui

2018-06-01

The Princeton Ocean Model (POM) was used to investigate an upwelling event in Jervis Bay, New South Wales (SE Australia), with varying wind directions and strengths. The POM was adopted with a downscaling approach for the regional ocean model one-way nested to a global ocean model. The upwelling event was detected from the observed wind data and satellite sea surface temperature images. The validated model reproduced the upwelling event showing the input of bottom cold water driven by wind to the bay, its subsequent deflection to the south, and its outcropping to the surface along the west and south coasts. Nevertheless, the behavior of the bottom water that intruded into the bay varied with different wind directions and strengths. Upwelling-favorable wind directions for flushing efficiency within the bay were ranked in the following order: N (0°; northerly) > NNE (30°; northeasterly) > NW (315°; northwesterly) > NE (45°; northeasterly) > ENE (60°; northeasterly). Increasing wind strengths also enhance cold water penetration and water exchange. It was determined that wind-driven downwelling within the bay, which occurred with NNE, NE and ENE winds, played a key role in blocking the intrusion of the cold water upwelled through the bay entrance. A northerly wind stress higher than 0.3 N m-2 was required for the cold water to reach the northern innermost bay.

Vapor Intrusion Facility Points, South Bay CA, 2014, US EPA Region 9

Data.gov (United States)

U.S. Environmental Protection Agency — POINT locations for the South Bay Vapor Instrusion Sites were derived from the NPL data for Region 9. One site, Philips Semiconductor, was extracted from the...

Trace metal associations in the water column of South San Francisco Bay, California

Science.gov (United States)

Kuwabara, J.S.; Chang, Cecily C.Y.; Cloern, J.E.; Fries, T.L.; Davis, J.A.; Luoma, S.N.

1989-01-01

Spatial distributions of copper (Cu), zinc (Zn) and cadmium (Cd) were followed along a longitudinal gradient of dissolved organic carbon (DOC) in South San Francisco Bay (herein referred to as the South Bay). Dissolved Cu, Zn and Cd concentrations ranged from 24 to 66 nM, from 20 to 107 nM and from 1??2 to 4??7 nM, respectively, in samples collected on five dates beginning with the spring phytoplankton bloom and continuing through summer,1985. Dissolved Cu and Zn concentrations varied indirectly with salinity and directly with DOC concentration which ranged from 2??1 to 4??1 mg l-1. Available thermodynamic data strongly support the hypothesis that Cu speciation may be dominated by association with dissolved organic matter. Analogous control of Zn speciation by organic complexation was, however, not indicated in our computations. Computed free ion activity estimates for Cu, Zn and Cd were of the order of 10-10, 10-8 and 10-10 M, respectively. The availability of these metals may be among the factors regulating the growth of certain phytoplankton species within this region of the estuary. In contrast to dissolved Cu, dissolved Cd was directly related to the concentration of suspended particulate matter, suggesting a source of dissolved Cd coincident with elevated particle concentrations in the South Bay (e.g. runoff and solute desorption). Consistent with work in other estuaries, partitioning of all three trace metals onto suspended particulates was negatively correlated with salinity and positively correlated with increases in particulate organic carbon associated with the phytoplankton bloom. These results for the South Bay indicate that sorption processes influence dissolved concentrations of these trace metals, the degree of this influence varies among metals, and processes controlling metal distribution in this estuary appear to be more element-specific than spatially- or temporally-specific. ?? 1989.

Investigation of Spatial and Temporal Trends in Water Quality in Daya Bay, South China Sea

Science.gov (United States)

Wu, Mei-Lin; Wang, You-Shao; Dong, Jun-De; Sun, Cui-Ci; Wang, Yu-Tu; Sun, Fu-Lin; Cheng, Hao

2011-01-01

The objective is to identify the spatial and temporal variability of the hydrochemical quality of the water column in a subtropical coastal system, Daya Bay, China. Water samples were collected in four seasons at 12 monitoring sites. The Southeast Asian monsoons, northeasterly from October to the next April and southwesterly from May to September have also an important influence on water quality in Daya Bay. In the spatial pattern, two groups have been identified, with the help of multidimensional scaling analysis and cluster analysis. Cluster I consisted of the sites S3, S8, S10 and S11 in the west and north coastal parts of Daya Bay. Cluster I is mainly related to anthropogenic activities such as fish-farming. Cluster II consisted of the rest of the stations in the center, east and south parts of Daya Bay. Cluster II is mainly related to seawater exchange from South China Sea. PMID:21776234

Account of the littoral diatoms from Langebaan, Saldanha bay, Cape province, South Africa

CSIR Research Space (South Africa)

Giffen, MH

1975-01-01

Full Text Available collec ted in a small bay near the holiday resort of Langebaan (long. 18,02 E, lat. 33,05 5) on the eastern shore of Saldanha Bay. Saldanha Bay is situated on the western coast of South Africa some 110 km north of Cape Town, and forms a long narrow... per annum about 79% during April to September (i.e. winter rainfall). The region can therefore be regarded as semi-desert. The salinity of the sea water at Langebaan was 35 0/00. The average temperature range of the air in summer is from 16.5? C...

Upwelling and ocean structures off Algoa Bay and the south-east ...

African Journals Online (AJOL)

This situation is investigated off Algoa Bay and along the south-east coast to Port Alfred, where measurements demonstrate that marked temperature variability occurs at the coastline, particularly in summer when temperature structures are more intense and easterly-component winds more common. There is no indication ...

Paleomagnetic investigation of late Quaternary sediments of south San Francisco Bay, California

Science.gov (United States)

Hillhouse, John W.

1977-01-01

Paleomagnetic inclinations of the Late Quaternary sediments of South San Francisco Bay were determined from bore hole samples collected near Dumbarton Bridge. The sediments consist of estuarine muds and nonmarine sand deposits, floored by bedrock of the Mesozoic Franciscan Formation. - Beneath Dumbarton Bridge the entire sedimentary fill is normally polarized; therefore, the fill postdates the Brunhes-Matayama polarity reversal (700,000 y. B.P.). Magnetic time lines such as the Mono Lake excursion (24,000 y. B.P.) and the reversed Blake event (110,000 y B.P.) were not found in this bore hole. In addition to Holocene and modern deposits of San Francisco Bay, an older estuarine unit occurs in the stratigraphic section. The older unit was deposited during a period of high sea level, tentatively correlated with the Sangamon interglacial period. Because evidence of the Blake event is not present in the older estuarine unit, the proposed age of this unit could not be confirmed. Although the Holocene estuarine deposits of South San Francisco Bay carry stable remanent magnetization, a reliable record of geomagnetic secular variation could not be recovered because the water-saturated sdiment was deformed by drilling.

Seagrass community dynamics in a subtropical estuarine lagoon

Energy Technology Data Exchange (ETDEWEB)

Thorhaug, A.; Roessler, M.A.

1977-11-01

The temporal and spatial distributions of major plant and animal species were investigated for 4 years in south Biscayne Bay including Card Sound, Florida, a subtropical estuarine lagoon. This was part of a larger study including chemical, physical and geological investigations. The major species of plants were Thalassia testudinum Banks ex Konig, turtle grass, Laurencia poitei (Lamour.) Howe, a red macroalga and the green algae Penicillus capitatus Lamarck and Halimeda incrassata (Ellis) Lamour. Standing crop and production of plant material taken bi-weekly is given in detail for 16 stations in Card Sound for the 4-year period and for eight stations in Biscayne Bay for a 1-year period. The major animal species were not equally distributed; in the near-shore Thalassia community, species of Pagurus, Neopanope, Hippolyte, Cerithium, Bulla, Prunum and Modulus were dominant. In mid-bay, where patchy Thalassia plus green algae occurred, Thor and Chondrilla were the dominant animals. Near the fringing islands, where tidal flow caused more oceanic conditions, the community was dominated by sponges, urchins and corals. This highlights the structural differences in what is now termed the ''Thalassia community.'' Comparisons with other known Thalassia communities are made.

δ 15N Studies of Nitrogen Use by the Red Mangrove, Rhizophora mangle L. in South Florida

Science.gov (United States)

Fry, B.; Bern, A. L.; Ross, M. S.; Meeder, J. F.

2000-02-01

To help define nitrogen (N) sources and patterns of N processing in mangrove ecosystems, mangrove leaf nitrogen contents and δ 15N values were assayed in three marshes along the south Florida coast. In each marsh, leaf samples were collected from dwarf mangroves at interior locations and taller mangroves at the ocean fringe. Leaf % N and δ 15N values did not differ consistently between dwarf and tall mangroves, even though there were large variations in δ 15N (18‰ range, -5 to +13‰) and % N (1·2% range, 0·9-2·1%). Highest % N and δ 15N values occurred along the western margin of Biscayne Bay where canals draining agricultural lands deliver high-nitrate waters to fringing mangrove marshes. High mangrove δ 15N values may be good biomonitors of anthropogenic N loading to south Florida estuaries. Lower values likely reflect less anthropogenic N entering the mangrove marshes, as well as differences in plant physiology that occur along the fringe-dwarf gradient.

33 CFR 334.770 - Gulf of Mexico and St. Andrew Sound, south of East Bay, Fla., Tyndall Drone Launch Corridor...

Science.gov (United States)

2010-07-01

... Sound, south of East Bay, Fla., Tyndall Drone Launch Corridor, Tyndall Air Force Base, Fla.; restricted.... Andrew Sound, south of East Bay, Fla., Tyndall Drone Launch Corridor, Tyndall Air Force Base, Fla... referred to as the “Tyndall Drone Launch Corridor.” (b) The regulations. (1) Military usage of areas is...

Characterization of the porosity distribution in the upper part of the karst Biscayne aquifer using common offset ground penetrating radar, Everglades National Park, Florida

Science.gov (United States)

Mount, Gregory J.; Comas, Xavier; Cunningham, Kevin J.

2014-07-01

The karst Biscayne aquifer is characterized by a heterogeneous spatial arrangement of porosity and hydraulic conductivity, making conceptualization difficult. The Biscayne aquifer is the primary source of drinking water for millions of people in south Florida; thus, information concerning the distribution of karst features that concentrate the groundwater flow and affect contaminant transport is critical. The principal purpose of the study was to investigate the ability of two-dimensional ground penetrating radar (GPR) to rapidly characterize porosity variability in the karst Biscayne aquifer in south Florida. An 800-m-long GPR transect of a previously investigated area at the Long Pine Key Nature Trail in Everglades National Park, collected in fast acquisition common offset mode, shows hundreds of diffraction hyperbolae. The distribution of diffraction hyperbolae was used to estimate electromagnetic (EM) wave velocity at each diffraction location and to assess both horizontal and vertical changes in velocity within the transect. A petrophysical model (complex refractive index model or CRIM) was used to estimate total bulk porosity. A set of common midpoint surveys at selected locations distributed along the common-offset transect also were collected for comparison with the common offsets and were used to constrain one-dimensional (1-D) distributions of porosity with depth. Porosity values for the saturated Miami Limestone ranged between 25% and 41% for common offset GPR surveys, and between 23% and 39% for common midpoint GPR surveys. Laboratory measurements of porosity in five whole-core samples from the saturated part of the aquifer in the study area ranged between 7.1% and 41.8%. GPR estimates of porosity were found to be valid only under saturated conditions; other limitations are related to the vertical resolution of the GPR signal and the volume of the material considered by the measurement methodology. Overall, good correspondence between GPR estimates and

Mapping saltwater intrusion in the Biscayne Aquifer, Miami-Dade County, Florida using transient electromagnetic sounding

Science.gov (United States)

Fitterman, David V.

2014-01-01

Saltwater intrusion in southern Florida poses a potential threat to the public drinking-water supply that is typically monitored using water samples and electromagnetic induction logs collected from a network of wells. Transient electromagnetic (TEM) soundings are a complementary addition to the monitoring program because of their ease of use, low cost, and ability to fill in data gaps between wells. TEM soundings have been used to map saltwater intrusion in the Biscayne aquifer over a large part of south Florida including eastern Miami-Dade County and the Everglades. These two areas are very different with one being urban and the other undeveloped. Each poses different conditions that affect data collection and data quality. In the developed areas, finding sites large enough to make soundings is difficult. The presence of underground pipes further restricts useable locations. Electromagnetic noise, which reduces data quality, is also an issue. In the Everglades, access to field sites is difficult and working in water-covered terrain is challenging. Nonetheless, TEM soundings are an effective tool for mapping saltwater intrusion. Direct estimates of water quality can be obtained from the inverted TEM data using a formation factor determined for the Biscayne aquifer. This formation factor is remarkably constant over Miami-Dade County owing to the uniformity of the aquifer and the absence of clay. Thirty-six TEM soundings were collected in the Model Land area of southeast Miami-Dade County to aid in calibration of a helicopter electromagnetic (HEM) survey. The soundings and HEM survey revealed an area of saltwater intrusion aligned with canals and drainage ditches along U.S. Highway 1 and the Card Sound Road. These canals and ditches likely reduced freshwater levels through unregulated drainage and provided pathways for seawater to flow at least 12.4 km inland.

Inhomogeneity of optical turbulence over False Bay (South Africa)

Science.gov (United States)

Ullwer, Carmen; Sprung, Detlev; van Eijk, Alexander M. J.; Gunter, Willi; Stein, Karin

2017-09-01

Atmospheric turbulence impacts on the propagation of electro-optical radiation. Typical manifestations of optical turbulence are scintillation (intensity fluctuations), beam wander and (for laser systems) reduction of beam quality. For longer propagation channels, it is important to characterize the vertical and horizontal distribution (inhomogeneity) of the optical turbulence. In the framework of the First European South African Transmission ExpeRiment (FESTER) optical turbulence was measured between June 2015 and February 2016 on a 2 km over-water link over False Bay. The link ran from the Institute of Maritime Technology (IMT) in Simons Town to the lighthouse at Roman Rock Island. Three Boundary layer scintillometers (BLS900) allowed assessing the vertical distribution of optical turbulence at three different heights between 5 and 12 m above the water surface. The expected decrease of Cn2 with height is not always found. These results are analyzed in terms of the meteorological scenarios, and a comparison is made with a fourth optical link providing optical turbulence data over a 8.7 km path from IMT to Kalk Bay, roughly 36° to the north of the three 2 km paths. The results are related to the inhomogeneous meteorological conditions over the Bay as assessed with the numerical weather prediction tool, the Weather Forecast and Research model WRF.

75 FR 21650 - Coral Reef Restoration Plan, Draft Programmatic Environmental Impact Statement, Biscayne National...

Science.gov (United States)

2010-04-26

... DEPARTMENT OF THE INTERIOR National Park Service Coral Reef Restoration Plan, Draft Programmatic... Coral Reef Restoration Plan, Biscayne National Park. SUMMARY: Pursuant to the National Environmental... availability of a Draft Programmatic Environmental Impact Statement (DEIS) for the Coral Reef Restoration Plan...

First results on the Experiment FESTER on optical turbulence over False Bay South Africa: Dependencies and consequences

NARCIS (Netherlands)

Sprung, D.; Van Eijk, A.M.J.; Sucher, E.; Eisele, C.; Seiffer, D.; Stein, K.

2016-01-01

The experiment FESTER (First European South African Transmission ExpeRiment) took place in 2015 to investigate the atmospheric influence on electro-optical systems performance across False Bay / South Africa on a long term basis. Several permanent stations for monitoring electro-optical propagation

77 FR 62437 - Regulated Navigation Area; Columbus Day Weekend, Biscayne Bay, Miami, FL

Science.gov (United States)

2012-10-15

... Acronyms DHS Department of Homeland Security FR Federal Register NPRM Notice of Proposed Rulemaking RNA Regulated Navigation Area I. Regulatory History and Information On July 25, 2012, we published a Notice of... Bay Columbus Day regulated navigation area (RNA), established in 2011 and contained in 33 CFR 165.779...

Application of a Density-Dependent Numerical Model (MODHMS) to Assess Salinity Intrusion in the Biscayne Aquifer, North Miami-Dade County, Florida

Science.gov (United States)

Guha, H.; Panday, S.

2005-05-01

. Saltwater intrusion in the Biscayne aquifer is the result of a combination of natural variations in recharge, evapotranspiration, ground-water withdrawals from the aquifer, and relative canal stages in comparison to tidal stages in the Biscayne Bay. Pre- and post wellfield pumpage scenarios were conducted to determine the effect of wellfield pumpage on saltwater intrusion. The model is being used for future water supply management scenarios and for evaluating the best placement of saltwater intrusion monitoring wells along the coast.

76 FR 24050 - Coral Reef Restoration Plan, Final Programmatic Environmental Impact Statement, Biscayne National...

Science.gov (United States)

2011-04-29

... DEPARTMENT OF THE INTERIOR National Park Service [2310-0003-422] Coral Reef Restoration Plan... for the Coral Reef Restoration Plan, Biscayne National Park. SUMMARY: Pursuant to the National... availability of a Final Programmatic Environmental Impact Statement for the Coral Reef Restoration Plan (Plan...

Ecological evaluation of proposed dredged material from Winyah Bay, South Carolina

International Nuclear Information System (INIS)

Ward, J.A.; Gardiner, W.W.; Pinza, M.R.; Word, J.Q.

1993-10-01

The navigational channels of Winyah Bay, Georgetown Harbor, South Carolina require dredging to enable normal shipping traffic to use these areas. Before dredging, environmental assessments must be conducted to determine the suitability of this dredged sediment for unconfined, open-water disposal. The Charleston, South Carolina District Office of the US Army Corps of Engineers (USACE) requested that the Battelle/Marine Science Laboratory (MSL) collect sediment samples and conduct the required physical/chemical, toxicological, and bioaccumulation evaluations as required in the 1991 Implementation Manual. This report is intended to provide information required to address potential ecological effects of the Entrance Channel and Inner Harbor sediments proposed disposal in the ocean

Electrical resistivity characterization of anisotropy in the Biscayne Aquifer.

Science.gov (United States)

Yeboah-Forson, Albert; Whitman, Dean

2014-01-01

Electrical anisotropy occurs when electric current flow varies with azimuth. In porous media, this may correspond to anisotropy in the hydraulic conductivity resulting from sedimentary fabric, fractures, or dissolution. In this study, a 28-electrode resistivity imaging system was used to investigate electrical anisotropy at 13 sites in the Biscayne Aquifer of SE Florida using the rotated square array method. The measured coefficient of electrical anisotropy generally ranged from 1.01 to 1.12 with values as high as 1.36 found at one site. The observed electrical anisotropy was used to estimate hydraulic anisotropy (ratio of maximum to minimum hydraulic conductivity) which ranged from 1.18 to 2.83. The largest values generally were located on the Atlantic Coastal Ridge while the lowest values were in low elevation areas on the margin of the Everglades to the west. The higher values of anisotropy found on the ridge may be due to increased dissolution rates of the oolitic facies of the Miami formation limestone compared with the bryozoan facies to the west. The predominate trend of minimum resistivity and maximum hydraulic conductivity was E-W/SE-NW beneath the ridge and E-W/SW-NE farther west. The anisotropy directions are similar to the predevelopment groundwater flow direction as indicated in published studies. This suggests that the observed anisotropy is related to the paleo-groundwater flow in the Biscayne Aquifer. © 2013, National Ground Water Association.

An experimental study of radiative fluxes in the south Bay of Bengal

Indian Academy of Sciences (India)

Time series measurements of radiative fluxes were made onboard INS Sagardhwani (SD) in the south Bay of Bengal near DS3 (13°N and 87°E) during the BOBMEX field experiment. An inter- comparison experiment conducted at DS3 showed that the radiative fluxes measured by Kipp and Zonen, Albedo meter and net ...

Estimates of bottom roughness length and bottom shear stress in South San Francisco Bay, California

Science.gov (United States)

Cheng, R.T.; Ling, C.-H.; Gartner, J.W.; Wang, P.-F.

1999-01-01

A field investigation of the hydrodynamics and the resuspension and transport of participate matter in a bottom boundary layer was carried out in South San Francisco Bay (South Bay), California, during March-April 1995. Using broadband acoustic Doppler current profilers, detailed measurements of turbulent mean velocity distribution within 1.5 m above bed have been obtained. A global method of data analysis was used for estimating bottom roughness length zo and bottom shear stress (or friction velocities u*). Field data have been examined by dividing the time series of velocity profiles into 24-hour periods and independently analyzing the velocity profile time series by flooding and ebbing periods. The global method of solution gives consistent properties of bottom roughness length zo and bottom shear stress values (or friction velocities u*) in South Bay. Estimated mean values of zo and u* for flooding and ebbing cycles are different. The differences in mean zo and u* are shown to be caused by tidal current flood-ebb inequality, rather than the flooding or ebbing of tidal currents. The bed shear stress correlates well with a reference velocity; the slope of the correlation defines a drag coefficient. Forty-three days of field data in South Bay show two regimes of zo (and drag coefficient) as a function of a reference velocity. When the mean velocity is >25-30 cm s-1, the ln zo (and thus the drag coefficient) is inversely proportional to the reference velocity. The cause for the reduction of roughness length is hypothesized as sediment erosion due to intensifying tidal currents thereby reducing bed roughness. When the mean velocity is <25-30 cm s-1, the correlation between zo and the reference velocity is less clear. A plausible explanation of scattered values of zo under this condition may be sediment deposition. Measured sediment data were inadequate to support this hypothesis, but the proposed hypothesis warrants further field investigation.

33 CFR 334.720 - Gulf of Mexico, south from Choctawhatchee Bay; guided missiles test operations area, Headquarters...

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Gulf of Mexico, south from..., DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.720 Gulf of Mexico, south from Choctawhatchee Bay; guided missiles test operations area, Headquarters Air Proving...

Integration of electrical resistivity imaging and ground penetrating radar to investigate solution features in the Biscayne Aquifer

Science.gov (United States)

Yeboah-Forson, Albert; Comas, Xavier; Whitman, Dean

2014-07-01

The limestone composing the Biscayne Aquifer in southeast Florida is characterized by cavities and solution features that are difficult to detect and quantify accurately because of their heterogeneous spatial distribution. Such heterogeneities have been shown by previous studies to exert a strong influence in the direction of groundwater flow. In this study we use an integrated array of geophysical methods to detect the lateral extent and distribution of solution features as indicative of anisotropy in the Biscayne Aquifer. Geophysical methods included azimuthal resistivity measurements, electrical resistivity imaging (ERI) and ground penetrating radar (GPR) and were constrained with direct borehole information from nearby wells. The geophysical measurements suggest the presence of a zone of low electrical resistivity (from ERI) and low electromagnetic wave velocity (from GPR) below the water table at depths of 4-9 m that corresponds to the depth of solution conduits seen in digital borehole images. Azimuthal electrical measurements at the site reported coefficients of electrical anisotropy as high as 1.36 suggesting the presence of an area of high porosity (most likely comprising different types of porosity) oriented in the E-W direction. This study shows how integrated geophysical methods can help detect the presence of areas of enhanced porosity which may influence the direction of groundwater flow in a complex anisotropic and heterogeneous karst system like the Biscayne Aquifer.

Metals and pesticides in commercial bivalve mollusc production areas in the North and South Bays, Santa Catarina (Brazil).

Science.gov (United States)

de Souza, R V; Garbossa, L H P; Campos, C J A; Vianna, L F de N; Vanz, A; Rupp, G S

2016-04-15

Concentrations of heavy metals were quantified in mussels Perna perna and Pacific oysters Crassostrea gigas in 28 cultivation sites in the North and South Bays, SC (Brazil). Concentrations of pesticides were also quantified in these bivalve, water and sediment samples collected in 14 cultivation sites on four occasions in the period October 2012-October 2013. Pesticides were not detected in any of the mussel, oyster, water or sediment samples. The South Bay was found to be generally more contaminated with As while the North Bay showed higher concentrations of Ni. Concentrations of Pb and Cd were below the limit of detection of the method (0.5mg/kg) in all samples. Mussels accumulated more As and Ni than oysters, while the opposite was observed for Cu. Metal concentrations were below the maximum levels for foodstuffs specified in the Brazilian legislation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Comparison of test specific sediment effect concentrations with marine sediment quality assessment guidelines

International Nuclear Information System (INIS)

Carr, R.S.; Biedenbach, J.M.; MacDonald, D.D.

1995-01-01

As part of NOAA's National Status and Trends (NS and T) Bioeffects Assessment program and studies conducted by the National Biological Service, numerous sediment quality assessment surveys have recently been conducted along the Atlantic and Gulf coasts of the US using the sea urchin (Arbacia punctulata) fertilization and embryological development tests with pore water. Additional toxicity tests were also conducted in conjunction with most of these studies. The areas that have been sampled include Boston harbor, Massachusetts; Charleston Harbor, Winyah Bay, and Savannah River, South Carolina; St. Simon Sound, Georgia; Biscayne Bay, Tampa Bay, Choctawhatchee Bay, Apalachicola Bay, St. Andrew Bay, and Pensacola Bay, Florida; Galveston Bay, Lavaca Bay, and Sabine Lake, Texas, and 200 stations in the vicinity of offshore oil and gas production platforms in the Gulf of Mexico. Sufficient data are now available from this series of surveys to calculate test specific sediment effect concentrations (SECs). Based on these recent studies, SECs were developed for the sea urchin porewater and amphipod tests and compared with existing marine sediment quality assessment guidelines

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...

Foraminiferal record of Holocene paleo-earthquakes on the subsiding south-western Poverty Bay coastline, New Zealand

International Nuclear Information System (INIS)

Hayward, B.W.; Sabaa, A.T.; Grenfell, H.R.; Cochran, U.A.; Clark, K.J.; Litchfield, N.J.; Wallace, L.M.; Marden, M.; Palmer, A.S.

2015-01-01

Foraminiferal faunas in 29 short cores (maximum depth 7 m) of estuarine and coastal wetland sediment were used to reconstruct the middle-late Holocene (last 7 ka) elevational history on the southern shores of Poverty Bay, North Island, New Zealand. This coast is on the southwest side of a rapidly subsiding area beneath western Poverty Bay. Modern Analogue Technique paleo-elevation estimates based on fossil foraminiferal faunas indicate that the four study areas have gradual late Holocene (<3.5 ka) subsidence rates that increase from the southwest (mean c. 0.5 m ka - - 1 ) to northeast (mean c. 1.0 m ka -1 ). Only two rapid, possibly co-seismic, vertical displacement events are recognised: (1) c. 1.2 m of subsidence at 5.7 ± 0.4 ka (cal yr BP), which may have been generated by a subduction interface earthquake centred offshore and recorded in other published studies in northern Hawkes Bay, c. 35 km to the south; and (2) c. 1 m of uplift (relative sea-level fall) at c. 4.5 ± 0.3 ka, which might have been generated by rupture on an offshore upper plate fault that also uplifted coastal terraces at Pakarae and Mahia, 40 km to the north and south of the study area, or by rupture on the subduction interface penetrating beneath Poverty Bay. No sudden displacement events are recognised during the last 4 ka although subsidence, possibly aseismic, has continued. (author).

Coral bleaching on high-latitude marginal reefs at Sodwana Bay, South Africa

International Nuclear Information System (INIS)

Celliers, Louis; Schleyer, Michael H.

2002-01-01

Coral bleaching, involving the expulsion of symbiotic zooxanthellae from the host cells, poses a major threat to coral reefs throughout their distributional range. The role of temperature in coral bleaching has been extensively investigated and is widely accepted. A bleaching event was observed on the marginal high-latitude reefs of South Africa located at Sodwana Bay during the summer months of 2000. This was associated with increased sea temperatures with high seasonal peaks in summer and increased radiation in exceptionally clear water. The bleaching was limited to Two-mile Reef and Nine-mile Reef at Sodwana Bay and affected -1 from May 1994 to April 2000. High maximum temperatures were measured (>29 deg. C). The lowest mean monthly and the mean maximum monthly temperatures at which coral bleaching occurred were 27.5 and 28.8 deg. C, respectively, while the duration for which high temperatures occurred in 2000 was 67 days at ≥27.5 deg. C (4 days at ≥28.8 deg. C). Increased water clarity and radiation appeared to be a synergistic cause in the coral bleaching encountered at Sodwana Bay

Waterbird egg mercury concentrations in response to wetland restoration in south San Francisco Bay, California

Science.gov (United States)

Ackerman, Joshua T.; Herzog, Mark P.; Hartman, Christopher A.; Watts, Trevor C.; Barr, Jarred R.

2014-01-01

The conversion of 50–90 percent of 15,100 acres of former salt evaporation ponds to tidal marsh habitat in the south San Francisco Bay, California, is planned as part of the South Bay Salt Pond Restoration Project. This large-scale habitat restoration may change the bioavailability of methylmercury. The South Bay already is known to have high methylmercury concentrations, with methylmercury concentrations in several waterbirds species more than known toxicity thresholds where avian reproduction is impaired. In this 2013 study, we continued monitoring bird egg mercury concentrations in response to the restoration of the Pond A8/A7/A5 Complex to a potential tidal marsh in the future. The restoration of the Pond A8/A7/A5 Complex began in autumn 2010, and the Pond A8 Notch was opened 5 feet (one of eight gates) to muted tidal action on June 1, 2011, and then closed in the winter. In autumn 2010, internal levees between Ponds A8, A7, and A5 were breached and water depths were substantially increased by flooding the Pond A8/A7/A5 Complex in February 2011. In June 2012, 15 feet (three of eight gates) of the Pond A8 Notch was opened, and then closed in December 2012. In June 2013, 15 feet of the Pond A8 Notch again was opened, and the Pond A8/A7/A5 Complex was a relatively deep and large pond with muted tidal action in the summer. This report synthesizes waterbird data from the 2013 breeding season, and combines it with our prior study’s data from 2010 and 2011.

Results of time-domain electromagnetic soundings in Everglades National Park, Florida

Science.gov (United States)

Fitterman, D.V.; Deszcz-Pan, Maria; Stoddard, C.E.

1999-01-01

This report describes the collection, processing, and interpretation of time-domain electromagnetic soundings from Everglades National Park. The results are used to locate the extent of seawater intrusion in the Biscayne aquifer and to map the base of the Biscayne aquifer in regions where well coverage is sparse. The data show no evidence of fresh, ground-water flows at depth into Florida Bay.

Phase 1 studies summary of major findings of the South Bay Salt Pond Restoration Project, South San Francisco Bay, California

Science.gov (United States)

Valoppi, Laura

2018-04-02

Executive SummaryThe South Bay Salt Pond Restoration Project (Project) is one of the largest restoration efforts in the United States. It is located in South San Francisco Bay of California. It is unique not only for its size—more than 15,000 acres—but also for its location adjacent to one of the nation’s largest urban areas, home to more than 4 million people (Alameda, Santa Clara, and San Mateo Counties). The Project is intended to restore and enhance wetlands in South San Francisco Bay while providing for flood management, wildlife-oriented public access, and recreation. Restoration goals of the project are to provide a mosaic of saltmarsh habitat to benefit marsh species and managed ponds to benefit waterbirds, throughout 3 complexes and 54 former salt ponds.Although much is known about the project area, significant uncertainties remain with a project of this geographic and temporal scale of an estimated 50 years to complete the restoration. For example, in order to convert anywhere from 50 to 90 percent of the existing managed ponds to saltmarsh habitat, conservation managers first enhance the habitat of managed ponds in order to increase use by waterbirds, and provide migratory, wintering, and nesting habitat for more than 90 species of waterbirds. Project managers have concluded that the best way to address these uncertainties is to carefully implement the project in phases and learn from the outcome of each phase. The Adaptive Management Plan (AMP) identifies specific restoration targets for multiple aspects of the Project and defines triggers that would necessitate some type of management action if a particular aspect is trending negatively. U.S. Geological Survey (USGS) biologist Laura Valoppi served as the project Lead Scientist and oversaw implementation of the AMP in coordination with other members of the Project Management Team (PMT), comprised of representatives from the California State Coastal Conservancy, California Department of Fish and

Prominence of ichnologically influenced macroporosity in the karst Biscayne aquifer: Stratiform "super-K" zones

Science.gov (United States)

Cunningham, K.J.; Sukop, M.C.; Huang, H.; Alvarez, P.F.; Curran, H.A.; Renken, R.A.; Dixon, J.F.

2009-01-01

A combination of cyclostratigraphic, ichnologic, and borehole geophysical analyses of continuous core holes; tracer-test analyses; and lattice Boltzmann flow simulations was used to quantify biogenic macroporosity and permeability of the Biscayne aquifer, southeastern Florida. Biogenic macroporosity largely manifests as: (1) ichnogenic macroporosity primarily related to postdepositional burrowing activity by callianassid shrimp and fossilization of components of their complex burrow systems (Ophiomorpha); and (2) biomoldic macroporosity originating from dissolution of fossil hard parts, principally mollusk shells. Ophiomorpha-dominated ichno-fabric provides the greatest contribution to hydrologic characteristics in the Biscayne aquifer in a 345 km2 study area. Stratiform tabular-shaped units of thalassinidean-associated macroporosity are commonly confined to the lower part of upward-shallowing high-frequency cycles, throughout aggradational cycles, and, in one case, they stack vertically within the lower part of a high-frequency cycle set. Broad continuity of many of the macroporous units concentrates groundwater flow in extremely permeable passage-ways, thus making the aquifer vulnerable to long-distance transport of contaminants. Ichnogenic macroporosity represents an alternative pathway for concentrated groundwater flow that differs considerably from standard karst flow-system paradigms, which describe groundwater movement through fractures and cavernous dissolution features. Permeabilities were calculated using lattice Boltzmann methods (LBMs) applied to computer renderings assembled from X-ray computed tomography scans of various biogenic macroporous limestone samples. The highest simulated LBM permeabilities were about five orders of magnitude greater than standard laboratory measurements using air-permeability methods, which are limited in their application to extremely permeable macroporous rock samples. Based on their close conformance to analytical

33 CFR 334.220 - Chesapeake Bay, south of Tangier Island, Va.; naval firing range.

Science.gov (United States)

2010-07-01

... ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.220 Chesapeake Bay, south of Tangier Island, Va.; naval firing range. (a) The danger zone. Beginning... to latitude 37°45′00″, longitude 76°09′48″; thence to latitude 37°45′00″, longitude 76°08′51″; and...

Human and riverine impacts on the dynamics of seawater nutrient and carbon parameters in Kwangyang Bay, South Korea

Science.gov (United States)

Kim, Tae-Wook; Kim, Dongseon; Baek, Seung Ho; Kim, Young Ok

2015-04-01

We investigated seawater nutrient and carbon parameters in Kwangyang Bay, South Korea, which has been exposed to significant human influences, in each core month of four seasons for between 2010 and 2012. The survey data were analyzed using multivariate statistics analysis (cluster and factor analysis). As a result, we found that the Seomjin River (the fifth largest river in South Korea) and biological activity, including phytoplankton photosynthesis and bacterial decomposition, were the main factors determining the overall water quality of the bay. However, the impacts of these factors varied both spatially and seasonally, because the factors were linked with the geographical environments and seasonal variations in freshwater discharge. In particular, the Seomjin River was primarily responsible for nitrate, silicate, total alkalinity, and dissolved inorganic carbon, and exhibited a significant impact in the summer. During the past 10 years, nutrient loads from the river and industrial complexes to the bay have decreased. The impacts of this decrease are visible in the phosphate concentration, which has fallen to a third of its initial value. We also examined the potential role of atmospheric nitrogen deposition in nitrogen cycling in the study area.

New species of the genus Sinularia (Octocorallia: Alcyonacea) from Nha Trang Bay, South China Sea, Vietnam

NARCIS (Netherlands)

Dautova, T.N.; Ofwegen, van L.P.; Savinkin, O.V.

2010-01-01

A total of eight Sinularia species is described and depicted, all from Nha Trang Bay, Vietnam (South China Sea). Six are new to science: S. capricornis, S. multiflora, S. pumila, S. sarmentosa, S. torta, and S. uva. Two other ones represent just new records for Vietnam: S. rigida (Dana, 1846) and S.

A numerical model investigation of the impacts of Hurricane Sandy on water level variability in Great South Bay, New York

Science.gov (United States)

Bennett, Vanessa C. C.; Mulligan, Ryan P.; Hapke, Cheryl J.

2018-06-01

Hurricane Sandy was a large and intense storm with high winds that caused total water levels from combined tides and storm surge to reach 4.0 m in the Atlantic Ocean and 2.5 m in Great South Bay (GSB), a back-barrier bay between Fire Island and Long Island, New York. In this study the impact of the hurricane winds and waves are examined in order to understand the flow of ocean water into the back-barrier bay and water level variations within the bay. To accomplish this goal, a high resolution hurricane wind field is used to drive the coupled Delft3D-SWAN hydrodynamic and wave models over a series of grids with the finest resolution in GSB. The processes that control water levels in the back-barrier bay are investigated by comparing the results of four cases that include: (i) tides only; (ii) tides, winds and waves with no overwash over Fire Island allowed; (iii) tides, winds, waves and limited overwash at the east end of the island; (iv) tides, winds, waves and extensive overwash along the island. The results indicate that strong local wind-driven storm surge along the bay axis had the largest influence on the total water level fluctuations during the hurricane. However, the simulations allowing for overwash have higher correlation with water level observations in GSB and suggest that island overwash provided a significant contribution of ocean water to eastern GSB during the storm. The computations indicate that overwash of 7500-10,000 m3s-1 was approximately the same as the inflow from the ocean through the major existing inlet. Overall, the model results indicate the complex variability in total water levels driven by tides, ocean storm surge, surge from local winds, and overwash that had a significant impact on the circulation in Great South Bay during Hurricane Sandy.

Characterization of aquifer heterogeneity using Cyclostratigraphy and geophysical methods in the upper part of the Karstic Biscayne Aquifer, Southeastern Florida

Science.gov (United States)

Cunningham, Kevin J.; Carlson, Janine L.; Wingard, G. Lynn; Robinson, Edward; Wacker, Michael A.

2004-01-01

This report identifies and characterizes candidate ground-water flow zones in the upper part of the shallow, eogenetic karst limestone of the Biscayne aquifer in the Lake Belt area of north-central Miami-Dade County using cyclostratigraphy, ground-penetrating radar (GPR), borehole geophysical logs, and continuously drilled cores. About 60 miles of GPR profiles were used to calculate depths to shallow geologic contacts and hydrogeologic units, image karst features, and produce qualitative views of the porosity distribution. Descriptions of the lithology, rock fabrics, and cyclostratigraphy, and interpretation of depositional environments of 50 test coreholes were linked to the geophysical interpretations to provide an accurate hydrogeologic framework. Molluscan and benthic foraminiferal paleontologic constraints guided interpretation of depositional environments represented by rockfabric facies. Digital borehole images were used to characterize and quantify large-scale vuggy porosity. Preliminary heat-pulse flowmeter data were coupled with the digital borehole image data to identify candidate ground-water flow zones. Combined results show that the porosity and permeability of the karst limestone of the Biscayne aquifer have a highly heterogeneous and anisotropic distribution that is mostly related to secondary porosity overprinting vertical stacking of rock-fabric facies within high-frequency cycles (HFCs). This distribution of porosity produces a dual-porosity system consisting of diffuse-carbonate and conduit flow zones. The nonuniform ground-water flow in the upper part of the Biscayne aquifer is mostly localized through secondary permeability, the result of solution-enlarged carbonate grains, depositional textures, bedding planes, cracks, root molds, and paleokarst surfaces. Many of the resulting pore types are classified as touching vugs. GPR, borehole geophysical logs, and whole-core analyses show that there is an empirical relation between formation porosity

Bathymetry and digital elevation models of Coyote Creek and Alviso Slough, South San Francisco Bay, California

Science.gov (United States)

Foxgrover, Amy C.; Finlayson, David P.; Jaffe, Bruce E.; Fregoso, Theresa A.

2012-01-05

In 2010 the U.S. Geological Survey (USGS), Pacific Coastal and Marine Science Center completed three cruises to map the bathymetry of the main channel and shallow intertidal mudflats in the southernmost part of south San Francisco Bay. The three surveys were merged to generate comprehensive maps of Coyote Creek (from Calaveras Point east to the railroad bridge) and Alviso Slough (from the bay to the town of Alviso) to establish baseline bathymetry prior to the breaching of levees adjacent to Alviso and Guadalupe Sloughs as part of the South Bay Salt Pond Restoration Project (http://www.southbayrestoration.org). Since 2010 the USGS has conducted twelve additional surveys to monitor bathymetric change in this region as restoration progresses.The bathymetry surveys were conducted using the state-of-the-art research vessel R/V Parke Snavely outfitted with an interferometric sidescan sonar for swath mapping in extremely shallow water. This publication provides high-resolution bathymetric data collected by the USGS. For the 2010 baseline survey we have merged the bathymetry with aerial lidar data that were collected for the USGS during the same time period to create a seamless, high-resolution digital elevation model (DEM) of the study area. The series of bathymetry datasets are provided at 1 m resolution and the 2010 bathymetric/topographic DEM at 2 m resolution. The data are formatted as both X, Y, Z text files and ESRI Arc ASCII files that are accompanied by Federal Geographic Data Committee (FGDC) compliant metadata.

Distribution of radionuclides in a marine sediment core off the waterspout of the nuclear power plants in Daya Bay, northeastern South China Sea

International Nuclear Information System (INIS)

Zhou, Peng; Li, Dongmei; Li, Haitao; Fang, Hongda; Huang, Chuguang; Zhang, Yusheng; Zhang, Hongbiao; Zhao, Li; Zhou, Junjie; Wang, Hua; Yang, Jie

2015-01-01

A sediment core was collected and dated using 210 Pb ex dating method off the waterspout of nuclear power base of Daya Bay, northeastern South China Sea. The γ-emitting radionuclides were analyzed using HPGe γ spectrometry, gross alpha and beta radioactivity as well as other geochemical indicators were deliberated to assess the impact of nuclear power plants (NPP) operation and to study the past environment changes. It suggested that NPP provided no new radioactivity source to sediment based on the low specific activity of 137 Cs. Two broad peaks of TOC, TC and LOI accorded well with the commercial operations of Daya Bay NPP (1994.2 and 1994.5) and LNPP Phase I (2002.5 and 2003.3), implying that the mass input of cooling water from NPP may result into a substantial change in the ecological environment and Daya Bay has been severely impacted by human activities. - Graphical abstract: A sediment core was collected and dated using 210 Pb ex dating method, off the waterspout of nuclear power base of Daya Bay, northeastern South China Sea. The γ-emitting radionuclides analyzed using the HPGe γ spectrometry, gross alpha and beta radioactivity as well as other geochemical indicators were deliberated to study the past environment changes and assess the impact of nuclear power plants (NPP) operation. NPP provided no new radioactivity source to sediment, but the mass input of cooling water from nuclear power plants may result into a substantial change in the ecological environment and Daya Bay has been severely impacted by human activities. - Highlights: • A sediment core collected from Daya Bay, South China Sea was dated using 210 Pb ex method. • The γ-emitting radionuclides, gross α and β, TOC, TIC, TC, LOI were deliberated to assess the impact of nuclear power plants (NPP) operation. • The low activity of 137 Cs in sediment suggested NPP provided no new radioactivity source. • Two peaks of TOC, TC and LOI implied that the mass input of NPP cooling water may

Is metal pollution a threat to the continued survival of the starfish in False Bay, South Africa?

Directory of Open Access Journals (Sweden)

Adriaan J. Reinecke

2013-02-01

Full Text Available Urbanisation and industrial development in the catchment area of False Bay in South Africa are increasing and concern was raised about the effect of environmental pollutants on intertidal fauna such as starfish. The aim of the present study was to obtain initial descriptive baseline data over several seasons during 2000–2001 of metal concentrations in water, sediment and body samples of the chosen cushion starfish Parvulastra exigua (Lamarck, 1816 that occurs widely in the intertidal zone of False Bay. Concentrations of cadmium, copper, lead, nickel and zinc were measured in samples of the cushion starfish, water and sediment at five localities along the coast of False Bay. The samples were chemically analysed for metals by atomic spectrophotometry. The highest individually measured concentrations of cadmium (Cd in starfish and sediment were found in the northern coastal region between Strand and Muizenberg where most industrial activity and human settlement occur. Large variation in concentrations of all metals occurred between localities and seasons. The mean concentrations of Cd and Pb in water and sediment were in a few instances slightly higher than the recommended levels or target values of the South African marine water and sediment quality norms but still lower than those in various developed countries. Indications are that the bay was at the time of this study still less contaminated by metals in comparison with the coastal waters of various other countries. The accumulation of nonessential metals such as cadmium and lead in both sediment and bodies of starfish was nevertheless such that it can be assumed that environmental concentrations in some parts of the bay could over time build up to levels that are detrimental to the species as well as their predators. This study provided evidence that the cushion starfish in False Bay is exposed to several metals of which some are potentially hazardous since they tend to gradually accumulate

Unique thermal record in False Bay

CSIR Research Space (South Africa)

Grundlingh, ML

1993-10-01

Full Text Available Over the past decade False Bay has assumed a prime position in terms of research in to large South African bays. This is manifested by investigations that cover flow conditions modelling, thermal structure, management, biology and nutrients, geology...

Evaluation of social attraction measures to establish Forster’s tern (Sterna forsteri) nesting colonies for the South Bay Salt Pond Restoration Project, San Francisco Bay, California—2017 Annual Report

Science.gov (United States)

Hartman, C. Alex; Ackerman, Joshua T.; Herzog, Mark P.; Wang, Yiwei; Strong, Cheryl

2018-05-31

Forster’s terns (Sterna forsteri), historically one of the most numerous colonial-breeding waterbirds in South San Francisco Bay, California, have had recent decreases in the number of nesting colonies and overall breeding population size. The South Bay Salt Pond (SBSP) Restoration Project aims to restore 50–90 percent of former salt evaporation ponds to tidal marsh habitat in South San Francisco Bay. This restoration will remove much of the historical island nesting habitat used by Forster’s terns, American avocets (Recurvirostra americana), and other waterbirds. To address this issue, the SBSP Restoration Project organized the construction of new nesting islands in managed ponds that will not be restored to tidal marsh, thereby providing enduring island nesting habitat for waterbirds. In 2012, 16 new islands were constructed in Pond A16 in the Alviso complex of the Don Edwards San Francisco Bay National Wildlife Refuge, increasing the number of islands in this pond from 4 to 20. However, despite a history of nesting on the four historical islands in Pond A16 before 2012, no Forster’s terns have nested in Pond A16 since the new islands were constructed.In 2017, we used social attraction measures (decoys and electronic call systems) to attract Forster’s terns to islands within Pond A16 to re-establish nesting colonies. We maintained these systems from March through August 2017. To evaluate the effect of these social attraction measures, we also completed waterbird surveys between April and August, where we recorded the number and location of all Forster’s terns and other waterbirds using Pond A16, and monitored waterbird nests. We compared bird survey and nest monitoring data collected in 2017 to data collected in 2015 and 2016, prior to the implementation of social attraction measures, allowing for direct evaluation of social attraction efforts on Forster’s terns.To increase the visibility and stakeholder involvement of this project, we engaged in

A numerical model investigation of the impacts of Hurricane Sandy on water level variability in Great South Bay, New York

Science.gov (United States)

Bennett, Vanessa C. C.; Mulligan, Ryan P.; Hapke, Cheryl J.

2018-01-01

Hurricane Sandy was a large and intense storm with high winds that caused total water levels from combined tides and storm surge to reach 4.0 m in the Atlantic Ocean and 2.5 m in Great South Bay (GSB), a back-barrier bay between Fire Island and Long Island, New York. In this study the impact of the hurricane winds and waves are examined in order to understand the flow of ocean water into the back-barrier bay and water level variations within the bay. To accomplish this goal, a high resolution hurricane wind field is used to drive the coupled Delft3D-SWAN hydrodynamic and wave models over a series of grids with the finest resolution in GSB. The processes that control water levels in the back-barrier bay are investigated by comparing the results of four cases that include: (i) tides only; (ii) tides, winds and waves with no overwash over Fire Island allowed; (iii) tides, winds, waves and limited overwash at the east end of the island; (iv) tides, winds, waves and extensive overwash along the island. The results indicate that strong local wind-driven storm surge along the bay axis had the largest influence on the total water level fluctuations during the hurricane. However, the simulations allowing for overwash have higher correlation with water level observations in GSB and suggest that island overwash provided a significant contribution of ocean water to eastern GSB during the storm. The computations indicate that overwash of 7500–10,000 m3s−1 was approximately the same as the inflow from the ocean through the major existing inlet. Overall, the model results indicate the complex variability in total water levels driven by tides, ocean storm surge, surge from local winds, and overwash that had a significant impact on the circulation in Great South Bay during Hurricane Sandy.

Waterbird nest monitoring program in San Francisco Bay (2005-10)

Science.gov (United States)

Ackerman, Joshua T.; Herzog, Mark P.

2012-01-01

Historically, Forster’s Terns (Sterna forsteri), American Avocets (Recurvirostra americana), and Black-necked Stilts (Himantopus mexicanus) were uncommon residents of San Francisco Bay, California (Grinnell and others, 1918; Grinnell and Wythe, 1927; Sibley, 1952). Presently, however, avocets and stilts are the two most abundant breeding shorebirds in San Francisco Bay (Stenzel and others, 2002; Rintoul and others, 2003). More than 4,000 avocets and 1,000 stilts, roughly 20 percent of their San Francisco Bay wintering populations, breed within the estuary, making San Francisco Bay the largest breeding area for these species on the Pacific Coast (Stenzel and others, 2002; Rintoul and others, 2003). Forster’s Terns were first observed breeding in the San Francisco Bay in 1948 (110 nests); they had increased to over 4000 individuals by the 1980s (Sibley, 1952; Gill, 1977; Harvey and others, 1992; Carter and others, 1990) and were estimated at 2000–3000 for 1998–2002; (Strong and others, 2004).It is hypothesized that the relatively large size of the current waterbird breeding populations is a result of the creation of artificial salt evaporation ponds from the 1930s through the 1950s (Gill, 1977; Goals Project, 1999). Until recently, these salt ponds and associated islands used by waterbirds for nesting have been managed relatively similarly and have supported large breeding waterbird populations. Recently, the South Bay Salt Pond Restoration Project has implemented plans to convert 50–90 percent of the 15,000 acres of salt ponds in the South San Francisco Bay back to tidal marsh habitat. Therefore, there is concern that the Restoration Project, while benefiting other native species, could negatively influence local breeding populations of waterbirds that are reliant on salt pond habitats for both breeding and foraging. A primary goal of the South Bay Salt Pond Restoration Project is to maintain current breeding waterbird populations (South Bay Salt Pond Long

Chesapeake Bay plume dynamics from LANDSAT

Science.gov (United States)

Munday, J. C., Jr.; Fedosh, M. S.

1981-01-01

LANDSAT images with enhancement and density slicing show that the Chesapeake Bay plume usually frequents the Virginia coast south of the Bay mouth. Southwestern (compared to northern) winds spread the plume easterly over a large area. Ebb tide images (compared to flood tide images) show a more dispersed plume. Flooding waters produce high turbidity levels over the shallow northern portion of the Bay mouth.

33 CFR 334.670 - Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing...

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Gulf of Mexico south and west of Apalachicola, San Blas, and St. Joseph bays; air-to-air firing practice range, Tyndall Air Force Base, Fla. 334..., DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.670 Gulf of Mexico south and west of...

Contrasting sedimentation patterns in two semi-enclosed mesotidal bays along the west and south coasts of Korea controlled by their orientation to the regional monsoon climate

Science.gov (United States)

Hong, Seok Hwi; Chun, Seung Soo; Chang, Tae Soo; Jang, Dae Geon

2017-08-01

Sedimentation patterns of tidal flats along the Korean west coast have long been known to be largely controlled by the monsoon climate. On the other hand, much less is known about the effect of the monsoon on sedimentation in coastal embayments with mouths of different geographic orientations. Good examples are Hampyeong and Yeoja bays along the west and south coasts, respectively. Both have narrow entrances, but their mouths open toward the northwest and the south, respectively. With mean tidal ranges of 3.46 and 3.2 m, respectively, the two bays experience similar tidal regimes and are hence excellent candidates to compare the effect of different exposure to the same regional monsoon climate on their respective sediment distribution patterns. The winter monsoon, in particular, is characterized by strong northwesterly winds that directly impact the west coast, but blow offshore along the south coast. For the purpose of this study, surficial sediment samples were collected from intertidal and subtidal flats of the two bays, both in summer and winter. Grain-size analyses were carried out by sieving (sand fraction) and Sedigraph (mud fraction). In the case of Yeoja Bay, the sediments consist mostly of mud (mean grain sizes of 5.4 to 8.8 phi). Seasonal changes are very subtle, the sediments being slightly coarser in summer when silt-dominated sediments are supplied by two streams to the northern parts of the bay in response to heavy rainfall. With the exception of the deeper tidal channels, Yeoja Bay is characterized by a thick mud blanket the year round, which is modulated by processes associated with the summer monsoon that predominantly blows from the east. Textural parameters suggest severely restricted sediment mixing on the subtidal and intertidal flats, the overall low energy situation preventing sands from reaching the tidal flats. The sediments of Hampyeong Bay, by contrast, are characterized by a distinct shoreward fining trend. Mean grain sizes average

Chondrichthyan occurrence and abundance trends in False Bay ...

African Journals Online (AJOL)

Commercial fishing in False Bay, South Africa, began in the 1600s. Today chondrichthyans are regularly taken in fisheries throughout the bay. Using a combination of catch, survey and life history data, the occurrence and long-term changes in populations of chondrichthyans in False Bay are described. Analyses of time ...

Coral bleaching on high-latitude marginal reefs at Sodwana Bay, South Africa

Energy Technology Data Exchange (ETDEWEB)

Celliers, Louis; Schleyer, Michael H

2002-12-01

Coral bleaching, involving the expulsion of symbiotic zooxanthellae from the host cells, poses a major threat to coral reefs throughout their distributional range. The role of temperature in coral bleaching has been extensively investigated and is widely accepted. A bleaching event was observed on the marginal high-latitude reefs of South Africa located at Sodwana Bay during the summer months of 2000. This was associated with increased sea temperatures with high seasonal peaks in summer and increased radiation in exceptionally clear water. The bleaching was limited to Two-mile Reef and Nine-mile Reef at Sodwana Bay and affected <12% of the total living cover on Two-mile Reef. Montipora spp., Alveopora spongiosa and Acropora spp. were bleached, as well as some Alcyoniidae (Sinularia dura, Lobophytum depressum, L. patulum). A cyclical increase in sea temperature (with a period of 5-6 years) was recorded during 1998-2000 in addition to the regional temperature increase caused by the El Nino Southern Oscillation phenomenon. The mean sea temperature increased at a rate of 0.27 deg. C year{sup -1} from May 1994 to April 2000. High maximum temperatures were measured (>29 deg. C). The lowest mean monthly and the mean maximum monthly temperatures at which coral bleaching occurred were 27.5 and 28.8 deg. C, respectively, while the duration for which high temperatures occurred in 2000 was 67 days at {>=}27.5 deg. C (4 days at {>=}28.8 deg. C). Increased water clarity and radiation appeared to be a synergistic cause in the coral bleaching encountered at Sodwana Bay.

Marine littoral diatoms from the Gordon’s bay region of False Bay, Cape Province, South Africa

CSIR Research Space (South Africa)

Giffen, MH

1971-01-01

Full Text Available and Comic/i for Scientific and Industrial Research, Pretoria (Received: 5.2. 1970) The Gordon?s Bay region occupies the north western corner of False Bay, a large rectangular bay, bounded on the west by the Cape Peninsula ending at Cape Point...

North Inlet • Winyah Bay (NIW) National Estuarine Research Reserve Meteorological Data, North Inlet Estuary, Georgetown, South Carolina: 1997 • 1999.

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 Winyah Bay Estuary were designated as part of the National Estuarine Research Reserve System...

Ecological study of the effects of power plants on benthic macroplant microcosms in subtropical and tropical estuaries. Progress report, 1976--1977

International Nuclear Information System (INIS)

Thorhaug, A.

1977-08-01

The effect of two fossil fuel and two nuclear plants on a near-shore seagrass community was studied in South Biscayne Bay, Dade County, Florida, over the past four years. The focus of the study was to delineate the effects that a series of various pollutants have had on the dominant system of seagrass Thalassia testudinum and its related community. Data are included from studies on the effects of heavy metals, waste heat, and dredging activities, with emphasis on thermal pollution. In order to separate the perturbation of the specific pollutant from the natural fluctuations of the system, efforts were made to understand the dynamic processes in adjacent untouched areas

33 CFR 334.660 - Gulf of Mexico and Apalachicola Bay south of Apalachicola, Fla., Drone Recovery Area, Tyndall Air...

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Gulf of Mexico and Apalachicola Bay south of Apalachicola, Fla., Drone Recovery Area, Tyndall Air Force Base, Fla. 334.660 Section 334... Apalachicola, Fla., Drone Recovery Area, Tyndall Air Force Base, Fla. (a) The restricted area. A rectangular...

78 FR 1246 - Otay River Estuary Restoration Project; South San Diego Bay Unit and Sweetwater Marsh Unit of the...

Science.gov (United States)

2013-01-08

...-FF08RSDC00] Otay River Estuary Restoration Project; South San Diego Bay Unit and Sweetwater Marsh Unit of the... scoping with regard to the environmental impact statement (EIS) for the proposed Otay River Estuary... one of the following methods. Email: [email protected] . Please include ``Otay Estuary NOI'' in the...

78 FR 56921 - South Bay Salt Pond Restoration Project, Phase 2 (Ponds R3, R4, R5, S5, A1, A2W, A8, A8S, A19...

Science.gov (United States)

2013-09-16

...-F2013227943] South Bay Salt Pond Restoration Project, Phase 2 (Ponds R3, R4, R5, S5, A1, A2W, A8, A8S, A19... South Bay Salt Pond Restoration Project and consists of restoring and enhancing over 2,000 acres of... Pollution Control Plant located at 700 Los Esteros Road, San Jose, California. The details of the public...

Dinoflagellate cysts from surface sediments of Saldanha Bay, South Africa: an indication of the potential risk of harmful algal blooms

CSIR Research Space (South Africa)

Joyce, LB

2005-02-01

Full Text Available Africa bZoology Department, University Cape Town, Rondebosch 7701, Cape Town, South Africa cCouncil for Scientific and Industrial Research, P.O. Box 320, Stellenbosch 7759, South Africa Received 14 May 2004; received in revised form 21 July 2004; accepted... 15 August 2004 Abstract The distribution and abundance of dinoflagellate cysts from recent coastal sediments in Saldanha Bay, was investigated, and compared to the cyst assemblages of the adjacent coastal upwelling system as reflected in the sediments...

Illumina-based analysis the microbial diversity associated with Thalassia hemprichii in Xincun Bay, South China Sea.

Science.gov (United States)

Jiang, Yu-Feng; Ling, Juan; Dong, Jun-De; Chen, Biao; Zhang, Yan-Ying; Zhang, Yuan-Zhou; Wang, You-Shao

2015-10-01

In order to increase our understanding of the microbial diversity associated with seagrass Thalassia hemprichii in Xincun Bay, South China Sea, 16S rRNA gene was identified by highthrough sequencing method. Bacteria associated with seagrass T. hemprichii belonged to 37 phyla, 99 classes. The diversity of bacteria associated with seagrass was similar among the geographically linked coastal locations of Xincun Bay. Proteobacteria was the dominant bacteria and the α-proteobacteria had adapted to the seagrass ecological niche. As well, α-proteobacteria and Pseudomonadales were associated microflora in seagrass meadows, but the interaction between the bacteria and plant is needed to further research. Burkholderiales and Verrucomicrobiae indicated the influence of the bay from anthropogenic activities. Further, Cyanobacteria could imply the difference of the nutrient conditions in the sites. γ-proteobacteria, Desulfobacterales and Pirellulales played a role in the cycle of sulfur, organic mineralization and meadow ecosystem, respectively. In addition, the less abundance bacteria species have key functions in the seagrass meadows, but there is lack knowledge of the interaction of the seagrass and less abundance bacteria species. Microbial communities can response to surroundings and play key functions in the biochemical cycle.

The Holocene History of Placentia Bay, Newfoundland

DEFF Research Database (Denmark)

Sheldon, Christina; Seidenkrantz, Marit-Solveig; Reynisson, Njall

2013-01-01

Marine sediments analyzed from cores taken in Placentia Bay, Newfoundland, located in the Labrador Sea, captured oceanographic and climatic changes from the end of the Younger Dryas through the Holocene. Placentia Bay is an ideal site to capture changes in both the south-flowing Labrador Current ...

A conceptual hydrologic model for a forested Carolina bay depressional wetland on the Coastal Plain of South Carolina, USA

Science.gov (United States)

Jennifer E. Pyzoha; Timothy J. Callahan; Ge Sun; Carl C. Trettin; Masato Miwa

2008-01-01

This paper describes how climate influences the hydrology of an ephemeral depressional wetland. Surface water and groundwater elevation data were collected for 7 years in a Coastal Plain watershed in South Carolina USA containing depressional wetlands, known as Carolina bays. Rainfall and temperature data were compared with water-table well and piezometer data in and...

IBBEAM- EPIFAUNA

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Biscayne Bay is near the downstream end of the massive Southern and Central Florida Water Management System, which is being modified by the Comprehensive Everglades...

Mangrove Study Data

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Southern Biscayne Bay's shoreline fish community been monitored visually twice a year since 1998 to compare fish use of mangrove prop root habitats along the...

Trends and habitat associations of waterbirds using the South Bay Salt Pond Restoration Project, San Francisco Bay, California

Science.gov (United States)

De La Cruz, Susan E. W.; Smith, Lacy M.; Moskal, Stacy M.; Strong, Cheryl; Krause, John; Wang, Yiwei; Takekawa, John Y.

2018-04-02

Executive SummaryThe aim of the South Bay Salt Pond Restoration Project (hereinafter “Project”) is to restore 50–90 percent of former salt evaporation ponds to tidal marsh in San Francisco Bay (SFB). However, hundreds of thousands of waterbirds use these ponds over winter and during fall and spring migration. To ensure that existing waterbird populations are supported while tidal marsh is restored in the Project area, managers plan to enhance the habitat suitability of ponds by adding islands and berms to change pond topography, manipulating water salinity and depth, and selecting appropriate ponds to maintain for birds. To help inform these actions, we used 13 years of monthly (October–April) bird abundance data from Project ponds to (1) assess trends in waterbird abundance since the inception of the Project, and (2) evaluate which pond habitat characteristics were associated with highest abundances of different avian guilds and species. For comparison, we also evaluated waterbird abundance trends in active salt production ponds using 10 years of monthly survey data.We assessed bird guild and species abundance trends through time, and created separate trend curves for Project and salt production ponds using data from every pond that was counted in a year. We divided abundance data into three seasons—fall (October–November), winter (December–February), and spring (March–April). We used the resulting curves to assess which periods had the highest bird abundance and to identify increasing or decreasing trends for each guild and species.

Proceedings of the SERDP Coral Reef Monitoring and Assessment Workshop

Science.gov (United States)

2009-12-01

the U.S. that have coral reefs within their jurisdictions. Biscayne National Park, the Dry Tortugas , and U.S. Virgin Island parks at St. John and...Signs Monitoring Networks Dry Tortugas NP Buck Island Reef NM Virgin Islands National Park Biscayne NP South Florida/Caribbean Network Florida/Caribbean...Buck Island, Dry Tortugas and Biscayne • Extensive sites – 4 10m permanent transects per site – 18 sites in DRTO Virgin Islands NP % l i v e c o r

Assessment of occupational exposure to BTEX compounds at a bus diesel-refueling bay: A case study in Johannesburg, South Africa.

Science.gov (United States)

Moolla, Raeesa; Curtis, Christopher J; Knight, Jasper

2015-12-15

Of increasing concern is pollution by volatile organic compounds, with particular reference to five aromatic hydrocarbons (benzene, toluene, ethyl benzene and two isomeric xylenes; BTEX). These pollutants are classified as hazardous air pollutants. Due to the potential health risks associated with these pollutants, BTEX concentrations were monitored at a bus diesel-refueling bay, in Johannesburg, South Africa, using gas chromatography, coupled with a photo-ionization detector. Results indicate that o-xylene (29-50%) and benzene (13-33%) were found to be the most abundant species of total BTEX at the site. Benzene was within South African occupational limits, but above international occupational exposure limits. On the other hand, occupational concentrations of toluene, ethyl-benzene and xylenes were within national and international occupational limits throughout the monitoring period, based on 8-hour workday weighted averages. Ethyl-benzene and p-xylene concentrations, during winter, correspond to activity at the site, and thus idling of buses during refueling may elevate results. Overall, occupational air quality at the refueling bay is a matter of health concern, especially with regards to benzene exposure, and future reduction strategies are crucial. Discrepancies between national and international limit values merit further investigation to determine whether South African guidelines for benzene are sufficiently precautionary. Copyright © 2015 Elsevier B.V. All rights reserved.

Algae Reefs in Shark Bay, Western Australia, Australia

Science.gov (United States)

1990-01-01

Numerous algae reefs are seen in Shark Bay, Western Australia, Australia (26.0S, 113.5E) especially in the southern portions of the bay. The south end is more saline because tidal flow in and out of the bay is restricted by sediment deposited at the north and central end of the bay opposite the mouth of the Wooramel River. This extremely arid region produces little sediment runoff so that the waters are very clear, saline and rich in algae.

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

Hyperspectral Biofilm Classification Analysis for Carrying Capacity of Migratory Birds in the South Bay Salt Ponds

Science.gov (United States)

Hsu, Wei-Chen; Kuss, Amber Jean; Ketron, Tyler; Nguyen, Andrew; Remar, Alex Covello; Newcomer, Michelle; Fleming, Erich; Debout, Leslie; Debout, Brad; Detweiler, Angela;

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

Residency, Habitat Use and Sexual Segregation of White Sharks, Carcharodon carcharias in False Bay, South Africa

Science.gov (United States)

Kock, Alison; O’Riain, M. Justin; Mauff, Katya; Meÿer, Michael; Kotze, Deon; Griffiths, Charles

2013-01-01

White sharks (Carcharodon carcharias) are threatened apex predators and identification of their critical habitats and how these are used are essential to ensuring improved local and ultimately global white shark protection. In this study we investigated habitat use by white sharks in False Bay, South Africa, using acoustic telemetry. 56 sharks (39 female, 17 male), ranging in size from 1.7–5 m TL, were tagged with acoustic transmitters and monitored on an array of 30 receivers for 975 days. To investigate the effects of season, sex and size on habitat use we used a generalized linear mixed effects model. Tagged sharks were detected in the Bay in all months and across all years, but their use of the Bay varied significantly with the season and the sex of the shark. In autumn and winter males and females aggregated around the Cape fur seal colony at Seal Island, where they fed predominantly on young of the year seals. In spring and summer there was marked sexual segregation, with females frequenting the Inshore areas and males seldom being detected. The shift from the Island in autumn and winter to the Inshore region in spring and summer by females mirrors the seasonal peak in abundance of juvenile seals and of migratory teleost and elasmobranch species respectively. This study provides the first evidence of sexual segregation at a fine spatial scale and demonstrates that sexual segregation in white sharks is not restricted to adults, but is apparent for juveniles and sub-adults too. Overall, the results confirm False Bay as a critical area for white shark conservation as both sexes, across a range of sizes, frequent the Bay on an annual basis. The finding that female sharks aggregate in the Inshore regions when recreational use peaks highlights the need for ongoing shark-human conflict mitigation strategies. PMID:23383052

Bird surveys at McKinley Bay and Hutchison Bay, Northwest Territories, in 1991

Energy Technology Data Exchange (ETDEWEB)

Cornish, B J; Dickson, D L; Dickson, H L

1992-03-01

McKinley Bay is a shallow protected bay along the eastern Beaufort Sea coast which provides an important habitat for diving ducks. Since 1979, the bay has been the site of a winter harbor and support base for oil and gas exploraton in the Beaufort Sea. Aerial surveys for bird abundance and distribution were conducted in August 1991 as a continuation of long-term monitoring of birds in McKinley Bay and Hutchison Bay, a nearby area used as a control. The main objectives of the 1991 surveys were to expand the set of baseline data on natural annual fluctuations in diving duck numbers, and to determine if numbers of diving ducks had changed since the initial 1981-85 surveys. On the day with the best survey conditions, the population of diving ducks at McKinley bay was estimated at ca 32,000, significantly more than 1981-85. At Hutchison Bay, there were an estimated 11,000 ducks. As in previous years, large numbers of diving ducks were observed off Atkinson Point at the northwest corner of McKinley Bay, at the south end of the bay, and in the northeast corner near a long spit. Most divers in Hutchison Bay were at the west side. Diving ducks, primarily Oldsquaw and scoter, were the most abundant bird group in the study area. Observed distribution patterns of birds are discussed with reference to habitat preferences. 16 refs., 7 figs., 30 tabs.

The influence of finfish aquaculture on benthic fish and crustacean assemblages in Fitzgerald Bay, South Australia

Directory of Open Access Journals (Sweden)

Jason E. Tanner

2015-09-01

Full Text Available The influence of sea-cage aquaculture on wildfish assemblages has received little attention outside of Europe. Sea-cage aquaculture of finfish is a major focus in South Australia, and while the main species farmed is southern bluefin tuna (Thunnus maccoyii, there is also an important yellowtail kingfish (Seriola lalandi industry. Yellowtail kingfish aquaculture did not appear to have any local or regional effects on demersal assemblages (primarily fish, but also some crustaceans surveyed by baited remote underwater video (BRUV in Fitzgerald Bay. We did, however, detect small scale spatial variations in assemblages within the bay. The type of bait used strongly influenced the assemblage recorded, with significantly greater numbers of fish attracted to deployments where sardines were used as the bait to compared to those with no bait. The pelleted feed used by the aquaculture industry was just as attractive as sardines at one site, and intermediate between sardines and no bait at the other. There was significant temporal variability in assemblages at both farm sites and one control site, while the second control site was temporally stable (over the 9 weeks of the study. Overall, the results suggested that aquaculture was having little if any impact on the abundance and assemblage structure of the demersal macrofauna in Fitzgerald Bay.

NUMERICAL MODELS AS TOOLS TO UNDERSTAND THE DYNAMICS IN BAYS: CASE OF STUDY CHETUMAL BAY, QUINTANA ROO

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David Avalos-Cueva

2017-07-01

Full Text Available In this study performed the simulation of currents generated by the wind on the Bay of Chetumal, Quintana Roo through the use of a stationary shallow-water model. A homogeneous climatic wind was used for the entire Bay, with a velocity of 3m·s-1 , and directions North, South, Northeast, Northwest, East, Southeast, Southwest and West. The results showed a rather complex dynamics in Chetumal Bay, in which important turns were observed in deep areas, with speeds reaching up to 13 cm·s-1 .

Variability in the air–sea interaction patterns and timescales within the south-eastern Bay of Biscay, as observed by HF radar data

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A. Fontán

2013-04-01

Full Text Available Two high-frequency (HF radar stations were installed on the coast of the south-eastern Bay of Biscay in 2009, providing high spatial and temporal resolution and large spatial coverage of currents in the area for the first time. This has made it possible to quantitatively assess the air–sea interaction patterns and timescales for the period 2009–2010. The analysis was conducted using the Barnett–Preisendorfer approach to canonical correlation analysis (CCA of reanalysis surface winds and HF radar-derived surface currents. The CCA yields two canonical patterns: the first wind–current interaction pattern corresponds to the classical Ekman drift at the sea surface, whilst the second describes an anticyclonic/cyclonic surface circulation. The results obtained demonstrate that local winds play an important role in driving the upper water circulation. The wind–current interaction timescales are mainly related to diurnal breezes and synoptic variability. In particular, the breezes force diurnal currents in waters of the continental shelf and slope of the south-eastern Bay. It is concluded that the breezes may force diurnal currents over considerably wider areas than that covered by the HF radar, considering that the northern and southern continental shelves of the Bay exhibit stronger diurnal than annual wind amplitudes.

Pink shrimp as an indicator for restoration of everglades ecosystems

Science.gov (United States)

Browder, Joan A.; Robblee, M.B.

2009-01-01

The pink shrimp, Farfantepenaeus duorarum, familiar to most Floridians as either food or bait shrimp, is ubiquitous in South Florida coastal and offshore waters and is proposed as an indicator for assessing restoration of South Florida's southern estuaries: Florida Bay, Biscayne Bay, and the mangrove estuaries of the lower southwest coast. Relationships between pink shrimp and salinity have been determined in both field and laboratory studies. Salinity is directly relevant to restoration because the salinity regimes of South Florida estuaries, critical nursery habitat for the pink shrimp, will be altered by changes in the quantity, timing, and distribution of freshwater inflow planned as part of the Comprehensive Everglades Restoration Project (CERP). Here we suggest performance measures based on pink shrimp density (number per square meter) in the estuaries and propose a restoration assessment and scoring scheme using these performance measures that can readily be communicated to managers, policy makers, and the interested public. The pink shrimp is an appropriate restoration indicator because of its ecological as well as its economic importance and also because scientific interest in pink shrimp in South Florida has produced a wealth of information about the species and relatively long time series of data on both juveniles in estuarine nursery habitats and adults on the fishing grounds. We suggest research needs for improving the pink shrimp performance measure.

Diachronic Change within the Still Bay at Blombos Cave, South Africa.

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Will Archer

Full Text Available Characteristically shaped bifacial points are stone artefacts with which the Middle Stone Age Still Bay techno-complex in Southern Africa is identified. Traditional approaches such as chaîne opératoire and two-dimensional metrics in combination with attribute analyses have been used to analyse variability within Still Bay point assemblages. Here we develop a protocol to extract and analyse high resolution 3-dimensional geometric morphometric information about Still Bay point morphology. We also investigate ways in which the independent variables of time, raw-material and tool size may be driving patterns of shape variation in the Blombos Cave point assemblage. We demonstrate that at a single, stratified Still Bay site points undergo significant modal changes in tool morphology and standardization. Our results caution against (1 treatment of the Still Bay as a static technological entity and (2 drawing demographic inferences stemming from grouping Still Bay point collections within the same cultural label.

Geochemical of trace elements in volcanics rocks Peninsula Fildes, Fildes Bay Rey Jorge island, south Shetland

International Nuclear Information System (INIS)

Masquelin, H.; Vaz Chavez, N.

1987-01-01

The authors present some geochemical data derived from the multielement analysis of three different types of volcanic rocks collected around Fildes Bay on King George Island, South Shetland. Volcanic rocks from Fildes Peninsula Group may be distinguished from those Marian Cove by their hydrothermal alteration. Apparently the correlation between NI ands Cr allows for the observation of the stratigraphic separation of samples of the same kind. Consequently, the correlation between Cu and As show a distinction between Marian Cove propylitised tuffites and both Brecciated Andesites and pyroclastic rock from Fildes Peninsula Group.

77 FR 43514 - Anchorage Regulations; Narragansett Bay and Rhode Island Sound, RI

Science.gov (United States)

2012-07-25

...-AA01 Anchorage Regulations; Narragansett Bay and Rhode Island Sound, RI AGENCY: Coast Guard, DHS... Narragansett Bay, Rhode Island, and adding an offshore anchorage in Rhode Island Sound south of Brenton Point... rulemaking (NPRM) entitled ``Anchorage Regulations; Narragansett Bay and Rhode Island Sound, RI,'' in the...

Is the biological productivity in the Bay of Bengal light limited?

Digital Repository Service at National Institute of Oceanography (India)

PrasannaKumar, S.; Narvekar, J.; Nuncio, M.; Kumar, A.; Ramaiah, N.; Sardessai, S.; Gauns, M.; Fernandes, V.; Paul, J.

Recent measurements of chlorophyll, primary productivity (PP) and nutrients along the central Bay of Bengal (BOB) during summer, fall and spring intermonsoons showed that the northern bay becomes less productive compared to the south in summer...

Petroleum Hydrocarbon Profiles of Water and Sediment of Algoa Bay, Eastern Cape, South Africa

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Abiodun O. Adeniji

2017-10-01

Full Text Available Petroleum hydrocarbon profiles of water and sediment samples of Algoa Bay in the Eastern Cape Province of South Africa were assessed using standard analytical procedures. Water (from surface and bottom levels and sediment samples were collected from five locations in the bay from February to June 2016. Extraction of the petroleum hydrocarbons from the water and sediment samples collected was achieved using liquid-liquid and Soxhlet extraction techniques, respectively, followed by column clean up. Target compounds were analytically determined with gas chromatography–flame ionization detector (GC-FID and quantified by integrating the areas of both the resolved and unresolved components. Physicochemical properties of the water samples were also determined on site using a SeaBird 19plusV2 CTD SBE 55 device. Estimated limit of detection, limit of quantitation and relative standard deviation for the 35 n-alkane standards ranged from 0.06 to 0.13 μg/L, 0.30 to 0.69 μg/L and 3.61 to 8.32%, respectively. Results showed that total petroleum hydrocarbon (TPH varied from 45.07 to 307 μg/L in the water and 0.72 to 27.03 mg/kg in the sediments. The mean concentrations of TPH in both the water and sediment samples from Algoa Bay revealed a slight level of pollution. The diagnostic indices used showed that the hydrocarbons in the area were from both biogenic and anthropogenic sources. Hence, there is need for adequate regulation and control of all activities contributing to the levels of petroleum hydrocarbon in the marine environment for the safety of human, aquatic and wild lives in the area.

Petroleum Hydrocarbon Profiles of Water and Sediment of Algoa Bay, Eastern Cape, South Africa.

Science.gov (United States)

Adeniji, Abiodun O; Okoh, Omobola O; Okoh, Anthony I

2017-10-20

Petroleum hydrocarbon profiles of water and sediment samples of Algoa Bay in the Eastern Cape Province of South Africa were assessed using standard analytical procedures. Water (from surface and bottom levels) and sediment samples were collected from five locations in the bay from February to June 2016. Extraction of the petroleum hydrocarbons from the water and sediment samples collected was achieved using liquid-liquid and Soxhlet extraction techniques, respectively, followed by column clean up. Target compounds were analytically determined with gas chromatography-flame ionization detector (GC-FID) and quantified by integrating the areas of both the resolved and unresolved components. Physicochemical properties of the water samples were also determined on site using a SeaBird 19plusV2 CTD SBE 55 device. Estimated limit of detection, limit of quantitation and relative standard deviation for the 35 n -alkane standards ranged from 0.06 to 0.13 μg/L, 0.30 to 0.69 μg/L and 3.61 to 8.32%, respectively. Results showed that total petroleum hydrocarbon (TPH) varied from 45.07 to 307 μg/L in the water and 0.72 to 27.03 mg/kg in the sediments. The mean concentrations of TPH in both the water and sediment samples from Algoa Bay revealed a slight level of pollution. The diagnostic indices used showed that the hydrocarbons in the area were from both biogenic and anthropogenic sources. Hence, there is need for adequate regulation and control of all activities contributing to the levels of petroleum hydrocarbon in the marine environment for the safety of human, aquatic and wild lives in the area.

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Biscayne Bay Dolphin Photo ID System

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National Oceanic and Atmospheric Administration, Department of Commerce — It has been shown through a variety of photo-identification studies that populations of bottlenose dolphin inhabit the various embayments along the coast of Florida....

Latest results from Daya Bay

Science.gov (United States)

Vorobel, Vit; Daya Bay Collaboration

2017-07-01

The Daya Bay Reactor Neutrino Experiment was designed to measure θ 13, the smallest mixing angle in the three-neutrino mixing framework, with unprecedented precision. The experiment consists of eight functionally identical detectors placed underground at different baselines from three pairs of nuclear reactors in South China. Since Dec. 2011, the experiment has been running stably for more than 4 years, and has collected the largest reactor anti-neutrino sample to date. Daya Bay is able to greatly improve the precision on θ 13 and to make an independent measurement of the effective mass splitting in the electron antineutrino disappearance channel. Daya Bay can also perform a number of other precise measurements, such as a high-statistics determination of the absolute reactor antineutrino flux and spectrum, as well as a search for sterile neutrino mixing, among others. The most recent results from Daya Bay are discussed in this paper, as well as the current status and future prospects of the experiment.

Geologic framework studies of South Carolina's Long Bay from Little River Inlet to Winyah Bay, 1999-2003: geospatial data release

Science.gov (United States)

Baldwin, W.E.; Denny, J.F.; Schwab, W.C.; Gayes, P.T.; Morton, R.; Driscoll, N.W.

2007-01-01

offshore of the northern South Carolina coast. The digital data presented herein accompany USGS Open-File Reports OFR 2004-1013 and OFR 2005-1345, describing the stratigraphic framework and modern sediment distribution within Long Bay, respectively. Direct on-line links to these publications are available within 'References' on the navigation bar to the left. Additional links to other publications and web sites are also available.

Electrical resistivity and porosity structure of the upper Biscayne Aquifer in Miami-Dade County, Florida

Science.gov (United States)

Whitman, Dean; Yeboah-Forson, Albert

2015-12-01

Square array electrical soundings were made at 13 sites in the Biscayne Aquifer distributed between 1 and 20 km from the shoreline. These soundings were modeled to investigate how resistivity varies spatially and with depth in the upper 15 m of the aquifer. Porosity was estimated from the modeled formation resistivity and observed pore fluid resistivity with Archie's Law. The models were used to interpolate resistivity and porosity surfaces at -2, -5, -8, and -15 m elevations. Modeled resistivity in the unsaturated zone is generally higher than 300 Ω m with the resistivity at sites with thick unsaturated zones greater than 1000 Ω m. Resistivity in the saturated zone ranges from 30 to 320 Ω m. At many sites in the western portions of the study area, resistivity is constant or increases with depth whereas sites in the center of the Atlantic Coastal Ridge exhibit a distinct low resistivity zone (ρ aquifer. The estimated porosity ranges between 14% and 71% with modal values near 25%. The porosity structure varies both with depth and spatially. Western sites exhibit a high porosity zone at shallow depths best expressed in a NE-SW trending zone of 40-50% porosity situated near the western margin of the Atlantic Coastal Ridge. This zone roughly corresponds in depth with the Q5 chronostratigraphic unit of the Miami Fm. which constitutes the upper flow unit of the Biscayne Aquifer. The highest porosity (>50%) is seen at elevations below -5 m at sites in the center of the Atlantic Coastal Ridge and likely corresponds to solution features. The general NE-SW trend of the resistivity and porosity structure suggests a causal connection with the Pleistocene paleogeography and sedimentary environments.

Responses of upland herpetofauna to the restoration of Carolina Bays and thinning of forested Bay Margins.

Energy Technology Data Exchange (ETDEWEB)

Ledvina, Joseph A.

2008-05-01

Research on the effects of wetland restoration on reptiles and amphibians is becoming more common, but almost all of these studies have observed the colonization of recently disturbed habitats that were completely dry at the time of restoration. In a similar manner, investigations herpetofaunal responses to forest management have focused on clearcuts, and less intensive stand manipulations are not as well studied. To evaluate community and population responses of reptiles and amphibians to hydrology restoration and canopy removal in the interior of previously degraded Carolina bays, I monitored herpetofauna in the uplands adjacent to six historically degraded Carolina bays at the Savannah River Site (SRS) in South Carolina for four years after restoration. To evaluate the effects of forest thinning on upland herpetofauna, forests were thinned in the margins of three of these bays. I used repeated measures ANOVA to compare species richness and diversity and the abundance of selected species and guilds between these bays and with those at three reference bays that were not historically drained and three control bays that remained degraded. I also used Non-metric Multidimensional Scaling (NMDS) to look for community-level patterns based treatments.

Difference of nitrogen-cycling microbes between shallow bay and deep-sea sediments in the South China Sea.

Science.gov (United States)

Yu, Tiantian; Li, Meng; Niu, Mingyang; Fan, Xibei; Liang, Wenyue; Wang, Fengping

2018-01-01

In marine sediments, microorganisms are known to play important roles in nitrogen cycling; however, the composition and quantity of microbes taking part in each process of nitrogen cycling are currently unclear. In this study, two different types of marine sediment samples (shallow bay and deep-sea sediments) in the South China Sea (SCS) were selected to investigate the microbial community involved in nitrogen cycling. The abundance and composition of prokaryotes and seven key functional genes involved in five processes of the nitrogen cycle [nitrogen fixation, nitrification, denitrification, dissimilatory nitrate reduction to ammonium (DNRA), and anaerobic ammonia oxidation (anammox)] were presented. The results showed that a higher abundance of denitrifiers was detected in shallow bay sediments, while a higher abundance of microbes involved in ammonia oxidation, anammox, and DNRA was found in the deep-sea sediments. Moreover, phylogenetic differentiation of bacterial amoA, nirS, nosZ, and nrfA sequences between the two types of sediments was also presented, suggesting environmental selection of microbes with the same geochemical functions but varying physiological properties.

Gradient Analysis and Classification of Carolina Bay Vegetation: A Framework for Bay Wetlands Conservation and Restoration

Energy Technology Data Exchange (ETDEWEB)

Diane De Steven,Ph.D.; Maureen Tone,PhD.

1997-10-01

This report address four project objectives: (1) Gradient model of Carolina bay vegetation on the SRS--The authors use ordination analyses to identify environmental and landscape factors that are correlated with vegetation composition. Significant factors can provide a framework for site-based conservation of existing diversity, and they may also be useful site predictors for potential vegetation in bay restorations. (2) Regional analysis of Carolina bay vegetation diversity--They expand the ordination analyses to assess the degree to which SRS bays encompass the range of vegetation diversity found in the regional landscape of South Carolina's western Upper Coastal Plain. Such comparisons can indicate floristic status relative to regional potentials and identify missing species or community elements that might be re-introduced or restored. (3) Classification of vegetation communities in Upper Coastal Plain bays--They use cluster analysis to identify plant community-types at the regional scale, and explore how this classification may be functional with respect to significant environmental and landscape factors. An environmentally-based classification at the whole-bay level can provide a system of templates for managing bays as individual units and for restoring bays to desired plant communities. (4) Qualitative model for bay vegetation dynamics--They analyze present-day vegetation in relation to historic land uses and disturbances. The distinctive history of SRS bays provides the possibility of assessing pathways of post-disturbance succession. They attempt to develop a coarse-scale model of vegetation shifts in response to changing site factors; such qualitative models can provide a basis for suggesting management interventions that may be needed to maintain desired vegetation in protected or restored bays.

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. Copyright © 2014 Elsevier Ltd. All rights reserved.

Turkey Point tritium. Progress report

International Nuclear Information System (INIS)

Ostlund, H.G.; Dorsey, H.G.

1976-01-01

In 1972-73 the Florida Power and Light Company (FPL) began operation of two nuclear reactors at Turkey Point on lower Biscayne Bay. One radioactive by-product resulting from the operation of the nuclear reactors, tritium, provides a unique opportunity to study transport and exchange processes on a local scale. Since the isotope in the form of water is not removed from the liquid effluent, it is discharged to the cooling canal system. By studying its residence time in the canal and the pathways by which it leaves the canals, knowledge of evaporative process, groundwater movement, and bay exchange with the ocean can be obtained. Preliminary results obtained from measurement of tritium levels, both in the canal system and in the surrounding environment are discussed. Waters in lower Biscayne Bay and Card and Barnes Sounds receive only a small portion of the total tritium produced by the nuclear plant. The dominating tritium loss most likely is through evaporation from the canals. The capability of measuring extremely low HTO levels allows the determination of the evaporation rate experimentally by measuring the tritium levels of air after having passed over the canals

Sepetiba Bay: an integrated study of an harbour location

International Nuclear Information System (INIS)

Bandeira, J.V.; Aun, P.E.; Castro, J.O.N.M. de; Moreira, R.M.

1984-01-01

Several aspects of the construction of an iron-ore and coal terminal in Sepetiba bay (RJ, Brazil) in the region of south of Madeira Island, are presented. The studies include a general view of the geomorphology of the region, analyses of current measurements, water circulation and sedimentology of the bay by conventional methods and by radioactive tracers. (M.A.C.) [pt

Distribution of radionuclides in a marine sediment core off the waterspout of the nuclear power plants in Daya Bay, northeastern South China Sea.

Science.gov (United States)

Zhou, Peng; Li, Dongmei; Li, Haitao; Fang, Hongda; Huang, Chuguang; Zhang, Yusheng; Zhang, Hongbiao; Zhao, Li; Zhou, Junjie; Wang, Hua; Yang, Jie

2015-07-01

A sediment core was collected and dated using (210)Pbex dating method off the waterspout of nuclear power base of Daya Bay, northeastern South China Sea. The γ-emitting radionuclides were analyzed using HPGe γ spectrometry, gross alpha and beta radioactivity as well as other geochemical indicators were deliberated to assess the impact of nuclear power plants (NPP) operation and to study the past environment changes. It suggested that NPP provided no new radioactivity source to sediment based on the low specific activity of (137)Cs. Two broad peaks of TOC, TC and LOI accorded well with the commercial operations of Daya Bay NPP (1994.2 and 1994.5) and LNPP Phase I (2002.5 and 2003.3), implying that the mass input of cooling water from NPP may result into a substantial change in the ecological environment and Daya Bay has been severely impacted by human activities. Copyright © 2015 Elsevier Ltd. All rights reserved.

Destruction of the Phoenix/Hibiscus and Barringtonia racemosa Communities at Richards Bay, Natal, South Africa

Directory of Open Access Journals (Sweden)

P. J. Weisser

1982-10-01

Full Text Available The destruction of the Phoenix!Hibiscus and Barringtonia racemosa Communities described by Venter in 1972 on the southern shores of Richards Bay is reported. The cause was the artificial openingof a new mouth about 5,5 km south of the original mouth, which increased tidal range and salinity. These swamp communities occupied a narrow band about 6 ha in area behind the Bruguiera gymnorrhiza Community. An estimated 95 % of the communities was affected and only on the landward border were some isolated remnants of species such as Acrostichum aureum, Hibiscus tiliaceus and Phoenix reclinata detected .Young stands of  Phragmites australis, seedlings of  Bruguiera gymnorrhiza and Avicennia marina and epipelic algae are recoIonizing the affected area.

76 FR 31846 - Safety Zone; 28th Annual Humboldt Bay Festival, Fireworks Display, Eureka, CA

Science.gov (United States)

2011-06-02

...-AA00 Safety Zone; 28th Annual Humboldt Bay Festival, Fireworks Display, Eureka, CA AGENCY: Coast Guard... support of the 28th Annual Humboldt Bay Festival Fireworks Display on the specified waters off the South... Humboldt Bay Festival Fireworks Display. The fireworks display is for entertainment purposes. This safety...

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

Science.gov (United States)

Aretxabaleta, Alfredo; Ganju, Neil K.; 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.

Establishment and extinction of a population of South Georgian diving petrel (Pelecanoides georgicus) at Mason Bay, Stewart Island, New Zealand, during the late Holocene

International Nuclear Information System (INIS)

Holdaway, R.N.; Jones, M.D.; Beavan Athfield, N.R.

2003-01-01

A population of South Georgian diving petrels (Pelecanoides georgicus) (c. 130 g) became extinct at Mason Bay, on the west coast of Stewart Island, before European settlement. Pacific rat (Rattus exulans) bones with the diving petrel fossils provided an opportunity to determine whether the rats arrived before the petrels went extinct. Fifteen 14 C accelerator mass spectrometry (AMS) ages on purified diving petrel bone gelatin from various parts of Mason Bay clustered unexpectedly in the 14th and 15th centuries AD, and none was older. Bayesian statistical analysis, using a Markov Chain Monte Carlo procedure, gave a 95% probability that the diving petrel colony was founded between 1338 and 1440 AD, lasted 40-310 years, and became extinct between 1475 and 1650 AD. Possible reasons for the late colonisation of Mason Bay by South Georgian diving petrels burrow are discussed. Bayesian analysis of five 14 C AMS determinations on Pacific rat bone gelatin did not exclude the possibility that the Pacific rat arrived before the diving petrel colony was established. However, the enriched δ 13 C of their bone gelatin suggests that the rats had a partially marine diet, and a terrestrial calibration procedure for their AMS ages was probably not appropriate. The Pacific rat is likely to have arrived after the diving petrel colony became established and probably caused the bird's extinction after a short period of coexistence. (author). 103 refs., 3 figs., 5 tabs

Relations between well-field pumping and induced canal leakage in east-central Miami-Dade County, Florida, 2010-2011

Science.gov (United States)

Nemec, Katherine; Antolino, Dominick J.; Turtora, Michael; Adam Foster,

2015-08-26

An extensive canal and water management system exists in south Florida to prevent flooding, replenish groundwater, and impede saltwater intrusion. The unconfined Biscayne aquifer, which underlies southeast Florida and provides water for millions of residents, interacts with the canal system. The Biscayne aquifer is composed of a highly transmissive karst limestone; therefore, canal stage and flow may be affected by production well pumping, especially in locations where production wells and canals are in proximity.

Temperature profile and other data collected from XBT casts in South Pacific Ocean from BOTANY BAY and other platforms from 24 January 1991 to 20 November 1991 (NODC Accession 9400208)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Temperature profile and other data were collected using XBT casts from BOTANY BAY and other platforms in South Pacific Ocean. Data were collected from 24 January...

Arbovirus circulation, temporal distribution, and abundance of mosquito species in two Carolina bay habitats.

Science.gov (United States)

Ortiz, D I; Wozniak, A; Tolson, M W; Turner, P E

2005-01-01

Carolina bays, a type of geomorphic feature, may be important in the ecology of mosquito vectors in South Carolina. Their hydrology varies from wetland habitats with marked flooding/drying regimes to permanently flooded spring-fed lakes. Moreover, they possess characteristics that contribute to the support of a particularly abundant and diverse invertebrate fauna. Although it has been estimated that 2,700+ bays exist in South Carolina, approximately 97% have been altered; Heritage Preserve (SBHP) and Woods Bay State Park (WBSP), from June 1997 to July 1998 to determine mosquito temporal distribution, species composition, and the occurrence of arbovirus activity. The largest mosquito collection was obtained at WBSP (n = 31,172) representing 25 species followed by SBHP (n = 3,940) with 24 species. Anopheles crucians complex were the most common species encountered in both bays. Two virus isolates were obtained from SBHP in 1997: Keystone (KEY) virus from Ochlerotatus atlanticus-tormentor and Cache Valley (CV) virus from Oc. canadensis canadensis. Twenty-nine (29) arbovirus-positive pools were obtained from WBSP: 28 in 1997 and one in 1998. KEY virus was isolated from three pools of Oc. atlanticus-tormentor and Tensaw (TEN) virus was isolated from two pools of An. crucians complex; 10 isolates could not be identified with the sera available. Additionally, 14 pools of An. crucians complex tested positive for Eastern equine encephalitis (EEE) virus antigen. These represent the first record of KEY and CV viruses in South Carolina. Our data indicate the presence of high mosquito density and diversity in both Carolina bay habitats, which may be influenced, in part, by seasonal changes in their hydroperiods. The study of mosquito and arbovirus ecology in Carolina Bay habitats could provide more information on the transmission dynamics of arboviruses and its impact on human and animal arboviral disease occurrence in South Carolina.

Near Surface Geophysical Investigations of Potential Direct Recharge Zones in the Biscayne Aquifer within Everglades National Park, Florida.

Science.gov (United States)

Mount, G.; Comas, X.

2017-12-01

The karstic Miami Limestone of the Biscayne aquifer is characterized as having water flow that is controlled by the presence of dissolution enhanced porosity and mega-porous features. The dissolution features and other high porosity areas create horizontal preferential flow paths and high rates of ground water velocity, which may not be accurately conceptualized in groundwater flow models. In addition, recent research suggests the presence of numerous vertical dissolution features across Everglades National Park at Long Pine Key Trail, that may act as areas of direct recharge to the aquifer. These vertical features have been identified through ground penetrating radar (GPR) surveys as areas of velocity pull-down which have been modeled to have porosity values higher than the surrounding Miami Limestone. As climate change may induce larger and longer temporal variability between wet and dry times in the Everglades, a more comprehensive understanding of preferential flow pathways from the surface to the aquifer would be a great benefit to modelers and planners. This research utilizes near surface geophysical techniques, such as GPR, to identify these vertical dissolution features and then estimate the spatial variability of porosity using petrophysical models. GPR transects that were collected for several kilometers along the Long Pine Key Trail, show numerous pull down areas that correspond to dissolution enhanced porosity zones within the Miami Limestone. Additional 3D GPR surveys have attempted to delineate the boundaries of these features to elucidate their geometry for future modelling studies. We demonstrate the ability of near surface geophysics and petrophysical models to identify dissolution enhanced porosity in shallow karstic limestones to better understand areas that may act as zones of direct recharge into the Biscayne Aquifer.

Sedimentary and Vegetative Impacts of Hurricane Irma to Coastal Wetland Ecosystems across Southwest Florida

Science.gov (United States)

Moyer, R. P.; Khan, N.; Radabaugh, K.; Engelhart, S. E.; Smoak, J. M.; Horton, B.; Rosenheim, B. E.; Kemp, A.; Chappel, A. R.; Schafer, C.; Jacobs, J. A.; Dontis, E. E.; Lynch, J.; Joyse, K.; Walker, J. S.; Halavik, B. T.; Bownik, M.

2017-12-01

Since 2014, our collaborative group has been working in coastal marshes and mangroves across Southwest Florida, including Tampa Bay, Charlotte Harbor, Ten Thousand Islands, Biscayne Bay, and the lower Florida Keys. All existing field sites were located within 50 km of Hurricane Irma's eye path, with a few sites in the Lower Florida Keys and Naples/Ten Thousand Islands region suffering direct eyewall hits. As a result, we have been conducting storm-impact and damage assessments at these locations with the primary goal of understanding how major hurricanes contribute to and/or modify the sedimentary record of mangroves and salt marshes. We have also assessed changes to the vegetative structure of the mangrove forests at each site. Preliminary findings indicate a reduction in mangrove canopy cover from 70-90% pre-storm, to 30-50% post-Irma, and a reduction in tree height of approximately 1.2 m. Sedimentary deposits consisting of fine carbonate mud up to 12 cm thick were imported into the mangroves of the lower Florida Keys, Biscayne Bay, and the Ten Thousand Islands. Import of siliciclastic mud up to 5 cm thick was observed in Charlotte Harbor. In addition to fine mud, all sites had imported tidal wrack consisting of a mixed seagrass and mangrove leaf litter, with some deposits as thick as 6 cm. In areas with newly opened canopy, a microbial layer was coating the surface of the imported wrack layer. Overwash and shoreline erosion were also documented at two sites in the lower Keys and Biscayne Bay, and will be monitored for change and recovery over the next few years. Because active research was being conducted, a wealth of pre-storm data exists, thus these locations are uniquely positioned to quantify hurricane impacts to the sedimentary record and standing biomass across a wide geographic area. Due to changes in intensity along the storm path, direct comparisons of damage metrics can be made to environmental setting, wind speed, storm surge, and distance to eyewall.

Rhabdosargus holubi Rhabdosargus globiceps

African Journals Online (AJOL)

Bioi. 17: 143-162. CARR, W.E.S. & ADAMS, C.A. 1973. Food habits of juvenile marine fishes occupying seagrass beds in the estuarine zone near. Crystal River, Florida. Trans. A mer. Fish. Soc. 3: 511- 540. CHARLES, R. 1975. Aspects of the biology of the mojarra. Eucinostomus gula (Quoy & Gaimard), in the Biscayne Bay,.

Studies of movement of sediments in Santos bay

International Nuclear Information System (INIS)

Bandeira, J.V.; Aun, P.E.; Bomtempo, V.L.; Salim, L.H.; Minardi, P.S.P.; Santos, J.A.

1990-01-01

In the years of 1973, 74, 80, 81 and 85 several studies were performed at Santos bay, using radioactive tracers, with the following main objectives: to evaluate the behaviour (on the bottom and in suspension) of the mixture of silt and clay which is dredged from the estuary and from its access channel and dumped at pre-determined sites, in the bay and surrounding regions, with the objective of optimizing dredging disposal operations; to quantify the movement of sandy sediments on the bottom, in 3 areas of the bay, in summer and winter conditions, to obtain pertinent information related to the siltation of the access channel. As results of these studies, it was found that: the ancient dumping site, near Itaipu Point, in the western limit of the bay, was inadequate, since the material could return to the bay and to the estuary. The dumping site was moved to a region at the south of Moela Island, located eastwards relative to the bay, which brought substantial economies in dredging works; the bottom sediment transport was quantified, following clouds of tagged materials for about 8 months, thus obtaining important conclusions about transport rates in different regions of the bay. An analysis of the intervening hydrodynamic agents is also presented. (author) (L.J.C.)

Some atmospheric dispersion, wind and temperature statistics from Jervis Bay, Australian Capital Territory 1972 to 1974

International Nuclear Information System (INIS)

Clark, G.H.

1985-07-01

A meteorological study of winds, temperatures and Pasquill stability categories was conducted in the coastal conditions at Jervis Bay. Three Pasquill stability categorisation schemes were compared. These indicated a predominance of neutral to slightly unstable conditions. During the daytime, north bay breezes and north-east sea breezes were most common together with on-shore south-east winds. Off-shore south-west winds prevailed during winter and were observed most frequently at night

Patterns of alien plant invasion across coastal bay areas in southern China

Science.gov (United States)

Hai Ren; Qinfeng Guo; Hong Liu; Jing Li; Qianmei Zhang; Hualin Xu; Fanghong Xu

2014-01-01

An understanding of the ways in which levels of invasions by alien species are correlated with environmental factors is helpful to manage the negative impacts of these invasive species. Two tropical coastal areas in South China, Shenzhen Bay and Leizhou Bay, are national nature reserves, but they are threatened by invasive plants. Here, we investigated the level of...

The effects of coal dust on photosynthetic performance of the mangrove, Avicennia marina in Richards Bay, South Africa

International Nuclear Information System (INIS)

Naidoo, G.; Chirkoot, D.

2004-01-01

Richards Bay, on the northern KwaZulu-Natal coast, is the largest coal exporting port in South Africa. The coal is stored at the Richards Bay Coal Terminal (RBCT) prior to export. Dust from coal operations is a major problem in the Richards Bay area. In this study, we tested the hypothesis that coal dust adversely affects photosynthetic performance of Avicennia marina (Forssk.) Vierh., the dominant mangrove species in the harbour. Photosynthetic performance was determined on 10 trees by measuring carbon dioxide uptake and chlorophyll fluorescence parameters at two elevation sites and on upper and lower leaf surfaces that were covered or uncovered with coal dust. Measurements were made on five clear, sunny days at saturating light (>1000 μmol m -2 s -1 ) and high temperature (28-30 deg. C). Coal dust significantly reduced carbon dioxide exchange of upper and lower leaf surfaces by 17-39%, the reduction being generally greater on the lower leaf surface that is covered by a dense mat of trichomes and salt glands. The reduction in carbon dioxide exchange by coal dust was higher at the high elevation site that supported isolated dwarfed trees. The chlorophyll fluorescence data indicated that leaves coated with dust exhibited significantly lower photosystem II (PS II) quantum yield, lower electron transport rate (ETR) through PSII and reduced quantum efficiency of PSII (F v F m ). The chlorophyll fluorescence data supported the gas exchange measurements and are consistent with reduced photosynthetic performance of leaves coated with coal dust. - Coal dust reduced photosynthetic performance of the mangrove, Avicennia marina

33 CFR 110.156 - Randall Bay, Freeport, Long Island, N.Y.

Science.gov (United States)

2010-07-01

... Island, N.Y. 110.156 Section 110.156 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY ANCHORAGES ANCHORAGE REGULATIONS Anchorage Grounds § 110.156 Randall Bay, Freeport, Long Island, N.Y. (a) The anchorage grounds. Southward of a line 312 feet south of and parallel to the south side...

Environmental management of a highly impacted, urbanized tropical estuary: rehabilitation and restoration

Science.gov (United States)

Thorhaug, A.

1980-03-01

The principles of the dynamics and interrelationships within the dominant subtropical and tropical Caribbean seagrass community have been studied previously before, during, and after impact. From these and scores of observations of damage and recovery patterns in Thalassia ecosystems, a sense of management recovery strategy has emerged. Artificial restoring of Thalassia testudinum seeds into areas cut off from stock (fruit, seeds) appeared feasible on a large scale after the Turkey Point (Biscayne Bay, Miami, Florida) restoration and test sampling throughout North Biscayne Bay. Two large-scale seeding attempts were made; after 11 months they compared favorably with Turkey Point specimens with regard to growth parameters, despite the turbidity and other persistent pollution. Thus, the possible areas in which Thalassia seed restoration can be used has increased to include estuaries of multiple impact still in various stages of recovery after physical and sewage pollution. This technique should be especially useful to “developing” nations where important nearshore fisheries nurseries based on Thalassia ecosystems have been heavily damaged and now lie barren. Man's impact on the estuary where seed restoration was attempted includes the following activities: 50% of the bay bottom directly dredged or filled (leaving much unconsolidated sediment); 50 million gallons of domestic waste dumped directly into a low flushing part of the bay for 20 years; seven major causeways transecting the bay, restricting circulation and flushing; two artificial inlets made into navigational channels; freshwater sheet flow drastically changed due to channelization by flood-control canals; urban runoff from a million people entering the bay. Most of the impacts have now abated; however, their long-term effects remain.

Spatial and temporal trends of contaminants in eggs of wading birds from San Francisco Bay, California

Science.gov (United States)

Hothem, R.L.; Roster, D.L.; King, K.A.; Keldsen, T.J.; Marois, Katherine C.; Wainwright, S.E.

1995-01-01

Between 1989 and 1991, reproduction by black-crowned night-herons (Nycticorax nycticorax) and snowy egrets (Egretta thula) was studied at sites in San Francisco Bay. Eggs were collected from these and other bay sites and from South Wilbur Flood Area, a reference site in California's San Joaquin Valley. Eggs were analyzed for inorganic trace elements, organochlorine pesticides, and polychlorinated biphenyls (PCBs). Results were compared among sites and years and with results of previous studies. There was some evidence of impaired reproduction, but concentrations of contaminants were generally lower than threshold levels for such effects. Egg hatchability was generally good, with predation being the factor that most limited reproductive success. Mean PCB concentrations were generally higher in eggs from the south end of San Francisco Bay than from the north, but the only temporal change, an increase, was observed at Alcatraz Island. There were spatial differences for p,p'-DDE in night-heron eggs in 1990, but the highest mean concentration of DDE was in night-heron eggs from South Wilbur in 1991. Temporal declines in maximum concentrations of DDE in eggs were observed in the bay, but means did not change significantly over time, At Bair Island in the southern end of the bay, mean concentrations of mercury decreased while selenium increased in night-heron eggs over time, but there were no clear bay-wide spatial or temporal trends for either element.

Meteorological, biological, and hydrographic data collected from Middle Bay Lighthouse in Mobile Bay, AL from 05/23/2005 - 12/31/2013 (NODC Accession 0117376)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Abstract: Dauphin Island Sea Lab and the Mobile Bay National Estuary Program have partnered with the University of South Alabama, the Alabama Department of...

Seismic stratigraphy and late Quaternary shelf history, south-central Monterey Bay, California

Science.gov (United States)

Chin, J.L.; Clifton, H.E.; Mullins, H.T.

1988-01-01

The south-central Monterey Bay shelf is a high-energy, wave-dominated, tectonically active coastal region on the central California continental margin. A prominent feature of this shelf is a sediment lobe off the mouth of the Salinas River that has surface expression. High-resolution seismic-reflection profiles reveal that an angular unconformity (Quaternary?) underlies the entire shelf and separates undeformed strata above it from deformed strata below it. The Salinas River lobe is a convex bulge on the shelf covering an area of approximately 72 km2 in water depths from 10 to 90 m. It reaches a maximum thickness of 35 m about 2.5 km seaward of the river mouth and thins in all directions away from this point. Adjacent shelf areas are characterized by only a thin (2 to 5 m thick) and uniform veneer of sediment. Acoustic stratigraphy of the lobe is complex and is characterized by at least three unconformity-bounded depositional sequences. Acoustically, these sequences are relatively well bedded. Acoustic foresets occur within the intermediate sequence and dip seaward at 0.7?? to 2.0??. Comparison with sedimentary sequences in uplifted onshore Pleistocene marine-terrace deposits of the Monterey Bay area, which were presumably formed in a similar setting under similar processes, suggests that a general interpretation can be formulated for seismic stratigraphic patterns. Depositional sequences are interpreted to represent shallowing-upwards progradational sequences of marine to nonmarine coastal deposits formed during interglacial highstands and/or during early stages of falling sea level. Acoustic foresets within the intermediate sequence are evidence of seaward progradation. Acoustic unconformities that separate depositional sequences are interpreted as having formed largely by shoreface planation and may be the only record of the intervening transgressions. The internal stratigraphy of the Salinas River lobe thus suggests that at least several late Quaternary

Pollution of HCHs, DDTs and PCBs in tidal flat of Hangzhou Bay 2009-2013

Science.gov (United States)

Zhao, Peng; Gong, Wenjie; Mao, Guohua; Li, Jige; Xu, Fenfen; Shi, Jiawei

2016-05-01

The concentration and distribution of three persistent organic pollutants (hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethanes (DDTs) and polychlorinated biphenyls (PCBs)) was assessed in tidal flat sediments collected from the south bank of Hangzhou Bay, China from 2009 to 2013. Gas chromatography coupled to triple quadrupole mass spectrometry (GC-MS/MS) was used for analysis, based on United States Environmental Protection Agency methods EPA8080A, EPA8081B, and EPA3550B. The results showed that the levels of HCHs, DDTs and PCBs decreased in the order of DDTs transformer or electronic equipment in the south bank of Hangzhou Bay.

Rapid Crustal Uplift at Birch Bay, Washington

Science.gov (United States)

Sherrod, B. L.; Kelsey, H. M.; Blakely, R. J.

2010-12-01

Geomorphology and coastal marsh stratigraphy suggest late Holocene uplift of the shoreline at Birch Bay, located northwest of Bellingham, Washington, during an earthquake on a shallow fault. LiDAR images show a raised, late Holocene shoreline along Birch Bay, with ~1 m of elevation difference between the modern shoreline and the inferred paleoshoreline. Commercial seismic reflection images reveal an anticline in Tertiary and possibly Quaternary deposits underlying Birch Bay. NW-trending magnetic anomalies are likely associated with the Birch Bay anticline and other nearby structures. Taken together, the geophysical data and lidar images suggest uplift of young deposits along a NW-trending blind reverse fault. Stratigraphy from Terrell Creek marsh, located just south of Birch Bay, shows freshwater peat buried by lower intertidal muds, indicating local submergence ~1300 yr BP. Stratigraphy of a 70-cm sediment core from Birch Bay marsh, sitting astride the anticline imaged with seismic reflection data, shows mud buried by detrital peat. One radiocarbon age from the core places the abrupt change from mud to peat prior to 1520-1700 yr BP. We divide fossil diatom assemblages straddling the mud-peat contact at Birch Bay into three zones. The oldest zone consists primarily of intertidal and marine diatoms, dominated by Paralia sulcata, Scoleoneis tumida, Grammataphora oceanica, and Gyrosigma balticum. An intermediate zone, beginning at the sharp contact between mud and overlying peat, consists of a mixture of brackish marsh and freshwater species, dominated by Diploneis interrupta, with lesser amounts of Aulacoseira sp., Pinnularia viridis, Eunotia pectinalis, and Paralia sulcata. A third and youngest zone lies in the upper half of the peat and is dominated by poorly preserved freshwater diatoms, mostly Aulacoseira cf. crassapuntata, Pinnularia viridis, P. maior, Eunotia pectinalis, and E. praerupta. Paleoecological inferences, based on distributions of modern diatoms

Temporal and spatial distribution of the meiobenthic community in Daya Bay, South China Sea

Science.gov (United States)

Tang, L.; Li, H. X.; Yan, Y.

2012-04-01

Spatial and temporal biodiversity patterns of the meiobenthos were studied for the first time in Daya Bay, which is a tropical semi-enclosed basin located in the South China Sea. The abundance, biomass, and composition of the meiobenthos and the basic environmental factors in the bay were investigated. The following 19 taxonomic groups were represented in the meiofauna: Nematoda, Copepoda, Polychaeta, Oligochaeta, Kinorhyncha, Gastrotricha, Ostracoda, Bivalvia, Turbellaria, Nemertinea, Sipuncula, Hydroida, Amphipoda, Cumacea, Halacaroidea, Priapulida, Echinodermata, Tanaidacea, and Rotifera. Total abundance and biomass of the meiobenthos showed great spatial and temporal variation, with mean values of 993.57 ± 455.36 ind cm-2 and 690.51 ± 210.64 μg 10 cm-2, respectively. Nematodes constituted 95.60 % of the total abundance and thus had the greatest effect on meiofauna quantity and distribution, followed by copepods (1.55 %) and polychaetes (1.39 %). Meiobenthos abundance was significantly negatively correlated with water depth at stations (r=-0.747, P<0.05) and significantly negatively correlated with silt-clay content (r=-0.516, P<0.01) and medium diameter (r=-0.499, P<0.01) of the sediment. Similar results were found for correlations of biomass and abundance of nematodes with environmental parameters. Polychaete abundance was positively correlated with the bottom water temperature (r=0.456, P<0.01). Meiobenthos abundance differed significantly among seasons (P<0.05), although no significant difference among stations and the interaction of station × season was detected by two-way ANOVA. In terms of vertical distribution, most of the meiobenthos was found in the surface layer of sediment. This pattern was apparent for nematodes and copepods, but a vertical distribution pattern for polychaetes was not as obvious. Based on the biotic indices and analyses of their correlations and variance, the diversity of this community was likely to be influenced by

Phytoplankton and nutrient dynamics in Winyah Bay, SC.

Science.gov (United States)

Boneillo, G. E.; Brooks, S. S.; Brown, S. L.; Woodford, K. M.; Wright, C. R.

2016-02-01

Winyah Bay is a coastal plain estuary located in South Carolina that has been classified for a moderate risk of Eutrophication by NOAA. Winyah Bay receives freshwater input from four rivers, the Waccamaw, Sampit, Black, and Pee Dee Rivers. The Waccamaw, Sampit and Black River are blackwater systems that discharge elevated amounts of colored dissolved organic matter. During the summer and fall of 2015, bioassay experiments were performed to simultaneously examine both light and nutrient (nitrogen & phosphate) limitation throughout Winyah Bay. Sampling stations near the mouth of the Waccamaw and Sampit Rivers showed that phytoplankton were light limited in the late summer instead of nutrient limited. These stations were located in the industrialized area of the bay and typically had the highest nutrient concentrations and highest turbidity, with Secchi depths typically less than 0.5 meters. Results indicated that phytoplankton may be nitrogen limited near the mouth of Winyah Bay, where nutrient concentrations and turbidity were observed to be lower than locations further upstream. There was also an observed dissolved oxygen and pH gradient during the summer of 2015. Dissolved oxygen levels less than 4.0 mg/L were routinely observed near the industrialized head of the estuary and corresponded with lower pH values.

A Case History of the Science and Management Collaboration in Understanding Hypoxia Events in Long Bay, South Carolina, USA

Science.gov (United States)

Sanger, Denise; Hernandez, Debra; Libes, Susan; Voulgaris, George; Davis, Braxton; Smith, Erik; Shuford, Rebecca; Porter, Dwayne; Koepfler, Eric; Bennett, Joseph

2010-09-01

Communication of knowledge between the scientific and management communities is a difficult process complicated by the distinctive nature of professional career goals of scientists and decision-makers. This article provides a case history highlighting a collaboration between the science and management communities that resulted from a response to a 2004 hypoxia, or low dissolved oxygen, event in Long Bay, off Myrtle Beach, South Carolina. A working group of scientists and decision-makers was established at the time of the event and has continued to interact to develop a firm understanding of the drivers responsible for hypoxia formation in Long Bay. Several factors were found to be important to ensure that these collaborative efforts were productive: (1) genuine interest in collaboratively working across disciplines to examine a problem; (2) commitment by agency leadership, decision-makers, and researchers to create successful communication mechanisms; (3) respect for each others’ perspectives and an understanding how science and management are performed and that they are not mutually exclusive; (4) networking among researchers and decision-makers to ensure appropriate team members are involved in the process; (5) use of decision-maker input in the formulation of research and monitoring projects; and (6) commitment of resources for facilitation to ensure that researchers and decision-makers are communicating effectively.

A LEOPARD SEAL FROM HOUT BAY, SOUTH AFRICA Division of ...

African Journals Online (AJOL)

On 14 October 1969 a leopard seal Hydrurga leptonyx came ashore alive at Hout Bay, Cape. Province .... 5 mm in diameter: on histological examination these proved to be small nematodes Para- filaroides sp. ... Seals, sea lions and walruses.

Particulate carbohydrate in the euphotic zone of the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Bhosle, N; De; Shirodkar, P.V.; Reddy, C.V.G.

Particulate matter collected from the Bay of Bengal was analysed for carbohydrate and chlorophyll a. The distribution of chlorophyll a was different from that of carbohydrate. Chlorophyll a increased from north to south, whereas carbohydrate levels...

Ferric Iron Precipitation in the Nagahama Bay, Satsuma Iwo-Jima Island, Kagoshima

Science.gov (United States)

Nagata, T.; Kiyokawa, S.; Ikehara, M.; Oguri, K.; Goto, S.; Ito, T.; Yamaguchi, K. E.; Ueshiba, T.

2010-12-01

Satsuma-Iwojima island is active volcanic island and 6 x 3 km in size, located 38km south of Kyushu island, Japan. The reddish brown water along the coast of the Iwo-dake volcano at the center of the island formed by neutralization through mixing of shallow hydrothermal fluid and seawater. The reddish brown water contains reddish ferrihydrite (Fe3+) that is derived from oxidation of Fe2+ from acidic hot spring (Shikaura and Tazaki, 2001). In the Nagahama Bay with its opening to the south, red-colored Fe-rich water is affected by tidal current, but sedimentation of the ferric hydroxide is confirmed to occur in the ocean bottom (Ninomiya and Kiyokawa, 2009). Here we focus other lines of evidence from long term observations and meteorological records as important factor to form thick iron rich sediments. Meteorological and stationary observations: We used weather record in the Satsuma Iwo-jima and cross-checked with stationary observations, which enabled us to observe color changes of the surface of Nagahama Bay. It was made clear that north wind condition in the Nagahama Bay resulted in changes of the color of its surface, from red to green, by intrusion of ocean water coming from outside. Long term temperature monitoring: The temperature of seawater in the Nagahama Bay fluctuated synchronically with the air temperature. But that of hot spring water rather remained constant regardless of the seasonal change. We observed that seawater temperature in the Nagahama Bay is low at high tide and high at low tide, and the rage of temperature change is maximum at the spring tide and minimum at the neap tide. In other words, the amount of discharge of hot spring and that of seawater inflow vary inversely. Core sample: In the Nagahama Bay, iron rich sediments that is more than 1 m thick were identified. The core sample shows lithology as following; upper part, 10-20cm thick, formed loose Fe-rich deposit, lower portion formed alteration of weakly consolidated Fe-rich orange

Case Study: The Myanmar and Bangladesh Maritime Boundary Dispute in the Bay of Bengal and Its Implications for South China Sea Claims

Directory of Open Access Journals (Sweden)

Ravi A. Balaram

2012-01-01

Full Text Available This paper seeks to review the pertinent Myanmar and Bangladesh history in overlapping maritime territorial claims leading up to the September 2011 International Tribunal for the Law of the Sea (ITLOS case: Dispute Concerning Delimitation of the Maritime Boundary Between Bangladesh and Myanmar in the Bay of Bengal. It will dissect the legal proceedings as primary source documents and apply the relevant judgement findings to analyse the implications for the respective countries and for South China Sea maritime boundary disputes. While the judgements of this case set certain legal precedents that may be more easily applied to bilateral disputes, the implications, nevertheless, impinge on multilateral claims as well. To the extent that the Bangladesh-Myanmar ITLOS judgement provides a pathway to third-party, independent, and peaceful resolution to the potentially explosive and escalating tensions in the South China Sea, this paper argues that findings are relevant, but limited.

Summer at the beach: spatio-temporal patterns of white shark occurrence along the inshore areas of False Bay, South Africa.

Science.gov (United States)

Kock, Alison A; Photopoulou, Theoni; Durbach, Ian; Mauff, Katya; Meÿer, Michael; Kotze, Deon; Griffiths, Charles L; O'Riain, M Justin

2018-01-01

Understanding white shark ( Carcharodon carcharias ) habitat use in coastal areas adjacent to large cities, is an important step when formulating potential solutions to the conservation conflict that exists between humans and large predatory sharks. In this study, we present the findings of a 2.5-year study of white shark occurrence and movement patterns adjacent to the City of Cape Town in False Bay, South Africa, with a focus on spring and summer months. Fifty-one white sharks were monitored annually at three offshore and twelve inshore sites by VR2 acoustic receivers, over 975 days from 1 May 2005 to 31 December 2007. Occurrence patterns at inshore sites during spring and summer were analysed using a generalized additive mixed model (GAMM) with a spatial term (longitude, latitude), time of day and year included as explanatory variables for site use. We found that sharks occurred more frequently at inshore sites along the northern and northwestern shores, compared to the rest of the bay, and they transitioned most frequently between four adjacent beach sites that encompass the most popular recreational water use areas in Cape Town. There was significant diel variation, with higher shark occurrence around midday, and a peak in shark occurrence in 2005, when human-shark interactions also peaked. However, we found no effect of shark size on occurrence patterns at inshore sites. White sharks showed the highest levels of occurrence at specific inshore sites between Muizenberg and Strandfontein beach, and thus inclusion of these sites within False Bay's marine protected area (MPA) network or recognition as Ecological or Biological Significant Areas (EBSAs) should be a future consideration. These insights into white shark habitat use at inshore sites in False Bay are important for successfully applying the principles of marine spatial planning (MSP) and for making science-based policy decisions. Furthermore, this information can be used to reduce potential shark

Spatial variation of phytoplankton community structure in Daya Bay, China.

Science.gov (United States)

Jiang, Zhao-Yu; Wang, You-Shao; Cheng, Hao; Zhang, Jian-Dong; Fei, Jiao

2015-10-01

Daya Bay is one of the largest and most important gulfs in the southern coast of China, in the northern part of the South China Sea. The phylogenetic diversity and spatial distribution of phytoplankton from the Daya Bay surface water and the relationship with the in situ water environment were investigated by the clone library of the large subunit of ribulose-1, 5-bisphosphate carboxylase (rbcL) gene. The dominant species of phytoplankton were diatoms and eustigmatophytes, which accounted for 81.9 % of all the clones of the rbcL genes. Prymnesiophytes were widely spread and wide varieties lived in Daya Bay, whereas the quantity was limited. The community structure of phytoplankton was shaped by pH and salinity and the concentration of silicate, phosphorus and nitrite. The phytoplankton biomass was significantly positively affected by phosphorus and nitrite but negatively by salinity and pH. Therefore, the phytoplankton distribution and biomass from Daya Bay were doubly affected by anthropic activities and natural factors.

An aerial radiological survey of the South Texas Project Electric Generating Station and surrounding area, Bay City, Texas

International Nuclear Information System (INIS)

Thompson, J.M.

1988-12-01

An aerial radiological survey was conducted over the South Texas Project Electric Generating Station (STPEGS) near Bay City, Texas, during the period 25 March to 4 April 1988. The purpose of the 259-square-kilometer (100-square-mile) survey was to document the terrestrial gamma environment of the plant and surrounding area. An exposure rate contour map at 1 meter above ground level (AGL) was constructed from the gamma data and overlaid on an aerial photograph and map of the area. Exposure rates were observed up to 10μR/h over land. No areas of enhanced exposure rates were observed. Ground-based exposure rate measurements and soil samples were obtained to support the aerial data. Oblique aerial photographs of the plant were also acquired during the survey. 9 refs., 4 figs., 1 tab

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. 

Tumor prevalence and biomarkers of genotoxicity in brown bullhead (Ameiurus nebulosus) in Chesapeake Bay tributaries

Energy Technology Data Exchange (ETDEWEB)

Pinkney, Alfred E., E-mail: Fred_Pinkney@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Harshbarger, John C., E-mail: jcharshbarger@verizon.net [Department of Pathology, George Washington University Medical Center, 2300 I Street, NW, Washington, DC 20037 (United States); Karouna-Renier, Natalie K., E-mail: nkarouna@usgs.gov [U.S. Geological Survey, Patuxent Wildlife Research Center, BARC, Bldg. 308, Beltsville, MD 20705 (United States); Jenko, Kathryn [U.S. Geological Survey, Patuxent Wildlife Research Center, BARC, Bldg. 308, Beltsville, MD 20705 (United States); Balk, Lennart, E-mail: lennart.balk@itm.su.se [Department of Applied Environmental Science (ITM), Stockholm University SE-106 91, Stockholm (Sweden); Skarphe Latin-Small-Letter-Eth insdottir, Halldora; Liewenborg, Birgitta [Department of Applied Environmental Science (ITM), Stockholm University SE-106 91, Stockholm (Sweden); Rutter, Michael A., E-mail: mar36@psu.edu [Department of Mathematics, Penn State Erie, The Behrend College, 5091 Station Road, Erie, PA 16563 (United States)

2011-12-01

We surveyed four Chesapeake Bay tributaries for skin and liver tumors in brown bullhead (Ameiurus nebulosus). We focused on the South River, where the highest skin tumor prevalence (53%) in the Bay watershed had been reported. The objectives were to 1) compare tumor prevalence with nearby rivers (Severn and Rhode) and a more remote river (Choptank); 2) investigate associations between tumor prevalence and polynuclear aromatic hydrocarbons (PAHs) and alkylating agents; and 3) statistically analyze Chesapeake Bay bullhead tumor data from 1992 through 2008. All four South River collections exhibited high skin tumor prevalence (19% to 58%), whereas skin tumor prevalence was 2%, 10%, and 52% in the three Severn collections; 0% and 2% in the Choptank collections; and 5.6% in the Rhode collection. Liver tumor prevalence was 0% to 6% in all but one South River collection (20%) and 0% to 6% in the three other rivers. In a subset of samples, PAH-like biliary metabolites and {sup 32}P-DNA adducts were used as biomarkers of exposure and response to polycyclic aromatic compounds (PACs). Adducts from alkylating agents were detected as O6-methyl-2 Prime -deoxyguanosine (O6Me-dG) and O6-ethyl-2 Prime -deoxyguanosine (O6Et-dG) modified DNA. Bullheads from the contaminated Anacostia River were used as a positive control for DNA adducts. {sup 32}P-DNA adduct concentrations were significantly higher in Anacostia bullhead livers compared with the other rivers. We identified alkyl DNA adducts in bullhead livers from the South and Anacostia, but not the Choptank. Neither the PAH-like bile metabolite data, sediment PAH data, nor the DNA adduct data suggest an association between liver or skin tumor prevalence and exposure to PACs or alkylating agents in the South, Choptank, Severn, or Rhode rivers. Logistic regression analysis of the Chesapeake Bay database revealed that sex and length were significant covariates for liver tumors and length was a significant covariate for skin tumors

Tumor prevalence and biomarkers of genotoxicity in brown bullhead (Ameiurus nebulosus) in Chesapeake Bay tributaries

International Nuclear Information System (INIS)

Pinkney, Alfred E.; Harshbarger, John C.; Karouna-Renier, Natalie K.; Jenko, Kathryn; Balk, Lennart; Skarphéðinsdóttir, Halldóra; Liewenborg, Birgitta; Rutter, Michael A.

2011-01-01

We surveyed four Chesapeake Bay tributaries for skin and liver tumors in brown bullhead (Ameiurus nebulosus). We focused on the South River, where the highest skin tumor prevalence (53%) in the Bay watershed had been reported. The objectives were to 1) compare tumor prevalence with nearby rivers (Severn and Rhode) and a more remote river (Choptank); 2) investigate associations between tumor prevalence and polynuclear aromatic hydrocarbons (PAHs) and alkylating agents; and 3) statistically analyze Chesapeake Bay bullhead tumor data from 1992 through 2008. All four South River collections exhibited high skin tumor prevalence (19% to 58%), whereas skin tumor prevalence was 2%, 10%, and 52% in the three Severn collections; 0% and 2% in the Choptank collections; and 5.6% in the Rhode collection. Liver tumor prevalence was 0% to 6% in all but one South River collection (20%) and 0% to 6% in the three other rivers. In a subset of samples, PAH-like biliary metabolites and 32 P-DNA adducts were used as biomarkers of exposure and response to polycyclic aromatic compounds (PACs). Adducts from alkylating agents were detected as O6-methyl-2′-deoxyguanosine (O6Me-dG) and O6-ethyl-2′-deoxyguanosine (O6Et-dG) modified DNA. Bullheads from the contaminated Anacostia River were used as a positive control for DNA adducts. 32 P-DNA adduct concentrations were significantly higher in Anacostia bullhead livers compared with the other rivers. We identified alkyl DNA adducts in bullhead livers from the South and Anacostia, but not the Choptank. Neither the PAH-like bile metabolite data, sediment PAH data, nor the DNA adduct data suggest an association between liver or skin tumor prevalence and exposure to PACs or alkylating agents in the South, Choptank, Severn, or Rhode rivers. Logistic regression analysis of the Chesapeake Bay database revealed that sex and length were significant covariates for liver tumors and length was a significant covariate for skin tumors. - Highlights: ► We

A new ceramic assemblage from Caution Bay, south coast of mainland PNG : the linear shell edge-impressed tradition from Bogi 1

International Nuclear Information System (INIS)

David, B.; McNiven, I.J.; Leavesley, M.; Barker, B.; Mandui, H.; Richards, T.; Skelly, R.

2012-01-01

This paper reports on the ceramics from Squares A and B of Bogi 1, a newly excavated site at Caution Bay, south coast of mainland Papua New Guinea. A dense cultural horizon dated from c. 2150 to c. 2100 calBP and preceded by earlier cultural deposits contains previously undescribed ceramics of limited decorative variability almost exclusively focused on Anadara shell edge impressions below finger-grooved lips, which we term the Linear Shell Edge-Impressed Tradition. Here we present the chrono-stratigraphic evidence for this decorative tradition and how it relates to previously described shell-impressed ceramics from the broader region. (author). 16 refs., 9 figs., 3 tabs.

Travel to Food : Transportation Barriers for the Food Insecure in Tampa Bay

Science.gov (United States)

2017-09-01

In partnership with the Center for Urban Transportation Research (CUTR) at the University of South Florida (USF), the Transportation Innovation Group informed practical transportation solutions aimed at improved food access in Tampa Bay (Hillsborough...

Antibiotics in the coastal environment of the Hailing Bay region, South China Sea: Spatial distribution, source analysis and ecological risks.

Science.gov (United States)

Chen, Hui; Liu, Shan; Xu, Xiang-Rong; Zhou, Guang-Jie; Liu, Shuang-Shuang; Yue, Wei-Zhong; Sun, Kai-Feng; Ying, Guang-Guo

2015-06-15

In this study, the occurrence and spatial distribution of 38 antibiotics in surface water and sediment samples of the Hailing Bay region, South China Sea, were investigated. Twenty-one, 16 and 15 of 38 antibiotics were detected with the concentrations ranging from antibiotics in the water phase were correlated positively with chemical oxygen demand and nitrate. The source analysis indicated that untreated domestic sewage was the primary source of antibiotics in the study region. Fluoroquinolones showed strong sorption capacity onto sediments due to their high pseudo-partitioning coefficients. Risk assessment indicated that oxytetracycline, norfloxacin and erythromycin-H2O posed high risks to aquatic organisms. Copyright © 2015 Elsevier Ltd. All rights reserved.

Apostle Battery Table Bay Fire Command | Croock | Scientia Militaria ...

African Journals Online (AJOL)

Scientia Militaria: South African Journal of Military Studies. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 20, No 3 (1990) >. Log in or Register to get access to full text downloads. Username, Password, Remember me, or Register. Apostle Battery Table Bay Fire ...

Parameterization of surface irradiance and primary production in Århus Bay, SW Kattegat, Baltic Sea

DEFF Research Database (Denmark)

Lund-Hansen, Lars Chresten; Sørensen, Helene Munk

2009-01-01

. The study is based on a one year long time-series of PAR, CTD-casts (n = 45), and primary production measurements (n = 24) from Århus Bay (56°09′ N; 10°20′ E), south west Kattegat. Results showed a high and positive correlation between observed and calculated primary production in the bay, as based...

Descriptions and preliminary report on sediment cores from the southwest coastal area, Everglades National Park, Florida

Science.gov (United States)

Wingard, G. Lynn; Cronin, Thomas M.; Holmes, Charles W.; Willard, Debra A.; Budet, Carlos A.; Ortiz, Ruth E.

2005-01-01

Sediment cores were collected from five locations in the southwest coastal area of Everglades National Park, Florida, in May 2004 for the purpose of determining the ecosystem history of the area and the impacts of changes in flow through the Shark River Slough. An understanding of natural cycles of change prior to significant human disturbance allows land managers to set realistic performance measures and targets for salinity and other water quality and quantity quality measures. Preliminary examination of the cores indicates significant changes have taken place over the last 1000-2000 years. The cores collected from the inner bays - the most landward bays - are distinctly different from other estuarine sediment cores examined in Florida Bay and Biscayne Bay. Peats in the inner-bay cores from Big Lostmans Bay, Broad River Bay, and Tarpon Bay were deposited at least 1000 years before present (BP) based on radiocarbon analyses. The peats are overlain by poorly sorted organic muds and sands containing species indicative of deposition in a freshwater to very low salinity environment. The Alligator Bay core, the most northern inner-bay core, is almost entirely sand; no detailed faunal analyses or radiometric dating has been completed on this core. The Roberts River core, taken from the mouth of the River where it empties into Whitewater Bay, is lithologically and faunally similar to previously examined cores from Biscayne and Florida Bays; however, the basal unit was deposited ~2000 years before the present based on radiocarbon analyses. A definite trend of increasing salinity over time is seen in the Roberts River core, from sediments representing a terrestrially dominated freshwater environment at the bottom of the core to those representing an estuarine environment with a strong freshwater influence at the top. The changes seen at Roberts River could represent a combination of factors including rising sea-level and changes in freshwater supply, but the timing and

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

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

Tectonic framework of the Hanoe Bay area, southern Baltic Sea

International Nuclear Information System (INIS)

Wannaes, K.O.; Floden, T.

1994-06-01

The tectonic framework and the general geologic development of the Hanoe Bay, from the Scanian coast in the west to south of Oeland in the east, has been investigated by means of reflection seismic methods. The Hanoe Bay is in this paper subdivided into four areas of different geologic settings. These are: 1) The Hanoe Bay slope, which forms a southward dipping continuation of the rigid Blekinge coastal plain. 2) The eastward dipping Kalmarsund Slope, which southwards from Oeland forms the western part of the Paleozoic Baltic Syneclise. 3) The Mesozoic Hanoe Bay Halfgraben, which forms the central and southern parts of the Hanoe Bay. The ongoing subsidence of the Halfgraben is estimated to be in the order of 20-60 m during the Quaternary. 4) The Yoldia Structural Element, which forms a deformed, tilted and possibly rotated block of Paleozoic bedrock located east of the Hanoe Bay Halfgraben. Two tectonic phases dominate the post-Paleozoic development of the Hanoe Bay, these are: 1) The Early Kimmerian phase, which initiated subsidence and reactivated older faults. 2) The Late Cretaceous phase, which is the main subsidence phase of the Hanoe Bay Halfgraben. The tectonic fault pattern of the Hanoe Bay is dominated by three directions, i.e. NW-SE, NE-SW and WNW-ESE. The two main tectonic elements of the area are the Kullen-Christiansoe Ridge System (NW-SE) and the Bornholm Gat Tectonic Zone (NE-SW). Sinistral strike-slip movements in order of 2-3 km are interpreted to have occurred along the Bornholm Gat Tectonic Zone during the late Cretaceous. 20 refs, 19 figs

33 CFR 110.95 - Newport Bay Harbor, Calif.

Science.gov (United States)

2010-07-01

... 268° from Lido Isle East Light 2, this line being the northwest line of the main fairway; west of the... of a line bearing 268° from Newport Bay Channel Light 11, this line being the south line of the main... Channel Light 11, this line being the southerly line of the main fairway. Note: This area is reserved for...

Storm-induced inner-continental shelf circulation and sediment transport: Long Bay, South Carolina

Science.gov (United States)

Warner, John C.; Armstrong, Brandy N.; Sylvester, Charlene S.; Voulgaris, George; Nelson, Tim; Schwab, William C.; Denny, Jane F.

2012-01-01

Long Bay is a sediment-starved, arcuate embayment located along the US East Coast connecting both South and North Carolina. In this region the rates and pathways of sediment transport are important because they determine the availability of sediments for beach nourishment, seafloor habitat, and navigation. The impact of storms on sediment transport magnitude and direction were investigated during the period October 2003–April 2004 using bottom mounted flow meters, acoustic backscatter sensors and rotary sonars deployed at eight sites offshore of Myrtle Beach, SC, to measure currents, water levels, surface waves, salinity, temperature, suspended sediment concentrations, and bedform morphology. Measurements identify that sediment mobility is caused by waves and wind driven currents from three predominant types of storm patterns that pass through this region: (1) cold fronts, (2) warm fronts and (3) low-pressure storms. The passage of a cold front is accompanied by a rapid change in wind direction from primarily northeastward to southwestward. The passage of a warm front is accompanied by an opposite change in wind direction from mainly southwestward to northeastward. Low-pressure systems passing offshore are accompanied by a change in wind direction from southwestward to southeastward as the offshore storm moves from south to north.During the passage of cold fronts more sediment is transported when winds are northeastward and directed onshore than when the winds are directed offshore, creating a net sediment flux to the north–east. Likewise, even though the warm front has an opposite wind pattern, net sediment flux is typically to the north–east due to the larger fetch when the winds are northeastward and directed onshore. During the passage of low-pressure systems strong winds, waves, and currents to the south are sustained creating a net sediment flux southwestward. During the 3-month deployment a total of 8 cold fronts, 10 warm fronts, and 10 low

AoA Region: South Asian Seas

Digital Repository Service at National Institute of Oceanography (India)

Naqvi, S.W.A.

is an environmental assessment for the entire Bay of Bengal region (BOBP/ REP/67) prepared for the Swedish Centre for Coastal Development and Management of Aquatic Resources by Holmgren (1994) under the Bay of Bengal Programme. This assessment provides information...-based activities (UNEP 2001) includes information on the South Asian Seas region. Under the Environment Management-Capacity Building Project implemented by the Indian Ministry of Environment and Forests with funding support from the World Bank, the Integrated...

Relationships between precipitation and surface water chemistry in three Carolina bays

International Nuclear Information System (INIS)

Monegue, R.L.; Jagoe, C.H.

1995-01-01

Carolina Bays are shallow freshwater wetlands, the only naturally occurring lentic systems on the southeastern coastal plain. Bays are breeding sites for many amphibian species, but data on precipitation/surface water relationships and long-term chemical trends are lacking. Such data are essential to interpret major fluctuations in amphibian populations. Surface water and bulk precipitation were sampled bi-weekly for over two years at three bays along a 25 km transect on the Savannah River Site in South Carolina. Precipitation chemistry was similar at all sites; average pH was 4.56, and the major ions were H + (30.8 % of total), and SO 4 (50.3% of total). H + was positively correlated with SO 4 , suggesting the importance of anthropogenic acids to precipitation chemistry. All three bays, Rainbow Bay (RB), Thunder Bay (TB), and Ellenton Bay (EB), contained soft (specific conductivity 5--90 microS/cm), acidic water (pH 4.0--5.9) with DOM from 4--40 mg/L. The major cation for RB, TB, and EB, respectively, was: Mg (30.8 % of total); Na (27% of total); and Ca (34.2% of total). DOM was the major anion for all bays, and SO 4 represented 13 to 28 % of total anions. H + was not correlated to DOM or SO, in RB; H + was positively correlated to DOM and SO 4 in TB, and negatively correlated to DOM and SO 4 in EB. Different biogeochemical processes probably control pH and other chemical variables in each bay. While surface water H + was not directly correlated with precipitation H + , NO 3 , or SO 4 , precipitation and shallow groundwater are dominant water sources for these bays. Atmospheric inputs of anthropogenic acids and other chemicals are important factors influencing bay chemistry

Appearance and water quality of turbidity plumes produced by dredging in Tampa Bay, Florida

Science.gov (United States)

Goodwin, Carl R.; Michaelis, D.M.

1984-01-01

near the mouth of Tampa Bay produced a two-part or separated plume. Flow acceleration contracted the width of the visible plume, and subsequent flow deceleration caused plume expansion. The two wide segments of the plume appeared to be separated from each other because of the intervening narrow part. Waters ambient to the plumes were tested for clarity in two sections of Tampa Bay. Ambient-water transparency in Tampa Bay was about three times greater near its mouth, in South Tampa Bay, than near its head, in Hillsborough Bay. Two other measures of water clarity, turbidity and suspended solids, showed no statistically significant difference between the two areas, however, indicating that transparency is a more sensitive measure of ambient water clarity than either turbidity or suspended solids. The nutrient and metal concentrations for samples of plume water and water ambient to the plumes in Tampa Bay were statistically equivalent, indicating no detectable changes due to dredging. The concentrations of dissolved copper, lead, mercury, and total mercury, however, were greater in plumes in Hillsborough Bay than in South Tampa Bay. In Hillsborough Bay, six occurrences of the herbicide 2,4-D at concentrations near the detection limit, 0.01 to 0.05 micrograms per liter, were unrelated to dredging activity. Data recorded for longer than the study period indicate that from 1976 through 1979 few average turbidity characteristics in South Tampa and Hillsborough Bays can be directly attributed to dredging operation

Influence of net freshwater supply on salinity in Florida Bay

Science.gov (United States)

Nuttle, William K.; Fourqurean, James W.; Cosby, Bernard J.; Zieman, Joseph C.; Robblee, Michael B.

2000-01-01

An annual water budget for Florida Bay, the large, seasonally hypersaline estuary in the Everglades National Park, was constructed using physically based models and long‐term (31 years) data on salinity, hydrology, and climate. Effects of seasonal and interannual variations of the net freshwater supply (runoff plus rainfall minus evaporation) on salinity variation within the bay were also examined. Particular attention was paid to the effects of runoff, which are the focus of ambitious plans to restore and conserve the Florida Bay ecosystem. From 1965 to 1995 the annual runoff from the Everglades into the bay was less than one tenth of the annual direct rainfall onto the bay, while estimated annual evaporation slightly exceeded annual rainfall. The average net freshwater supply to the bay over a year was thus approximately zero, and interannual variations in salinity appeared to be affected primarily by interannual fluctuations in rainfall. At the annual scale, runoff apparently had little effect on the bay as a whole during this period. On a seasonal basis, variations in rainfall, evaporation, and runoff were not in phase, and the net freshwater supply to the bay varied between positive and negative values, contributing to a strong seasonal pattern in salinity, especially in regions of the bay relatively isolated from exchanges with the Gulf of Mexico and Atlantic Ocean. Changes in runoff could have a greater effect on salinity in the bay if the seasonal patterns of rainfall and evaporation and the timing of the runoff are considered. One model was also used to simulate spatial and temporal patterns of salinity responses expected to result from changes in net freshwater supply. Simulations in which runoff was increased by a factor of 2 (but with no change in spatial pattern) indicated that increased runoff will lower salinity values in eastern Florida Bay, increase the variability of salinity in the South Region, but have little effect on salinity in the Central

Observations on inshore and pelagic Dolphins on the South-Eastern Cape coast of South Africa

Directory of Open Access Journals (Sweden)

G. S Saayman

1972-12-01

Full Text Available The occurrence, size and seaward distribution of schools of inshore and pelagic dolphins is described for three study areas on the south-eastern Cape coast (Algoa Bay; the Tsitsikama Coastal National Park and Plettenberg Bay. Inshore dolphins {Tursiops and Sousa sp. frequented the coastline in relatively small schools whereas pelagic dolphins {Delphinus delphis and Stenella caeruleoalba occurred in very large schools far out to sea. Different ecological zones were used by Sousa for feeding and for social behaviour and maintenance activities. The frequency of occurrence of Sousa at Plettenberg Bay was not affected by seasonal fluctuations in sea surface temperatures. The role of dolphins as predators and their implication in the regulation of the ecosystem of the Tsitsikama Coastal National Park is discussed.

Mixed layer variability and chlorophyll a biomass in the Bay of Bengal.

Digital Repository Service at National Institute of Oceanography (India)

Narvekar, J.; PrasannaKumar, S.

, the chlorophyll biomass decreases rapidly due to reduction in sunlight by suspended sediment. In the south, advection of high salinity waters from the Arabian Sea and westward propagating Rossby waves from the eastern Bay of Bengal led to the formation of deep...

2011 Tohoku Tsunami Runup Distribution and Damages around Yamada Bay, Iwate

Science.gov (United States)

Okayasu, A.; Shimozono, T.; Sato, S.; Tajima, Y.; Liu, H.; Takagawa, T.; Fritz, H. M.

2011-12-01

On 11 March 2011, a magnitude Mw = 9.0 earthquake occurred off the coast of Japan's Tohoku region causing catastrophic damage and loss of life. A month later, distribution of inundation and run-up height for the tsunami was measured in and outside Yamada Bay locating at the middle of Iwate Prefecture. Yamada Bay has a narrow bay-mouth the width of which is approximately 1/4 of the bay width. The bay is surrounded by two peninsulas, Omoe and Funakoshi Peninsulas and locates in the rear of Funakoshi Peninsula for the epicenter. At eastern side of Omoe Peninsula which is exposed to the Pacific Ocean, the average tsunami height was 15 to 20m at the coast line. All villages there had very large run-up heights of more than 25m and houses at lower elevation were almost completely washed away. The highest run-up, around 40m with an inundation distance of 500 m, was measured at Aneyoshi Village. The village locates at the bottom of a small V-shape inlet which concentrates the energy of tsunamis and amplifies their height. Fortunately, the village itself had been moved to higher ground after severe damages brought by Meiji Sanriku (1896) and Showa Sanriku (1933) Tsunamis and had no loss of life by the 2011 Tsunami. At Funakoshi Peninsula, the south east side of which is facing to the epicenter, the average height of incoming tsunami was estimated to be about 15m. On the contrary, tsunami height inside Yamada Bay was much smaller, generally around 6 to 9m. The only exception was the base of Funakoshi Peninsula where tsunami coming from the other side came over the base of Peninsula and caused devastating damage to the area. The exposed areas south of Funakoshi Peninsula like Kirikiri had tsunami run-up of more than 15m. It is considered that the narrow bay-mouth reduced the tsunami height and Funakoshi Peninsula worked as a barrier for Yamada Bay. Yamada Town locating inside Yamada Bay however suffered a large loss of life. The ratio of dead or missing to its population is

Lattice Boltzmann methods applied to large-scale three-dimensional virtual cores constructed from digital optical borehole images of the karst carbonate Biscayne aquifer in southeastern Florida

Science.gov (United States)

Sukop, Michael C.; Cunningham, Kevin J.

2014-11-01

Digital optical borehole images at approximately 2 mm vertical resolution and borehole caliper data were used to create three-dimensional renderings of the distribution of (1) matrix porosity and (2) vuggy megaporosity for the karst carbonate Biscayne aquifer in southeastern Florida. The renderings based on the borehole data were used as input into Lattice Boltzmann methods to obtain intrinsic permeability estimates for this extremely transmissive aquifer, where traditional aquifer test methods may fail due to very small drawdowns and non-Darcian flow that can reduce apparent hydraulic conductivity. Variogram analysis of the borehole data suggests a nearly isotropic rock structure at lag lengths up to the nominal borehole diameter. A strong correlation between the diameter of the borehole and the presence of vuggy megaporosity in the data set led to a bias in the variogram where the computed horizontal spatial autocorrelation is strong at lag distances greater than the nominal borehole size. Lattice Boltzmann simulation of flow across a 0.4 × 0.4 × 17 m (2.72 m3 volume) parallel-walled column of rendered matrix and vuggy megaporosity indicates a high hydraulic conductivity of 53 m s-1. This value is similar to previous Lattice Boltzmann calculations of hydraulic conductivity in smaller limestone samples of the Biscayne aquifer. The development of simulation methods that reproduce dual-porosity systems with higher resolution and fidelity and that consider flow through horizontally longer renderings could provide improved estimates of the hydraulic conductivity and help to address questions about the importance of scale.

LIDAR optical rugosity of coral reefs in Biscayne National Park, Florida

Science.gov (United States)

Brock, J.C.; Wright, C.W.; Clayton, T.D.; Nayegandhi, A.

2004-01-01

The NASA Experimental Advanced Airborne Research Lidar (EAARL), a temporal waveform-resolving, airborne, green wavelength LIDAR (light detection and ranging), is designed to measure the submeter-scale topography of shallow reef substrates. Topographic variability is a prime component of habitat complexity, an ecological factor that both expresses and controls the abundance and distribution of many reef organisms. Following the acquisition of EAARL coverage over both mid-platform patch reefs and shelf-margin bank reefs within Biscayne National Park in August 2002, EAARL-based optical indices of topographic variability were evaluated at 15 patch reef and bank reef sites. Several sites were selected to match reefs previously evaluated in situ along underwater video and belt transects. The analysis used large populations of submarine topographic transects derived from the examination of closely spaced laser spot reflections along LIDAR raster scans. At all 15 sites, each LIDAR transect was evaluated separately to determine optical rugosity (Rotran), and the average elevation difference between adjacent points (Av(??E ap)). Further, the whole-site mean and maximum values of Ro tran and Av(??Eap) for the entire population of transects at each analysis site, along with their standard deviations, were calculated. This study revealed that the greater habitat complexity of inshore patch reefs versus outer bank reefs results in relative differences in topographic complexity that can be discerned in the laser returns. Accordingly, LIDAR sensing of optical rugosity is proposed as a complementary new technique for the rapid assessment of shallow coral reefs. ?? Springer-Verlag 2004.

Seafloor geomorphology of western Antarctic Peninsula bays: a signature of ice flow behaviour

Science.gov (United States)

Munoz, Yuribia P.; Wellner, Julia S.

2018-01-01

Glacial geomorphology is used in Antarctica to reconstruct ice advance during the Last Glacial Maximum and subsequent retreat across the continental shelf. Analogous geomorphic assemblages are found in glaciated fjords and are used to interpret the glacial history and glacial dynamics in those areas. In addition, understanding the distribution of submarine landforms in bays and the local controls exerted on ice flow can help improve numerical models by providing constraints through these drainage areas. We present multibeam swath bathymetry from several bays in the South Shetland Islands and the western Antarctic Peninsula. The submarine landforms are described and interpreted in detail. A schematic model was developed showing the features found in the bays: from glacial lineations and moraines in the inner bay to grounding zone wedges and drumlinoid features in the middle bay and streamlined features and meltwater channels in the outer bay areas. In addition, we analysed local variables in the bays and observed the following: (1) the number of landforms found in the bays scales to the size of the bay, but the geometry of the bays dictates the types of features that form; specifically, we observe a correlation between the bay width and the number of transverse features present in the bays. (2) The smaller seafloor features are present only in the smaller glacial systems, indicating that short-lived atmospheric and oceanographic fluctuations, responsible for the formation of these landforms, are only recorded in these smaller systems. (3) Meltwater channels are abundant on the seafloor, but some are subglacial, carved in bedrock, and some are modern erosional features, carved on soft sediment. Lastly, based on geomorphological evidence, we propose the features found in some of the proximal bay areas were formed during a recent glacial advance, likely the Little Ice Age.

Saldanha Bay, South Africa I: the use of ocean colour remote ...

African Journals Online (AJOL)

The efficacy of ocean colour remote sensing in assessing the variability of phytoplankton biomass within Saldanha Bay is examined. Satellite estimates of chlorophyll a (Chl a) were obtained using the maximum peak-height (MPH) algorithm on full-resolution (300 m) data from the Medium Resolution Imaging Spectrometer ...

Predominant Nearshore Sediment Dispersal Patterns in Manila Bay

Directory of Open Access Journals (Sweden)

Fernando Siringan

1997-12-01

Full Text Available Net nearshore sediment drift patterns in Manila Bay were determined by combining the coastal geomorphology depicted in 1 : 50,000scale topographic maps and Synthetic Aperture Radar (SAR images, with changes in shoreline position and predominant longshore current directions derived from the interaction of locally generated waves and bay morphology.Manila Bay is fringed by a variety of coastal subenvironments that reflect changing balances of fluvial, wave, and tidal processes. Along the northern coast, a broad tidal-river delta plain stretching from Bataan to Bulacan indicates the importance of tides, where the lateral extent of tidal influences is amplified by the very gentle coastal gradients. In contrast, along the Cavite coast sandy strandplains, spits, and wave-dominated deltas attest to the geomorphic importance of waves that enter the bay from the South China Sea.The estimates of net sediment drift derived from geomorphological, shoreline-change, and meteorological information are generally in good agreement. Sediment drift directions are predominantly to the northeast along Cavite, to the northwest along Manila and Bulacan, and to the north along Bataan. Wave refraction and eddy formation at the tip of the Cavite Spit cause southwestward sediment drift along the coast from Zapote to Kawit. Geomorphology indicates that onshore-offshore sediment transport is probably more important than alongshore transport along the coast fronting the tidal delta plain of northern Manila Bay. Disagreements between the geomorphic-derived and predicted net sediment drift directions may be due to interactions of wave-generated longshore currents with wind- and tide-generated currents.

76 FR 15246 - Anchorage Regulations; Narragansett Bay and Rhode Island Sound, RI

Science.gov (United States)

2011-03-21

...-AA01 Anchorage Regulations; Narragansett Bay and Rhode Island Sound, RI AGENCY: Coast Guard, DHS... Rhode Island Sound south of Brenton Point, Rhode Island, for use by vessels waiting to enter... Sound that under current informal practice is routinely used by mariners as an anchorage while waiting...

Sustainable development in the Hudson Bay/James Bay bioregion

International Nuclear Information System (INIS)

Anon.

1991-01-01

An overview is presented of projects planned for the James Bay/Hudson Bay region, and the expected environmental impacts of these projects. The watershed of James Bay and Hudson Bay covers well over one third of Canada, from southern Alberta to central Ontario to Baffin Island, as well as parts of north Dakota and Minnesota in the U.S.A. Hydroelectric power developments that change the timing and rate of flow of fresh water may cause changes in the nature and duration of ice cover, habitats of marine mammals, fish and migratory birds, currents into and out of Hudson Bay/James Bay, seasonal and annual loads of sediments and nutrients to marine ecosystems, and anadromous fish populations. Hydroelectric projects are proposed for the region by Quebec, Ontario and Manitoba. In January 1992, the Canadian Arctic Resources Committee (CARC), the Environmental Committee of Sanikuluaq, and the Rawson Academy of Arctic Science will launch the Hudson Bay/James Bay Bioregion Program, an independent initiative to apply an ecosystem approach to the region. Two main objectives are to provide a comprehensive assessment of the cumulative impacts of human activities on the marine and freshwater ecosystems of the Hudson Bay/James Bay bioregion, and to foster sustainable development by examining and proposing cooperative processes for decision making among governments, developers, aboriginal peoples and other stakeholders. 1 fig

SOUTH AFRICA AT WAR, 1912-1982

African Journals Online (AJOL)

A three- pronged attack was launched upon the German. Colony; from the south, Luderitzbucht and from. Walvis Bay4 ..... Brigade was sent to the island to replace British troops needed in .... three miles the roads leading to the bridge were.

Cultivation-dependent analysis of the microbial diversity associated with the seagrass meadows in Xincun Bay, South China Sea.

Science.gov (United States)

Jiang, Yu-Feng; Ling, Juan; Wang, You-Shao; Chen, Biao; Zhang, Yan-Ying; Dong, Jun-De

2015-10-01

Microbial communities have largely existed in the seagrass meadows. A total of 496 strains of the bacteria in the seagrass meadows, which belonged to 50 genera, were obtained by the plate cultivation method from three sites of Xincun Bay, South China Sea. The results showed that Bacillales and Vibrionales accounted for the highest proportions of organisms in all communities. The diversity of the bacteria in the sediment was higher than that associated with seagrass. Thalassia hemperichii possessed the highest abundance of bacteria, followed by Enhalus acoroides and Cymodocea rotundata. Robust seasonal dynamics in microbial community composition were also observed. It was found that microbial activities were closely tied to the growth stage of the seagrass. The microbial distribution was the lowest in site 3. The abundance of the bacteria was linked to the interactions between bacteria and plants, the condition of plant and even the coastal water quality and the nutrition level in the sediment.

Oceanic variability in the western sector of Algoa Bay, South Africa ...

African Journals Online (AJOL)

The city of Port Elizabeth lies in the western sector of Algoa Bay, and a number of projects have investigated the oceanic temperature, salinity and current structures in the vicinity. This paper analyses past results, and then incorporates measurements of salinity, sea temperatures and currents from projects over the years ...

Historical occurrence of coho salmon (Oncorhynchus kisutch) in streams of the Santa Cruz Mountain region of California: response to an Endangered Species Act petition to delist coho salmon south of San Francisco Bay

Science.gov (United States)

Brian C. Spence; Walter G. Duffy; John Carlos Garza; Bret Harvey; Susan M. Sogard; Laurie A. Weitkamp; Thomas H. Williams; David A. Boughton

2011-01-01

In November 2003, the National Marine Fisheries Service received a petition from Homer T. McCrary to redefine the southern extent of the Central California Coast Coho Salmon Evolutionarily Significant Unit (CCC Coho Salmon ESU) to exclude populations that spawn in coastal watersheds south of the entrance to San Francisco Bay (i.e., the Golden Gate). The petitioner’s...

Power System Reliability Assessment by Analysing Voltage Dips on the Blue Horizon Bay 22KV Overhead Line in the Nelson Mandela Bay Municipality

Science.gov (United States)

Lamour, B. G.; Harris, R. T.; Roberts, A. G.

2010-06-01

Power system reliability problems are very difficult to solve because the power systems are complex and geographically widely distributed and influenced by numerous unexpected events. It is therefore imperative to employ the most efficient optimization methods in solving the problems relating to reliability of the power system. This paper presents a reliability analysis and study of the power interruptions resulting from severe power outages in the Nelson Mandela Bay Municipality (NMBM), South Africa and includes an overview of the important factors influencing reliability, and methods to improve the reliability. The Blue Horizon Bay 22 kV overhead line, supplying a 6.6 kV residential sector has been selected. It has been established that 70% of the outages, recorded at the source, originate on this feeder.

A field study of littoral processes in Estero Bay, California

Science.gov (United States)

Dingler, J.R.; Anima, R.J.; Molzan, D.E.; Luepke, Gretchen; Peterson, C.L.

1982-01-01

Estero Bay, which lies on the central California coast, has rocky headlands at both ends and sandy beaches within it. The shoreline of the bay has adjusted to be in equilibrium with the predominant wave climate, which is from the northwest. Because of its present shoreline configuration, the net southward littoral transport found along much of the California coast does not occur within Estero Bay. Instead, the sand primarily moves on- and offshore with a reversing longshore component. This sand transport pattern produces a littoral cell within Estero Bay even though there is no submarine canyon in the area. The primary sand sinks for this cell appear to be the sand spit south of Morro Rock and the entrance to Morro Bay itself, although this opinion was not experimentally verified. Field work during one summer (1978) and the following winter (1979) produced baseline data on the profile of and grain-size distribution across the littoral zone. In the offshore part of the littoral zone we also studied ripple size and type, internal structure, depth of erosion, and mineralogy. Although these data, which were collected along nine transects spaced 2 km apart, are inadequate to yield transport and energy rates, they indicate a northward decrease in wave energy within Estero Bay and a mixing of the sediments in the offshore. Box core and rod height data from grid points in seven meters of water showed that on the order of a meter of erosion occurred in the central part of the bay between the two sampling periods. Offshore, the data were incomplete, but at one station, in 17 m of water, at least 20 cm of erosion occurred.

Distribution and behavior of major and trace elements in Tokyo Bay, Mutsu Bay and Funka Bay marine sediments

International Nuclear Information System (INIS)

Honda, Teruyuki; Kimura, Ken-ichiro

2003-01-01

Fourteen major and trace elements in marine sediment core samples collected from the coasts along eastern Japan, i.e. Tokyo Bay (II) (the recess), Tokyo Bay (IV) (the mouth), Mutsu Bay and Funka Bay and the Northwest Pacific basin as a comparative subject were determined by the instrumental neutron activation analysis (INAA). The sedimentation rates and sedimentary ages were calculated for the coastal sediment cores by the 210 Pb method. The results obtained in this study are summarized as follows: (1) Lanthanoid abundance patterns suggested that the major origin of the sediments was terrigenous material. La*/Lu* and Ce*/La* ratios revealed that the sediments from Tokyo Bay (II) and Mutsu Bay more directly reflected the contribution from river than those of other regions. In addition, the Th/Sc ratio indicated that the coastal sediments mainly originated in the materials from the volcanic island-arcs, Japanese islands, whereas those from the Northwest Pacific mainly from the continent. (2) The correlation between the Ce/U and Th/U ratios with high correlation coefficients of 0.920 to 0.991 indicated that all the sediments from Tokyo Bay (II) and Funka Bay were in reducing conditions while at least the upper sediments from Tokyo Bay (IV) and Mutsu Bay were in oxidizing conditions. (3) It became quite obvious that the sedimentation mechanism and the sedimentation environment at Tokyo Bay (II) was different from those at Tokyo Bay (IV), since the sedimentation rate at Tokyo Bay (II) was approximately twice as large as that at Tokyo Bay (IV). The sedimentary age of the 5th layer (8∼10 cm in depth) from Funka Bay was calculated at approximately 1940∼50, which agreed with the time, 1943∼45 when Showa-shinzan was formed by the eruption of the Usu volcano. (author)

Trends in Accretion Rates of Riverine Sediments in a Distal Bay and Wetlands Using 7-Beryllium as a Tracer: Fourleague Bay, Louisiana.

Science.gov (United States)

Restreppo, G. A.; Bentley, S. J.; Wang, J.; Xu, K.

2017-12-01

To combat land loss along the Mississippi River Delta, Louisiana has launched a historic campaign to sustain and regrow coastal lands using, in part, sediment diversions. Previous research has focused primarily on sand sized sediment load, which is usually deposited proximal to a river's delta or a diversion's outlet. Fine sediments constitute the majority of sediment load in the Mississippi, but are under-studied with respect to dispersal processes, particularly in terms of sediment supply to distal deltaic bays and wetlands. The Atchafalaya River and associated wetlands serve as prime study areas for this purpose. Bimonthly time-series push cores were collected from May 2015 to May 2016 along ten sites within Fourleague Bay, Louisiana. Fourleague Bay has remained stable against the deteriorative effects of relative sea level rise, standing out along Louisiana's declining coastline. Of the ten field sites, five are located across a longitudinal transect in the middle bay, while the other five are located in adjacent marshes. All sites fall within 10 to 30 km of the Atchafalaya Delta, extending south towards the Gulf of Mexico. Cores were extruded in 2 cm intervals, dried, ground, and analyzed via gamma spectrometry for the presence of 7Be. Inventories of 7Be were then calculated and used to determine daily mass accretion rate (MAR) over twelve months. Average MAR values for the bay and the marshes are compared with Atchafalaya River discharge, wind data, and atmospheric pressure through the year of sampling. Peak marsh MAR, 0.88 ± 0.20 kg m-2 d-1, occurs just after historically high river discharge. Peak bay MAR, 1.2 ± 0.67 kg m-2 d-1, occurs during seasonal low river discharge and calm winds. Average bay and marsh MARs have a moderate to strong, negative correlation when compared. Results indicate sediment bypass of the bay floor during periods of moderate to high river discharge, entering the marshes directly when inundation occurs and enhanced by the passage

South Carolina Coastal Erosion Study, Data Report for Observations, October 2003 - April 2004

Science.gov (United States)

Sullivan, Charlene M.; Warner, John C.; Martini, Marinna A.; Voulgaris, George; Work, Paul; Haas, Kevin A.; Hanes, Daniel

2006-01-01

Oceanographic observations have been made at nine locations in Long Bay, South Carolina from October 2003 through April 2004. These sites are centered around a shore-oblique sand feature that is approximately 10 km long, 2 km wide, and in excess of 3 m thick. The observations were collected through a collaborative effort with the U.S. Geological Survey, the University of South Carolina, and Georgia Institute of Technology Savannah Campus as part of a larger study to understand the physical processes that control the transport of sediments in Long Bay.

A biological effects monitoring survey of Cardigan Bay using flatfish histopathology, cellular biomarkers and sediment bioassays: findings of the Prince Madog Prize 2003.

Science.gov (United States)

Lyons, Brett P; Stentiford, Grant D; Bignell, John; Goodsir, Freya; Sivyer, David B; Devlin, Michelle J; Lowe, Dave; Beesley, Amanda; Pascoe, Christine K; Moore, Mike N; Garnacho, Eva

2006-07-01

Cardigan Bay on the western coast of the UK is considered a pristine location with much of its coastal and marine habitats protected under various national and EC Directives. Despite this, populations of the flatfish dab (Limanda limanda) captured from Cardigan Bay display elevated levels of liver tumours relative to the background prevalence of the disease. This study describes the findings of a research cruise that took place during November 2003 to assess the prevalence of tumours in dab from selected sites in and around Cardigan Bay. In addition, potential causative mechanisms were investigated via measurement of a range of end points (including composition and abundance of benthic and phytoplankton communities, sediment toxicity and cellular biomarkers of genotoxicity) from sediment, water and biota samples. Fish captured from South Cardigan Bay displayed a relatively higher prevalence of liver tumours compared to those captured from Red Wharf Bay. Hepatocellular adenoma (8% and 2%, respectively) and hepatocellular foci of cell alteration (18% and 6%, respectively) were most prevalent in South Cardigan Bay. Analysis of the sediment failed to distinguish any differences in toxicity between the two sampling sites. However, DNA strand breaks in red blood cells of dab were significantly higher (p < 0.05) in fish collected from Red Warf Bay compared with those sampled at Cardigan Bay. The alignment of biological effects measures via such integrated cruise programs are discussed. This work was partly funded under the auspices of the 2003 Prince Madog Prize.

Seafloor geomorphology of western Antarctic Peninsula bays: a signature of ice flow behaviour

Directory of Open Access Journals (Sweden)

Y. P. Munoz

2018-01-01

Full Text Available Glacial geomorphology is used in Antarctica to reconstruct ice advance during the Last Glacial Maximum and subsequent retreat across the continental shelf. Analogous geomorphic assemblages are found in glaciated fjords and are used to interpret the glacial history and glacial dynamics in those areas. In addition, understanding the distribution of submarine landforms in bays and the local controls exerted on ice flow can help improve numerical models by providing constraints through these drainage areas. We present multibeam swath bathymetry from several bays in the South Shetland Islands and the western Antarctic Peninsula. The submarine landforms are described and interpreted in detail. A schematic model was developed showing the features found in the bays: from glacial lineations and moraines in the inner bay to grounding zone wedges and drumlinoid features in the middle bay and streamlined features and meltwater channels in the outer bay areas. In addition, we analysed local variables in the bays and observed the following: (1 the number of landforms found in the bays scales to the size of the bay, but the geometry of the bays dictates the types of features that form; specifically, we observe a correlation between the bay width and the number of transverse features present in the bays. (2 The smaller seafloor features are present only in the smaller glacial systems, indicating that short-lived atmospheric and oceanographic fluctuations, responsible for the formation of these landforms, are only recorded in these smaller systems. (3 Meltwater channels are abundant on the seafloor, but some are subglacial, carved in bedrock, and some are modern erosional features, carved on soft sediment. Lastly, based on geomorphological evidence, we propose the features found in some of the proximal bay areas were formed during a recent glacial advance, likely the Little Ice Age.

Benthic flux of nutrients and trace metals in the northern component of San Francisco Bay, California

Science.gov (United States)

Kuwabara, James S.; Topping, Brent R.; Parcheso, Francis; Engelstad, Anita C.; Greene, Valerie E.

2009-01-01

Island, the benthic flux of soluble reactive phosphorus (SRP) was consistently: (1) lower than previously reported for South Bay sites, (2) an order of magnitude lower than oligotrophic Coeur d?Alene Lake, (3) two orders of magnitude lower than determined for eutrophic Upper Klamath Lake, and (4) an order of magnitude or more lower than the estimated summer riverine inputs for SRP (900 to 1,300 kilograms of phosphorous per day (kg-P d-1)). In contrast to fluxes reported for the South Bay, nitrate fluxes were consistently negative (that is, drawn from the water column into the sediment), except for one site with statistically insignificant nitrate fluxes (Site 409 within Suisun Bay). The most negative nitrate flux (-7.3?0.1 mmole m-2d-1) was observed within Grizzly Bay (Site 416). Observed nitrate fluxes bracketed the estimated summer fluvial flux of nitrate (3,500 to 5,000 kg-N d-1). With the exception of the two Grizzly Bay sites (416 and 417), the consistently positive benthic flux of ammonia generally counteracted the negative flux of nitrate to yield a net balance of dissolved inorganic nitrogen. Ammonia benthic fluxes extrapolated for Suisun Bay ranged from 320 kg-N d-1 (Site SSB009 near the entrance to Honker Bay) to 1,900 kg-N d-1 (Montezuma Island). These values represent a significant ammonia source to the water column relative to summer riverine inputs (approximately 400 to 600 kg-N d-1). Dissolved silica also displayed a consistently positive benthic flux, except for Site 409 within Suisun Bay, which showed insignificant fluxes (also insignificant for nitrate and SRP). As with the nitrate fluxes, Grizzly Bay and Browns Island sites yielded the highest dissolved silica fluxes (1.3?1.2 to 2.5?0.6 mmole m-2d-1, respectively). These initial diffusive-flux estimates are greater than those measured in the South Bay using core-incubation experiments, which include bioturbation and bioirrigation effects, but they are nevertheless probably one to t

Anomalous Ba/Ca signals associated with low temperature stresses in Porites corals from Daya Bay, northern South China Sea

Institute of Scientific and Technical Information of China (English)

Tianran Chen; Kefu Yu; Shu Li; Tegu Chen; Qi Shi

2011-01-01

Barium to calcium (Ba/Ca) ratio in corals has been considered as a useful geochemical proxy for upwelling,river flood and other oceanic processes.However,recent studies indicated that additional environmental or biological factors can influence the incorporation of Ba into coral skeletons.In this study,Ba/Ca ratios of two Porites corals collected from Daya Bay,northern South China Sea were analyzed.Ba/Ca signals in the two corals were 'anomalous' in comparison with Ba behaviors seen in other near-shore corals influenced by upwelling or riverine runoff.Our Ba/Ca profiles displayed similar and remarkable patterns characterized by low and randomly fluctuating background signals periodically interrupted by sharp and large synchronous peaks,clearly indicating an environmental forcing.Further analysis indicated that the Ba/Ca profiles were not correlated with previously claimed environmental factors such as precipitation,coastal upwelling,anthropogenic activities or phytoplankton blooms in other areas.The maxima of Ba/Ca appeared to occur in the period of Sr/Ca maxima,coinciding with the winter minimum temperatures,which suggests that the anomalous high Ba/Ca signals were related to winter-time low sea surface temperature.We speculated that the Ba/Ca peaks in corals of the Daya Bay were most likely the results of enrichment of Ba-rich particles in their skeletons when coral polyps retracted under the stresses of anomalous winter low temperatures.In this case,Ba/Ca ratio in relatively high-latitude corals can be a potential proxy for tracing the low temperature stress.

Health Effects Due to Radionuclides Content of Solid Minerals within Port of Richards Bay, South Africa

Directory of Open Access Journals (Sweden)

Felix B. Masok

2016-11-01

Full Text Available This study assessed the radiological health hazards to various body organs of workers working within Transnet Precinct in Richards Bay in Kwazulu-Natal, South Africa due to radionuclide content of mineral ores often stored within the facility. Thirty samples were collected from five mineral ores (rock phosphate, rutile, zircon, coal and hematite and analyzed for 238U, 234U, 226Ra, 210Pb, 235U, 232Th, 228Ra, 228Th and 40K using delayed neutron activation analysis and low energy gamma spectroscopy. Rutile was found to be the most radioactive mineral ore within the facility with 210Pb concentration of 759.00 ± 106.00 Bq·kg−1. Effective annual dose rate in (mSv·y−1 delivered to different organs of the body: testes, bone marrow, whole body, lungs and ovaries from mineral ores were such that dose from mineral ores decreased in the order coal > rutile > rock phosphate > hematite > zircon. The organs with the highest received dose rate were the testes and this received dose was from coal. However, all of the calculated absorbed dose rates to organs of the body were below the maximum permissible safety limits.

Cosmic noise absorption and ionospheric currents at the South Pole and Frobisher Bay: Initial results

International Nuclear Information System (INIS)

Rosenberg, T.J.; Wolfe, A.; Lanzerotti, L.J.

1987-01-01

Studies of the conjugacy of auroral and ionospheric phenomena at very high latitudes are an important aspect of magnetospheric physics research. The extent to which auroral phenomena in opposite hemispheres are similar in occurrence and in the details of their temporal, spatial, and spectral characteristics can be used to infer the commonality of the source(s) of the disturbances. At one extreme in this consideration is the questions of whether sources lie on open or closed magnetic field lines. The University of Maryland and AT ampersand T Bell Laboratories have operated riometers and fluxgate magnetometers, respectively, at South Pole since 1982. Corresponding measurements at Frobisher Bay were begun in mid-1985. Riometers record the absorption of cosmic radio noise in the ionosphere produced by the enhances precipitation of energetic charged particles. The studies of the riometer data relate mainly to the effects of the influx of magnetospheric electrons, which give rise to auroral absorption of the cosmic signals. Intense currents (electrojets) that often flow in the ionosphere in association with auroral absorption events produce magnetic field changes that can be recorded on the ground by appropriately sited magnetometers. This report presents some initial results of the comparison of the two data sets

Influence of urbanization and industrialization on metal enrichment of sediment cores from Shantou Bay, South China

International Nuclear Information System (INIS)

Qiao, Yongmin; Yang, Yang; Zhao, Jiangang; Tao, Ran; Xu, Ronghua

2013-01-01

Four sediment cores were collected to investigate geochemical sources and to assess enrichment and pollution of metals in sediments from Shantou Bay, an area experiencing rapid economic development on the Southeastern Coast of China. The results indicated that the concentrations of the majority of metals showed a decrease with depth, with overall maximum values in the top layers, and that different sampling locations in the Bay received slightly different types of inputs. Three major sources were identified by correlation analysis and principal component analysis: river inputs, metropolitan, and port facilities discharge. Calculation of a pollution load index revealed overall low values, but the enrichment factor values for Pb and Cd were typically high for all cores. The mean concentrations of Cu, Pb, Zn and to some extent Cd exceeded the Effects-Range-Low values in the majority of the cases, indicating that there were possible ecotoxicological risks to organisms in Shantou Bay. -- Highlights: •Metals had downward decrease with overall maximum value at top layers. •River input, metropolitan and port facilities discharge are identified as major sources. •Pb and Cd are mainly enriched metals. •Cu, Pb, Zn and Cd had potential ecotoxicological risks to organisms in Shantou Bay. -- Shantou Bay was polluted by Cd, Cu, Pb and Zn, and showed an increase trend along time. River input, metropolitan and port facilities were identified as their sources based on multi-analysis

Hydrodynamic Characteristics and Salinity Patterns in Estero Bay, Lee County, Florida

Science.gov (United States)

Byrne, Michael J.; Gabaldon, Jessica N.

2008-01-01

Estero Bay is an estuary (about 12 miles long and 3 miles wide) on the southwestern Florida coast, with several inlets connecting the bay to the Gulf of Mexico and numerous freshwater tributaries. Continuous stage and salinity data were recorded at eight gaging stations in Estero Bay estuary from October 2001 to September 2005. Continuous water velocity data were recorded at six of these stations for the purpose of measuring discharge. In addition, turbidity data were recorded at four stations, suspended sediment concentration were measured at three stations, and wind measurements were taken at one station. Salinity surveys, within and around Estero Bay, were conducted 15 times from July 2002 to January 2004. The average daily discharge ranged from 35,000 to -34,000 ft3/s (cubic feet per second) at Big Carlos Pass, 10,800 to -11,200 ft3/s at Matanzas Pass, 2,200 to -2,900 ft3/s at Big Hickory Pass, 680 to -700 ft3/s at Mullock Creek, 330 to -370 ft3/s at Estero River, and 190 to -180 ft3/s at Imperial River. Flood tide is expressed as negative discharge and ebb flow as positive discharge. Reduced salinity at Matanzas Pass was negatively correlated (R2 = 0.48) to freshwater discharge from the Caloosahatchee River at Franklin Locks (S-79). Matanzas Pass is hydrologically linked to Hell Peckney Bay; therefore, water-quality problems associated with the Caloosahatchee River also affect Hell Peckney Bay. Rocky Bay was significantly less saline than Coconut Point and Matanzas Pass was significantly less saline than Ostego Bay, based on data from the salinity surveys. The quality-checked and edited continuous data and the salinity maps have been compiled and are stored on the U.S. Geological Survey South Florida Information Access (SOFIA) website (http://sofia.usgs.gov).

Humic Substances from Manila Bay and Bolinao Bay Sediments

Directory of Open Access Journals (Sweden)

Elma Llaguno

1997-12-01

Full Text Available The C,H,N composition of sedimentary humic acids (HA extracted from three sites in Manila Bay and six sites in Bolinao Bay yielded H/C atomic ratios of 1.1-1.4 and N/C atomic ratios of 0.09 - 0.16. The Manila Bay HA's had lower H/C and N/C ratios compared to those from Bolinao Bay. The IR spectra showed prominent aliphatic C-H and amide I and II bands. Manila Bay HA's also had less diverse molecular composition based on the GC-MS analysis of the CuO and alkaline permanganate oxidation products of the humic acids.

Long-Term Water Temperature Variations in Daya Bay, China Using Satellite and In Situ Observations

Directory of Open Access Journals (Sweden)

Jing Yu

2010-01-01

Full Text Available Daya Bay is a shallow, semi-en closed bay in the northern section of the South China Sea. The present study analyzed variations of water temperature in Daya Bay over the past 21 years (1985 - 2005 using Advanced Very High Resolution Radiometer (AVHRR satellite remote sensing data and in situ observations. Results showed that AVHRR readings of sea surface temperature (SST increased by 0.07°C y-1. Linear regression anal y sis for monthly SST anomalies (SSTA showed a shift from negative to positive from 1995 - 1996, when the Daya Bay nuclear power station commenced operations in 1994. The slope of linear regression analysis for SSTA nearly doubled from 0.05 (1985 - 1993 to 0.09 (1994 - 2005. Monthly AVHRR images showed a thermal plume from the power station and revealed the in crease of SST over 21 years. In situ observations in water temperature also showed an in creasing trend for the same period (1985 - 2005. Variations in water temperature in Daya Bay were connected with climatic perturbations and in creasing human activity including thermal discharge from nuclear power stations and the rapid economic development around the bay area.

Preliminary bathymetry of Blackstone Bay and Neoglacial changes of Blackstone Glaciers, Alaska

Science.gov (United States)

Post, Austin

1980-01-01

Preliminary bathymetry (at 1:20,000 scale) and scientific studies of Blackstone Bay Alaska, by the Research Vessel Growler in 1978 disclose that the head of the bay consists of two basins separated by Willard Island and a submarine ridge. Both basins are closed on the north by terminal-moraine bars where Blackstone Glacier and its tributaries terminated as recently as about A.D. 1350; a carbon-14 date of 580 years before present on Badger Point, and old trees farther up the bay, disclose that the glaciers retreated to two narrow inlets at the head of the bay before 1400. The inlets were still glacier-covered until at least 1909. Glaciers in both inlets have continued to retreat; at present they terminate at the head of tidewater, where they discharge small icebergs. Only relatively thin sediments have accumulated in the eastern basin south of the terminal-moraine bar, and most of the bottom is hard and irregular as disclosed by soundings and profiles. The northern part of Blackstone Bay is very deep; at more than 1,100 feet below sea level a large, level accumulation of sediment is present which is presumably as much as 1,000 feet deep and has been accumulating since late Pleistocene glaciers retreated. (USGS)

Electromagnetic methods for rapidly characterizing porosity distributions in the upper part of the Biscayne aquifer, southern Florida

Science.gov (United States)

Mount, G. J.; Comas, X.; Cunningham, K. J.

2010-12-01

Gregory J. Mount1, Xavier Comas1, and Kevin J. Cunningham2 1Department of Geosciences, Florida Atlantic University, Boca Raton, Florida 33431 2U.S. Geological Survey, 3110 SW 9th Avenue, Fort Lauderdale, Florida 33315 Although conventional hydrological techniques of aquifer characterization, which rely on data obtained from boreholes and wells can provide very valuable direct information about porosity, storativity and transmissivity, they are invasive and can often become time consuming and relatively expensive. Near-surface electromagnetic techniques, such as ground penetrating radar (GPR), provide indirect measurements of aquifer properties that complement traditional point measurements and provide a laterally continuous subsurface image in an efficient and cost effective manner with a minimal impact on the environment. We investigated the carbonate rocks of the uppermost part (3-5 meters) of the Biscayne aquifer in Everglades National Park to better understand the distribution of karst features that can create concentrated flow of groundwater, nutrients, and contaminants. As the Biscayne aquifer is the primary source of drinking water for millions of people in southern Palm Beach, Broward, and Miami-Dade counties, knowledge about these features could create a more complete understanding of a critical natural resource. These macroporous elements contribute to the overall storage, permeability, and transmissivity of the aquifer and for that reason, delineation of their distribution and areal extent should aid in the development of more accurate groundwater flow models. The macroporous elements create numerous hyperbolic diffractions in GPR common offset profiles, and these diffractions are used directly used to estimate two-dimensional (2D) models of electromagnetic (EM) wave velocity in the subsurface. Such models are further contrasted with one-dimensional (1D) velocity models using GPR common mid-point surveys at selected locations. In order to estimate

Riverine discharges to Chesapeake Bay: Analysis of long-term (1927–2014) records and implications for future flows in the Chesapeake Bay basin

Science.gov (United States)

Rice, Karen; Moyer, Douglas; Mills, Aaron L.

2017-01-01

The Chesapeake Bay (CB) basin is under a total maximum daily load (TMDL) mandate to reduce nitrogen, phosphorus, and sediment loads to the bay. Identifying shifts in the hydro-climatic regime may help explain observed trends in water quality. To identify potential shifts, hydrologic data (1927–2014) for 27 watersheds in the CB basin were analyzed to determine the relationships among long-term precipitation and stream discharge trends. The amount, frequency, and intensity of precipitation increased from 1910 to 1996 in the eastern U.S., with the observed increases greater in the northeastern U.S. than the southeastern U.S. The CB watershed spans the north-to-south gradient in precipitation increases, and hydrologic differences have been observed in watersheds north relative to watersheds south of the Pennsylvania—Maryland (PA-MD) border. Time series of monthly mean precipitation data specific to each of 27 watersheds were derived from the Precipitation-elevation Regression on Independent Slopes Model (PRISM) dataset, and monthly mean stream-discharge data were obtained from U.S. Geological Survey streamgage records. All annual precipitation trend slopes in the 18 watersheds north of the PA-MD border were greater than or equal to those of the nine south of that border. The magnitude of the trend slopes for 1927–2014 in both precipitation and discharge decreased in a north-to-south pattern. Distributions of the monthly precipitation and discharge datasets were assembled into percentiles for each year for each watershed. Multivariate correlation of precipitation and discharge within percentiles among the groups of northern and southern watersheds indicated only weak associations. Regional-scale average behaviors of trends in the distribution of precipitation and discharge annual percentiles differed between the northern and southern watersheds. In general, the linkage between precipitation and discharge was weak, with the linkage weaker in the northern watersheds

Planktonic copepod community in the neritic area south western part of Tunis bay influenced by Meliane river supplies (south western Mediterranean sea)

OpenAIRE

Ben Lamine, Y.; Daly Yahia Kefi, O.; Daly Yahia, N.

2012-01-01

The Tunis bay is located in the North Estern coast of Tunisia and receives in its Western part flows from Meliane River. Our study aims to describe the composition and the spatiotemporal distribution of planktonic copepods in the bay in order to identify the effect of the Meliane River supplies on the community. A grid of 19 stations was investigated monthly from July 2004 to December 2004 using a 160 μm mesh size plankton net, towed obliquely from the bottom to the surface. The planktonic co...

Phytoplankton distribution and their relationship to environmental variables in Sanya Bay, South China Sea

Directory of Open Access Journals (Sweden)

Yanying Zhang

2010-11-01

Full Text Available Phytoplankton quantification was conducted in Sanya Bay from January 2005 to February 2006. A submersible in situ spectrofluorometer, which permits the differentiation of four algal groups (green algae, diatoms and dinoflagellates, cryptophytes and cyanobacteria was used. Seasonal variation of total chlorophyll a concentration showed that high value appeared in summer and low concentration occurred in spring. Diatoms and dinoflagellates group was the predominant phytoplankton all year in the Bay. The stable stratification of phytoplankton vertical distribution came into being in July. During the stratification event, the total chlorophyll a concentration of deep layer was much higher than the surface; cyanobacteria and cryptophyta groups decreased and almost disappeared, however, the concentration of green algae and diatoms and dinoflagellates groups increased. In deep layer, the concentration of diatoms and dinoflagellates group increased sharply, which was about eight times more than that in the surface layer. The vertical profiles character of phytoplankton showed that from inshore stations to outer bay the stratification of phytoplankton vertical distribution gradually strengthened. Dissolved inorganic nutrient especially phosphate and inorganic nitrogen and cold-water upwelling were the main regulating factor for phytoplankton distribution.

Potential risk to wood storks (Mycteria americana) from mercury in Carolina Bay fish

International Nuclear Information System (INIS)

Brant, H.A.; Jagoe, C.H.; Snodgrass, J.W.; Bryan, A.L.; Gariboldi, J.C.

2002-01-01

Fish mercury levels from some Carolina bays pose risk to wood stork. - Carolina bays are freshwater wetlands that serve as important feeding habitats for the endangered wood stork (Mycteria americana). Water levels in these bays fluctuate greatly and tend to be acidic and rich in dissolved organic carbon (DOC), factors that favor mercury (Hg) methylation and bioaccumulation in fish. To assess potential risks to wood storks consuming mercury contaminated fish in bays, we sampled fish from 10 bays on the Savannah River Site (SRS), South Carolina, an area with documented use by wood storks. Whole body mercury concentrations in 258 fishes of three species (Erimyzon sucetta, Acantharchus pomotis and Esox americanus) commonly consumed by wood storks were determined. Risk factors for nestlings and free-ranging adults were calculated using published no and lowest observable adverse effect concentration (NOAEC and LOAEC) values for birds. Fish from higher trophic levels and those from wetlands with relatively shallow maximum depths and fluctuating water levels were more likely to exceed NOAEC and LOAEC values. Calculation of exposure rates of nestling wood storks indicated they are at highest risk during the first 10 days of the nestling period. These calculations suggest that there is potential concern for wood storks foraging in relatively shallow bays with fluctuating water levels, even though there is no obvious local source of mercury to these wetlands

Mercury pollution in sediments, benthic organisms and inshore fishes of Haifa Bay, Israel

Energy Technology Data Exchange (ETDEWEB)

Hornung, H; Krumgalz, B S; Cohen, Y

1984-01-01

Total mercury concentrations were determined in surficial sediments, eleven species of benthic organisms and six species of fish from Haifa Bay, Israel. The results show that essentially all of the shallow water zone of the Bay receives anthropogenic mercury. A mercury-cell chlor-alkali plant was identified as the source of pollution. Surficial sediments in vicinity of the plant, containing up to 0.99 micro-g Hg/g dry weight, were up to 157 times enriched in mercury relative to an unpolluted area. Mercury levels in the benthic organisms reflected the levels in the sediments. Maximal concentrations reaching 38.7 and 18.2 micro-g Hg/g dry weight were found in the carnivorous gastropod mollusks Arcularia circumcinta and Arcularia gibbosula, respectively. In all fish species, specimens caught in Haifa Bay had higher mercury concentrations in the muscle tissue than specimens caught south of the Bay. A maximal value of 1.66 micro-g Hg/g wet weight was recorded in Diplodus sargus. 17 references, 3 figures, 3 tables.

Mercury dynamics in a coastal aquifer: Maunalua Bay, O´ahu, Hawai´i

Science.gov (United States)

Ganguli, Priya M.; Swarzenski, Peter W.; Dulaiova, Henrieta; Glenn, Craig R.; Flegal, A. Russell

2014-03-01

We evaluated the influence of groundwater-seawater interaction on mercury dynamics in Maunalua Bay, a coral reef ecosystem located on the south shore of O´ahu, Hawai´i, by combining geochemical data with submarine groundwater discharge (SGD) rates. During a rising tide, unfiltered total mercury (U-HgT) concentrations in seawater increased from ˜6 to 20 pM at Black Point (west Bay) and from ˜2.5 to 8 pM at Niu (central Bay). We attribute this change to an increase in suspended particulate matter at high tide. Approximately 90% of mercury in groundwater at Niu was in the filtered (weighted average Maunalua Bay groundwater mercury flux of 0.68 ± 0.67 mol yr-1 by combining the proportional flux of F-HgT from three distinct SGD zones, and place these results into a broader context by comparing and contrasting flux estimates from locations around the world. Results from existing SGD studies should be evaluated to develop future sampling strategies that address more targeted questions about mercury biogeochemical cycling at the groundwater-seawater interface.

The influence of seagrass on shell layers and Florida Bay mudbanks

Science.gov (United States)

Prager, E.J.; Halley, R.B.

1999-01-01

Aerial photography indicates that sometime since the early 1970's, an emergent ridge of shell debris developed on a mudbank north of Calusa Key in Florida Bay. Coarse shell deposits on and within the Bay's shallow mudbanks are believed to be the product of transport during major storm events and subsequent winnowing. However, shell material from the ridge contains nuclear bomb 14C, supporting formation within the past 30 years and the last major hurricanes to influence Florida Bay were Donna and Betsy (1960 and 1965). Results from this study suggest that the Calusa ridge and other coarse shell deposits in Florida Bay can result from, 1) periodic seagrass mortality and wave-induced transport during frequent winter cold fronts and/or 2) mollusc blooms and subsequent burial. A survey of bottom types indicates that dense to intermediate beds of seagrass, mainly Thalassia testudinum (turtle grass), occur within the shallow basins of western Florida Bay and along the margins of Bay mudbanks. Wave measurements and modeling indicate that Thalassia along mudbank margins can reduce incoming wave-energy by over 80%. Seagrass beds also host particularly dense populations of molluscs from periodic 'blooms' and are believed to be the major source of coarse sediments in the Bay. Thus, if bank-edge seagrass dies, sediments, including shell debris, become exposed and subject to greatly increased wave energy. Modeling indicates that winds typical of winter cold fronts in South Florida can produce near-bottom velocities and shear stress at a grass-free bank edge which are sufficient to transport coarse carbonate grains. Shell layers found at depth in mudbank cores can also be explained by previous episodes of sediment accretion over mollusc-rich seagrass beds or grass bed mortality at the edge of a mudbank and shell transport during cold front passage. The latter implies that mortality of marginal seagrass beds has occurred throughout the history of Florida Bay and that the

Export of a Winter Shelf Phytoplankton Bloom at the Shelf Margin of Long Bay (South Atlantic Bight, USA)

Science.gov (United States)

Nelson, J.; Seim, H.; Edwards, C. R.; Lockhart, S.; Moore, T.; Robertson, C. Y.; Amft, J.

2016-02-01

A winter 2012 field study off Long Bay (seaward of Myrtle Beach, South Carolina) investigated exchange processes along the shelf margin. Topics addressed included mechanisms of nutrient input (upper slope to outer shelf), phytoplankton blooms and community characteristics (mid-to-outer shelf), and possible export of shelf bloom material (transport to and across the shelf break to the upper slope). Observations utilized three moorings (mid-shelf, shelf break, upper slope), two gliders and ship operations (repeat cruises with profiling, water sampling and towed body surveys) along with satellite SST and ocean color imagery and near-by NOAA buoy records. Here we focus on the late January to early February period, when a mid-shelf bloom of Phaeocystis globosa (which forms large gelatinous colonies) was transported to the shelf break. The presence of Phaeocystis colonies resulted in strong spiking in chlorophyll (chl) fluorescence profiles. A partitioning approach was adapted to estimate chl in colonies (spikes) and small forms (baseline signal) and to account for an apparent difference in measured in vivo fluorescence per unit chl (lower in colonies). Up to 40-50% of chl in the bloom (surface to bottom on the mid-shelf) was estimated to be in the colonies. In late January, there a pronounced seaward slumping of relatively dense mid-shelf water along the bottom under warmer surface water derived from the inshore edge of a broad jet of Gulf Stream water flowing southwestward along the upper slope. We describe the evolution of this event and the conditions which set up this mechanism for episodic near-bed transport of fresh bloom material produced on the shelf to the upper slope off Long Bay. Down-slope transport may have been enhanced in this case by the high phytoplankton biomass in gelatinous colonies, which appeared to be settling in the water column on the shelf prior to the transport event.

Developing a community owned wind farm, with social and economic benefits for a low-income community, at St Helena Bay, Western Cape, South Africa

Energy Technology Data Exchange (ETDEWEB)

Lewin, J. [Seeland Development Trust (South Africa); Chown, D. [Genesis Eco-Energy, Cape Town (South Africa); Townsend, N. [Oxfam (United Kingdom)

2008-07-01

This paper described the development of a wind farm at St. Helena Bay in South Africa that involved the collaboration of the Seeland Development Trust, Genesis Eco-Energy and Oxfam. Some of the challenges that have emerged were presented along with the solutions that have been found to those problems, many of which are applicable to other communities attempting to undertake a similar project. The primary objective of this project was to develop a substantially community owned, renewable energy power project, from which revenues will be used to contribute to a range of social and economic development projects. The project, which is in the early stages of development, will have additional benefits, such as job creation, reductions in carbon dioxide emissions, development of alternative financial models for the development of renewable energy and the demonstration of renewable energy as an economically viable opportunity in South Africa. The project site was acquired by the Seeland Development Trust under the South African Government's land restitution process, and is to be used to address issues of poverty, economic development and job creation. This paper described the unique partnership of a local community, a private sector company and a global charity, and presented the business and ownership models that have been developed to achieve the overall objective of the wind energy project.

Remotely Sensing Pollution: Detection and Monitoring of PCBs in the San Francisco Bay

Science.gov (United States)

Hilton, A.; Kudela, R. M.; Bausell, J.

2016-12-01

While the EPA banned polychlorinated biphenyls (PCBs) in 1977, they continue to persist in San Francisco Bay (SF Bay), often at dangerously high concentrations due to their long half-life. However, in spite of their associated health and environmental risks, PCB monitoring within SF Bay is extremely limited, due in large part to the high costs, both in terms of labor and capital that are associated with it. In this study, a cost effective alternative to in-situ PCB sampling is presented by demonstrating the feasibility of PCB detection via remote sensing. This was done by first establishing relationships between in-situ measurements of sum of 40 PCB concentrations and total suspended sediment concentration (SSC) collected from 1998-2006 at 37 stations distributed throughout SF Bay. A correlation was discovered for all stations at (R2 =0.32), which improved markedly upon partitioning stations into north bay, (R2 =0.64), central bay (R2 =0.80) and south bay (R2 =0.52) regions. SSC was then compared from three USGS monitoring stations with temporally consistent Landsat 8 imagery. The resulting correlation between Landsat 8 (Rrs 654) and SSC measured at USGS stations (R2 =0.50) was validated using an Airborne Visible/ Infrared Imaging Spectrometer (AVIRIS) image. The end product is a two-step empirical algorithm that can derive PCB from Landsat 8 imagery within SF Bay. This algorithm can generate spatial PCB concentration maps for SF Bay, which can in turn be utilized to increase ability to forecast PCB concentration. The observation that correlation between AVIRIS (Rrs 657) and SSC was stronger than that of Landsat 8 suggests that the accuracy of this algorithm could be enhanced with improved atmospheric correction.

Bat response to carolina bays and wetland restoration in the southeastern U.S. Coastal Plain.

Energy Technology Data Exchange (ETDEWEB)

Menzel, Jennifer M.; Michael A. Menzel; John C. Kilgo; W. Mark Ford; ; John W. Edwards.

2005-09-01

Abstract: Bat activity in the southeastern United States is concentrated over riparian areas and wetland habitats. The restoration and creation of wetlands for mitigation purposes is becoming common in the Southeast. Understanding the effects of these restoration efforts on wetland flora and fauna is thus becoming increasingly important. Because bats (Order: Chiroptera) consist of many species that are of conservation concern and are commonly associated with wetland and riparian habitats in the Southeast (making them a good general indicator for the condition of wetland habitats), we monitored bat activity over restored and reference Carolina bays surrounded by pine savanna (Pinus spp.) or mixed pine-hardwood habitat types at the Savannah River Site in South Carolina. In order to determine how wetland restoration efforts affected the bat community, we monitored bat activity above drained Carolina bays pre- and post-restoration. Our results indicate that bat activity was greater over reference (i.e., undrained) than drained bays prior to the restorative efforts. One year following combined hydrologic and vegetation treatment, however, bat activity was generally greater over restored than reference bays. Bat activity was also greater over both reference and restored bays than in random, forested interior locations. We found significantly more bat activity after restoration than prior to restoration for all but one species in the treatment bays, suggesting that Carolina bay restoration can have almost immediate positive impacts on bat activity.

Hydrography and circulation in the western Bay of Bengal during the northeast monsoon

Digital Repository Service at National Institute of Oceanography (India)

Shetye, S.R.; Gouveia, A.D.; Shankar, D.; Shenoi, S.S.C.; Vinayachandran, P.N.; Sundar, D.; Michael, G.S.; Nampoothiri, G.

, the transport is 7.7 x 10 sup(6) m sup(3) s sup(-1) . Recent model studies lead us to conclude that the EICC during the northeast monsoon is driven by winds along the east coast of India and Ekman pumping in the interior bay. In the south, Ekman pumping over...

Investigation of the height dependency of optical turbulence in the surface layer over False Bay (South Africa)

Science.gov (United States)

Sprung, Detlev; van Eijk, Alexander M. J.; Günter, Willie; Griffith, Derek; Eisele, Christian; Sucher, Erik; Seiffer, Dirk; Stein, Karin

2017-09-01

Atmospheric turbulence impacts on the propagation of electro-optical radiation. Typical manifestations of optical turbulence are scintillation (intensity fluctuations), beam wander and (for laser systems) reduction of beam quality. For longer propagation channels, it is important to characterize the vertical and horizontal distribution (inhomogeneity) of the optical turbulence. In the framework of the First European South African Transmission ExpeRiment (FESTER) optical turbulence was measured between June 2015 and February 2016 over a 1.8 km over-water link over False Bay. The link ran from the Institute of Maritime Technology (IMT) at Simons Town to the lighthouse at Roman Rock Island. Three Boundary layer scintillometers (BLS900) allowed assessing the vertical distribution of optical turbulence at three different heights between 5 and 12 m above the water surface. The expected decrease with Cn2 with height is not always found. These results are analyzed in terms of the meteorological scenario, and a comparison is made with a fourth optical link providing optical turbulence data over a 8.69 km path from IMT to St. James, roughly perpendicular to the three 1.8 km paths.

Remote sensing applied to numerical modelling. [water resources pollution

Science.gov (United States)

Sengupta, S.; Lee, S. S.; Veziroglu, T. N.; Bland, R.

1975-01-01

Progress and remaining difficulties in the construction of predictive mathematical models of large bodies of water as ecosystems are reviewed. Surface temperature is at present the only variable than can be measured accurately and reliably by remote sensing techniques, but satellite infrared data are of sufficient resolution for macro-scale modeling of oceans and large lakes, and airborne radiometers are useful in meso-scale analysis (of lakes, bays, and thermal plumes). Finite-element and finite-difference techniques applied to the solution of relevant coupled time-dependent nonlinear partial differential equations are compared, and the specific problem of the Biscayne Bay and environs ecosystem is tackled in a finite-differences treatment using the rigid-lid model and a rigid-line grid system.

Occurrence and distribution of antibiotics in coastal water of the Bohai Bay, China: Impacts of river discharge and aquaculture activities

International Nuclear Information System (INIS)

Zou Shichun; Xu Weihai; Zhang Ruijie; Tang Jianhui; Chen Yingjun; Zhang Gan

2011-01-01

The presence of 21 antibiotics in six different groups was investigated in coastal water of the Bohai Bay. Meantime, to illuminate the potential effects caused by the river discharge and aquaculture activities, wastewater from three breeding plants and surface water from six rivers flowing into the Bohai Bay were also analyzed for the selected antibiotics. The result revealed that measured antibiotics in the North Bobai Bay were generally higher than those in the South, highlighting the remarkable effects of high density of human activities on the exposure of antibiotics in environment. The antibiotics found in the six rivers were generally higher than those in the Bohai Bay reflecting the important antibiotics source of river discharge. This study reveals that the high consumption of some antibiotics in aquaculture activities may pose high ecological risk to the bay. - Highlights: → Some antibiotics were ubiquitous with high concentration in the Bohai bay, North China. → The antibiotics were mainly from the six rivers discharge around the Bay. → Antibiotics are commonly used in aquaculture activities around the Bay. → Aquaculture was suggested to be an important antibiotics source in the Bay. - River discharge and aquaculture were suggested to be important sources for antibiotics occurred in the coastal water of the Bohai Bay, North China.

Effects of human disturbance on waterbird nesting and reproductive success at restoration pond SF2, south San Francisco Bay, California

Science.gov (United States)

Ackerman, Joshua T.; Herzog, Mark P.; Hartman, Christopher A.

2014-01-01

To offset for the loss of managed pond habitat during restoration of wetlands to tidal marsh, the South Bay Salt Pond (SBSP) Restoration Project is enhancing some of the remaining ponds by constructing islands for roosting and nesting waterbirds. Among these wetland habitats, the SBSP Restoration Project also is installing walking trails and viewing platforms in an effort to bring the public closer to nature. In winter of 2010–11, the SBSP Restoration Project constructed 30 islands in Pond SF2 and walking trails and viewing platforms around the edge of the pond. The restoration project partners acknowledged that human disturbance could detrimentally affect nesting and roosting waterbirds. Although optimal buffer distances and potential for human disturbance were unknown, islands in Pond SF2, nevertheless, were designed with built-in buffers of greater than 300 feet (91 meters) from a trail and 600 feet (182 meters) from a viewing platform in order to minimize potential human disturbances.

Biodiversity inventories and conservation of the marine fishes of Bootless Bay, Papua New Guinea

Science.gov (United States)

2012-01-01

Background The effective management and conservation of biodiversity is predicated on clearly defined conservation targets. Species number is frequently used as a metric for conservation prioritization and monitoring changes in ecosystem health. We conducted a series of synoptic surveys focusing on the fishes of the Bootless Bay region of Papua New Guinea to generate a checklist of fishes of the region. Bootless Bay lies directly south of Port Moresby, the capital of Papua New Guinea, and experiences the highest human population density of any marine area in the country. Our checklist will set a baseline against which future environmental changes can be tracked. Results We generated a checklist of 488 fish species in 72 families found in Bootless Bay during a two-week sampling effort. Using incident-based methods of species estimation, we extrapolate there to be approximately 940 fish species in Bootless Bay, one of the lowest reported numbers in Papua New Guinea. Conclusions Our data suggest that the Bootless Bay ecosystem of Papua New Guinea, while diverse in absolute terms, has lower fish biodiversity compared to other shallow marine areas within the country. These differences in faunal diversity are most likely a combination of unequal sampling effort as well as biophysical factors within Bootless Bay compounded by historical and/or contemporary anthropogenic disturbances. PMID:22849436

Biodiversity inventories and conservation of the marine fishes of Bootless Bay, Papua New Guinea

Directory of Open Access Journals (Sweden)

Drew Joshua A

2012-08-01

Full Text Available Abstract Background The effective management and conservation of biodiversity is predicated on clearly defined conservation targets. Species number is frequently used as a metric for conservation prioritization and monitoring changes in ecosystem health. We conducted a series of synoptic surveys focusing on the fishes of the Bootless Bay region of Papua New Guinea to generate a checklist of fishes of the region. Bootless Bay lies directly south of Port Moresby, the capital of Papua New Guinea, and experiences the highest human population density of any marine area in the country. Our checklist will set a baseline against which future environmental changes can be tracked. Results We generated a checklist of 488 fish species in 72 families found in Bootless Bay during a two-week sampling effort. Using incident-based methods of species estimation, we extrapolate there to be approximately 940 fish species in Bootless Bay, one of the lowest reported numbers in Papua New Guinea. Conclusions Our data suggest that the Bootless Bay ecosystem of Papua New Guinea, while diverse in absolute terms, has lower fish biodiversity compared to other shallow marine areas within the country. These differences in faunal diversity are most likely a combination of unequal sampling effort as well as biophysical factors within Bootless Bay compounded by historical and/or contemporary anthropogenic disturbances.

33 CFR 110.194a - Mobile Bay, Ala., and Mississippi Sound, Miss.

Science.gov (United States)

2010-07-01

... Sound, Miss. 110.194a Section 110.194a Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Mississippi Sound, Miss. (a) The anchorage grounds. (1) The waters of lower Mobile Bay, near Cedar Point... south by latitude 30°20′00″, and on the west by longitude 88°06′00″. (2) The waters of Mississippi Sound...

33 CFR 100.919 - International Bay City River Roar, Bay City, MI.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 1 2010-07-01 2010-07-01 false International Bay City River Roar, Bay City, MI. 100.919 Section 100.919 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Bay City River Roar, Bay City, MI. (a) Regulated Area. A regulated area is established to include all...

Occurrence and distribution of antibiotics in coastal water of the Bohai Bay, China: impacts of river discharge and aquaculture activities.

Science.gov (United States)

Zou, Shichun; Xu, Weihai; Zhang, Ruijie; Tang, Jianhui; Chen, Yingjun; Zhang, Gan

2011-10-01

The presence of 21 antibiotics in six different groups was investigated in coastal water of the Bohai Bay. Meantime, to illuminate the potential effects caused by the river discharge and aquaculture activities, wastewater from three breeding plants and surface water from six rivers flowing into the Bohai Bay were also analyzed for the selected antibiotics. The result revealed that measured antibiotics in the North Bobai Bay were generally higher than those in the South, highlighting the remarkable effects of high density of human activities on the exposure of antibiotics in environment. The antibiotics found in the six rivers were generally higher than those in the Bohai Bay reflecting the important antibiotics source of river discharge. This study reveals that the high consumption of some antibiotics in aquaculture activities may pose high ecological risk to the bay. Copyright © 2011 Elsevier Ltd. All rights reserved.

Mercury dynamics in a coastal aquifer: Maunalua Bay, Oʻahu, Hawaiʻi

Science.gov (United States)

Ganguli, Priya M.; Swarzenski, Peter W.; Dulaiova, Henrieta; Glenn, Craig R.; Flegal, A. Russell

2014-01-01

We evaluated the influence of groundwater–seawater interaction on mercury dynamics in Maunalua Bay, a coral reef ecosystem located on the south shore of Oʻahu, Hawaiʻi, by combining geochemical data with submarine groundwater discharge (SGD) rates. During a rising tide, unfiltered total mercury (U-HgT) concentrations in seawater increased from ∼6 to 20 pM at Black Point (west Bay) and from ∼2.5 to 8 pM at Niu (central Bay). We attribute this change to an increase in suspended particulate matter at high tide. Approximately 90% of mercury in groundwater at Niu was in the filtered (weighted average Maunalua Bay groundwater mercury flux of 0.68 ± 0.67 mol yr−1 by combining the proportional flux of F-HgT from three distinct SGD zones, and place these results into a broader context by comparing and contrasting flux estimates from locations around the world. Results from existing SGD studies should be evaluated to develop future sampling strategies that address more targeted questions about mercury biogeochemical cycling at the groundwater–seawater interface.

Development of a virtual wave buoy system for the Port of Cape Town, South Africa

CSIR Research Space (South Africa)

Rossouw, Marius

2005-07-01

Full Text Available The Port of Cape Town is located in Table Bay on the south-west coast of South Africa. Since the port experiences advese weather conditions, especially during the winter period, the monitoring of marine weather and wave conditions forms an integral...

Estimating the Cumulative Ecological Effect of Local Scale Landscape Changes in South Florida

Science.gov (United States)

Hogan, Dianna M.; Labiosa, William; Pearlstine, Leonard; Hallac, David; Strong, David; Hearn, Paul; Bernknopf, Richard

2012-01-01

Ecosystem restoration in south Florida is a state and national priority centered on the Everglades wetlands. However, urban development pressures affect the restoration potential and remaining habitat functions of the natural undeveloped areas. Land use (LU) planning often focuses at the local level, but a better understanding of the cumulative effects of small projects at the landscape level is needed to support ecosystem restoration and preservation. The South Florida Ecosystem Portfolio Model (SFL EPM) is a regional LU planning tool developed to help stakeholders visualize LU scenario evaluation and improve communication about regional effects of LU decisions. One component of the SFL EPM is ecological value (EV), which is evaluated through modeled ecological criteria related to ecosystem services using metrics for (1) biodiversity potential, (2) threatened and endangered species, (3) rare and unique habitats, (4) landscape pattern and fragmentation, (5) water quality buffer potential, and (6) ecological restoration potential. In this article, we demonstrate the calculation of EV using two case studies: (1) assessing altered EV in the Biscayne Gateway area by comparing 2004 LU to potential LU in 2025 and 2050, and (2) the cumulative impact of adding limestone mines south of Miami. Our analyses spatially convey changing regional EV resulting from conversion of local natural and agricultural areas to urban, industrial, or extractive use. Different simulated local LU scenarios may result in different alterations in calculated regional EV. These case studies demonstrate methods that may facilitate evaluation of potential future LU patterns and incorporate EV into decision making.

Geology and structure of the North Boqueron Bay-Punta Montalva Fault System

Science.gov (United States)

Roig Silva, Coral Marie

The North Boqueron Bay-Punta Montalva Fault Zone is an active fault system that cuts across the Lajas Valley in southwestern Puerto Rico. The fault zone has been recognized and mapped based upon detailed analysis of geophysical data, satellite images and field mapping. The fault zone consists of a series of Cretaceous bedrock faults that reactivated and deformed Miocene limestone and Quaternary alluvial fan sediments. The fault zone is seismically active (ML < 5.0) with numerous locally felt earthquakes. Focal mechanism solutions and structural field data suggest strain partitioning with predominantly east-west left-lateral displacements with small normal faults oriented mostly toward the northeast. Evidence for recent displacement consists of fractures and small normal faults oriented mostly northeast found in intermittent streams that cut through the Quaternary alluvial fan deposits along the southern margin of the Lajas Valley, Areas of preferred erosion, within the alluvial fan, trend toward the west-northwest parallel to the on-land projection of the North Boqueron Bay Fault. Beyond the faulted alluvial fan and southeast of the Lajas Valley, the Northern Boqueron Bay Fault joins with the Punta Montalva Fault. The Punta Montalva Fault is defined by a strong topographic WNW lineament along which stream channels are displaced left laterally 200 meters and Miocene strata are steeply tilted to the south. Along the western end of the fault zone in northern Boqueron Bay, the older strata are only tilted 3° south and are covered by flat lying Holocene sediments. Focal mechanisms solutions along the western end suggest NW-SE shortening, which is inconsistent with left lateral strain partitioning along the fault zone. The limited deformation of older strata and inconsistent strain partitioning may be explained by a westerly propagation of the fault system from the southwest end. The limited geomorphic structural expression along the North Boqueron Bay Fault segment

Progress report, 1 July 1974--30 June 1975

International Nuclear Information System (INIS)

1975-01-01

Results are reported from field studies on the effects of thermal additions from the Turkey Point nuclear power plant discharge on the macro-invertebrates and fishes of this area of Biscayne Bay. Replicate samples with a 3 m (10 foot) otter trawl lined with .63 mm (4 in.) bar mesh were made monthly at 51 stations. Data on temperature, salinity, and oxygen were collected during each sampling period. Additional chemical data were collected when opportunity existed. The experimental results suggest that maximum summer temperatures above 32 0 C cause detrimental changes in the environment which are reversible in the winter, while temperatures above 33 0 C cause damage which does not recover during the cooler months. Intermittent flow of discharge water is as damaging as constant flow. Card Sound was occupied by a sponge-brittle star community but many organisms were common to both the Sound and Biscayne Bay. The discharge to Card Sound lasted about one year and temperatures in excess of 33 0 C were uncommon. Only a few indicator species showed stress and higher apparent abundance of others offset their decrease. Generally no lasting damage occurred in Card Sound. Recovery after closing Grand Canal was relatively complete 200 yards from the effluent. Data are also included from studies on leaf degeneration in mangrove swamps and the relationship of associated fungi in the decay of leaves of mangrove and other tropical shoreline trees. (U.S.)

A comparative study of the accumulation of metals in the barnacle (Tetraclita serrata and the black mussel (Choromytilis meridionalis in False Bay, South Africa

Directory of Open Access Journals (Sweden)

Adriaan J. Reinecke

2014-02-01

Full Text Available The development of methods to monitor the South African coastal waters offer major challenges. Knowledge and availability of suitable species that may serve as biomonitors will be valuable to obtain information to support good management decisions. It is therefore important to identify local species that show the basic characteristics required for biomonitoring. The aim of this study was to compare, as part of a wider seasonal field study of metals in the intertidal zone of False Bay, South Africa, the body loads of copper (Cu, nickel (Ni, lead (Pb, cadmium (Cd and zinc (Zn in the black mussel (C. meridionalis and the barnacle (T. serrata, and to compare these with environmental concentrations. Also to draw conclusions about the animals’ relative abilities to accumulate priority metals. Specimens of both species were collected over several seasons at different points in False Bay and analysed chemically. The mean body load (soft tissue and shell of metals was higher in the black mussel than in the barnacle during all seasons. A comparison between the body loads and environmental concentrations in water and sediment showed that the priority metals Cd, Ni and Pb are accumulated strongly by both C. meridionalis and T. serrata. The mean Cd body loads varied between 6.43 µg/g and 14.73 µg/g for the various seasons but was not statistically significantly different between seasons. Metal concentrations were in most cases highest during winter. Multiple regression analysis showed a strong correlation between body load of metals in the black mussel and the environmental concentration for most seasons, which indicates that the black mussel can be useful as an active rather than a passive biomonitor. The concept of biomonitoring has merit because it may show long-term tendencies, but it does not offer an absolute measure of immediate, varying pollution levels. It could serve as an additional management tool in a national marine programme for the

77 FR 2972 - Thunder Bay Power Company, Thunder Bay Power, LLC, et al.

Science.gov (United States)

2012-01-20

... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Thunder Bay Power Company, Thunder Bay Power, LLC, et al.; Notice of Application for Transfer of Licenses, and Soliciting Comments and Motions To Intervene Thunder Bay Power Company Project No. 2404-095 Thunder Bay Power, LLC Midwest Hydro, Inc...

Holy grail at Baglan Bay

International Nuclear Information System (INIS)

Watson, Jim

1999-01-01

The UK government's consent for the construction of a gas-fired power plant at Baglan Bay in South Wales is reported, and the growing popularity of economic combined-cycle gas turbine (CCGT) power plants and the resulting environmental improvements are noted . The combining of gas and steam turbines, design developments, and the UK moratorium on planning consents for gas fired power plants are discussed. General Electric's H System technology which will lower the amount of energy lost in the conversion of natural gas to electricity is described, and details of the ten most problematic CCGTs in the UK are given. The domination of the CCGT global market by four manufacturers, and the pressure on manufacturers to develop their designs are considered. (UK)

Yellowfin Tuna (Thunnusalbacares Fishing Ground Forecasting Model Based On Bayes Classifier In The South China Sea

Directory of Open Access Journals (Sweden)

Zhou Wei-feng

2017-08-01

Full Text Available Using the yellowfin tuna (Thunnusalbacares,YFTlongline fishing catch data in the open South China Sea (SCS provided by WCPFC, the optimum interpolation sea surface temperature (OISST from CPC/NOAA and multi-satellites altimetric monthly averaged product sea surface height (SSH released by CNES, eight alternative options based on Bayes classifier were made in this paper according to different strategies on the choice of environment factors and the levels of fishing zones to classify the YFT fishing ground in the open SCS. The classification results were compared with the actual ones for validation and analyzed to know how different plans impact on classification results and precision. The results of validation showed that the precision of the eight options were 71.4%, 75%, 70.8%, 74.4%, 66.7%, 68.5%, 57.7% and 63.7% in sequence, the first to sixth among them above 65% would meet the practical application needs basically. The alternatives which use SST and SSH simultaneously as the environmental factors have higher precision than which only use single SST environmental factor, and the consideration of adding SSH can improve the model precision to a certain extent. The options which use CPUE’s mean ± standard deviation as threshold have higher precision than which use CPUE’s 33.3%-quantile and 66.7%-quantile as the threshold

Petroleum possibilities of the James Bay Lowland area: Drilling in the James Bay Lowland

Energy Technology Data Exchange (ETDEWEB)

Martison, N W

1954-12-31

Interest in the possible occurrence of petroleum and natural gas in the James Bay lowland arises from the presence there of Palaeozoic sedimentary formations resembling those in south-western Ontario. The first part of this report reviews earlier geologic surveys conducted in the lowland and reports results of field work and drill core studies 1946-51. It describes the area`s topography, climate, stratigraphy and palaeontology (Ordovician to Lower Cretaceous, plus Pleistocene and recent glacial deposits), structural geology, and evidence of petroleum. Lists of fossils and correlations are included. The appendices include a list of fossil locations and drill logs. The second part details the drilling programs carried out in the lowland by the Ontario Dept. of Mines, including detailed logs, as well as drilling carried out by some other organisations.

Numerical simulation of hydrodynamic and water quality effects of shoreline changes in Bohai Bay

Science.gov (United States)

Jia, Han; Shen, Yongming; Su, Meirong; Yu, Chunxue

2018-02-01

This study uses the HD and Ecolab modules of MIKE to simulate the hydrodynamic and water quality and predict the influence of shoreline changes in Bohai Bay, China. The study shows that shoreline changes weaken the residual current and generate a counter-clockwise circulation south of Huanghua Port, thereby resulting in weak water exchange capacity and low pollutant-diffusing capacity. Shoreline changes reduce the area of Bohai Bay, resulting in a smaller tidal prism and further weakening the water exchange capacity. This situation is not conducive to the diffusion of pollutants, and therefore may lead to increased water pollution in the bay. Shoreline changes hinder the spread of runoff, weaken the dilution effect of the river on seawater, and block the spread of coastal residual current, thereby resulting in increased salinity near the reclamation area. Shoreline changes lead to an increase in PO4-P concentration and decrease in DIN concentration. The value of N/P near the project decreases, thereby weakening the phosphorus-limited effect.

33 CFR 162.125 - Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Sturgeon Bay and the Sturgeon Bay Ship Canal, Wisc. 162.125 Section 162.125 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY INLAND WATERWAYS NAVIGATION REGULATIONS § 162.125 Sturgeon Bay and the Sturgeon Bay Ship...

Origins of cryptic variation in the Ediacaran-Fortunian rhyolitic ignimbrites of the Saldanha Bay Volcanic Complex, Western Cape, South Africa

Science.gov (United States)

Clemens, J. D.; Stevens, G.; Frei, D.; Joseph, C. S. A.

2017-12-01

The Saldanha eruption centre, on the West Coast of South Africa, consists of 542 Ma, intracaldera, S-type, rhyolite ignimbrites divided into the basal Saldanha Ignimbrite and the partly overlying Jacob's Bay Ignimbrite. Depleted-mantle Nd model ages suggest magma sources younger than the Early Mesoproterozoic, and located within the Neoproterozoic Malmesbury Group and Swartland complex metasedimentary and metavolcanic rocks that form the regional basement. The Sr isotope systematics suggest that the dominant source rocks were metavolcaniclastic rocks and metagreywackes, and that the magmas formed from separate batches extracted from the same heterogeneous source. No apparent magma mixing trends relate the Saldanha to the Jacob's Bay Ignimbrites, or either of these to the magmas that formed the Plankiesbaai or Tsaarsbank Ignimbrites in the neighbouring Postberg eruption centre. The magmas were extracted from their source rocks carrying small but significant proportions of peritectic and restitic accessory minerals. Variations in the content of this entrained crystal cargo were responsible for most of the chemical variations in the magmas. Although we cannot construct a cogent crystal fractionation model to relate these groups of magmas, at least some crystal fractionation occurred, as an overlay on the primary signal due to peritectic assemblage entrainment (PAE). Thus, the causes of the cryptic chemical variation among the ignimbrite magmas of the Saldanha centre are variable, but dominated by the compositions of the parent melts and PAE. The preservation of clear, source-inherited chemical signatures, in individual samples, calls into question the common interpretation of silicic calderas as having been formed in large magma reservoirs, with magma compositions shaped by magma mingling, mixing, and fractional crystallization. The Saldanha rocks suggest a more intimate connection between source and erupted magma, and perhaps indicate that silicic magmas are too

Pb’s high sedimentation inside the bay mouth of Jiaozhou Bay

Science.gov (United States)

Yang, Dongfang; Miao, Zhenqing; Huang, Xinmin; Wei, Linzhen; Feng, Ming

2017-12-01

Sedimentation is one of the key environmental behaviors of pollutants in the ocean. This paper analyzed the seasonal and temporal variations of Pb’s sedimentation process in Jiaozhou Bay in 1987. Results showed that Pb contents in bottom waters in Jiaozhou Bay in May, July and November 1987 were 1.87-2.60 μg L-1, 15.11-19.68 μg L-1 and 11.08-15.18 μg L-1, and the pollution levels of Pb in May, July and November 1987 were slight, heavy and heavy, respectively. In May 1987, there was low sedimentation process in waters in the outside of the bay mouth, yet were high sedimentation process in waters in the middle and inside of the bay mouth. In July and November 1987, there was low sedimentation process in waters in the outside of the bay mouth, yet were high sedimentation process in waters in the inside of the bay mouth. The seasonal-temporal variation of sedimentation processes of Pb were determined by the variations of sources input and the vertical water’s effect.

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...

HEAVY METAL CONTENTS IN MARINE SEDIMENTS AND SEAWATER AT TOTOK BAY AREA, NORTH SULAWESI

Directory of Open Access Journals (Sweden)

Delyuzar Ilahude

2017-07-01

Full Text Available The study area is located in north-eastern part of Tomini Bay, approximately 80 km south of Manado city, North Sulawesi. This area is closed to submarine tailing disposal system in Buyat Bay. Five marine sediment samples and four water samples from seawater and dig wells have been used for heavy metals (Hg, As, CN analyses by using Atomic Absorption Spectrometry (AAS. This study is a part of research conducted by Marine Geological Institute of Indonesia on morphological changes of seabed in the Totok Bay. The result shows that concentration of mercury (Hg in water samples taken from Ratatotok estuary is higher than standards stipulated Government Regulation (Peraturan Pemerintah/PP No. 82/2001. Meanwhile, concentration of arsenic (As is almost reaching its standard threshold, and conversely cyanide (CN concentration is low. This value of mercury (Hg concentration taken from Ratatotok estuary is much higher than water samples from of Buyat Bay estuary. Significant concentration of mercury (Hg analysed from those particular sampling sites indicated high mercury contamination. Therefore, further examination on ground water of dig wells is necessary, especially for mercury analysis (Hg. Furthermore, comparing the formerly obtained data of mercury concentration in the sediment, this particular study concludes that the sediments in the Totok Bay had contaminated by mercury from gold-processing of illegal mining.

Coastal currents and mass transport of surface sediments over the shelf regions of Monterey Bay, California

Science.gov (United States)

Wolf, S.C.

1970-01-01

In Monterey Bay, the highest concentrations of medium and fine sands occur nearshore between ten and thirty fathoms. Silt and clay accumulate in greater depths. Contours of median diameter roughly parallel the isobaths. Fine-grained materials are supplied to the bay region from erosion of cliffs which partly surround Monterey Bay, from sediment laden river discharge, and from continual reworking of widespread Pleistocene and Recent sea floor sediments. These sediments in turn are picked up by coastal currents and distributed over the shelf regions by present day current regimes. Studies of bottom currents over the shelf regions and in Monterey Canyon have revealed patterns which vary with seasonal changes. Current patterns during August and September exhibit remarkable symmetry about the axis of Monterey Submarine Canyon. Central Shelf currents north and south of Monterey Canyon flowed northwest at an average rate of 0.2 knots and south at 0.3 knots respectively. On the North Shelf between January and March currents flowed east to southeast at 0.3-0.5 knots with mirror image patterns above the South Shelf during the same period. Irregular current flow in the canyon indicates a complex current structure with frequent shifts in counterclockwise and clockwise direction over very short periods of time. Bottom topography of the canyon complex often causes localization of canyon currents. One particular observation at a depth of 51 fathoms indicated up-canyon flow at a rate of 0.2 knots. Most of the observed currents are related to seasonal variations, upwelling, ocean swell patterns, and to changes in the California and Davidson currents. Changes in current regimes are reflected in the patterns of sediment distribution and transport. Sediment transport is chiefly parallel to the isobaths, particularly on the North and South Shelf regions. Complex dispersal patterns are observed near Monterey Canyon and Moss Landing Harbor jetties. Longshore currents move sediments

Geochemical evidence for groundwater behavior in an unconfined aquifer, south Florida

Science.gov (United States)

Meyers, Jayson B.; Swart, Peter K.; Meyers', Janet L.

1993-07-01

Five well sites have been investigated along an east-west transect across the surfical aquifer system (SAS) of south Florida. Differences between rainfall during wet seasons (June-October) and evaporation during dry seasons (November-May) give surface waters of this region isotopically light ( δ 18O -22‰ and δ D -7.6‰ ) and heavy ( δ 18O +4.2‰ ) compositions, respectively. Surface waters and shallow groundwaters are enriched in 18O and D to the west, which is consistent with westward decrease in equal excess of rainfall. In the shallow portion of the SAS (less than 20 m, Biscayne sub-aquifer) heterogeneous stable isotopic compositions occur over short spans of time (less than 90 days), reflecting seasonal changes in the isotopic composition of recharge and rapid flushing. Homogeneous stable isotopic compositions occur below the Biscayne sub-aquifer, marking the zone of delayed circulation. Surface evaporation calculated from a stable isotope evaporation model agrees with previously published estimates of 75-95% by physical evaporation measurements and water budget calculations. This model contains many parameters that are assumed to be mean values, but short-term variability in some of these parameters may make this model unsuitable for the application of yearly mean values. For the Everglades, changes in the isotopic composition of atmospheric vapor during the dry season may cause the model to yield anomalous results when annual mean values are used. Chloride-enriched waters (more than 280 mg 1 -1) form a plume emanating from the bottom central portion of the transect. Elevated chloride concentration and light stable isotopic composition ( δ 18O ≈ -2‰ , δ D ≈ -8‰ ) suggest this plume is probably caused not by salinity of residual seawater in the aquifer, but by leakage from the minor artesian water-bearing zone of the Floridan aquifer system. Stable isotope values from Floridan aquifer groundwater plot close to the meteoric water line, in the

South Oregon Coast Reinforcement.

Energy Technology Data Exchange (ETDEWEB)

United States. Bonneville Power Administration.

1998-05-01

The Bonneville Power Administration is proposing to build a transmission line to reinforce electrical service to the southern coast of Oregon. This FYI outlines the proposal, tells how one can learn more, and how one can share ideas and opinions. The project will reinforce Oregon`s south coast area and provide the necessary transmission for Nucor Corporation to build a new steel mill in the Coos Bay/North Bend area. The proposed plant, which would use mostly recycled scrap metal, would produce rolled steel products. The plant would require a large amount of electrical power to run the furnace used in its steel-making process. In addition to the potential steel mill, electrical loads in the south Oregon coast area are expected to continue to grow.

Integrating Salmon Recovery, Clean Water Act Compliance, Restoration, and Climate Change Impacts in the South Fork Nooksack River

Science.gov (United States)

"The South Fork Nooksack River (SFNR) is an important tributary to the Nooksack River, Bellingham Bay, and the Salish Sea. The South Fork Nooksack River comprises one of the 22 independent populations of spring Chinook in the Puget Sound Chinook Evolutionarily Significant Un...

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

Hurricane-induced Sediment Transport and Morphological Change in Jamaica Bay, New York

Science.gov (United States)

Hu, K.; Chen, Q. J.

2016-02-01

Jamaica Bay is located in Brooklyn and Queens, New York on the western end of the south shore of the Long Island land mass. It experienced a conversion of more than 60% of the vegetated salt-marsh islands to intertidal and subtidal mudflats. Hurricanes and nor'easters are among the important driving forces that reshape coastal landscape quickly and affect wetland sustainability. Wetland protection and restoration need a better understanding of hydrodynamics and sediment transport in this area, especially under extreme weather conditions. Hurricane Sandy, which made landfall along east coast on October 30, 2012, provides a critical opportunity for studying the impacts of hurricanes on sedimentation, erosion and morphological changes in Jamaica Bay and salt marsh islands. The Delft3D model suit was applied to model hydrodynamics and sediment transport in Jamaica Bay and salt marsh islands. Three domains were set up for nesting computation. The local domain covering the bay and salt marshes has a resolution of 10 m. The wave module was online coupled with the flow module. Vegetation effects were considered as a large number of rigid cylinders by a sub-module in Delft3D. Parameters in sediment transport and morphological change were carefully chosen and calibrated. Prior- and post-Sandy Surface Elevation Table (SET)/accretion data including mark horizon (short-term) and 137Cs and 210Pb (long-term) at salt marsh islands in Jamaica Bay were used for model validation. Model results indicate that waves played an important role in hurricane-induced morphological change in Jamaica Bay and wetlands. In addition, numerical experiments were carried out to investigate the impacts of hypothetic hurricanes. This study has been supported by the U.S. Geological Survey Hurricane Sandy Disaster Recovery Act Funds.

Modeling the climatic and subsurface stratigraphy controls on the hydrology of a Carolina bay wetland in South Carolina, USA

Science.gov (United States)

Ge Sun; Timothy J. Callahan; Jennifer E. Pyzoha; Carl C. Trettin

2006-01-01

Restoring depressional wetlands or geographically isolated wetlands such as cypress swamps and Carolina bays on the Atlantic Coastal Plains requires a clear understanding of the hydrologic processes and water balances. The objectives of this paper are to (1) test a distributed forest hydrology model, FLATWOODS, for a Carolina bay wetland system using seven years of...

Modeling the climatic and subsurface stratigraphy controls on the hydrology of a Carolina Bay wetland in South Carolina, USA

Science.gov (United States)

Ge Sun; Timothy J. Callahan; Jennifer E. Pyzoha; Carl C. Trettin

2006-01-01

Restoring depressional wetlands or geographically isolated wetlands such as cypress swamps and Carolina bays on the Atlantic Coastal Plains requires a clear understanding of the hydrologic processes and water balances. The objectives of this paper are to (1) test a distributed forest hydrology model, FLATWOODS, for a Carolina bay wetland system using seven years of...

Geneva University: Observation of electron-antineutrino disappearance at Daya Bay

CERN Multimedia

Université de Genève

2012-01-01

GENEVA UNIVERSITY École de physique Département de physique nucléaire et corspusculaire 24, quai Ernest-Ansermet 1211 Genève 4 Tél.: (022) 379 62 73 Fax: (022) 379 69 92 Monday 19 March 2012 COLLOQUE DE PHYSIQUE 5 p.m. - École de Physique, Auditoire Stueckelberg Observation of electron-antineutrino disappearance at Daya Bay  Professor Yifang Wang Institute of High Energy Physics of the Chinese Academy of Sciences Beijing The Daya Bay Reactor Neutrino Experiment, a multinational collaboration operating in the south of China, today reported the first results of its search for the last, most elusive piece of a long-standing puzzle: how is it that neutrinos can appear to vanish as they travel? The surprising answer opens a gateway to a new understanding of fundamental physics and may eventually solve the riddle of why there is far more ordinary matter than antimatter in the Universe today....

Spatial distribution of heavy metals in surficial sediments from Guanabara Bay: Rio de Janeiro, Brazil

Science.gov (United States)

Neto, José Antônio Baptista; Gingele, Franz Xaver; Leipe, Thomas; Brehme, Isa

2006-04-01

Ninety-two surface sediment samples were collected in Guanabara Bay, one of the most prominent urban bays in SE Brazil, to investigate the spatial distribution of anthropogenic pollutants. The concentrations of heavy metals, organic carbon and particle size were examined in all samples. Large spatial variations of heavy metals and particle size were observed. The highest concentrations of heavy metals were found in the muddy sediments from the north western region of the bay near the main outlets of the most polluted rivers, municipal waste drainage systems and one of the major oil refineries. Another anomalous concentration of metals was found adjacent to Rio de Janeiro Harbour. The heavy metal concentrations decrease to the northeast, due to intact rivers and the mangrove systems in this area, and to the south where the sand fraction and open-marine processes dominate. The geochemical normalization of metal data to Li or Al has also demonstrated that the anthropogenic input of heavy metals have altered the natural sediment heavy metal distribution.

Radionuclides in the ecological system of the Boka Kotorska Bay

International Nuclear Information System (INIS)

Martic, M.; Ajdacic, N.

1988-01-01

In order to determine radioactive contamination in the South Adriatic region after May, 1986, activities of 21 radionuclides of natural and artificial origin were determined by gamma-spectrometry in the samples of sea water, sediments and several characteristic types of organisms collected on several locations in the Boka Kotorska Bay and open sea. Quantitative data on radionuclide contents are presented. Change of activity levels with respect to the 'zero state' determined for this region during previous years is also discussed. (author) 6 refs.; 4 tabs

Generation of deterministic tsunami hazard maps in the Bay of Cadiz, south-west Spain

Science.gov (United States)

Álvarez-Gómez, J. A.; Otero, L.; Olabarrieta, M.; González, M.; Carreño, E.; Baptista, M. A.; Miranda, J. M.; Medina, R.; Lima, V.

2009-04-01

The bay of Cádiz is a densely populated and industrialized area, and an important centre of tourism which multiplies its population in the summer months. This bay is situated in the Gulf of Cádiz, the south-west Atlantic margin of the Iberian Peninsula. From a tectonic point of view this area can be defined as a diffuse plate boundary, comprising the eastern edge of the Gloria and Tydeman transforms (where the deformation is mainly concentrated in these shear corridors), the Gorringe Bank, the Horseshoe Abyssal plain, the Portimao and Guadalquivir banks, and the western termination of the arcuated Gibraltar Arc. This deformation zone is the eastern edge of the Azores - Gibraltar seismic zone, being the present day boundary between the Eurasian and African plates. The motion between the plates is mainly convergent in the Gulf of Cádiz, but gradually changes to almost pure transcurrent along the Gloria Fault. The relative motion between the two plates is of the order of 4-5 mm/yr. In order to define the different tsunamigenic zones and to characterize its worst tsunamigenic source we have used seismic, structural and geological data. The numerical model used to simulate the wave propagation and coastal inundation is the C3 (Cantabria, COMCOT and Tsunami-Claw) model. C3 is a hybrid finite difference-finite volume method which balances between efficiency and accuracy. For offshore domain in deep waters the model applies an explicit finite difference scheme (FD), which is computationally fast and accurate in large grids. For near coast domains in coastal areas, it applies a finite volume scheme (VOF). It solves correctly the bore formation and the bore propagation. It is very effective solving the run-up and the run down. A set of five worst case tsunamigenic sources has been used with four different sea levels (minimum tide, most probable low tide, most probable high tide and maximum tide), in order to produce the following thematic maps with the C3 model: maximum

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

The Tsunami Geology of the Bay of Bengal Shores and the Predecessors of the 2004 Indian Ocean Event

Science.gov (United States)

Rajendran, C.; Rajendran, K.; Seshachalam, S.; Andrade, V.

2010-12-01

The 2004 Aceh-Andaman earthquake exceeded the known Indian Ocean precedents by its 1,300-km long fault rupture and the height and reach of its tsunami. Literature of the ancient Chola dynasty (AD 9-11 centuries) of south India and the archeological excavations allude to a sea flood that crippled the historic port at Kaveripattinam, a trading hub for Southeast Asia. Here, we combine a variety of data from the rupture zone as well as the distant shores to build a tsunami history of the Bay of Bengal. A compelling set of geological proxies of possible tsunami inundation include boulder beds of Car Nicobar Island in the south and the East Island in the northernmost Andaman, a subsided fossil mangrove forest near Port Blair and a washover sedimentation identified in the Kaveripattinam coast of Tamil Nadu, south India. We have developed an extensive chronology for these geological proxies, and we analyze them in conjunction with the historical information culled from different sources for major sea surges along the Bay of Bengal shores. The age data and the depositional characteristics of these geological proxies suggest four major tsunamis in the last 2000 years in the Bay of Bengal, including the 1881 Car Nicobar tsunami. Among these, the evidence for the event of 800-1200 cal yr BP is fairly well represented on both sides of the Bay of Bengal shores. Thus, we surmise that the 800-1000-year old tsunami mimics the transoceanic reach of the 2004 Indian Ocean and the age constraints also agree with the sea surge during the Chola period. We also obtained clues for a possible medieval tsunami from the islands occurred probably a few hundred years after the Chola tsunami, but its size cannot constrained, nor its source. The convergence of ages and the multiplicity of sites would suggest at least one full size predecessor of the 2004 event 1000-800 years ago.

Concentrations of metals in blood and feathers of nestling ospreys (Pandion haliaetus) in Chesapeake and Delaware Bays

Science.gov (United States)

Rattner, B.A.; Golden, N.H.; Toschik, P.C.; McGowan, P.C.; Custer, T.W.

2008-01-01

In 2000, 2001, and 2002, blood and feather samples were collected from 40-45-day-old nestling ospreys (Pandion haliaetus) from Chesapeake Bay and Delaware Bay and River. Concentrations of 18 metals, metalloids, and other elements were determined in these samples by inductively coupled plasma-mass spectroscopy, and Hg concentrations were measured by cold vapor atomic absorption spectroscopy. When compared to concurrent reference areas (South, West, and Rhode Rivers), mean As and Hg concentrations in blood were greater (p nestlings from the highly industrialized Elizabeth River compared to the rural reference area. When compared to the concurrent reference area, mean Al, Ba, Hg, Mn, and Pb concentrations in feathers were substantially greater (p nestlings from northern Delaware Bay and River had greater concentrations (p nestling feathers from Delaware were frequently greater than in the Chesapeake. The present findings and those of related reproductive studies suggest that concentrations of several heavy metals (e.g., Cd, Hg, Pb) in nestling blood and feathers from Chesapeake and Delaware Bays were below toxicity thresholds and do not seem to be affecting chick survival during the nestling period.

A Holocene progradation record from Okains Bay, Banks Peninsula, Canterbury, New Zealand

International Nuclear Information System (INIS)

Stephenson, W.; Shulmeister, J.

1999-01-01

Fifty-eight distinct ridges are preserved on the Holocene progradation plain in Okains Bay, Banks Peninsula, Canterbury. Of these, 48 represent beach berm and foredune complexes and the remaining 10 are transverse dune ridges. Periods of rapid coastal progradation are marked by multiple beach berm preservation, whereas intervening periods of lower sediment accumulation result in a stable coastline and transverse dune formation. Infilling of the bay began following sea-level stabilisation in the mid Holocene. The fill is dominantly fine sand, which is derived from sediment carried around Banks Peninsula in the Southland Current and washed into Okains Bay by wave action. Variations in the progradation rate are therefore proxy indicators of coastal erosion in the Canterbury Bight. We demonstrate that there is little progradational fill preserved between c. 6500 and 2000 yr BP. This implies significant changes in sediment delivery to the Southland Current within the last 2000 yr, which we attribute to increased coastal erosion in South Canterbury. We speculate that this increasing erosion resulted from increased wave energy regimes, which in turn may relate to increasing Southern Hemisphere seasonality following the precessional cycle. (author). 32 refs., 4 figs., 3 tabs

Evidence for the existence of Persian Gulf Water and Red Sea Water in the Bay of Bengal

Science.gov (United States)

Jain, Vineet; Shankar, D.; Vinayachandran, P. N.; Kankonkar, A.; Chatterjee, Abhisek; Amol, P.; Almeida, A. M.; Michael, G. S.; Mukherjee, A.; Chatterjee, Meenakshi; Fernandes, R.; Luis, R.; Kamble, Amol; Hegde, A. K.; Chatterjee, Siddhartha; Das, Umasankar; Neema, C. P.

2017-05-01

The high-salinity water masses that originate in the North Indian Ocean are Arabian Sea High-Salinity Water (ASHSW), Persian Gulf Water (PGW), and Red Sea Water (RSW). Among them, only ASHSW has been shown to exist in the Bay of Bengal. We use CTD data from recent cruises to show that PGW and RSW also exist in the bay. The presence of RSW is marked by a deviation of the salinity vertical profile from a fitted curve at depths ranging from 500 to 1000 m; this deviation, though small (of the order of 0.005 psu and therefore comparable to the CTD accuracy of 0.003 psu), is an order of magnitude larger than the 0.0003 psu fluctuations associated with the background turbulence or instrument noise in this depth regime, allowing us to infer 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. This salinity minimum and the maximum associated with ASHSW disappear east and north of the south-central bay (85°E, 8°N) owing to mixing between the fresher surface waters that are native to the bay (Bay of Bengal Water or BBW) with the high-salinity ASHSW. Hence, ASHSW is not seen as a distinct water mass in the northern and eastern bay and the maximum salinity over most of the bay is associated with PGW. The surface water over most of the bay is therefore a mixture of ASHSW and the low-salinity BBW. As a corollary, we can also infer that the weak oxygen peak seen within the oxygen-minimum zone in the bay at a depth of 250-400 m is associated with PGW. The hydrographic data also show that these three high-salinity water masses are advected into the bay by the Summer Monsoon Current, which is seen to be a deep current extending to 1000 m. These deep currents extend into the northern bay as well, providing a mechanism for spreading ASHSW, PGW, and RSW throughout the bay.

33 CFR 334.1320 - Kuluk Bay, Adak, Alaska; naval restricted area.

Science.gov (United States)

2010-07-01

... THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1320 Kuluk Bay, Adak...: Beginning on shore at latitude 51°55′00″ N, longitude 176°33′09″ W; thence due east to latitude 51°55′00″ N, longitude 176°33′09″ W; thence due south to latitude 51°51′55″ N longitude 176°31′09″ W; thence due west to...

226Ra behavior in the Pee Dee river-Winyah Bay estuary

International Nuclear Information System (INIS)

Elsinger, R.J.; Moore, W.S.

1980-01-01

Concentrations of dissolved 226 Ra in Winyah Bay, South Carolina, and in the adjacent Atlantic Ocean are augmented by the desorption of radium from sediments in the low-salinity area of the estuary and diffusion from bottom sediments. Desorption of 226 Ra is reflected by lower concentrations in suspended sediments from higher-salinity regions of the estuary. Bottom sediments from the high-salinity region have lower 226 Ra/ 230 Th activity ratios than those from the low-salinity end. (orig./ME)

Evolution of extreme high waters along the east coast of India and at the head of the Bay of Bengal

Digital Repository Service at National Institute of Oceanography (India)

Antony, C.; Unnikrishnan, A.S.; Woodworth, P.L.

. The highest water levels above mean sea level have the greatest magnitude towards the northern part of the Bay, which decreases towards its south-west. Extreme high waters were observed to result from a combination of moderate, or even small, surges with large...

75 FR 8297 - Tongass National Forest, Thorne Bay Ranger District, Thorne Bay, AK

Science.gov (United States)

2010-02-24

..., Thorne Bay, AK AGENCY: Forest Service, USDA. ACTION: Cancellation of Notice of intent to prepare an... Roberts, Zone Planner, Thorne Bay Ranger District, Tongass National Forest, P.O. Box 19001, Thorne Bay, AK 99919, telephone: 907-828-3250. SUPPLEMENTARY INFORMATION: The 47,007-acre Kosciusko Project Area is...

77 FR 44140 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

Science.gov (United States)

2012-07-27

... Maple-Oregon Bridges so vehicular traffic congestion would not develop on downtown Sturgeon Bay streets... movement of vehicular traffic in Sturgeon Bay. The Sturgeon Bay Ship Canal is approximately 8.6 miles long... significant increase in vehicular and vessel traffic during the peak tourist and navigation season between...

Physical processes in a coupled bay-estuary coastal system: Whitsand Bay and Plymouth Sound

Science.gov (United States)

Uncles, R. J.; Stephens, J. A.; Harris, C.

2015-09-01

Whitsand Bay and Plymouth Sound are located in the southwest of England. The Bay and Sound are separated by the ∼2-3 km-wide Rame Peninsula and connected by ∼10-20 m-deep English Channel waters. Results are presented from measurements of waves and currents, drogue tracking, surveys of salinity, temperature and turbidity during stratified and unstratified conditions, and bed sediment surveys. 2D and 3D hydrodynamic models are used to explore the generation of tidally- and wind-driven residual currents, flow separation and the formation of the Rame eddy, and the coupling between the Bay and the Sound. Tidal currents flow around the Rame Peninsula from the Sound to the Bay between approximately 3 h before to 2 h after low water and form a transport path between them that conveys lower salinity, higher turbidity waters from the Sound to the Bay. These waters are then transported into the Bay as part of the Bay-mouth limb of the Rame eddy and subsequently conveyed to the near-shore, east-going limb and re-circulated back towards Rame Head. The Simpson-Hunter stratification parameter indicates that much of the Sound and Bay are likely to stratify thermally during summer months. Temperature stratification in both is pronounced during summer and is largely determined by coastal, deeper-water stratification offshore. Small tidal stresses in the Bay are unable to move bed sediment of the observed sizes. However, the Bay and Sound are subjected to large waves that are capable of driving a substantial bed-load sediment transport. Measurements show relatively low levels of turbidity, but these respond rapidly to, and have a strong correlation with, wave height.

Lateral variation in crustal and mantle structure in Bay of Bengal based on surface wave data

Science.gov (United States)

Kumar, Amit; Mukhopadhyay, Sagarika; Kumar, Naresh; Baidya, P. R.

2018-01-01

Surface waves generated by earthquakes that occurred near Sumatra, Andaman-Nicobar Island chain and Sunda arc are used to estimate crustal and upper mantle S wave velocity structure of Bay of Bengal. Records of these seismic events at various stations located along the eastern coast of India and a few stations in the north eastern part of India are selected for such analysis. These stations lie within regional distance of the selected earthquakes. The selected events are shallow focused with magnitude greater than 5.5. Data of 65, 37, 36, 53 and 36 events recorded at Shillong, Bokaro, Visakhapatnam, Chennai and Trivandrum stations respectively are used for this purpose. The ray paths from the earthquake source to the recording stations cover different parts of the Bay of Bengal. Multiple Filtering Technique (MFT) is applied to compute the group velocities of surface waves from the available data. The dispersion curves thus obtained for this data set are within the period range of 15-120 s. Joint inversion of Rayleigh and Love wave group velocity is carried out to obtain the subsurface information in terms of variation of S wave velocity with depth. The estimated S wave velocity at a given depth and layer thickness can be considered to be an average value for the entire path covered by the corresponding ray paths. However, we observe variation in the value of S wave velocity and layer thickness from data recorded at different stations, indicating lateral variation in these two parameters. Thick deposition of sediments is observed along the paths followed by surface waves to Shillong and Bokaro stations. Sediment thickness keeps on decreasing as the surface wave paths move further south. Based on velocity variation the sedimentary layer is further divided in to three parts; on top lay unconsolidated sediment, underlain by consolidated sediment. Below this lies a layer which we consider as meta-sediments. The thickness and velocity of these layers decrease from north

75 FR 16745 - Endangered and Threatened Species; 90-Day Finding on a Petition to Delist Coho Salmon South of...

Science.gov (United States)

2010-04-02

... Salmon South of San Francisco Bay AGENCY: National Marine Fisheries Service (NMFS), National Oceanic and... delist coho salmon (Oncorhynchus kisutch) in coastal counties south of the ocean entrance to San... Species Act (ESA) of 1973, as amended. Coho salmon populations in this region are currently listed under...

76 FR 6383 - Endangered and Threatened Species; 12-Month Finding on a Petition To Delist Coho Salmon South of...

Science.gov (United States)

2011-02-04

... Coho Salmon South of San Francisco Bay AGENCY: National Marine Fisheries Service (NMFS), National... finding on a petition to delist coho salmon (Oncorhynchus kisutch) in coastal counties south of the ocean... the Endangered Species Act (ESA) of 1973, as amended. Coho salmon populations in this region are...

78 FR 46813 - Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI

Science.gov (United States)

2013-08-02

...-AA00 Safety Zone; Evening on the Bay Fireworks; Sturgeon Bay, WI AGENCY: Coast Guard, DHS. ACTION.... This temporary safety zone will restrict vessels from a portion of Sturgeon Bay due to a fireworks... hazards associated with the fireworks display. DATES: This rule is effective from 8 p.m. until 10 p.m. on...

Hydrographic data report: south coast of Puerto Rico, 1973--1974

International Nuclear Information System (INIS)

Wood, E.D.; Asencio, R.

1975-01-01

The hydrographic data included in this report were collected as part of a site selection survey to provide basic oceanographic data to assist the Puerto Rico Water Resources Authority (PRWRA) in determining the best locations for additional electrical power generating facilities on the island, both nuclear and fossil fuel. This report includes data from two sites and an offshore transect between the sites. The Punta Verraco site, PVE, is on the west side of Guayanilla Bay and the Cabo Mala Pascua site, CMP, is located on the southeast corner of the island. Data were also collected seaward from Jobos Bay, OJB, to determine the effects of the open sea on nearshore oceanographic parameter characteristics. The two south coast sites are about 90 kilometers apart. The offshore Jobos Bay transect was made about 25 kilometers west of Cabo Mala Pascua. (auth)

77 FR 38488 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY

Science.gov (United States)

2012-06-28

... 1625-AA00 Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY... restrict vessels from a portion of the St. Lawrence River during the Alexandria Bay Chamber of Commerce... of proposed rulemaking (NPRM) entitled Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence...

Coastal circulation and sediment dynamics in Maunalua Bay, Oahu, Hawaii, measurements of waves, currents, temperature, salinity, and turbidity; November 2008-February 2009

Science.gov (United States)

Storlazzi, Curt D.; Presto, M. Katherine; Logan, Joshua B.; Field, Michael E.

2010-01-01

High-resolution measurements of waves, currents, water levels, temperature, salinity and turbidity were made in Maunalua Bay, southern Oahu, Hawaii, during the 2008-2009 winter to better understand coastal circulation, water-column properties, and sediment dynamics during a range of conditions (trade winds, kona storms, relaxation of trade winds, and south swells). A series of bottom-mounted instrument packages were deployed in water depths of 20 m or less to collect long-term, high-resolution measurements of waves, currents, water levels, temperature, salinity, and turbidity. These data were supplemented with a series of profiles through the water column to characterize the vertical and spatial variability in water-column properties within the bay. These measurements support the ongoing process studies being done as part of the U.S. Geological Survey (USGS) Coastal and Marine Geology Program's Pacific Coral Reef Project; the ultimate goal of these studies is to better understand the transport mechanisms of sediment, larvae, pollutants, and other particles in coral reef settings. Project Objectives The objective of this study was to understand the temporal variations in currents, waves, tides, temperature, salinity and turbidity within a coral-lined embayment that receives periodic discharges of freshwater and sediment from multiple terrestrial sources in the Maunalua Bay. Instrument packages were deployed for a three-month period during the 2008-2009 winter and a series of vertical profiles were collected in November 2008, and again in February 2009, to characterize water-column properties within the bay. Measurements of flow and water-column properties in Maunalua Bay provided insight into the potential fate of terrestrial sediment, nutrient, or contaminant delivered to the marine environment and coral larval transport within the embayment. Such data are useful for providing baseline information for future watershed decisions and for establishing guidelines for

A sediment budget for the southern reach in San Francisco Bay, CA: Implications for habitat restoration

Science.gov (United States)

Shellenbarger, Gregory; Wright, Scott A.; Schoellhamer, David H.

2013-01-01

The South Bay Salt Pond Restoration Project is overseeing the restoration of about 6000 ha of former commercial salt-evaporation ponds to tidal marsh and managed wetlands in the southern reach of San Francisco Bay (SFB). As a result of regional groundwater overdrafts prior to the 1970s, parts of the project area have subsided below sea-level and will require between 29 and 45 million m3 of sediment to raise the surface of the subsided areas to elevations appropriate for tidal marsh colonization and development. Therefore, a sufficient sediment supply to the far south SFB subembayment is a critical variable for achieving restoration goals. Although both major tributaries to far south SFB have been seasonally gaged for sediment since 2004, the sediment flux at the Dumbarton Narrows, the bayward boundary of far south SFB, has not been quantified until recently. Using daily suspended-sediment flux data from the gages on Guadalupe River and Coyote Creek, combined with continuous suspended-sediment flux data at Dumbarton Narrows, we computed a sediment budget for far south SFB during Water Years 2009–2011. A Monte Carlo approach was used to quantify the uncertainty of the flux estimates. The sediment flux past Dumbarton Narrows from the north dominates the input to the subembayment. However, environmental conditions in the spring can dramatically influence the direction of springtime flux, which appears to be a dominant influence on the net annual flux. It is estimated that up to several millennia may be required for natural tributary sediments to fill the accommodation space of the subsided former salt ponds, whereas supply from the rest of the bay could fill the space in several centuries. Uncertainty in the measurement of sediment flux is large, in part because small suspended-sediment concentration differences between flood and ebb tides can lead to large differences in total mass exchange. Using Monte Carlo simulations to estimate the random error associated with

Hydrographic features of the western Bay of Bengal in the upper 500 m under the influence of NE and SW monsoon

Digital Repository Service at National Institute of Oceanography (India)

Suryanarayana, A.; Murty, V.S.N.; Sarma, Y.V.B.; Babu, M.T.; Rao, D.P.; Sastry, J.S.

considerable variation in space from season to season. The variations are mainly influencEd. by the seasonal winds and fresh water discharge from major rivers located all along the periphery of the Bay. The near surface flow is mainly south westerly during NE...

Gas exchange rates across the sediment-water andd air-water interfaces in south San Francisco Bay

International Nuclear Information System (INIS)

Hartman, B.; Hammond, D.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 uncertainity of the determinations, about 20%. The annual average of bethic 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 inteface 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

Acoustic Doppler velocimeter backscatter for quantification of suspended sediment concentration in South San Francisco Bay, USA

Science.gov (United States)

Öztürk, Mehmet; Work, Paul A.

2016-01-01

A data set was acquired on a shallow mudflat in south San Francisco Bay that featured simultaneous, co-located optical and acoustic sensors for subsequent estimation of suspended sediment concentrations (SSC). The optical turbidity sensor output was converted to SSC via an empirical relation derived at a nearby site using bottle sample estimates of SSC. The acoustic data was obtained using an acoustic Doppler velocimeter. Backscatter and noise were combined to develop another empirical relation between the optical estimates of SSC and the relative backscatter from the acoustic velocimeter. The optical and acoustic approaches both reproduced similar general trends in the data and have merit. Some seasonal variation in the dataset was evident, with the two methods differing by greater or lesser amounts depending on which portion of the record was examined. It is hypothesized that this is the result of flocculation, affecting the two signals by different degrees, and that the significance or mechanism of the flocculation has some seasonal variability. In the earlier portion of the record (March), there is a clear difference that appears in the acoustic approach between ebb and flood periods, and this is not evident later in the record (May). The acoustic method has promise but it appears that characteristics of flocs that form and break apart may need to be accounted for to improve the power of the method. This may also be true of the optical method: both methods involve assuming that the sediment characteristics (size, size distribution, and shape) are constant.

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.

The fouling serpulids (Polychaeta: Serpulidae from United States coastal waters: an overview

Directory of Open Access Journals (Sweden)

J. Rolando Bastida-Zavala

2017-08-01

minutus from Veracruz, Mexico to Pensacola Bay, Florida. The following additional species range extensions are provisional in that they represent only one record or were not found in the most recent surveys (e.g., Hydroides elegans - east coast: H. longispinosa from Marshall Islands to Oahu, Hawaii; Protula balboensis from Florida to Texas; P. longiseta from the Mexican Caribbean to the Indian River, Florida; H. elegans from San Francisco to Humboldt Bay, northern California and on the east coast from the Indian River, Florida, to Cape Cod, Massachusetts. Among surveyed bays, Biscayne Bay, Florida and Corpus Christi, Texas (northern Gulf of Mexico had the greatest number of species (14 and 8, respectively; in contrast, almost all sites in Alaska, Washington, Oregon (northwest Pacific, Rhode Island, Virginia and South Carolina (Atlantic had only one or two species each. Hydroides dianthus was, by far, the most abundant serpulid species on fouling plates in the northern Gulf of Mexico and the east coast, while Pseudochitinopoma occidentalis was the most abundant serpulid detected on the west coast. For each species recorded herein, we include the synonyms and some key references, a material studied section, a diagnosis, and updated distributional information. A checklist and identification key to the known shallow-water serpulids sensu stricto of the United States are included.

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

International Nuclear Information System (INIS)

Suarez-Antola, Roberto

2013-01-01

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, jointly with other

Morphological changes within Florida Bay as a result of sea level rise

Science.gov (United States)

Holmes, C. W.

2011-12-01

Data from Florida Bay indicates that from 10,000 year BP to 6000 BP, the rate of sea level rise averaged about 10 mm/yr. The rate slowed at the end of this period flooding the shallow shelves surrounding the reef platforms of the western Atlantic. The relative flat South Florida shelf, because of its slight tilt to the southwest is an ideal local to assess the effects of this flooding. From 6000 BP to the present, numerous banks were formed within Florida Bay. A morphological model of bank formation based on the sea level oscillations was constructed from analysis of over 120 cores. These cores record sedimentological changes which are correlated to climatic events. In the central bay, the sediment accumulation was controlled by variations in rate of progressive sea-level rise. The Key West sea-level record shows that sea level has been rising incrementally over the last century. Between 1931 and 1950, sea level rose at a rate of 5 mm/yr. After 1950, it remained stable until 1971, when it again began to rise, but at a rate of 3 mm/yr. On the leeward side of mud banks, these variations resulted in shifts in sediment- accumulation rates, with accretion increasing during rising sea level and decreasing during stable periods. Between late 1970 and early 1972, a sharp jump in sea-level rise occurred that was approximately 10 cm higher than the preceding period. This jump coincided with a strongly positive North Atlantic Oscillation (NAO), a la Niña (negative ENSO), and a negative Pacific Decadal Oscillation (PDO). Water driven northward into Florida Bay eroded banks along the northern coastline, increased sediment accumulation in the northern lakes, and increased accretion rates on the banks. In addition to the sedimentological variations in the central portion of the bay, there was significant changes along the northern fringe. Around 1950, the northern fringe of the bay morphed from a fresh water environment to a marine environment. As a result, carbonate production

Assessment of the mobility of metals and semi-metals in Sepetiba Bay (Rio de Janeiro - Brazil) by analyzing sediments sampled in different periods

International Nuclear Information System (INIS)

Cortez, Vinicius D.; Ribeiro, Andreza P.; Figueiredo, Ana M.G.; Santos, Jose O.; Wassermann, Julio C.

2005-01-01

In the last three decades, Sepetiba bay, located about 60 km south of the city of Rio de Janeiro, Brazil, has been subjected to increasing pollution impacts. The Sepetiba region has undergone fast industrial expansion leading to high levels of pollution by metals. For the last two decades, an industrial park composed of about 400 industrial plants, basically metallurgical, was established in the Sepetiba Bay basin, releasing its effluents either straight into the bay or through local rivers. Potential toxic elements such as As, Zn, Cr, Pb and Cd have been introduced into the bay through industrial and domestic wastes. In the present paper, instrumental neutron activation analysis (INAA) was applied to determine the elements As, Cr and Zn in sediments from Sepetiba bay, sampled in August 2003, in order to compare to previous results obtained in 1998, for these elements, by Pellegatti et al. (2001). By using a geostatistical model it was possible to evaluate the spatial mobility of As, Cr and Zn in the last six years. The results obtained showed that none of the studied elements showed a significant spatial mobility. This behavior is probably related to geochemical barriers present in Sepetiba bay. (author)

Like so many of South Africa's linefish species, the galjoen ...

African Journals Online (AJOL)

spamer

that the numbers of galjoen are decreasing is difficult to find, …” ... Marine & Coastal Management, Private Bag X2, Rogge Bay 8012, South Africa, and Zoology Department, University of Cape Town, ... then used as a basis to plan a monitoring programme. MATERIAL ..... mean, and µ# are the factors for which the subscripts.

Shark Spotters: Successfully reducing spatial overlap between white sharks (Carcharodon carcharias) and recreational water users in False Bay, South Africa.

Science.gov (United States)

Engelbrecht, Tamlyn; Kock, Alison; Waries, Sarah; O'Riain, M Justin

2017-01-01

White sharks (Carcharodon carcharias) are apex predators that play an important role in the structure and stability of marine ecosystems. Despite their ecological importance and protected status, white sharks are still subject to lethal control to reduce the risk of shark bites for recreational water users. The Shark Spotters program, pioneered in Cape Town, South Africa, provides a non-lethal alternative for reducing the risk of human-shark conflict. In this study we assessed the efficacy of the Shark Spotters program in reducing overlap between water users and white sharks at two popular beaches in False Bay, South Africa. We investigated seasonal and diel patterns in water use and shark presence at each beach, and thereafter quantified the impact of different shark warnings from shark spotters on water user abundance. We also assessed the impact of a fatal shark incident on patterns of water use. Our results revealed striking diel and seasonal overlap between white sharks and water users at both beaches. Despite this, there was a low rate of shark-human incidents (0.5/annum) which we attribute partly to the success of the Shark Spotters program. Shark spotters use visual (coloured flags) and auditory (siren) cues to inform water users of risk associated with white shark presence in the surf zone. Our results showed that the highest risk category (denoted by a white flag and accompanying siren) caused a significant reduction in water user abundance; however the secondary risk category (denoted by a red flag with no siren) had no significant effect on water users. A fatal shark incident was shown to negatively impact the number of water users present for at least three months following the incident. Our results indicate that the Shark Spotters program effectively reduces spatial overlap between white sharks and water users when the risk of conflict is highest.

Application of year-round atmospheric transmission data, collected with the MSRT multiband transmissometer during the FATMOSE trial in the False Bay area

NARCIS (Netherlands)

Jong, A.N. de; Eijk, A.M.J. van; Cohen, L.H.; Fritz, P.J.; Gunter, W.H.; Vrahimisb, G.; Faith, J.

2011-01-01

The FATMOSE trial (False Bay Atmospheric Experiment) is a continuation of the cooperative work between TNO and IMT on atmospheric propagation and point target detection and identification in a maritime environment (South Africa). The atmospheric transmission, being of major importance for target

Speciation of Metals and Assessment of Contamination in Surface Sediments from Daya Bay, South China Sea

Directory of Open Access Journals (Sweden)

Jie Yang

2014-12-01

Full Text Available The contents, speciation, source factors and potential ecological risks of the selected metals (Cr, Ni, Cu, Pb, Zn, Cd and As were analyzed in surface sediments from Daya Bay (DYB. The results show that, with the exception of Pb, metal concentrations have decreased at all sites over the past decade. The distribution features of these concentrations represent a ring shape that descends from shore to bay by varying degrees. Speciation analysis showed that Cr, Ni, Cu, Zn and As exist mainly in the residual fraction and, thus, are of low bioavailability, while Cd and Pb were found to be abundant in the non-residual fraction and, thus, have high potential mobility. The ratio of heavy metals in non-residual form in descending order is Pb (78.83%, Cd (78.65%, Cu (48.54%, Zn (48.10%, Ni (38.31%, Cr (28.43% and As (27.76%. The ratio of Pb content is the highest, meaning the highest mobility of Pb. The metals’ potential ecological risks to the environment were also assessed using the methods of the mean effect range-median quotient and the criteria of risk assessment code. The results showed that Cd presents the highest risk, and Pb and Cu are generally considered to be medium risks in the sub-basins of Daya Bay. The principal component analysis (PCA revealed that natural coastal weathering and erosion of rock caused the highest input, followed by mariculture and industrial wastewater and, finally, domestic sewage discharge.

Discharge, water-quality characteristics, and nutrient loads from McKay Bay, Delaney Creek, and East Bay, Tampa, Florida, 1991-1993

Science.gov (United States)

Stoker, Y.E.; Levesque, V.A.; Fritz, E.M.

1996-01-01

Nutrient enrichment in Tampa Bay has caused a decline in water quality in the estuary. Efforts to reduce the nutrient loading to Tampa Bay have resulted in improvement in water quality from 1981 to 1991. However, Tampa Bay still is onsidered enriched with nutrients. Water quality in East Bay (located at the northeastern part of Hillsborough Bay, which is an embayment in Tampa Bay) is not improving at the same rate as the rest of the bay. East Bay is the center of shipping activity in Tampa Bay and the seventh largest port in the United States. One of the primary cargoes is phosphate ore and related products such as fertilizer. The potential for nutrient loading to East Bay from shipping activities is high and has not previously been measured. Nitrogen and phosphorus loads from East Bay to Hillsborough Bay were measured during selected time periods during June 1992 through May 1993; these data were used to estimate seasonal and annual loads. These loads were evaluated to determine whether the loss of fertilizer products from shipping activities resulted in increased nutrient loading to Hillsborough Bay. Discharge was measured, and water-quality samples were collected at the head of East Bay (exiting McKay Bay), and at the mouth of East Bay. Discharge and nitrogen and phosphorus concentrations for the period June 1992 through May 1993 were used to compute loads. Discharges from McKay Bay, Delaney Creek, and East Bay are highly variable because of the effect of tide. Flow patterns during discharge measurements generally were unidirectional in McKay Bay and Delaney Creek, but more complex, bidirectional patterns were observed at the mouth of East Bay. Tidally affected discharge data were digitally filtered with the Godin filter to remove the effects of tide so that residual, or net, discharge could be determined. Daily mean discharge from McKay Bay ranged from -1,900 to 2,420 cubic feet per second; from Delaney Creek, -3.8 to 162 cubic feet per second; and from East

46 CFR 7.20 - Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and...

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island Sound and easterly entrance to Long Island Sound, NY. 7.20 Section 7.20... Atlantic Coast § 7.20 Nantucket Sound, Vineyard Sound, Buzzards Bay, Narragansett Bay, MA, Block Island...

33 CFR 165.1182 - Safety/Security Zone: San Francisco Bay, San Pablo Bay, Carquinez Strait, and Suisun Bay, CA.

Science.gov (United States)

2010-07-01

... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety/Security Zone: San... Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY... Areas Eleventh Coast Guard District § 165.1182 Safety/Security Zone: San Francisco Bay, San Pablo Bay...

H10493: NOS Hydrographic Survey , Biscayne Bay, Florida, 1993-09-20

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...

Apparent characteristics and taxonomic study of macroalgae in Pattani Bay

Directory of Open Access Journals (Sweden)

Naruemol Pianthumdee

2007-07-01

Full Text Available 2A survey on macroalgae in Pattani Bay was carried out to build up a database resource for the management of algae in the area. From February 2004 to March 2005, samples of macroalgae from 10 sites were randomly collected monthly. Macroalgae were found at 4 sites in the north of the bay, namely Laem Tachi, Lighthouse, Ban Bu Di and Ban Ta Lo Samilae; 3 sites in the east, namely Ban Da To, the Yaring River Mouth and Ban Bang Pu and only one site in the south at Ban Tanyong Lu Lo. Twelve species of 3 divisions of macroalgae were detected. They were Division Cyanophyta, Lyngbya majuscula (Dillwyn Harvey ex Gomont; Division Chlorophyta; Ulva intestinalis Linnaeus, U. pertusa Kjellman and U. reticulata Forsskal, Rhizoclonium riparium (Roth Harvey, R. tortuosum Kutzing, Chaetomorpha crassa (C. Agardh Kutzing and Cladophora sp.; and Division Rhodophyta, namely Gracilaria tenuistipitata Chang et Xia, G. fisheri (Xia et Abbott Abbott, Zhang et Xia, Hypnea spinella (C. Agardh Kutzing and Acanthophora spicifera (Vahl B∅rgesen. Among them, four species were new recordings at Pattani Bay: Lyngbya majuscula, Rhizoclonium riparium, R. tortuosum and Acanthophora spicifera. Most of these seaweeds were found at the east sites in the dry season from February to September 2004 and from January to March 2005. Only a few species could be found in the wet season from November to December 2004.

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

Science.gov (United States)

2013-10-15

... Safety Zone, Oyster Festival 30th Anniversary Fireworks Display, Oyster Bay; Oyster Bay, NY AGENCY: Coast... zone on the navigable waters of Oyster Bay near Oyster Bay, NY for the Oyster Festival 30th Anniversary... Oyster Festival 30th Anniversary Fireworks Display is scheduled for October 19, 2013 and is one of...

Detection of DDT and its metabolites in two estuaries of South China using a SPME-based device: First report of p,p'-DDMU in water column

International Nuclear Information System (INIS)

Xing Yuanna; Guo Ying; Xie Mei; Shen Rulang; Zeng, Eddy Y.

2009-01-01

A solid-phase microextration-based sampling method was employed to determine the concentrations of 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane (DDT) and its metabolites, 1,1-dichloro-2,2-bis(p-chlorophenyl)ethane (DDD), 1,1-dichloro-2,2-bis(p-chlorophenyl)ethene (DDE) and 1-chloro-2,2-bis(p-chlorophenyl)ethene (DDMU), in two estuarine bays, Daya Bay and Hailing Bay, of South China. Six DDT components including p,p'-DDT, o,p'-DDD, p,p'-DDD, o,p'-DDE, p,p'-DDE, and p,p'-DDMU were detected in Hailing Bay, while only p,p'-DDD was found in Daya Bay. p,p'-DDD was the most abundant DDT component in both bays, sharply different from the previous finding in the water column of the Palos Verdes Shelf, California, USA that p,p'-DDE was prevalent. In addition, the occurrence of p,p'-DDMU (with a range of 0.047-0.21 ng/L in Hailing Bay) has not been reported around the globe, and its presence in our study region appeared to stem from dehydrochlorination of p,p'-DDD, favored under aerobic conditions, but further investigations are clearly needed to confirm the mechanism for generation of DDMU in estuarine environments. - DDT and its metabolites, particularly p,p'-DDMU, are detected in the water column of two estuarine bays in South China using a SPME-based sampler

Still Bay Point-Production Strategies at Hollow Rock Shelter and Umhlatuzana Rock Shelter and Knowledge-Transfer Systems in Southern Africa at about 80-70 Thousand Years Ago

Science.gov (United States)

Lombard, Marlize

2016-01-01

It has been suggested that technological variations associated with Still Bay assemblages of southern Africa have not been addressed adequately. Here we present a study developed to explore regional and temporal variations in Still Bay point-production strategies. We applied our approach in a regional context to compare the Still Bay point assemblages from Hollow Rock Shelter (Western Cape) and Umhlatuzana Rock Shelter (KwaZulu-Natal). Our interpretation of the point-production strategies implies inter-regional point-production conventions, but also highlights variability and intra-regional knapping strategies used for the production of Still Bay points. These strategies probably reflect flexibility in the organisation of knowledge-transfer systems at work during the later stages of the Middle Stone Age between about 80 ka and 70 ka in South Africa. PMID:27942012

Steroid markers to assess sewage and other sources of organic contaminants in surface sediments of Cienfuegos Bay, Cuba.

Science.gov (United States)

Tolosa, I; Mesa, M; Alonso-Hernandez, C M

2014-09-15

Analyses of faecal steroids in coastal sediments from Cienfuegos Bay Cuba indicate chronic sewage contamination at the main outfalls from the city, where concentrations of coprostanol up to 5400ngg(-)(1) (dry wt) were measured. In contrast, steroid concentrations and compositions from sites from the south part of the Bay are characteristic of uncontaminated sewage environments. The levels of coprostanol in the Cienfuegos sediments compares to the lower to mid-range of concentrations reported for coastal sediments on a world-wide basis, with sedimentary levels markedly below those previously reported for heavily impacted sites. This study delivers baseline data for further investigation of the effectiveness of the proposed sewerage plan promoted by the GEF project in Cienfuegos. Investigations on the correlations between faecal steroids and other organic contaminants confirmed that the major source of petroleum hydrocarbons within the bay was associated with the sewage effluents from the Cienfuegos city. Copyright © 2014 Elsevier Ltd. All rights reserved.

Shifting shoals and shattered rocks : How man has transformed the floor of west-central San Francisco Bay

Science.gov (United States)

Chin, John L.; Wong, Florence L.; Carlson, Paul R.

2004-01-01

subembayments--north bay (San Pablo and Suisun Bays), central bay, and south bay--each characterized by a central area of open water surrounded by intertidal mudflats and marshes. Central bay includes Alcatraz and Angel Islands and also a number of submerged bedrock knobs that protrude through the sediment of the bay floor and rise to within about 40 feet (12 m) of the water surface. The most prominent of these are Harding, Shag, Arch, and Blossom Rocks. These rocks have been lowered by blasting several times in the past, but they remain a potential hazard to shipping because newer cargo vessels are designed with increasingly deeper drafts. Central bay's location adjacent to two major population and commerce centers, San Francisco and Oakland, subjects it to greater human influences than less developed parts of the estuary. The western part of central San Francisco Bay is adjacent to the Golden Gate, the estuary's outlet to the Pacific Ocean. The changing submarine topography of the west-central bay, as well as its geology, form the main focus of this book.

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...

Antibiotics in the coastal environment of the Hailing Bay region, South China Sea: Spatial distribution, source analysis and ecological risks

International Nuclear Information System (INIS)

Chen, Hui; Liu, Shan; Xu, Xiang-Rong; Zhou, Guang-Jie; Liu, Shuang-Shuang; Yue, Wei-Zhong; Sun, Kai-Feng; Ying, Guang-Guo

2015-01-01

Highlights: • Thirty-eight antibiotics were systematically investigated in marine environment. • The distribution of antibiotics was significantly correlated with COD and NO 3 –N. • Untreated domestic sewage was the primary source of antibiotics. • Fluoroquinolones showed a strong sorption capacity onto sediments. • Oxytetracycline, norfloxacin and erythromycin–H 2 O indicated high risks. - Abstract: In this study, the occurrence and spatial distribution of 38 antibiotics in surface water and sediment samples of the Hailing Bay region, South China Sea, were investigated. Twenty-one, 16 and 15 of 38 antibiotics were detected with the concentrations ranging from <0.08 (clarithromycin) to 15,163 ng/L (oxytetracycline), 2.12 (methacycline) to 1318 ng/L (erythromycin–H 2 O), <1.95 (ciprofloxacin) to 184 ng/g (chlortetracycline) in the seawater, discharged effluent and sediment samples, respectively. The concentrations of antibiotics in the water phase were correlated positively with chemical oxygen demand and nitrate. The source analysis indicated that untreated domestic sewage was the primary source of antibiotics in the study region. Fluoroquinolones showed strong sorption capacity onto sediments due to their high pseudo-partitioning coefficients. Risk assessment indicated that oxytetracycline, norfloxacin and erythromycin–H 2 O posed high risks to aquatic organisms

Site formation processes at Pinnacle Point Cave 13B (Mossel Bay, Western Cape Province, South Africa): resolving stratigraphic and depositional complexities with micromorphology.

Science.gov (United States)

Karkanas, Panagiotis; Goldberg, Paul

2010-01-01

Site PP13B is a cave located on the steep cliffs of Pinnacle Point near Mossel Bay in Western Cape Province, South Africa. The depositional sequence of the cave, predating Marine Isotopic Stage 11 (MIS 11) and continuing to present, is in the form of isolated sediment exposures with different depositional facies and vertical and lateral variations. Micromorphological analysis demonstrated that a suite of natural sedimentation processes operated during the development of the sequence ranging from water action to aeolian activity, and from speleothem formations to plant colonization and root encrustation. At the same time, anthropogenic sediments that are mainly in the form of burnt remains from combustion features (e.g., wood ash, charcoal, and burnt bone) were accumulating. Several erosional episodes have resulted in a complicated stratigraphy, as discerned from different depositional and post-depositional features. The cave is associated with a fluctuating coastal environment, frequent changes in sea level and climate controlled patterns of sedimentation, and the presence or absence of humans. Copyright © 2010 Elsevier Ltd. All rights reserved.

Archive of bathymetry data collected in South Florida from 1995 to 2015

Science.gov (United States)

Hansen, Mark Erik; DeWitt, Nancy T.; Reynolds, Billy J.

2017-08-10

DescriptionLand development and alterations of the ecosystem in south Florida over the past 100 years have decreased freshwater and increased nutrient flows into many of Florida's estuaries, bays, and coastal regions. As a result, there has been a decrease in the water quality in many of these critical habitats, often prompting seagrass die-offs and reduced fish and aquatic life populations. Restoration of water quality in many of these habitats will depend partly upon using numerical-circulation and sediment-transport models to establish water-quality targets and to assess progress toward reaching restoration targets. Application of these models is often complicated because of complex sea floor topography and tidal flow regimes. Consequently, accurate and modern sea-floor or bathymetry maps are critical for numerical modeling research. Modern bathymetry data sets will also permit a comparison to historical data in order to help assess sea-floor changes within these critical habitats. New and detailed data sets also support marine biology studies to help understand migratory and feeding habitats of marine life.This data series is a compilation of 13 mapping projects conducted in south Florida between 1995 and 2015 and archives more than 45 million bathymetric soundings. Data were collected primarily with a single beam sound navigation and ranging (sonar) system called SANDS developed by the U.S. Geological Survey (USGS) in 1993. Bathymetry data for the Estero Bay project were supplemented with the National Aeronautics and Space Administration's (NASA) Experimental Advanced Airborne Research Lidar (EAARL) system. Data from eight rivers in southwest Florida were collected with an interferometric swath bathymetry system. The projects represented in this data series were funded by the USGS Coastal and Marine Geology Program (CMGP), the USGS South Florida Ecosystem Restoration Project- formally named Placed Based Studies, and other non-Federal agencies. The purpose of

Classification using Hierarchical Naive Bayes models

DEFF Research Database (Denmark)

Langseth, Helge; Dyhre Nielsen, Thomas

2006-01-01

Classification problems have a long history in the machine learning literature. One of the simplest, and yet most consistently well-performing set of classifiers is the Naïve Bayes models. However, an inherent problem with these classifiers is the assumption that all attributes used to describe......, termed Hierarchical Naïve Bayes models. Hierarchical Naïve Bayes models extend the modeling flexibility of Naïve Bayes models by introducing latent variables to relax some of the independence statements in these models. We propose a simple algorithm for learning Hierarchical Naïve Bayes models...

75 FR 11837 - Chesapeake Bay Watershed Initiative

Science.gov (United States)

2010-03-12

... DEPARTMENT OF AGRICULTURE Commodity Credit Corporation Chesapeake Bay Watershed Initiative AGENCY...: Notice of availability of program funds for the Chesapeake Bay Watershed Initiative. SUMMARY: The... through the Chesapeake Bay Watershed Initiative for agricultural producers in the Chesapeake Bay watershed...

Urban Greening Bay Area

Science.gov (United States)

Information about the San Francisco Bay Water Quality Project (SFBWQP) Urban Greening Bay Area, a large-scale effort to re-envision urban landscapes to include green infrastructure (GI) making communities more livable and reducing stormwater runoff.

Determination of heavy metals and other elements in sediments from Sepetiba Bay (RJ, Brazil) by neutron activation analysis

International Nuclear Information System (INIS)

Pellegatti, Fabio

2000-01-01

Sepetiba Bay, located about 60 km south of the city of Rio de Janeiro, Brazil, is one of the most important fishery areas in the State of Rio de Janeiro. A large harbor brought up a lot of industrial investment in that area. Since the 1970's, the Sepetiba region has undergone fast industrial expansion, leading to high levels of pollution by metals. For the last two decades, an industrial park composed of about 400 industrial plants, basically metallurgical, was established in the Sepetiba Bay basin, releasing its industrial waste either straight into the bay or through local rivers. Metal contamination in the bay for some metals, such as Zn, has already exceeded acceptable levels. Many authors have studied the distribution and behavior of heavy metals and another elements in the bay, but only few elements have been focused (Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn). This is probably due to the fact that the analytical technique most employed has been atomic absorption spectrometry, which is not a multi-elemental technique. In this work, Instrumental Neutron Activation Analysis (INAA) was applied to the determination of the elements As, Ba, Br, Ce, Co, Cr, Cs, Eu, Fe, Hf, La, Lu, Nd, Rb, Sc, Sm, Ta, Tb, Th, U, Yb and Zn in 28 bottom sediment samples and four sediment cores from Sepetiba Bay. The elements Co, Cr, Cs, Fe, Sc, Ta and Zn presented similar behavior in the bottom sediments, showing higher concentration along the Northern coast of the bay, where most of the fluvial water flows out to the bay. The contamination of Sepetiba Bay was also assessed by the analysis of four sediment cores. Two of them were sampled in the Eastern part of the bay, where the industrial park is located, whereas the other two were sampled in the Western part of the bay, a more preserved region. For each region, two cores were sampled within the mangrove trees and the others at the edge of the tidal flat. The results showed that, the sediments displayed higher metal concentration within the

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

Concentration of PSP (Paralytic Shellfish Poisoning) Toxin On Shellfish From Inner Ambon Bay and Kao Bay North Halmahera

Science.gov (United States)

Pello, F. S.; Haumahu, S.; Huliselan, N. V.; Tuapattinaja, M. A.

2017-10-01

The Inner Ambon Bay and Kao Bay have potential on fisheries resources which one of them is molluscs. Molluscs especially for class bivalve have economical values and are consumed by coastal community. The research had been done to analyze saxitoxin (STX) concentration on bivalves from Kao Bay and Inner Ambon Bay. The Saxitoxin Elisa Test Kit Protocol was used to determine saxitoxin concentration. The measurement showed that the highest concentration of saxitoxin (392.42 µg STXeq/100g shellfish meat) was Gafrarium tumidum from Ambon Bay, whereas concentration of saxitoxin (321.83 µg STXeq/100g shellfish meat) was Mactra mera from Kao Bay

Petroleum pollution in surface sediments of Daya Bay, South China, revealed by chemical fingerprinting of aliphatic and alicyclic hydrocarbons

Science.gov (United States)

Gao, Xuelu; Chen, Shaoyong

2008-10-01

Nine surface sediments collected from Daya Bay have been Soxhlet-extracted with 2:1 (v/v) dichloromethane-methanol. The non-aromatic hydrocarbon (NAH) fraction of solvent extractable organic matter (EOM) and some bulk geochemical parameters have been analyzed to determine petroleum pollution of the bay. The NAH content varies from 32 to 276 μg g -1 (average 104 μg g -1) dry sediment and accounts for 5.8-64.1% (average 41.6%) of the EOM. n-Alkanes with carbon number ranging from 15 to 35 are identified to be derived from both biogenic and petrogenic sources in varying proportions. The contribution of marine authigenic input to the sedimentary n-alkanes is lower than the allochthonous input based on the average n-C 31/ n-C 19 alkane ratio. 25.6-46.5% of the n-alkanes, with a mean of 35.6%, are contributed by vascular plant wax. Results of unresolved complex mixture, isoprenoid hydrocarbons, hopanes and steranes also suggest possible petroleum contamination. There is strong evidence of a common petroleum contamination source in the bay.

A comparison of the radioactivity levels in the coastal waters between the great wall and Zhongshan stations in Antarctica and the Pohai, Huanghai, east China and south China seas of China

International Nuclear Information System (INIS)

Chen Jinxing

1992-01-01

A comparison of radioactivity levels in the coastal sediments and plants between the Great Wall and Zhongshan Stations in Antarctica and the four seas (i.e. the Pohai Sea, Huanghai Sea, East China Sea and South China Sea) in China shows that in general the radioactivity levels in the coastal sediments and plants in Antarctica are lower than those in the four seas in China. The contents of the total β in the sediments decrease from higher to lower in amount in the order of East China Sea, South China Sea, Pohai Sea, Huanghai Sea and the Great Wall Bay in Antarctica successively, but the contents of 238 U, 232 Th, 226 Ra, 40 K and the total β in marine plants decrease from higher to lower in amount in the order of Daya Bay in the South China Sea, Hanzhou Bay in the East China Sea and the Great Wall Bay in Antarctica successively. The results show that the contamination levels of radioactivity, especially the artificial radioactive contamination in the Antarctic coastal area are far lower than those in China Coastal area, with the remarkable exception of 137 Cs

Description of gravity cores from San Pablo Bay and Carquinez Strait, San Francisco Bay, California

Science.gov (United States)

Woodrow, Donald L.; John L. Chin,; Wong, Florence L.; Fregoso, Theresa A.; Jaffe, Bruce E.

2017-06-27

Seventy-two gravity cores were collected by the U.S. Geological Survey in 1990, 1991, and 2000 from San Pablo Bay and Carquinez Strait, California. The gravity cores collected within San Pablo Bay contain bioturbated laminated silts and sandy clays, whole and broken bivalve shells (mostly mussels), fossil tube structures, and fine-grained plant or wood fragments. Gravity cores from the channel wall of Carquinez Strait east of San Pablo Bay consist of sand and clay layers, whole and broken bivalve shells (less than in San Pablo Bay), trace fossil tubes, and minute fragments of plant material.

Population genetic analyses are consistent with the introduction of Ceramium secundatum (Ceramiaceae, Rhodophyta) to Narragansett Bay, Rhode Island, USA.

Science.gov (United States)

Bruce, Meghann R; Saunders, Gary W

2015-11-01

During ongoing DNA barcode (COI-5P) surveys of the macroalgal flora along the northwest Atlantic coast, we discovered a population of Ceramium secundatum in Narragansett Bay, Rhode Island, USA. This species is regarded as common and widespread in the northeast Atlantic, ranging from Norway to Morocco, but until now has not been reported from the western Atlantic. Several lines of evidence suggest that C. secundatum may be introduced to Narragansett Bay: (1) despite extensive collecting, specimens have only been obtained from a limited geographic range in the northwest Atlantic; (2) three other nonindigenous seaweed species are reportedly introduced in this region, which is thought to be a consequence of shipping; and (3) this species is introduced to South Africa and New Zealand. To investigate this suspected introduction, we applied population genetic analyses (using the cox2-3 spacer) to compare the Narragansett Bay C. secundatum population to native populations in the Republic of Ireland and the United Kingdom. Collectively, analyses of biogeographical and molecular data indicate that C. secundatum is likely introduced to Narragansett Bay. The implications of this discovery are discussed.

Luminescence chronology of loess-paleosol sequences from Canterbury, South Island, New Zealand

International Nuclear Information System (INIS)

Berger, G.W.; Pillans, B.J.; Tonkin, P.J.

2001-01-01

The extensive Quaternary loess-paleosol deposits of South Island, New Zealand, represent one of the major proxy records of paleoclimatic changes in the Southern Hemisphere. We attempted to produce the first numeric chronology of these subaerial sequences in the Canterbury region by using thermoluminescence and infrared-stimulated luminescence dating methods. We examined five exposures: a 6 m thick section at Cust, north of Christchurch; two thicker (c. 14 m) sequences on Banks Peninsula (Barrys Bay and Onawe sites); farther south, a c. 12 m sequence in Timaru; and a c. 7 m sequence on the coast at the Normanby site near Timaru. Our results are largely based on single experiments per sample, and therefore provide imprecise ages for several of the older samples. The most satisfactory results are those from the youngest site (Cust), for which three samples were dated. Here, phases of maximum loess deposition are dated at 73 +/- 13 ka (basal loess-paleosol unit L3), 41 +/- 5 ka (basal L2), and 27 +/- 3 ka (basal L1). At Barrys Bay an age of 70 +/- 15 ka was obtained in the basal L1, and at Timaru two separate samples in the base of L1 also yielded ages of c. 70 ka, thus correlating the entire Cust loess sequence with the L1 loess unit at these two other study sites. Only at Barrys Bay were ages (c. 130-250 ka) in stratigraphic order obtained for older samples (units L2 and deeper). At the other sites, some samples in the sub-L1 units gave age reversals, and some (including the oldest sample at Barrys Bay) yielded poor precision (e.g., 20%). Units L2 at Timaru and Barrys Bay may correlate to all or part of MIS 6; however, the poor precision and some age reversals in other units at these sites and at Normanby and Onawe preclude any unambiguous correlations between sites or to the MIS time-scale. Nevertheless, in the absence of any prior numeric ages, these first results serve as a basis for more precise future dating of these units. Although these reconnaissance dating

75 FR 15343 - Regulated Navigation Area: Narragansett Bay, RI and Mount Hope Bay, RI and MA, Including the...

Science.gov (United States)

2010-03-29

...: Narragansett Bay, RI and Mount Hope Bay, RI and MA, Including the Providence River and Taunton River AGENCY... River and Mount Hope Bay in the vicinity of the two Brightman Street bridges have not been adopted and... Island and Mt. Hope Bay, MA.'' The notice was prompted primarily by two events: (1) The U.S. Army Corps...

Support for EU fundraising in the field of Environment & Energy - BayFOR

Science.gov (United States)

Ammerl, Thomas; Baumann, Cornelia; Reiter, Andrea; Blume, Andreas; Just, Jana; Franke, Jan

2013-04-01

The Bavarian Research Alliance (BayFOR, http://www.bayfor.org) is a private company for the support of Bavaria (Free State in the South East of Germany) as a centre for science and innovation within the European Research Area. It was set up on the initiative of the Bavarian universities to strengthen their networking at regional, national and international level while helping them to prepare to meet the requirements for European research funding. The focus is directed at the current EU Framework Programme (FP7) and the forthcoming Framework Programme for Research and Innovation "Horizon 2020", but also comprises the wide range of European programmes (e.g. FP7, LIFE+, Interreg, COST, EUREKA, ERA-Nets, IEE (CIP), LLP, Calls for tender). BayFOR is also a partner institution in the Bavarian "Haus der Forschung" (www.hausderforschung.bayern.de/en). BayFORs overall aim is to strengthen and permanently anchor the science and innovation location of Bavaria in the European Research Area through: a) Initiation of national and in particular European innovation and science partnerships from academia and business b) Improvement of innovation potential of Bavarian universities and SME c) Support in acquisition, management and dissemination of results of European and international projects in the field of research and technological development The service portfolio of the EU Funding Advisory Service reaches from the first project idea to project implementation. The minimum condition for BayFOR support is at least one partner from Bavaria (Germany) must be part of the applying consortium: a) Recommendation of funding programmes/instruments (incl. integration of relevant EU policies & directives) b) Partner search c) Project development and proposal elaboration (Online platform, Creation of consortium, Attendance at meetings, Preparation of documents, Proposal structure elaboration, Provision of templates, Editorial support: Gantt, PERT, Impact, EU added value) d) Support in the

Net phytoplankton of the Admiralty Bay (King George Island, South Shetland Islands) in 1983

OpenAIRE

Ligowski, Ryszard

1986-01-01

Paper received 13 July 1985. Phytoplankton sampling from 13 stations situated in Admiralty Bay was carried out in March. April, May, October and November 1983. Wet settling volume of seston, its dry weight, number of cells under 1 m², and qualitative composition of phytoplankton were determined. It was found that amount of phytoplankton was decreasing in April and increasing again in November after the winter season. The share of benthic and periphyton species in the qualita...

Shark and skate egg-cases cast up on two South African beaches ...

African Journals Online (AJOL)

Collections of chondrichthyan egg-cases cast ashore at two sites along the South African coastline were identified and examined for cause of mortality. A total of 574 egg-cases collected from False Bay could be attributed to five species of scyliorhinid shark. two skates and the elephantfish or chimaera, while the 538 ...

Historical sediment budget and present-day catchment-shoreline coupling at Twofold Bay, southeastern Australia

Science.gov (United States)

Tamura, T.; Oliver, T.; Hudson, J.; Woodroffe, C. D.

2017-12-01

Considering projected impacts of sea-level rise in the 21st century on sandy shorelines, an understanding of long-term sediment budget for individual beaches or coastal compartments supports assessments of shoreline stability. We examined a low-lying coastal beach-ridge barrier in Twofold Bay using optically stimulated luminescence (OSL) dating , airborne LiDAR, sedimentological analysis and seismic data to assess changes in rates of sediment supply to this shoreline through time. Calculations of barrier volume, Twofold Bay bay-floor sediment volume and estimates of sediment delivery from a proximal river system provide a broad-scale assessment of past-sediment budget. Between ca. 7500 years ago and 1500 years ago, sources of sediment for shoreline progradation at Boydtown were bay-floor sediments either inherited or moved into the embayment during late-stage transgression. Progradation rate between ca. 7500-1500 years ago was 0.16 m/yr with subaerial barrier volume accumulating at 0.46 m3/m/yr. Between ca. 1500 years and present day, the Towamba River to the south has delivered additional sediment to the Boydtown shoreline more than doubling shoreline progradation rate to 0.65 m/yr and subaerial barrier accumulation has risen to 1.83 m3/m/yr. The delivery of fluvial sediment from the Towamba River was restricted to the past ca. 1500 years as prior to this, estuary infilling prevented floods delivering sediments to the bay. This recent historical coupling of river sand supply and shoreline progradation rate implies that anthropogenic modifications to the Towamba River catchment such as river damming, or climatic changes reducing rainfall or runoff, would negatively impact the Boydtown Beach shoreline. Conversely increased rainfall or deforestation may increase sediment discharge due to upstream erosion. The Boydtown shoreline within Twofold Bay may be able to maintain its current position in the coming century if fluvial sediment delivery continues. The fact that

Bay breeze climatology at two sites along the Chesapeake bay from 1986-2010: Implications for surface ozone.

Science.gov (United States)

Stauffer, Ryan M; Thompson, Anne M

Hourly surface meteorological measurements were coupled with surface ozone (O 3 ) mixing ratio measurements at Hampton, Virginia and Baltimore, Maryland, two sites along the Chesapeake Bay in the Mid-Atlantic United States, to examine the behavior of surface O 3 during bay breeze events and quantify the impact of the bay breeze on local O 3 pollution. Analyses were performed for the months of May through September for the years 1986 to 2010. The years were split into three groups to account for increasingly stringent environmental regulations that reduced regional emissions of nitrogen oxides (NO x ): 1986-1994, 1995-2002, and 2003-2010. Each day in the 25-year record was marked either as a bay breeze day, a non-bay breeze day, or a rainy/cloudy day based on the meteorological data. Mean eight hour (8-h) averaged surface O 3 values during bay breeze events were 3 to 5 parts per billion by volume (ppbv) higher at Hampton and Baltimore than on non-bay breeze days in all year periods. Anomalies from mean surface O 3 were highest in the afternoon at both sites during bay breeze days in the 2003-2010 study period. In conjunction with an overall lowering of baseline O 3 after the 1995-2002 period, the percentage of total exceedances of the Environmental Protection Agency (EPA) 75 ppbv 8-h O 3 standard that occurred on bay breeze days increased at Hampton for 2003-2010, while remaining steady at Baltimore. These results suggest that bay breeze circulations are becoming more important to causing exceedance events at particular sites in the region, and support the hypothesis of Martins et al. (2012) that highly localized meteorology increasingly drives air quality events at Hampton.

Levels and bioaccumulation of organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs) in fishes from the Pearl River estuary and Daya Bay, South China

International Nuclear Information System (INIS)

Guo Lingli; Qiu Yaowen; Zhang Gan; Zheng, Gene J.; Lam, Paul K.S.; Li Xiangdong

2008-01-01

Fifty fish samples were collected from the Pearl River estuary (PRE) and Daya Bay, South China and were analyzed for DDTs, HCHs, chlordanes and polybrominated biphenyl ethers (PBDEs). Except the high concentrations of DDT observed in fishes, the concentrations of HCHs, chlordanes and PBDEs were low when compared to other regions. BDE-47 was the predominant PBDE congener and the BDE-209 concentrations were relatively low, despite its high concentration in surface sediments. The absence of significant increase of DDT, HCH, chlordane and PBDE concentrations towards higher δ 15 N values, as well as the lack of a significant correlation (p 15 N, may indicate a weak biomagnification of these chemicals in the food webs. Good agreement was observed between their concentrations and lipid contents of the organisms. Bioconcentration was suggested to be responsible for the accumulation of OCPs and PBDEs in the lower trophic organisms in the studied subtropical waters. - Bioconcentration was suggested to be responsible for the accumulation of OCPs and PBDEs in the lower trophic organisms of subtropical waters

Monitoring of bird abundance and distribution at McKinley Bay and Hutchison Bay, Northwest Territories, 1981 to 1993

Energy Technology Data Exchange (ETDEWEB)

Cornish, B J; Dickson, D L

1994-04-01

McKinley Bay has been identified as a preferred site for a harbor to support oil and gas production in the Beaufort Sea. As the bay is a molting area for several species of diving duck, a study was initiated to monitor the effect of harbor development on birds using the bay. Baseline information on the natural annual fluctuations in the number of birds were collected for nine years at McKinley Bay and eight years at neighboring Hutchinson Bay, an area chosen as the control. The final report of the predevelopment phase of the monitoring study is presented, including results of the 1993 surveys and a summary of results of all years of surveys. There were significantly more diving ducks in McKinley Bay in early August 1990 to 1993, on average, than from 1981 to 1985. No statistically significant change in total diving ducks was noted at Hutchinson Bay. Numbers of species of divers varied substantially between years at the two bays but not to the same degree. Significantly more Pacific loons, red-throated loons, and northern pintails were recorded in the 1990-1993 surveys at McKinley Bay than in earlier surveys. Potential explanations for the large between-year fluctuations in diving duck numbers are discussed. The variations may be due to bird responses to changes in the physical environment or related to the limitations of the aerial survey techniques used. Because of the large natural fluctuations in numbers of molting diving ducks using these bays in early August, it will be difficult to detect future impacts of industrial disturbance, even when sources of survey bias are minimized. It is concluded that aerial surveys of molting diving ducks in the two bays are unsuitable for monitoring the effects of industrial development. 41 refs., 7 figs., 23 tabs.

Benthic habitat classification in Lignumvitae Key Basin, Florida Bay, using the U.S. Geological Survey Along-Track Reef Imaging System (ATRIS)

Science.gov (United States)

Reich, C.D.; Zawada, D.G.; Thompson, P.R.; Reynolds, C.E.; Spear, A.H.; Umberger, D.K.; Poore, R.Z.

2011-01-01

The Comprehensive Everglades Restoration Plan (CERP) funded in partnership between the U.S. Army Corps of Engineers, South Florida Water Management District, and other Federal, local and Tribal members has in its mandate a guideline to protect and restore freshwater flows to coastal environments to pre-1940s conditions (CERP, 1999). Historic salinity data are sparse for Florida Bay, so it is difficult for water managers to decide what the correct quantity, quality, timing, and distribution of freshwater are to maintain a healthy and productive estuarine ecosystem. Proxy records of seasurface temperature (SST) and salinity have proven useful in south Florida. Trace-element chemistry on foraminifera and molluscan shells preserved in shallow-water sediments has provided some information on historical salinity and temperature variability in coastal settings, but little information is available for areas within the main part of Florida Bay (Brewster-Wingard and others, 1996). Geochemistry of coral skeletons can be used to develop subannually resolved proxy records for SST and salinity. Previous studies suggest corals, specifically Solenastrea bournoni, present in the lower section of Florida Bay near Lignumvitae Key, may be suitable for developing records of SST and salinity for the past century, but the distribution and species composition of the bay coral community have not been well documented (Hudson and others, 1989; Swart and others, 1999). Oddly, S. bournoni thrives in the study area because it can grow on a sandy substratum and can tolerate highly turbid water. Solenastrea bournoni coral heads in this area should be ideally located to provide a record (~100-150 years) of past temperature and salinity variations in Florida Bay. The goal of this study was to utilize the U.S. Geological Survey's (USGS) Along-Track Reef Imaging System (ATRIS) capability to further our understanding of the abundance, distribution, and size of corals in the Lignumvitae Key Basin. The

Concentrations and human health implications of heavy metals in wild aquatic organisms captured from the core area of Daya Bay's Fishery Resource Reserve, South China Sea.

Science.gov (United States)

Gu, Yang-Guang; Huang, Hong-Hui; Lin, Qin

2016-07-01

Heavy metal concentrations in edible organisms from the core area of Daya Bay's Fishery Resource Reserve, South China Sea, were determined. Samples of 14 crustacean, fish, and shellfish species were collected and analyzed. The As, Cd, Cr, Cu, Hg, Ni, Pb, and Zn concentrations were 0.18-1.16, 0.002-0.919, 0.40-2.85, 0.07-4.10, 0.004-0.055, 0.14-1.19, 0.014-0.070, and 4.57-15.94μg/g wet weight, respectively. The As concentrations were higher than the Chinese maximum permissible levels in all of the fish and shellfish species and two crustacean species, indicating that consumption of these wild species by humans may pose health risks. However, calculations of the health risks posed to humans indicated that no significant adverse health effects would be associated with consuming these species. Copyright © 2016 Elsevier B.V. All rights reserved.

Default Bayes factors for ANOVA designs

NARCIS (Netherlands)

Rouder, Jeffrey N.; Morey, Richard D.; Speckman, Paul L.; Province, Jordan M.

2012-01-01

Bayes factors have been advocated as superior to p-values for assessing statistical evidence in data. Despite the advantages of Bayes factors and the drawbacks of p-values, inference by p-values is still nearly ubiquitous. One impediment to the adoption of Bayes factors is a lack of practical

77 FR 21890 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

Science.gov (United States)

2012-04-12

... Street and Maple-Oregon Bridges so vehicular traffic congestion would not develop on downtown Sturgeon... the efficient movement of vehicular traffic in Sturgeon Bay. The Sturgeon Bay Ship Canal is... experiences a significant increase in vehicular and vessel traffic during the peak tourist and navigation...

Study on origin and sedimentary environment of marine sediments from Kii Channel, Hiroshima Bay and Tosa Bay

International Nuclear Information System (INIS)

Suzuki, Misaki

2008-01-01

The trace amounts of elements in the sediments of sea bottom in Kii Channel, Hiroshima Bay and Tosa Bay were determined quantitatively by the neutron activation analysis. The following facts were illustrated particularly from the quantitative analysis of scandium, rare earths, thorium and uranium: 1) It was known from Ce/La ratio that the geological feature in the west part of Japan is reflected in Kii Channel, Hiroshima Bay and Tosa Bay; 2) The rare-earth element pattern and La/Lu ratio suggest the fact that Kii Channel, Hiroshima Bay and Tosa Bay are essentially composed of the materials of which origin is land; 3) From the fact that Ce/La ratio in these sites are slightly under 1.0, these sites are considered to be affected mainly by the materials of which origin is land; 4) The sedimentary environment in the marine bottom of the Japanese coasts has been found to be mostly under a reductive state. (M.H.)

Airborne gamma-ray spectrometer and magnetometer survey Coos Bay, Oregon. Final report

International Nuclear Information System (INIS)

1981-05-01

During the months of August, September, and October of 1980, Aero Service Division Western Geophysical Company of America conducted an airborne high sensitivity gamma-ray spectrometer and magnetometer survey over ten (10) areas over northern California and southwestern Oregon. These include the 2 0 x 1 0 NTMS quadrangles of Roseburg, Medford, Weed, Alturas, Redding, Susanville, Ukiah, and Chico along with the 1 0 x 2 0 areas of the Coos Bay quadrangle and the Crescent City/Eureka areas combined. This report discusses the results obtained over the Coos Bay, Oregon, map area. Line spacing was generally six miles for east/west traverses and eighteen miles for north/south tie lines over the northern one-half of the area. Traverses and tie lines were flown at three miles and twelve miles respectively over the southern one-half of the area. A total of 16,880.5 line miles of geophysical data were acquired, compiled, and interpreted during the survey, of which 863.8 line miles are in this quadrangle

Dynamics of sediment carbon stocks across intertidal wetland habitats of Moreton Bay, Australia.

Science.gov (United States)

Hayes, Matthew A; Jesse, Amber; Hawke, Bruce; Baldock, Jeff; Tabet, Basam; Lockington, David; Lovelock, Catherine E

2017-10-01

Coastal wetlands are known for high carbon storage within their sediments, but our understanding of the variation in carbon storage among intertidal habitats, particularly over geomorphological settings and along elevation gradients, is limited. Here, we collected 352 cores from 18 sites across Moreton Bay, Australia. We assessed variation in sediment organic carbon (OC) stocks among different geomorphological settings (wetlands within riverine settings along with those with reduced riverine influence located on tide-dominated sand islands), across elevation gradients, with distance from shore and among habitat and vegetation types. We used mid-infrared (MIR) spectroscopy combined with analytical data and partial least squares regression to quantify the carbon content of ~2500 sediment samples and provide fine-scale spatial coverage of sediment OC stocks to 150 cm depth. We found sites in river deltas had larger OC stocks (175-504 Mg/ha) than those in nonriverine settings (44-271 Mg/ha). Variation in OC stocks among nonriverine sites was high in comparison with riverine and mixed geomorphic settings, with sites closer to riverine outflow from the east and south of Moreton Bay having higher stocks than those located on the sand islands in the northwest of the bay. Sediment OC stocks increased with elevation within nonriverine settings, but not in riverine geomorphic settings. Sediment OC stocks did not differ between mangrove and saltmarsh habitats. OC stocks did, however, differ between dominant species across the research area and within geomorphic settings. At the landscape scale, the coastal wetlands of the South East Queensland catchments (17,792 ha) are comprised of approximately 4,100,000-5,200,000 Mg of sediment OC. Comparatively high variation in OC storage between riverine and nonriverine geomorphic settings indicates that the availability of mineral sediments and terrestrial derived OC may exert a strong influence over OC storage potential across

76 FR 28309 - Drawbridge Operation Regulation; Sturgeon Bay Ship Canal, Sturgeon Bay, WI

Science.gov (United States)

2011-05-17

... vehicular traffic congestion would not develop on downtown Sturgeon Bay streets due to unscheduled bridge... schedules during the peak tourist and navigation seasons to provide for the efficient movement of vehicular... between Lake Michigan and Green Bay. The area experiences a significant increase in vehicular and vessel...

Submerged Humid Tropical Karst Landforms Observed By High-Resolution Multibeam Survey in Nagura Bay, Ishigaki Island, Southwestern Japan

Science.gov (United States)

Kan, H.; Urata, K.; Nagao, M.; Hori, N.; Fujita, K.; Yokoyama, Y.; Nakashima, Y.; Ohashi, T.; Goto, K.; Suzuki, A.

2014-12-01

Submerged tropical karst features were discovered in Nagura Bay on Ishigaki Island in the South Ryukyu Islands, Japan. This is the first description of submerged humid tropical karst using multibeam bathymetry. We conducted a broadband multibeam survey in the central area of Nagura Bay (1.85 × 2.7 km) and visualized the high-resolution bathymetric results with a grid size of 1 m over a depth range of 1.6-58.5 m. Various types of humid tropical karst landforms were found to coexist within the bay, including fluviokarst, doline karst, cockpit karst, polygonal karst, uvalas, and mega-dolines. We assume that Nagura Bay was a large karst basin in which older limestone remained submerged, thus preventing corrosion and the accumulation of reef sediments during periods of submersion, whereas the limestone outcropping on land was corroded during multiple interglacial and glacial periods. Based on our bathymetric result together with aerial photographs of the coastal area, we conclude that the submerged karst landscape has likely developed throughout the whole of Nagura Bay, covering an area of ~6 × 5 km. Accordingly, this area hosts the largest submerged karst in Japan. We also observed abundant coral communities during our SCUBA observations. The present marine conditions of Nagura Bay are characterized by low energy (calm sea) and low irradiance owing to the terrestrial influence. Such conditions have been emphasized by the presence of large undulating landforms, which cause decreases in wave intensity and irradiance with depth. These characteristics have acted to establish unique conditions compared to other coral reef areas in the Ryukyu Islands. It may play an important role in supporting the regional coral reef ecosystem.

76 FR 22809 - Safety Zone; Bay Ferry II Maritime Security Exercise; San Francisco Bay, San Francisco, CA

Science.gov (United States)

2011-04-25

... DEPARTMENT OF HOMELAND SECURITY Coast Guard 33 CFR Part 165 [Docket No. USCG-2011-0196] RIN 1625-AA00 Safety Zone; Bay Ferry II Maritime Security Exercise; San Francisco Bay, San Francisco, CA AGENCY... Security Exercise; San Francisco Bay, San Francisco, CA. (a) Location. The limits of this safety zone...

Characterization of Dredged Oyster Shell Deposits at Mobile Bay, Alabama Using Geophysical Methods

Directory of Open Access Journals (Sweden)

Stanley C. Nwokebuihe

2016-12-01

Full Text Available The need for disposing materials dredged from ship channels is a common problem in bays and lagoons. This study is aimed at investigating the suitability of scour features produced by dredging oyster shell deposits in Mobile Bay, Alabama, to dispose excavated channel material. A study area approximately 740 by 280 m lying about 5 km east of Gaillard Island was surveyed using underwater electrical resistivity tomography (UWERT and continuous electrical resistivity profiling (CERP tools. The geophysical survey was conducted with the intent to map scour features created by oyster shell dredging activities in the bay between 1947 and 1982. The geoelectrical surveys show that oyster beds are characterized by high resistivity values greater than 1.1 ohm.m while infilled dredge cuts show lower resistivity, generally from 0.6 to 1.1 ohm.m. The difference in resistivity mainly reflects the lithology and the consolidation of the shallow sediments: consolidated silty clay and sandy sediments rich in oyster shell deposits (with less clay content overlying unconsolidated clayey materials infilling the scours. Results show that most of the infilled dredge cuts are mostly distributed in the north-south direction. Considering that the scours are generally up to 6 m deep across the survey location, it is estimated that about 0.8 million cubic meters of oyster shells and overlying strata were dredged from the survey location.

A Bayes linear Bayes method for estimation of correlated event rates.

Science.gov (United States)

Quigley, John; Wilson, Kevin J; Walls, Lesley; Bedford, Tim

2013-12-01

Typically, full Bayesian estimation of correlated event rates can be computationally challenging since estimators are intractable. When estimation of event rates represents one activity within a larger modeling process, there is an incentive to develop more efficient inference than provided by a full Bayesian model. We develop a new subjective inference method for correlated event rates based on a Bayes linear Bayes model under the assumption that events are generated from a homogeneous Poisson process. To reduce the elicitation burden we introduce homogenization factors to the model and, as an alternative to a subjective prior, an empirical method using the method of moments is developed. Inference under the new method is compared against estimates obtained under a full Bayesian model, which takes a multivariate gamma prior, where the predictive and posterior distributions are derived in terms of well-known functions. The mathematical properties of both models are presented. A simulation study shows that the Bayes linear Bayes inference method and the full Bayesian model provide equally reliable estimates. An illustrative example, motivated by a problem of estimating correlated event rates across different users in a simple supply chain, shows how ignoring the correlation leads to biased estimation of event rates. © 2013 Society for Risk Analysis.

Florida Bay: A history of recent ecological changes

Science.gov (United States)

Fourqurean, J.W.; Robblee, M.B.

1999-01-01

Florida Bay is a unique subtropical estuary at the southern tip of the Florida peninsula. Recent ecological changes (seagrass die-off, algal blooms, increased turbidity) to the Florida Bay ecosystem have focused the attention of the public, commercial interests, scientists, and resource managers on the factors influencing the structure and function of Florida Bay. Restoring Florida Bay to some historic condition is the goal of resource managers, but what is not clear is what an anthropogenically-unaltered Florida Bay would look like. While there is general consensus that human activities have contributed to the changes occurring in the Florida Bay ecosystem, a high degree of natural system variability has made elucidation of the links between human activity and Florida Bay dynamics difficult. Paleoecological analyses, examination of long-term datasets, and directed measurements of aspects of the ecology of Florida Bay all contribute to our understanding of the behavior of the bay, and allow quantification of the magnitude of the recent ecological changes with respect to historical variability of the system.

A method for examining the geospatial distribution of CO2 storage resources applied to the Pre-Punta Gorda Composite and Dollar Bay reservoirs of the South Florida Basin, U.S.A

Science.gov (United States)

Roberts-Ashby, Tina; Brandon N. Ashby,

2016-01-01

This paper demonstrates geospatial modification of the USGS methodology for assessing geologic CO2 storage resources, and was applied to the Pre-Punta Gorda Composite and Dollar Bay reservoirs of the South Florida Basin. The study provides detailed evaluation of porous intervals within these reservoirs and utilizes GIS to evaluate the potential spatial distribution of reservoir parameters and volume of CO2 that can be stored. This study also shows that incorporating spatial variation of parameters using detailed and robust datasets may improve estimates of storage resources when compared to applying uniform values across the study area derived from small datasets, like many assessment methodologies. Geospatially derived estimates of storage resources presented here (Pre-Punta Gorda Composite = 105,570 MtCO2; Dollar Bay = 24,760 MtCO2) were greater than previous assessments, which was largely attributed to the fact that detailed evaluation of these reservoirs resulted in higher estimates of porosity and net-porous thickness, and areas of high porosity and thick net-porous intervals were incorporated into the model, likely increasing the calculated volume of storage space available for CO2 sequestration. The geospatial method for evaluating CO2 storage resources also provides the ability to identify areas that potentially contain higher volumes of storage resources, as well as areas that might be less favorable.

Bird surveys at McKinley Bay and Hutchinson Bay, Northwest Territories, in 1990

Energy Technology Data Exchange (ETDEWEB)

Cornish, B J; Dickson, D L; Dickson, H L

1991-03-01

Monitoring surveys of bird abundance and distribution were conducted in 1990 at McKinley Bay in the Northwest Territories, the site of a winter harbour for drillships and the proposed location for a major year-round support base for oil and gas exploration. Primary objectives of the survey were to determine whether diving duck numbers had changed since the initial phase of the study from 1981-1985, and to provide additional baseline data on natural annual fluctuations in diving duck numbers. Three aerial surveys at each bay were carried out using techniques identical to those in previous years. On 5 August 1990, when survey conditions were considered best of the three surveys, more than twice as many diving ducks were found in McKinley Bay and Hutchinson Bay than on average during the five years of 1981-1985. Old squaw and scooters comprised ca 90% of the diving ducks observed, and both species showed significant increases in numbers. The increase in abundance of diving ducks was likely unrelated to industrial activity in the area since a similar increase occurred in the control area, Hutchinson Bay. Many factors, including both environmental factors such as those affecting nesting success and timing of the moult, and factors related to the survey methods, could be involved in causing the large fluctuations observed. 9 refs., 8 figs., 10 tabs.

Bird surveys at McKinley Bay and Hutchinson Bay, Northwest Territories, in 1990

International Nuclear Information System (INIS)

Cornish, B.J.; Dickson, D.L.; Dickson, H.L.

1991-01-01

Monitoring surveys of bird abundance and distribution were conducted in 1990 at McKinley Bay in the Northwest Territories, the site of a winter harbour for drillships and the proposed location for a major year-round support base for oil and gas exploration. Primary objectives of the survey were to determine whether diving duck numbers had changed since the initial phase of the study from 1981-1985, and to provide additional baseline data on natural annual fluctuations in diving duck numbers. Three aerial surveys at each bay were carried out using techniques identical to those in previous years. On 5 August 1990, when survey conditions were considered best of the three surveys, more than twice as many diving ducks were found in McKinley Bay and Hutchinson Bay than on average during the five years of 1981-1985. Old squaw and scooters comprised ca 90% of the diving ducks observed, and both species showed significant increases in numbers. The increase in abundance of diving ducks was likely unrelated to industrial activity in the area since a similar increase occurred in the control area, Hutchinson Bay. Many factors, including both environmental factors such as those affecting nesting success and timing of the moult, and factors related to the survey methods, could be involved in causing the large fluctuations observed. 9 refs., 8 figs., 10 tabs

78 FR 27126 - East Bay, St. Andrews Bay and the Gulf of Mexico at Tyndall Air Force Base, Florida; Restricted...

Science.gov (United States)

2013-05-09

... DEPARTMENT OF DEFENSE Department of the Army, Corps of Engineers 33 CFR Part 334 East Bay, St. Andrews Bay and the Gulf of Mexico at Tyndall Air Force Base, Florida; Restricted Areas AGENCY: U.S. Army... read as follows: Sec. 334.665 East Bay, St. Andrews Bay and the Gulf of Mexico, Restricted Areas...

Spill management strategy for the Chesapeake Bay

International Nuclear Information System (INIS)

Butler, H.L.; Chapman, R.S.; Johnson, B.H.

1990-01-01

The Chesapeake Bay Program is a unique cooperative effort between state and Federal agencies to restore the health and productivity of America's largest estuary. To assist in addressing specific management issues, a comprehensive three-dimensional, time-varying hydrodynamic and water quality model has ben developed. The Bay modeling strategy will serve as an excellent framework for including submodules to predict the movement, dispersion, and weathering of accidental spills, such as for petroleum products or other chemicals. This paper presents sample results from the Bay application to illustrate the success of the model system in simulating Bay processes. Also, a review of model requirements for successful spill modeling in Chesapeake Bay is presented. Recommendations are given for implementing appropriate spill modules with the Bay model framework and establishing a strategy for model use in addressing management issues

The bay of Cattaro (Kotor school of icon-painting 1680-1860

Directory of Open Access Journals (Sweden)

Stošić Ljiljana

2014-01-01

Full Text Available Relying on post-Byzantine tradition, eleven painters from five generations of the Dimitrijević-Rafailović family, accompanied by Maksim Tujković, painted several thousand icons and several hundred iconostases between the late seventeenth and the second half of the nineteenth century. They worked in major Orthodox Christian monasteries in Montenegro, Kosovo and Metohija, Bosnia and Herzegovina and Dalmatia, but their works can mostly be found in modest village churches in the Bay of Kotor (Cattaro and on the South Adriatic coast. The decoration of these churches was financially supported by the local population headed by elders. Along with a reconstruction of their biographies and a chronological overview of their major works, this paper seeks to trace stylistic changes in the Bay of Kotor school of icon-painting. While simply varying a thematic repertory established in earlier periods, the painters from the Bay of Kotor were gradually introducing new details and themes adopted from Western European Baroque art under indirect influences coming from the monastery of Hilandar, Corfu, Venice and Russia. This process makes this indigenous school of icon-painting, which spanned almost two centuries, comparable to the work of Serbian traditional religious painters (zografs and illuminators active north of the Sava and Danube rivers after the Great Migration of the Serbs (1690. Despite differences between the two, which resulted from different cultural and historical circumstances in which Serbs lived under Ottoman, Venetian and Habsburg rules, similarities in iconography and style, which were inspired by an urge to counteract proselytic pressures, are considerably more important.

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.

measured in the Arabian Sea. Lower respiratin rates in the Bay of Bengal are corroborated by the much weaker north-south gradients in oxygen and total carbon dioxide. These are, however, in conflict with the higher sinking fluxes of organic carbon measured...

Spatial distribution of dinoflagellates from the tropical coastal waters of the South Andaman, India: Implications for coastal pollution monitoring

Digital Repository Service at National Institute of Oceanography (India)

Narale, D.D.; Anil, A.C.

Dinoflagellate community structure from two semi-enclosed areas along the South Andaman region, India, was investigated to assess the anthropogenic impact on coastal water quality. At the densely inhabited Port Blair Bay, the dominance of mixotrophs...

Chlorophyll data collected from the old outfall site in the south sector of Kaneohe Bay, Oahu, Hawaii, February 2001 to May 2004 (NODC Accession 0002805)

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Kaneohe Bay received increasing amounts of sewage from the 1950s through 1977. Most sewage was diverted from the bay in 1977 and early 1978. Data were collected...

POPULATION DYNAMICS OF A COMMERCIAL SPONGE IN BISCAYNE BAY, FLORIDA. (R827453)

Science.gov (United States)

The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

Paleoenvironmental assessment of recent environmental changes in Florida Bay, USA: a biomarker based study

Science.gov (United States)

Xu, Y.; Holmes, C.W.; Jaffe, R.

2007-01-01

The extractable lipid compositions in four Florida Bay cores were determined in order to understand environmental changes over the last 160 years. The most significant environmental change was recorded by oscillations in the amplitude and frequency of biomarkers during the 20th century. Two seagrass molecular proxies (Paq and the C25/C27n-alkan-2-one ratio) reached a maximum post 1900, suggesting that abundant seagrass communities existed during the 20th century. A sharp drop in the Paq value from 0.65 to 0.48 in the central Bay at about 1987 seems to reflect seagrass die-off. The concentrations of microbial biomarkers (C20 HBIs, C25 HBIs and dinosterol) substantially increased after 1950 in the TC, BA and NB cores, reflecting an increase in algal (planktonic organism) primary productivity. However, the RB core presented the highest abundance of C25 HBIs and dinosterol during the period of 1880–1940, suggesting historically large inputs from diatoms and dinoflagellates. A substantial rise in abundance of taraxerol (a specific biomarker of mangroves) from 20 μg/g TOC in the 1830s to 279 μg/g TOC in the l980s is likely a result of increased mangrove primary productivity along the shore of the NE Bay. These changes are most likely the result of hydrological alterations in South Florida.

Atlantic Flyway review: Region IV - Fall 2003

Science.gov (United States)

Robbins, Chandler S.

2004-01-01

We welcome the Eden Mill station in northeastern Maryland to Region IV this year. With three stations reporting their worst year ever, we really need to be refreshed. After a cool and wet July, August was hot and wet in the east. Temperatures in September remained close to normal, but thanks to tropical storms Henri (6-8 Sep) and Isabel (18 Sep), rainfall was excessive in the Chesapeake Bay states. The entire Northeast had cool weather in October, starting with an early freeze on 3 Oct that triggered some good banding days in our region. Precipitation was unusually spotty in October, but plentiful at most of the Region IV stations. November temperatures were consistently well above the norm, starting with a record-breaking 81 ø in Baltimore on the 1st.Four of the five Maryland stations had their best day on 19 or 20 Oct. One might expect some of the Virginia coastal stations, Chincoteague, Kiptopeke, and Back Bay, to share the same best day, but they did not. Three stations reported an increase in birds per net hour this year, while seven had a decline. Summarizing the changes in rank in Table 2, Gray Catbird was the species with the most (5) increases in rank (in excess of decreases), followed by junco (4) and Myrtle Warbler and Swamp Sparrow (3 each). Yellowthroat had the most decreases (5), followed by redstart (3).Myrtle Warbler (4572) was once again the most commonly banded species in Region IV, followed by White-throated Sparrow (1723), Gray Catbird (1349), and Western Palm Warbler (1090). Michelle Davis' station on Key Biscayne is the envy of the rest of us. Her top eight species were all warblers and there was not a Myrtle among them. Imagine having Parula, Prairie, and Worm-eating warblers fighting for sixth place!Not showing among the top ten, however, are other surprises. Several banders commented on Sawwhet Owls and Bicknell's Thrushes. Deanna Dawson banded a Cerulean Warbler at Patuxent. Danny Bystrak caught 138 Swamp Sparrows at Jug Bay. In addition

The extent of tidal influence in the Waccamaw River, South Carolina

Science.gov (United States)

Benjamin Thepaut; John Shelton; Susan Libes; Paul Conrads; Robert Sheehan

2016-01-01

The Waccamaw River Basin is located in the coastal plain and meanders from North Carolina to South Carolina. This tidal black-water river flows parallel to the coast past the cities of Conway and Georgetown, terminating in Winyah Bay. The river is hydrologically connected to the Atlantic Intracoastal Waterway (AIW) and experiences semi-diurnal tides with a range ...

(Crustacea: Branchiura) from a bony fish in Algoa Bay, South Africa

African Journals Online (AJOL)

Department of Zoology, Rand Afrikaans University, P.O. Box 524, Auckland Park, 2006 Republic of South Af"ica. Received J December 1994; accepted 29 September 1995. The new species is characterized by the unique shape of the antennule, antenna and maxilla. In addition, huge scales are present on the mouth tube ...

A Tidally Averaged Sediment-Transport Model for San Francisco Bay, California

Science.gov (United States)

Lionberger, Megan A.; Schoellhamer, David H.

2009-01-01

simulated net sedimentation in the four basins that comprise San Francisco Bay was correct, the simulations incorrectly eroded shallows while channels deposited because model surface-layer boxes span both shallows and channels, and neglect lateral variability of suspended-sediment concentration. Validation with recent (1983-2005) net sedimentation in South San Francisco Bay was poor, perhaps owing to poorly quantified sediment supply, and to invasive species that altered erosion and deposition processes. This demonstrates that deterministically predicting future sedimentation is difficult in this or any estuary for which boundary conditions are not stationary. The model would best be used as a tool for developing past and present sediment budgets, and for creating scenarios of future sedimentation that are compared to one another rather than considered a deterministic prediction.

Short Term Sediment Exchange Between Marshes and Bays Using Beryllium-7 as a Tracer, Fourleague Bay, Louisiana.

Science.gov (United States)

Restreppo, G. A.; Bentley, S. J.; Xu, K.; Wang, J.

2016-12-01

Modern delta models focus on the availability and exchange of coarse sediment as one of the major factors of deltaic growth or decay. Fine-grained sediment exchange within a river's delta is relatively poorly understood, as is the impact that this exchange has on land building and land loss. To better understand the dynamics of fine grain sediment exchange between river mouth, adjacent bays, and marshland, sediment cores from Fourleague Bay, LA, were collected and analyzed for 7Be, a naturally occurring radioisotope that serves as a marker for recently deposited sediment. Time-series push cores were collected every two months at ten sites, five located across a longitudinal transect in the middle bay and five located along adjacent marshes, from May 2015 to May 2016. All sites fall within 11 to 28 km of the Atchafalaya Delta, along a gradient extending towards the open ocean. Cores were extruded in 2 cm intervals, dried, ground, and analyzed via gamma spectrometry for the presence of 7Be. Inventories of 7Be were then calculated and used to determine bimonthly sedimentation rates over the course twelve months. Sediment deposition on the bay floor and marsh surface were then compared to Atchafalaya River discharge, wind speed and direction, and wave action. Preliminary results indicate patterns of initial fluvial sediment transfer from river to bay floor, then bay floor to marsh surface, with decreasing fluvial influence towards the open ocean. Sediment transport from bay to marsh appears to be coupled with meteorological forcing that induces bay-floor sediment resuspension and the flooding of marsh surfaces. This indirect mechanism of fluvial sediment supply to wetland surfaces may extend the region of influence for sediment delivery from man-made river-sediment diversions.

Per- and polyfluoroalkyl substances (PFASs) in San Francisco Bay wildlife: Temporal trends, exposure pathways, and notable presence of precursor compounds.

Science.gov (United States)

Sedlak, Margaret D; Benskin, Jonathan P; Wong, Adam; Grace, Richard; Greig, Denise J

2017-10-01

Concentrations of perfluorooctane sulfonate (PFOS) in San Francisco Bay (SF Bay) wildlife have historically been among the highest reported globally. To track continuing exposures to PFASs and assess the impact of the 2002 phase-out of production of PFOS and related chemicals in the US, nine perfluoroalkyl carboxylic acids (PFCAs; C4-C12), three perfluoroalkyl sulfonic acids (PFSAs; C4, C6, C8) and perfluorooctane sulfonamide (PFOSA, a PFOS precursor) were measured in SF Bay cormorant eggs in 2012 and harbor seal serum sampled between 2009 and 2014. PFOS remained the dominant perfluoroalkyl acid (PFAA) in both cormorant eggs (36.1-466 ng/g) and seals (12.6-796 ng/g) from 2012 and 2014, respectively. Concentrations in seal and bird eggs from the South Bay have declined approximately 70% in both matrices. To elucidate potential pathways of exposure, prey fish, sediments and wastewater effluent were analyzed for PFASs, and in the case of sediment and effluent, a suite of PFAA precursors. PFOS was the dominant PFAA in prey fish and sediment. In effluent, different mixtures of PFAAs were measured, with PFOS, PFHxA, and PFOA detected in the highest concentrations. Polyfluoroalkyl phosphate diesters (PFCA-precursors) were observed at concentrations over an order of magnitude higher than PFCAs in sediment, highlighting their importance as a potential, on-going source of PFCAs to SF Bay wildlife. These findings suggest that the PFOS phase-out has resulted in reduced burdens to wildlife in SF Bay, but that exposure to diverse and incompletely characterized PFASs continues. Copyright © 2017 Elsevier Ltd. All rights reserved.

Drivers of phytoplankton dynamics in old Tampa Bay, FL (USA), a subestuary lagging in ecosystem recovery

Science.gov (United States)

Corcoran, Alina A.; Wolny, Jennifer; Leone, Erin; Ivey, James; Murasko, Susan

2017-02-01

In the past four decades, consistent and coordinated management actions led to the recovery of Tampa Bay, FL (USA) - an estuary that was declared dead in the 1970s. An exception to this success story is Old Tampa Bay, the northernmost subestuary of the system. Compared to the other bay segments, Old Tampa Bay is characterized by poorer water quality and spring and summer blooms of cyanobacteria, picoplankton, diatoms, and the saxitoxin-producing dinoflagellate Pyrodinium bahamense. Together, these blooms contribute to light attenuation and lagging recovery of seagrass beds. Yet, studies of phytoplankton dynamics within Old Tampa Bay have been limited - both in number and in their spatiotemporal resolution. In this study, we used field sampling and continuous monitoring to (1) characterize temporal and spatial variability in phytoplankton biomass and community composition and (2) identify key drivers of the different phytoplankton blooms in Old Tampa Bay. Overall, temporal variability in phytoplankton biomass (using chlorophyll a as a proxy) and community composition surpassed spatial variability of these parameters. We found a base community of small diatoms and flagellates, as well as certain dinoflagellates, that persisted year round in the system. Seasonally, freshwater runoff stimulated phytoplankton growth, specifically that of chlorophytes, cyanobacteria and other dinoflagellates - consistent with predictions based on ecological theory. On shorter time scales, salinity, visibility, and freshwater inflows were important predictors of phytoplankton biomass. With respect to P. bahamense, environmental drivers including salinity, temperature and dissolved nutrient concentrations explained ∼24% of the variability in cell abundance, indicating missing explanatory parameters in our study for this taxon, such as cyst density and location of cyst beds. Spatially, we found differences in community trajectories across north-south and west-east gradients, with the

BOOK REVIEW OF "CHESAPEAKE BAY BLUES: SCIENCE, POLITICS, AND THE STRUGGLE TO SAVE THE BAY"

Science.gov (United States)

This is a book review of "Chesapeake Bay Blues: Science, Politics, and the Struggle to Save the Bay". This book is very well written and provides an easily understandable description of the political challenges faced by those proposing new or more stringent environmental regulat...

Nutrient inputs through submarine groundwater discharge in an embayment: A radon investigation in Daya Bay, China

Science.gov (United States)

Wang, Xuejing; Li, Hailong; Yang, Jinzhong; Zheng, Chunmiao; Zhang, Yan; An, An; Zhang, Meng; Xiao, Kai

2017-08-01

Daya Bay, a semi-closed bay of the South China Sea, is famous for its aquaculture, agriculture and tourism. Although routine environmental investigations in the bay have been conducted since the early 1980s, evaluations of submarine groundwater discharge (SGD), an important process in exchange between groundwater and coastal seawater, and its environmental impacts have never been reported. In this study, naturally occurring radon isotope (222Rn) was measured continuously at two sites (north-west and middle-east sites) and used as a tracer to estimate SGD and associated nutrient inputs into the bay. The SGD rates estimated based on the 222Rn mass balance model were, on average, 28.2 cm/d at north-west site and 30.9 cm/d at middle-east site. The large SGD rate at middle-east site may be due to the large tidal amplitude and the sandy component with high permeability in sediments. The SGD-driven nutrient fluxes, which were calculated as the product of SGD flux and the difference of nutrient concentrations between coastal groundwater and seawater, were 3.28 × 105 mol/d for dissolved nitrates (NO3-N), 5.84 × 103 mol/d for dissolved inorganic phosphorous (DIP), and 8.97 × 105 mol/d for reactive silicate (Si). These nutrient inputs are comparable to or even higher than those supplied by local rivers. In addition, these SGD-driven nutrients have a nitrogen-phosphorous ratio as high as ∼43, which may significantly affect the ecology of coastal waters and lead to frequent occurrence of harmful algal blooms.

Towards a sustainable future in Hudson Bay

International Nuclear Information System (INIS)

Okrainetz, G.

1991-01-01

To date, ca $40-50 billion has been invested in or committed to hydroelectric development on the rivers feeding Hudson Bay. In addition, billions more have been invested in land uses such as forestry and mining within the Hudson Bay drainage basin. However, there has never been a study of the possible impacts on Hudson Bay resulting from this activity. Neither has there been any federal environmental assessment on any of the economic developments that affect Hudson Bay. To fill this gap in knowledge, the Hudson Bay Program was established. The program will not conduct scientific field research but will rather scan the published literature and consult with leading experts in an effort to identify biophysical factors that are likely to be significantly affected by the cumulative influence of hydroelectric and other developments within and outside the region. An annotated bibliography on Hudson Bay has been completed and used to prepare a science overview paper, which will be circulated for comment, revised, and used as the basis for a workshop on cumulative effects in Hudson Bay. Papers will then be commissioned for a second workshop to be held in fall 1993. A unique feature of the program is its integration of traditional ecological knowledge among the Inuit and Cree communities around Hudson Bay with the scientific approach to cumulative impact assessment. One goal of the program is to help these communities bring forward their knowledge in such a way that it can be integrated into the cumulative effects assessment

South Africa

Science.gov (United States)

2002-01-01

contained within South Africa's boundaries. In the upper righthand corner of the image is the Bay of Maputo, where sits Maputo, the capital of Mozambique. Fires are visible in the northeast corner of the image, near Maputo. Just north of Maputo is where the Limpopo River empties into the Indian Ocean. Tracing the Limpopo inland back toward the west, this river defines the northern boundary of South Africa with both Zimbabwe and Botswana. Johannesburg, the commercial capital of South Africa, can be seen as the greyish pixels in the northeastern region of the country. The country's legislative capital, Pretoria, is about 50 miles north of Johannesburg and 250 miles west of Maputo, in the heart of the Northern Province (formerly known as Transvaal). (Image courtesy Jacques Descloitres, MODIS Land Group, NASA Goddard Space Flight Center)

POTENTIAL HAZARDS OF SEDIMENT IN KENDARI BAY, SOUTHEAST SULAWESI

Directory of Open Access Journals (Sweden)

Nur Adi Kristanto

2017-07-01

Full Text Available Kendari bay is located in front of Kendari city. There are two harbors in the inner part of bay which very important to support economic activities such as shipping and passenger transportation. The result of coastal characteristic mapping and physical oceanography survey show various coastal morphology, vegetation, weathering processes, sedimentation, currents, and water depth and sea floor morphology. Kendari bay is an enclosed bay; the area is wide in the inner part and narrow in mouth of bay (outlet, the morphology look like a bottle’s neck. Numerous mouth rivers are concentrate around the bay. The rivers load material from land since erosion on land is intensive enough. There is indication that sediment supplies from land trough river mouth not equivalent with outlet capacity. Sediment load is trapped in the inner bay caused the outlet morphology. So high sediment rate play an important role in the process of shallow of water depth in Kendari bay. This condition make the Kendari bay is a prone area of sediment hazard due to height rate of sedimentary process. Therefore, to anticipate the hazards, precaution should be taken related to the Kendari bay as the center of activities in southeast of Sulawesi. The further survey is needed such as marine geotechnique and on land environmental to collect data, which can be used as database for development planning. Key words: Potential hazard, sediment, Kendari Bay Teluk

MODELING THE 1958 LITUYA BAY MEGA-TSUNAMI, II

Directory of Open Access Journals (Sweden)

Charles L. Mader

2002-01-01

Full Text Available Lituya Bay, Alaska is a T-Shaped bay, 7 miles long and up to 2 miles wide. The two arms at the head of the bay, Gilbert and Crillon Inlets, are part of a trench along the Fairweather Fault. On July 8, 1958, an 7.5 Magnitude earthquake occurred along the Fairweather fault with an epicenter near Lituya Bay.A mega-tsunami wave was generated that washed out trees to a maximum altitude of 520 meters at the entrance of Gilbert Inlet. Much of the rest of the shoreline of the Bay was denuded by the tsunami from 30 to 200 meters altitude.In the previous study it was determined that if the 520 meter high run-up was 50 to 100 meters thick, the observed inundation in the rest of Lituya Bay could be numerically reproduced. It was also concluded that further studies would require full Navier-Stokes modeling similar to those required for asteroid generated tsunami waves.During the Summer of 2000, Hermann Fritz conducted experiments that reproduced the Lituya Bay 1958 event. The laboratory experiments indicated that the 1958 Lituya Bay 524 meter run-up on the spur ridge of Gilbert Inlet could be caused by a landslide impact.The Lituya Bay impact landslide generated tsunami was modeled with the full Navier- Stokes AMR Eulerian compressible hydrodynamic code called SAGE with includes the effect of gravity.

Radionuclides in sediments from Port Phillip Bay, Australia

International Nuclear Information System (INIS)

Smith, J.D.; Tinker, R.A.; Towler, P.H.

1998-01-01

Full text: Sediment cores were collected from two sites in Port Phillip Bay, Australia, in 1994 and 1995. The concentration of 210 Pb and parameters including water content were measured. The sites chosen were near the centre of the bay where fine sediment accumulates, and towards the northern end of the bay closer to the mouth of the Yarra River. The mid-bay sediment had a high water content (about 1.8 g water per g dry sediment) and a supported 210 Pb activity of about 22 mBq per g of dry sediment. The sediments from further north in the bay were more consolidated, with a lower water content (about 0.6 g water per g dry sediment), and had a supported 210 Pb activity of about 6 mBq per g of dry sediment. Unsupported 210 Pb occurred to depths of about 10 cm in the mid-bay sediment and about 20 cm in sediment from further north in the bay. Models incorporating the water and 210 Pb contents of the sediments were used to calculate possible rates of sediment accumulation and mixing. The distribution of other radionuclides was used as an aid in understanding the sediment behaviour in Port Phillip Bay

Novel analyses of long-term data provide a scientific basis for chlorophyll-a thresholds in San Francisco Bay

Science.gov (United States)

Sutula, Martha; Kudela, Raphael; Hagy, James D.; Harding, Lawrence W.; Senn, David; Cloern, James E.; Bricker, Suzanne; Berg, Gry Mine; Beck, Marcus

2017-10-01

San Francisco Bay (SFB), USA, is highly enriched in nitrogen and phosphorus, but has been resistant to the classic symptoms of eutrophication associated with over-production of phytoplankton. Observations in recent years suggest that this resistance may be weakening, shown by: significant increases of chlorophyll-a (chl-a) and decreases of dissolved oxygen (DO), common occurrences of phytoplankton taxa that can form Harmful Algal Blooms (HAB), and algal toxins in water and mussels reaching levels of concern. As a result, managers now ask: what levels of chl-a in SFB constitute tipping points of phytoplankton biomass beyond which water quality will become degraded, requiring significant nutrient reductions to avoid impairments? We analyzed data for DO, phytoplankton species composition, chl-a, and algal toxins to derive quantitative relationships between three indicators (HAB abundance, toxin concentrations, DO) and chl-a. Quantile regressions relating HAB abundance and DO to chl-a were significant, indicating SFB is at increased risk of adverse HAB and low DO levels if chl-a continues to increase. Conditional probability analysis (CPA) showed chl-a of 13 mg m-3 as a "protective" threshold below which probabilities for exceeding alert levels for HAB abundance and toxins were reduced. This threshold was similar to chl-a of 13-16 mg m-3 that would meet a SFB-wide 80% saturation Water Quality Criterion (WQC) for DO. Higher "at risk" chl-a thresholds from 25 to 40 mg m-3 corresponded to 0.5 probability of exceeding alert levels for HAB abundance, and for DO below a WQC of 5.0 mg L-1 designated for lower South Bay (LSB) and South Bay (SB). We submit these thresholds as a basis to assess eutrophication status of SFB and to inform nutrient management actions. This approach is transferrable to other estuaries to derive chl-a thresholds protective against eutrophication.

A novel approach for characterization of polycyclic aromatic hydrocarbon (PAH) pollution patterns in sediments from Guanabara Bay, Rio de Janeiro, Brazil

International Nuclear Information System (INIS)

Christensen, Jan H.; Tomasi, Giorgio; Scofield, Arthur de Lemos; Meniconi, Maria de Fatima Guadalupe

2010-01-01

A novel multivariate method based on principal component analysis of pre-processed sections of chromatograms is used to characterize the complex PAH pollution patterns in sediments from Guanabara Bay, Brazil. Five distinct sources of 3- to 6-ring PAHs could be revealed. The harbour is the most contaminated site in the bay, its plume stretches in a South West to North East direction and the chemical profile indicates mainly pyrogenic sources mixed with a fraction of high-molecular-weight petrogenic PAHs. Rio Sao Joao de Meriti is the second largest source of PAHs, and introduces mainly a fraction of low-molecular-weight petrogenic PAHs from the western region of Rio de Janeiro. The sites close to the ruptured pipeline at the Duque de Caxias Refinery show a distinctive pollution pattern indicating a heavy petroleum fraction. The method also led to the identification of new potential indicator ratios also involving coeluting peaks (e.g., triphenylene and chrysene). - A novel multivariate method is used to characterize the complex PAH pollution patterns in sediments from Guanabara Bay, Brazil.

Spatial and temporal trends in runoff at long-term streamgages within and near the Chesapeake Bay Watershed

Science.gov (United States)

Rice, Karen C.; Hirsch, Robert M.

2012-01-01

Long-term streamflow data within the Chesapeake Bay watershed and surrounding area were analyzed in an attempt to identify trends in streamflow. Data from 30 streamgages near and within the Chesapeake Bay watershed were selected from 1930 through 2010 for analysis. Streamflow data were converted to runoff and trend slopes in percent change per decade were calculated. Trend slopes for three runoff statistics (the 7-day minimum, the mean, and the 1-day maximum) were analyzed annually and seasonally. The slopes also were analyzed both spatially and temporally. The spatial results indicated that trend slopes in the northern half of the watershed were generally greater than those in the southern half. The temporal analysis was done by splitting the 80-year flow record into two subsets; records for 28 streamgages were analyzed for 1930 through 1969 and records for 30 streamgages were analyzed for 1970 through 2010. The mean of the data for all sites for each year were plotted so that the following datasets were analyzed: the 7-day minimum runoff for the north, the 7-day minimum runoff for the south, the mean runoff for the north, the mean runoff for the south, the 1-day maximum runoff for the north, and the 1-day maximum runoff for the south. Results indicated that the period 1930 through 1969 was statistically different from the period 1970 through 2010. For the 7-day minimum runoff and the mean runoff, the latter period had significantly higher streamflow than did the earlier period, although within those two periods no significant linear trends were identified. For the 1-day maximum runoff, no step trend or linear trend could be shown to be statistically significant for the north, although the south showed a mixture of an upward step trend accompanied by linear downtrends within the periods. In no case was a change identified that indicated an increasing rate of change over time, and no general pattern was identified of hydrologic conditions becoming "more extreme

Using Stable Isotopes to Link Nutrient Sources in the Everglades and Biological Sinks in Florida Bay: A Biogeochemical Approach to Evaluate Ecosystem Response to Changing Nutrient Regimes

Science.gov (United States)

Hoare, A. M.; Hollander, D. J.; Heil, C.; Glibert, P.; Murasko, S.; Revilla, M.; Alexander, J.

2005-05-01

Anthropogenic influences in South Florida have led to deterioration of its two major ecosystems, the Everglades wetlands and the Florida Bay estuary. Consequently, the Comprehensive Everglades Restoration Plan has been proposed to restore the Everglades ecosystem; however, restoration efforts will likely exert new ecological changes in the Everglades and ultimately Florida Bay. The success of the Florida Everglades restoration depends on our understanding and ability to predict how regional changes in the distribution and composition of dissolved organic and inorganic nutrients will direct the downstream biogeochemical dynamics of Florida Bay. While the transport of freshwater and nutrients to Florida Bay have been studied, much work remains to directly link nutrient dynamics in Florida Bay to nutrient sources in the Everglades. Our study uses stable C and N isotopic measurements of chemical and biological materials from the Everglades and Florida Bay as part of a multi-proxy approach to link nutrient sources in the Everglades to biological sinks in Florida Bay. Isotopic analyses of dissolved and particulate species of water, aquatic vegetation and sedimentary organic matter show that the watersheds within the Everglades are chemically distinct and that these signatures are also reflected in the bay. A large east-west gradient in both carbon and nitrogen (as much as 10‰ for δ15N POM) reflect differing nutrient sources for each region of Florida Bay and is strongly correlated with upstream sources in the Everglades. Isotopic signatures also reflect seasonal relationships associated with wet and dry periods. High C and N measurements of DOM and POM measurements suggest significant influence from waste water in Canal C-111 in eastern Florida Bay, particularly during the dry season. These observations show that nutrients from the Everglades watersheds enter Florida Bay and are important in controlling biogeochemical processes in the bay. This study proves that

Daya bay reactor neutrino experiment

International Nuclear Information System (INIS)

Cao Jun

2010-01-01

Daya Bay Reactor Neutrino Experiment is a large international collaboration experiment under construction. The experiment aims to precisely determine the neutrino mixing angle θ 13 by detecting the neutrinos produced by the Daya Bay Nuclear Power Plant. θ 13 is one of two unknown fundamental parameters in neutrino mixing. Its magnitude is a roadmap of the future neutrino physics, and very likely related to the puzzle of missing antimatter in our universe. The precise measurement has very important physics significance. The detectors of Daya Bay is under construction now. The full operation is expected in 2011. Three years' data taking will reach the designed the precision, to determine sin 2 2θ 13 to better than 0.01. Daya Bay neutrino detector is an underground large nuclear detector of low background, low energy, and high precision. In this paper, the layout of the experiment, the design and fabrication progress of the detectors, and some highlighted nuclear detecting techniques developed in the detector R and D are introduced. (author)

A multi-year analysis of spillway survival for juvenile salmonids as a function of spill bay operations at McNary Dam, Washington and Oregon, 2004-09

Science.gov (United States)

Adams, Noah S.; Hansel, Hal C.; Perry, Russell W.; Evans, Scott D.

2012-01-01

We analyzed 6 years (2004-09) of passage and survival data collected at McNary Dam to examine how spill bay operations affect survival of juvenile salmonids passing through the spillway at McNary Dam. We also examined the relations between spill bay operations and survival through the juvenile fish bypass in an attempt to determine if survival through the bypass is influenced by spill bay operations. We used a Cormack-Jolly-Seber release-recapture model (CJS model) to determine how the survival of juvenile salmonids passing through McNary Dam relates to spill bay operations. Results of these analyses, while not designed to yield predictive models, can be used to help develop dam-operation strategies that optimize juvenile salmonid survival. For example, increasing total discharge typically had a positive effect on both spillway and bypass survival for all species except sockeye salmon (Oncorhynchus nerka). Likewise, an increase in spill bay discharge improved spillway survival for yearling Chinook salmon (Oncorhynchus tshawytscha), and an increase in spillway discharge positively affected spillway survival for juvenile steelhead (Oncorhynchus mykiss). The strong linear relation between increased spill and increased survival indicates that increasing the amount of water through the spillway is one strategy that could be used to improve spillway survival for yearling Chinook salmon and juvenile steelhead. However, increased spill did not improve spillway survival for subyearling Chinook salmon and sockeye salmon. Our results indicate that a uniform spill pattern would provide the highest spillway survival and bypass survival for subyearling Chinook salmon. Conversely, a predominantly south spill pattern provided the highest spillway survival for yearling Chinook salmon and juvenile steelhead. Although spill pattern was not a factor for spillway survival of sockeye salmon, spill bay operations that optimize passage through the north and south spill bays maximized

226Ra and 228Ra in the mixing zones of the Pee Dee River-Winyah Bay, Yangtze River and Delaware Bay Estuaries

International Nuclear Information System (INIS)

Elsinger, R.J.; Moore, W.S.

1984-01-01

226 Ra and 228 Ra have non-conservative excess concentrations in the mixing zones of the Pee Dee River-Winyah Bay estuary, the Yangtze River estuary, and the Delaware Bay estuary. Laboratory experiments, using Pee Dee River sediment, indicate desorption of 226 Ra to increase with increasing salinities up to 20 per mille. In Winyah Bay desorption from river-borne sediments could contribute almost all of the increases for both isotopes. Desorption adds only a portion of the excess 228 Ra measured in the Yangtze River and adjacent Shelf waters and Delaware Bay. In the Yangtze River the mixing zone extends over a considerable portion of the Continental Shelf where 228 Ra is added to the water column by diffusion from bottom sediments, while 226 Ra concentrations decrease from dilution. Diffusion of 228 Ra from bottom sediments in Delaware Bay primarily occurs in the upper part of the bay ( 228 Ra of 0.33 dpm cm -2 year was determined for Delaware Bay. (author)

Diurnal variation in rates of calcification and carbonate sediment dissolution in Florida Bay

Science.gov (United States)

Yates, K.K.; Halley, R.B.

2006-01-01

Water quality and circulation in Florida Bay (a shallow, subtropical estuary in south Florida) are highly dependent upon the development and evolution of carbonate mud banks distributed throughout the Bay. Predicting the effect of natural and anthropogenic perturbations on carbonate sedimentation requires an understanding of annual, seasonal, and daily variations in the biogenic and inorganic processes affecting carbonate sediment precipitation and dissolution. In this study, net calcification rates were measured over diurnal cycles on 27 d during summer and winter from 1999 to 2003 on mud banks and four representative substrate types located within basins between mud banks. Substrate types that were measured in basins include seagrass beds of sparse and intermediate density Thalassia sp., mud bottom, and hard bottom communities. Changes in total alkalinity were used as a proxy for calcification and dissolution. On 22 d (81%), diurnal variation in rates of net calcification was observed. The highest rates of net carbonate sediment production (or lowest rates of net dissolution) generally occurred during daylight hours and ranged from 2.900 to -0.410 g CaCO3 m-2 d-1. The lowest rates of carbonate sediment production (or net sediment dissolution) occurred at night and ranged from 0.210 to -1.900 g CaCO3 m -2 night-1. During typical diurnal cycles, dissolution during the night consumed an average of 29% of sediment produced during the day on banks and 68% of sediment produced during the day in basins. Net sediment dissolution also occurred during daylight, but only when there was total cloud cover, high turbidity, or hypersalinity. Diurnal variation in calcification and dissolution in surface waters and surface sediments of Florida Bay is linked to cycling of carbon dioxide through photosynthesis and respiration. Estimation of long-term sediment accumulation rates from diurnal rates of carbonate sediment production measured in this study indicates an overall average

Ecology of Syllidae (Annelida: Polychaeta from shallow rocky environments in the Cantabrian Sea (South Bay of Biscay

Directory of Open Access Journals (Sweden)

Alberto Serrano

2006-12-01

Full Text Available The syllids inhabiting 12 hard bottom macrobenthic habitats were studied. A total of 38 species belonging to 19 genera were identified. Differences in density, species richness, and diversity among habitats were analysed, as well as the relationships between these ecological parameters and depth range, slope and in-bay/out-bay gradient. The effect of environmental variables on syllid distribution was studied using canonical ordination. A high faunistic homogeneity has been found, since all biotopes were dominated by a low number of eurytopic species (Syllis armillaris, S. gracilis and S. variegata. Habitat complexity, determined by physical disturbance, is the main structuring factor in syllid populations. Biotopes with the highest structural complexity displayed a high number of companion species increasing ecological indices and denoting a well-structured habitat. On the other hand, communities such as in upper intertidal habitats, mainly controlled by physical environmental variables, showed a poorer syllid fauna, dominated by ubiquitious species and a few stenotopic species well-adapted to those environments. However, this is not the case in some other intertidal biotopes, such as in Corallina, whose tangled structure prevents drying and provides shelter from predation, allowing a richer and more diverse syllid fauna.

Occurrence of potentially pathogenic Vibrio in oysters (Crassostrea gigas) and waters from bivalve mollusk cultivations in the South Bay of Santa Catarina.

Science.gov (United States)

Ramos, Roberta Juliano; Miotto, Letícia Adélia; Miotto, Marília; Silveira Junior, Nelson; Cirolini, Andréia; Silva, Helen Silvestre da; Rodrigues, Dália dos Prazeres; Vieira, Cleide Rosana Werneck

2014-01-01

This research aimed to identify and quantify potentially pathogenic Vibrio from different cultivations of bivalve shellfish in the State of Santa Catarina, Brazil, and water regions in the South Bay, as well as correlate the incidence of these microorganisms with the physicochemical parameters of marine waters. Between October 2008 and March 2009, 60 oyster and seawater samples were collected from six regions of bivalve mollusk cultivation, and these samples were submitted for Vibrio counts. Twenty-nine (48.3%) oyster samples were revealed to be contaminated with one or more Vibrio species. The Vibrio parahaemolyticus and Vibrio vulnificus counts in the samples ranged from oyster and from oyster, respectively. Of the 60 seawater samples analyzed, 44 (73.3%) showed signs of contamination with one or more vibrio species. The counts of V. parahaemolyticus and V. vulnificus in the samples ranged from < 0.3 log10 MPN·100mL(-1) to 1.7 log10MPN·100mL(-1) seawater and from < 0.3 log10 MPN·100mL(-1) to 2.0 log10 MPN·100mL(-1) seawater, respectively. A positive correlation between V. vulnificus counts and the seawater temperature as well as a negative correlation between the V. parahaemolyticus counts and salinity were observed. The results suggest the need to implement strategies to prevent vibrio diseases from being transmitted by the consumption of contaminated bivalve shellfish.

First Investigation of Microbial Community Composition in the Bridge (Gadeok Channel) between the Jinhae-Masan Bay and the South Sea of Korea

Science.gov (United States)

Lee, Jiyoung; Lim, Jae-Hyun; Park, Junhyung; Youn, Seok-Hyun; Oh, Hyun-Ju; Kim, Ju-Hyoung; Kim, Myung Kyum; Cho, Hyeyoun; Yoon, Joo-Eun; Kim, Soyeon; Markkandan, Kesavan; Park, Ki-Tae; Kim, Il-Nam

2018-02-01

Microbial community composition varies based on seasonal dynamics (summer: strongly stratified water column; autumn: weakly stratified water column; winter: vertically homogeneous water column) and vertical distributions (surface, middle, and bottom depths) in the Gadeok Channel, which is the primary passage to exchange waters and materials between the Jinhae-Masan Bay and the South Sea waters. The microbial community composition was analyzed from June to December 2016 using 16S rRNA gene sequencing. The community was dominated by the phyla Proteobacteria (45%), Bacteroidetes (18%), Cyanobacteria (15%), Verrucomicrobia (6%), and Actinobacteria (6%). Alphaproteobacteria (29%) was the most abundant microbial class, followed by Flavobacteria (15%) and Gammaproteobacteria (15%) in all samples. The composition of the microbial communities was found to vary vertically and seasonally. The orders Flavobacteriales and Stramenopiles showed opposing seasonal patterns; Flavobacteriales was more abundant in August and December while Stramenopiles showed high abundance in June and October at all depths. The genus Synechococcus reached extremely high abundance (14%) in the June surface water column, but was much less abundant in December water columns. Clustering analysis showed that there was a difference in the microbial community composition pattern between the strongly stratified season and well-mixed season. These results indicate that the seasonal dynamics of physicochemical and hydrologic conditions throughout the water column are important parameters in shaping the microbial community composition in the Gadeok Channel.

The Neoglacial landscape and human history of Glacier Bay, Glacier Bay National Park and Preserve, southeast Alaska, USA

Science.gov (United States)

Connor, C.; Streveler, G.; Post, A.; Monteith, D.; Howell, W.

2009-01-01

The Neoglacial landscape of the Huna Tlingit homeland in Glacier Bay is recreated through new interpretations of the lower Bay's fjordal geomorphology, late Quaternary geology and its ethnographic landscape. Geological interpretation is enhanced by 38 radiocarbon dates compiled from published and unpublished sources, as well as 15 newly dated samples. Neoglacial changes in ice positions, outwash and lake extents are reconstructed for c. 5500?????"200 cal. yr ago, and portrayed as a set of three landscapes at 1600?????"1000, 500?????"300 and 300?????"200 cal. yr ago. This history reveals episodic ice advance towards the Bay mouth, transforming it from a fjordal seascape into a terrestrial environment dominated by glacier outwash sediments and ice-marginal lake features. This extensive outwash plain was building in lower Glacier Bay by at least 1600 cal. yr ago, and had filled the lower bay by 500 cal. yr ago. The geologic landscape evokes the human-described landscape found in the ethnographic literature. Neoglacial climate and landscape dynamism created difficult but endurable environmental conditions for the Huna Tlingit people living there. Choosing to cope with environmental hardship was perhaps preferable to the more severely deteriorating conditions outside of the Bay as well as conflicts with competing groups. The central portion of the outwash plain persisted until it was overridden by ice moving into Icy Strait between AD 1724?????"1794. This final ice advance was very abrupt after a prolonged still-stand, evicting the Huna Tlingit from their Glacier Bay homeland. ?? 2009 SAGE Publications.

Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

Energy Technology Data Exchange (ETDEWEB)

Blazer, Vicki S., E-mail: Vblazer@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Pinkney, Alfred E., E-mail: Fred_Pinkeny@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Jenkins, Jill A., E-mail: jenkinsj@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Iwanowicz, Luke R., E-mail: Liwanowicz@usgs.gov [U.S. Geological Survey, National Fish Health Research Laboratory, Leetown Science Center, 11649 Leetown Road, Kearneysville, WV 25430 (United States); Minkkinen, Steven, E-mail: steve_minkkinen@fws.gov [U.S. Fish and Wildlife Service, Chesapeake Bay Field Office, 177 Admiral Cochrane Drive, Annapolis, MD 21401 (United States); Draugelis-Dale, Rassa O., E-mail: daler@usgs.gov [U.S. Geological Survey, National Wetlands Research Center, 700 Cajundome Blvd., Lafayette, LA 70506 (United States); Uphoff, James H., E-mail: juphoff@dnr.state.md.us [Maryland Department of Natural Resources, Fisheries Service, Cooperative Oxford Laboratory, 904 South Morris Street, Oxford, MD 21654 (United States)

2013-03-01

Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. - Highlights: ► Reduced recruitment of yellow perch has occurred in urban tributaries of Chesapeake Bay. ► We compared reproductive health biomarkers in perch from two urban, one developing, two less developed

Reproductive health of yellow perch Perca flavescens in selected tributaries of the Chesapeake Bay

International Nuclear Information System (INIS)

Blazer, Vicki S.; Pinkney, Alfred E.; Jenkins, Jill A.; Iwanowicz, Luke R.; Minkkinen, Steven; Draugelis-Dale, Rassa O.; Uphoff, James H.

2013-01-01

Reduced recruitment of yellow perch has been noted for a number of years in certain urbanized watersheds (South and Severn Rivers) of the Chesapeake Bay. Other rapidly developing watersheds such as Mattawoman Creek are more recently showing evidence of reduced recruitment of anadromous fishes. In this study, we used a battery of biomarkers to better document the reproductive health of adult yellow perch collected during spring spawning in 2007–2009. Perch were collected in the South and Severn Rivers, Mattawoman Creek and the less developed Choptank and Allen's Fresh watersheds for comparison. Gonadosomatic indices, plasma reproductive hormone concentrations, plasma vitellogenin concentrations and gonad histology were evaluated in mature perch of both sexes. In addition, sperm quantity (cell counts) and quality (total and progressive motility, spermatogenic stage and DNA integrity), were measured in male perch. Many of these biomarkers varied annually and spatially, with some interesting statistical results and trends. Male perch from the Choptank and Allen's Fresh had generally higher sperm counts. In 2008 counts were significantly lower in the perch from the Severn when compared to other sites. The major microscopic gonadal abnormality in males was the proliferation of putative Leydig cells, observed in testes from Severn and less commonly, Mattawoman Creek perch. Observations that could significantly impact egg viability were an apparent lack of final maturation, abnormal yolk and thin, irregular zona pellucida. These were observed primarily in ovaries from Severn, South and less commonly Mattawoman Creek perch. The potential association of these observations with urbanization, impervious surface and chemical contaminants is discussed. - Highlights: ► Reduced recruitment of yellow perch has occurred in urban tributaries of Chesapeake Bay. ► We compared reproductive health biomarkers in perch from two urban, one developing, two less developed watersheds. �

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

Simulation of the water-table altitude in the Biscayne Aquifer, southern Dade County, Florida, water years 1945-89

Science.gov (United States)

Merritt, M.L.

1995-01-01

A digital model of the flow system in the highly permeable surficial aquifer of southern Dade County, Florida, was constructed for the purposes of better understanding processes that influence the flow system and of supporting the construction of a subregional model of the transport of brackish water from a flowing artesian well. Problems that needed resolution in this endeavor included the development of methods to represent the influence of flowing surface water in seasonally inundated wetlands and the influence of a network of controlled canals developed in stages during the simulation time period (water years 1945-89). An additional problem was the general lack of natural aquifer boundaries near the boundaries of the study area. The model construction was based on a conceptual description of the Biscayne aquifer developed from the results of previous U.S. Geological Survey investigations. Modifications were made to an existing three- dimensional finite-difference simulator of ground- water flow to enable an upper layer of the grid to represent seasonally occurring overland sheetflow in a series of transient simulations of water levels from 1945 to 1989. A rewetting procedure was developed for the simulator that permitted resaturation of cells in this layer when the wet season recurred. An "equivalent hydraulic conductivity" coefficient was assigned to the overland flow layer that was analogous, subject to various approximations, to the use of the Manning equation. The surficial semiconfining peat and marl layers, levees, canals, and control structures were also represented as part of the model grid with the appropriate choices of hydraulic coefficient values. For most of the Biscayne aquifer grid cells, the value assigned to hydraulic conductivity for model calibration was 30,000 feet per day and the value assigned to porosity was 20 percent. Boundary conditions were specified near data sites having long-term records of surface-water stages or water

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.

Chesapeake Bay under stress

Science.gov (United States)

According to extensive data obtained over its 13,000 km of shoreline, the Chesapeake Bay has been suffering a major, indeed unprecedented, reduction in submerged vegetation. Chesapeake Bay is alone in experiencing decline in submerged vegetation. Other estuary systems on the east coast of the United States are not so affected. These alarming results were obtained by the synthesis of the findings of numerous individual groups in addition to large consortium projects on the Chesapeake done over the past decade. R. J. Orth and R. A. Moore of the Virginia Institute of Marine Science pointed to the problem of the severe decline of submerged grasses on the Bay and along its tributaries. In a recent report, Orth and Moore note: “The decline, which began in the 1960's and accelerated in the 1970's, has affected all species in all areas. Many major river systems are now totally devoid of any rooted vegetation” (Science, 222, 51-53, 1983).

Foraminifera Population from South Africa Coast Line (Indian and Atlantic Oceans

Directory of Open Access Journals (Sweden)

Engin Meriç

2014-11-01

Full Text Available Cape Town is the second-largest city of the Republic of South Africa. Research is conducted in 3 different stations: Maori Bay, which lies in the southwest of Cape Town, and Pyramid Rock and Partridge Points which lies in the False Bay, southeast part of Cape Town. Samples are taken from young sediments at 10.00 and 20.00 m depths, and collected by scuba-diving method. The aim of the study is to investigate the living benthic foraminifera assemblages in the Atlantic Ocean, and to compare these assemblages with the southeastern part of the Atlantic Ocean, the Arabian Sea, Indian Ocean and Western Pacific assemblages. Moreover, the aim of the study is to determine whether there are any benthic foraminifera forms reaching to the Mediterranean from Pacific Ocean, Indian Ocean or Red Sea via Suez Channel.

Toxic phytoplankton in San Francisco Bay

Science.gov (United States)

Rodgers, Kristine M.; Garrison, David L.; Cloern, James E.

1996-01-01

The Regional Monitoring Program (RMP) was conceived and designed to document the changing distribution and effects of trace substances in San Francisco Bay, with focus on toxic contaminants that have become enriched by human inputs. However, coastal ecosystems like San Francisco Bay also have potential sources of naturally-produced toxic substances that can disrupt food webs and, under extreme circumstances, become threats to public health. The most prevalent source of natural toxins is from blooms of algal species that can synthesize metabolites that are toxic to invertebrates or vertebrates. Although San Francisco Bay is nutrient-rich, it has so far apparently been immune from the epidemic of harmful algal blooms in the world’s nutrient-enriched coastal waters. This absence of acute harmful blooms does not imply that San Francisco Bay has unique features that preclude toxic blooms. No sampling program has been implemented to document the occurrence of toxin-producing algae in San Francisco Bay, so it is difficult to judge the likelihood of such events in the future. This issue is directly relevant to the goals of RMP because harmful species of phytoplankton have the potential to disrupt ecosystem processes that support animal populations, cause severe illness or death in humans, and confound the outcomes of toxicity bioassays such as those included in the RMP. Our purpose here is to utilize existing data on the phytoplankton community of San Francisco Bay to provide a provisional statement about the occurrence, distribution, and potential threats of harmful algae in this Estuary.

Potential effects of alterations to the hydrologic system on the distribution of salinity in the Biscayne aquifer in Broward County, Florida

Science.gov (United States)

Hughes, Joseph D.; Sifuentes, Dorothy F.; White, Jeremy T.

2016-03-15

To address concerns about the effects of water-resource management practices and rising sea level on saltwater intrusion, the U.S. Geological Survey in cooperation with the Broward County Environmental Planning and Community Resilience Division, initiated a study to examine causes of saltwater intrusion and predict the effects of future alterations to the hydrologic system on salinity distribution in eastern Broward County, Florida. A three-dimensional, variable-density solute-transport model was calibrated to conditions from 1970 to 2012, the period for which data are most complete and reliable, and was used to simulate historical conditions from 1950 to 2012. These types of models are typically difficult to calibrate by matching to observed groundwater salinities because of spatial variability in aquifer properties that are unknown, and natural and anthropogenic processes that are complex and unknown; therefore, the primary goal was to reproduce major trends and locally generalized distributions of salinity in the Biscayne aquifer. The methods used in this study are relatively new, and results will provide transferable techniques for protecting groundwater resources and maximizing groundwater availability in coastal areas. The model was used to (1) evaluate the sensitivity of the salinity distribution in groundwater to sea-level rise and groundwater pumping, and (2) simulate the potential effects of increases in pumping, variable rates of sea-level rise, movement of a salinity control structure, and use of drainage recharge wells on the future distribution of salinity in the aquifer.

Public health assessment for Munisport landfill, North Miami, Dade County, Florida, Region 4. CERCLIS No. FLD084535442. Final report

International Nuclear Information System (INIS)

1993-01-01

The Munisport Landfill site is an inactive landfill in, and owned by, the City of North Miami, Florida. The site is an urban area adjacent to the Oleta River Recreational Area, a state mangrove preserve, and Biscayne Bay. Soil, sediments, surface water, and ground water are contaminated. The authors selected ammonia, benzene, di(2-ethylhexyl)phthalate, cadmium, carbon disulfide, chloromethane, coliform bacteria, dieldrin, lead, methylene chloride, pentachlorophenol, polychlorinated biphenyls (PCBs), styrene, vanadium, and zinc as contaminants of concern. Accidentally ingesting contaminated soil and surface water, and breathing contaminated smoke are completed human exposure pathways. Children who swam in the landfill lakes risked bacterial and viral infections. Based on the available data, the authors categorize the Munisport Landfill site as an indeterminate public health hazard

Heavy metals in superficial sediment of Algiers Bay

International Nuclear Information System (INIS)

Benamar, M.A.; Toumert, C.L.; Chaouch, L.; Bacha, L.; Tobbeche, S.

1996-01-01

Sediment samples were collected in 33 stations from the bay of Algiers for the potential sources of pollution. the analyses were made x-ray fluorescence (XRF) and atomic absorption spectrometry (AAS) the results give information about level of concentrations morphology of the bay (funnel form of bay). only Co,Mn,Fe, and Cd present a particular repartition (unrelated to the sedimentary facies). the level pollution bu heavy metals of the bottom sediments in algiers bay have been compared with those of Surkouk considered as a region with low anthropogenic activities

Polycyclic aromatic hydrocarbons in sediments and mussels of Corral Bay, south central Chile.

Science.gov (United States)

Palma-Fleming, Hernan; P, Adalberto J Asencio; Gutierrez, Elena

2004-03-01

PAHs were measured in sediments and mussels (Mytilus chilensis) from Carboneros and Puerto Claro, located in Corral Bay, Valdivia. According to the ratio of phenanthrene/anthracene and fluoranthene/pyrene concentrations, these sites are medium polluted with PAHs originating mainly from pyrolytic sources. Fluoranthene was the major component measured in mussels (3.1-390 ng g(-1) dry weight) and sediments (6.9-74.1 ng g(-1) dry weight). In general, mussels were mainly exposed to the dissolved fraction of the lower molecular weight PAHs (tri- and tetra-aromatics) while the higher molecular ring systems (penta- and hexa-aromatics) were more bioavailable to sediments. Mussel PAHs content was relatively constant, with the exception of the 1999 summer season (March), when higher concentration values were found in both sites; however, PAHs residues in sediments showed a temporal variation.

Hierarchical mixtures of naive Bayes classifiers

NARCIS (Netherlands)

Wiering, M.A.

2002-01-01

Naive Bayes classifiers tend to perform very well on a large number of problem domains, although their representation power is quite limited compared to more sophisticated machine learning algorithms. In this pa- per we study combining multiple naive Bayes classifiers by using the hierar- chical

Early Holocene estuary development of the Hesselø Bay area, southern Kattegat, Denmark and its implication for Ancylus Lake drainage

DEFF Research Database (Denmark)

Bendixen, Carina; Boldreel, Lars Ole; Jensen, Jørn Bo

2017-01-01

environment and a description of coastal processes associated with a river outlet into the bay are presented. Weichselian glacial deposits form the lowermost interpreted unit, covered by late glacial (LG) and postglacial (PG, Holocene) sediments. A funnel-shaped estuary existed at the mouth of channels......High-resolution shallow seismic data, sediment core information, radiocarbon dating and sequence stratigraphy have been used to interpret the late glacial to early Holocene geological evolution of Hesselø Bay in the southern Kattegat, Denmark. A reconstruction of the early Holocene coastal...... in the period 10.3–9.2 cal. ka BP; the channels drained water from south to north. The early PG is characterised by estuarine and coastal deposits. The early Holocene bars that developed in the estuary are preserved as morphological features on the present-day seabed, possibly as a result of rapid relative sea...

Whose Bay Street? Competing Narratives of Nassau's City Centre

Directory of Open Access Journals (Sweden)

Nona Patara Martin

2009-05-01

Full Text Available Bay Street has always been at the centre of commercial, cultural and political life in the Bahama Islands. It also acts as a gateway for millions of tourists who come to Nassau, the Bahamian capital, via cruise ships every year. Not surprisingly, Bahamians and non-Bahamians have widely divergent impressions of Bay Street. The need to accommodate the tourists who are critical to the Bahamian economy has meant that Bay Street, despite its deep social significance for Bahamians, has increasingly become a tourist space. With reference to the ‘sense of place’ and place attachment literature, this paper traces the transformation of Bay Street and attempts to tease out the most obvious tensions between the Bay Street that Bahamians experience and Bay Street as a port of call.

Diatom paleoecology Pass Key core 37, Everglades National Park, Florida Bay

Science.gov (United States)

Pyle, Laura; Cooper, S.R.; Huvane, J.K.

1998-01-01

During the 20th century, there have been large-scale anthropogenic modifications to the South Florida ecosystem. The effects of these changes on Florida Bay and its biological communities are currently of political and scientific interest. This study is part of a larger effort to reconstruct the history of environmental changes in the bay, using paleoecological techniques. We are using diatom indicators preserved in Florida Bay sediments to infer long-term water quality, productivity, nutrient, and salinity changes. We are also obtaining information concerning the natural variability of the ecosystem. Diatoms are microscopic algae, the remains of which are generally well preserved in sediments, and their distributions are closely linked to water quality. Diatoms were extracted from a 70-cm sediment core collected from the Pass Key mudbank of Florida Bay by the U.S. Geological Survey. Between 300-500 diatom valves from each of 15 core samples were identified and counted. Estimates of absolute abundance, species richness, Shannon-Wiener diversity, and centric:pennate ratios were calculated for each sample that was counted. Information on the ecology of the diatom species is presented, and changes in diatom community composition are evaluated. Samples contained an average of four million diatom valves per gram of sediment. Major changes in the diatom community are evident down core. These include increases in the percent abundance of marine diatoms in the time period represented by the core, probably the result of increasing salinity at Pass Key. Benthic diatoms become less abundant in the top half of the core. This may be related to a number of factors including the die-off of sea grass beds or increased turbidity of the water column. Once the chronology of the Pass Key core 37 is established, these down-core changes can be related to historical events and compared with other indicators in the sedimentary record that are currently being investigated by U.S Geological

Fecal indicator bacteria at Havana Bay

International Nuclear Information System (INIS)

Lopez Perez, Lisse; Gomez D'Angelo, Yamiris; Beltran Gonzalez, Jesus; Alvarez Valiente, Reinaldo

2013-01-01

Aims: Fecal indicator bacteria concentrations were evaluated in Havana Bay. Methods: Concentrations of traditional fecal indicator bacteria were calculated between April 2010 and February 2011, by MPN methods. Concentrations of thermo tolerant coliform (CTT), Escherichia coli, fecal streptococci (EF), intestinal enterococci (ENT) in seawater, and Clostridium perfringens in sediment surface, were determined. Results: CTT and E. coli levels were far above Cuban water quality standard for indirect contact with water, showing the negative influence of sewage and rivers on the bay. The EF and ENT were measured during sewage spills at the discharge site and they were suitable indicators of fecal contamination, but these indicators didn't show the same behavior in other selected sites. This result comes from its well-known inactivation by solar light in tropical zones and the presumable presence of humid acids in the waters of the bay. Conclusion: Fecal indicator bacteria and its statistical relationships reflect recent and chronic fecal contamination at the bay and near shores.

Rapid sedimentation of iron oxyhydroxides in an active hydrothermal shallow semi-enclosed bay at Satsuma Iwo-Jima Island, Kagoshima, Japan

Science.gov (United States)

Kiyokawa, Shoichi; Ueshiba, Takuya

2015-04-01

Hydrothermal activity is common in the fishing port of Nagahama Bay, a small semi-enclosed bay located on the southwest coast of Satsuma Iwo-Jima Island (38 km south of Kyushu Island, Japan). The bay contains red-brown iron oxyhydroxides and thick deposits of sediment. In this work, the high concentration and sedimentation rates of oxyhydroxide in this bay were studied and the sedimentary history was reconstructed. Since dredging work in 1998, a thickness of 1.0-1.5 m of iron oxyhydroxide-rich sediments has accumulated on the floor of the bay. To estimate the volume of iron oxyhydroxide sediments and the amount discharged from hydrothermal vents, sediment traps were operated for several years and 13 sedimentary core samples were collected to reconstruct the 10-year sedimentary history of Nagahama Bay. To confirm the timing of sedimentary events, the core data were compared with meteorological records obtained on the island, and the ages of characteristic key beds were thus identified. The sedimentation rate of iron oxyhydroxide mud was calculated, after correcting for sediment input from other sources. The sediments in the 13 cores from Nagahama Bay consist mainly of iron oxyhydroxide mud, three thick tephra beds, and a topmost thick sandy mud bed. Heavy rainfall events in 2000, 2001, 2002, and 2004-2005 coincide with tephra beds, which were reworked from Iwo-Dake ash deposits to form tephra-rich sediment. Strong typhoon events with gigantic waves transported outer-ocean-floor sediments and supplied quartz, cristobalite, tridymite, and albite sands to Nagahama Bay. These materials were redeposited together with bay sediments as the sandy mud bed. Based on the results from the sediment traps and cores, it is estimated that the iron oxyhydroxide mud accumulated in the bay at the relatively rapid rate of 33.3 cm/year (from traps) and 2.8-4.9 cm/year (from cores). The pore water contents within the sediment trap and core sediments are 73%-82% and 47%-67%, respectively

Three new species of Diascia (Scrophulariaceae from the Western Cape, South Africa

Directory of Open Access Journals (Sweden)

K. E. Steiner

2009-08-01

Full Text Available Three new annual species of Diascia Link & Otto are described from the Western Cape Province of South Africa. D. collina is characterized by greyish magenta flowers with two divergent yellow sacs containing oil-secreting trichomes. It is restricted to granite outcrops in the vicinity of Saldanha Bay, from the West Coast National Park and Langebaan north to Vredenburg. D. pusilla is closely related to D. collina. but differs from that species in having smaller flowers with shorter, ± parallel sacs, and posticous filaments that lack a protuberance where they bend sharply backwards towards the upper lip. It occurs in grey to whitish sands usually near seasonally moist or wet areas. It has not been found more than 35 km from the coast and ranges from Modderrivier, south o f Darling, north to Lambert’s Bay. D. appendiculata is related to D. diffusa (Thunb. Benth. and is characterized by having small, mainly reddish lilac to greyish magenta flowers, two shallow depressions in the corolla tube at the base of the upper lip, and posticous filaments with sterile appendages. It is known from only six localities in the general vicinity of Citrusdal and occurs in fynbos vegetation on lower mountain slopes or flats, in loose alluvial sands derived from Table Mountain Sandstone.

Origins and delineation of saltwater intrusion in the Biscayne aquifer and changes in the distribution of saltwater in Miami-Dade County, Florida

Science.gov (United States)

Prinos, Scott T.; Wacker, Michael A.; Cunningham, Kevin J.; Fitterman, David V.

2014-01-01

Intrusion of saltwater into parts of the shallow karst Biscayne aquifer is a major concern for the 2.5 million residents of Miami-Dade County that rely on this aquifer as their primary drinking water supply. Saltwater intrusion of this aquifer began when the Everglades were drained to provide dry land for urban development and agriculture. The reduction in water levels caused by this drainage, combined with periodic droughts, allowed saltwater to flow inland along the base of the aquifer and to seep directly into the aquifer from the canals. The approximate inland extent of saltwater was last mapped in 1995. An examination of the inland extent of saltwater and the sources of saltwater in the aquifer was completed during 2008–2011 by using (1) all available salinity information, (2) time-series electromagnetic induction log datasets from 35 wells, (3) time-domain electromagnetic soundings collected at 79 locations, (4) a helicopter electromagnetic survey done during 2001 that was processed, calibrated, and published during the study, (5) cores and geophysical logs collected from 8 sites for stratigraphic analysis, (6) 8 new water-quality monitoring wells, and (7) analyses of 69 geochemical samples. The results of the study indicate that as of 2011 approximately 1,200 square kilometers (km2) of the mainland part of the Biscayne aquifer were intruded by saltwater. The saltwater front was mapped farther inland than it was in 1995 in eight areas totaling about 24.1 km2. In many of these areas, analyses indicated that saltwater had encroached along the base of the aquifer. The saltwater front was mapped closer to the coast than it was in 1995 in four areas totaling approximately 6.2 km2. The changes in the mapped extent of saltwater resulted from improved spatial information, actual movement of the saltwater front, or a combination of both. Salinity monitoring in some of the canals in Miami-Dade County between 1988 and 2010 indicated influxes of saltwater, with maximum

Heme oxygenase-1 mediates BAY 11-7085 induced ferroptosis.

Science.gov (United States)

Chang, Ling-Chu; Chiang, Shih-Kai; Chen, Shuen-Ei; Yu, Yung-Luen; Chou, Ruey-Hwang; Chang, Wei-Chao

2018-03-01

Ferroptosis is a form of oxidative cell death and has become a chemotherapeutic target for cancer treatment. BAY 11-7085 (BAY), which is a well-known IκBα inhibitor, suppressed viability in cancer cells via induction of ferroptotic death in an NF-κB-independent manner. Reactive oxygen species scavenging, relief of lipid peroxidation, replenishment of glutathione and thiol-containing agents, as well as iron chelation, rescued BAY-induced cell death. BAY upregulated a variety of Nrf2 target genes related to redox regulation, particularly heme oxygenase-1 (HO-1). Studies with specific inhibitors and shRNA interventions suggested that the hierarchy of induction is Nrf2-SLC7A11-HO-1. SLC7A11 inhibition by erastin, sulfasalazine, or shRNA interference sensitizes BAY-induced cell death. Overexperession of SLC7A11 attenuated BAY-inhibited cell viability. The ferroptotic process induced by hHO-1 overexpression further indicated that HO-1 is a key mediator of BAY-induced ferroptosis that operates through cellular redox regulation and iron accumulation. BAY causes compartmentalization of HO-1 into the nucleus and mitochondrion, and followed mitochondrial dysfunctions, leading to lysosome targeting for mitophagy. In this study, we first discovered that BAY induced ferroptosis via Nrf2-SLC7A11-HO-1 pathway and HO-1 is a key mediator by responding to the cellular redox status. Copyright © 2017 Elsevier B.V. All rights reserved.

Incident wave run-up into narrow sloping bays and estuaries

Science.gov (United States)

Sinan Özeren, M.; Postacioglu, Nazmi; Canlı, Umut

2015-04-01

The problem is investigated using Carrier Greenspan hodograph transformations.We perform a quasi-one-dimensional solution well into the bay, far enough of the mouth of the bay. The linearized boundary conditions at the mouth of the bay lead to an integral equation for 2-D geometry. A semi analytical optimization method has been developed to solve this integral equation. When the wavelength of the incident wave is much larger than the width of the bay, the conformalmapping of the bay and the semi infinite sea onto upper complex plane provides a solution of the integral equation in closed form. Particular emphasis is placed on the case where the frequency of the incident waves matches the real-part of the natural frequency of the oscillation of the bay. These natural frequencies are complex because of the radiation conditions imposed at the mouth of the bay. It is found that the complex part of these natural frequencies decreases with decreasing width of the bay. Thus the trapping of the waves in narrower bays leads to a strong resonance phenomenon when the frequency of the incident wave is equal to the real part of the natural frequency.

Elemental analysis of Uranouchi bay seabed sludge using PIXE

International Nuclear Information System (INIS)

Kabir, M. Hasnat; Narusawa, Tadashi; Nishiyama, Fumitaka; Sumi, Katsuhiro

2006-01-01

Elemental analyses were carried out for the seabed sludge collected from Uranouchi bay (Kochi, Japan) using Particle Induced X-ray Emission (PIXE). Seabed-sludge contamination with heavy metals as well as toxic elements becomes one of the most serious environmental problems. The aim of the present study is to investigate the polluted areas in the bay by heavy and toxic elements. As a results of analyses of samples collected from eleven different places in the bay, seventeen elements including toxic ones were detected. The results suggest that the center region of the bay is seriously contaminated by heavy and toxic elements in comparison with the other areas in the bay. (author)

Seismic-Reflection Technology Defines Potential Vertical Bypass in Hydrogeologic Confinement within Tertiary Carbonates of the Southeastern Florida Platform

Science.gov (United States)

Cunningham, K. J.; Walker, C.; Westcott, R. L.

2011-12-01

Continuous improvements in shallow-focused, high-resolution, marine seismic-reflection technology has provided the opportunity to evaluate geologic structures that breach confining units of the Floridan aquifer system within the southeastern Florida Platform. The Floridan aquifer system is comprised mostly of Tertiary platform carbonates. In southeastern Florida, hydrogeologic confinement is important to sustainable use of the Floridan aquifer system, where the saline lower part is used for injection of wastewater and the brackish upper part is an alternative source of drinking water. Between 2007 and 2011, approximately 275 km of 24- and 48-channel seismic-reflection profiles were acquired in canals of peninsular southeastern Florida, Biscayne Bay, present-day Florida shelf margin, and the deeply submerged Miami Terrace. Vertical to steeply dipping offsets in seismic reflections indicate faults, which range from Eocene to possible early Pliocene age. Most faults are associated with karst collapse structures; however, a few tectonic faults of early Miocene to early Pliocene age are present. The faults may serve as a pathway for vertical groundwater flow across relatively low-permeability carbonate strata that separate zones of regionally extensive high-permeability in the Floridan aquifer system. The faults may collectively produce a regional confinement bypass system. In early 2011, twenty seismic-reflection profiles were acquired near the Key Biscayne submarine sinkhole located on the seafloor of the Miami Terrace. Here the water depth is about 365 m. A steeply dipping (eastward) zone of mostly deteriorated quality of seismic-reflection data underlies the sinkhole. Correlation of coherent seismic reflections within and adjacent to the disturbed zone indicates a series of faults occur within the zone. It is hypothesized that upward movement of groundwater within the zone contributed to development of a hypogenic karst system and the resultant overlying sinkhole

Early Holocene estuary development of the Hesselø Bay area, southern Kattegat, Denmark and its implication for Ancylus Lake drainage

Science.gov (United States)

Bendixen, Carina; Boldreel, Lars Ole; Jensen, Jørn Bo; Bennike, Ole; Hübscher, Christian; Clausen, Ole Rønø

2017-12-01

High-resolution shallow seismic data, sediment core information, radiocarbon dating and sequence stratigraphy have been used to interpret the late glacial to early Holocene geological evolution of Hesselø Bay in the southern Kattegat, Denmark. A reconstruction of the early Holocene coastal environment and a description of coastal processes associated with a river outlet into the bay are presented. Weichselian glacial deposits form the lowermost interpreted unit, covered by late glacial (LG) and postglacial (PG, Holocene) sediments. A funnel-shaped estuary existed at the mouth of channels in the period 10.3-9.2 cal. ka BP; the channels drained water from south to north. The early PG is characterised by estuarine and coastal deposits. The early Holocene bars that developed in the estuary are preserved as morphological features on the present-day seabed, possibly as a result of rapid relative sea-level rise. The estuary existed simultaneously with the occurrence and drainage of the Ancylus Lake. The drainage of this lake occurred through the Dana River (palaeo-Great Belt channel) into the southern Kattegat and then into the study area. The level of the Ancylus Lake in the Baltic Sea region dropped significantly at about 10.2 cal. ka BP at the same time as the estuary developed in the Kattegat region. One outcome of the present study is an enhanced understanding of the Ancylus Lake drainage path. No evidence of major erosion is seen, which indicates non-catastrophic continuous water flow from the south without major drainage events of the Ancylus Lake to the southern Kattegat. During the Littorina transgression, coastal estuarine conditions characterized the Hesselø Bay area where elongated ridges formed a bar system. As the Littorina transgression continued, back-stepping of the bar system and coastline occurred. When the transgression breached the Great Belt threshold, flooding caused major erosion throughout the study area.

Climatic and anthropogenic factors changing spawning pattern and production zone of Hilsa fishery in the Bay of Bengal

OpenAIRE

M. Shohidullah Miah

2015-01-01

Hilsa (Tenualosa ilisha Hamilton) as a single species accounts 12% for more than half of the total marine catches. About 2% of the entire population of the country is directly or indirectly engaged with Hilsa fishing. Hilsa has a wide geographical distribution in Asia from the Persian Gulf to the South China Sea. Particularly large stocks are found in Upper Bay of Bengal (BoB) region sustained by the large river systems. The global Hilsa catch is reported 75% from Bangladesh water, 15% from M...

Otolith chemical composition as a useful tool for sciaenid stock discrimination in the south-western Atlantic

Directory of Open Access Journals (Sweden)

Alejandra V. Volpedo

2006-06-01

Full Text Available Striped weakfish (Cynoscion guatucupa and whitemouth croaker (Micropogonias furnieri are important commercial and recreational species found in abundance along the South American Atlantic coast. In recent years otolith chemical composition has been used as a tool for identifying fish stocks for several species. The chemical composition of C. guatucupa and M. furnieri otoliths was determined by inductively coupled plasma-optical emission spectrometry (ICP-OES in samples from coastal sites (Partido de La Costa, Mar del Plata and San Blás Bay. Significant differences in the ratios of Mg/Ca, Mn/Ca and Sr/Ca for C. guatucupa otoliths and Cd/Ca, Cu/Ca, Mg/Ca, Sr/Ca and Zn/Ca for M. furnieri otoliths suggest the existence of two different fish stocks, one originating in the north (including Samborombón Bay and Partido de La Costa fisheries and another originating in the south (including “El Rincón” and San Blás fisheries. These results agree with previous studies on the same species using different methodologies. These stocks may be separated by an oceanographic barrier, the “Frente El Rincón”. Otolith chemical composition has not been previously used in South America for identifying fish stocks and may be a simple, quick and useful tool for the sustainable exploitation and management of commercial species.

The geology of the Collins Bay uranium deposit, Saskatchewan

International Nuclear Information System (INIS)

Jones, B.E.

1980-01-01

The Collins Bay deposit lies within the Churchill Province on the western edge of the Wollaston lithostructural domain where it underlies the eastern edge of the Helikian Athabasca Formation. It is 6 miles north-northeast of the Rabbit Lake mine. Two principal zones of uranium mineralization are described. The A zone, a partly eroded, high-grade pod of metal oxide and arsenides sheathed by clay-like minerals, which trends north-northeast and lies under 25 to 40 feet of water; and the B zone, which lies 6 000 ft south of the A, subcrops under till cover and is a partly eroded zone composed of metal oxide and arsenides which occur within variably altered Athabasca Formation. The deposit is typical of the unconformity-type uranium-nickel deposits of the Athabasca Basin. Observed features fit well with the diagenetic-hydrothermal model for such deposts. (auth)

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

Humboldt Bay, California Benthic Habitats 2009 Geoform

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

Humboldt Bay, California Benthic Habitats 2009 Substrate

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

Humboldt Bay Benthic Habitats 2009 Aquatic Setting

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

Humboldt Bay, California Benthic Habitats 2009 Geodatabase

Data.gov (United States)

National Oceanic and Atmospheric Administration, Department of Commerce — Humboldt Bay is the largest estuary in California north of San Francisco Bay and represents a significant resource for the north coast region. Beginning in 2007 the...

Contaminant transport in Massachusetts Bay

Science.gov (United States)

Butman, Bradford

Construction of a new treatment plant and outfall to clean up Boston Harbor is currently one of the world's largest public works projects, costing about $4 billion. There is concern about the long-term impact of contaminants on Massachusetts Bay and adjacent Gulf of Maine because these areas are used extensively for transportation, recreation, fishing, and tourism, as well as waste disposal. Public concern also focuses on Stellwagen Bank, located on the eastern side of Massachusetts Bay, which is an important habitat for endangered whales. Contaminants reach Massachusetts Bay not only from Boston Harbor, but from other coastal communities on the Gulf of Maine, as well as from the atmosphere. Knowledge of the pathways, mechanisms, and rates at which pollutants are transported throughout these coastal environments is needed to address a wide range of management questions.

Bayes linear statistics, theory & methods

CERN Document Server

Goldstein, Michael

2007-01-01

Bayesian methods combine information available from data with any prior information available from expert knowledge. The Bayes linear approach follows this path, offering a quantitative structure for expressing beliefs, and systematic methods for adjusting these beliefs, given observational data. The methodology differs from the full Bayesian methodology in that it establishes simpler approaches to belief specification and analysis based around expectation judgements. Bayes Linear Statistics presents an authoritative account of this approach, explaining the foundations, theory, methodology, and practicalities of this important field. The text provides a thorough coverage of Bayes linear analysis, from the development of the basic language to the collection of algebraic results needed for efficient implementation, with detailed practical examples. The book covers:The importance of partial prior specifications for complex problems where it is difficult to supply a meaningful full prior probability specification...

78 FR 54585 - Safety Zone; Escape to Miami Triathlon, Biscayne Bay, Miami, FL

Science.gov (United States)

2013-09-05

... Act (APA) (5 U.S.C. 553(b)). This provision authorizes an agency to issue a rule without prior notice... Security Management Directive 023-01 and Commandant Instruction M16475.lD, which guide the Coast Guard in...

76 FR 24837 - Regulated Navigation Area; Columbus Day Weekend, Biscayne Bay, Miami, FL

Science.gov (United States)

2011-05-03

.... Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535-8724, e-mail Paul.A.Steiner... questions concerning its provisions or options for compliance, please contact Lieutenant Paul A. Steiner, Sector Miami Prevention Department, Coast Guard; telephone 305-535- 8724, e-mail Paul.A.Steiner@uscg.mil...

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.

Mex Bay

African Journals Online (AJOL)

user

2015-02-23

Feb 23, 2015 ... surveys to assess the vulnerability of the most important physical and eutrophication parameters along. El- Mex Bay coast. As a result of increasing population and industrial development, poorly untreated industrial waste, domestic sewage, shipping industry and agricultural runoff are being released to the.

Occurrence of marine algal toxins in oyster and phytoplankton samples in Daya Bay, South China Sea.

Science.gov (United States)

Jiang, Tao; Liu, Lei; Li, Yang; Zhang, Jing; Tan, Zhijun; Wu, Haiyan; Jiang, Tianjiu; Lu, Songhui

2017-09-01

The occurrence and seasonal variations of marine algal toxins in phytoplankton and oyster samples in Daya Bay (DYB), South China Sea were investigated. Two Dinophysis species, namely, D. caudata and D. acuminata complex, were identified as Okadaic acid (OA)/pectenotoxin (PTX) related species. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) analysis demonstrated that 2.04-14.47 pg PTX2 per cell was the predominant toxin in single-cell isolates of D. caudata. D. acuminata was not subjected to toxin analysis. The occurrence of OAs in phytoplankton concentrates of net-haul sample coincided with the presence of D. accuminata complex, suggesting that this species is most likely an OA producer in this sea area. OA, dinophysistoxins-1 (DTX1), PTX2, PTX2sa, gymnodimine (GYM), homoyessotoxin (homoYTX), and domoic acid (DA) demonstrated positive results in net haul samples. To our best knowledge, this paper is the first to report the detection of GYM, DA, and homoYTX in phytoplankton samples in Chinese coastal waters. Among the algal toxins, GYM demonstrated the highest frequency of positive detections in phytoplankton concentrates (13/17). Five compounds of algal toxins, including OA, DTX1, PTX2, PTX2sa, and GYM, were detected in oyster samples. DA and homoYTX were not detected in oysters despite of positive detections for both in the phytoplankton concentrates. However, neither the presence nor absence of DA in oysters can be determined because extraction conditions with 100% methanol used to isolate toxins from oysters (recommended by the EU-Harmonised Standard Operating Procedure, 2015) would likely be unsuitable for this water-soluble toxin. In addition, transformation of DA during the digestion process of oysters may also be involved in the negative detections of this toxin. GYM exhibited the highest frequency of positive results in oysters (14/17). OAs were only detected in the hydrolyzed oyster samples. The detection rates of PTX and PTX2sa in

San Francisco 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.,

Early Silurian (Llandoverian) Leask Point and Charlton Bay bioherms, Manitoulin Island, Ontario, Canada

Energy Technology Data Exchange (ETDEWEB)

Mielczarek, W.; Copper, P.

1986-08-01

About 300 bioherms are known in the Llandoverian Manitoulin Formation of eastern Manitoulin Island. In the South Bay area, the large Leask Piont bioherm and Charlton Bay patch-reef complex lack a distinct skeletal growth framework. Bioherms consist of mudstone and wackestone, with isolated lenses of bafflestone, boundstone, floatstone. Fossils are scarce, but crinozoans and bryozoans comprise about 90% of the bioclasts. Other fauna include stromatoporoids, corals, brachiopods, gastropods, trilobites, and probable algae (algae are difficult to identify and may have played a significant role). Faunal ratios remained relatively constant during mound growth. Soft substrates with sedimentation rates of a few millimeters per year are suggested by bedding type and morphologic dominance of lamellar and tabular corals and stromatoporoids. An increased sedimentation rate, resulting from shoaling, is indicated by more overturned, broadly conical corals in the upper parts of the mounds. Shoaling may be responsible for cessation of mound growth. Lithoclasts are more common in the upper parts of the mounds. They formed when semiconsolidated muds were disturbed and redeposited during storms. Megarippled interreef surface areas, largely devoid of coral growth, indicate mud instability at Charlton Bay. Lack of suitable stable substrates may have hampered coral development. Dolomitization was postdepositional. The diagenetic sequence occurred in three stages: 1)selective pyritization and silicification, formation of an early muddy dolomite replacing the mud fraction of the dolostone, lithification and formation of rare calcite cement and neomorphic syntaxial rims; 2)clear, coarse dolomite replacing pore-filling calcite cement, syntaxial rims, and unaltered macrofossils, stylolitization, grain-to-grain dissolution; and 3)a late dolomite found mainly as fine rhombs in stylolites, solution seams, and intraskeletal pore space.

PEMANFATAN TEOREMA BAYES DALAM PENENTUAN PENYAKIT THT

Directory of Open Access Journals (Sweden)

Sri Winiarti

2008-07-01

Full Text Available Dalam konsep pelacakan dalam mencari solusi dengan pendekatan artificial inteligent, ada berbagai metode yang dapat diterapkan untuk mengatasi masalah ketidakpastian saat proses pelacakan terjadi. Salah satunya adalah teorema bayes. Adanya ketidakpastian pada proses pelacakan dapat terjadi karena adanya perubahan pengetahuan yang ada di dalam sistem. Untuk itu diperlukan adanya suatu metode untuk mengatasi permasalahan tersebut. Dalam penelitian ini telah diterapkan suatu metode untuk mengatasi ketidakpastian dengan teorema Bayes pada kasus pelacakan untuk mendiagnosa penyakit pada THT (Telinga,Hidung dan Tenggorokan. Subjek pada penelitian ini adalah proses pelacakan untuk menentukan penyakit THT dengan model penalaran forward chaining dan metode kepastiannya menggunakan teorema bayes dengan cara menghitung nilai probabilitas suatu penyakit dan membandingkan probabilitas setiap gejalanya. Model pengembangan perangkat lunak yang digunakan dalam penelitian ini adalah Waterfall. Metode Waterfall diawali dengan analisis data, perancangan sistem, pengkodean menggunakan Visual Basic 6.0, pengujian sistem dengan black box test dan alfa test. Dari penelitian yang dilakukan menghasilkan sebuah perangkat lunak yaitu yang mampu menentukan penyakit pada THT dengan menerapkan metode bayes untuk mengatasi ketidakpastian. Hasil uji coba sistem menujukkan bahwa aplikasi ini layak dan dapat digunakan. Kata kunci : Penyakit, THT, Teorema Bayes.

Geochemistry of sediments in the Back Bay and Yellowknife Bay of the Great Slave Lake

International Nuclear Information System (INIS)

Mudroch, A.; Joshi, S.R.; Sutherland, D.; Mudroch, P.; Dickson, K.M.

1989-01-01

Gold mining activities have generated wastes with high concentrations of arsenic and zinc in the vicinity of Yellowknife, Northwest Territories, Canada. Some of the waste material has been discharged into Yellowknife Bay of Great Slave Lake. Concentrations of arsenic and zinc were determined in sediment cores collected at the depositional areas of Yellowknife Bay. Sedimentation rates were estimated using two different radiometric approaches: the depth profiles of cesium 137 and lead 210. Geochemical analysis of the sediment cores indicated input of similar material into sampling areas over the past 50 yr. Age profiles of the sediment constructed from the radionuclide measurements were used to determine historical trends of arsenic and zinc inputs into Yellowknife Bay. The historical record was in good agreement with implemented remedial actions and the usage patterns of both elements. 16 refs., 6 figs., 3 tabs

Helicopter electromagnetic survey of the Model Land Area, Southeastern Miami-Dade County, Florida

Science.gov (United States)

Fitterman, David V.; Deszcz-Pan, Maria; Prinos, Scott T.

2012-01-01

This report describes a helicopter electromagnetic survey flown over the Model Land Area in southeastern Miami-Dade County, Florida, to map saltwater intrusion in the Biscayne aquifer. The survey, which is located south and east of Florida City, Florida, covers an area of 115 square kilometers with a flight-line spacing of 400 meters. A five-frequency, horizontal, coplanar bird with frequencies ranging from 400 to 100,000 Hertz was used. The data were interpreted using differential resistivity analysis and inversion to produce cross sections and resistivity depth-slice maps. The depth of investigation is as deep as 100 meters in freshwater-saturated portions of the Biscayne aquifer and the depth diminishes to about 50 meters in areas that are intruded by saltwater. The results compare favorably with ground-based, time-domain electromagnetic soundings and induction logs from observation wells in the area. The base of a high-resistivity, freshwater-saturated zone mapped in the northern 2 kilometers of the survey area corresponds quite well with the base of the surficial aquifer that has been determined by drilling. In general, saltwater in the survey area extends 9 to 12 kilometers inland from the coast; however, there is a long nose of saltwater centered along the Card Sound Road Canal that extends 15 kilometers inland. The cause of this preferential intrusion is likely due to uncontrolled surface flow along the canal and subsequent leakage of saltwater into the aquifer. Saltwater also extends farther inland in the area between U.S. Highway 1 and Card Sound Road than it does to the west of this area. Until 1944, a railroad grade occupied the current location of U.S. Highway 1. Borrow ditches associated with the railroad grade connected to Barnes Sound and allowed saltwater to flow during droughts and storm surges to within a few kilometers of Florida City. Relicts of this saltwater that settled to the bottom of the Biscayne aquifer can be seen in the helicopter

Optimasi Naive Bayes Dengan Pemilihan Fitur Dan Pembobotan Gain Ratio

Directory of Open Access Journals (Sweden)

I Guna Adi Socrates

2016-03-01

Full Text Available Naïve Bayes merupakan salah satu metode data mining yang umum digunakan dalam klasifikasi dokumen berbasis text. Kelebihan dari metode ini adalah algoritma yang sederhana dengan  kompleksitas  perhitungan  yang  rendah.  Akan  tetapi,  pada  metode  Naïve  Bayes terdapat kelemahan dimana sifat independensi dari fitur Naïve Bayes tidak dapat selalu diterapkan sehingga akan berpengaruh pada tingkat akurasi perhitungan. Maka dari itu, metode Naïve Bayes perlu dioptimasi dengan cara pemberian bobot mengunakan Gain Ratio. Namun, pemberian bobot pada Naïve Bayes menimbulkan permasalahan pada penghitungan probabilitas setiap    dokumen, dimana fitur  yang tidak  merepresentasikan kelas  yang diuji banyak muncul sehingga terjadi kesalahan klasifikasi. Oleh karena itu, pembobotan Naïve Bayes   masih   belum   optimal.   Paper   ini mengusulkan  optimasi  metode   Naïve   Bayes mengunakan pembobotan Gain Ratio yang ditambahkan dengan metode pemilihan fitur pada kasus klasifikasi teks. Hasil penelitian ini menunjukkan bahwa optimasi metode Naïve Bayes menggunakan pemilihan fitur dan pembobotan menghasilkan akurasi sebesar 94%.

Science to support the understanding of south Texas surface-water and groundwater resources in a changing landscape

Science.gov (United States)

Ockerman, Darwin J.; Garcia, Travis J.; Opsahl, Stephen P.

2012-01-01

Against a backdrop of constant cycles of extreme hydrologic conditions ranging from oppressive droughts to life-threatening floods, the water-resource landscape of south Texas is undergoing constant change. Demands on water resources are increasing because of changes related to population growth, energy demands, agricultural practices, and other human-related activities. In south Texas, the Nueces, San Antonio, and Guadalupe River Basins cover approximately 50,000 square miles and include all or part of 45 counties. These stream systems transect the faulted and fractured carbonate rocks of the Edwards aquifer recharge zone and provide the largest sources of recharge to the aquifer. As the streams make their way to the Gulf of Mexico, they provide water for communities and ecosystems in south Texas and deliver water, sediment, and nutrients to the south Texas bays and estuaries.

Recent results from Daya Bay

Directory of Open Access Journals (Sweden)

Chua Ming-chung

2016-01-01

Full Text Available Utilizing powerful nuclear reactors as antineutrino sources, high mountains to provide ample shielding from cosmic rays in the vicinity, and functionally identical detectors with large target volume for near-far relative measurement, the Daya Bay Reactor Neutrino Experiment has achieved unprecedented precision in measuring the neutrino mixing angle θ13 and the neutrino mass squared difference |Δm2ee|. I will report the latest Daya Bay results on neutrino oscillations and light sterile neutrino search.

Assessment of relationship between rainfall and Escherichia coli in clams (Chamelea gallina using the Bayes Factor

Directory of Open Access Journals (Sweden)

Cesare Ciccarelli

2017-08-01

Full Text Available Consumption of bivalve shellfish harvested from water contaminated with sewage pollution presents a risk of human infections and targeting control measures require a good understanding of environmental factors influencing the transport and the fate of faecal contaminants within the hydrological catchments. Although there has been extensive development of regression models, the point of this paper, focused on the relationship between rainfall events and concentrations of Escherichia coli monitored in clams, was the use of a Bayesian approach, by the Bayes Factor. The study was conducted on clams harvested from the south coast of Marche Region (Italy, a coastal area impacted by continuous treated effluents, intermittent rainfalldependent untreated sewage spillage - as a consequence of stormwater overflowing - and rivers with an ephemeral flow regime. The work compared the different interpretation criteria of Bayes Factor, confirmed that E. coli concentrations in clams from the studied area varied in correlation with rainfall events, and demonstrated the effectiveness of Bayes Factor in the assessment of shellfish quality in coastal marine waters. However, it suggested that further investigations would be warranted to determine which environmental factors provide the better basis for accurate and timely predictions. Furthermore the gathered data could be useful, to the local authorities of Marche Region, in the definition of flexible monitoring programmes, taking into account the atmospheric events that could affect the correct functioning of sewage managing systems and the flow of tributary rivers.

77 FR 30443 - Safety Zone; Alexandria Bay Chamber of Commerce, St. Lawrence River, Alexandria Bay, NY

Science.gov (United States)

2012-05-23

...The Coast Guard proposes to establish a temporary safety zone on the St. Lawrence River, Alexandria Bay, NY. This proposed rule is intended to restrict vessels from a portion of the St. Lawrence River during the Alexandria Bay Chamber of Commerce fireworks display. The safety zone established by this proposed rule is necessary to protect spectators and vessels from the hazards associated with a fireworks display.

Holocene evolution of Apalachicola Bay, Florida

Science.gov (United States)

Osterman, L.E.; Twichell, D.C.; Poore, R.Z.

2009-01-01

A program of geophysical mapping and vibracoring was conducted to better understand the geologic evolution of Apalachicola Bay. Analyses of the geophysical data and sediment cores along with age control provided by 34 AMS 14C dates on marine shells and wood reveal the following history. As sea level rose in the early Holocene, fluvial deposits filled the Apalachicola River paleochannel, which extended southward under the central part of the bay and seaward across the continental shelf. Sediments to either side of the paleochannel contain abundant wood fragments, with dates documenting that those areas were forested at 8,000 14C years b.p. As sea level continued to rise, spits formed of headland prodelta deposits. Between ???6,400 and ???2,500 14C years b.p., an Apalachicola prodelta prograded and receded several times across the inner shelf that underlies the western part of the bay. An eastern deltaic lobe was active for a shorter time, between ???5,800 and 5,100 14C years b.p. Estuarine benthic foraminiferal assemblages occurred in the western bay as early as 6,400 14C years b.p., and indicate that there was some physical barrier to open-ocean circulation and shelf species established by that time. It is considered that shoals formed in the region of the present barrier islands as the rising sea flooded an interstream divide. Estuarine conditions were established very early in the post-glacial flooding of the bay. ?? 2009 US Government.

Long-term morphologic evolution of the Hangzhou Bay, China

Science.gov (United States)

Wen, W.; Zhijun, D.; Hualiang, X.

2013-12-01

Estuaries are the most productive ecosystems of coastal zones in the world, which are significant to mankind as places of navigation, recreation and commerce as well as extensive and diverse habitats for wildlife. However, most estuary environments in the world had occurred greatly changes in recent decades. These estuaries have suffered from impacts of forcing factors including wave climate, mean sea level change and storm surge, especial to the intensive human activities such as training wall construction, channel dredging, sand mining and dam constructions. Thus, there have been increasing concerns about estuary environment changes under effects of different factors. Riverine loads into the Changjiang Estuary have declined dramatically with the construction of Three Gorges Dam (TGD) in 2003. The morphological evolution of the Hangzhou bay that located the southern proximity of the Yangtze estuary starts to attract increasing attentions due to most material of the Hangzhou bay received from Yangtze estuary. In this paper, historical bathymetric charts were digitized and analyzed within a GIS to provide quantitative estimate of changes in volumes in different regions below 0 m elevation. The results show that Hangzhou bay has experienced a major loss in estuarine volume of about 15% with annual mean sediment deposition rate of 80 million m3/a during the last 75 years. However, there is a large-scale spatial adjustment in Hangzhou bay: Bathymetric changes of the Hangzhou bay can be rapidly shifted within the range of 8-10 classes. Volume of the Jinshanzui upstream of the Hangzhou bay has obviously decreased in the last 75 years, especially during 2003-2008. However, Volume of the southern Hangzhou bay has experienced slowly decrease with minor deposition. The northern Hangzhou bay had largely volume changes with rapidly decrease during 1931-1981, and drastically increase since 2003. Further analysis of the bathymetric data relating to possible factors indicates

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

Parameter Identification by Bayes Decision and Neural Networks

DEFF Research Database (Denmark)

Kulczycki, P.; Schiøler, Henrik

1994-01-01

The problem of parameter identification by Bayes point estimation using neural networks is investigated.......The problem of parameter identification by Bayes point estimation using neural networks is investigated....

Chesapeake Bay baseline data acquisition, toxics in the Chesapeake Bay. Final preliminary report, 1946-78

International Nuclear Information System (INIS)

1978-07-01

This report identifies researchers, research activities, and data files applicable to the Chesapeake Bay estuarine system. The identified data were generated after 1973 on the following: submerged aquatic vegetation, shellfish bed closures, eutrophication, toxics accumulation in the food chain, dredging and spoil disposal, hydrologic modifications, modification of fisheries, shoreline erosion, wetlands alterations, and the effects of boating and shipping on water quality. Major past and current program monitoring in the Bay and its tributaries are summarized according to frequency

Wind-Driven Waves in Tampa Bay, Florida

Science.gov (United States)

Gilbert, S. A.; Meyers, S. D.; Luther, M. E.

2002-12-01

Turbidity and nutrient flux due to sediment resuspension by waves and currents are important factors controlling water quality in Tampa Bay. During December 2001 and January 2002, four Sea Bird Electronics SeaGauge wave and tide recorders were deployed in Tampa Bay in each major bay segment. Since May 2002, a SeaGauge has been continuously deployed at a site in middle Tampa Bay as a component of the Bay Regional Atmospheric Chemistry Experiment (BRACE). Initial results for the summer 2002 data indicate that significant wave height is linearly dependent on wind speed and direction over a range of 1 to 12 m/s. The data were divided into four groups according to wind direction. Wave height dependence on wind speed was examined for each group. Both northeasterly and southwesterly winds force significant wave heights that are about 30% larger than those for northwesterly and southeasterly winds. This difference is explained by variations in fetch due to basin shape. Comparisons are made between these observations and the results of a SWAN-based model of Tampa Bay. The SWAN wave model is coupled to a three-dimensional circulation model and computes wave spectra at each model grid cell under observed wind conditions and modeled water velocity. When SWAN is run without dissipation, the model results are generally similar in wave period but about 25%-50% higher in significant wave height than the observations. The impact of various dissipation mechanisms such as bottom drag and whitecapping on the wave state is being investigated. Preliminary analyses on winter data give similar results.

Characterizing the parent and alkyl polycyclic aromatic hydrocarbons in the Pearl River Estuary, Daya Bay and northern South China Sea: Influence of riverine input

International Nuclear Information System (INIS)

Yuan, Ke; Wang, Xiaowei; Lin, Li; Zou, Shichun; Li, Yan; Yang, Qingshu; Luan, Tiangang

2015-01-01

Distributions of 31 parent polycyclic aromatic hydrocarbons (PAHs) and 29 alkyl PAHs in surface sediments of the Pearl River Estuary (PRE), Daya Bay (DYB) and northern South China Sea (SCS) were examined to study the influence of riverine input. It was found that the contributions of riverine input to sediment PAHs in PRE was much higher than other areas. However, higher proportion of alkyl PAHs and low molecular weight PAHs in DYB and the northern SCS was observed, indicating their different sources. Nevertheless, the sediment PAHs in PRE were heterogeneous and affected by the hydrodynamic conditions. The high molecular weight PAHs were dominant in PRE and enriched in the depositional area of suspended particular matter (SPM). Moreover, the concentration of PAHs in SPM was similar to those in surface sediments and dominated in water columns. Therefore, SPM played a very important role in transportation and distribution of PAHs in PRE. - Highlights: • EPA 16 PAHs contributed a small amount of total PAHs. • Alkyl PAHs showed different behaviors from parent PAHs. • High weight PAHs preferably indicated riverine input. • PAHs distribution in sediment was related with the suspended particle deposition. - Suspended particular matter played a very important role in distribution of PAHs in tide-dominated estuary and alkyl PAHs showed different behavior from parent PAHs

Macroalgal diversity along an inshore-offshore environmental gradient in the Jakarta Bay - Thousand Islands reef complex, Indonesia

Science.gov (United States)

Draisma, Stefano G. A.; Prud'homme van Reine, Willem F.; Herandarudewi, Sekar M. C.; Hoeksema, Bert W.

2018-01-01

The Jakarta Bay - Thousand Islands reef complex extends to more than 80 km in northwest direction from the major conurbation Jakarta (Indonesia) along a pronounced inshore to offshore environmental gradient. The present study aims to determine to what extent environmental factors can explain the composition of macroalgal communities on the reefs off Jakarta. Therefore, the presence-absence of 67 macroalgal taxa was recorded for 27 sampling sites along the inshore-offshore disturbance gradient and analysed with substrate variables and water quality variables. The macroalgal richness pattern matches the pattern of other reef taxa. The 27 sites could be assigned to one of four geographical zones with 85% certainty based on their macroalgal taxon assemblages. These four zones (i.e., Jakarta Bay and, respectively, South, Central, and North Thousand Islands) had significantly different macroalgal assemblages, except for the North and South zones. Along the nearshore gradient there was a greater shift in taxon composition than within the central Thousand Islands. The patterns of ten habitat and water quality variables resembled the macroalgal diversity patterns by 56%. All ten variables together explained 69% of the variation in macroalgal composition. Shelf depth, % sand cover, gelbstoff/detrital material, chlorophyll a concentration, seawater surface temperature, and % dead coral cover were the best predictors of seaweed flora composition. Furthermore, 44 macroalgal species represented new records for the area. The present study provides important baseline data of macroalgae in the area for comparison in future biodiversity assessments in the area and elsewhere in the region.

Seasonal and Intraseasonal Variability of Mesoscale Convective Systems over the South Asian Monsoon Region

Energy Technology Data Exchange (ETDEWEB)

Virts, Katrina S.; Houze, Robert A.

2016-12-01

Seasonal and intraseasonal differences in mesoscale convective systems (MCSs) over South Asia are examined using A-Train satellites, a ground-based lightning network, and reanalysis fields. Pre-monsoon (April-May) MCSs occur primarily over Bangladesh and the eastern Bay of Bengal. During the monsoon (June-September), small MCSs occur over the Meghalaya Plateau and northeast Himalayan notch, while large and connected MCSs are most widespread over the Bay of Bengal. Monsoon MCSs produce less lightning and exhibit more extensive stratiform and anvil reflectivity structures in CloudSat observations than do pre-monsoon MCSs. During the monsoon season, Bay of Bengal and Meghalaya Plateau MCSs vary with the 30-60 day northward-propagating intraseasonal oscillation, while northeast Himalayan notch MCSs are associated with weak large-scale anomalies but locally enhanced CAPE. During intraseasonal active periods, a zone of enhanced large and connected MCSs, precipitation, and lightning extends from the northeastern Arabian Sea southeast over India and the Bay of Bengal, flanked by suppressed anomalies. Spatial variability is observed within this enhancement zone: lightning is most enhanced where MCSs are less enhanced, and vice versa. Reanalysis composites indicate that Bay of Bengal MCSs are associated with monsoon depressions, which are frequent during active monsoon periods, while Meghalaya Plateau MCSs are most frequent at the end of break periods, as anomalous southwesterly winds strengthen moist advection toward the terrain. Over both regions, MCSs exhibit more extensive stratiform and anvil regions and less lightning when the large-scale environment is moister, and vice versa.

Phytoplankton growth, dissipation, and succession in estuarine environments. [Chesapeake Bay

Energy Technology Data Exchange (ETDEWEB)

Seliger, H H

1976-01-01

Two major advances in a study of phytoplankton ecology in the Chesapeake Bay are reported. The annual subsurface transport of a dinoflagellate species (Prorocentrum mariae labouriae) from the mouth of the bay a distance northward of 120 nautical miles to the region of the Bay Bridge was followed. Prorocentrum is a major seasonal dinoflagellate in the Chespeake Bay and annually has been reported to form mahogany tides, dense reddish-brown patches, in the northern bay beginning in late spring and continuing through the summer. Subsequent to this annual appearance the Prorocentrum spread southward and into the western tributary estuaries. The physiological behavioral characteristics of the Prorocentrum were correlated with the physical water movements in the bay. A phytoplankton cage technique for the measurement in situ of the growth rates of natural mixed populations is described. (CH)

Mobile Bay turbidity study

Science.gov (United States)

Crozier, G. F.; Schroeder, W. W.

1978-01-01

The termination of studies carried on for almost three years in the Mobile Bay area and adjacent continental shelf are reported. The initial results concentrating on the shelf and lower bay were presented in the interim report. The continued scope of work was designed to attempt a refinement of the mathematical model, assess the effectiveness of optical measurement of suspended particulate material and disseminate the acquired information. The optical characteristics of particulate solutions are affected by density gradients within the medium, density of the suspended particles, particle size, particle shape, particle quality, albedo, and the angle of refracted light. Several of these are discussed in detail.

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...

With Prudhoe Bay in decline

International Nuclear Information System (INIS)

Davis, J.M.; Pollock, J.R.

1992-01-01

Almost every day, it seems, someone is mentioning Prudhoe Bay---its development activities, the direction of its oil production, and more recently its decline rate. Almost as frequently, someone is mentioning the number of companies abandoning exploration in Alaska. The state faces a double-edged dilemma: decline of its most important oil field and a diminished effort to find a replacement for the lost production. ARCO has seen the Prudhoe Bay decline coming for some time and has been planning for it. We have reduced staff, and ARCO and BP Exploration are finding cost-effective ways to work more closely together through such vehicles as shared services. At the same time, ARCO is continuing its high level of Alaskan exploration. This article will assess the future of Prudhoe Bay from a technical perspective, review ARCO's exploration plans for Alaska, and suggest what the state can do to encourage other companies to invest in this crucial producing region and exploratory frontier

Bayes Empirical Bayes Inference of Amino Acid Sites Under Positive Selection

DEFF Research Database (Denmark)

Yang, Ziheng; Wong, Wendy Shuk Wan; Nielsen, Rasmus

2005-01-01

, with > 1 indicating positive selection. Statistical distributions are used to model the variation in among sites, allowing a subset of sites to have > 1 while the rest of the sequence may be under purifying selection with ... probabilities that a site comes from the site class with > 1. Current implementations, however, use the naive EB (NEB) approach and fail to account for sampling errors in maximum likelihood estimates of model parameters, such as the proportions and ratios for the site classes. In small data sets lacking...... information, this approach may lead to unreliable posterior probability calculations. In this paper, we develop a Bayes empirical Bayes (BEB) approach to the problem, which assigns a prior to the model parameters and integrates over their uncertainties. We compare the new and old methods on real and simulated...

Riverine organic matter composition and fluxes to Hudson Bay

Science.gov (United States)

Kuzyk, Z. Z. A.; Macdonald, R. W.; Goni, M. A.; Godin, P.; Stern, G. A.

2016-12-01

With warming in northern regions, many changes including permafrost degradation, vegetation alteration, and wildfire incidence will impact the carbon cycle. Organic carbon (OC) carried by river runoff to northern oceans has the potential to provide integrated evidence of these impacts. Here, concentrations of dissolved (DOC) and particulate (POC) OC are used to estimate terrestrial OC transport in 17 major rivers draining varied vegetative and permafrost conditions into Hudson Bay and compositional data (lignin and 14C) to infer OC sources. Hudson Bay lies just south of the Arctic Circle in Canada and is surrounded by a large drainage basin (3.9 × 106 km2) dominated by permafrost. Analysis of POC and DOC in the 17 rivers indicates that DOC dominates the total OC load. The southern rivers dominate. The Nelson and Churchill Rivers to the southwest are particularly important suppliers of OC partly because of large drainage basins but also perhaps because of impacts by hydroelectric development, as suggested by a 14C age of DOC in the Churchill River of 2800 years. Higher DOC and POC concentrations in the southern rivers, which have substantive areas only partially covered by permafrost, compared to northern rivers draining areas with complete permafrost cover, implies that warming - and hence permafrost thawing - will lead to progressively higher DOC and POC loads for these rivers. Lignin composition in the organic matter (S/V and C/V ratios) reveals mixed sources of OC consistent with the dominant vegetation in the river basins. This vegetation is organized by latitude with southern regions below the tree line enriched by woody gymnosperm sources (boreal forest) and northern regions enriched with organic matter from non-woody angiosperms (flowering shrubs, tundra). Acid/Aldehyde composition together with Δ14C data for selected DOC samples suggest that most of the lignin has undergone oxidative degradation, particularly the DOC component. However, high Δ14C ages

Benthic harpacticoid copepods of Jiaozhou Bay, Qingdao

Science.gov (United States)

Ma, Lin; Li, Xinzheng

2017-09-01

The species richness of benthic harpacticoid copepod fauna in Jiaozhou Bay, Qingdao, on the southern coast of Shandong Peninsula, has not been comprehensively studied. We present a preliminary inventory of species for this region based on material found in nine sediment samples collected from 2011 to 2012. Our list includes 15 species belonging to 15 genera in 9 families, the most speciose family was the Miraciidae Dana, 1846 (seven species); all other families were represented by single species only. Sediment characteristics and depth are determined to be important environmental determinants of harpacticoid distribution in this region. We briefly detail the known distributions of species and provide a key to facilitate their identification. Both harpacticoid species richness and the species/genus ratio in Jiaozhou Bay are lower than in Bohai Gulf and Gwangyang Bay. The poor knowledge of the distribution of benthic harpacticoids, in addition to low sampling effort in Jiaozhou Bay, likely contribute to low species richness.

Seismic stratigraphic architecture of the Disko Bay trough-mouth fan system, West Greenland

Science.gov (United States)

Hofmann, Julia C.; Knutz, Paul C.

2015-04-01

Spatial and temporal changes of the Greenland Ice Sheet on the continental shelf bordering Baffin Bay remain poorly constrained. Then as now, fast-flowing ice streams and outlet glaciers have played a key role for the mass balance and stability of polar ice sheets. Despite their significance for Greenland Ice Sheet dynamics and evolution, our understanding of their long-term behaviour is limited. The central West Greenland margin is characterized by a broad continental shelf where a series of troughs extend from fjords to the shelf margin, acting as focal points for trough-mouth fan (TMF) accummulations. The sea-ward bulging morphology and abrupt shelf-break of these major depositional systems is generated by prograding depocentres that formed during glacial maxima when ice streams reached the shelf edge, delivering large amounts of subglacial sediment onto the continental slope (Ó Cofaigh et al., 2013). The aim of this study is to unravel the seismic stratigraphic architecture and depositional processes of the Disko Bay TMF, aerially the largest single sedimentary system in West Greenland, using 2D and 3D seismic reflection data, seabed bathymetry and stratigraphic information from exploration well Hellefisk-1. The south-west Disko Bay is intersected by a deep, narrow trough, Egedesminde Dyb, which extends towards the southwest and links to the shallower and broader cross-shelf Disko Trough (maximum water depths of > 1000 m and a trough length of c. 370 km). Another trough-like depression (trough length of c. 120 km) in the northern part of the TMF, indicating a previous position of the ice stream, can be distinguished on the seabed topographic map and the seismic images. The Disko Bay TMF itself extends from the shelf edge down to the abyssal plain (abyssal floor depths of 2000 m) of the southern Baffin Bay. Based on seismic stratigraphic configurations relating to reflection terminations, erosive patterns and seismic facies (Mitchum et al., 1977), the TMF

Concentrations of PAHs (Polycyclicaromatic Hydrocarbons Pollutant in Sediment of The Banten Bay

Directory of Open Access Journals (Sweden)

Khozanah Munawir

2018-02-01

Full Text Available Banten Bay is end of stream for a few rivers from Banten mainland where many manufactures and petrochemical industries are built. This may give environmental pressure of water quality of the bay due to pollutant input, such as Polycyclic Aromatic Hydrocarbons (PAHs. This study is to identify those pollutants and determine their total concentration and distribution in sediments. Surface sediment samples were collected in four zones: inner coastline within the bay, middle bay, coastline off the bay and outer of the Bay in April 2016. PAH components were extracted and measured using a gas chromatography-mass spectrometry. Levels of total PAHs in sediments in inner coastline within the bay ranged between 0.381-2.654 ppm with an average of 1.288 ppm, middle of the bay ranged between 0.747-1.762 ppm with an average of 1.198 ppm, outer of the bay ranged between 0.192-1.394 ppm with an average of 0.921 ppm, and east coast of the bay ranged between 0.191-1.394 ppm and an average of 0.778 ppm. The levels of total PAH contamination is apparently lower than those of PAH threshold in sediments (i.e. 4.5 ppm. Keywords: PAHs (Polycyclic Aromatic Hydrocarbons, Banten Bay

Analysis of water quality and circulation of four recreational Miami beaches through the use of Lagrangian Coherent Structures.

Science.gov (United States)

Fiorentino, L A; Olascoaga, M J; Reniers, A

2014-06-15

Four popular, recreational beaches in Miami, FL are Hobie Beach, Virginia Key Beach, Crandon Park Beach, and Bill Baggs Cape Florida State Park. While all of the beaches are within a few miles of each other in Biscayne Bay, they have greatly differing water qualities, as determined by the testing for fecal indicator bacteria performed by the Florida Department of Health. Using the geodesic theory of transport barriers, we identify Lagrangian Coherent Structures (LCSs) in each area. We show how these material curves, which shape circulation and mixing patterns, can be used to explain the incongruous states of the water at beaches that should be comparable. The LCSs are computed using a hydrodynamic model and verified through field experimentation at each beach. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Fouling assemblages associated with estuarine artificial reefs in new South Wales, Australia

Directory of Open Access Journals (Sweden)

Rob Mckenzie

2011-01-01

Full Text Available Previous studies examining the dynamics of succession on artificial reefs have predominantly focussed on fish communities and largely ignored the role of fouling assemblages in explaining the patterns of community structure associated with artificial reefs. The objective of this study was to record the development of epibiotic assemblages on three "design specific" (Reef Ball® estuarine artificial reefs systems located in Lake Macquarie, Botany Bay and St Georges Basin in New South Wales, Australia. Recruitment to the artificial reefs was relatively rapid with the majority of taxa identified over the two-year study period observed within the first year post-deployment. The artificial reefs in Lake Macquarie and St Georges Basin were characterised by low diversity with four and nine taxa recorded respectively in contrast to the sixteen taxa observed on the Botany Bay reefs. Results indicated no significant differences in percentage cover of taxa among reefs in either St Georges Basin or Lake Macquarie. In contrast, comparisons between individual Botany Bay reefs identified significant differences in the percentage cover of species between artificial reefs. Analysis of assemblage structure with reef age indicated discrete patterns among estuaries with an overall reduction in the percentage cover of filamentous turfing algae (FTA identified for all reef systems with an increase in reef age. Variations in environmental and physical conditions (turbidity, water flow, wave action and proximity to naturally occurring reef may have contributed to the observed differences in fouling assemblages between estuaries and between artificial reefs within Botany Bay.Estudos prévios que examinaram a dinâmica de sucessão em recifes artificiais foram focalizados nas comunidades de peixes, e sempre ignoraram o papel exercido pelos organismos incrustantes sobre a estruturação das comunidades associadas aos recifes artificiais. O presente estudo tem por objetivo

Safety culture development at Daya Bay NPP

International Nuclear Information System (INIS)

Zhang Shanming

2001-01-01

From view on Organization Behavior theory, the concept, development and affecting factors of safety culture are introduced. The focuses are on the establishment, development and management practice for safety culture at Daya Bay NPP. A strong safety culture, also demonstrated, has contributed greatly to improving performance at Daya Bay

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.

Bioaccumulation of heavy metals both in wild and mariculture food chains in Daya Bay, South China

Science.gov (United States)

Qiu, Yao-Wen

2015-09-01

Bioaccumulation and trophic transfer of heavy metals both in the natural marine ecosystem (seawater, sediment, coral reef, phytoplankton, macrophyte, shrimp, crab, shellfish, planktivorous and carnivorous fish) and in the mariculture ecosystem (compound feed, trash fish, farmed pompano and snapper) were studied at Daya Bay, a typical subtropical bay in Southern China. The levels of Cu, Zn, Pb and Cd in sediment were 11.7, 10.2, 53.8 and 2.8 times than those in coral reef, respectively. Pb and Zn levels were markedly higher in phytoplankton than in macrophyte, probably caused by the larger specific surface area in phytoplankton. The highest levels of Zn (98.1), Pb (1.87) and Cd (5.11 μg g-1 dw) in wild organisms were all found in clam (Veremolpa scabra), indicating that these metals were apt to bioaccumulate in shellfish. The average concentrations of Cu, Zn, Pb and Cd in wild fish were 3.7, 2.1, 0.4 and 22.2 times than those in farmed fish, confirming the "growth dilution" hypothesis in farmed fish. Heavy metal bioconcentration factors (BCFs) in algae, bioaccumulation factors (BAFs) in wild species and transfer factors (TFs) in organism were calculated and discussed. The results suggested that biologically essential Cu and Zn were easier to accumulate in fish than non-essential Cd. Concentrations of Cu, Zn and Cd were several times higher in wild fish than in farmed fish whereas the opposite was observed for Pb. This metal also showed the highest transfer factor from food, which means that special attention must be given to fish feed production in relation to metal contamination.

PENERAPAN ALGORITMA NAIVE BAYES UNTUK MENGKLASIFIKASI DATA NASABAH ASURANSI

Directory of Open Access Journals (Sweden)

Bustami Bustami

2014-01-01

Full Text Available Data mining adalah teknik yang memanfaatkan data dalam jumlah yang besar untuk memperoleh informasi berharga yang sebelumnya tidak diketahui dan dapat dimanfaatkan untuk pengambilan keputusan penting. Pada penelitian ini, penulis berusaha menambang data (data mining nasabah sebuah perusahaan asuransi untuk mengetahui lancar, kurang lancar atau tidak lancarnya nasabah tersebut. Data yang ada dianalisis menggunakan algoritma Naive Bayes. Naive Bayes merupakan salah satu meode pada probabilistic reasoning. Algoritma Naive Bayes bertujuan untuk melakukan klasifikasi data pada kelas tertentu, kemudian pola tersebut dapat digunakan untuk memperkirakan nasabah yang bergabung, sehingga perusahaan bisa mengambil keputusan menerima atau menolak calon nasabah tersebut. Kata Kunci : data mining, asuransi, klasifikasi, algoritma Naive Bayes

Tectonic structure and petroleum potential of TayabasBay southeast Luzon, Philippines

Science.gov (United States)

Bacud, Jaime; Moore, Aidan; Lee, Chao-Skiing

Tayabas Bay is one of four offshore Philippine areas where the Australian GeologicalSurvey Organization and the Philippine Department of Energy conducted a cooperative marine seismic, gravity, magnetic, bathymetry and geochemical survey. The project acquired new seismic data and reprocessed the 1983 World Bank seismic sections which were all integrated with previous oil company data. the absence of wells drilled offshore, interpretation of offshore seismic data was complemented by onshore well log information and stratigraphy of the Bondoc Peninsula. Geochemistry data, both offshore and onshore, were analyzed to confirm the presence of mature source rocks and hydrocarbon migration. A new seismic interpretation has revealed the structure of this tectonically active geologically complex area. A major structural feature interpreted in offshore Tayabas Bay was a N-NW-trending strike-slip fault which is believed to be a northern splay of the Sibuyan Sea Fault. The authors named this fault the Tayabas Bay Fault and due to its association with the Philippine Fault System the movement is assumed to be left-lateral. The present study suggested the presence of a prolific source rock in the Middle Miocene Vigo Formation and/or the Late Oligocene to Early Miocene Panaon Limestone. Oil and gas generation have been and are occurring in the Bondoc Sub-basin. Two groups of reservoirs were identified, the shelf carbonates beneath the Middle Miocene shales on the Marinduque Platform and the early Middle Miocene carbonates and basin-floor clastics near the base of the Vigo Formation. Carbonate reservoirs are believed to be present in traps formed when the Late Oligocene to Early Miocene carbonate reefs and shelf deposits of the Panaon Limestone were buried by the Middle Miocene shales. A later set of traps was formed and possibly superimposed by the intense deformation associated with the Philippine Fault System which has continued from the Late Pliocene up to the present. Evaluation

Automation in tube finishing bay

International Nuclear Information System (INIS)

Bhatnagar, Prateek; Satyadev, B.; Raghuraman, S.; Syama Sundara Rao, B.

1997-01-01

Automation concept in tube finishing bay, introduced after the final pass annealing of PHWR tubes resulted in integration of number of sub-systems in synchronisation with each other to produce final cut fuel tubes of specified length, tube finish etc. The tube finishing bay which was physically segregated into four distinct areas: 1. tube spreader and stacking area, 2. I.D. sand blasting area, 3. end conditioning, wad blowing, end capping and O.D. wet grinding area, 4. tube inspection, tube cutting and stacking area has been studied

Aerial radiometric and magnetic survey: Beeville/Bay City National Topographic Map, Texas Gulf Coast

International Nuclear Information System (INIS)

1979-01-01

As part of the National Uranium Resource Evaluation program Geodata International, Inc. of Dallas, Texas, conducted an airborne gamma ray and total magnetic field survey of Beeville/Bay City Quadrangle of the Texas Gulf Coast area. Volume 1 gives the description of the program and results, and volume 2 gives the flight line profile data and statistical analysis results. The Beeville/Bay City Map Sheet shows Tertiary and Quaternary-aged strata which are part of the coastal plain of the Gulf Coast Geosyncline. The Cenozoic sediments overlie Mesozoic, Paleozoic, and Precambrian rocks, and have a relatively gentle homoclinal dip toward the gulf. The Quaternary and Tertiary sediments of the map sheet overlie the western flank of the Houston-East Texas Embayment, the northeastern side of the Rio Grande Embayment, and the San Marcos Arch. Recent and Pleistocene sediments crop-out in the south and east, and are more extensive in the vicinity of the structural embayments. The Pliocene-aged Goliad Formation crops-out extensively to the northwest. Miocene and Eocene strata occur in the northwestern corner of the map sheet. The uranium deposits occur in the Tertiary strata, but are most intensely mined in the Eocene strata immediately to the west of the map sheet area

Application of EEM fluorescence spectroscopy in understanding of the "LIGA" phenomenon in the Bay of Biscay (France)

Science.gov (United States)

Parot, Jérémie; Susperregui, Nicolas; Rouaud, Vanessa; Dubois, Laurent; Anglade, Nathalie; Parlanti, Edith

2014-05-01

Marine mucilage is present in all oceans over the world, and in particular in the Mediterranean Sea and in the Pacific Ocean. Surface water warming and hydrodynamic processes can favor the coalescence of marine mucilage, large marine aggregates representing an ephemeral and extreme habitat for biota. DOM is a heterogeneous, complex mixture of compounds, including extracellular polymeric substances (EPS), with wide ranging chemical properties and it is well known to interact with pollutants and to affect their transport and their fate in aquatic environment. The LIGA French research program focuses on tracing colloidal dissolved organic matter (DOM) sources and cycling in the Bay of Biscay (South Western French coast). This ephemeral phenomenon (called "LIGA" in the South West of France) has been observed more than 750 times since 2010. It presents a great ecological impact on marine ecosystems and has been shown to be concomitant with the development of pathogen organisms. A one-year intensive survey of fluorescent DOM was undertaken. From April 2013 until May 2014, water samples were monthly collected from the Adour River (main fresh water inputs) and from 2 sites in the Bay of Biscay at 3 depths of the water column (surface water, at the maximum of chlorophyll-a, and deep water). Moreover, intensified samplings took place from the appearance of the phenomenon twice a week during 4 weeks. UV/visible absorbance and excitation emission matrix (EEM) fluorescence spectroscopy combined with PARAFAC and PCA analyses have been used to characterize colloidal DOM in the Bay of Biscay in order to estimate DOM sources as well as spatial and temporal variability of DOM properties. The preliminary results, obtained for about 70 samples of this survey, have already highlighted spatial and temporal variations of DOM optical properties and a peculiar fluorescent component (exc300nm/em338nm) was detected while the LIGA phenomenon arises. The appearance of this specific

46 CFR 7.110 - Mamala Bay, HI.

Science.gov (United States)

2010-10-01

... 46 Shipping 1 2010-10-01 2010-10-01 false Mamala Bay, HI. 7.110 Section 7.110 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY PROCEDURES APPLICABLE TO THE PUBLIC BOUNDARY LINES Hawaii § 7.110 Mamala Bay, HI. A line drawn from Barbers Point Light to Diamond Head Light. Pacific Coast ...

33 CFR 165.1187 - Security Zones; Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, San Francisco Bay...

Science.gov (United States)

2010-07-01

... Limited Access Areas Eleventh Coast Guard District § 165.1187 Security Zones; Golden Gate Bridge and the... Golden Gate Bridge and the San Francisco-Oakland Bay Bridge, in San Francisco Bay, California. (b... siren, radio, flashing light, or other means, the operator of a vessel shall proceed as directed. [COTP...

Differences between epiphytic assemblages on introduced Caulerpa taxifolia and coexisting eelgrass (Zostera capricorni in Botany Bay (NSW, Australia

Directory of Open Access Journals (Sweden)

Patricia Prado

2008-12-01

Full Text Available A preliminary study was conducted to assess the potential effects of introduced Caulerpa taxifolia (Caulerpales, Chlorophyta on the biodiversity and trophic functioning of seagrass systems in New South Wales, Australia. Epiphytic assemblages growing on fronds of C. taxifolia were compared to those on eelgrass Zostera capricorni (Aschers. leaves in zones where both species were coexisting. The study was conducted at three shallow sites (ca. 1 m depth in Botany Bay during austral spring. Assemblages on both C. taxifolia and Z. capricorni were dominated by epiphytic algae (ca. 65% of the total taxa but results showed significantly greater numbers on C. taxifolia compared to Z. capricorni as well as important differences among study sites. n-MDS ordinations and PERMANOVA analyses confirmed the existence of significant differences in the assemblage compositions of C. taxifolia and Z. capricorni as well as differences between times and sites. SIMPER analysis showed that animal composition made a higher contribution to dissimilarities between habitats compared to epiphytic algae (36% vs. 23% respectively. In particular, filter-feeding organisms, associated with surfaces such as ascidians (5 taxa and bryozoans (2 taxa emerged as important contributing taxa. Hence, our results suggest that introduced C. taxifolia from Botany Bay is a suitable substratum for settlement of epiphytes, at least during the study period, and that observed patterns are due to differences in habitat structure. Further research is necessary to determine the influence of seasonal processes, such as production of toxic secondary metabolites, in other invaded locations of New South Wales.

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.

Use of Geographic Information Systems to examine cumulative impacts of development on Mobile Bay, AL and Galveston Bay, TX

International Nuclear Information System (INIS)

Rosigno, P.F.; McNiff, M.E.; Watzin, M.C.; Ji, W.

1993-01-01

Databases from Mobile Bay, Alabama and Galveston Bay, Texas were compiled using ARC/INFO Geographic Information Systems (GIS) to examine the cumulative impacts from urbanization and industrialization on these two Gulf of Mexico estuaries. The databases included information on wetland habitats, pollution sources, metal contamination, bird-nesting sites, and oyster reefs, among others. A series of maps were used to represent the impacts within and between each ecosystem. These two estuaries share many similarities in the types of developmental pressures that each experience. However, difference in the magnitude of industrial activity, pollution loading, and urban growth coupled with distinct hydrodynamic and geochemical differences in sediment mineralogy, freshwater inflows and salinity regimens results in differing responses. With growing human population and extensive oil and gas development, the demands on Galveston Bay are quite different than those placed on Mobile Bay which has lower growth and less extensive oil and gas infrastructure. Mobile Bay tends to retain whatever contamination enters into the system because of the high levels of clay and organic carbon found in its sediment. Some of these chemicals bioaccumulate, posing an extra risk to natural resources. Geographic Information Systems provide natural resource managers with the technology to manage complex databases. The analytical and mapping capabilities of GIS can be used to consider cumulative effects in a regional context and to develop plans to protect ecologically sensitive areas

Hydrodynamics and water quality models applied to Sepetiba Bay

Science.gov (United States)

Cunha, Cynara de L. da N.; Rosman, Paulo C. C.; Ferreira, Aldo Pacheco; Carlos do Nascimento Monteiro, Teófilo

2006-10-01

A coupled hydrodynamic and water quality model is used to simulate the pollution in Sepetiba Bay due to sewage effluent. Sepetiba Bay has a complicated geometry and bottom topography, and is located on the Brazilian coast near Rio de Janeiro. In the simulation, the dissolved oxygen (DO) concentration and biochemical oxygen demand (BOD) are used as indicators for the presence of organic matter in the body of water, and as parameters for evaluating the environmental pollution of the eastern part of Sepetiba Bay. Effluent sources in the model are taken from DO and BOD field measurements. The simulation results are consistent with field observations and demonstrate that the model has been correctly calibrated. The model is suitable for evaluating the environmental impact of sewage effluent on Sepetiba Bay from river inflows, assessing the feasibility of different treatment schemes, and developing specific monitoring activities. This approach has general applicability for environmental assessment of complicated coastal bays.

Inputs and spatial distribution patterns of Cr in Jiaozhou Bay

Science.gov (United States)

Yang, Dongfang; Miao, Zhenqing; Huang, Xinmin; Wei, Linzhen; Feng, Ming

2018-03-01

Cr pollution in marine bays has been one of the critical environmental issues, and understanding the input and spatial distribution patterns is essential to pollution control. In according to the source strengths of the major pollution sources, the input patterns of pollutants to marine bay include slight, moderate and heavy, and the spatial distribution are corresponding to three block models respectively. This paper analyzed input patterns and distributions of Cr in Jiaozhou Bay, eastern China based on investigation on Cr in surface waters during 1979-1983. Results showed that the input strengths of Cr in Jiaozhou Bay could be classified as moderate input and slight input, and the input strengths were 32.32-112.30 μg L-1 and 4.17-19.76 μg L-1, respectively. The input patterns of Cr included two patterns of moderate input and slight input, and the horizontal distributions could be defined by means of Block Model 2 and Block Model 3, respectively. In case of moderate input pattern via overland runoff, Cr contents were decreasing from the estuaries to the bay mouth, and the distribution pattern was parallel. In case of moderate input pattern via marine current, Cr contents were decreasing from the bay mouth to the bay, and the distribution pattern was parallel to circular. The Block Models were able to reveal the transferring process of various pollutants, and were helpful to understand the distributions of pollutants in marine bay.

Bayes and Networks