WorldWideScience

Sample records for atolls

  1. Dose assessment at Bikini Atoll

    International Nuclear Information System (INIS)

    Robison, W.L.; Phillips, W.A.; Colsher, C.S.

    1977-01-01

    Bikini Atoll is one of two sites in the northern Marshall Islands that was used by the United States as testing grounds for the nuclear weapons program from 1946 to 1958. In 1969 a general cleanup began at Bikini Atoll. Subsistence crops, coconut and Pandanus fruit, were planted on Bikini and Eneu Islands, and housing was constructed on Bikini Island. A second phase of housing was planned for the interior of Bikini Island. Preliminary data indicated that external gamma doses in the interior of the island might be higher than in other parts of the island. Therefore, to select a second site for housing on the island with minimum external exposure, a survey of Bikini Atoll was conducted in June 1975. External gamma measurements were made on Bikini and Eneu Islands, and soil and vegetations samples collected to evaluate the potential doses via terrestrial food chains and inhalation. Estimates of potential dose via the marine food chain were based upon data collected on previous trips to the atoll. The terrestrial pathway contributes the greater percentage, external gamma exposure contributes the next highest, and inhalation and marine pathways contribute minor fractions of the total whole body and bone marrow doses. The radionuclides contributing the major fraction of the dose are 90 Sr and 137 Cs. All living patterns involving Bikini Island exceed federal guidelines for 30-yr population doses. The Eneu Island living pattern leads to doses that are slightly less than federal guidelines. All patterns evaluated for Bikini Atoll lead to higher doses than those on the southern islands at Enewetak Atoll

  2. Biosecurity Plan for Palmyra Atoll

    Science.gov (United States)

    Hathaway, Stacie A.; Fisher, Robert N.

    2010-01-01

    This Biosecurity Plan for Palmyra Atoll was developed for The Nature Conservancy (TNC) Palmyra Program to refine and expand goals and objectives developed through the Conservation Action Plan process. The Biosecurity Plan is one in a series of adaptive management plans designed to achieve TNC's mission toward the protection and enhancement of native wildlife and habitat. The Biosecurity Plan focuses on ecosystem security, and specifically identifies and addresses issues related to non-native and potentially invasive species. The Plan attempts to identify pathways of invasion and strategies for preventing or reducing new introductions. Overall, the Biosecurity Plan provides a framework to implement and track the progress of conservation and restoration goals related to non-native species on Palmyra Atoll. Palmyra Atoll is one of the Northern Line Islands in the Pacific Ocean southwest of the Hawai`ian Islands. It consists of many heavily vegetated islets arranged in a horseshoe pattern around four lagoons and surrounded by a coral reef. At present, Palmyra Atoll harbors various non-native or invasive species in the terrestrial and marine ecosystems. The most notable examples of terrestrial invasive species include coconut trees (Cocos nucifera) and black rats (Rattus rattus). Although it is unclear whether they are non-native, coconut trees are currently the most dominant plant across Palmyra Atoll. They compete with native plant species for space and resources, and are potentially detrimental to seabirds dependent on native vegetation. Black rats are known to predate ground-nesting seabirds and are likely responsible for the lack of burrowing seabird reproduction on Palmyra Atoll. The most notable example of a marine invasive species is the corallimorph (Rhodactis howsei). Although Rhodactis howsei is a native species, it can take advantage of human-altered habitat and significantly change the natural habitat by aggressively outcompeting native corals. Although the

  3. Resettlement of Bikini Atoll U.S. Nuclear Test Site

    International Nuclear Information System (INIS)

    Robinson, W.L.; Conrado, C.L.; Stuart, M.L.; Stoker, A.C.; Hamilton, T.F.

    1999-01-01

    The US conducted a nuclear testing program at Bikini and Enewetak Atolls in the Marshall Islands from 1946 through 1958. Several atolls, including Bikini, were contaminated as a result of the nuclear detonations. Since 1974 the authors have conducted an extensive research and monitoring program to determine the radiological conditions at the atolls, identify the critical radionuclides and pathways, estimate the radiological dose to current or resettling populations, and develop remedial measures to reduce the dose to atoll populations. This paper describes exposure pathways and radionuclides; composition of atoll soils; radionuclide transport and dose estimates; remedial measures; and reduction in dose from a combined option

  4. Radiological conditions at Bikini Atoll: Prospects for resettlement

    International Nuclear Information System (INIS)

    1998-01-01

    An international Advisory Group met at IAEA Headquarters in Vienna on 11-15 December 1995 for the purpose of reviewing the current radiological conditions at Bikini Atoll, Republic of the Marshall Islands, and advising on the prospects for rehabilitation of the atoll and resettlement of its indigenous population. The Advisory Group was convened by the IAEA in response to a request for technical assistance from the Government of the Marshall Islands within the framework of IAEA technical co-operation project MHL/9/003, 'Radiological Monitoring in Bikini Atoll'. The primary aim of this review was to assist the Bikinian people to form their own judgement on the radiological conditions at their atoll and on the prospects for resettling there, should they so desire. At the meeting, the Advisory Group benefited greatly from the participation of a delegation from the Marshall Islands. At the request of the Government of the Marshall Islands, the international review was limited to Bikini Atoll and did not extend to other atolls, islands and isles affected by radioactive fallout from the testing. Moreover, within Bikini Atoll, it was concentrated on Bikini Island, where the Bikinian population formerly resided. The review relates to the prevailing radiological circumstances and their implications for the future habitability of the atoll. It is not intended to include the retrospective assessment of the past radiological impact of nuclear testing. The United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) has routinely estimated, and reported to the United Nations General Assembly, radiation levels and effects attributable to nuclear weapon testing, including the tests carried out in the territory of the Marshall Islands. Some of the UNSCEAR estimates have been included in the report, but only for the sake of completeness

  5. Multidecadal shoreline changes of atoll islands in the Marshall Islands

    Science.gov (United States)

    Ford, M.

    2012-12-01

    Atoll islands are considered highly vulnerable to the impacts of continued sea level rise. One of the most commonly predicted outcomes of continued sea level rise is widespread and chronic shoreline erosion. Despite the widespread implications of predicted erosion, the decadal scale changes of atoll island shorelines are poorly resolved. The Marshall Islands is one of only four countries where the majority of inhabited land is comprised of reef and atoll islands. Consisting of 29 atolls and 5 mid-ocean reef islands, the Marshall Islands are considered highly vulnerable to the impacts of sea level rise. A detailed analysis of shoreline change on over 300 islands on 10 atolls was undertaken using historic aerial photos (1945-1978) and modern high resolution satellite imagery (2004-2012). Results highlight the complex and dynamic nature of atoll islands, with significant shifts in shoreline position observed over the period of analysis. Results suggest shoreline accretion is the dominant mode of change on the islands studied, often associated with a net increase in vegetated island area. However, considerable inter- and intra-atoll variability exists with regards to shoreline stability. Findings are discussed with respect to island morphodynamics and potential hazard mitigation and planning responses within atoll settings.

  6. An Ecological Assessment of Johnston Atoll

    Science.gov (United States)

    2012-01-01

    limits Short-nose Wrasse, Macropharyngodon geoffroy Global Climate Event causes Coral Bleaching Research by Anne L. Cohen, P. S. Lobel, and Gabrielle L...L. Tomasky. An unusual event of Coral bleaching on Johnston Atoll, Central Pacific Ocean. Biological Bulletin 193:276-279. On 10 September 1996...extensive coral bleaching was noted on Johnston Atoll. Between September 1996 and March 1997 the nature and extent of the bleaching , as well as the

  7. Bikini Atoll groundwater development

    International Nuclear Information System (INIS)

    Peterson, F.L.

    1985-01-01

    Nuclear weapons testing during the 1950's has left the soil and ground water on Bikini Atoll contaminated with cesium-137, and to a lesser extent, strontium-90. Plans currently are underway for the clean-up and resettlement of the atoll by removal of approximately the upper 30 cm of soil. Any large-scale resettlement program must include provisions for water supply. This will be achieved principally by catchment and storage of rain water, however, since rainfall in Bikini is highly seasonal and droughts occur frequently, ground water development must also be considered. The quantity of potable ground water that can be developed is limited by its salinity and radiological quality. The few ground water samples available from Bikini, which have been collected from only about the top meter of the groundwater body, indicate that small bodies of potable ground water exist on Bikini and Eneu, the two principal living islands, but that cesium and strontium in the Bikioni ground water exceed drinking water standards. In order to make a reasonable estimate of the ground water development potential for the atoll, some 40 test boreholes will be drilled during July/August 1985, and a program of water quality monitoring initiated. This paper will describe preliminary results of the drilling and monitoring work

  8. Estimating the Ground Water Resources of Atoll Islands

    Directory of Open Access Journals (Sweden)

    Arne E. Olsen

    2010-01-01

    Full Text Available Ground water resources of atolls, already minimal due to the small surface area and low elevation of the islands, are also subject to recurring, and sometimes devastating, droughts. As ground water resources become the sole fresh water source when rain catchment supplies are exhausted, it is critical to assess current groundwater resources and predict their depletion during drought conditions. Several published models, both analytical and empirical, are available to estimate the steady-state freshwater lens thickness of small oceanic islands. None fully incorporates unique shallow geologic characteristics of atoll islands, and none incorporates time-dependent processes. In this paper, we provide a review of these models, and then present a simple algebraic model, derived from results of a comprehensive numerical modeling study of steady-state atoll island aquifer dynamics, to predict the ground water response to changes in recharge on atoll islands. The model provides an estimate thickness of the freshwater lens as a function of annual rainfall rate, island width, Thurber Discontinuity depth, upper aquifer hydraulic conductivity, presence or absence of a confining reef flat plate, and in the case of drought, time. Results compare favorably with published atoll island lens thickness observations. The algebraic model is incorporated into a spreadsheet interface for use by island water resources managers.

  9. Terrestrial forest management plan for Palmyra Atoll

    Science.gov (United States)

    Hathaway, Stacie A.; McEachern, Kathryn; Fisher, Robert N.

    2011-01-01

    This 'Terrestrial Forest Management Plan for Palmyra Atoll' was developed by the U.S. Geological Survey (USGS) for The Nature Conservancy (TNC) Palmyra Program to refine and expand goals and objectives developed through the Conservation Action Plan process. It is one in a series of adaptive management plans designed to achieve TNC's mission toward the protection and enhancement of native wildlife and habitat. The 'Terrestrial Forest Management Plan for Palmyra Atoll' focuses on ecosystem integrity and specifically identifies and addresses issues related to assessing the status and distribution of resources, as well as the pressures acting upon them, most specifically nonnative and potentially invasive species. The plan, which presents strategies for increasing ecosystem integrity, provides a framework to implement and track the progress of conservation and restoration goals related to terrestrial resources on Palmyra Atoll. The report in its present form is intended to be an overview of what is known about historical and current forest resources; it is not an exhaustive review of all available literature relevant to forest management but an attempt to assemble as much information specific to Palmyra Atoll as possible. Palmyra Atoll is one of the Northern Line Islands in the Pacific Ocean southwest of the Hawai`ian Islands. It consists of many heavily vegetated islets arranged in a horseshoe pattern around four lagoons and surrounded by a coral reef. The terrestrial ecosystem consists of three primary native vegetation types: Pisonia grandis forest, coastal strand forest, and grassland. Among these vegetation types, the health and extent of Pisonia grandis forest is of particular concern. Overall, the three vegetation types support 25 native plant species (two of which may be extirpated), 14 species of sea birds, six shore birds, at least one native reptile, at least seven native insects, and six native land crabs. Green and hawksbill turtles forage at Palmyra Atoll

  10. Individual Radiation Protection Monitoring in the Marshall Islands. Utrok Atoll (2010-2012)

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Kehl, S. R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Martinelli, R. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hickman, R. E. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hickman, D. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tumey, S. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Brown, T. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Langston, R. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tamblin, M. W. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Tibon, S. [Utrok Whole Body Counting Facility, Majuro Atoll (Republic of the Marshall Islands); Chee, L. [Utrok Whole Body Counting Facility, Majuro Atoll (Republic of the Marshall Islands); Aisek, Jr., A. [Utrok Whole Body Counting Facility, Majuro Atoll (Republic of the Marshall Islands); DeDrum, Z. [Utrok Whole Body Counting Facility, Majuro Atoll (Republic of the Marshall Islands); Mettao, M. [Utrok Whole Body Counting Facility, Majuro Atoll (Republic of the Marshall Islands); Henson, J. [Utrok Whole Body Counting Facility, Majuro Atoll (Republic of the Marshall Islands)

    2014-12-15

    As a hard copy supplement to the Marshall Islands Program website (https://marshallislands.llnl.gov), this document provides an overview of the individual radiological surveillance monitoring program established in support of residents of Utrōk Atoll and nonresident citizens of the Utrōk Atoll population group, along with full disclosure of verified measurement data (2010-2012). The Utrōk Atoll Whole Body Counting Facility has been temporarily stationed on Majuro Atoll and, in cooperation with the Utrōk Atoll Local Government, serves as a national radiological facility open to the general public.

  11. Processing plutonium-contaminated soil on Johnston Atoll

    International Nuclear Information System (INIS)

    Moroney, K.; Moroney, J. III; Turney, J.

    1994-01-01

    This article describes a cleanup project to process plutonium- and americium-contaminated soil on Johnston Atoll for volume reduction. Thermo Analytical's (TMA's) segmented gate system (SGS) for this remedial operation has been in successful on-site operation since 1992. Topics covered include the basis for development, a description of the Johnston Atoll; the significance of results; the benefits of the technology; applicability to other radiologically contaminated sites. 7 figs., 1 tab

  12. Evaluation of plutonium at Enewetak Atoll

    International Nuclear Information System (INIS)

    Wilson, D.W.; Ng, Y.C.; Robison, W.L.

    1975-01-01

    An extensive survey was carried out in 1972 to 1973 to assess the current radiological status of Enewetok Atoll. The radionuclides detected in the Atoll environment were studied for their potential contributions to the dose commitment of the returning population according to several pathways of exposure. Plutonium was detected in air and in the terrestrial and aquatic environment at concentrations that varied from background levels due to world-wide fallout to levels several orders-of-magnitude above. The dose commitments from plutonium via the terrestrial food chain and inhalation vary according to the postulated living pattern. The dosages via marine foods can be expected to be insensitive to living pattern and to exceed those via terrestrial foods. Plutonium would contribute nearly all of the dosage via inhalation, but this pathway ranks low in overall importance compared with the food-chain and external-dose pathways. Although the potential dose from plutonium via all pathways is low relative to that from 60 Co, 90 Sr and 137 Cs, plutonium will still remain in the Atoll environment after the other makor isotopes have decayed away. (author)

  13. Spatial and temporal controls of atoll island inundation: implications for urbanized atolls in the Marshall Islands.

    Science.gov (United States)

    Ford, M.; Becker, J. M.; Merrifield, M. A.

    2012-12-01

    Atoll islands are highly vulnerable to a range of inundation hazards. The impacts of such hazards are expected to be magnified as a result of continued sea-level rise. Both recent and historic inundation events provide unique insights into the requisite conditions necessary to initiate island inundation. A number of recent and historic inundation events are presented in order to examine the oceanographic and meteorological conditions driving inundation of a densely populated, urbanized atoll in the central Pacific. Analysis of inundation events suggests that a number of key drivers contribute to the spatial and temporal extent of island inundation, with unique degrees of predictability and resultant impact signatures apparent on island geomorphology and local anthropogenic activities. Results indicate three distinct drivers of inundation hazards exist. Firstly, tropical storms and typhoons elevate sea level through inverse barometric setup, wind setup and a range of wave driven processes and have caused considerable impact on atolls within the Marshall Islands. Secondly, super-elevated sea level conditions resulting from the combination of seasonal high tides and quasi-cyclical La Nina conditions drive inundation of low-lying lagoon facing coastal areas. Thirdly, long period swell conditions, typically generated by distant storms, can elevate reef-flat water levels through wave setup and infragravity wave oscillations. Such wave conditions can over wash the ocean-facing island ridge, often inundating large sections of the island. Reef-flat wave conditions are tidally modulated, with inundation events typically occurring around high tide. However, the two most recent destructive swell-driven inundation events have occurred while tide levels were significantly lower than spring tide levels, suggesting high water levels are not a necessary prerequisite for wave-driven inundation. The different modes of inundation are discussed and grounded within recent and historic

  14. Atoll-scale patterns in coral reef community structure: Human signatures on Ulithi Atoll, Micronesia.

    Science.gov (United States)

    Crane, Nicole L; Nelson, Peter; Abelson, Avigdor; Precoda, Kristin; Rulmal, John; Bernardi, Giacomo; Paddack, Michelle

    2017-01-01

    The dynamic relationship between reefs and the people who utilize them at a subsistence level is poorly understood. This paper characterizes atoll-scale patterns in shallow coral reef habitat and fish community structure, and correlates these with environmental characteristics and anthropogenic factors, critical to conservation efforts for the reefs and the people who depend on them. Hierarchical clustering analyses by site for benthic composition and fish community resulted in the same 3 major clusters: cluster 1-oceanic (close proximity to deep water) and uninhabited (low human impact); cluster 2-oceanic and inhabited (high human impact); and cluster 3-lagoonal (facing the inside of the lagoon) and inhabited (highest human impact). Distance from village, reef exposure to deep water and human population size had the greatest effect in predicting the fish and benthic community structure. Our study demonstrates a strong association between benthic and fish community structure and human use across the Ulithi Atoll (Yap State, Federated States of Micronesia) and confirms a pattern observed by local people that an 'opportunistic' scleractinian coral (Montipora sp.) is associated with more highly impacted reefs. Our findings suggest that small human populations (subsistence fishing) can nevertheless have considerable ecological impacts on reefs due, in part, to changes in fishing practices rather than overfishing per se, as well as larger global trends. Findings from this work can assist in building local capacity to manage reef resources across an atoll-wide scale, and illustrates the importance of anthropogenic impact even in small communities.

  15. Geochemistry of transuranic elements at Bikini Atoll

    International Nuclear Information System (INIS)

    Schell, W.R.; Lowman, F.G.; Marshall, R.P.

    1980-01-01

    The distribution of transuranic and other radionuclides in the marine environment at Bikini Atoll was studied to better understand the geochemical cycling of radionuclides produced by nuclear testing between 1946 and 1958. The reef areas, which are washed continually by clean ocean water, have low levels of radionuclide concentrations. Radionuclides are contained in fallout particles of pulverized coral. In the water these particles may dissolve, be transported by currents within the Atoll, or enter the North Equatorial Current by tidal exchange of water in the lagoon. The transuranic elements are distributed widely in sediments over the northwest quadrant of the Atoll, which suggests that this area serves as a settling basin for particles. The distribution of plutonium in the water column indicates that plutonium in the sediments is released to the bottom waters and then is transported and diluted by the prevailing currents. Upon interaction with the lagoon environment, plutonium occurs in several physicochemical states. Laboratory tests and field studies at Bikini show that approximately 15% of the plutonium is associated with the colloidal fraction

  16. Microbial ecology of four coral atolls in the Northern Line Islands.

    Directory of Open Access Journals (Sweden)

    Elizabeth A Dinsdale

    Full Text Available Microbes are key players in both healthy and degraded coral reefs. A combination of metagenomics, microscopy, culturing, and water chemistry were used to characterize microbial communities on four coral atolls in the Northern Line Islands, central Pacific. Kingman, a small uninhabited atoll which lies most northerly in the chain, had microbial and water chemistry characteristic of an open ocean ecosystem. On this atoll the microbial community was equally divided between autotrophs (mostly Prochlorococcus spp. and heterotrophs. In contrast, Kiritimati, a large and populated ( approximately 5500 people atoll, which is most southerly in the chain, had microbial and water chemistry characteristic of a near-shore environment. On Kiritimati, there were 10 times more microbial cells and virus-like particles in the water column and these microbes were dominated by heterotrophs, including a large percentage of potential pathogens. Culturable Vibrios were common only on Kiritimati. The benthic community on Kiritimati had the highest prevalence of coral disease and lowest coral cover. The middle atolls, Palmyra and Tabuaeran, had intermediate densities of microbes and viruses and higher percentages of autotrophic microbes than either Kingman or Kiritimati. The differences in microbial communities across atolls could reflect variation in 1 oceaonographic and/or hydrographic conditions or 2 human impacts associated with land-use and fishing. The fact that historically Kingman and Kiritimati did not differ strongly in their fish or benthic communities (both had large numbers of sharks and high coral cover suggest an anthropogenic component in the differences in the microbial communities. Kingman is one of the world's most pristine coral reefs, and this dataset should serve as a baseline for future studies of coral reef microbes. Obtaining the microbial data set, from atolls is particularly important given the association of microbes in the ongoing degradation

  17. Microbial Ecology of Four Coral Atolls in the Northern Line Islands

    Science.gov (United States)

    Smriga, Steven; Edwards, Robert A.; Angly, Florent; Wegley, Linda; Hatay, Mark; Hall, Dana; Brown, Elysa; Haynes, Matthew; Krause, Lutz; Sala, Enric; Sandin, Stuart A.; Thurber, Rebecca Vega; Willis, Bette L.; Azam, Farooq; Knowlton, Nancy; Rohwer, Forest

    2008-01-01

    Microbes are key players in both healthy and degraded coral reefs. A combination of metagenomics, microscopy, culturing, and water chemistry were used to characterize microbial communities on four coral atolls in the Northern Line Islands, central Pacific. Kingman, a small uninhabited atoll which lies most northerly in the chain, had microbial and water chemistry characteristic of an open ocean ecosystem. On this atoll the microbial community was equally divided between autotrophs (mostly Prochlorococcus spp.) and heterotrophs. In contrast, Kiritimati, a large and populated (∼5500 people) atoll, which is most southerly in the chain, had microbial and water chemistry characteristic of a near-shore environment. On Kiritimati, there were 10 times more microbial cells and virus-like particles in the water column and these microbes were dominated by heterotrophs, including a large percentage of potential pathogens. Culturable Vibrios were common only on Kiritimati. The benthic community on Kiritimati had the highest prevalence of coral disease and lowest coral cover. The middle atolls, Palmyra and Tabuaeran, had intermediate densities of microbes and viruses and higher percentages of autotrophic microbes than either Kingman or Kiritimati. The differences in microbial communities across atolls could reflect variation in 1) oceaonographic and/or hydrographic conditions or 2) human impacts associated with land-use and fishing. The fact that historically Kingman and Kiritimati did not differ strongly in their fish or benthic communities (both had large numbers of sharks and high coral cover) suggest an anthropogenic component in the differences in the microbial communities. Kingman is one of the world's most pristine coral reefs, and this dataset should serve as a baseline for future studies of coral reef microbes. Obtaining the microbial data set, from atolls is particularly important given the association of microbes in the ongoing degradation of coral reef ecosystems

  18. Atoll mangroves and associated flora from Republic of Maldives, Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Jagtap, T.G.; Untawale, A.G.

    of the north atolls. Male' atoll was totally devoid of mangroves due to their large scale reclamation mainly for urbanisation and tourism. Mangrove flora comprised of 12 species and was dominated by Bruguiera cylindrica followed by Lumnitzera racemosa, Ceriops...

  19. Atoll-scale patterns in coral reef community structure: Human signatures on Ulithi Atoll, Micronesia.

    Directory of Open Access Journals (Sweden)

    Nicole L Crane

    Full Text Available The dynamic relationship between reefs and the people who utilize them at a subsistence level is poorly understood. This paper characterizes atoll-scale patterns in shallow coral reef habitat and fish community structure, and correlates these with environmental characteristics and anthropogenic factors, critical to conservation efforts for the reefs and the people who depend on them. Hierarchical clustering analyses by site for benthic composition and fish community resulted in the same 3 major clusters: cluster 1-oceanic (close proximity to deep water and uninhabited (low human impact; cluster 2-oceanic and inhabited (high human impact; and cluster 3-lagoonal (facing the inside of the lagoon and inhabited (highest human impact. Distance from village, reef exposure to deep water and human population size had the greatest effect in predicting the fish and benthic community structure. Our study demonstrates a strong association between benthic and fish community structure and human use across the Ulithi Atoll (Yap State, Federated States of Micronesia and confirms a pattern observed by local people that an 'opportunistic' scleractinian coral (Montipora sp. is associated with more highly impacted reefs. Our findings suggest that small human populations (subsistence fishing can nevertheless have considerable ecological impacts on reefs due, in part, to changes in fishing practices rather than overfishing per se, as well as larger global trends. Findings from this work can assist in building local capacity to manage reef resources across an atoll-wide scale, and illustrates the importance of anthropogenic impact even in small communities.

  20. Radionuclides in sediments and seawater at Rongelap Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Robison, W.L.; Eagle, R.J.; Brunk, J.L.

    1998-03-01

    The present concentrations and distributions of long-lived, man-made radionuclides in Rongelap Atoll lagoon surface sediments, based on samples collected and analyzed in this report. The radionuclides were associated with debris generated with the 1954 Bravo thermonuclear test at Bikini Atoll. Presently, only {sup 90}Sr and the transuranic radionuclides are found associated with the surface sediments in any quantity. Other radionuclides, including {sup 60}Co and {sup 137} Cs, are virtually absent and have either decayed or migrated from the deposits to the overlying seawater. Present inventories of {sup 241}Am and {sup 249+240}Pu in the surface layer at Rongelap are estimated to be 3% of the respective inventories in surface sediments from Bikini Atoll. There is a continuous slow release of the transuranics from the sediments back to the water column. The inventories will only slowly change with time unless the chemical-physical processes that now regulate this release to the water column are changed or altered.

  1. Evaluation of atrazine plus isoxaflutole (Atoll®) mixture for weed ...

    African Journals Online (AJOL)

    Field experiments were set up in three ecological zones of southwestern Nigeria to evaluate the effectiveness of Atoll® (atrazine + isoxaflutole), a new herbicide mixture, for weed control in maize. Crop i njury rating indicated pronounced phytotoxic effect on crops from 1.34 to 1.61 kg a.i. ha-1 Atoll in all locations. Acceptable ...

  2. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 1. Radionuclide concentrations measured in the terrestrial environment of the atolls

    International Nuclear Information System (INIS)

    1998-08-01

    This report provides technical details of the terrestrial sampling and measurement campaign undertaken as part of the Study of the Radiological Situation at the Atolls of Mururoa, Fangataufa by the Terrestrial Working Group. The primary objective of this group was to evaluate existing French data on the presence of environmental radionuclides on the atolls of Mururoa, Fangataufa and Tureia in French Polynesia. All aspects of the terrestrial environments of Mururoa and Fangataufa Atolls - the sites of atmospheric and underground nuclear tests - were included in the sampling programme. Tureia Atoll - the nearest inhabited island - was also included in the sampling programme, in order to determine whether deposits from atmospheric testing are detectable there. The task required the co-operation of many different parties in order to provide the supporting logistics for the sampling campaign and the expertise for analysing the different radionuclides of interest in the samples collected. Samples were analysed by members of the IAEA's co-ordinated international network of Analytical Laboratories for Measuring Environmental Radioactivity (ALMERA) and the Agency's laboratories, Seibersdorf. Samples were also sent to the French Service Mixte de Surveillance Radiologique et Biologique (SMSRB)

  3. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 2. Radionuclide concentrations measured in the aquatic environment of the atolls

    International Nuclear Information System (INIS)

    1998-08-01

    A marine monitoring programme was carried out within the framework of the IAEA's project entitled ''Study of the Radiological Situation at Mururoa and Fangataufa Atolls'' with the aim of assessing present radionuclide concentrations in the marine environment of Mururoa and Fangataufa Atolls. The terms of reference of the marine working group (WG2) included a review of the data provided by the French authorities on radionuclide distributions in the littoral and sub-littoral environments at the atolls. Further, using accredited international laboratories, it was decided to carry out sufficient and new independent monitoring work at and around the atolls in order to validate existing French data and, the same time, to provide a representative and high quality data set on current radionuclide concentrations in the marine environment, with particular reference to the requirement of Task Group A for radiological assessment purposes. This work included measurements of the current radionuclide concentrations in the marine environment, and estimation of concentration factors and K d values appropriate for the region. The variations in activity concentrations in the lagoons over the past few years are discussed, and the likely sources of activity implied by these data are identified where possible

  4. External radiation survey and dose predictions for Rongelap, Utirik, Rongerik, Ailuk, and Wotje Atolls

    International Nuclear Information System (INIS)

    Greenhouse, N.A.; Miltenberger, R.P.

    1977-01-01

    External radiation measurements were made at several atolls in the northern Marshall Islands, which are known or suspected to have been the recipients of tropospheric fallout during the Pacific Testing Programs. Sufficient data were available to ascertain realistic dose predictions for the inhabitants of Rongelap and Utirik Atolls where the 30 year integral doses from external sources exclusive of background radiation were 0.65 and 0.06 rem respectively. These estimates are based on realistic life-style models based on observations of each atoll community. Ailuk and Wotje Atolls were found to be represenatives of regional background radiation levels

  5. Marine radioactivity assessment of Mururoa and Fangataufa atolls

    International Nuclear Information System (INIS)

    Povinec, P.P.; Dovlete, C.; Gastaud, J.; Ikeuchi, Y.; Wee Kwong, L.L.; Mulsow, S.; Pettersson, H.; Woodhead, D.; Blowers, P.; Bonfield, R.; Smedley, P.; Taylor, B.; Cooper, M.; Chen, Q.; Dahlgaard, H.; Fox, V.; Morgenstern, U.; Taylor, C.; Froehlich, K.; Groening, M.; Hamilton, T.; Kanisch, G.; Krueger, A.; Matthews, M.; Tinker, R.

    1999-01-01

    The International Atomic Energy Agency (IAEA) carried out an international project 'The Study of the Radiological Situation at the Atolls of Mururoa and Fangataufa' with the aim of assessing the present and future radiological situation at the atolls and making recommendations for either monitoring or remedial actions if they are deemed necessary. The paper concentrates on marine radioactivity aspects and gives an estimation of present radionuclide concentrations in water, sediment and biota of the Mururoa and Fangataufa lagoons and the surrounding ocean. The dominant radionuclide in both lagoons is Pu in sediments (the total inventory is approximately 30 TBq). A decline in radionuclide concentrations has been observed in recent years in lagoon water, with the exception of 3H and 90Sr, for which a contribution from underground sources is to be expected. Radionuclide concentrations in biota from the lagoons and the surrounding ocean are low and consistent with previous measurements. The observed radionuclide concentrations in both lagoons imply that no radiological risk exists for hypothetical inhabitants of Mururoa and Fangataufa Atolls

  6. Hydrogeology and management of freshwater lenses on atoll islands: Review of current knowledge and research needs

    Science.gov (United States)

    Werner, Adrian D.; Sharp, Hannah K.; Galvis, Sandra C.; Post, Vincent E. A.; Sinclair, Peter

    2017-08-01

    On atoll islands, fresh groundwater occurs as a buoyant lens-shaped body surrounded by saltwater derived from the sea, forming the main freshwater source for many island communities. A review of the state of knowledge of atoll island groundwater is overdue given their susceptibility to adverse impacts, and the task to address water access and sanitation issues within the United Nations' Sustainable Development Goals framework before the year 2030. In this article, we review available literature to summarise the key processes, investigation techniques and management approaches of atoll island groundwater systems. Over fifty years of investigation has led to important advancements in the understanding of atoll hydrogeology, but a paucity of hydrogeological data persists on all but a small number of atoll islands. We find that the combined effects of buoyancy forces, complex geology, tides, episodic ocean events, strong climatic variability and human impacts create highly dynamic fresh groundwater lenses. Methods used to quantify freshwater availability range from simple empirical relationships to three-dimensional density-dependent models. Generic atoll island numerical models have proven popular in trying to unravel the individual factors controlling fresh groundwater lens behaviour. Major challenges face the inhabitants and custodians of atoll island aquifers, with rising anthropogenic stresses compounded by the threats of climate variability and change, sea-level rise, and some atolls already extracting freshwater at or above sustainability limits. We find that the study of atoll groundwater systems remains a critical area for further research effort to address persistent knowledge gaps, which lead to high uncertainties in water security issues for both island residents and surrounding environs.

  7. Neogene biostratigraphy and paleoenvironments of Enewetak Atoll, equatorial Pacific Ocean

    Science.gov (United States)

    Cronin, T. M.; Bybell, L.M.; Brouwers, E.M.; Gibson, T.G.; Margerum, R.; Poore, R.Z.

    1991-01-01

    Micropaleontologic analyses of Neogene sediments from Enewetak Atoll, Marshall Islands, provide data on the age of lagoonal deposits, stratigraphic disconformities and the paleoenvironmental and subsidence history of the atoll. Benthic foraminifers, planktic foraminifers, calcareous nannofossils and ostracodes were studied from six boreholes, the deepest penetrating 1605 feet below the lagoon floor into upper Oligocene strata. The Oligocene-Miocene boundary occurs at about 1200 ft below the lagoon floor. The early and middle Miocene is characterized by brief periods of deposition and numerous hiatuses. Ostracodes and benthic foraminifers indicate a shallow-marine reefal environment with occasional brackish water conditions. Upper Miocene and lower Pliocene deposits placed in calcareous nannofossil Zones NN9-15 and in planktic foraminifer Zones N16-19 contain species-rich benthic microfaunas which indicate alternating reefal and brackish water mangrove environments. The upper Pliocene contains at least two major depositional hiatuses that coincide with a major faunal turnover in benthic foraminiferal and ostracode assemblages. The Quaternary is characterized by benthic microfaunas similar to those of modern atoll lagoons and is punctuated by at least 11 disconformities which signify periods of low sea level. Atoll subsidence rates during the last 10 Ma averaged 30 to 40 m/m.y. ?? 1991 Elsevier Science Publishers B.V. All rights reserved.

  8. Propiedades fisicoquímicas y sensoriales de harinas para preparar atole de amaranto

    OpenAIRE

    Contreras López, Elizabeth; Jaimez Ordaz, Judith; Porras Martínez, Griselda; Juárez Santillán, Luis Felipe; Añorve Morga, Javier; Villanueva Rodríguez, Socorro

    2010-01-01

    El atole es una bebida prehispánica mexicana tradicionalmente preparada con maíz; sin embargo cereales como el arroz y el amaranto también han sido usados empleados. El objetivo fue caracterizar las propiedades fisicoquímicas y sensoriales de una harina para preparar una bebida (atole) a base de amaranto a fin de determinar su aporte nutricional. El análisis bromatológico del atole de amaranto y de las marcas comerciales (a base de maíz y arroz) fue realizado siguiendo las técnicas de la AOAC...

  9. 78 FR 32996 - Western Pacific Fisheries; Fishing in the Marianas Trench, Pacific Remote Islands, and Rose Atoll...

    Science.gov (United States)

    2013-06-03

    ... Islands, and Rose Atoll Marine National Monuments AGENCY: National Marine Fisheries Service (NMFS..., and Rose Atoll Marine National Monuments. The intent of this rule is to implement fishery management... Islands Monument, and Proclamation 8337 established the Rose Atoll Monument. The Proclamations define the...

  10. 78 FR 12015 - Western Pacific Fisheries; Fishing in the Marianas Trench, Pacific Remote Islands, and Rose Atoll...

    Science.gov (United States)

    2013-02-21

    ... Islands, and Rose Atoll Marine National Monuments AGENCY: National Marine Fisheries Service (NMFS..., Pacific Remote Islands, and Rose Atoll Marine National Monuments. The proposed rule is intended to...). Proclamation 8337 of January 6, 2009, ``Establishment of the Rose Atoll Marine National Monument'' (74 FR 1577...

  11. 78 FR 7385 - Western Pacific Fisheries; Fishing in the Marianas Trench, Pacific Remote Islands, and Rose Atoll...

    Science.gov (United States)

    2013-02-01

    ...-BA98 Western Pacific Fisheries; Fishing in the Marianas Trench, Pacific Remote Islands, and Rose Atoll... Presidential proclamations that created the Marianas Trench, Pacific Remote Islands, and Rose Atoll Marine..., 2009). Proclamation 8337 of January 6, 2009, ``Establishment of the Rose Atoll Marine National Monument...

  12. Aerial radiological and photographic survey of eleven atolls and two islands within the Northern Marshall Islands. Dates of surveys, July-November 1978

    International Nuclear Information System (INIS)

    1981-06-01

    An aerial radiological survey was conducted over eleven atolls and two islands within the northern Marshall Islands between September and November 1978. This survey was part of a comprehensive radiological survey, which included extensive terrestrial and marine sampling, to determine possible residual contamination which might remain as a result of the United States nuclear testing program conducted at Bikini Enewetak Atolls between 1946 and 1958. A similar survey was conducted at Enewetak Atoll in 1972. The present survey covered those atolls known to have received direct fallout from the Bravo event, conducted in March 1954 at Bikini Atoll. These included Bikini, Rongelap, Rongerik, Ailinginae, Bikar, Taka, and Utirik Atolls. In addition, several atolls and islands which might have been at the fringes of the Bravo fallout were also surveyed, including Likiep and Ailuk Atolls, Jemo and Mejit Islands, and Wotho Atoll. Ujelang Atoll, which lies approximately 200 km southwest of Enewetak, was also surveyed. Island-averaged terrestrial exposure rates in the range of 30 to 50 μR/h were observed over parts of Bikini Atoll, including Bikini Island, and over the northern part of Rongelap Atoll. Levels over southern Rongelap and over Rongerik Atoll ranged from 4 to 7 μR/h. Levels were somewhat lower at Ailinginae Atoll (approximately 2 μR/h) and at Utirik Atoll (approximately 0.7 μR/h). The variations observed were consistent with what might be expected from the fallout pattern of the Bravo event. Levels at Ailuk, Likiep, Wotho and Ujelang Atolls and at Mejit and Jemo Islands were consistent with 137 Cs activity, due to worldwide fallout, observed within the United States and at other locations in the central Pacific. These four atolls and the two islands, therefore, do not appear to have recieved any significant direct contamination from the Bravo event or the other tests conducted at Bikini and Enewetak Atolls

  13. CRED REA Algal Assessments, Johnston Atoll 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 17 sites at Johnston Atoll in...

  14. CRED REA Algal Assessments Wake Atoll, 2007

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 12 sites at Wake Atoll in April...

  15. Future Reef Growth Can Mitigate Physical Impacts of Sea-Level Rise on Atoll Islands

    Science.gov (United States)

    Beetham, Edward; Kench, Paul S.; Popinet, Stéphane

    2017-10-01

    We present new detail on how future sea-level rise (SLR) will modify nonlinear wave transformation processes, shoreline wave energy, and wave driven flooding on atoll islands. Frequent and destructive wave inundation is a primary climate-change hazard that may render atoll islands uninhabitable in the near future. However, limited research has examined the physical vulnerability of atoll islands to future SLR and sparse information are available to implement process-based coastal management on coral reef environments. We utilize a field-verified numerical model capable of resolving all nonlinear wave transformation processes to simulate how future SLR will modify wave dissipation and overtopping on Funafuti Atoll, Tuvalu, accounting for static and accretionary reef adjustment morphologies. Results show that future SLR coupled with a static reef morphology will not only increase shoreline wave energy and overtopping but will fundamentally alter the spectral composition of shoreline energy by decreasing the contemporary influence of low-frequency infragravity waves. "Business-as-usual" emissions (RCP 8.5) will result in annual wave overtopping on Funafuti Atoll by 2030, with overtopping at high tide under mean wave conditions occurring from 2090. Comparatively, vertical reef accretion in response to SLR will prevent any significant increase in shoreline wave energy and mitigate wave driven flooding volume by 72%. Our results provide the first quantitative assessment of how effective future reef accretion can be at mitigating SLR-associated flooding on atoll islands and endorse active reef conservation and restoration for future coastal protection.

  16. Peregrine falcon predation of endangered Laysan teal and Laysan Finches on remote Hawaiian atolls

    Science.gov (United States)

    Reynolds, Michelle H.; Nash, Sarah A.B.; Courtot, Karen

    2015-01-01

    We report the first records of Peregrine falcon (Falco peregrinus) predation on endangered Laysan teal (or duck; Anas laysanensis) and predation on endangered Laysan finches (Telespiza cantans). At Midway Atoll, vagrant Peregrine falcons killed ≥4% of a newly translocated Laysan teal population in 2006 and ≥2% in 2008. On Laysan Island during 2008–2009, remains of >76 Laysan finches (<1% of the population) were found at peregrine perches. On Midway Atoll, all depredated Laysan teal and other seabirds were recovered at kill sites on tarmac (runways). If the frequency or duration of vagrant raptors visitation increases at small atolls, this could pose a mortality risk to consider, especially during proposed translocations of endangered species. Vegetation restoration of abandoned runways near wetlands at Midway Atoll would provide cover and may help reduce mortality of endangered species due to vagrant raptors.

  17. Meteorites, atolls and whisky

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1967-06-15

    Improvements in the methods of measuring radioactive traces of elements in substances which can be hundreds of millions of years old have enabled many secrets of the remote past to be revealed. The techniques developed by nuclear scientists can also be applied to more recent times. In a symposium held in Monaco during March the discussions of radioactive dating and methods of low level counting brought references to meteorites, rocks, archaeology, coral atolls, ancient ceramics, and even whisky

  18. Formation of atoll garnets in the UHP eclogites of the Tso Morari Complex, Ladakh, Himalaya

    Science.gov (United States)

    Jonnalagadda, Mallika K.; Karmalkar, Nitin R.; Duraiswami, Raymond A.; Harshe, Shivani; Gain, Sarah; Griffin, William L.

    2017-12-01

    The eclogites of the Tso Morari Complex, Ladakh, NW Himalayas preserve both garnets with spectacular atoll textures, as well as whole porphyroblastic garnets. Whole garnets are euhedral, idiomorphic and enclose inclusions of amphibole, phengite and zoisite within the cores, and omphacite and quartz/coesite towards the rims. Detailed electron microprobe analyses and back-scattered electron images show well-preserved prograde zoning in the whole garnets with an increase in Mg and decrease in Ca and Mn contents from the core to the rim. The atoll garnets commonly consist of euhedral ring over island/peninsular core containing inclusions of phengite, omphacite and rarely amphibole between the core and ring. Compositional profiles across the studied atoll grains show elemental variations with higher concentrations of Ca and Mn with low Mg at the peninsula/island cores; contrary to this low Ca, Mn and high Mg is observed at the outer rings. Temperature estimates yield higher values at the Mg-rich atoll garnet outer rings compared to the atoll cores. Atoll garnet formation was favoured by infiltration of fluid formed due to breakdown of hydrous phases, and/or the release of structurally bounded OH from nominally anhydrous minerals at the onset of exhumation. Infiltration of fluids along pre-existing fracture pathways and along mineral inclusion boundaries triggered breakdown of the original garnet cores and released elements which were subsequently incorporated into the newly-grown garnet rings. This breakdown of garnet cores and inward re-growth at the outer ring produced the atoll structure. Calibrated geo-thermobarometers and mineral equilibria reflect that the Tso Morari eclogites attain peak pressures prior to peak temperatures representing a clockwise path of evolution.

  19. Biology of the rodents of Enewetak Atoll

    International Nuclear Information System (INIS)

    Jackson, W.B.; Vessey, S.H.; Bastian, R.K.

    1987-01-01

    Roof rats and Polynesian rats, introduced to the atoll by 20th Century commerce and the Micronesians, respectively, were present allopatrically on the larger islets. Of necessity, they were largely vegetarians. Reproductive cycles were keyed to rainfall patterns. High density populations had high stress indices, including high parasite loads. The rats, at the top of the terrestrial food pyramid, constituted a bioenvironmental monitor that was rarely utilized during the several test programs. Bioconcentration of radioisotopes, especially 137 Cs and 60 Co, occurred; rats implanted with dosimeters were determined to function as environmental radiation monitors. They hypothesized that roof rats on Enjebi survived the nearby nuclear detonation. Analysis of plasma transferrins indicated greater heterozygosity in the northern atoll rat populations. The incidence of oral palatal ridge deformations also was positively correlated with environmental radiation levels, but other gross indications of radiation effect were not found

  20. Shoreline changes in reef islands of the Central Pacific: Takapoto Atoll, Northern Tuamotu, French Polynesia

    Science.gov (United States)

    Duvat, Virginie K. E.; Pillet, Valentin

    2017-04-01

    Atoll reef islands are considered highly vulnerable to the impacts of climate change. While accelerated sea-level rise is expected to destabilize reef islands, ocean warming and acidification are considered as major threats to coral reef growth, which is of primary importance for the persistence of islands and of food supply to islanders. Using multi-date aerial imagery, shoreline and island changes between 1969 and 2013 were assessed on Takapoto Atoll, Northern Tuamotu region, in French Polynesia. Results show that over the 44-year study period, 41% of islands were stable in area while 33% expanded and 26% contracted. Island expansion was the dominant mode of change on the leeward side of the atoll. Tropical Cyclone Orama (category 3, 1983) contributed to shoreline and island change on the windward side of the atoll through the reworking of previous storm deposits and the injection of fresh sediments in the island system (with up to 62% of an island's land area being covered with fresh sediments). Human activities contributed significantly to shoreline and island change throughout the atoll through infrastructure construction, the removal of the indigenous vegetation from a number of islets and sediment mining.

  1. Radiological survey of plants, animals, and soil at five atolls in the Marshall Islands; September--October 1976

    International Nuclear Information System (INIS)

    Nelson, V.A.

    1979-01-01

    The Division of Operational Safety's portion of the Pacific Radioecology Program began in 1974 and it is a continuing program to determine the kinds and amounts of radionuclides distributed in the foods, plants, animals, and soils of the Central Pacific, especially the Marshall Islands. As part of this program, Wotje, Ailuk, Utirik, Rongelap, and Bikini tolls were visited in 1976 and samples collected. Results of the radiometric analyses of the samples are presented. Results of these analyses indicate that 90 Sr and 137 Cs are predominant in the terrestrial environment and, in addition, 241 Am and 239 240 Pu are also important in the soil from Rongelap and Bikini Atols. Naturally occurring 40 K is the predominant radionuclide in marine organisms, while 60 Co is significant in the tridacnid clams. Amounts of radioactivity vary with distance from the Bikini test site and in relation to the fallout pattern from the March 1954 Bravo test. Thus, samples from Bikini Atol had the greatest amounts of radioactivity while the northern islands of Rongelap had slightly lower amounts. The southern islands of Rongelap Atoll and Utirik Atoll had intermediate amounts of radioactivity while Ailuk and Wotje atolls had the least radioactivity of the atolls visited

  2. Population dynamics of Siderastrea stellata Verrill, 1868 from Rocas Atoll, RN: implications for predicted climate change impacts at the only South Atlantic atoll

    Directory of Open Access Journals (Sweden)

    BARBARA R. PINHEIRO

    Full Text Available ABSTRACT Coral reefs are one of the most vulnerable ecosystems to ocean warming and acidification, and it is important to determine the role of reef building species in this environment in order to obtain insight into their susceptibility to expected impacts of global changes. Aspects of the life history of a coral population, such as reproduction, growth and size-frequency can contribute to the production of models that are used to estimate impacts and potential recovery of the population, acting as a powerful tool for the conservation and management of those ecosystems. Here, we present the first evidence of Siderastrea stellata planulation, its early growth, population size-frequency distribution and growth rate of adult colonies in Rocas Atoll. Our results, together with the environmental protection policies and the absence of anthropogenic pressures, suggest that S. stellata population may have a good potential in the maintenance and recovery in the atoll. However, our results also indicate an impact on corals' recruitment, probably as a consequence of the positive temperature anomaly that occurred in 2010. Thus, despite the pristine status of Rocas Atoll, the preservation of its coral community seems to be threatened by current global changes, such as more frequent thermal stress events.

  3. Population dynamics of Siderastrea stellata Verrill, 1868 from Rocas Atoll, RN: implications for predicted climate change impacts at the only South Atlantic atoll.

    Science.gov (United States)

    Miranda, Andrea L; Cordeiro, Soraia M; Reis, Joice N; Cardoso, Lucas G; Guimarães, Alaíse G

    2017-01-01

    Coral reefs are one of the most vulnerable ecosystems to ocean warming and acidification, and it is important to determine the role of reef building species in this environment in order to obtain insight into their susceptibility to expected impacts of global changes. Aspects of the life history of a coral population, such as reproduction, growth and size-frequency can contribute to the production of models that are used to estimate impacts and potential recovery of the population, acting as a powerful tool for the conservation and management of those ecosystems. Here, we present the first evidence of Siderastrea stellata planulation, its early growth, population size-frequency distribution and growth rate of adult colonies in Rocas Atoll. Our results, together with the environmental protection policies and the absence of anthropogenic pressures, suggest that S. stellata population may have a good potential in the maintenance and recovery in the atoll. However, our results also indicate an impact on corals' recruitment, probably as a consequence of the positive temperature anomaly that occurred in 2010. Thus, despite the pristine status of Rocas Atoll, the preservation of its coral community seems to be threatened by current global changes, such as more frequent thermal stress events.

  4. 2006 Reson 8101ER Multibeam Sonar Data from Cruise AHI-06-09 - Kure Atoll, Pearl and Hermes Atoll and Kauai Island

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Reson 8101ER multibeam Data were collected from 23 June to 19 July 2006 aboard NOAA Survey Launch Acoustic Habitat Investigator (AHI) at Kure Atoll, Pearl and Hermes...

  5. Geohydrology of Enewetak Atoll islands and reefs

    International Nuclear Information System (INIS)

    Buddemeier, R.W.

    1981-01-01

    Extensive tidal studies in island wells and the lagoon at Enewetak Atoll have shown that island ground water dynamics are controlled by a layered aquifer system. The surface aquifer of unconsolidated Holocene material extends to a depth of approximately 15 m, and has a hydraulic conductivity K = 60 m/day. From 15 to 60 m (approximate lagoon depth) the reef structure consists of successive layers of altered Pleistocene materials, with bulk permeability substantially higher than that of the surface aquifer. Because of wave set-up over the windward reef and the limited pass area for outflow at the south end of the atoll, lagoon tides rise in phase with the ocean tides but fall later than the ocean water level. This results in a net lagoon-to-ocean head which can act as the driving force for outflow through the permeable Pleistocene aquifer. This model suggests that fresh water, nutrients or radioactive contaminants found in island ground water or reef interstitial water may be discharged primarily into the ocean rather than the lagoon. Atoll island fresh water resources are controlled by recharge, seawater dilution due to vertical tidal mixing between the surface and deeper aquifers, and by loss due to entrainment by the outflowing water in the deeper aquifers. Estimated lagoon-ot-ocean transit times through the deep aquifer are on the order of a few years, which corresponds well to the freshwater residence time estimates based on inventory and recharge. Islands in close proximity to reef channels have more fresh ground water than others, which is consistent with a locally reduced hydraulic gradient and slower flow through the Pleistocene aquifers

  6. Modelling detrital coral grain-size and age: Insights from sediment abrasion process of Yongle Atoll of South China Sea

    Science.gov (United States)

    Li, Y.; Zou, X.; Ge, C.; Tan, M.; Wang, C.

    2017-12-01

    Reef islands situated on the rims of atolls are composed almost exclusively of bioclastic materials locally supplied from adjacent coral reefs. Major skeletal component of these islands include coral, coralline algae, mollusks and foraminifera, produced in adjacent reefs. As the island builder, the bioclastic material is the sedimentary products, which also is the point of penetration to decipher the process. The bioclast of coral islands decrease in size with the transportation process. The grain-size provides a proxy record for the abrasion history of the unconsolidated sediment. The 230Th age of coral record the abrasion time. We hereby present a model to calculate the abrasion rate based on the data of 230Th age and grain-size of Yongle Atoll of Xisha Island, South China Sea. The grain size pattern in Yongle Atoll environment have confirm that the coral article diminution behave exponentially. The sediment composition of Yongle Atoll is identified, coral is dominant sediment constituent and the Th230 age is shown to exert an age distribution characteristics of coral detritus. We illustrate this approach by calculate the coral debris age of Xude Atoll, which located near the Yongle Atoll and then by comparing actual measured age and calculated age and to explore the dependence of the model. Observed 230 Th ages are well matched by predicted ages for medium age sediment. A poorer match for young and old sediment may result from some combination of large analytical uncertainties in the detrital ages and inhomogeneous erosion rates within the atoll. Such mismatches emphasize the need for more accurate kinematic models and for sampling strategies that are adapted to atoll-specific geologic and geomorphic conditions. Results presented constitute important new insights into regional sediment abrasion processed and on the evolution of coral atoll islands.

  7. Collection and processing of plant, animal and soil samples from Bikini, Enewetak and Rongelap Atolls

    Energy Technology Data Exchange (ETDEWEB)

    Stuart, M.L.

    1995-09-01

    The United States used the Marshall Islands for its nuclear weapons program testing site from 1946 to 1958. The BRAVO test was detonated at Bikini Atoll on March 1, 1954. Due to shifting wind conditions at the time of the nuclear detonation, many of the surrounding Atolls became contaminated with fallout (radionuclides carried by the wind currents). Lawrence Livermore National Laboratory`s (LLNL) Marshall Islands Project has been responsible for the collecting, processing, and analyzing of food crops, vegetation, soil, water, animals, and marine species to characterize the radionuclides in the environment, and to estimate dose at atolls that may have been contaminated. Tropical agriculture experiments reducing the uptake of {sup 137}Cs have been conducted on Bikini Atoll. The Marshall Islands field team and laboratory processing team play an important role in the overall scheme of the Marshall Islands Dose Assessment and Radioecology Project. This report gives a general description of the Marshall Islands field sampling and laboratory processing procedures currently used by our staff.

  8. Collection and processing of plant, animal and soil samples from Bikini, Enewetak and Rongelap Atolls

    International Nuclear Information System (INIS)

    Stuart, M.L.

    1995-09-01

    The United States used the Marshall Islands for its nuclear weapons program testing site from 1946 to 1958. The BRAVO test was detonated at Bikini Atoll on March 1, 1954. Due to shifting wind conditions at the time of the nuclear detonation, many of the surrounding Atolls became contaminated with fallout (radionuclides carried by the wind currents). Lawrence Livermore National Laboratory's (LLNL) Marshall Islands Project has been responsible for the collecting, processing, and analyzing of food crops, vegetation, soil, water, animals, and marine species to characterize the radionuclides in the environment, and to estimate dose at atolls that may have been contaminated. Tropical agriculture experiments reducing the uptake of 137 Cs have been conducted on Bikini Atoll. The Marshall Islands field team and laboratory processing team play an important role in the overall scheme of the Marshall Islands Dose Assessment and Radioecology Project. This report gives a general description of the Marshall Islands field sampling and laboratory processing procedures currently used by our staff

  9. Causes of mortality of albatross chicks at Midway Atoll

    Science.gov (United States)

    Sileo, L.; Sievert, P.R.; Samuel, M.D.

    1990-01-01

    As part of an investigation of the effect of plastic ingestion on seabirds in Hawaii, we necropsied the carcasses of 137 Laysan albatross (Diomedea immutabilis) chicks from Midway Atoll in the Pacific Ocean during the summer of 1987. Selected tissues were collected for microbiological, parasitological, toxicological or histopathological examinations. Dehydration was the most common cause of death. Lead poisoning, trauma, emaciation (starvation) and trombidiosis were other causes of death; nonfatal nocardiosis and avian pox also were present. There was no evidence that ingested plastic caused mechanical lesions or mortality in 1987, but most of the chicks had considerably less plastic in them than chicks from earlier years. Human activity (lead poisoning and vehicular trauma) caused mortality at Midway Atoll and represented additive mortality for pre-fledgling albatrosses.

  10. Transuranics in bone of deceased former residents of Rongelap Atoll, Marshall Islands

    International Nuclear Information System (INIS)

    Franke, B.; Schupfner, R.; Schuettelkopf, H.; Spennemann, D.H.R.

    1995-01-01

    Rongelap Atoll received intensive fallout from the 1 March 1954 Bravo thermonuclear test 105 miles upwind at Bikini. Fearful of their continued exposure to radiation, the residences of Rongelap Atoll went into voluntary exile in 1985. Transuranic soil concentrations on Rongelap Island are about 2-3 orders of magnitude greater than the average for the Northern hemisphere; the three dominating transuranic are 239,240 Pu and 241 Am. Only conflicting information has been available about the extent of transuranic uptake by the Rongelap community. As part of the Rongelap Resettlement Project, the community endorsed the exhumation of bones of deceased former atoll residents to provide an independent estimate of plutonium intake. This approach has the advantage of reducing the uncertainties associated with pathway modeling and the interpretation of urine data. Six graves (4 adults, 2 children) were selected for exhumation. Femora and tibiae were selected as well as humeri from the children's graves. The rest of the remains were left undisturbed. The results of the analysis of 239,240 Pu and 241 Am are presented. Assuming that the data can be considered as representative for the Rongelap population as a whole, the contamination with transuranics on Rongelap Atoll appears to result in radiation exposures in the order of 1% of the compliance limit of 100 mrem (1 mSv) effective dose equivalent per year. (author)

  11. Transuranics in bone of deceased former residents of Rongelap Atoll, Marshall Islands

    Energy Technology Data Exchange (ETDEWEB)

    Franke, B. [Institute for Energy and Environmental Research, Takoma Park, MD (United States)]|[Institut fuer Energie- und Umweltforschung e.V., Heidelberg (Germany); Schupfner, R.; Schuettelkopf, H. [Regensburg Univ. (Germany). Lab. for Environmental Radioactivity; Spennemann, D.H.R. [Charles Sturt Univ., Albury (Australia). School of Environmental and Information Sciences

    1995-11-01

    Rongelap Atoll received intensive fallout from the 1 March 1954 Bravo thermonuclear test 105 miles upwind at Bikini. Fearful of their continued exposure to radiation, the residences of Rongelap Atoll went into voluntary exile in 1985. Transuranic soil concentrations on Rongelap Island are about 2-3 orders of magnitude greater than the average for the Northern hemisphere; the three dominating transuranic are {sup 239,240}Pu and {sup 241}Am. Only conflicting information has been available about the extent of transuranic uptake by the Rongelap community. As part of the Rongelap Resettlement Project, the community endorsed the exhumation of bones of deceased former atoll residents to provide an independent estimate of plutonium intake. This approach has the advantage of reducing the uncertainties associated with pathway modeling and the interpretation of urine data. Six graves (4 adults, 2 children) were selected for exhumation. Femora and tibiae were selected as well as humeri from the children`s graves. The rest of the remains were left undisturbed. The results of the analysis of {sup 239,240}Pu and {sup 241}Am are presented. Assuming that the data can be considered as representative for the Rongelap population as a whole, the contamination with transuranics on Rongelap Atoll appears to result in radiation exposures in the order of 1% of the compliance limit of 100 mrem (1 mSv) effective dose equivalent per year. (author).

  12. Transuranics in bone of deceased former residents of Rongelap Atoll, Marshall Islands.

    Science.gov (United States)

    Franke, B; Schupfner, R; Schüttelkopf, H; Spennemann, D H

    1995-11-01

    Rongelap Atoll received intensive fallout from the 1 March 1954 Bravo thermonuclear test 105 miles upwind at Bikini. Fearful of their continued exposure to radiation, the residents of Rongelap Atoll went into voluntary exile in 1985. Transuranic soil concentrations on Rongelap Island are about 2-3 orders of magnitude greater than the average for the Northern hemisphere; the three dominating transuranics are 239,240Pu and 241Am. Only conflicting information has been available about the extent of transuranic uptake by the Rongelap community. As part of the Rongelap Resettlement Project, the community endorsed the exhumation of bones of deceased former atoll residents to provide an independent estimate of plutonium intake. This approach has the advantage of reducing the uncertainties associated with pathway modeling and the interpretation of urine data. Six graves (4 adults, 2 children) were selected for exhumation. Femora and tibiae were selected as well as humeri from the children's graves. The rest of the remains was left undisturbed. The results of the analysis of 239,240Pu and 241Am are presented. Assuming that the data can be considered as representative for the Rongelap population as a whole, the contamination with transuranics on Rongelap Atoll appears to result in radiation exposures in the order of 1% of the compliance limit of 100 mrem (1 mSv) effective dose equivalent per year.

  13. Radiological survey of plants, animals, and soil at Christmas Island and seven atolls in the Marshall Islands. Progress report for 1974--1975

    International Nuclear Information System (INIS)

    Nelson, V.A.

    1977-01-01

    The Division of Operational Safety or DOS (now Safety Standards and Compliance) portion of the Laboratory of Radiation Ecology (LRE) Pacific Radiocology Program (formerly Johnston Atoll Program) began on 1 July 1974 and is continuing. The purpose of this program is to determine the kinds and amounts of radionuclides distributed in the foods, plants, animals, and soil of the Central Pacific, especially the Marshall Islands. Five field trips were conducted for this program between April 1974 and August 1975, and about 600 samples were collected. Results of the analyses indicate that 90 Sr and 137 Cs are dominant in the terrestrial environment and, in addition, 241 Am and /sup 239,240/Pu are also important in the soil from Bikini and Rongelap atolls. Cobalt-60 and 55 Fe are predominant in the marine environment together with naturally occurring 40 K. Amounts of radioactivity vary between atolls and between islands within an atoll in relation to the distance from the nuclear weapons test sites. Bikini atoll has the highest amounts of radioactivity, but the northern islands of Rongelap Atoll have only slightly lower amounts. Rongerik and Ailinginae atolls and the southern islands of Rongelap Atoll have similar amounts of radioactivity which are lower than Bikini by factors of 5 to 10 or more. Values at Utirik Atoll are lower still, but are higher than amounts at Wotho and Kwajalein atolls. Christmas Island in the Line Islands has the least amount of radioactivity of the areas surveyed for this report

  14. beta- and gamma-Comparative dose estimates on Eniwetok Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Crase, K.W.; Gudiksen, P.H.; Robison, W.L.

    1982-05-01

    Eniwetok Atoll is one of the Pacific atolls used for atmospheric testing of U.S. nuclear weapons. Beta dose and gamma-ray exposure measurements were made on two islands of the Eniwetok Atoll during July-August 1976 to determine the beta and low energy gamma-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a beta-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to beta- or low energy gamma-contribution. The contribution at any particular site, however, is somewhat dependent on ground cover, since a minimal amount of vegetation will reduce it significantly from that over bare soil, but thick stands of vegetation have little effect on any further reductions. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey (En73). Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the beta's or low energy gamma's, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

  15. Palmyra Atoll Quickbird II Seafloor Mosaic (1.8m)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Pamyra Atoll were created by visual interpretation of remotely sensed imagery. The objective of this...

  16. Palmyra Atoll Quickbird II Terrestrial Mosaic (1.8m)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Pamyra Atoll were created by visual interpretation of remotely sensed imagery. The objective of this...

  17. Environmental sampling plan for Kwajalein Atoll Lagoon: 2017 Kwajalein sampling event

    Energy Technology Data Exchange (ETDEWEB)

    Hamilton, T. F. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-07-01

    Since the early 1980s, the U.S DOE Marshall Islands Program at LLNL has provided radiological monitoring of the marine and terrestrial environment at nuclear affected atolls in the northern Marshall Islands. The fundamental aim of these studies was to identify the level and distribution of key residual fallout radionuclide in the environment, improve understanding of prevalent radiation exposure pathways, and develop predictive dose assessments for resettled and resettling atoll population groups. These data and information were essential in terms of guiding the development of effective and environmentally protective remedial measures, and promoting potential actions to improve on food safety and security.

  18. Review at Bikini Atoll. Assessing radiological conditions at Bikini Atoll and the prospects for resettlement

    International Nuclear Information System (INIS)

    Stegnar, P.

    1998-01-01

    Some testing during the development of the atomic bomb was done in countries that do not have the infrastructure and expertise for evaluating any associated radiation risks. In such cases, outside expertise is needed to obtain independent advice about the radiological situation caused by residual radioactive material from nuclear testing. The IAEA has been requested by the governments of a number of its Member States to provide assistance in this context. Among the former nuclear test sites which the IAEA has reviewed is the Bikini Atoll of the Marshall Islands. Based on its review, the IAEA Advisory Group determined that no further corroboration of the measurements and assessments of the radiological conditions at Bikini Atoll is necessary. The data that have been collected are of sufficient quality to allow an appropriate evaluation to be performed. The limited IAEA monitoring of the area provided a good quality assurance verification of the previously collected data. It was recommended that Bikini Island should not be permanently resettled under the present radiological conditions. This recommendation was based on the assumption that persons resettling on the island would consume a diet of entirely locally produced food. The radiological data support that if a diet of this type were permitted, it could lead to an annual effective dose of about 15 mSv. This level was judged to require intervention of some type for radiation protection purposes

  19. Radiological-dose assessments of atolls in the northern Marshall Islands

    International Nuclear Information System (INIS)

    Robison, W.L.

    1983-04-01

    The Marshall Islands in the Equatorial Pacific, specifically Enewetak and Bikini Atolls, were the site of US nuclear testing from 1946 through 1958. In 1978, the Northern Marshall Islands Radiological Survey was conducted to evaluate the radiological conditions of two islands and ten atolls downwind of the proving grounds. The survey included aerial external gamma measurements and collection of soil, terrestrial, and marine samples for radionuclide analysis to determine the radiological dose from all exposure pathways. The methods and models used to estimate doses to a population in an environment where natural processes have acted on the source-term radionuclides for nearly 30 y, data bases developed for the models, and results of the radiological dose analyses are described

  20. Coastal groundwater exchange on a small Pacific atoll island: Roi Namur, Republic of the Marshall Islands

    Science.gov (United States)

    Oberle, Ferdinand K. J.; Swarzenski, Peter W.; Storlazzi, Curt

    2017-04-01

    Atoll islands, most of which only average 1-2 meters above today's sea level, provide a tremendous natural laboratory in which to study and better understand the intensifying impacts of high rates of sea-level rise on tropical reef-lined islands globally due to their unique geologic structure and limited water supply. Groundwater resources of atolls are typically minimal due to the low elevation and small surface area of the islands and are also subject to recurring droughts, and more frequent, storm-driven seawater overwash events. Although groundwater is the principal means of freshwater storage on atoll islands and is a major factor in determining the overall sustainability of island communities, hydrological data on how an aquifer will response to changes in sea-level rise or storm-driven overwash remain limited. We here present high-resolution time series hydrogeological and geochemical data to determine the role of the atoll's carbonate geology, land use, and atmospheric and oceanographic forcing in driving coastal groundwater exchange on the island of Roi Namur on Kwajalein Atoll in the Republic of the Marshall Islands. This information can provide new estimates on the recovery and resilience of coastal groundwater resources on such islands to expected climate change-driven perturbations.

  1. 76 FR 10621 - Palmyra Atoll National Wildlife Refuge, U.S. Pacific Island Territory; Nonnative Rat Eradication...

    Science.gov (United States)

    2011-02-25

    ... any of the following methods. For information on viewing or obtaining the documents, see ``Public... species in their natural setting on the Atoll. The Pacific Remote Islands Marine National Monument... eliminate black rats from Palmyra Atoll. Public Availability of the DEIS The DEIS is available for viewing...

  2. 77 FR 61426 - Rose Atoll National Wildlife Refuge, American Samoa; Draft Comprehensive Conservation Plan and...

    Science.gov (United States)

    2012-10-09

    ... DEPARTMENT OF THE INTERIOR Fish and Wildlife Service [FWS-R1-R-2012-N171; 1265-0000-10137-S3] Rose... Rose Atoll National Wildlife Refuge (NWR/refuge) for public review and comment. In the Draft CCP/EA, [email protected] . Include ``Rose Atoll National Wildlife Refuge Draft CCP/EA'' in the subject line of the...

  3. Radiation doses for Marshall Islands Atolls Affected by U.S. Nuclear Testing:All Exposure Pathways, Remedial Measures, and Environmental Loss of 137Cs

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W L; Hamilton, T F

    2009-04-20

    The United States conducted 24 nuclear tests at Bikini Atoll with a total yield of 76.8 Megatons (MT). The Castle series produced about 60% of this total and included the Bravo test that was the primary source of contamination of Bikini Island and Rongelap and Utrok Atolls. One of three aerial drops missed the atoll and the second test of the Crossroads series, the Baker test, was an underwater detonation. Of the rest, 17 were on barges on water and 3 were on platforms on an island; they produced most of the contamination of islands at the atoll. There were 42 tests conducted at Enewetak Atoll with a total yield of 31.7 MT (Simon and Robison, 1997; UNSCEAR, 2000). Of these tests, 18 were on a barge over wateror reef, 7 were surface shots, 2 aerial drops, 2 under water detonations, and 13 tower shots on either land or reef. All produced some contamination of various atoll islands. Rongelap Atoll received radioactive fallout as a result of the Bravo test on March 1, 1954 that was part of the Castle series of tests. This deposition was the result of the Bravo test producing a yield of 15 MT, about a factor of three to four greater than the predicted yield that resulted in vaporization of more coral reef and island than expected and in the debris-cloud reaching a much higher altitude than anticipated. High-altitude winds were to the east at the time of detonation and carried the debris-cloud toward Rongelap Atoll. Utrok Atoll also received fallout from the Bravo test but at much lower air and ground-level concentrations than at Rongelap atoll. Other atolls received Bravo fallout at levels below that of Utrok [other common spellings of this island and atoll (Simon, et al., 2009)]. To avoid confusion in reading other literature, this atoll and island are spelled in a variety of ways (Utrik, Utirik, Uterik or Utrok). Dose assessments for Bikini Island at Bikini Atoll (Robison et al., 1997), Enjebi Island at Enewetak Atoll (Robison et al., 1987), Rongelap Island at

  4. Resettlement of Bikini Atoll: US nuclear test site

    International Nuclear Information System (INIS)

    Robison, W.; Conrado, C.; Stuart, M.; Stoker, A.; Hamilton, T.

    1999-01-01

    Bikini Atoll was one of two sites in the Marshall Islands that were used in the 1950's by the United States for testing nuclear weapons. The testing produced widespread radioactive contamination in Bikini and much of the Northern Marshall Islands. The Bikini people, relocated in 1946 before the test program began, have long desired to return to their homeland. Coral soil on Bikini Island makes cesium-137 ( 137 Cs) much more available for plant uptake than do soils of North America and Europe. Hence, when locally grown crops mature and become available for consumption, the resulting body burden of 137 Cs and the associated doses to humans exceeds federal guidelines. The dose from the terrestrial food ingestion pathway dominates all other pathways and contributes about 90% of the total dose to returning residents. We are, therefore, involved in cost-effective efforts to reduce the dose associated with resettlement. We have evaluated several measures, in addition to soil removal, to eliminate 137 Cs from the soil and to reduce its uptake into food crops. The most effective, and the easiest to implement, is the application of potassium to the atoll soils. A dramatic reduction in 137 Cs occurs in tropical fruits after applications of potassium-rich fertilizer to experimental soil plots. This treatment reduces the associated ingestion dose to about 5% of the pre-treatment levels, and this option avoids removal of the organic-rich surface soils. In addition, the added potassium increases plant productivity. We are now focusing on determining the duration of the effects of potassium treatment on 137 Cs uptake into plants, and the rate of environmental loss of 137 Cs in the atoll ecosystem. (author)

  5. Lingering radioactivity at the Bikini and Enewetak Atolls.

    Science.gov (United States)

    Buesseler, Ken O; Charette, Matthew A; Pike, Steven M; Henderson, Paul B; Kipp, Lauren E

    2018-04-15

    We made an assessment of the levels of radionuclides in the ocean waters, seafloor and groundwater at Bikini and Enewetak Atolls where the US conducted nuclear weapons tests in the 1940's and 50's. This included the first estimates of submarine groundwater discharge (SGD) derived from radium isotopes that can be used here to calculate radionuclide fluxes in to the lagoon waters. While there is significant variability between sites and sample types, levels of plutonium ( 239,240 Pu) remain several orders of magnitude higher in lagoon seawater and sediments than what is found in rest of the world's oceans. In contrast, levels of cesium-137 ( 137 Cs) while relatively elevated in brackish groundwater are only slightly higher in the lagoon water relative to North Pacific surface waters. Of special interest was the Runit dome, a nuclear waste repository created in the 1970's within the Enewetak Atoll. Low seawater ratios of 240 Pu/ 239 Pu suggest that this area is the source of about half of the Pu in the Enewetak lagoon water column, yet radium isotopes suggest that SGD from below the dome is not a significant Pu source. SGD fluxes of Pu and Cs at Bikini were also relatively low. Thus radioactivity associated with seafloor sediments remains the largest source and long term repository for radioactive contamination. Overall, Bikini and Enewetak Atolls are an ongoing source of Pu and Cs to the North Pacific, but at annual rates that are orders of magnitude smaller than delivered via close-in fallout to the same area. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  6. 3 CFR 8337 - Proclamation 8337 of January 6, 2009. Establishment of the Rose Atoll Marine National Monument

    Science.gov (United States)

    2010-01-01

    ... of the Rose Atoll Marine National Monument 8337 Proclamation 8337 Presidential Documents Proclamations Proclamation 8337 of January 6, 2009 Proc. 8337 Establishment of the Rose Atoll Marine National... 130 nautical miles east-southeast of Pago Pago Harbor, American Samoa, lies Rose Atoll—the easternmost...

  7. The northernmost coral frontier of the Maldives: The coral reefs of Ihavandippolu Atoll under long-term environmental change.

    Science.gov (United States)

    Tkachenko, Konstantin S

    2012-12-01

    Ihavandippolu, the northernmost atoll of the Maldives, experienced severe coral bleaching and mortality in 1998 followed by several bleaching episodes in the last decade. Coral cover in the 11 study sites surveyed in July-December of 2011 in the 3-5 m depth range varied from 1.7 to 51%. Reefs of the islands located in the center of Ihavandippolu lagoon have exhibited a very low coral recovery since 1998 and remain mostly degraded 12 years after the impact. At the same time, some reefs, especially in the inner part of the eastern ring of the atoll, demonstrate a high coral cover (>40%) with a dominance of branching Acropora that is known to be one of the coral genera that is most susceptible to thermal stress. The last severe bleaching event in 2010 resulted in high coral mortality in some sites of the atoll. Differences in coral mortality rates and proportion between "susceptible" and "resistant" taxa in study sites are apparently related to long-term adaptation and local hydrological features that can mitigate thermal impacts. Abundant herbivorous fish observed in the atoll prevent coral overgrowth by macroalgae even on degraded reefs. Despite the frequent influence of temperature anomalies and having less geomorphologic refuges for coral survivals than other larger Maldivian atolls, a major part of observed coral communities in Ihavandippolu Atoll exhibits high resilience and potential for further acclimatization to a changing environment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Reassessment of the potential radiological doses for residents resettling Enewetak Atoll

    International Nuclear Information System (INIS)

    Robison, W.L.; Phillips, W.A.; Mount, M.E.; Clegg, B.R.; Conrado, C.L.

    1980-01-01

    The purpose of this report is to refine the dose predictions, subsequent to the cleanup effort, for alternate living patterns proposed for resettlement of Enewetak Atoll. The most recent data developed from projects at Enewetak and Bikini Atolls for concentration and uptake of Cs, Sr, Pu, and Am were used in conjunction with recent dietary information and current dose models to predict annual dose rates and 30- and 50-y integral doses (dose commitments). The terrestrial food chain in the most significant exposure pathway - it contributes more than 50% of the total dose - and external gamma exposure is the second most significant pathway. Other pathways evaluated are the marine food chain, drinking water, and inhalation

  9. CRED REA Algal Assessments, Johnston Atoll 2004 (NODC Accession 0010352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 12 sites at Johnston Atoll in...

  10. Monogenea of fishes from the lagoon flats of Palmyra Atoll in the Central Pacific

    Directory of Open Access Journals (Sweden)

    Victor Manuel Vidal-Martinez

    2017-11-01

    Full Text Available A survey of the monogeneans of fishes from the lagoon flats of Palmyra Atoll detected 16 species already reported from the Indo-West Pacific faunal region. A total of 653 individual fish from 44 species were collected from the sand flats bordering the lagoon of the atoll. Eighteen species of fish were infected with monogeneans. The monogenean species recovered were: Benedenia hawaiiensis on Acanthurus xanthopterus, Chaetodon auriga, Chaetodon lunula, Mulloidichthys flavolineatus, Pseudobalistes flavimarginatus and Rhinecanthus aculeatus; Ancyrocephalus ornatus on Arothron hispidus; Euryhaliotrema annulocirrus on Chaetodon auriga and Chaetodon lunula; Euryhaliotrema chrysotaeniae on Lutjanus fulvus; Euryhaliotrema grandis on Chaetodon auriga and Chaetodon lunula; Haliotrema acanthuri on Acanthurus triostegus; Haliotrema aurigae on Chaetodon auriga and Chaetodon lunula; Haliotrema dempsteri on Acanthurus xanthopterus; Haliotrema minutospirale on Mulloidichthys flavolineatus; Haliotrematoides patellacirrus on Lutjanus monostigma; Neohaliotrema bombini on Abudefduf septemfasciatus and Abudefduf sordidus; Acleotrema girellae and Acleotrema parastromatei on Kyphosus cinerascens; Cemocotylella elongata on Caranx ignobilis, Caranx melampygus and Caranx papuensis; Metamicrocotyla macracantha on Crenimugil crenilabris; and Pseudopterinotrema albulae on Albula glossodonta. All these monogenean–host combinations represent new geographical records. The monogenean species composition of the Palmyra Atoll is similar to that of the Hawaiian Islands. However, the number of species recovered was lower compared with other localities within the Indo-West Pacific, perhaps due to the geographical isolation of Palmyra Atoll.

  11. Composition, distribution and risk assessment of organochlorine pesticides in soils from the Midway Atoll, North Pacific Ocean

    Energy Technology Data Exchange (ETDEWEB)

    Ge, Jing [Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074 (China); Woodward, Lee Ann [U.S. Fish and Wildlife Service, Pacific Reefs NWRC, Honolulu, HI 96850 (United States); Li, Qing X., E-mail: qingl@hawaii.edu [Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822 (United States); Wang, Jun, E-mail: wangjun@wbgcas.cn [Key Laboratory of Aquatic Botany and Watershed Ecology, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan 430074 (China); Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822 (United States)

    2013-05-01

    Concentrations of legacy organochlorine pesticides (OCPs), including dichlorodiphenyltrichloroethane (DDT) and its metabolites (e.g., DDE and DDD), and hexachlorocyclohexanes (HCHs) were determined in 111 soil samples from the Midway Atoll. OCPs were found in all samples analyzed, with predominance of α-HCH, p,p′-DDD and p,p′-DDT. The total concentrations ranged from 0 to 127 ng g{sup −1} with a median concentration of 17 ng g{sup −1} for HCHs and 1.4 to 643 ng g{sup −1} with a median concentration of 168 ng g{sup −1} for DDTs. The possible degradation pathways and potential sources of DDTs and HCHs were investigated. The total concentrations of DDTs and HCHs were used to evaluate the cancer risk probabilities in humans via ingestion, dermal contact and inhalation of soil particles. Very low cancer risk was found in all soil samples caused by ΣDDTs and ΣHCHs. - Highlights: • Contamination levels of DDTs and HCHs were studied in the Midway Atoll, North Pacific Ocean. • Potential sources of DDTs and HCHs in soils of the Midway Atoll were investigated. • Possible degradation modes of o,p′-DDT in soils of the Midway Atoll were analyzed. • Cancer risks of DDTs and HCHs in soils of the Midway Atoll were assessed.

  12. Marshall Islands Fringing Reef and Atoll Lagoon Observations of the Tohoku Tsunami

    Science.gov (United States)

    Ford, Murray; Becker, Janet M.; Merrifield, Mark A.; Song, Y. Tony

    2014-12-01

    The magnitude 9.0 Tohoku earthquake on 11 March 2011 generated a tsunami which caused significant impacts throughout the Pacific Ocean. A description of the tsunami within the lagoons and on the surrounding fringing reefs of two mid-ocean atoll islands is presented using bottom pressure observations from the Majuro and Kwajalein atolls in the Marshall Islands, supplemented by tide gauge data in the lagoons and by numerical model simulations in the deep ocean. Although the initial wave arrival was not captured by the pressure sensors, subsequent oscillations on the reef face resemble the deep ocean tsunami signal simulated by two numerical models, suggesting that the tsunami amplitudes over the atoll outer reefs are similar to that in deep water. In contrast, tsunami oscillations in the lagoon are more energetic and long lasting than observed on the reefs or modelled in the deep ocean. The tsunami energy in the Majuro lagoon exhibits persistent peaks in the 30 and 60 min period bands that suggest the excitation of closed and open basin normal modes, while energy in the Kwajalein lagoon spans a broader range of frequencies with weaker, multiple peaks than observed at Majuro, which may be associated with the tsunami behavior within the more irregular geometry of the Kwajalein lagoon. The propagation of the tsunami across the reef flats is shown to be tidally dependent, with amplitudes increasing/decreasing shoreward at high/low tide. The impact of the tsunami on the Marshall Islands was reduced due to the coincidence of peak wave amplitudes with low tide; however, the observed wave amplitudes, particularly in the atoll lagoon, would have led to inundation at different tidal phases.

  13. CRED REA Algal Assessments, Palmyra Atoll 2004 (NODC Accession 0010352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 8 sites at Palmyra Atoll in the US...

  14. One-meter topobathymetric digital elevation model for Majuro Atoll, Republic of the Marshall Islands, 1944 to 2016

    Science.gov (United States)

    Palaseanu-Lovejoy, Monica; Poppenga, Sandra K.; Danielson, Jeffrey J.; Tyler, Dean J.; Gesch, Dean B.; Kottermair, Maria; Jalandoni, Andrea; Carlson, Edward; Thatcher, Cindy A.; Barbee, Matthew M.

    2018-03-30

    Atoll and island coastal communities are highly exposed to sea-level rise, tsunamis, storm surges, rogue waves, king tides, and the occasional combination of multiple factors, such as high regional sea levels, extreme high local tides, and unusually strong wave set-up. The elevation of most of these atolls averages just under 3 meters (m), with many areas roughly at sea level. The lack of high-resolution topographic data has been identified as a critical data gap for hazard vulnerability and adaptation efforts and for high-resolution inundation modeling for atoll nations. Modern topographic survey equipment and airborne lidar surveys can be very difficult and costly to deploy. Therefore, unmanned aircraft systems (UAS) were investigated for collecting overlapping imagery to generate topographic digital elevation models (DEMs). Medium- and high-resolution satellite imagery (Landsat 8 and WorldView-3) was investigated to derive nearshore bathymetry.The Republic of the Marshall Islands is associated with the United States through a Compact of Free Association, and Majuro Atoll is home to the capital city of Majuro and the largest population of the Republic of the Marshall Islands. The only elevation datasets currently available for the entire Majuro Atoll are the Shuttle Radar Topography Mission and the Advanced Spaceborne Thermal Emission and Reflection Radiometer Global Digital Elevation Model Version 2 elevation data, which have a 30-m grid-cell spacing and a 8-m vertical root mean square error (RMSE). Both these datasets have inadequate spatial resolution and vertical accuracy for inundation modeling.The final topobathymetric DEM (TBDEM) developed for Majuro Atoll is derived from various data sources including charts, soundings, acoustic sonar, and UAS and satellite imagery spanning over 70 years of data collection (1944 to 2016) on different sections of the atoll. The RMSE of the TBDEM over the land area is 0.197 m using over 70,000 Global Navigation Satellite

  15. Population pressure on coral atolls: trends and approaching limits.

    Science.gov (United States)

    Rapaport, M

    1990-09-01

    Trends and approaching limits of population pressure on coral atolls is discussed by examining the atoll environment in terms of the physical geography, the production systems, and resource distribution. Atoll populations are grouped as dependent and independent, and demographic trends in population growth, migraiton, urbanization, and political dependency are reviewed. Examination of the carrying capacity includes a dynamic model, the influences of the West, and philopsophical considerations. The carrying capacity is the "maximal population supportable in a given area". Traditional models are criticized because of a lack in accounting for external linkages. The proposed model is dynamic and considers perceived needs and overseas linkages. It also explains regional disparities in population distribution, and provides a continuing model for population movement from outer islands to district centers and mainland areas. Because of increased expectations and perceived needs, there is a lower carrying capacity for outlying areas, and expanded capacity in district centers. This leads to urbanization, emigration, and carrying capacity overshot in regional and mainland areas. Policy intervention is necessary at the regional and island community level. Atolls, which are islands surrounding deep lagoons, exist in archipelagoes across the oceans, and are rich in aquatic life. The balance in this small land area with a vulnerable ecosystem may be easily disturbed by scarce water supplies, barren soils, rising sea levels in the future, hurricanes, and tsunamis. Traditionally, fisheries and horticulture (pit-taro, coconuts, and breadfruit) have sustained populations, but modern influences such as blasting, reef mining, new industrial technologies, population pressure, and urbanization threaten the balance. Population pressure, which has lead to pollution, epidemics, malnutrition, crime, social disintegration, and foreign dependence, is evidenced in the areas of Tuvalu, Kiribati

  16. Dongsha Atoll: A potential thermal refuge for reef-building corals in the South China Sea.

    Science.gov (United States)

    Tkachenko, Konstantin S; Soong, Keryea

    2017-06-01

    Dongsha Atoll (also known as the Pratas Islands), the northernmost atoll in the South China Sea, experiences two contrasting physical phenomena: repetitive anomalies of the sea surface temperature exceeding the coral bleaching threshold and regular effects of the world's strongest internal waves resulting in the rhythmic upwelling of cold deep waters at the outer reef slopes of the atoll. This unique combination may result in significant differences in coral species composition and structure between the lagoon and forereef. Surveys conducted in August-September 2016 at 12 study sites in the 2-15 m depth range at Dongsha Atoll revealed a clear spatial separation between 'thermally-susceptible' stony coral genera, including Acropora, Pocillopora and Montipora, which mainly inhabited the forereef, and 'thermally-resistant' genera, including massive Porites, foliaceous Echinopora, Pavona and Turbinaria, which mainly resided in the lagoon. The mean coral cover and species richness on the forereef were respectively 1.8 and 1.4 times higher than those in the lagoon (61.3% and 98 species on the forereef vs. 34.2% and 69 species in the lagoon). Coral mortality rates, expressed as the ratio of dead to live stony corals, showed the same pattern (0.4 in the lagoon vs. 0.009 on the forereef). Furthermore, in a laboratory experiment, 'thermally-susceptible' taxa from the lagoon, (e.g. Pocillopora verrucosa and P. damicornis), exhibited higher resistance to bleaching than did their counterparts from the forereef. The present findings indicate that Dongsha Atoll is a potential thermal refuge for reef-building corals in the northern South China Sea and reveal the development of resilience and resistance to bleaching in coral communities of the lagoon. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Marine macrophytes of Minicoy (Lakshadweep) coral atoll of the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Untawale, A.G.; Jagtap, T.G.

    Thirty-seven species of marine algae, belonging to 31 genera 5 seagrass species and one mangrove species, were recorded from Minicoy Atoll. The predominant seaweeds observed were Enteromorpha clathrata, Caulerpa species, Ulva lactuca, Halimeda...

  18. Audit Report. Johnston Atoll Chemical Agent Disposal System Preparation for Year 2000

    National Research Council Canada - National Science Library

    1998-01-01

    .... The overall audit objective was to determine whether the Johnston Atoll Chemical Agent Disposal System was adequately preparing its information technology systems to resolve date-processing issues...

  19. Relationships between benthic cover, current strength, herbivory, and a fisheries closure in Glovers Reef Atoll, Belize

    Science.gov (United States)

    McClanahan, T.; Karnauskas, M.

    2011-03-01

    Benthic cover, current strengths, and fish abundance and diversity were examined on 150 lagoonal patch reefs and mapped to determine their distribution, inter-relationships, and relationship to the fisheries closure in Glovers Reef Atoll. Current strength was highest at both the northern and southern ends of the atoll and largely controlled by local wind and weakly by tidal forcing. Benthic functional group distributions varied throughout the atoll and had distinct areas of dominance. In contrast, dominance of coral species was weaker, reflecting the lost cover and zonation of Acropora, Porites, and Montastraea that were reported in the 1970s. Hard and soft corals dominated the windward rim, while the central and leeward lagoon had lower current strengths and sea grass and fleshy green algae were relatively more abundant. Brown erect algae were relatively more common in the north and calcifying green and red algae the southern ends of the atoll. Only Montastraea- Agaricia agaricites distributions were similar to reports from the 1970s with high relative dominance in the southern and northeast atoll. The central-northern zone, which was described as an Acropora zone in the 1970s, was not recognizable, and Porites porites, P. astreoides, Millepora alcicornis, and Favia fragum were the most abundant species during this survey . Hard and soft coral cover abundance declined away from the reef rim and tidal channels and was associated with fast seawater turnover and high surgeonfish abundance. Consequently, the windward rim area has retained the most original and persistent hard-soft coral and surgeonfish community and is considered a priority for future management, if the goal is to protect coral from fishing impacts.

  20. CRED REA Fish Team Belt Transect Survey at Swains Atoll, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 8 sites at Swains Atoll in...

  1. CRED REA Coral Population Parameters at Palmyra Atoll, Line Islands, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Palmyra Atoll in the...

  2. CRED REA Coral Population Parameters at Rose Atoll, American Samoa, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at Rose Atoll in American...

  3. CRED REA Fish Team Belt Transect Surveys at Kure Atoll 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 3 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in October,...

  4. Radiation doses for Marshall Islands Atolls affected by U.S. nuclear testing: all exposure pathways, remedial measures, and environmental loss of (137)Cs.

    Science.gov (United States)

    Robison, William L; Hamilton, Terry F

    2010-01-01

    Radiation doses calculated for people resettling Bikini Island at Bikini Atoll, Enjebi Island at Enewetak Atoll, Rongelap Island at Rongelap Atoll, and Utrōk Island at Utrōk Atoll are presented. Residence is assumed to begin in 2010. In previous dose assessments it was shown that (137)Cs accounts for about 98% of the total dose for returning residents. About 85 to 90% (depending on the atoll) is via consumption of locally grown foods containing (137)Cs, and about 10 to 15% is due to external exposure from (137)Cs in the soil. These assessments were made using only the radiological half-life of (137)Cs (30.1 y). We have shown since that there is an environmental loss of (137)Cs from soil to groundwater that results in a more rapid loss of (137)Cs from the atoll ecosystem. The mean effective half-life of (137)Cs at the atolls is 8.5 y. Moreover, treatment of coconut trees with potassium (K) reduces (137)Cs concentration in drinking coconut meat at Bikini Atoll to about 5% of pretreatment concentrations. The magnitude of reduction is dependent on the concentration of (137)Cs in soil, and thereby in food crops, and is less for Enjebi and Rongelap Islands than for Bikini Island. Treatment of food crops and fruit trees with K and removal of the top 15 cm of soil around houses and community buildings prior to construction to reduce external exposure where people spend most of their time has been presented to the communities as a "Combined Option" remediation strategy. Doses presented here are calculated using the Combined Option, effective half-life of (137)Cs at the atolls, and a diet of both imported and local foods. The average natural background dose in the Marshall Islands, plus the anthropogenic nuclear test-related dose at Bikini, Enjebi, and Rongelap Islands, is less for each of the islands than the average background dose in the U.S. and Europe.

  5. CRED REA Coral Population Paramaters at Rose Atoll, American Samoa, 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 1 or 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 11 sites at Rose Atoll in...

  6. Baseline Marine Biological Survey ROI-NAMUR Outfall United States Army Kwajalein Atoll, Republic of the Marshall Islands, 1997(NODC Accession 0000630)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Roi-Namur is located at the northernmost tip of Kwajalein Atoll, approximately 64 kilometers north of the U.S. Army Kwajalein Atoll(USAKA) central command post on...

  7. Dosimetry methods and results for the former residents of Bikini Atoll

    International Nuclear Information System (INIS)

    Greenhouse, N.A.

    1979-01-01

    The US Government utilized Bikini and Enewetak Atolls in the northern Marshall Islands of Micronesia for atomspheric tests of nuclear explosives in the 1940's and 1950's. The original inhabitants of these atolls were relocated prior to the tests. During the early 1970's, a small but growing population of Marshallese people reinhabited Bikini. Environmental and personnel radiological monitoring programs were begun in 1974 to ensure that doses and dose commitments received by Bikini residents remained within US Federal Radiation Council guidelines. Dramatic increases in 137 Cs body burdens among the inhabitants between April 1977 and 1978 may have played a significant role in the government decision to move the 140 Bikinians in residence off of the atoll in August 1978. The average 137 Cs body burden for the population was 2.3 μCi in April 1978. Several individuals, however, exceeded the maximum permissible body burden of 3 μCi, and some approached 6 μCi. The resultant total dose commitment was less than 200 mrem for the average resident. The average total dose for the mean residence interval of approx. 4.5 years was about 1 rem. The sources of exposure, the probable cause of the unexpected increase in 137 Cs body burdens, and the methods for calculating radionuclide intake and resultant doses are discussed. Suggestions are offered as to the implications of the most significant exposure pathways for the future inhabitation of Bikini and Enewetak

  8. Bikini Atoll coral biodiversity resilience five decades after nuclear testing

    International Nuclear Information System (INIS)

    Richards, Zoe T.; Beger, Maria; Pinca, Silvia; Wallace, Carden C.

    2008-01-01

    Five decades after a series of nuclear tests began, we provide evidence that 70% of the Bikini Atoll zooxanthellate coral assemblage is resilient to large-scale anthropogenic disturbance. Species composition in 2002 was assessed and compared to that seen prior to nuclear testing. A total of 183 scleractinian coral species was recorded, compared to 126 species recorded in the previous study (excluding synonomies, 148 including synonomies). We found that 42 coral species may be locally extinct at Bikini. Fourteen of these losses may be pseudo-losses due to inconsistent taxonomy between the two studies or insufficient sampling in the second study, however 28 species appear to represent genuine losses. Of these losses, 16 species are obligate lagoonal specialists and 12 have wider habitat compatibility. Twelve species are recorded from Bikini for the first time. We suggest the highly diverse Rongelap Atoll to the east of Bikini may have contributed larval propagules to facilitate the partial resilience of coral biodiversity in the absence of additional anthropogenic threats

  9. Observations of infragravity motions for reef fringed islands and atolls

    Science.gov (United States)

    Becker, J. M.; Merrifield, M. A.; Ford, M.

    2012-12-01

    The frequency of flooding events that affect low lying islands and atolls in the Pacific is expected to increase under current sea level rise projections. Infragravity (IG) motions, with periods ranging from approximately 25 to 400 seconds, are an important component of wave driven flooding events for reef fringed islands and atolls. The IG variability during wave events is analyzed and interpreted dynamically from pressure and current observations at four cross-reef transects in the North Pacific Ocean that include sites in the Republic of the Marshall Islands and Guam. The IG motions are shown to depend upon the spectral properties of the incident wave forcing and reef flat characteristics that include reef flat length (ranging from 100m to 450m at the four sites) and total water level due to setup and tides. A small inundation event at one of the sites is shown to occur due to large shoreline infragravity energy.

  10. Baseline for beached marine debris on Sand Island, Midway Atoll

    Science.gov (United States)

    Ribic, Christine; Seba B. Sheavly,; John Klavitter,

    2012-01-01

    Baseline measurements were made of the amount and weight of beached marine debris on Sand Island, Midway Atoll, June 2008–July 2010. On 23 surveys, 32,696 total debris objects (identifiable items and pieces) were collected; total weight was 740.4 kg. Seventy-two percent of the total was pieces; 91% of the pieces were made of plastic materials. Pieces were composed primarily of polyethylene and polypropylene. Identifiable items were 28% of the total; 88% of the identifiable items were in the fishing/aquaculture/shipping-related and beverage/household products-related categories. Identifiable items were lowest during April–August, while pieces were at their lowest during June–August. Sites facing the North Pacific Gyre received the most debris and proportionately more pieces. More debris tended to be found on Sand Island when the Subtropical Convergence Zone was closer to the Atoll. This information can be used for potential mitigation and to understand the impacts of large-scale events such as the 2011 Japanese tsunami.

  11. Bikini Atoll coral biodiversity resilience five decades after nuclear testing

    Energy Technology Data Exchange (ETDEWEB)

    Richards, Zoe T. [Museum of Tropical Queensland, Flinders St, Townsville, QLD 4810 (Australia) and Australian Research Council Centre of Excellence for Coral Reef Studies, James Cook University, Townsville, QLD 4811 (Australia) and School of Marine and Tropical Biology, James Cook University, Townsville QLD 4811 (Australia); NRAS - Marshall Islands: Natural Resource Assessment Surveys (Australia)], E-mail: zoe.richards@jcu.edu.au; Beger, Maria [Ecology Centre and Commonwealth Research Facility for Applied Environmental Decision Analysis, University of Queensland, St Lucia, QLD 4072 (Australia); NRAS - Marshall Islands: Natural Resource Assessment Surveys (Australia); Pinca, Silvia [College of the Marshall Islands, Majuro, Marshall Islands, NRAS - Marshall Islands: Natural Resource Assessment Surveys (Australia); Wallace, Carden C. [Museum of Tropical Queensland, Flinders St, Townsville, QLD 4810 (Australia)

    2008-03-15

    Five decades after a series of nuclear tests began, we provide evidence that 70% of the Bikini Atoll zooxanthellate coral assemblage is resilient to large-scale anthropogenic disturbance. Species composition in 2002 was assessed and compared to that seen prior to nuclear testing. A total of 183 scleractinian coral species was recorded, compared to 126 species recorded in the previous study (excluding synonomies, 148 including synonomies). We found that 42 coral species may be locally extinct at Bikini. Fourteen of these losses may be pseudo-losses due to inconsistent taxonomy between the two studies or insufficient sampling in the second study, however 28 species appear to represent genuine losses. Of these losses, 16 species are obligate lagoonal specialists and 12 have wider habitat compatibility. Twelve species are recorded from Bikini for the first time. We suggest the highly diverse Rongelap Atoll to the east of Bikini may have contributed larval propagules to facilitate the partial resilience of coral biodiversity in the absence of additional anthropogenic threats.

  12. Numerical modeling of atoll island hydrogeology.

    Science.gov (United States)

    Bailey, R T; Jenson, J W; Olsen, A E

    2009-01-01

    We implemented Ayers and Vachers' (1986) inclusive conceptual model for atoll island aquifers in a comprehensive numerical modeling study to evaluate the response of the fresh water lens to selected controlling climatic and geologic variables. Climatic factors include both constant and time-varying recharge rates, with particular attention paid to the effects of El Niño and the associated drought it brings to the western Pacific. Geologic factors include island width; hydraulic conductivity of the uppermost Holocene-age aquifer, which contains the fresh water lens; the depth to the contact with the underlying, and much more conductive, Pleistocene karst aquifer, which transmits tidal signals to the base of the lens; and the presence or absence of a semiconfining reef flat plate on the ocean side. Sensitivity analyses of steady-steady simulations show that lens thickness is most strongly sensitive to the depth to the Holocene-Pleistocene contact and to the hydraulic conductivity of the Holocene aquifer, respectively. Comparisons between modeling results and published observations of atoll island lens thicknesses suggest a hydraulic conductivity of approximately 50 m/d for leeward islands and approximately 400 m/d for windward islands. Results of transient simulations show that lens thickness fluctuations during average seasonal conditions and El Niño events are quite sensitive to island width, recharge rate, and hydraulic conductivity of the Holocene aquifer. In general, the depletion of the lens during drought conditions is most drastic for small, windward islands. Simulation results suggest that recovery from a 6-month drought requires about 1.5 years.

  13. An assessment of potential health impacts on Utrok Atoll from exposure to cesium-137 (137Cs) and plutonium

    International Nuclear Information System (INIS)

    Hamilton, T

    2007-01-01

    Residual fallout contamination from the nuclear test program in the Marshall Islands is a concern to Marshall Islanders because of the potential health risks associated with exposure to residual fallout contamination in the environment. Scientists from Lawrence Livermore National Laboratory (LLNL) have been monitoring the amount of fallout radiation delivered to Utrok Atoll residents over the past 4 years. This briefing document gives an outline of our findings from the whole body counting and plutonium bioassay monitoring programs. Additional information can be found on the Marshall Islands web site (http://eed.lnl.gov/mi/). Cesium-137 is an important radioactive isotope produced in nuclear detonations and can be taken up from coral soils into locally grown food crop products that form an important part of the Marshallese diet. The Marshall Islands whole body counting program has clearly demonstrated that the majority of Utrok Atoll residents acquire a very small but measurable quantity of cesium-137 in their bodies (Hamilton et al., 2006; Hamilton et. al., 2007a; 2007b;). During 2006, a typical resident of Utrok Atoll received about 3 mrem of radiation from internally deposited cesium-137 (Hamilton et al., 2007a). The population-average dose contribution from cesium-137 is around 2% of the total radiation dose that people normally experience from naturally occurring radiation sources in the Marshall Islands and is thousands of times lower than the level where radiation exposure is known to produce measurable health effects. The existing dose estimates from the whole body counting and plutonium bioassay programs are also well below radiological protection standards for protection of the public as prescribed by U.S. regulators and international agencies including the Marshall Islands Nuclear Claim Tribunal (NCT). Similarly, the level of internally deposited plutonium found in Utrok Atoll residents is well within the range normally expected for people living in the

  14. Statistical aspects of the cleanup of Enewetak Atoll

    International Nuclear Information System (INIS)

    Giacomini, J.J.; Miller, F.L. Jr.

    1981-01-01

    The Desert Research Institute participated in the Enewetak Atoll Radiological Cleanup by providing data-base management and statistical analysis support for the Department of Energy team. The data-base management responsibilities included both design and implementation of a system for recording (in machine-retrievable form) all radiological measurements made during the cleanup, excluding personnel dosimetry. Statistical analyses were performed throughout the cleanup and were used to guide excavation activities

  15. Report on a few Octocorals from Eniwetok Atoll, Marshall Islands

    NARCIS (Netherlands)

    Verseveldt, J.

    1972-01-01

    In 1969 Dr. Arthur G. Humes, Boston University, Massachusetts, U.S.A., collected a number of octocorals at Eniwetok Atoll, Marshall Islands. He found that most of these corals were the hosts of copepods, just like the corals collected by him in the waters north-west of Madagascar (vide Verseveldt,

  16. Phytoplankton biomass dynamics and environmental variables around the Rocas Atoll Biological Reserve, South Atlantic

    Directory of Open Access Journals (Sweden)

    Marina Cavalcanti Jales

    2015-12-01

    Full Text Available Abstract The Rocas Atoll Biological Reserve is located in the Atlantic Ocean, at 3º 51' S and 33º 49' W. It lies 143 nautical miles from the City of Natal, Rio Grande do Norte (Brazil. The purpose of this study was to analyze the hydrology, water masses, currents and chlorophyll a content to determine the dynamics of phytoplankton biomass around the Rocas Atoll. Samples were collected in July 2010 in the area around the Atoll, using the Research Vessel Cruzeiro do Sul of the Brazilian Navy. Two transects were established according to the surface currents, one of which at the southeast of the Atoll (SE and the other at norwest (NW. Three collection points were determined on each of these transects. Samples were collected at different depths (surface and DCM - Deep Chlorophyll Maximum and different times (day and night. According to PCA (Principal Component Analysis, the nutrients analyzed, DIN (dissolved inorganic nitrogen, DIP (dissolved inorganic phosphorus and silicate, were inversely correlated with temperature and dissolved oxygen. Most environmental variables showed a significant increase due to the turbulence on the Northwest transect. There was an increase in the concentration of chlorophyll a and nutrients when the temperature and oxygen in the mixed layer was reduced due to the influence of the SACW (South Atlantic Central Water. Despite the increase observed in some variables such as nutrient salts and chlorophyll a, the temperature in the mixed layer attained a mean value of 23.23 ºC due to the predominance of Tropical Water. The increase of the phytoplankton biomass on the NW transect was, therefore, caused by the "island effect" and not by upwelling.

  17. CRED Gridded Bathymetry near Midway Atoll (100-102), Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-102b is a 60-m ASCII grid of depth data collected near Midway Atoll in the Northwestern Hawaiian Islands as of May 2003. This grid has been produced as part...

  18. Environmental assessment for the resettlement of Eneu Island on Bikini Atoll, Republic of the Marshall Islands

    International Nuclear Information System (INIS)

    Maragos, J.E.; Agegian, Catherine

    1986-01-01

    This environmental assessment evaluates various alternatives to return the Bikini people to their homeland on Bikini Atoll. Eneu Island was spared the heavy nuclear contamination that rendered Bikini Island, the largest and main inhabitable island on the atoll, presently unsuitable for resettlement. The economic, social, technical and environmental consequences of all alternatives were compared, and alternative sites, purposes and scales for resettlement were included in the analysis. This environmental assessment explores these alternatives in detail and concludes that the resettlement of Eneu Island by some of the Bikini people at this time will not result in significant adverse effects to the environment nor will it foreclose any other full scale resettlement option involving the cleanup of Bikini Atoll. In addition, it concludes that the resettlement of Eneu can be accomplished independently from the planned cleanup and resettlement of Bikini Island. Plans and combination of plans involving the early resettlement of Eneu are fully feasible and implementable at this time. (author)

  19. Environmental assessment for the resettlement of Eneu Island on Bikini Atoll, Republic of the Marshall Islands

    Energy Technology Data Exchange (ETDEWEB)

    Maragos, J E [Environmental Resources Section, U.S. Army Corps of Engineers, Pacific Ocean Division, HI (United States); Agegian, Catherine [University of Hawaii, Department of Oceanography, Honolulu, HI (United States)

    1986-07-01

    This environmental assessment evaluates various alternatives to return the Bikini people to their homeland on Bikini Atoll. Eneu Island was spared the heavy nuclear contamination that rendered Bikini Island, the largest and main inhabitable island on the atoll, presently unsuitable for resettlement. The economic, social, technical and environmental consequences of all alternatives were compared, and alternative sites, purposes and scales for resettlement were included in the analysis. This environmental assessment explores these alternatives in detail and concludes that the resettlement of Eneu Island by some of the Bikini people at this time will not result in significant adverse effects to the environment nor will it foreclose any other full scale resettlement option involving the cleanup of Bikini Atoll. In addition, it concludes that the resettlement of Eneu can be accomplished independently from the planned cleanup and resettlement of Bikini Island. Plans and combination of plans involving the early resettlement of Eneu are fully feasible and implementable at this time. (author)

  20. Managing an invasive corallimorph at Palmyra Atoll National Wildlife Refuge, Line Islands, Central Pacific

    Science.gov (United States)

    Work, Thierry M.; Aeby, Greta S.; Neal, Benjamin P.; Price, Nichole N.; Conklin, Eric; Pollock, Amanda

    2018-01-01

    In 2007, a phase shift from corals to corallimorpharians (CM) centered around a shipwreck was documented at Palmyra Atoll, Line Islands. Subsequent surveys revealed CM to be overgrowing the reef benthos, including corals and coralline algae, potentially placing coral ecosystems in the atoll at risk. This prompted the U.S. Fish and Wildlife Service, the lead management agency of the atoll, to remove the shipwreck. Subsequent surveys showed reductions in CM around the ship impact site. We explain patterns of spread of the CM in terms of both life history and local currents and show with a pilot study that pulverized bleach may be an effective tool to eradicate CM on a local scale. If applied strategically, particularly in heavily infested (> 66% cover) areas, active intervention such as this could be an effective management tool to reduce CM impact on localized areas and decrease colonization rate of remaining reefs. This is the first documentation of the response of an invasive cnidarian to shipwreck removal. While this was a singular event in Palmyra, the spatial and temporal patterns of this invasion and the eradications lessons described herein, are useful for anticipating and controlling similar situations elsewhere.

  1. Ground-water resources of the Laura area, Majuro Atoll, Marshall Islands

    Science.gov (United States)

    Hamlin, S.N.; Anthony, S.S.

    1987-01-01

    The water system that supplies the heavily populated Dalap-Uliga-Darrit (DUD) area of Majuro atoll, Marshall Island, relies almost entirely upon airstrip catchment of rain water. Droughts cause severe water supply problems and water rationing is required, even during periods of normal rainfall. The Laura area contains a substantial lens of fresh groundwater that could be developed for export to the DUD area 30 mi to the east. Study of the groundwater resource at Laura involved a survey of existing wells, installation of monitoring wells and test holes, compilation of continuous records of rainfall and water level fluctuations, and collection of water quality data. Test hole data permitted the definition of three geohydrologic units which correlate well with similar units in Bikini and Enewetak atolls. The units consist of two layers of unconsolidated reef and lagoon sediments resting on a dense, highly permeable limestone. The potable water zone, or freshwater nucleus, of the lens is contained mostly within the unconsolidated layers, which are much less permeable than the basal limestone. Recharge to the Laura freshwater lens is estimated to be 1.8 mil gal/day, based on an average annual rainfall of 140 in. Sustainable yield is estimated to be about 400,000 gal/day. Shallow skimming wells or infiltration galleries similar to those used on Kwajalein atoll would be appropriate to develop the freshwater lens. The impact of development on the lens can be determined by monitoring the salinity in developed water and in a network of monitor wells. (Author 's abstract)

  2. CRED REA Coral Population Parameters at Kure Atoll, Northwestern Hawaiiian Islands, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in the...

  3. CRED REA Coral Population Parameters at Kure Atoll, Northwestern Hawaiiian Islands, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in the...

  4. CRED REA Coral Population Parameters at Midway Atoll, Northwestern Hawaiiian Islands, 2002

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Midway Atoll in the...

  5. CRED REA Coral Population Parameters at Midway Atoll, Northwestern Hawaiian Islands, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Midway Atoll in the...

  6. Origin and migration of trace elements in the surface sediments of Majuro Atoll, Marshall Islands.

    Science.gov (United States)

    Ito, Lisa; Omori, Takayuki; Yoneda, Minoru; Yamaguchi, Toru; Kobayashi, Ryuta; Takahashi, Yoshio

    2018-07-01

    The sediments of Majuro Atoll, Marshall Islands, consist of bioclastic materials, including foraminifera and coral debris. The sedimentary depth profiles of elements showed that various elements including zinc (Zn) and copper (Cu) were enriched in the upper layers of the islands of Majuro Atoll. Carbon-14 dating revealed that the sedimentation of the upper layer was completed before 1670 and 542 cal BP in Laura and Calalen, respectively. The enriched elements could be categorized by their origins: (a) terrestrial elements transported as dust (aluminum (Al) and rare earth elements (REEs)); (b) anthropogenic elements (Zn and Cu); and (c) elements supplied by seabirds (phosphorus (P)). From the results of the total amount of Al supplied to sediments for ca. 2000 years, Al in Majuro Atoll was suggested to be airborne origin. The enrichment factors of the elements normalized to Al concentration of continental crust showed that REEs were also transported as dust, while Zn and Cu were mainly of anthropogenic origin. The speciation analysis by X-ray absorption near-edge structure (XANES) showed the presence of Zn-Cu alloys originated from industrial products. It was also revealed that Zn was enriched in the surface due to anthropogenic emission after urbanization on Majuro Atoll and fixed by carbonate and phosphate at the upper layer, which inhibits migration of Zn into the deeper layer and its release to the groundwater and costal water. Hence, the fixation of heavy metals at the surface prevents their exposure to aquatic organisms and residents via fresh groundwater in the island. Copyright © 2018 Elsevier Ltd. All rights reserved.

  7. beta. and. gamma. -comparative dose estimates on Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Crase, K.W.; Gudiksen, P.H.; Robison, W.L. (California Univ., Livermore (USA). Lawrence Livermore National Lab.)

    1982-05-01

    Enewetak Atoll in the Pacific is used for atmospheric testing of U.S. nuclear weapons. Beta dose and ..gamma..-ray exposure measurements were made on two islands of the Enewetak Atoll during July-August 1976 to determine the ..beta.. and low energy ..gamma..-contribution to the total external radiation doses to the returning Marshallese. Measurements were made at numerous locations with thermoluminescent dosimeters (TLD), pressurized ionization chambers, portable NaI detectors, and thin-window pancake GM probes. Results of the TLD measurements with and without a ..beta..-attenuator indicate that approx. 29% of the total dose rate at 1 m in air is due to ..beta..- or low energy ..gamma..-contribution. The contribution at any particular site, however, is reduced by vegetation. Integral 30-yr external shallow dose estimates for future inhabitants were made and compared with external dose estimates of a previous large scale radiological survey. Integral 30-yr shallow external dose estimates are 25-50% higher than whole body estimates. Due to the low penetrating ability of the ..beta..'s or low energy ..gamma..'s, however, several remedial actions can be taken to reduce the shallow dose contribution to the total external dose.

  8. CRED REA Fish Team Stationary Point Count Surveys at Rose Atoll, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Stationary Point Counts at 4 stations at each survey site were surveyed as part of Rapid Ecological Assessments conducted at 12 sites at Rose Atoll in American Samoa...

  9. Formation of Atoll Garnets in the UHP Eclogites of the Tso Morari ...

    Indian Academy of Sciences (India)

    7

    across the studied atoll grains show elemental variations with higher concentrations of Ca and. 10 ...... from a single eclogite outcrop in the complex and probably represent a case of accidental. 28 ... Textural and compositional relations in the.

  10. CRED REA Fish Team Stationary Point Count Surveys at Midway Atoll, 2003

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Stationary Point Counts at 4 stations at each survey site were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Midway Atoll in July and...

  11. CRED REA Fish Team Stationary Point Count Surveys at Kure Atoll, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Stationary Point Counts at 4 stations at each survey site were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in October, 2004...

  12. Culture, hydrology, and other situational controls on atoll freshwater availability (Majuro, Republic of the Marshall Islands)

    Science.gov (United States)

    Shuster, W.

    2016-12-01

    The comparatively uncertain rainfall catch and rising seas in isolated North Pacific atoll communities has presented serious challenges to maintain human communities with freshwater volume. Moreover, the feudal hierarchy, which structures social and economic relationships among local governance and citizens contributes equally to problems and potential solutions. These relationships modulate the availability of critical ecosystem services generated by freshwater, with additional constraints contributed by climate change, rainfall variability (e.g., current El Niño climate pattern), and continuous threat of drought. The major freshwater resources for an atoll are the groundwater freshwater lens, residential and commercial rainwater harvesting, large-scale rainfall catchments (e.g., an airport runway), imported-virtual water, or desalinization subsidies. The significance of each of these resources scale across different atolls according to size, topography, soils, population, infrastructure, and land ownership. The potential integration and coordination of these water resources is largely unrealized due to land ownership, the lack of a contiguous catchment area, uneven and fractured governance. The situational aspects are further characterized by feuding among families and communities (some resource rich, some resource poor), and conflicting land use priorities where agriculture placement and practice can compromise the quality of already limited freshwater resources. This presentation uses the example of Majuro atoll (Republic of the Marshall Islands), field data and other observations, to illustrate sociohydrologic-drivers of freshwater availability, and suggests approaches that may improve on current and ongoing threats to public health and well-being.

  13. Effect of climate and environmental changes on plankton biodiversity and bigeochemical cycles of the Dongsha (Pratas) Atoll, South China Sea

    Science.gov (United States)

    Lo, Wen-tseng; Hsu, Pei-Kai; Hunag, Jia-Jang; Wang, Yu-Huai

    2013-04-01

    Dongsha (Pratas) Atoll, the so called "Pearl Crown of South China Sea", is a well-developed atoll with a total area of 80000 hectares. It possesses various ecosystems and has very high biodiversity, but it is very sensitive to climate change and physical processes. According to our investigation within the shallow semi-enclosed atoll in April, July, and October, 2011 (i.e., spring, summer, and autumn, respectively), we found that plankton assemblages and hydrographical conditions exhibited clear seasonal and spatial variations. Colder and higher salinity water was observed in April, while warmer water in July and lower salinity water in October, respectively. Nutrient concentration within the atoll was similar to that of the oligotrophic South China Sea waters and seemed to be in nitrogen-limit situation, while the distribution pattern of DOC and POC was mainly attributed to Chla and imported detritus matters. Carbon deposition flux also showed significant seasonal changes, but POC/PN value was near Redfield ratio, implying mostly due to biogenic factors; however it could still be classified as a typical coral ecosystem, since CaCO3 sinking flux generally was 30 times higher than that of organic matter. Plankton biodiversity was quite high in the atoll, and preformed apparent seasonal succession; in total, 82 phytoplankton species and 67 copepod species were recorded; furthermore, crab zoea (17.3% of the total zooplankton by number), fish eggs (12.5%), and shrimp larvae (4.2%), were relatively abundant in zooplankton community, revealed that atoll might be a good hatching ground. We deduced that the seasonal patterns of chemical and biological variables were mainly influenced by monsoons and precipitation, while small scales of temporal and spatial variations could be ascribed to internal wave and tide in this study area.

  14. Comparison of gamma-ray exposure rate measurements at Bikini Atoll

    International Nuclear Information System (INIS)

    Gudiksen, P.H.; Crites, T.R.

    1975-01-01

    A radiological survey of Bikini and Eneu Islands of the Bikini Atoll was conducted during June 1975 to assess the potential radiation doses that may be received by the returning Bikinians. Bikini Atoll was one of the U.S. nuclear weapons testing sites in the Pacific. An integral part of the survey included measurements of the gamma-ray exposure rates at 1 m above the ground with portable NaI instruments at nearly 2700 locations on the two islands. For comparison purposes, similar measurements were made with a pressurized ion chamber at approximately 200 locations, and with LiF and CaF 2 :Dy thermoluminescent dosimeters (TLDs) at 80 locations. The results indicate that the NaI scintillators overresponded because of their nonlinear energy characteristics. The responses of the LiF dosimeters and the pressurized ion chamber agreed to within 13 percent. Attenuation studies with LiF TLDs indicated that roughly 25 percent of the total free air exposure rate at 1 m was due to beta radiation

  15. External exposure measurements at Bikini Atoll

    International Nuclear Information System (INIS)

    Greenhouse, N.A.; Miltenberger, R.P.; Lessard, E.T.

    1979-01-01

    External exposure rate surveys from 1975 to 1977 on the islands Nam, Eneu and Bikini of Bikini Atoll gave average external exposure rates of 24, 5.7, and 32 μR/hr respectively. The exposure rate on Eneu Island is uniform, whereas those on Bikini and Nam range from 7.0 to 80. μR/hr. Based on an assumed living pattern at Bikini Island, the adult male Bikinian is estimated to be in the presence of an external radiation field corresponding to 16 μR/hr due to debris and fallout from the 1954 BRAVO incident. This corresponds to a 30 year dose equivalent of 2.8 rem

  16. Baseline marine biological survey at Roi-Namur sewage outfall, United States Army Kwajalein Atoll, Republic of the Marshall Islands, 1997 (NODC Accession 0000630)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Roi-Namur is located at the northernmost tip of Kwajalein Atoll, approximately 64 kilometers north of the U.S. Army Kwajalein Atoll (USAKA) central command post on...

  17. Long-distance dispersal of the coconut palm by migration within the coral atoll ecosystem.

    Science.gov (United States)

    Harries, Hugh C; Clement, Charles R

    2014-03-01

    The location of the original home of the coconut palm, Cocos nucifera, and the extent of its natural dispersal are not known. Proponents of a South American origin must explain why it is not indigenous there and why it shows greatest diversity in southern Asia. Conversely, proponents of an Asian origin must explain why there are no Asian Cocoseae and why the closest botanical relative to Cocos is in South America. Both hypotheses share the common problems of how, when, where and in what directions long-distance dispersal occurred. These difficulties are resolved by accepting that C. nucifera originated and dispersed by populating emerging islands of the coral atoll ecosystem, where establishment conditions impose high selection pressures for survival. When lifted by wave action onto virtually sterile, soilless coralline rocks just above sea level and exposed to the full impact of the sun, seednuts must germinate, root and establish vigorous populations. The cavity within the nut augments the buoyancy provided by the thick husk, which in turn protects the embryo and, by delaying germination, simultaneously extends viability while floating and provides a moisture-retentive rooting medium for the young seedling. These adaptations allow coconuts to disperse widely through the coral atoll ecosystem. The monthly production of fruit and the long floating duration ensure that viable seednuts are always available in the lagoon to replace those destroyed by hurricanes and tsunamis, or to populate newly emerged coral atolls elsewhere. Long-distance dispersal is secondary, because it was the spontaneous, independent migration of coral polyps on a prolonged geological time scale that generated new coral atolls in new areas where the coconuts would be amongst the earliest inhabitants. The coconut palm became an intermittent, itinerant, pioneer endemic there, and also on suitable beaches on volcanic or large islands and continental coastlines.

  18. Relationship between elemental distribution in soil and human impact in Majuro Atoll

    Science.gov (United States)

    Ito, L.; Takahashi, Y.; Yoneda, M.; Omori, T.; Yamazaki, K.; Yoshida, H.; Tamenori, Y.; Suga, H.; Yamaguchi, T.

    2015-12-01

    Majuro Atoll is one of islands of the Marshall Islands, located in the central Pacific Ocean. Reef-building corals and biological remains such as foraminifera have formed the islands under the influence of sea-level changes in the Holocene. Since the altitude of the general coral reef island tends to be very low, it is believed that the islands are vulnerable to natural disasters and climate change. However, people have lived in the Majuro Atoll in Marshall Islands for more than 2000 years. Reef islands in the same atoll are often considered to have same tendencies in the developing process; however, (i) there are possibilities that each geography produces different condition in habitat and (ii) human activities have changed the original nature in the island. In this study, we focus on the changes of physico-chemical conditions of soil depending on the depth according to time series variation in three islands in Majuro Atoll. Dating of each depth was conducted by radiocarbon (14C) measurement for foraminifera using accelerator mass spectrometry (AMS) and Bayesian age-depth Models. X-ray fluorescence (XRF) and ICP-MS analyses were employed to measure major and trace elements at different depth, respectively. Among them, phosphorus (P) is considered to play an important role in soil development; therefore X-ray absorption fine structure (XAFS) analysis was also conducted to examine the chemical form of P. Scanning electron microscope (SEM) was used to examine the elemental distribution in the soil particles, while X-ray computed tomography (CT) was used to calculate the rate of porosity of foraminifera at each depth. Concentrations of Fe, Mn, and P decrease with depth and vice versa for Mg. As a result of the μ-XAFS analysis, P in the soil exists as organic phosphorus and apatite. Phosphorous detected from the upper layer was found to distribute heterogeneously in the particles, which was observed as punctate pattern by the SEM observation. The ICP-MS results showed

  19. Uncharted waters: Bivalves of midway atoll and integrating mathematics into biology education

    Science.gov (United States)

    McCully, Kristin M.

    To protect and conserve the Earth's biodiversity and ecosystem services, it is important not only to understand and conserve species and ecosystems, but also to instill an understanding and appreciation for biodiversity and ecosystem services in the next generations of both scientists and citizens. Thus, this dissertation combines research into the ecology and identity of large bivalves at Midway Atoll in the Northwestern Hawaiian Islands (NWHI) with research on pedagogical strategies for integrating mathematics into undergraduate biology education. The NWHI is one of the few remaining large, mainly intact, predator-dominated coral reef ecosystems and one of the world's largest marine protected areas. Previous bivalve studies focused on the black-lipped pearl oyster, Pinctada margaritifera, which was heavily harvested in the late 1920s, has not recovered, and is now a candidate species for restoration. First, I combined remote sensing, geographic information systems, SCUBA, and mathematical modeling to quantify the abundance, spatial distributions, and filtration capacity of large epifaunal bivalves at Midway Atoll. These bivalves are most abundant on the forereef outside the atoll, but densities are much lower than reported on other reefs, and Midway's bivalves are unlikely to affect plankton abundance and productivity inside the lagoon. Second, I used molecular techniques and phylogenetic reconstructions to identify pearl oysters (Pinctada) from Midway Atoll as P. maculata , a species not previously reported in Hawaii. As a small morphologically cryptic species, P. maculata may be a native species that has not been collected previously, a native species that has been identified incorrectly as the morphologically similar P. radiata, or it may be a recent introduction or natural range extension from the western Pacific. Finally, I review science education literature integrating mathematics into undergraduate biology curricula, and then present and evaluate a

  20. On the occurrence of Bullia tranquebarica (Roding) Nassaridae (Gastropoda) in Kavaratti atoll (Lakshadweep)

    Digital Repository Service at National Institute of Oceanography (India)

    Namboodiri, P.N.; Sivadas, P.

    A live buccinid gastropod Bullia tranquebarica belonging to family Nassaridae was collected from Kavaratti atoll in Lakshadweep island of Indian Ocean. Interesting pattern of its distribution is described. This is the second record of occurrence...

  1. 2007 Reson 8101ER Multibeam Sonar Data from Cruise AHI0701 - Wake Atoll

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Reson 8101ER multibeam Data were collected between 19 April - 9 May 2007 aboard NOAA Survey Launch Acoustic Habitat Investigator (AHI) at Wake Atoll, Western Pacific...

  2. Marine biological survey of ROI-NAMUR outfall at the United States Army Kwajalein Atoll, Republic of the Marshall Islands, May 2000 (NODC Accession 0000653)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Roi-Namur is located at the northernmost tip of Kwajalein Atoll, approximately 64 kilometers north of the U.S. Army Kwajalein Atoll (USAKA) central command post on...

  3. Hydrogeology and geochemistry of the freshwater lens on Roi Namur atoll, the Republic of the Marshall Islands

    Science.gov (United States)

    Swarzenski, P. W.

    2015-12-01

    More than 90% of the world's ~400 larger atoll islands are located in the Pacific and Indian Oceans and are inhabited by ~ 3/4 million people. As ground elevations of these atolls rarely exceed a few meters above mean sea level, atoll communities must rely precariously on finite resources, including fresh water and land. When demand for water exceeds precipitation rates, fresh groundwater may provide an additional, albeit also limited resource. The shape and size of this freshwater lens is controlled by precipitation, infiltration, discharge, and groundwater pumping, as well as hydrogeologic characteristics of the aquifer, and climate. Small atoll islands like Roi Namur on Kwajalein perhaps best illustrate the strong interdependence of the islet's depositional history and geochemical transformations that occur within the shallow aquifer and its host rock. This study utilized electrical resistivity tomography (ERT) to define the position of the freshwater lens above underlying seawater and to examine scales of freshwater /saltwater mixing. Time series Rn-222 measurements were used to evaluate groundwater discharge rates to the coastal waters, and a suite of groundwater geochemical tracers, including select nutrients, trace elements, and water isotopes, were used to develop a better understanding of how the fresh water lens will likely to respond to external perturbations, such as managed recharge, and the inevitability of future marine over wash events that will be become more frequent and severe under expected sea level rise.

  4. CRED REA Algal Assessments, Midway Atoll, Northwestern Hawaiian Islands 2003 (NODC Accession 0010352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 9 sites at Midway Atoll in the...

  5. CRED REA Algal Assessments, Midway Atoll, Northwestern Hawaiian Islands 2004 (NODC Accession 0010352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 9 sites at Midway Atoll in the...

  6. Pisces, Anguilliformes, Moringuidae, Moringua edwardsi (Jordan and Bollman, 1889: First record in Atol das Rocas, northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Paiva, C. C.

    2010-01-01

    Full Text Available Moringua edwardsi is recorded for the first time at Atol das Rocas, northeastern Brazil. Previous records of thespecies were located in the western Atlantic Ocean, from Florida to southeastern Brazil, but with many gaps between theseregions. A single specimen was collected in Atol das Rocas in July 2007 and it is deposited in the Dias da Rocha IchthyologicalCollection. The new record of M. edwardsi fills a geographic distribution gap of this species and complements the inventoryof fish species inhabiting one of the most unique marine protected areas in the world.

  7. CRED REA Coral Population Parameters at Kure Atoll, NW Hawaiian Islands (NWHI), 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 9 sites at Kure Atoll in the NW...

  8. Electromagnetic methods for mapping freshwater lenses on Micronesian atoll islands

    Science.gov (United States)

    Anthony, S.S.

    1992-01-01

    The overall shape of freshwater lenses can be determined by applying electromagnetic methods and inverse layered-earth modeling to the mapping of atoll island freshwater lenses. Conductivity profiles were run across the width of the inhabited islands at Mwoakilloa, Pingelap, and Sapwuahfik atolls of the Pohnpei State, Federated States of Micronesia using a dual-loop, frequency-domain, electromagnetic profiling system. Six values of apparent conductivity were recorded at each sounding station and were used to interpret layer conductivities and/or thicknesses. A three-layer model that includes the unsaturated, freshwater, and saltwater zones was used to simulate apparent-conductivity data measured in the field. Interpreted results were compared with chloride-concentration data from monitoring wells and indicate that the interface between freshwater and saltwater layers, defined from electromagnetic data, is located in the upper part of the transition zone, where the chloride-concentration profile shows a rapid increase with depth. The electromagnetic method can be used to interpret the thickness of the freshwater between monitoring wells, but can not be used to interpret the thickness of freshwater from monitoring wells to the margin of an island. ?? 1992.

  9. Whale shark economics: a valuation of wildlife tourism in South Ari Atoll, Maldives

    KAUST Repository

    Cagua, Edgar F.; Collins, Neal; Hancock, James; Rees, Richard

    2014-01-01

    Whale sharks attract large numbers of tourists, divers and snorkelers each year to South Ari Atoll in the Republic of Maldives. Yet without information regarding the use and economic extent of the attraction, it is difficult to prioritize

  10. Studies on the intertidal macrofauna of the sandy beach at Kavarati atoll (Lakshadweep)

    Digital Repository Service at National Institute of Oceanography (India)

    Narayanan, B.; Sivadas, P.

    The distribution of macrofauna in Kavaratti Atoll is studied in the intertidal region for over a period of 13 months. Several diversity in the faunal composition was not observed. The polychaete Scoloplos sp. and the bivalve Mesodesma glabratum were...

  11. The radiological situation at the atolls of Mururoa and Fangataufa. Proceedings of a conference

    International Nuclear Information System (INIS)

    1998-08-01

    In January 1996, France's programme of experiences nucleaires (nuclear experiments) at the atolls of Mururoa and Fangataufa ceased, and soon after that the French Government requested the International Atomic Energy Agency (IAEA) to carry out a study of the radiological situation at the two atolls. The study of the Radiological Situation at the Atolls of Mururoa and Fangataufa lasted almost two years, giving rise to a number of reports which are being issued by the IAEA. From 30 June to 3 July 1998, the IAEA hosted, in Vienna, an International Conference on the Study, the main purpose being to facilitate discussion of the results of the study by the scientific community and other interested parties. The Conference was presided over by Eduardo Bobadilla Lopez of Chile. These proceedings contain the opening addresses of the Conference, a presentation made by a senior representative of France's Commissariat a l'energie atomique and closing remarks by the President of the Conference, by E. Gail de Planque, Chairman of the International Advisory Committee and by Mohamed ElBaradei, Director General of the IAEA. the also contain edited texts reflecting the discussions which took place during the Conference, mainly after the technical presentations covering the various aspects of the Study. These presentations generally paralleled the Main Report on the Study, to which reference is made in the edited texts

  12. Plutonium and americium behavior in coral atoll environments

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Jokela, T.A.; Brunk, J.L.; Eagle, R.J.

    1984-01-01

    Inventories of 239+240 Pu and 241 Am greatly in excess of global fallout levels persist in the benthic environments of Bikini and Enewetak Atolls. Quantities of 239+240 Pu and lesser amounts of 241 Am are continuously mobilizing from these sedimentary reservoirs. The amount of 239+240 Pu mobilized to solution at any time represents 0.08 to 0.09% of the sediment inventories to a depth of 16 cm. The mobilized 239+240 Pu has solute-like characteristics and different valence states coexist in solution - the largest fraction of the soluble plutonium is in an oxidized form (+V,VI). The adsorption of plutonium to sediments is not completely reversible because of changes that occur in the relative amounts of the mixed oxidation states in solution with time. Further, any characteristics of 239+240 Pu described at one location may not necessarily be relevant in describing its behavior elsewhere following mobilization and migration. The relative amounts of 241 Am to 239+240 Pu in the sedimentary deposits at Enewetak and Bikini may be altered in future years because of mobilization and radiological decay. Mobilization of 239+240 Pu is not a process unique to these atolls, and quantities in solution derived from sedimentary deposits can be found at other global sites. These studies in the equatorial Pacific have significance in assessing the long-term behavior of the transuranics in any marine environment. 22 references, 1 figure, 13 tables

  13. Symbiodinium spp. associated with scleractinian corals from Dongsha Atoll (Pratas), Taiwan, in the South China Sea.

    Science.gov (United States)

    Keshavmurthy, Shashank; Tang, Kuo-Hsun; Hsu, Chia-Min; Gan, Chai-Hsia; Kuo, Chao-Yang; Soong, Keryea; Chou, Hong-Nong; Chen, Chaolun Allen

    2017-01-01

    Dongsha Atoll (also known as Pratas) in Taiwan is the northernmost atoll in the South China Sea and a designated marine national park since 2007. The marine park's scope of protection covers the bio-resources of its waters in addition to uplands, so it is important to have data logging information and analyses of marine flora and fauna, including their physiology, ecology, and genetics. As part of this effort, we investigated Symbiodinium associations in scleractinian corals from Dongsha Atoll through surveys carried out at two depth ranges (shallow, 1-5 m; and deep, 10-15 m) in 2009 and during a bleaching event in 2010. Symbiodinium composition was assessed using restriction fragment length polymorphism (RFLP) of 28S nuclear large subunit ribosomal DNA (nlsrDNA). Our results showed that the 796 coral samples from seven families and 20 genera collected in 2009 and 132 coral samples from seven families and 12 genera collected in 2010 were associated with Symbiodinium C, D and C+D. Occurrence of clade D in shallow water (24.5%) was higher compared to deep (14.9%). Due to a bleaching event in 2010, up to 80% of coral species associated with Symbiodinium C underwent moderate to severe bleaching. Using the fine resolution technique of denaturing gradient gel electrophoresis (DGGE) of internal transcribed spacer 2 (ITS2) in 175 randomly selected coral samples, from 2009 and 2010, eight Symbiodinium C types and two Symbiodinium D types were detected. This study is the first baseline survey on Symbiodinium associations in the corals of Dongsha Atoll in the South China Sea, and it shows the dominance of Symbiodinium clade C in the population.

  14. Marine species survey of Johnson Atoll, Central Pacific Ocean June 2000 (NODC Accession 0000697)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The marine biota of Johnston atoll was surveyed for nonindigenous species in June, 2000 with observations and collections made by investigators using Scuba. Eleven...

  15. Radiological and chemical studies of the ground water at Enewetak Atoll. 1. Sampling, field measurements, and analytical methods

    International Nuclear Information System (INIS)

    Marsh, K.V.; Wong, K.M.; Holladay, G.; Noshkin, V.E.; Buddemeier, R.

    1975-01-01

    A research program to study the ground water on several of the islets in the Enewetak Atoll is being conducted jointly by Lawrence Livermore Laboratory and the University of Hawaii under the sponsorship of ERDA Division of Biology and Environmental Research. The purpose is to provide data characterizing the ground water for possible use by returning Marshallese and to investigate the hydrology and recycling of radionuclides in an atoll environment. This first of a series of reports describes the sampling locations, field operations, and methods of analysis

  16. Clipperton, a possible future for atoll lagoons

    Science.gov (United States)

    Charpy, L.; Rodier, M.; Couté, A.; Perrette-Gallet, C.; Bley-Loëz, C.

    2010-09-01

    Closure of the Clipperton Island atoll (10°17' N 109°13' W), now a meromictic lake, is estimated to have occurred between 1839 and 1849. It was still closed in 2005. Brackish waters in the upper layer (0-10 m) were oxygenated, while saline waters in the deep layer (>20 m) were anoxic. Allowing for the methodological difficulties of earlier measurements, the physical characteristics of the lagoon did not seem to have changed significantly since the last expedition (1980). The intermediate layer between brackish and saline waters was characterized by a strong density gradient and a temperature inversion of up to 1.6°C. Microbial activity, water exchange between the deep layer and surrounding oceanic waters and the geothermal flux hypothesis are discussed. The low DIN and SRP concentrations observed in the upper layer, despite high nutrient input by seabird droppings, reflect the high nutrient uptake by primary producers as attested by the elevated overall gross primary production (6.6 g C m-2 day-1), and high suspended photosynthetic biomass (2.23 ± 0.23 μg Chl a l-1) and production (263 ± 27 μg C l-1 day-1). Phytoplankton composition changed in 67 years with the advent of new taxa and the disappearance of previously recorded species. The freshwater phytoplanktonic community comprised 43 taxa: 37 newly identified during the expedition and 6 previously noted; 16 species previously found were not seen in 2005. The closure of the lagoon, combined with the positive precipitation-evaporation budget characteristic of the region, has induced drastic changes in lagoon functioning compared with other closed atolls.

  17. Marine Species Survey of Johnston Atoll, Central Pacific Ocean, June 2000 (NODC Accession 0000670)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The marine biota of Johnston atoll was surveyed for non-indigenous species in June, 2000 with observations and collections made by investigators using Scuba. Eleven...

  18. Avian disease assessment in seabirds and non-native passerines birds at Midway Atoll NWR

    Science.gov (United States)

    LaPointe, Dennis A.; Atkinson, Carter T.; Klavitter, John L.

    2013-01-01

    Midway Atoll in the Northwestern Hawaiian Islands supports the largest breeding colony of Laysan albatross (Phoebastria immutabilis) in the world and is a proposed site for the translocation of endangered Northwestern Hawaiian Island passerine birds such as the Nihoa finch (Telespiza ultima), Nihoa millerbird (Acrocephalus familiaris kingi), or Laysan finch (Telespiza cantans). On the main Hawaiian Islands, introduced mosquito-borne avian malaria (Plasmodium relictum) and avian pox (Avipoxvirus) have contributed to the extinction and decline of native Hawaiian avifauna. The mosquito vector (Culex quinquefasciatus) is present on Sand Island, Midway Atoll, where epizootics of Avipoxvirus have been reported among nestling Laysan albatross, black-footed albatross (Phoebastria nigripes), and red-tailed tropicbirds (Phaethon rubricauda) since 1963. Two introduced passerines, the common canary (Serinus canaria) and the common myna (Acridotheres tristis), are also present on Sand Island and may serve as reservoirs of mosquito-borne pathogens. Assessing disease prevalence and transmission potential at Midway Atoll National Wildlife Refuge (NWR) is a critical first step to translocation of Nihoa endemic passerines. In May 2010 and April 2012 we surveyed Midway Atoll NWR for mosquitoes and evidence of mosquito-borne disease. Although we did not observe active pox infections on albatross nestlings in May 2010, active infections were prevalent on albatross nestlings in April 2012. Presumptive diagnosis of Avipoxvirus was confirmed by PCR amplification of the Avipoxvirus 4b core protein gene from lesions collected from 10 albatross nestlings. Products were sequenced and compared to 4b core protein sequences from 28 Avipoxvirus isolates from the Hawaiian Islands and other parts of the world. Sequences from all Midway isolates were identical and formed a clade with other Avipoxvirus isolates from seabirds that was distinct from other Avipoxvirus isolates from the Hawaiian Islands

  19. Most atolls will be uninhabitable by the mid-21st century because of sea-level rise exacerbating wave-driven flooding

    Science.gov (United States)

    Storlazzi, Curt; Gingerich, Stephen B.; van Dongeren, Ap; Cheriton, Olivia; Swarzenski, Peter W.; Quataert, Ellen; Voss, Clifford I.; Field, Donald W.; Annamalai, Hariharasubramanian; Piniak, Greg A.; McCall, Robert T.

    2018-01-01

    Sea levels are rising, with the highest rates in the tropics, where thousands of low-lying coral atoll islands are located. Most studies on the resilience of these islands to sea-level rise have projected that they will experience minimal inundation impacts until at least the end of the 21st century. However, these have not taken into account the additional hazard of wave-driven overwash or its impact on freshwater availability. We project the impact of sea-level rise and wave-driven flooding on atoll infrastructure and freshwater availability under a variety of climate change scenarios. We show that, on the basis of current greenhouse gas emission rates, the nonlinear interactions between sea-level rise and wave dynamics over reefs will lead to the annual wave-driven overwash of most atoll islands by the mid-21st century. This annual flooding will result in the islands becoming uninhabitable because of frequent damage to infrastructure and the inability of their freshwater aquifers to recover between overwash events. This study provides critical information for understanding the timing and magnitude of climate change impacts on atoll islands that will result in significant, unavoidable geopolitical issues if it becomes necessary to abandon and relocate low-lying island states.

  20. The radiological situation at the atolls of Mururoa and Fangataufa. Main report

    International Nuclear Information System (INIS)

    1998-01-01

    Between 1966 and 1996, France conducted 193 'experiences nucleaires' (nuclear experiments - a term used by the French authorities to include the full testing of nuclear weapons and the conduct of certain safety trails) above and beneath the atolls of Mururoa and Fangataufa in the Tuamotu Archipelago of French Polynesia. All French testing ceased on 27 January 1996. Before the completion of the last series of tests the Government of France requested the International Atomic Energy Agency (IAEA) to conduct a study to assess the radiological impact of the tests. The IAEA agreed to carry out a study - the Study of the Radiological Situation at the Atolls of Mururoa and Fangataufa - for the purpose of ascertaining whether, as a consequence of the tests, radiological hazards exist now or will exist in the future, and making recommendations on the form, scale and duration of any monitoring, remedial action or follow-up action that might be required. An International Advisory Committee (IAC) was convened by the Director General of the IAEA to provide scientific direction and guidance to the IAEA in the conduct of the Study and to prepare a report on the Study's findings, conclusions and recommendations. The IAC's first formal meeting took place in Vienna on 13-14 April 1996 and its final one, also in Vienna, on 3-5 February 1998. This publication constitutes one of several reports of the IAC to Director General describing the conduct of the Study and its findings, conclusions and recommendations. The French Government provided much of the information used in the Study. This information was independently evaluated by Study participants and, where practicable, validated. In addition to the information provided by the French Government, a small amount of information had been published in the open literature on measured levels of certain radionuclides ( 60 Co, 90 Sr, 137 Cs and 239+240 Pu) in the environment of the atolls, and reports of three scientific missions to the atolls

  1. Plutonium radionuclides in the ground waters at Enewetak Atoll

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Marsh, K.; Eagle, R.; Holladay, G.; Buddemeier, R.W.

    1975-01-01

    In 1974 a groundwater program was initiated at Eniwetok Atoll to study systematically the hydrology and the ground water geochemistry on selected islands of the Atoll. The program provides chemical and radiochemical data for assessment of water quality on those islands designated for rehabilitation. These and other data are used to interpret the mechanisms by which radionuclides are cycled in the soil-groundwater system. Because of the international concern over the long-term buildup, availability, and transport of plutonium in the environment, this program emphasizes analysis of the element. The results of the study show that on all islands sampled, small quantities of plutonium radionuclides have migrated through the soil columns and are redistributed throughout the groundwater reservoirs. The observed maximum surface concentrations are less than 0.02 percent of the maximal recommended concentration for drinking water. Concentrations of 137 Cs are found to correlate with water freshness, but those of 239 , 240 Pu show no such relationship. The mechanisms moving 239 , 240 Pu through the ground water reservoirs are independent of the processes controlling the cycling of 137 Cs and fresh water. A reasonable linear correlation is found between mean surface-water concentrations and soil burdens. This indicates that the quantities of 239 , 240 Pu migrating to the groundwater surface layers are, to a first approximation, independent of the physical, chemical or biological characteristics of the islands. (auth)

  2. CRED REA Coral Population Parameters at Palmyra Atoll, Pacific Remote Island Areas (PRIAs), 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 13 sites at Palmyra Atoll in the...

  3. Symbiodinium spp. associated with scleractinian corals from Dongsha Atoll (Pratas, Taiwan, in the South China Sea

    Directory of Open Access Journals (Sweden)

    Shashank Keshavmurthy

    2017-01-01

    Full Text Available Dongsha Atoll (also known as Pratas in Taiwan is the northernmost atoll in the South China Sea and a designated marine national park since 2007. The marine park’s scope of protection covers the bio-resources of its waters in addition to uplands, so it is important to have data logging information and analyses of marine flora and fauna, including their physiology, ecology, and genetics. As part of this effort, we investigated Symbiodinium associations in scleractinian corals from Dongsha Atoll through surveys carried out at two depth ranges (shallow, 1–5 m; and deep, 10–15 m in 2009 and during a bleaching event in 2010. Symbiodinium composition was assessed using restriction fragment length polymorphism (RFLP of 28S nuclear large subunit ribosomal DNA (nlsrDNA. Our results showed that the 796 coral samples from seven families and 20 genera collected in 2009 and 132 coral samples from seven families and 12 genera collected in 2010 were associated with Symbiodinium C, D and C+D. Occurrence of clade D in shallow water (24.5% was higher compared to deep (14.9%. Due to a bleaching event in 2010, up to 80% of coral species associated with Symbiodinium C underwent moderate to severe bleaching. Using the fine resolution technique of denaturing gradient gel electrophoresis (DGGE of internal transcribed spacer 2 (ITS2 in 175 randomly selected coral samples, from 2009 and 2010, eight Symbiodinium C types and two Symbiodinium D types were detected. This study is the first baseline survey on Symbiodinium associations in the corals of Dongsha Atoll in the South China Sea, and it shows the dominance of Symbiodinium clade C in the population.

  4. Spatial distribution of organochlorine contaminants in soil, sediment, and fish in Bikini and Enewetak Atolls of the Marshall Islands, Pacific Ocean.

    Science.gov (United States)

    Wang, Jun; Caccamise, Sarah A L; Wu, Liejun; Woodward, Lee Ann; Li, Qing X

    2011-08-01

    Several nuclear tests were performed at Enewetak and Bikini Atolls in the Marshall Islands between 1946 and 1958. The events at Bikini Atoll involved several ships that were tested for durability during nuclear explosions, and 24 vessels now rest on the bottom of the Bikini lagoon. Nine soil samples were collected from different areas on the two islands of the atoll, and eighteen sediment, nine fish, and one lobster were collected in the vicinity of the sunken ships. Organochlorine pesticides (OCPs), polychlorinated biphenyls (PCBs), and polychlorinated terphenyls (PCTs) in these samples were analyzed using gas chromatography/ion trap mass spectrometry (GC/ITMS). The average recoveries ranged from 78% to 104% for the different PCB congeners. The limits of detection (LOD) for PCBs, PCTs, DDE, DDT, and dieldrin ranged 10-50 pg g(-1). Some fish from Enewetak contained PCBs at a concentration range of 37-137 ng g(-1), dry weight (dw), and most of the soils from Enewetak showed evidence of PCBs (22-392 ng g(-1)dw). Most of the Bikini lagoon sediment samples contained PCBs, and the highest was the one collected from around the Saratoga, an aircraft carrier (1555 ng g(-1)dw). Some of the fish samples, most of the soil samples, and only one of the sediment samples contained 2,2-bis(4-chlorophenyl)-1,1-dichloroethylene (DDE) and PCBs. In addition to PCBs, the soils from Enewetak Atoll contained PCTs. PCTs were not detected in the sediment samples from Bikini Atoll. The results suggest local pollution sources of PCBs, PCTs, and OCPs. Copyright © 2011. Published by Elsevier Ltd.

  5. The radiological situation at the atolls of Mururoa and Fangataufa. Summary report

    International Nuclear Information System (INIS)

    1998-01-01

    Between 1966 and 1996, France conducted 193 'experiences nucleaires' (nuclear experiments - a term used by the French authorities to include the full testing of nuclear weapons and the conduct of certain safety trails) above and beneath the atolls of Mururoa and Fangataufa in the Tuamotu Archipelago of French Polynesia. All French testing ceased on 27 January 1996. Before the completion of the last series of tests the Government of France requested the International Atomic Energy Agency (IAEA) to conduct a study to assess the radiological impact of the tests. The IAEA agreed to carry out a study - the Study of the Radiological Situation at the Atolls of Mururoa and Fangataufa - for the purpose of ascertaining whether, as a consequence of the tests, radiological hazards exist now or will exist in the future, and making recommendations on the form, scale and duration of any monitoring, remedial action or follow-up action that might be required. An International Advisory Committee (IAC) was concerned by the Director General of the IAEA to provide scientific direction and guidance to the IAEA in the conduct of the Study and to prepare a report on the Study's findings, conclusions and recommendations. The IAC's first formal meeting took place in Vienna on 13-14 April 1996 and its final one, also in Vienna, on 3-5 February 1998. The Summary Report presents a comprehensive summary of the Main Report, including its findings, conclusions and recommendations. The purpose of this Summary Report on the Study of the Radiological Conditions at the Atolls of Mururoa and Fangataufa is to present a summary account of the Study together with its findings, conclusions and recommendation for the benefit of a wider audience. For a comprehensive scientific account, the reader is referred to the Main Report and the detailed Technical Report for the Study

  6. The terrestrial phosphorus economy of mid-Pacific atolls: Implications for the future

    Energy Technology Data Exchange (ETDEWEB)

    Rodgers, K.A. [Auckland Univ. (New Zealand). Dept. of Geology

    1998-03-01

    Major subsystems of the terrestrial phosphorus cycle on the densely populated, 142 ha motu of Fogafale, are: carbonate substrate ({approx} 10{sup 3} g P t{sup -1}), groundwater ({approx} 0.4 g P t{sup -1}), terrestrial flora ({approx} 0.22 t P ha{sup -1}) and fauna ({approx} 18 kg P ha{sup -1}). Freshwater provides the principal medium for terrestrial geochemical atoll processes and is the central recycling plant for phosphorus from atmospheric fallout and decomposition of biotic waste. Present data cannot determine precise fluxes within and between all subsystems, but perturbations, resulting from increasing human populations and changing land use, may be estimated. Changes in Fogafale`s biotic phosphorus capitals and increasing phosphorus-containing imports have skewed fluxes and transfer routes of biogenic waste. Atolls are dynamic systems, able to recover from environmental disruptions, but the sustainability and effectiveness of underlying biogeochemical cycles require quantification, monitoring and nurturing. In particular, the integrity of Fogafale`s essential fresh groundwater needs to be ascertained and protected 40 refs, 7 figs, 2 tabs

  7. Coexistence of low coral cover and high fish biomass at Farquhar Atoll, Seychelles.

    Science.gov (United States)

    Friedlander, Alan M; Obura, David; Aumeeruddy, Riaz; Ballesteros, Enric; Church, Julie; Cebrian, Emma; Sala, Enric

    2014-01-01

    We report a reef ecosystem where corals may have lost their role as major reef engineering species but fish biomass and assemblage structure is comparable to unfished reefs elsewhere around the world. This scenario is based on an extensive assessment of the coral reefs of Farquhar Atoll, the most southern of the Seychelles Islands. Coral cover and overall benthic community condition at Farquhar was poor, likely due to a combination of limited habitat, localized upwelling, past coral bleaching, and cyclones. Farquhar Atoll harbors a relatively intact reef fish assemblage with very large biomass (3.2 t ha(-1)) reflecting natural ecological processes that are not influenced by fishing or other local anthropogenic factors. The most striking feature of the reef fish assemblage is the dominance by large groupers, snappers, and jacks with large (>1 m) potato cod (Epinephelus tukula) and marbled grouper (E. polyphekadion), commonly observed at many locations. Napoleon wrasse (Cheilinus undulatus) and bumphead parrotfish (Bolbometopon muricatum) are listed as endangered and vulnerable, respectively, but were frequently encountered at Farquhar. The high abundance and large sizes of parrotfishes at Farquhar also appears to regulate macroalgal abundance and enhance the dominance of crustose corallines, which are a necessary condition for maintenance of healthy reef communities. Overall fish biomass and biomass of large predators at Farquhar are substantially higher than other areas within the Seychelles, and are some of the highest recorded in the Indian Ocean. Remote islands like Farquhar Atoll with low human populations and limited fishing pressure offer ideal opportunities for understanding whether reefs can be resilient from global threats if local threats are minimized.

  8. Coexistence of low coral cover and high fish biomass at Farquhar Atoll, Seychelles.

    Directory of Open Access Journals (Sweden)

    Alan M Friedlander

    Full Text Available We report a reef ecosystem where corals may have lost their role as major reef engineering species but fish biomass and assemblage structure is comparable to unfished reefs elsewhere around the world. This scenario is based on an extensive assessment of the coral reefs of Farquhar Atoll, the most southern of the Seychelles Islands. Coral cover and overall benthic community condition at Farquhar was poor, likely due to a combination of limited habitat, localized upwelling, past coral bleaching, and cyclones. Farquhar Atoll harbors a relatively intact reef fish assemblage with very large biomass (3.2 t ha(-1 reflecting natural ecological processes that are not influenced by fishing or other local anthropogenic factors. The most striking feature of the reef fish assemblage is the dominance by large groupers, snappers, and jacks with large (>1 m potato cod (Epinephelus tukula and marbled grouper (E. polyphekadion, commonly observed at many locations. Napoleon wrasse (Cheilinus undulatus and bumphead parrotfish (Bolbometopon muricatum are listed as endangered and vulnerable, respectively, but were frequently encountered at Farquhar. The high abundance and large sizes of parrotfishes at Farquhar also appears to regulate macroalgal abundance and enhance the dominance of crustose corallines, which are a necessary condition for maintenance of healthy reef communities. Overall fish biomass and biomass of large predators at Farquhar are substantially higher than other areas within the Seychelles, and are some of the highest recorded in the Indian Ocean. Remote islands like Farquhar Atoll with low human populations and limited fishing pressure offer ideal opportunities for understanding whether reefs can be resilient from global threats if local threats are minimized.

  9. CRED REA Algal Assessments, Pearl and Hermes Atoll, Northwestern Hawaiian Islands, 2002 (NODC Accession 0010352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 14 sites at Pearl and Hermes Atoll...

  10. CRED REA Algal Assessments, Pearl and Hermes Atoll, Northwestern Hawaiian Islands 2003 (NODC Accession 0010352)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Twelve quadrats were sampled along 2 consecutively-placed, 25m transect lines as part of Rapid Ecological Assessments conducted at 15 sites at Pearl and Hermes Atoll...

  11. CRED REA Coral Population Parameters at Johnston Atoll, Pacific Remote Island Areas (PRIAs) in 2008

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 4 sites at Johnston Atoll in the...

  12. CRED REA Coral Population Parameters at Pearl and Hermes Atoll, NW Hawaiian Islands (NWHI), 2006

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Belt transects along 2 consecutively-placed, 25m transect lines were surveyed as part of Rapid Ecological Assessments conducted at 13 sites at Pearl and Hermes Atoll...

  13. Groundwater movement on a Low-lying Carbonate Atoll Island and its Response to Climatic and Sea-level Fluctuations: Roi Namur, Republic of the Marshall Islands

    Science.gov (United States)

    Oberle, F. J.; Swarzenski, P. W.; Storlazzi, C. D.

    2017-12-01

    Atoll islands, most of which only average 1-2 meters above today's sea level, provide a tremendous natural laboratory in which to study and better understand the intensifying impacts of high rates of sea-level rise on tropical reef-lined islands. These islands are unique and on the frontline of negative societal impacts due to their geologic structure and limited water supply. Groundwater resources on atolls are typically minimal due to the low elevation and small surface area of the islands and are also subject to recurring droughts, and more frequent, storm-driven seawater overwash events. Although groundwater is the principal means of freshwater storage on atoll islands and is a major factor in determining the overall sustainability of island settlements, hydrological data on how an aquifer will response to changes in sea-level rise or storm-driven overwash remain limited. Here we present high-resolution time series hydrogeological and geochemical data from a 16 month study to determine the role of an atoll's carbonate geology, land use, and atmospheric and oceanographic forcing in driving coastal groundwater exchange including submarine groundwater discharge on the island of Roi-Namur on Kwajalein Atoll in the Republic of the Marshall Islands. This information can provide new estimates on the recovery and resilience of coastal groundwater resources on similar islands that are expected to experience climate change-driven perturbations.

  14. Drivers of shoreline change in atoll reef islands of the Tuamotu Archipelago, French Polynesia

    Science.gov (United States)

    Duvat, Virginie K. E.; Salvat, Bernard; Salmon, Camille

    2017-11-01

    This paper increases by around 30% the sample of atoll reef islands studied from a shoreline change perspective, and covers an under-studied geographical area, i.e. the French Tuamotu Archipelago. It brings new irrefutable evidences on the persistence of reef islands over the last decades, as 77% of the 111 study islands exhibited areal stability while 15% and 8% showed expansion and contraction, respectively. This paper also addresses a key research gap by interpreting the major local drivers controlling recent shoreline and island change, i.e. tropical cyclones and seasonal swells, sediment supply by coral reefs and human activities. The 1983 tropical cyclones had contrasting impacts, depending on the shoreline indicator considered. While they generally caused a marked retreat of the stability line, the base of the beach advanced at some locations, as a result of either sediment reworking or fresh sediment inputs. The post-cyclone fair weather period was characterised by reversed trends indicating island morphological readjustment. Cyclonic waves contributed to island upwards growth, which reached up to 1 m in places, through the transfer of sediments up onto the island surface. However, the steep outer slopes of atolls limited sediment transfers to the reef flat and island system. We found that 57% of the study islands are disturbed by human activities, including 'rural' and uninhabited islands. Twenty-six percent of these islands have lost the capacity to respond to ocean-climate related pressures, including the 'capital' islands concentrating atolls' population, infrastructures and economic activities, which is preoccupying under climate change.

  15. Forecasting the impact of storm waves and sea-level rise on Midway Atoll and Laysan Island within the Papahānaumokuākea Marine National Monument—a comparison of passive versus dynamic inundation models

    Science.gov (United States)

    Storlazzi, Curt D.; Berkowitz, Paul; Reynolds, Michelle H.; Logan, Joshua B.

    2013-01-01

    Two inundation events in 2011 underscored the potential for elevated water levels to damage infrastructure and affect terrestrial ecosystems on the low-lying Northwestern Hawaiian Islands in the Papahānaumokuākea Marine National Monument. The goal of this study was to compare passive "bathtub" inundation models based on geographic information systems (GIS) to those that include dynamic water levels caused by wave-induced set-up and run-up for two end-member island morphologies: Midway, a classic atoll with islands on the shallow (2-8 m) atoll rim and a deep, central lagoon; and Laysan, which is characterized by a deep (20-30 m) atoll rim and an island at the center of the atoll. Vulnerability to elevated water levels was assessed using hindcast wind and wave data to drive coupled physics-based numerical wave, current, and water-level models for the atolls. The resulting model data were then used to compute run-up elevations using a parametric run-up equation under both present conditions and future sea-level-rise scenarios. In both geomorphologies, wave heights and wavelengths adjacent to the island shorelines increased more than three times and four times, respectively, with increasing values of sea-level rise, as more deep-water wave energy could propagate over the atoll rim and larger wind-driven waves could develop on the atoll. Although these increases in water depth resulted in decreased set-up along the islands’ shorelines, the larger wave heights and longer wavelengths due to sea-level rise increased the resulting wave-induced run-up. Run-up values were spatially heterogeneous and dependent on the direction of incident wave direction, bathymetry, and island configuration. Island inundation was modeled to increase substantially when wave-driven effects were included, suggesting that inundation and impacts to infrastructure and terrestrial habitats will occur at lower values of predicted sea-level rise, and thus sooner in the 21st century, than suggested

  16. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 6. Doses due to radioactive materials present in the environment or released from the atolls

    International Nuclear Information System (INIS)

    1998-08-01

    In the previous volumes of this Report the concentrations of residual radioactivity in the environment of Mururoa and Fangataufa atolls have been described, and assessment made of the releases to the environment in the future. The further step in radiological assessment is the derivation of radiation doses that arise to actually or potentially exposed populations, from these concentrations and releases. These doses are estimated in this report. The existence of a hypothetical population resident on Mururoa is postulated as the group which would be most exposed. Doses to this group are estimated together with doses to maximally exposed residents on nearby South Pacific islands, and further afield. An assessment of the potential environmental impact of the residual contaminant radionuclides from the nuclear weapons testing at Mururoa and Fangataufa requires estimates of the incremental dose rates to a variety of marine organisms inhabiting a number of different ecological niches. These estimated dose rates provide the only secure basis for an assessment of the potential radiation effects in the organisms. The approach adopted for this assessment is that employed in a number of recent studies and adapts the dosimetry models for the particular organisms of interest in the atoll environment

  17. Coral reef fish assemblages at Clipperton Atoll (Eastern Tropical Pacific and their relationship with coral cover

    Directory of Open Access Journals (Sweden)

    Aurora M. Ricart

    2016-11-01

    Full Text Available Clipperton Atoll, one of the most isolated coral reefs worldwide, is of great scientific interest due to its geomorphology and high levels of endemism. This study explored the reef fish assemblage structure of Clipperton Atoll and its relationship with live coral cover. Nine stations were sampled at three sites and three depths (6, 12 and 20 m around the reef, measuring fish species richness and biomass and hermatypic coral cover (at genus level. We evaluated variation in species richness, biomass and diversity of fish assemblages among sites and depths, as well as the relationship between the entire fish assemblage composition and live coral cover. The results showed that species richness and biomass were similar among sites, but differed across depths, increasing with depth. In contrast, diversity differed among sites but not among depths. Multivariate analyses indicated that fish assemblage composition differed among sites and depths in relation to changes in cover of coral of the genera Pocillopora, Porites, Pavona and Leptoseris, which dominate at different depths. The results showed that fish species richness and diversity were low at Clipperton Atoll and that, in isolated coral reefs with a low habitat heterogeneity and low human disturbance, live coral cover has a significant influence on the spatial variation of the reef fish assemblages. This study highlights the importance of coral habitat structure in shaping coral reef fish assemblages.

  18. Benthic Habitat Maps for Rose Atoll Marine National Monument in American Samoa from 2004 to 2010

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps for Rose Atoll, American Samoa were derived from high resolution, multispectral satellite imagery for 2004, 2006, and 2010. The benthic habitat...

  19. Contraction of the southeast Polynesian interaction sphere and resource depression on Temoe Atoll

    International Nuclear Information System (INIS)

    Weisler, M.I.

    2004-01-01

    The southeast Polynesian interaction sphere, involving most frequently islands in Mangareva and the Pitcairn group, was active for at least five centuries beginning about AD 1000. By western contact in the early seventeenth century, all islands in the Pitcairn group were abandoned, signalling a contraction of the sphere. Systematic survey and excavations were conducted on Temoe Atoll, the next closest island to the main Mangareva group, to determine the spatial and temporal boundaries of that contraction. The excavations in five late prehistoric habitation sites are described, and provide the first subsistence remains from the atoll. These consist of 21,590 bones of fish, bird, turtle, Pacific rat and human as well as 25 kg of shell midden, mostly Turbo gastropods. Reconstructed weights of parrotfish (Scaridae), by far the most common fish taxon, illustrate a decline in size during late prehistory, pointing to exploitation depression. The x-ray fluorescence analysis of volcanic artefacts documents ties with the main Mangarewa group, suggesting that the reduced interaction sphere lasted until the early nineteenth century when Temoe was finally abandoned. (author). 34 refs., 10 figs., 6 tabs

  20. 137Cs inter-plant concentration ratios provide a predictive tool for coral atolls with distinct benefits over transfer factors

    International Nuclear Information System (INIS)

    Robison, William L.; Hamilton, Terry F.; Bogen, Kenneth T.; Conrado, Cynthia L.; Kehl, Steven R.

    2008-01-01

    Inter-plant concentration ratios (IPCR) [Bq g -1137 Cs in coral atoll tree food crops/Bq g -1137 Cs in leaves of native plant species whose roots share a common soil volume] can replace transfer factors (TF) to predict 137 Cs concentration in tree food crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact that tree roots naturally integrate 137 Cs over large volumes of soil. Root absorption of 137 Cs replaces large-scale, expensive soil sampling schemes to reduce variability in 137 Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log-normally distributed (LND) with geometric standard deviation (GSD) = 1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSDs of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD = 1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10-20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples

  1. Revisiting wild stocks of black lip oyster Pinctada margaritifera in the Tuamotu Archipelago: The case of Ahe and Takaroa atolls and implications for the cultured pearl industry

    Science.gov (United States)

    Andréfouët, Serge; Thomas, Yoann; Dumas, Franck; Lo, Cédrik

    2016-12-01

    Spat collecting of the black lip oyster (Pinctada margaritifera) is the foundation of cultured black pearl production, the second source of income for French Polynesia. To understand spat collecting temporal and spatial variations, larval supply and its origin need to be characterized. To achieve this, it is necessary to account for the stock of oysters, its distribution and population characteristics (size distribution, sex-ratio). While the farmed stock in concessions can be easily characterized, the wild stock is elusive. Here, we investigate the distribution and population structure of the wild stock of Ahe and Takaroa atolls using fine-scale bathymetry and in situ census data. Stocks were surprisingly low (∼666,000 and ∼1,030,000 oysters for Ahe and Takaroa respectively) considering these two atolls have both been very successful spat collecting atolls in the past. Furthermore, in Ahe atoll, wild populations are aging with a dominant but small female population. Comparison with the cultured stock population (∼14 millions oysters) and its dominant young male population suggests that to maximize larval supply and spat collecting on the long term, it would be useful to increase the number of females in selected sanctuaries. We discuss the implication of our findings for the long-term management of stocks and for spat collection in pearl farming atolls, and for on-going numerical modelling studies on larval dispersal.

  2. Trophic interactions between larger crocodylians and giant tortoises on Aldabra Atoll, Western Indian Ocean, during the Late Pleistocene.

    Science.gov (United States)

    Scheyer, Torsten M; Delfino, Massimo; Klein, Nicole; Bunbury, Nancy; Fleischer-Dogley, Frauke; Hansen, Dennis M

    2018-01-01

    Today, the UNESCO World Heritage Site of Aldabra Atoll is home to about 100 000 giant tortoises, Aldabrachelys gigantea , whose fossil record goes back to the Late Pleistocene. New Late Pleistocene fossils (age ca . 90-125 000 years) from the atoll revealed some appendicular bones and numerous shell fragments of giant tortoises and cranial and postcranial elements of crocodylians. Several tortoise bones show circular holes, pits and scratch marks that are interpreted as bite marks of crocodylians. The presence of a Late Pleistocene crocodylian species, Aldabrachampsus dilophus , has been known for some time, but the recently found crocodylian remains presented herein are distinctly larger than those previously described. This indicates the presence of at least some larger crocodylians, either of the same or of a different species, on the atoll. These larger crocodylians, likely the apex predators in the Aldabra ecosystem at the time, were well capable of inflicting damage on even very large giant tortoises. We thus propose an extinct predator-prey interaction between crocodylians and giant tortoises during the Late Pleistocene, when both groups were living sympatrically on Aldabra, and we discuss scenarios for the crocodylians directly attacking the tortoises or scavenging on recently deceased animals.

  3. Migration from atolls as climate change adaptation

    DEFF Research Database (Denmark)

    Birk, Thomas Ladegaard Kümmel; Rasmussen, Kjeld

    2014-01-01

    to migration that reduce the efficacy of positive outcomes to both migrants and their home communities, including high transport costs and problems in gaining access to housing, employment and government services in urban destination areas. If it is accepted that voluntary migration may play a positive role...... that migration currently improves access to financial and social capital, reduces pressure on natural resources and makes island communities less vulnerable to extreme weather events and other shocks — all factors that contribute positively to adaptive capacity. It also shows that there are major barriers...... in adaptation to climate change in exposed atoll communities, addressing some of the barriers to migration seems logical. This may be done by efforts to stimulate migrant income opportunities, by improving migrant living conditions and by improving the transport services to the islands....

  4. Rickettsial pathogens and arthropod vectors of medical and veterinary significance on Kwajalein Atoll and Wake Island

    Directory of Open Access Journals (Sweden)

    Durden, L.

    2012-05-01

    Full Text Available Modern surveys of ectoparasites and potential vector-borne pathogens in the Republic of the Marshall Islands and Wake Island are poorly documented. We report on field surveys of ectoparasites from 2010 with collections from dogs, cats, and rats. Five ectoparasites were identified: the cat flea Ctenocephalides felis, a sucking louse Hoplopleura pacifica, the mites Laelaps nuttalli and Radfordia ensifera, and the brown dog tickRhipicephalus sanguineus. Ectoparasites were screened for rickettsial pathogens. DNA from Anaplasma platys, a Coxiella symbiont of Rhipicephalus sanguineus, anda Rickettsia sp. were identified by PCR and DNA sequencing from ticks and fleas on Kwajalein Atoll. An unidentified spotted fever group Rickettsia was detected in a pool of Laelaps nuttalli and Hoplopleura pacifica from Wake Island. The records of Hoplopleura pacifica, Laelaps nuttalli, and Radfordia ensifera and the pathogens are new for Kwajalein Atoll and Wake Island.

  5. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 6. Doses due to radioactive materials present in the environment or released from the atolls

    Energy Technology Data Exchange (ETDEWEB)

    International Advisory Committee, Task Group A

    1998-08-01

    In the previous volumes of this Report the concentrations of residual radioactivity in the environment of Mururoa and Fangataufa atolls have been described, and assessment made of the releases to the environment in the future. The further step in radiological assessment is the derivation of radiation doses that arise to actually or potentially exposed populations, from these concentrations and releases. These doses are estimated in this report. The existence of a hypothetical population resident on Mururoa is postulated as the group which would be most exposed. Doses to this group are estimated together with doses to maximally exposed residents on nearby South Pacific islands, and further afield. An assessment of the potential environmental impact of the residual contaminant radionuclides from the nuclear weapons testing at Mururoa and Fangataufa requires estimates of the incremental dose rates to a variety of marine organisms inhabiting a number of different ecological niches. These estimated dose rates provide the only secure basis for an assessment of the potential radiation effects in the organisms. The approach adopted for this assessment is that employed in a number of recent studies and adapts the dosimetry models for the particular organisms of interest in the atoll environment Refs, figs, tabs. In six volumes

  6. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 3. Inventory of radionuclides underground at the atolls

    International Nuclear Information System (INIS)

    1998-08-01

    The objective of Working Group 3 was to independently estimate the underground inventories of radionuclides, at the French nuclear test site on the atolls of Mururoa and Fangataufa, and to estimate the distribution of radionuclides between four major components - lava, rubble, gas and water - that determines the mobility of radionuclides in the geosphere. The group also provided a summary of the critical damage dimensions, such as the cavity radius, fissure zone radius and the height of the chimney. As a lot of dimensional data were provided by the French Liaison Office the focus of this report has been to compare these data with experience gained from other test sites in the world

  7. Anthropogenic 236U recorded in annually banded coral skeleton at Majuro atoll, the equatorial Pacific

    International Nuclear Information System (INIS)

    Sakaguchi, Aya; Eto, Asuka; Takahashi, Yoshio; Steier, Peter; Yamazaki, Atsuko; Watanabe, Tsuyoshi; Sasaki, Keiichi; Yamano, Hiroya

    2013-01-01

    Historical 236 U/ 238 U atom ratio and concentration of 236 U were determined by Accelerator Mass Spectrometry (AMS) in skeletons of dated modern coral core sample collected from Majuro atoll, equatorial Pacific, to reconstruct anthropogenic 236 U inputs to the Equatorial Pacific. The maximum hydrogen bomb-pulses of 236 U/ 238 U and 236 U concentration, 2.83x10 -9 and 1.85x10 7 atom/g, in an annually resolved coral core were captured in 1954 (Operation Castle at Bikini and Enewetok atolls). The values were abruptly decreased in a few years, and they have been gradually decreased over time. Our results allow studies of not only the present distribution pattern, but gives access to the temporal evolution of 236 U in surface seawater of North Equatorial Current which is introduced to the Japan Sea and the North West Pacific Ocean as Kuroshio and Tsushima currents over the past decades. (author)

  8. 33 CFR 334.1440 - Pacific Ocean at Kwajalein Atoll, Marshall Islands; missile testing area.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Pacific Ocean at Kwajalein Atoll, Marshall Islands; missile testing area. 334.1440 Section 334.1440 Navigation and Navigable Waters CORPS OF ENGINEERS, DEPARTMENT OF THE ARMY, DEPARTMENT OF DEFENSE DANGER ZONE AND RESTRICTED AREA REGULATIONS § 334.1440 Pacific Ocean at Kwajalein...

  9. 137Cs Inter-Plant Concentration Ratios Provide a Predictive Tool for Coral Atolls with Distinct Benefits Over Transfer Factors

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W L; Hamilton, T F; Bogen, K; Corado, C L; Kehl, S R

    2007-07-17

    Inter-plant concentration ratios (IPCR), [Bq g{sup -1} {sup 137}Cs in coral atoll tree food-crops/Bq g{sup -1} {sup 137}Cs in leaves of native plant species whose roots share a common soil volume], can replace transfer factors (TF) to predict {sup 137}Cs concentration in tree food-crops in a contaminated area with an aged source term. The IPCR strategy has significant benefits relative to TF strategy for such purposes in the atoll ecosystem. IPCR strategy applied to specific assessments takes advantage of the fact tree roots naturally integrate 137Cs over large volumes of soil. Root absorption of {sup 137}Cs replaces large-scale, expensive soil sampling schemes to reduce variability in {sup 137}Cs concentration due to inhomogeneous radionuclide distribution. IPCR [drinking-coconut meat (DCM)/Scaevola (SCA) and Tournefortia (TOU) leaves (native trees growing on all atoll islands)] are log normally distributed (LND) with geometric standard deviation (GSD) = 1.85. TF for DCM from Enewetak, Eneu, Rongelap and Bikini Atolls are LND with GSD's of 3.5, 3.0, 2.7, and 2.1, respectively. TF GSD for Rongelap copra coconut meat is 2.5. IPCR of Pandanus fruit to SCA and TOU leaves are LND with GSD = 1.7 while TF GSD is 2.1. Because IPCR variability is much lower than TF variability, relative sampling error of an IPCR field sample mean is up 6- to 10-fold lower than that of a TF sample mean if sample sizes are small (10 to 20). Other IPCR advantages are that plant leaf samples are collected and processed in far less time with much less effort and cost than soil samples.

  10. Geochronology and subsurface stratigraphy of Pukapuka and Rakahanga atolls, Cook Islands: Late Quaternary reef growth and sea level history

    Science.gov (United States)

    Gray, S.C.; Hein, J.R.; Hausmann, R.; Radtke, U.

    1992-01-01

    Eustatic sea-level cycles superposed on thermal subsidence of an atoll produce layers of high sea-level reefs separated by erosional unconformities. Coral samples from these reefs from cores drilled to 50 m beneath the lagoons of Pukapuka and Rakahanga atolls, northern Cook Islands give electron spin resonance (ESR) and U-series ages ranging from the Holocene to 600,000 yr B.P. Subgroups of these ages and the stratigraphic position of their bounding unconformities define at least 5 periods of reef growth and high sea-level (0-9000 yr B.P., 125,000-180,000 yr B.P., 180,000-230,000 yr B.P., 300,000-460,000 yr B.P., 460,000-650,000 yr B.P.). Only two ages fall within error of the last interglacial high sea-level stand (???125,000-135,000 yr B.P.). This paucity of ages may result from extensive erosion of the last intergracial reef. In addition, post-depositional isotope exchange may have altered the time ages of three coral samples to apparent ages that fall within glacial stage 6. For the record to be preserved, vertical accretion during rising sea-level must compensate for surface lowering from erosion during sea-level lowstands and subsidence of the atoll; erosion rates (6-63 cm/1000 yr) can therefore be calculated from reef accretion rates (100-400 cm/1000 yr), subsidence rates (2-6 cm/1000 yr), and the duration of island submergence (8-15% of the last 600,000 yr). The stratigraphy of coral ages indicates island subsidence rates of 4.5 ?? 2.8 cm/1000 yr for both islands. A model of reef growth and erosion based on the stratigraphy of the Cook Islands atolls suggests average subsidence and erosion rates of between 3-6 and 15-20 cm/1000 yr, respectively. ?? 1992.

  11. A history of the people of Bikini following nuclear weapons testing in the Marshall Islands: with recollections and views of elders of Bikini Atoll.

    Science.gov (United States)

    Niedenthal, J

    1997-07-01

    The people of Bikini Atoll were moved from their homeland in 1946 to make way for the testing of 23 nuclear weapons by the United States government, beginning with the world's fourth atomic detonation. The subsequent half-century exodus of the Bikini people included a 2-y stay on Rongerik Atoll, where near starvation resulted, and a 6-mo sojourn on Kwajalein Atoll, where they lived in tents beside a runway used by the U.S. military. In 1948, they were finally relocated to Kili, a small, isolated, 200-acre island owned by the U.S. Trust Territory government. Numerous hardships have been faced there, not the least of which was the loss of skills required for self-sustenance. Located 425 miles south of Bikini, Kili Island is without a sheltered lagoon. Thus for six months of the year, fishing and sailing become futile endeavors. Because of the residual radioactive contamination from the nuclear testing, the majority of the Bikinian population still resides on Kili today. One attempt was made to resettle Bikini in the late 1960's when President Lyndon B. Johnson, on recommendations from the Atomic Energy Commission, declared Bikini Atoll safe for habitation. In 1978, however, it was discovered by the U.S. Department of Energy that in the span of only one year, some of the returned islanders were showing a 75% increase in their body burdens of 137Cs. In 1978, the people residing on Bikini were moved again, this time to a small island in Majuro Atoll. In the early 1980's, the Bikinians filed a class action lawsuit against the U.S. government for damages arising out of the nuclear testing program. Although the claim was dismissed, eventually a $90 million trust fund was established for their local government. Since then the leaders of the people of Bikini residing on Kili Island and Majuro Atoll have been confronted with the immense responsibility of determining how to clean their atoll while at the same time maintaining the health and welfare of their displaced

  12. Population characteristics of the mole crab, Hippa adactyla Fabricius, in the intertidal sediment at Kavaratti Atoll, Lakshadweep Islands

    Digital Repository Service at National Institute of Oceanography (India)

    Ingole, B.S.; Sreepada, R.A.; Ansari, Z.A.; Parulekar, A.H.

    Some population characteristics of a little known mole crab Hippa adactyla from the sandy intertidal habitat of Kavaratti atoll, Lakshadweep islands, were studied for understanding the resource potentials besides some features of breeding behavior...

  13. Stomach nematodes (Mastophorus muris) in rats (Rattus rattus) are associated with coconut (Cocos nucifera) habitat at Palmyra Atoll.

    Science.gov (United States)

    Lafferty, Kevin D; Hathaway, Stacie A; Wegmann, Alex S; Shipley, Frank S; Backlin, Adam R; Helm, Joel; Fisher, Robert N

    2010-02-01

    Black rats ( Rattus rattus ) and their stomach nematodes (Mastophorus muris) were historically introduced to islets at Palmyra Atoll in the central Pacific Line Islands. To investigate patterns of parasitism, we trapped rats and quantified nematodes on 13 islets of various sizes and habitat types. Most rats were parasitized (59%) with an average of 12 worms per infected rat. Islet size did not greatly influence parasite population biology. Nematodes also did not appear to affect rat condition (weight to skull length). The only strong and consistent factor associated with the mean abundance of nematodes in rats was habitat (dominant cover and locally dominant plant species). Thus, nematodes were much more abundant in rats from sites dominated by coconut trees (Cocos nucifera). Coconut trees may also be an introduced species at Palmyra Atoll.

  14. Palmyra Atoll, 2006 Sea Surface Temperature and Meteorological Enhanced Mooring - CRED CREWS Near Real Time and Historical Data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Site Palmyra Atoll, (5.88467, -162.10281 ) ARGOS ID 307-001. Time series data from this mooring provide high resolution sea surface temperature and conductivity, and...

  15. Dispersion of radionuclides potentially released from the Atolls of Mururoa and Fangataufa to neighboring archipelagos

    International Nuclear Information System (INIS)

    Osvath, I.

    1999-01-01

    This paper presents a compartmental model developed to simulate dispersion of radionuclides released to the ocean from the atolls of Mururoa and Fangataufa on a scale of 3000 x 1700 km (150 deg. to 300 deg. S latitude, 130 deg. to 160 deg. W longitude), including the Tuamotu, Cook, Society, Gambier and Austral archipelagos

  16. Invisible Nuclear Catastrophe Consequences of the U.S. Atomic and Hydrogen Bomb Testings in the Marshall Islands: Focusing on the “Overlooked” Ailuk Atoll

    OpenAIRE

    Takemine, Seiichiro

    2018-01-01

    The United States conducted sixty-seven nuclear tests in total at Bikini and Enewetak Atoll in the Marshall Islands between 1946 and 1958. T his article discusses the U.S. nuclear test issues in the Marshall Islands, focusing on the local people who have not been able t o apply for the U.S. compensation, especially those on Ailuk Atoll. Until today, little attention has been given to these areas.Interviews with survivors as well as declassified U.S. documents make it clear that the nuclear te...

  17. The atolls of Mururoa and Fangataufa (French Polynesia). The nuclear testings. Radiological aspects; Les atolls de Mururoa et de Fangataufa (Polynesie Francaise). Les experimentations nucleaires. Aspects radiologiques

    Energy Technology Data Exchange (ETDEWEB)

    Martin, G

    2007-07-01

    This report provides a review of the radiological measures implemented during the thirty year period of French nuclear tests in Polynesian atolls of Mururoa and Fangataufa. It presents full details of the practices deployed throughout these tests, including, in particular, aspects concerning radiological protection for the population and the environment. It contains all the scientific results and measurements of radioactivity performed during this period, providing concrete facts that can be used to assess the consequences these tests have had on the personnel involved, the population and the environment. (author)

  18. Projections of extreme water level events for atolls in the western Tropical Pacific

    Science.gov (United States)

    Merrifield, M. A.; Becker, J. M.; Ford, M.; Yao, Y.

    2014-12-01

    Conditions that lead to extreme water levels and coastal flooding are examined for atolls in the Republic of the Marshall Islands based on a recent field study of wave transformations over fringing reefs, tide gauge observations, and wave model hindcasts. Wave-driven water level extremes pose the largest threat to atoll shorelines, with coastal levels scaling as approximately one-third of the incident breaking wave height. The wave-driven coastal water level is partitioned into a mean setup, low frequency oscillations associated with cross-reef quasi-standing modes, and wind waves that reach the shore after undergoing high dissipation due to breaking and bottom friction. All three components depend on the water level over the reef; however, the sum of the components is independent of water level due to cancelling effects. Wave hindcasts suggest that wave-driven water level extremes capable of coastal flooding are infrequent events that require a peak wave event to coincide with mid- to high-tide conditions. Interannual and decadal variations in sea level do not change the frequency of these events appreciably. Future sea-level rise scenarios significantly increase the flooding threat associated with wave events, with a nearly exponential increase in flooding days per year as sea level exceeds 0.3 to 1.0 m above current levels.

  19. Arthropods of Rose Atoll with special reference to ants and Pulvinaria Urbicola Scales (Hempitera Coccidae) on Pisonia Grandis trees

    Science.gov (United States)

    Banko, Paul C.; Peck, Robert W.; Pendleton, Frank; Schmaedick, Mark; Ernsberger, Kelsie

    2014-01-01

    Rose Atoll, at the eastern end of the Samoan Archipelago, is a small but important refuge for seabirds, shorebirds, and sea turtles. While the vertebrate community is relatively well-studied, the terrestrial arthropod fauna, and its role in ecosystem function, are poorly known. Arthropods may be influencing the decline of Pisonia grandis, an ecologically important tree that once dominated the 6.6 ha of land on Rose Atoll. Reasons for the decline are not fully understood but a facultative relationship between two invasive arthropods, the soft scale Pulvinaria urbicola and ants, likely has contributed to tree death. The primary objectives of this study were to systematically survey the terrestrial arthropod fauna and identify ant species that tend scales on Pisonia. Using an array of standard arthropod collecting techniques, at least 73 species from 20 orders were identified, including nine ant species. Of the ants collected, only Tetramorium bicarinatum and T. simillimum were observed tending scales on Pisonia. No known natural enemies of Pulvinaria scales were found, suggesting little predation on scale populations. Treatment of Pisonia with the systemic insecticide imidacloprid failed to eliminate Pulvinaria scales, although short-term suppression apparently occurred. The arthropod fauna of Rose Atoll is dominated by exotic species that likely have a significant impact on the structure and function of the island’s ecosystem.

  20. Clipperton Atoll Core 2B Stable Isotope (delta 13C, delta 18O) Data for 1893 to 1994

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — 101 year stable isotope record from P. lobata, core 4B, Clipperton Atoll, eastern Pacific. Sampling at annual and 12/year resolution, files clipperton.4B.iso.txt and...

  1. Clipperton Atoll Core 3C Stable Isotope (delta 13C, delta 18O) Data for 1893 to 1994

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — 101 year stable isotope record from P. lobata, core 4B, Clipperton Atoll, eastern Pacific. Sampling at annual and 12/year resolution, files clipperton.4B.iso.txt and...

  2. Clipperton Atoll Core 4B Stable Isotope (delta 13C, delta 18O) Data for 1893 to 1994

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — 101 year stable isotope record from P. lobata, core 4B, Clipperton Atoll, eastern Pacific. Sampling at annual and 12/year resolution, files clipperton.4B.iso.txt and...

  3. Stomach nematodes (Mastophorus Muris) in rats (Rattus rattus) are associated with coconut (Cocos nucifera) Habitat at palmyra atoll

    Science.gov (United States)

    Lafferty, K.D.; Hathaway, S.A.; Wegmann, A.S.; Shipley, F.S.; Backlin, A.R.; Helm, J.; Fisher, R.N.

    2010-01-01

    Black rats (Rattus rattus) and their stomach nematodes (Mastophorus muris) were historically introduced to islets at Palmyra Atoll in the central Pacific Line Islands. To investigate patterns of parasitism, we trapped rats and quantified nematodes on 13 islets of various sizes and habitat types. Most rats were parasitized (59) with an average of 12 worms per infected rat. Islet size did not greatly influence parasite population biology. Nematodes also did not appear to affect rat condition (weight to skull length). The only strong and consistent factor associated with the mean abundance of nematodes in rats was habitat (dominant cover and locally dominant plant species). Thus, nematodes were much more abundant in rats from sites dominated by coconut trees (Cocos nucifera). Coconut trees may also be an introduced species at Palmyra Atoll. ?? American Society of Parasitologists 2010.

  4. Effects of Land-Use Change and Managed Aquifer Recharge on Geochemical Reactions with Implications for Groundwater Quantity and Quality in Atoll Island Aquifers, Roi-Namur, Republic of the Marshall Islands

    Science.gov (United States)

    Hejazian, M.; Swarzenski, P. W.; Gurdak, J. J.; Odigie, K. O.; Storlazzi, C. D.

    2015-12-01

    This study compares the hydrogeochemistry of two contrasting atoll groundwater systems in Roi-Namur, Republic of the Marshall Islands. Roi-Namur houses a U.S. Department of Defense military installation and presents an ideal study location where a human impacted aquifer is co-located next to a natural aquifer as part of two artificially conjoined atoll islands. The hydrogeology and geochemistry of carbonate atoll aquifers has been well studied, particularly because of its small, well-defined hydrologic system that allows for relatively precise modeling. However, it is unknown how changes in land-use/land cover and managed aquifer recharge (MAR) alters natural geochemical processes in atoll aquifers. A better understanding of this has implications on groundwater quantity and quality, carbonate dissolution, and best aquifer management practices in the context of rising sea level and saltwater intrusion. Roi has been heavily modified to house military and civilian operations; here, lack of vegetation and managed recharge has increased the volume of potable groundwater and affected the geochemical processes in the freshwater lens and saltwater transition zone. Namur is heavily vegetated and the hydrogeology is indicative of a natural atoll island. A suite of monitoring wells were sampled across both island settings for major ions, nutrients, trace elements, DOC/DIC, δ13C and δ18O/2H isotopes. By modeling geochemical reactions using a conservative mixing approach, we measure deviations from expected reactions and compare the two contrasting settings using derived geochemical profiles through a wide salinity spectrum. Results indicate that groundwater on Namur is more heavily depleted in δ13C and has greater dissolved inorganic carbon, suggesting higher microbial oxidation and greater dissolution within the carbonate aquifer. This suggests MAR and reduction of vegetation makes the groundwater supply on atoll islands more resilient to sea level rise.

  5. CRED 20m Gridded bathymetry and IKONOS estimated depths of Pearl and Hermes Atoll, Hawaii, USA (Arc ASCII format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry and IKONOS estimated depths of the shelf and slope environments of Pearl and Hermes Atoll, Hawaii, USA. Bottom coverage was achieved in depths...

  6. CRED 5 m Gridded bathymetry and IKONOS estimated depths of Pearl and Hermes Atoll, Hawaii, USA (Arc ASCII format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry and IKONOS estimated depths of the shelf and slope environments of Pearl and Hermes Atoll, Hawaii, USA. Bottom coverage was achieved in depths...

  7. CRED 20 m Gridded bathymetry and IKONOS estimated depths of Pearl and Hermes Atoll, Hawaii, USA (NetCDF format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry and IKONOS estimated depths of the shelf and slope environments of Pearl and Hermes Atoll, Hawaii, USA. Bottom coverage was achieved in depths...

  8. CRED 5 m Gridded bathymetry and IKONOS estimated depths of Pearl and Hermes Atoll, Hawaii, USA (NetCDF format)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Gridded bathymetry and IKONOS estimated depths of the shelf and slope environments of Pearl and Hermes Atoll, Hawaii, USA. Bottom coverage was achieved in depths...

  9. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 4. Releases to the biosphere of radionuclides from underground nuclear weapon tests at the atolls

    International Nuclear Information System (INIS)

    1998-08-01

    This report is Volume 4 in the series of 6 volumes of the Technical Report on the radiological situation at the atolls of Mururoa and the Fangataufa. It is the second of the three volumes dealing with the evaluation of the long term radiological situation as a consequence of radionuclide migration from underground sources, which is the responsibility of Task Group B. This volume is based on the activities of Working Group 4 and uses, as its primary input on radionuclide inventories the report of Working Group 3, which is Vol. 3 in this series of Technical Report. Nuclear testing in the atmosphere, outer space and under open ocean was prohibited by the Limited Test Ban Treaty of 5 August 1963 and signed by UK, USA and USSR. France ceased atmospheric testing in September 1974. Isolation from the biosphere in geological formations, or containment in geological formations, became the preferred alternative. The explosion of 137 underground nuclear devices in Mururoa and Fangataufa over the testing period 1975-1996, together with 10 safety trials and the burial of radioactively contaminated material gathered from the atoll surfaces, has resulted in a substantial accumulation of radionuclides in the rock beneath the two atolls. Assessment of the rate at which these radionuclides move from the cavities to the environment accessible to humans, or biosphere and the total radionuclide release to the biosphere over time is the central effort of this Study. The rock mass within which the radionuclides are initially deposited, and which serves to contain or delay release of the radionuclides, will be referred to as the geosphere to distinguish it from the biosphere, where the radionuclides would be accessible either directly or through the food chain to the living environment. This assessment of geosphere transport has been divided into the following four interrelated tasks: (a) Geological Pathways; (b) Hydrological Modelling; (c) Solution Source Term; and (d) Geosphere

  10. An investigation into the prevalence of thyroid disease on Kwajalein Atoll, Marshall Islands.

    Science.gov (United States)

    Takahashi, T; Trott, K R; Fujimori, K; Simon, S L; Ohtomo, H; Nakashima, N; Takaya, K; Kimura, N; Satomi, S; Schoemaker, M J

    1997-07-01

    The prevalence of thyroid nodules and thyroid cancer was studied in the indigenous population residing on Ebeye Island, Kwajalein Atoll, in the Republic of the Marshall Islands. This island, centrally located in the nation, is home to about 25% of the nation's population, many who have migrated there from other atolls. The objective of the study was to obtain thyroid disease rate statistics on as much of the population as possible that was alive during the years of nuclear testing and to test the hypothesis that described a linearly decreasing prevalence of palpable nodules with increasing distance from the Bikini test site. 1,322 Marshallese born before 1965 were given a thyroid examination using neck palpation, fine needle aspiration biopsy, and high resolution ultrasound imaging. Approximately 40% of the total population living on this island who are at risk from exposure to radioactive fallout during the years 1946-1958 were screened. Of that group, 815 were alive at the time of the BRAVO test on 1 March 1954. Two hundred sixty-six people with thyroid nodules were found (32.6%): 132 were palpable nodules (16.2%), and 134 were nodules that could be diagnosed with ultrasound only (15.7%). Prevalence of palpable nodules was particularly high in men and women older than 60 y, in men who were 6 to 15 y of age at the time of the BRAVO test, and in women 1 to 10 y of age at the time of the BRAVO test. In 22 people, the clinical diagnosis was most likely cancer though histopathological evidence was only available from 11 operated cases. Of the 11 operated cases, 10 were cancer. Cancer prevalence was particularly high in those women born between 1944 and 1953 (7/220 = 3.2%), i.e., who were children during the early years of nuclear testing. The Ebeye data showed a marginally significant correlation between palpable nodule prevalence among women and distance to Bikini (r = -0.44, p = 0.06). This report summarizes the clinical findings of the thyroid examinations, the age

  11. Behavior of plutonium isotopes in the marine environment of Enewetak atoll

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Robison, W.L.; Eagle, R.J.

    1998-01-01

    There continue to be reports in the literature that suggest a difference in the behavior of 239+240 Pu and 238 Pu in some aquatic environments. Plutonium isotopes have been measured in marine samples collected over 3 decades form Enewetak atoll, one of the sites in the Marshall Islands used by the United States between 1946 and 1958 to test nuclear devices. The plutonium isotopes originated from a variety of complex sources and could possibly coexist in this environment as different physical-chemical species. However results indicate little difference in the mobility and biological availability of 239+240 Pu and 238 Pu. (author)

  12. Exploring Mosquito Fauna of Majuro Atoll (Republic of Marshall Islands) in the Context of Zika Outbreak.

    Science.gov (United States)

    Marie, Jérôme; Perera, Devika; Garstang, Helentina; Bossin, Herve C; Bourtzis, Kostas

    2018-04-09

    First autochthonous Zika clinical case was reported in the Republic of Marshall Islands (RMI) on Majuro Atoll in February 2016. An entomological survey of mosquito larvae and adult populations was carried out in four areas of Majuro, the most populated atoll of RMI encompassing different habitats (forest, rural, or urban) including some with confirmed clinical Zika cases to evaluate which mosquito species could be involved in the Zika transmission. A total of 2,367 immature and adult mosquito specimens were collected and identified to the species level. In total, five mosquito species were detected, Aedes aegypti (Linnaeus), Aedes albopictus (Skuse), Aedes marshallensis (Stone and Bohart), Culex quinquefasciatus (Say), and Culex annulirostris (Skuse) (Diptera: Culicidae), a first record for RMI. The most abundant species was Ae. aegypti presumed to be the main vector of Zika virus followed by Ae. albopictus. Improved management of breeding containers through better public awareness and community engagement, mosquito surveillance and innovative mosquito control strategies using the sterile insect technique (SIT) and/or the incompatible insect technique (IIT) could help prevent outbreaks of arboviruses in the RMI.

  13. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

    Energy Technology Data Exchange (ETDEWEB)

    McMurtry, G.M.; Schneider, R.C. (Hawaii Univ., Honolulu (USA). Hawaii Inst. of Geophysics); Colin, P.L. (Hawaii Inst. of Marine Biology, Honolulu (USA)); Buddemeier, R.W. (California Univ., Livermore (USA). Lawrence Livermore Lab.); Suchanek, T.H. (Fairleigh Dickinson Univ., St. Croix, Virgin Islands (USA). West Indies Lab.)

    1985-02-21

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  14. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation

    International Nuclear Information System (INIS)

    McMurtry, G.M.; Schneider, R.C.; Buddemeier, R.W.; Suchanek, T.H.

    1985-01-01

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. The authors report elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon. (author)

  15. Radiochemical analysis of radio-nuclides in sea water collected near Bikini Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Miyake, Y; Sugiura, Y

    1955-01-01

    A radiochemical analysis of sea water containing fission materials collected near Bikini Atoll in June, 1954, was performed. The sea water was boiled with hydrochloric acid, iron and lanthanum salts each 5 mg as Fe and La were added to it. They were precipitated as hydroxide, which was dissolved in hydrochloric acid and ferric chloride was extracted with ethyl ether. The remaining solution was evaporated to dryness and the residue was dissolved in hydrochloric acid. Using the latter solution the group separation was done with cation exchanger resins.

  16. Limited trophic partitioning among sympatric delphinids off a tropical oceanic atoll.

    Directory of Open Access Journals (Sweden)

    Hillary Young

    Full Text Available Understanding trophic relationships among marine predators in remote environments is challenging, but it is critical to understand community structure and dynamics. In this study, we used stable isotope analysis of skin biopsies to compare the isotopic, and thus, trophic niches of three sympatric delphinids in the waters surrounding Palmyra Atoll, in the Central Tropical Pacific: the melon-headed whale (Peponocephala electra, Gray's spinner dolphin (Stenella longirostris longirostris, and the common bottlenose dolphin (Tursiops truncatus. δ15N values suggested that T. truncatus occupied a significantly higher trophic position than the other two species. δ13C values did not significantly differ between the three delphinds, potentially indicating no spatial partitioning in depth or distance from shore in foraging among species. The dietary niche area-determined by isotopic variance among individuals-of T. truncatus was also over 30% smaller than those of the other species taken at the same place, indicating higher population specialization or lower interindividual variation. For P. electra only, there was some support for intraspecific variation in foraging ecology across years, highlighting the need for temporal information in studying dietary niche. Cumulatively, isotopic evidence revealed surprisingly little evidence for trophic niche partitioning in the delphinid community of Palmyra Atoll compared to other studies. However, resource partitioning may happen via other behavioral mechanisms, or prey abundance or availability may be adequate to allow these three species to coexist without any such partitioning. It is also possible that isotopic signatures are inadequate to detect trophic partitioning in this environment, possibly because isotopes of prey are highly variable or insufficiently resolved to allow for differentiation.

  17. Land-use change and managed aquifer recharge effects on the hydrogeochemistry of two contrasting atoll island aquifers, Roi-Namur Island, Republic of the Marshall Islands

    International Nuclear Information System (INIS)

    Hejazian, Mehrdad; Gurdak, Jason J.; Swarzenski, Peter; Odigie, Kingsley O.; Storlazzi, Curt D.

    2017-01-01

    Freshwater resources on low-lying atoll islands are highly vulnerable to climate change and sea-level rise. In addition to rainwater catchment, groundwater in the freshwater lens is a critically important water resource on many atoll islands, especially during drought. Although many atolls have high annual rainfall rates, dense natural vegetation and high evapotranspiration rates can limit recharge to the freshwater lens. Here we evaluate the effects of land-use/land-cover change and managed aquifer recharge on the hydrogeochemistry and supply of groundwater on Roi-Namur Island, Republic of the Marshall Islands. Roi-Namur is an artificially conjoined island that has similar hydrogeology on the Roi and Namur lobes, but has contrasting land-use/land-cover and managed aquifer recharge only on Roi. Vegetation removal and managed aquifer recharge operations have resulted in an estimated 8.6 × 10"5 m"3 of potable groundwater in the freshwater lens on Roi, compared to only 1.6 × 10"4 m"3 on Namur. We use groundwater samples from a suite of 33 vertically nested monitoring wells, statistical testing, and geochemical modeling using PHREEQC to show that the differences in land-use/land-cover and managed aquifer recharge on Roi and Namur have a statistically significant effect on several groundwater-quality parameters and the controlling geochemical processes. Results also indicate a six-fold reduction in the dissolution of carbonate rock in the freshwater lens and overlying vadose zone of Roi compared to Namur. Mixing of seawater and the freshwater lens is a more dominant hydrogeochemical process on Roi because of the greater recharge and flushing of the aquifer with freshwater as compared to Namur. In contrast, equilibrium processes and dissolution-precipitation non-equilibrium reactions are more dominant on Namur because of the longer residence times relative to the rate of geochemical reactions. Findings from Roi-Namur Island support selective land

  18. Larval dispersal modeling of pearl oyster Pinctada margaritifera following realistic environmental and biological forcing in Ahe atoll lagoon.

    Directory of Open Access Journals (Sweden)

    Yoann Thomas

    Full Text Available Studying the larval dispersal of bottom-dwelling species is necessary to understand their population dynamics and optimize their management. The black-lip pearl oyster (Pinctada margaritifera is cultured extensively to produce black pearls, especially in French Polynesia's atoll lagoons. This aquaculture relies on spat collection, a process that can be optimized by understanding which factors influence larval dispersal. Here, we investigate the sensitivity of P. margaritifera larval dispersal kernel to both physical and biological factors in the lagoon of Ahe atoll. Specifically, using a validated 3D larval dispersal model, the variability of lagoon-scale connectivity is investigated against wind forcing, depth and location of larval release, destination location, vertical swimming behavior and pelagic larval duration (PLD factors. The potential connectivity was spatially weighted according to both the natural and cultivated broodstock densities to provide a realistic view of connectivity. We found that the mean pattern of potential connectivity was driven by the southwest and northeast main barotropic circulation structures, with high retention levels in both. Destination locations, spawning sites and PLD were the main drivers of potential connectivity, explaining respectively 26%, 59% and 5% of the variance. Differences between potential and realistic connectivity showed the significant contribution of the pearl oyster broodstock location to its own dynamics. Realistic connectivity showed larger larval supply in the western destination locations, which are preferentially used by farmers for spat collection. In addition, larval supply in the same sectors was enhanced during summer wind conditions. These results provide new cues to understanding the dynamics of bottom-dwelling populations in atoll lagoons, and show how to take advantage of numerical models for pearl oyster management.

  19. Distribution, sources and risk assessment of polychlorinated biphenyls in soils from the Midway Atoll, North Pacific Ocean.

    Directory of Open Access Journals (Sweden)

    Jing Ge

    Full Text Available Concentrations of 28 polychlorinated biphenyls (PCBs were assessed in soils from the Midway Atoll in the central North Pacific Ocean. The analytical procedure involved the application of accelerated solvent extraction (ASE and gas chromatography coupled with ion trap mass spectrometric detection (GC/ITMS for identification and quantification. Among the 28 PCB congeners studied, 26 of them, except CB195 and CB209, were detected in the analyzed samples at different frequencies. The total concentrations of 28 indicator PCBs (ΣPCBs ranged from 2.6 to 148.8 ng g⁻¹ with an average value of 50.7 ng g⁻¹ and median of 39.5 ng g⁻¹. Sources and congeners' pattern of PCB were investigated in the soil of Midway Atoll. The principal component analysis indicated that the compositions of PCBs in most of the soil samples were similar. The total concentrations of PCBs were used to assess the cancer risk probabilities in humans via ingestion, dermal contact and inhalation of soil particles. Very low cancer risk was found in all soil samples caused by ΣPCBs.

  20. 1996 Inventory of Endangered Species and Wildlife Resources on US Army Kwajalein Atoll, Republic of the Marshall Islands (NODC Accession 0000251)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report summarizes the results of the first United States Army Kwajalein Atoll (USAKA) Activities in the Republic of the Marshall Islands (UES) inventory of...

  1. Technical Basis Document: A Statistical Basis for Interpreting Urinary Excretion of Plutonium Based on Accelerator Mass Spectrometry (AMS) for Selected Atoll Populations in the Marshall Islands

    International Nuclear Information System (INIS)

    Bogen, K; Hamilton, T F; Brown, T A; Martinelli, R E; Marchetti, A A; Kehl, S R; Langston, R G

    2007-01-01

    We have developed refined statistical and modeling techniques to assess low-level uptake and urinary excretion of plutonium from different population group in the northern Marshall Islands. Urinary excretion rates of plutonium from the resident population on Enewetak Atoll and from resettlement workers living on Rongelap Atoll range from 239 Pu. However, our statistical analyses show that urinary excretion of plutonium-239 ( 239 Pu) from both cohort groups is significantly positively associated with volunteer age, especially for the resident population living on Enewetak Atoll. Urinary excretion of 239 Pu from the Enewetak cohort was also found to be positively associated with estimates of cumulative exposure to worldwide fallout. Consequently, the age-related trends in urinary excretion of plutonium from Marshallese populations can be described by either a long-term component from residual systemic burdens acquired from previous exposures to worldwide fallout or a prompt (and eventual long-term) component acquired from low-level systemic intakes of plutonium associated with resettlement of the northern Marshall Islands, or some combination of both

  2. Bikini Atoll ionizing radiation survey - May 1985 - May 1986

    International Nuclear Information System (INIS)

    Shingleton, K.L.; Cate, J.L.; Trent, M.G.; Robison, W.L.

    1988-01-01

    Between 1946 and 1958, the United States conducted 23 nuclear tests at the Bikini Atoll in the Marshall Islands. The single largest detonation was the Bravo test, which resulted in extensive radioactive contamination of a number of islands and prevented the timely resettlement of the native population. Since 1958, many studies have been conducted to assess clean up options and the internal and external radiation doses the Bikinians would likely receive, should they resettle the islands. Although the external dose rates from β and γ radiation have been previously determined by aerial and ground measurement techniques, technical constraints limited the assessment of external β dose rates from the Cs-137 and Sr-90/Y-90 contamination on the islands. Now, because of the recent development of very thin thermoluminescent dosimeters (TLDs), these external β dose rates can be measured

  3. The atolls of Mururoa and Fangataufa (French Polynesia). The nuclear testings. Radiological aspects

    International Nuclear Information System (INIS)

    Martin, G.

    2007-01-01

    This report provides a review of the radiological measures implemented during the thirty year period of French nuclear tests in Polynesian atolls of Mururoa and Fangataufa. It presents full details of the practices deployed throughout these tests, including, in particular, aspects concerning radiological protection for the population and the environment. It contains all the scientific results and measurements of radioactivity performed during this period, providing concrete facts that can be used to assess the consequences these tests have had on the personnel involved, the population and the environment. (author)

  4. Investigation of the marine communities of Midway Harbor and adjacent lagoon, Midway Atoll, Northwest Hawaiian Islands in 1998 (NODC Accession 0001098)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A survey of the marine communities of Midway Atoll harbor and surrounding lagoon was conducted at 12 sites from September 5 to 9, 1998. The primary focus of these...

  5. 1998 Inventory of Endangered Species and Wildlife Resources at the US Army Kwajalein Atoll, Republic of the Marshall Islands (NODC Accession 0000631)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This report summarizes the results of the second United States Army Kwajalein Atoll (USAKA) Activities in the Republic of the Marshall Islands (UES) inventory of...

  6. CRED Reson 8101 multibeam backscatter data of Palmyra Atoll, Pacific Remote Island Areas, Central Pacific with 1 meter resolution in netCDF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the lagoon, shelf, and slope environments of Palmyra Atoll, Pacific Island Areas, Central Pacific....

  7. Inventory of endangered species and wildlife resources at the US Army Kwajalein Atoll, Republic of the Marshall Islands, 1988 (NODC Accession 0000631)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An inventory of endangered species and the wildlife resources at the US Army Kwajelein Atoll, Republic of the Marshall Island were conducted from 30 October 1998 to...

  8. The natural history of Caroline Atoll, Southern Line Islands. Part I. History, physiography, botany, and isle descriptions

    Science.gov (United States)

    Kepler, A.K.; Kepler, C.B.

    1994-01-01

    conclusion: Lushly wooded Caroline Atoll, with the majority of its 39 islets (399 ha of land) either in near-pristine condition or having recovered remarkably from past disturbance, is one of the least spoiled atolls in the Pacific. Uninhabited, it harbors plant ecosystems and breeding seabirds (Pt. II) of national and international importance. Its marine and terrestrial ecosystems are prime outdoor ecological laboratories for research on geological processes including ground water, sea level changes, the dynamics of motu formation, fish poisoning, and numerous facets of ecology including plant succession and Pisonia growth rates. Caroline boasts prime coral reefs thickly studded with Tridacna clams, substantial numbers of coconut crabs, breeding sites for green turtles, wintering grounds for shorebirds including the rare Bristle-thighed Curlew, ancient Tuamotuan marae, and a crystalline, unpolluted lagoon. The variety, abundance, and quality of its flora and fauna qualify it for status as an officially recognized international preserve (Pt. II, Sect. G). Efforts toward its conservation have thus far been unsuccessful: in 1992 it was leased to a private French businessman who is currently fishing the reefs for commercial profit, as well as disturbing seabird, turtle and coconut crab populations.

  9. Host tolerance, not symbiont tolerance, determines the distribution of coral species in relation to their environment at a Central Pacific atoll

    Science.gov (United States)

    Wicks, L. C.; Gardner, J. P. A.; Davy, S. K.

    2012-06-01

    Tolerance of environmental variables differs between corals and their dinoflagellate symbionts ( Symbiodinium spp.), controlling the holobiont's (host and symbiont combined) resilience to environmental stress. However, the ecological role that environmental variables play in holobiont distribution remains poorly understood. We compared the drivers of symbiont and coral species distributions at Palmyra Atoll, a location with a range of reef environments from low to high sediment concentrations (1-52 g dry weight m-2 day-1). We observed uniform holobiont partnerships across the atoll (e.g. Montipora spp. with Symbiodinium type C15 at all sites). Multivariate analysis revealed that field-based estimates of settling sediment predominantly explained the spatial variation of coral species among sites ( P coral rather than Symbiodinium physiology. The data highlight the importance of host tolerance to environmental stressors, which should be considered simultaneously with symbiont sensitivity when considering the impact of variations in environmental conditions on coral communities.

  10. Mapping elemental contamination on Palmyra Atoll National Wildlife Refuge

    Science.gov (United States)

    Struckhoff, Matthew A.; Orazio, Carl E.; Tillitt, Donald E.; Shaver, David K.; Papoulias, Diana M.

    2018-01-01

    Palmyra Atoll, once a WWII U.S. Navy air station, is now a U.S. National Wildlife Refuge with nearly 50 km2 of coral reef and 275 ha of emergent lands with forests of Pisonia grandistrees and colonies of several bird species. Due to the known elemental and organic contamination from chemicals associated with aviation, power generation and transmission, waste management, and other air station activities, a screening survey to map elemental concentrations was conducted. A map of 1944 Navy facilities was georeferenced and identifiable features were digitized. These data informed a targeted survey of 25 elements in soils and sediment at locations known or suspected to be contaminated, using a hand-held X-ray fluorescence spectrometer. At dozens of locations, concentrations of elements exceeded established soil and marine sediment thresholds for adverse ecological effects. Results were compiled into a publically available geospatial dataset to inform potential remediation and habitat restoration activities.

  11. Spectral evolution of the Atoll source 4U 1728-34 with RXTE and INTEGRAL: evidence for hard X-ray tail

    NARCIS (Netherlands)

    Tarana, A.; Belloni, T.; Bazzano, A.; Homan, J.; Méndez, M.; Ubertini, P.; Comastri, A.; Angelini, L.; Cappi, M.

    We report the temporal and spectral results on the INTEGRAL and RXTE 2006-2007 observation campaign of the Atoll source 4U 1728-34 (GX 354-0). The source shows, more than once, spectral evolution as revealed by the hardness intensity diagram. The soft state is well described by a Comptonization with

  12. Plastic ingestion by Masked booby, Sula dactylatra Lesson, 1831, on Biological Reserve of Rocas Atoll, RN, Brazil

    Directory of Open Access Journals (Sweden)

    Erich de Freitas Mariano

    2012-11-01

    Full Text Available Plastic particles are one of the most common pollutants in the marine environment and it is reaching regions with low human population density. These particles are frequently ingested by many marine organisms, causing digestive problems, which may lead to the weakening and death of the animal. In a research on the feeding of 631-masked boobies, Sula dactylatra from the Biological Reserve of Atol das Rocas, plastic particles were found in stomach contents of four adults. The artifacts found were made of transperant plastic, a piece of label of a mineral water bottle, two pieces of black plastic and a small hard and red piece. The flow of fishing and tourism boats on the Atol das Rocas Biological Reserve may be the source of origin of the plastic parts in both the stomach contents and those found on the islands of the reserve, which suggests that anthropogenic behaviour has already reached isolated areas which should have a high degree of biodiversity protection. Several measures can be taken to avoid deleterious events in the marine biota, but there is great difficulty in avoiding waste dumping from fishing and tourism ships/boats, in addition to that, there are many materials from the mainland, which requires an increase in awareness and supervision.

  13. Human impact on atolls leads to coral loss and community homogenisation: a modeling study.

    Directory of Open Access Journals (Sweden)

    Bernhard M Riegl

    Full Text Available We explore impacts on pristine atolls subjected to anthropogenic near-field (human habitation and far-field (climate and environmental change pressure. Using literature data of human impacts on reefs, we parameterize forecast models to evaluate trajectories in coral cover under impact scenarios that primarily act via recruitment and increased mortality of larger corals. From surveys across the Chagos, we investigate the regeneration dynamics of coral populations distant from human habitation after natural disturbances. Using a size-based mathematical model based on a time-series of coral community and population data from 1999-2006, we provide hind- and forecast data for coral population dynamics within lagoons and on ocean-facing reefs verified against monitoring from 1979-2009. Environmental data (currents, temperatures were used for calibration. The coral community was simplified into growth typologies: branching and encrusting, arboresent and massive corals. Community patterns observed in the field were influenced by bleaching-related mortality, most notably in 1998. Survival had been highest in deep lagoonal settings, which suggests a refuge. Recruitment levels were higher in lagoons than on ocean-facing reefs. When adding stress by direct human pressure, climate and environmental change as increased disturbance frequency and modified recruitment and mortality levels (due to eutrophication, overfishing, pollution, heat, acidification, etc, models suggest steep declines in coral populations and loss of community diversification among habitats. We found it likely that degradation of lagoonal coral populations would impact regeneration potential of all coral populations, also on ocean-facing reefs, thus decreasing reef resilience on the entire atoll.

  14. Weights, hematology and serum chemistry of free-ranging brown boobies (Sula leucogaster) in Johnston Atoll, Central Pacific

    Science.gov (United States)

    Work, Thierry M.

    1999-01-01

    Hematologic and serum chemistry values are reported for 105 brown boobies (Sula leucogaster) from Johnston Atoll, Central Pacific. Hematocrit, estimated total plasma solids, total and differential white cell counts, serum glucose, calcium, phosphorus, uric acid, total protein, albumin, globulin, aspartate aminotransferase, and creatinine phosphokinase were analyzed. Hematologic and serum chemistry values varied with age and sex. Values were compared with those of red-footed boobies and other tropical and temperate marine pelecaniforms.

  15. Frequency distribution, isotopic composition and physical characterization of plutonium-bearing particles from the Fig-Quince zone on Runit Island, Enewetak Atoll

    DEFF Research Database (Denmark)

    Hamilton, Terry F.; Jernström, Jussi; Martinelli, Roger E.

    2009-01-01

    Runit Island on Enewetak Atoll was very heavily impacted by the U.S. nuclear testing campaign in the northern Marshall Islands (1946–58). The primary source of contamination on Runit Island was the 1958 Quince safety test where a large quantity of device plutonium (Pu) was scattered over the area...

  16. Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Jokela, T.A.; Brunk, J.A.

    1986-07-01

    This report summarizes all available data on the concentrations of radionuclides in fish from Bikini Atoll between 1977 and 1984. As found in other global studies, 137 Cs is most highly accumulated in edible flesh of all species of fish, the lowest fractions are found in the bone or liver. The mean concentration of 137 Cs in muscle of reef fish from the southern part of the atoll is comparable to the global fallout concentration measured in market samples of fish collected from Chicago, Illinois, in 1982. 90 Sr is generally associated with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of 60 Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of 60 Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of 207 Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of 207 Bi were consistently detected in the muscle (and other tissues) of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, surgeonfish, and parrotfish, 207 Bi was usually below detection limits by gamma spectrometry. Over 70% of the whole-body activity of 207 Bi in goatfish is associated with the muscle tissue, whereas less than 5% is found in the muscle of mullet and surgeonfish. Neither 239+240 Pu nor 241 Am is significantly accumulated in the muscle tissue of any species of fish. Apparently, 238 Pu is in a more readily available form for accumulation by fishes than 239+240 Pu. Based on a daily ingestion rate of 200 q of fish flesh, dose rates to individuals through the fish-food ingestion pathway are well below current Federal guidelines

  17. An updated dose assessment for a U.S. Nuclear Test Site - Bikini Atoll

    International Nuclear Information System (INIS)

    Robison, W.L.; Bogen, K.T.; Conrado, C.L.

    1995-10-01

    On March 1, 1954, a nuclear weapon test, code-named BRAVO, conducted at Bikini Atoll in the northern Marshall Islands contaminated the major residence island. There has been a continuing effort since 1977 to refine dose assessments for resettlement options at Bikini Atoll. Here we provide a radiological dose assessment for the main residence island, Bikini, using extensive radionuclide concentration data derived from analysis of food crops, ground water, cistern water, fish and other marine species, animals, air, and soil collected at Bikini Island as part of our continuing research and monitoring program that began in 1975. The unique composition of coral soil greatly alters the relative contribution of cesium-137 ( 137 Cs) and strontium-90 ( 90 Sr) to the total estimated dose relative to expectations based on North American and European soils. Without counter measures, cesium-137 produces 96% of the estimated dose for returning residents, mostly through uptake from the soil to terrestrial food crops but also from external gamma exposure. The doses are calculated assuming a resettlement date of 1999. The estimated maximum annual effective dose for current island conditions is 4.0 mSv when imported foods, which are now an established part of the diet, are available. The corresponding 30-, 50-, and 70-y integral effective doses are 9.1 cSv, 13 cSv, and 15 cSv, respectively. A corresponding uncertainty analysis showed that after about 5 y of residence, the 95% confidence limits on population-average dose would be ±35% of its expected value. We have evaluated various countermeasures to reduce 137 Cs in food crops. Treatment with potassium reduces the uptake of 137 Cs into food crops, and therefore the ingestion dose, to about 5% of pretreatment levels and has essentially no negative environmental consequences

  18. Some statistical aspects of the cleanup of Enewetak Atoll

    International Nuclear Information System (INIS)

    Barnes, M.G.; Giacomini, J.J.; Friesen, H.N.

    1979-01-01

    Cleaning up the radionuclide contamination at Enewetak Atoll has involved a number of statistical design problems. Theoretical considerations led to choosing a grid sampling pattern; practical problems sometimes lead to resampling on a finer grid. Other problems associated with using grids have been both physical and statistical. The standard sampling system is an in situ intrinsic gamma detector which measures americium concentration. The cleanup guidelines include plutonium concentration, so additional sampling of soil is required to establish Pu/Am ratios. The soil sampling design included both guidelines for location of the samples and also a special pattern of subsamples making up composite samples. The large variance of the soil, sample results makes comparison between the two types difficult anyway, but this is compounded by vegetation attenuation of the in situ readings, soil disturbance influences, and differences in devegetation methods. The constraints inherent in doing what amounts to a research and development project, on a limited budget of time and money, in a field engineering environment are also considered

  19. Impacts of category 5 tropical cyclone Fantala (April 2016) on Farquhar Atoll, Seychelles Islands, Indian Ocean

    Science.gov (United States)

    Duvat, Virginie K. E.; Volto, Natacha; Salmon, Camille

    2017-12-01

    This paper provides new insights on the impacts of a category 5 tropical cyclone on Indian Ocean atoll reef islands. Using multi-date aerial imagery and field observations, the contribution of tropical cyclone Fantala to shoreline and island change, and to sediment production and transport, was assessed on Farquhar Atoll, Seychelles Islands. Results show that the two largest islands (> 3 km2) only suffered limited land loss (- 1.19 to - 8.35%) while small islets lost 13.17 to 28.45% of their initial land area. Islands and islets exhibited contrasting responses depending on their location, topography and vegetation type. Depending on islands, the retreat of the vegetation line occurred either along all shorelines, or along ocean shoreline only. The structure (wooded vs. grassy) and origin (native vs. introduced) of the vegetation played a major role in island response. Five days after the cyclone, beach width and beach area were multiplied by 1.5 to 10, depending on the setting, and were interpreted as resulting from both sediment reworking and the supply of large amounts of fresh sediments by the reef outer slopes to the island system. Fourth months after the cyclone, extended sheets of loose sediments were still present on the reef flat and in inter-islet channels and shallow lagoon waters, indicating continuing sediment transfer to islands. As a reminder (see Section 3.1.4), beach width uncertainty equals to 6 m for all beach sections.

  20. Resuspension studies at Bikini Atoll

    International Nuclear Information System (INIS)

    Shinn, J.H.; Homan, D.N.; Robison, W.L.

    1980-02-01

    The following experiments were conducted on Bikini Atoll to provide key parameters for an assessment of inhalation exposure from plutonium-contaminated dust aerosols: (1) a characterization of background (plutonium activity, dust, plutonium, sea spray, and organic aerosol concentrations); (2) a study of plutonium resuspension from a bare field; (3) a study of plutonium resuspension by traffic; and (4) a study of personal inhalation exposure. Dust concentrations of 21 μg m -3 and sea spray of 34 μg m -3 were the background throughout the Bikini Island except within 50 m of the windward beach. Background concentrations of 239+240 Pu were 60 aCi m -3 in the coconut grove and 264 aCi m -3 over rain-stabilized bare soil. The ratio of plutonium activity in aerosols relative to the activity in underlying soil, defined as the enhancement factor, EF, was typically less than one. Enhancement factors increased about 3.8 as a result of tilling. Plutonium resuspension flux was estimated at 0.49 pCi m -2 year -1 over most of Bikini Island. Aerosol size distributions associated with mass and with plutonium activity were typically log-normal with median aerodynamic diameter 2.44 μm, which decreased to 2.0 μm above freshly tilled soil. The Pu concentration in aerosols collected over disturbed soil increased by a factor of 19.1. Vehicular traffic produced dust pulses typically of 10 s duration, 28 μg m -3 average concentration, and plutonium enhancement factor 2.5. Personal dosimetry showed that enhancement of dust by a worker was a factor of 2.64 for heavy work outdoors and 1.86 for light work in and around houses. Pulmonary deposition of plutonium was calculated for various exposure conditions. The pulmonary deposition ranged from 1476 aCi h -1 to 12 aCi h -1

  1. Updated radiological dose assessment of Bikini and Eneu Islands at Bikini Atoll

    International Nuclear Information System (INIS)

    Robison, W.L.; Mount, M.E.; Phillips, W.A.; Stuart, M.L.; Thompson, S.E.; Conrado, C.L.; Stoker, A.C.

    1982-01-01

    This report is part of a continuing effort to refine dose assessments for resettlement options at Bikini Atoll. Radionuclide concentration data developed at Bikini Atoll since 1977 have been used in conjunction with recent dietary information and current dose models to develop the annual dose rate and 30- and 50-y integral doses presented here for Bikini and Eneu Island living patterns. The terrestrial food chain is the most significant exposure pathway--it contributes more than 50% of the total dose--and external gamma exposure is the second most significant pathway. Other pathways evaluated are the marine food chain, drinking water, and inhalation. Cesium-137 produces more than 85% of the predicted dose; 90 Sr is the second most significant radionuclide; 60 Co contributes to the external gamma exposure in varying degrees, but is a small part of the total predicted dose; the transuranic radionuclides contribute a small portion of the total predicted lung and bone doses but do present a long-term source of exposure. Maximum annual dose rates for Bikini Island are about 1 rem/y for the whole body and bone marrow when imported foods are available and about 1.9 rem/y when imports are unavailable. Maximum annual dose rates for Eneu Island when imports are available are 130 mrem/y for the whole body and 136 mrem/y for bone marrow. Similar doses when imported foods are unavailable are 245 and 263 mrem/y, respectively. The 30-y integral doses for Bikini Island are about 23 rem for whole body and bone marrow when imported foods are available and more than 40 rem when imports are unavailable. The Eneu Island 30-y integral doses for whole body and bone marrow are about 3 rem when imports are available and 5.5 and 6.1 rem, respectively, when imports are unavailable. Doses from living patterns involving some combination of Bikini and Eneu Islands fall between the doses listed above for each island separately

  2. Assessment of coastal erosion and quantification of land loss on Western Pacific atolls during the last 50 years

    Science.gov (United States)

    Taborosi, Danko; Zega, Mojca; Jenson, John W.

    2010-05-01

    The majority of islands in the tropical western Pacific are coral atolls. Most are inhabited by indigenous Micronesian populations. Local people have over the millennia developed coping strategies and response mechanisms to difficult natural conditions, including typhoons, erosion, giant swells, and flooding, as well as ensuing famines and epidemics. However, since 1990s residents of atolls in the region have been appealing for help. They indicate that their islands are being rapidly eroded along coastlines, land areas are becoming smaller, and taro patches and other vegetation are being damaged. Such concerns were corroborated by one sweeping assessment by South Pacific Applied Geoscience Commission in 1998, as well as various isolated field observations since. Evidence of recent coastal erosion is found locally on many islands, both on windward and leeward sides and ocean and lagoon facing shores. Examples include retreating modern beaches, exhumed beachrock, scouring and undercutting of vegetation, overhanging scarps, etc. In addition, a considerable number of uninhabited islets have been completely obliterated by storms in the recent past; unusually high tides and swells have swept over large populated islands, destroying homes and harming agriculture; and at least one atoll has been abandoned due to irrecoverable typhoon damage. Those problems have received much worldwide media coverage, in which they are generally presented as "sinking" of islands due to global climate change and accompanying sea level rise. In reality, modern atolls are now known to be artifacts of the Pacific mid-Holocene High-Stand, and no first-hand data are available from Pacific islands to discern what proportion of observed erosional phenomena are 1) due to local natural and anthropogenic coastal processes as opposed to global and regional changes, and 2) caused by continuous natural dynamics as opposed to episodic extreme events. It is clear that some islands are faring better than

  3. An improved method for removing transuranics from coral soil at Johnston Atoll

    International Nuclear Information System (INIS)

    Moroney, J.D. III.; Johnson, N.R.; Moroney, K.S.; Mercier, J.R.

    1992-01-01

    An improved approach for removing mixed plutonium and americium contamination from coral soil matrix at the Defense Nuclear Agency's (DNA's) Johnston Atoll site has been developed by DNA's contractor, TMA/Eberline. The system uses arrays of sensitive radiation detectors coupled with sophisticated computer software newly designed by Eberline Instrument Corporation. The software controls a unique segmented gate methodology for removing contaminated soil from a moving feed supply on conveyor belts. Contaminated soil is diverted to a metal drum for collecting larger sized 'hot' particles (< 5,000 Becquerels) or to a soil washing process designed to remove dispersed low level contamination from a soil fraction consisting of very small particles. Low to intermediate levels of contamination are removed from the soil to meet DNAs criteria for release for unrestricted use based on US EPA guidelines

  4. Redistribution of fallout radionuclides in Enewetak Atoll lagoon sediments by callianassid bioturbation.

    Science.gov (United States)

    McMurtry, G M; Schneider, R C; Colin, P L; Buddemeier, R W; Suchanek, T H

    The lagoon sediments of Enewetak Atoll in the Marshall Islands contain a large selection of fallout radionuclides as a result of 43 nuclear weapon tests conducted there between 1948 and 1958. Studies of the burial of fallout radionuclides have been conducted on the islands and in several of the large craters, but studies of their vertical distribution have been limited to about the upper 20 cm of the lagoon sediments. We have found elevated fallout radionuclide concentrations buried more deeply in the lagoon sediments and evidence of burrowing into the sediment by several species of callianassid ghost shrimp (Crustacea: Thalassinidea) which has displaced highly radioactive sediment. The burrowing activities of callianassids, which are ubiquitous on the lagoon floor, facilitate radionuclide redistribution and complicate the fallout radionuclide inventory of the lagoon.

  5. Mapping nuclear craters on Enewetak Atoll, Marshall Islands

    Science.gov (United States)

    Hampson, John C., Jr.

    1986-01-01

    In 1984, the U.S. Geological Survey conducted a detailed geologic analysis of two nuclear test craters at Enewetak Atoll, Marshall Islands, on behalf of the Defense Nuclear Agency. A multidisciplinary task force mapped the morphology, surface character, and subsurface structure of two craters, OAK and KOA. The field mapping techniques include echo sounding, sidescan sonar imaging, single-channel and multichannel seismic reflection profiling, a seismic refraction survey, and scuba and submersible operations. All operations had to be navigated precisely and correlatable with subsequent drilling and sampling operations. Mapping with a high degree of precision at scales as large as 1:1500 required corrections that often are not considered in marine mapping. Corrections were applied to the bathymetric data for location of the echo- sounding transducer relative to the navigation transponder on the ship and for transducer depth, speed of sound, and tidal variations. Sidescan sonar, single-channel seismic reflection, and scuba and submersible data were correlated in depth and map position with the bathymetric data to provide a precise, internally consistent data set. The multichannel and refraction surveys were conducted independently but compared well with bathymetry. Examples drawn from processing the bathymetric, sidescan sonar, and single- channel reflection data help illustrate problems and procedures in precision mapping.

  6. Land-use change and managed aquifer recharge effects on the hydrogeochemistry of two contrasting atoll island aquifers, Roi-Namur Island, Republic of the Marshall Islands

    Science.gov (United States)

    Hejazian, Mehrdad; Gurdak, Jason J.; Swarzenski, Peter W.; Odigie, Kingsley; Storlazzi, Curt

    2017-01-01

    Freshwater resources on low-lying atoll islands are highly vulnerable to climate change and sea-level rise. In addition to rainwater catchment, groundwater in the freshwater lens is a critically important water resource on many atoll islands, especially during drought. Although many atolls have high annual rainfall rates, dense natural vegetation and high evapotranspiration rates can limit recharge to the freshwater lens. Here we evaluate the effects of land-use/land-cover change and managed aquifer recharge on the hydrogeochemistry and supply of groundwater on Roi-Namur Island, Republic of the Marshall Islands. Roi-Namur is an artificially conjoined island that has similar hydrogeology on the Roi and Namur lobes, but has contrasting land-use/land-cover and managed aquifer recharge only on Roi. Vegetation removal and managed aquifer recharge operations have resulted in an estimated 8.6 x 105 m3 of potable groundwater in the freshwater lens on Roi, compared to only 1.6 x 104 m3 on Namur. We use groundwater samples from a suite of 33 vertically nested monitoring wells, statistical testing, and geochemical modeling using PHREEQC to show that the differences in land-use/land-cover and managed aquifer recharge on Roi and Namur have a statistically significant effect on several groundwater-quality parameters and the controlling geochemical processes. Results also indicate a seven-fold reduction in the dissolution of carbonate rock in the freshwater lens and overlying vadose zone of Roi compared to Namur. Mixing of seawater and the freshwater lens is a more dominant hydrogeochemical process on Roi because of the greater recharge and flushing of the aquifer with freshwater as compared to Namur. In contrast, equilibrium processes and dissolution-precipitation non-equilibrium reactions are more dominant on Namur because of the longer residence times relative to the rate of geochemical reactions. Findings from Roi-Namur Island support selective land-use/land-cover change and

  7. Seafloor geomorphology and geology of the Kingman Reef-Palmyra Atoll region, Central Pacific Ocean

    Science.gov (United States)

    Eakins, Barry; Barth, Ginger; Scheirer, Dan; Mosher, Dave; Armstrong, Andy

    2017-04-01

    Kingman Reef and Palmyra Atoll are the exposed summits of two seamounts within the Line Islands Volcanic Chain in the Central Pacific Ocean. Both are U.S. Territories, and the Exclusive Economic Zone around the islands was partially surveyed in 1991 with GLORIA sidescan sonar and seismic reflection profiling. New multibeam swath sonar surveys were conducted in 2010, 2015, and 2016 around the islands, in support of U.S. Extended Continental Shelf investigations. Numerous transits through the region by research vessels have collected additional multibeam swath sonar data. We present new, detailed maps of bathymetry, sidescan sonar imagery, geology, and sediment isopachs of the seafloor surrounding the islands, and how these have informed our understanding of the islands' margins. The islands are the last subaerial remnants of a complex, horse-shoe-shaped volcanic platform spanning roughly 200 km in diameter. The elevated platform from which the seamounts arise comprises at least 10 individual volcanic centers that have heights exceeding 3000m above the nearby abyssal plains. Gravity modeling suggests that the elevated platform is compensated by thickened crust. Strong carbonate caps and voluminous sediment accumulations flanking the platform indicate that the volcanoes were once shallow-water or emergent systems. These systems produced vast quantities of carbonate sediment that were shed to a deep interior basin to the east of Palmyra Atoll, and to nearby abyssal plains. The identification of mass failures, sediment reworking and bedforms, and channel networks provide evidence for extensive sedimentary processes around these volcanic centers. Analysis of the seamounts atop the elevated platform and in the seamount province to the northwest shows that flat-topped seamounts ("guyots") are principally found at depths shallower than 1300 meters, while peaked seamounts are almost exclusively found at greater depths. This constrains the amount of regional subsidence that

  8. Independent verification of plutonium decontamination on Johnston Atoll (1992--1996)

    International Nuclear Information System (INIS)

    Wilson-Nichols, M.J.; Wilson, J.E.; McDowell-Boyer, L.M.; Davidson, J.R.; Egidi, P.V.; Coleman, R.L.

    1998-05-01

    The Field Command, Defense Special Weapons Agency (FCDSWA) (formerly FCDNA) contracted Oak Ridge National Laboratory (ORNL) Environmental Technology Section (ETS) to conduct an independent verification (IV) of the Johnston Atoll (JA) Plutonium Decontamination Project by an interagency agreement with the US Department of Energy in 1992. The main island is contaminated with the transuranic elements plutonium and americium, and soil decontamination activities have been ongoing since 1984. FCDSWA has selected a remedy that employs a system of sorting contaminated particles from the coral/soil matrix, allowing uncontaminated soil to be reused. The objective of IV is to evaluate the effectiveness of remedial action. The IV contractor's task is to determine whether the remedial action contractor has effectively reduced contamination to levels within established criteria and whether the supporting documentation describing the remedial action is adequate. ORNL conducted four interrelated tasks from 1992 through 1996 to accomplish the IV mission. This document is a compilation and summary of those activities, in addition to a comprehensive review of the history of the project

  9. Modeling patterns of coral bleaching at a remote Central Pacific atoll.

    Science.gov (United States)

    Williams, Gareth J; Knapp, Ingrid S; Maragos, James E; Davy, Simon K

    2010-09-01

    A mild bleaching event (9.2% prevalence) at Palmyra Atoll occurred in response to the 2009 ENSO, when mean water temperature reached 29.8-30.1 degrees C. Prevalence among both abundant and sparse taxa varied with no clear pattern in susceptibility relating to coral morphology. Seven taxon-specific models showed that turbidity exacerbated while prior exposure to higher background temperatures alleviated bleaching, with these predictors explaining an average 16.3% and 11.5% variation in prevalence patterns, respectively. Positive associations occurred between bleaching prevalence and both immediate temperature during the bleaching event (average 8.4% variation explained) and increased sand cover (average 3.7%). Despite these associations, mean unexplained variation in prevalence equalled 59%. Lower bleaching prevalence in areas experiencing higher background temperatures suggests acclimation to temperature stress among several coral genera, while WWII modifications may still be impacting the reefs via shoreline sediment re-distribution and increased turbidity, exacerbating coral bleaching susceptibility during periods of high temperature stress. Copyright 2010 Elsevier Ltd. All rights reserved.

  10. Concentrations of radionuclides in fish collected from Bikini Atoll between 1977 and 1984

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Jokela, T.A.; Brunk, J.A.

    1986-07-01

    This report summarizes all available data on the concentrations of radionuclides in fish from Bikini Atoll between 1977 and 1984. As found in other global studies, /sup 137/Cs is most highly accumulated in edible flesh of all species of fish, the lowest fractions are found in the bone or liver. The mean concentration of /sup 137/Cs in muscle of reef fish from the southern part of the atoll is comparable to the global fallout concentration measured in market samples of fish collected from Chicago, Illinois, in 1982. /sup 90/Sr is generally associated with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of /sup 60/Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of /sup 60/Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of /sup 207/Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of /sup 207/Bi were consistently detected in the muscle (and other tissues) of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, surgeonfish, and parrotfish, /sup 207/Bi was usually below detection limits by gamma spectrometry. Over 70% of the whole-body activity of /sup 207/Bi in goatfish is associated with the muscle tissue, whereas less than 5% is found in the muscle of mullet and surgeonfish. Neither /sup 239 +240/Pu nor /sup 241/Am is significantly accumulated in the muscle tissue of any species of fish. Apparently, /sup 238/Pu is in a more readily available form for accumulation by fishes than /sup 239 +240/Pu. Based on a daily ingestion rate of 200 q of fish flesh, dose rates to individuals through the fish-food ingestion pathway are well below current Federal guidelines.

  11. Clipperton Atoll (eastern Pacific): oceanography, geomorphology, reef-building coral ecology and biogeography

    Science.gov (United States)

    Glynn, P. W.; Veron, J. E. N.; Wellington, G. M.

    1996-06-01

    Coral reef geomorphology and community composition were investigated in the tropical northeastern Pacific during April 1994. Three areas were surveyed in the Revillagigedo Islands (Mexico), and an intensive study was conducted on Clipperton Atoll (1,300 km SW of Acapulco), including macro-scale surface circulation, sea surface temperature (SST) climatology, geomorphology, coral community structure, zonation, and biogeography. Satellite-tracked drifter buoys from 1979 1993 demonstrated complex patterns of surface circulation with dominantly easterly flow (North Equatorial Counter Current, NECC), but also westerly currents (South Equatorial Current, SEC) that could transport propagules to Clipperton from both central and eastern Pacific regions. The northernmost latitude reached by the NECC is not influenced by El Niño-Southern Oscillation (ENSO) events, but easterly flow velocity evidently is accelerated at such times. Maximum NECC flow rates indicate that the eastern Pacific barrier can be bridged in 60 to 120 days. SST anomalies at Clipperton occur during ENSO events and were greater at Clipperton in 1987 than during 1982 1983. Shallow (15 18 m)and deep (50 58 m) terraces are present around most of Clipperton, probably representing Modern and late Pleistocene sea level stands. Although Clipperton is a well developed atoll with high coral cover, the reef-building fauna is depauperate, consisting of only 7 species of scleractinian corals belonging to the genera Pocillopora, Porites, Pavona and Leptoseris, and 1 species of hydrocoral in the genus Millepora. The identities of the one Pocilpopora species and one of the two Porites species are still unknown. Two of the remaining scleractinians ( Pavona minuta, Leptoseris scabra) and the hydrocoral ( Millepora exaesa), all formerly known from central and western Pacific localities, represent new eastern Pacific records. Scleractinian corals predominate (10 100% cover) over insular shelf depths of 8 to 60m, and crustose

  12. Preliminary hard and soft bottom seafloor substrate map (40m grid) derived from an unsupervised classification of gridded backscatter and bathymetry derivatives at Rose Atoll, Territory of American Samoa, USA.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Preliminary hard and soft seafloor substrate map derived from an unsupervised classification of multibeam backscatter and bathymetry derivatives at Rose Atoll,...

  13. Radionuclide concentrations in underground waters of Mururoa and Fangataufa Atolls.

    Science.gov (United States)

    Mulsow, S; Coquery, M; Dovlete, C; Gastaud, J; Ikeuchi, Y; Pham, M K; Povinec, P P

    1999-09-30

    In 1997 an expedition to Mururoa and Fangataufa Atolls was carried out to sample underground waters from cavity-chimneys and carbonate monitoring wells. The aim of this study was to determine the prevailing concentration and distribution status of radionuclides. Elemental analysis of interstitial waters was carried out in the water fraction as well as in particles collected at 11 underground monitoring wells. 238Pu, 239,240Pu, 241Am, 137Cs, 90Sr, 3H, 125Sb, 155Eu and 60Co were analyzed in both fractions by alpha-, beta- and gamma-spectrometry. Measurements showed that at 60% of the sites, pH and Eh seemed to be related to tidal cycles; in contrast HTO was constant during the sampling time. Interstitial waters from carbonates and transition zones shared similar chemical composition that were not different from that of the surrounding seawater. Waters collected from basalt cavities left after nuclear tests, (Aristee and Ceto) have a different chemical signature characterized by a deficiency in Mg, K and SO4 as well as enrichment in Sr, Si, Al and Cl compared to the rest of the stations. Radionuclide concentrations present in both, water and particulate fractions, were significantly higher at Ceto and Aristee than at any other monitoring wells, except for Fuseau and Mitre monitoring wells (Fangataufa) where values similar to Ceto were found (e.g. 239,240Pu: > 20 mBq g-1). Considering that Pu isotopes showed high Kd values compared to non-sorbing radionuclides such as 3H, 90Sr and 137Cs it is very unlikely that migration from cavities to monitoring wells accounts for the concentration of Pu isotopes and Am at Fuseau 30 and Mitre 27. Perhaps the contact of lagoon waters with the well before sealing could be a possible source of the transuranics found at these sites. The 238Pu/239,240Pu ratios measured in the particles were similar to that of the lagoon (0.38), thus supporting this hypothesis. The fact that transuranics were found only in the particle fraction, in the

  14. The shark assemblage at French Frigate Shoals atoll, Hawai'i: species composition, abundance and habitat use.

    Science.gov (United States)

    Dale, Jonathan J; Stankus, Austin M; Burns, Michael S; Meyer, Carl G

    2011-02-10

    Empirical data on the abundance and habitat preferences of coral reef top predators are needed to evaluate their ecological impacts and guide management decisions. We used longline surveys to quantify the shark assemblage at French Frigate Shoals (FFS) atoll from May to August 2009. Fishing effort consisted of 189 longline sets totaling 6,862 hook hours of soak time. A total of 221 sharks from 7 species were captured, among which Galapagos (Carcharhinus galapagensis, 36.2%), gray reef (Carcharhinus amblyrhynchos, 25.8%) and tiger (Galeocerdo cuvier, 20.4%) sharks were numerically dominant. A lack of blacktip reef sharks (Carcharhinus melanopterus) distinguished the FFS shark assemblage from those at many other atolls in the Indo-Pacific. Compared to prior underwater visual survey estimates, longline methods more accurately represented species abundance and composition for the majority of shark species. Sharks were significantly less abundant in the shallow lagoon than adjacent habitats. Recaptures of Galapagos sharks provided the first empirical estimate of population size for any Galapagos shark population. The overall recapture rate was 5.4%. Multiple closed population models were evaluated, with Chao M(h) ranking best in model performance and yielding a population estimate of 668 sharks with 95% confidence intervals ranging from 289-1720. Low shark abundance in the shallow lagoon habitats suggests removal of a small number of sharks from the immediate vicinity of lagoonal islets may reduce short-term predation on endangered monk seal (Monachus schauinslandi) pups, but considerable fishing effort would be required to catch even a small number of sharks. Additional data on long-term movements and habitat use of sharks at FFS are required to better assess the likely ecological impacts of shark culling.

  15. Proximity to encroaching coconut palm limits native forest water use and persistence on a Pacific atoll

    Science.gov (United States)

    Krauss, Ken W.; Duberstein, Jamie A.; Cormier, Nicole; Young, Hillary S.; Hathaway, Stacie A.

    2015-01-01

    Competition for fresh water between native and introduced plants is one important challenge facing native forests as rainfall variability increases. Competition can be especially acute for vegetation on Pacific atolls, which depend upon consistent rainfall to replenish shallow groundwater stores. Patterns of sap flow, water use, and diameter growth of Pisonia grandis trees were investigated on Sand Islet, Palmyra Atoll, Line Islands, during a period of low rainfall. Sap flow in the outer sapwood was reduced by 53% for P. grandis trees growing within coconut palm (Cocos nucifera) stands (n = 9) versus away from coconut palm (n = 9). This suggested that water uptake was being limited by coconut palm. Radial patterns of sap flow into the sapwood of P. grandis also differed between stands with and without coconut palm, such that individual tree water use for P. grandis ranged from 14 to 67 L day−1, averaging 47·8 L day−1 without coconut palm and 23·6 L day−1 with coconut palm. Diameter growth of P. grandis was measured from nine islets. In contrast to sap flow, competition with coconut palm increased diameter growth by 89%, equating to an individual tree basal area increment of 5·4 versus 10·3 mm2 day−1. Greater diameter growth countered by lower rates of water use by P. grandis trees growing in competition with coconut palm suggests that stem swell may be associated with water storage when positioned in the understory of coconut palm, and may facilitate survival when water becomes limiting until too much shading overwhelms P. grandis. 

  16. Preliminary hard and soft bottom seafloor substrate map (5m grid) derived from an unsupervised classification of gridded backscatter and bathymetry derivatives at Rose Atoll Lagoon, Territory of American Samoa, USA.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Preliminary hard and soft seafloor substrate map derived from an unsupervised classification of multibeam backscatter and bathymetry derivatives at Rose Atoll...

  17. National Coral Reef Monitoring Program: Stratified Random Surveys (StRS) of Coral Demography (Adult and Juvenile Corals) across Rose Atoll from 2016-05-01 to 2016-05-04 (NCEI Accession 0159167)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The data described here result from benthic coral demographic surveys for two life stages (juveniles, adults) across Rose Atoll in 2016. Juvenile colony surveys...

  18. ASM-Triggered Too Observations of Kilohertz Oscillations in Three Atoll Sources

    Science.gov (United States)

    Kaaret, P.; Swank, Jean (Technical Monitor)

    2000-01-01

    Three Rossi Timing Explorer (RXTE) observations were carried out for this proposal based on target of opportunity triggers derived from the All-Sky Monitor (ASM) on RXTE. We obtained short observations of 4U1636-536 (15ks) and 4U1735-44 (23ks) and a longer observation of 4U0614+091 (117ks). Our analysis of our observations of the atoll neutron star x-ray binary 4U1735-44 lead to the discovery of a second high frequency quasiperiodic oscillation (QPO) in this source. These results were published in the Astrophysical Journal Letters. The data obtained on the source 4U0614+091 were used in a comprehensive study of this source, which will be published in the Astrophysical Journal. The data from this proposal were particularly critical for that study as they lead to the detection of the highest QPO frequency every found in the x-ray emission from an x-ray binary which will be important in placing limits on the equation of state of nuclear matter.

  19. Projected atoll shoreline and run-up changes in response to sea-level rise and varying large wave conditions at Wake and Midway Atolls, Northwestern Hawaiian Islands

    Science.gov (United States)

    Shope, James B.; Storlazzi, Curt; Hoeke, Ron

    2017-01-01

    Atoll islands are dynamic features that respond to seasonal alterations in wave conditions and sea level. It is unclear how shoreline wave run-up and erosion patterns along these low elevation islands will respond to projected sea-level rise (SLR) and changes in wave climate over the next century, hindering communities' preparation for the future. To elucidate how these processes may respond to climate change, extreme boreal winter and summer wave conditions under future sea-level rise (SLR) and wave climate scenarios were simulated at two atolls, Wake and Midway, using a shallow-water hydrodynamic model. Nearshore wave conditions were used to compute the potential longshore sediment flux along island shorelines via the CERC empirical formula and wave-driven erosion was calculated as the divergence of the longshore drift; run-up and the locations where the run-up exceed the berm elevation were also determined. SLR is projected to predominantly drive future island morphological change and flooding. Seaward shorelines (i.e., ocean fronted shorelines directly facing incident wave energy) were projected to experience greater erosion and flooding with SLR and in hypothetical scenarios where changes to deep water wave directions were altered, as informed by previous climate change forced Pacific wave modeling efforts. These changes caused nearshore waves to become more shore-normal, increasing wave attack along previously protected shorelines. With SLR, leeward shorelines (i.e., an ocean facing shoreline but sheltered from incident wave energy) became more accretive on windward islands and marginally more erosive along leeward islands. These shorelines became more accretionary and subject to more flooding with nearshore waves becoming more shore-normal. Lagoon shorelines demonstrated the greatest SLR-driven increase in erosion and run-up. They exhibited the greatest relative change with increasing wave heights where both erosion and run-up magnitudes increased. Wider

  20. Projected atoll shoreline and run-up changes in response to sea-level rise and varying large wave conditions at Wake and Midway Atolls, Northwestern Hawaiian Islands

    Science.gov (United States)

    Shope, James B.; Storlazzi, Curt D.; Hoeke, Ron K.

    2017-10-01

    Atoll islands are dynamic features that respond to seasonal alterations in wave conditions and sea level. It is unclear how shoreline wave run-up and erosion patterns along these low elevation islands will respond to projected sea-level rise (SLR) and changes in wave climate over the next century, hindering communities' preparation for the future. To elucidate how these processes may respond to climate change, extreme boreal winter and summer wave conditions under future sea-level rise (SLR) and wave climate scenarios were simulated at two atolls, Wake and Midway, using a shallow-water hydrodynamic model. Nearshore wave conditions were used to compute the potential longshore sediment flux along island shorelines via the CERC empirical formula and wave-driven erosion was calculated as the divergence of the longshore drift; run-up and the locations where the run-up exceed the berm elevation were also determined. SLR is projected to predominantly drive future island morphological change and flooding. Seaward shorelines (i.e., ocean fronted shorelines directly facing incident wave energy) were projected to experience greater erosion and flooding with SLR and in hypothetical scenarios where changes to deep water wave directions were altered, as informed by previous climate change forced Pacific wave modeling efforts. These changes caused nearshore waves to become more shore-normal, increasing wave attack along previously protected shorelines. With SLR, leeward shorelines (i.e., an ocean facing shoreline but sheltered from incident wave energy) became more accretive on windward islands and marginally more erosive along leeward islands. These shorelines became more accretionary and subject to more flooding with nearshore waves becoming more shore-normal. Lagoon shorelines demonstrated the greatest SLR-driven increase in erosion and run-up. They exhibited the greatest relative change with increasing wave heights where both erosion and run-up magnitudes increased. Wider

  1. Drivers of abundance and spatial distribution of reef-associated sharks in an isolated atoll reef system.

    Directory of Open Access Journals (Sweden)

    David M Tickler

    Full Text Available We investigated drivers of reef shark demography across a large and isolated marine protected area, the British Indian Ocean Territory Marine Reserve, using stereo baited remote underwater video systems. We modelled shark abundance against biotic and abiotic variables at 35 sites across the reserve and found that the biomass of low trophic order fish (specifically planktivores had the greatest effect on shark abundance, although models also included habitat variables (depth, coral cover and site type. There was significant variation in the composition of the shark assemblage at different atolls within the reserve. In particular, the deepest habitat sampled (a seamount at 70-80m visited for the first time in this study recorded large numbers of scalloped hammerhead sharks (Sphyrna lewini not observed elsewhere. Size structure of the most abundant and common species, grey reef sharks (Carcharhinus amblyrhynchos, varied with location. Individuals at an isolated bank were 30% smaller than those at the main atolls, with size structure significantly biased towards the size range for young of year (YOY. The 18 individuals judged to be YOY represented the offspring of between four and six females, so, whilst inconclusive, these data suggest the possible use of a common pupping site by grey reef sharks. The importance of low trophic order fish biomass (i.e. potential prey in predicting spatial variation in shark abundance is consistent with other studies both in marine and terrestrial systems which suggest that prey availability may be a more important predictor of predator distribution than habitat suitability. This result supports the need for ecosystem level rather than species-specific conservation measures to support shark recovery. The observed spatial partitioning amongst sites for species and life-stages also implies the need to include a diversity of habitats and reef types within a protected area for adequate protection of reef-associated shark

  2. Challenges and Opportunities for Sustainable Tourism Development in Ulithi Atoll

    Directory of Open Access Journals (Sweden)

    Anna Ongaro

    2016-07-01

    Full Text Available This article aims to analyze the tourism potential of Ulithi Atoll, in the Federated States of Micronesia. It identifies possibilities for sustainable tourism development, while taking into account the major issues that threaten the environment, the cultural integrity and the future of the local community. Through a review of existing research and an assessment of the web presence, the study develops a diagnosis of the current situation of the tourism sector in the destination. The tourism potential of Ulithi mainly relies on its beautiful physical environment and authentic cultural heritage, but it is still largely untapped due to limited development. Tourism represents a strategic tool for the economic growth and empowerment of Ulithi community. Presently, however, the atoll’s biggest problem is the recovery from the recent disastrous Typhoon Maysak. Other pressing challenges are climate change and the erosion of traditional knowledge. The study identifies ecotourism and voluntourism as key niche market opportunities for the destination. Encouraging greater participation among the stakeholders and a concrete commitment to sustainability within the strategic plans are some of the recommendations that aim to build the tourism industry in a way that supports the local culture, the natural resources and the way of life.

  3. Zoogeography of the shorefish fauna of Clipperton Atoll

    Science.gov (United States)

    Robertson, D. R.; Allen, G. R.

    1996-06-01

    One hundred and fifteen species of fishes (14 oceanic, plus 101 shore and nearshore species) are known from Clipperton Island, a small, remote coral atoll in the tropical eastern Pacific (TEP). This fish fauna includes only ˜ 14% of the region's shallow-water species, and also is depauperate relative to the fish faunas of other isolated tropical islands. The island's isolation, small size, reduced habitat diversity, and oceanic environment contribute to this paucity of species. Fifty-two species at Clipperton can be identified as TEP; these include 37 widespread species, six species shared only with the Revillagigedo Islands [the nearest (950 km) offshore shoals], and eight endemic to Clipperton. Endemics species apparently have a mix of west and east Pacific origins. Sixty-three species are transpacific; they include three new records (of Naso surgeonfishes) that maybe vagrants recruited > 4,000 km from Oceania. Clipperton is situated at the juncture between the TEP and Oceania. Its fish fauna contains about equal numbers of TEP and transpacific species. This faunal structure reflects the relative influence of surface currents from Oceania and the TEP. Although most of Clipperton's transpacific shorefishes are widespread in eastern Oceania, the Clipperton fauna has specific affinities to the fauna of the Line Islands, which are located within the main eastbound current from Oceania. Clipperton may therefore be a major stepping stone for dispersal between Oceania and the remainder of the TEP. About 50% of the non-oceanic, tropical transpacific fishes occur there, and at least 75 % of those species apparently have resident populations at the island.

  4. Certified reference materials for radionuclides in Bikini Atoll sediment (IAEA-410) and Pacific Ocean sediment (IAEA-412)

    DEFF Research Database (Denmark)

    Pham, M. K.; van Beek, P.; Carvalho, F. P.

    2016-01-01

    The preparation and characterization of certified reference materials (CRMs) for radionuclide content in sediments collected offshore of Bikini Atoll (IAEA-410) and in the open northwest Pacific Ocean (IAEA-412) are described and the results of the certification process are presented. The certified...... radionuclides include: 40K, 210Pb (210Po), 226Ra, 228Ra, 228Th, 232Th, 234U, 238U, 239Pu, 239+240Pu and 241Am for IAEA-410 and 40K, 137Cs, 210Pb (210Po), 226Ra, 228Ra, 228Th, 232Th, 235U, 238U, 239Pu, 240Pu and 239+240Pu for IAEA-412. The CRMs can be used for quality assurance and quality control purposes...

  5. Magnetic susceptibility evolution and sedimentary environments on carbonate platform sediments and atolls, comparison of the Frasnian from Belgium and Alberta, Canada

    Science.gov (United States)

    da Silva, Anne-Christine; Potma, Ken; Weissenberger, John A. W.; Whalen, Michael T.; Humblet, Marc; Mabille, Cédric; Boulvain, Frédéric

    2009-02-01

    Magnetic susceptibility (MS) measurements on carbonate rocks are considered as a proxy for impurities delivered to the carbonate environments. In the absence of strong climatic or tectonic variations, bulk MS values have been linked to sea level variations, because sea-level fall increases clastic supply and therefore increases in magnetic mineral deposition. In this paper we explore the relationship between the average magnitude of bulk MS, with shallowing-up sequences and facies evolution in different Devonian carbonate complexes. Similarities and differences between these parameters have been scrutinized in carbonate attached platform and detached platforms (mounds and/or atolls) from Belgium and Canada. In the carbonate attached platforms from Belgium and Canada, the MS patterns are directly related to depositional environment. Mean MS values increase from the most distal towards the most proximal facies and towards the top of the majority of fourth-order shallowing-up sequences. These trends are in agreement with theoretical background (MS increases with regression). In the Belgian detached platform, the average MS pattern generally shows an opposite behaviour to that observed in the attached carbonate platforms. Average MS decreases towards the most proximal facies and towards the top of a majority of the fourth-order shallowing-up sequences. This behaviour can be explained by the influence of sedimentary rate and water agitation during deposition. A high sedimentary rate will dilute the magnetic minerals in the atoll facies and the high water agitation during deposition may be expected to have prevented the deposition of the magnetic grains. So, the combination of these two effects will result in the observed low values in the atoll crown and lagoonal facies. In the Canadian detached platform, MS is mainly negative. This means that the limestones are very pure. The technique does not appear to be appropriate in these rocks. The variations of average MS

  6. Mineralogy, geochemistry and microfacies of late Quaternary periplatform sediments: Carbonate export cycles and secondary processes - Sanganeb Atoll and Abington Reef, Sudan, Central Red Sea

    OpenAIRE

    Emmermann, Peter

    2000-01-01

    A set of sediment cores was obtained in the periplatform realm close to Sanganeb Atoll and Abington Reef, about 20 miles offshore the Sudanese coast in the central Red Sea. Microfacies, mineralogy and geochemistry of periplatform sediments were analysed to quantify glacial-interglacial variations in carbonate production and sediment export of the reefs in response to late Quaternary sealevel fluctuations. The present study showed that the periplatform sediments from the Sudanese shelf to grea...

  7. Efforts to eradicate yellow crazy ants on Johnston Atoll: Results from Crazy Ant Strike Team IX, December 2014-June 2015

    Science.gov (United States)

    Banko, Paul C.; Peck, Robert W.; Donmoyer, Kevin; Kropidlowski, Stephan; Pollock, Amanda

    2015-01-01

    The ecologically destructive yellow crazy ant (YCA; Anoplolepis gracilipes) was first detected on Johnston Atoll in January 2010. Within eight months, the U.S. Fish and Wildlife Service had mobilized its first crazy ant strike team (CAST), a group of biologists dedicated to testing and identifying insecticidal baits to be used to eradicate the ant on the atoll. During December 2014‒May 2015 CAST IX focused on testing hydrogel crystals saturated with sucrose solution (25%) carrying the insecticides thiamethoxam and dinotefuran against YCA. A series of experiments, including artificial nest box trials, and field-based palatability trials and eradication tests on small (500 m2 or 0.05 ha) and large plots (2500 m2 or 0.25 ha), were conducted to test concentrations of thiamethoxam ranging from 0.0005% to 0.01%, and dinotefuran at 0.05%. Additionally, the cat food-based matrix containing dinotefuran (0.05%), the standard bait used to suppress YCA on Johnston since 2011, and textured vegetable protein (TVP) carrying dinotefuran at 0.1% and 0.05% were included in large plot tests. Nest box trials were inconclusive due to a consistent loss of queen and worker ants in control boxes, so they were discontinued. Palatability trials suggested higher dosages of thiamethoxam (0.005 and 0.01%) were less attractive than lower dosages (0.0005 and 0.001%) and controls (sucrose only), but small and large plot experiments failed to identify a thiamethoxam concentration that was consistently effective at killing YCA. In contrast, hydrogel containing dinotefuran was consistently effective, killing >95% of YCA on small and large plots. As expected, the cat food bait effectively reduced YCA abundances, but was slightly less effective than hydrogel containing dinotefuran over time. Three successive, approximately weekly treatments of large plots with hydrogel bait, or other baits followed by hydrogel bait, suggest an increasing overall effectiveness, with no aversion of YCA to the bait

  8. Análisis de las estrategias de gestión del espectro radioeléctrico en un sistema LTE con la herramienta Atoll

    OpenAIRE

    López Diaz, Eduardo José

    2012-01-01

    Estudiar el impacto de usar una estrategia ICIC y los posibles esquemas de reuso frecuencial en un sistema LTE. English: the Mobile Communications Research Group as part of the Signal Theory and Communications Department of the Polytechnic University of Catalonia, in order to keep up with the latest technological trends in the mobile networks field, saw the need to study and analyze the new emerging mobile standards such as LTE (Long Term Evolution), and through Atoll, a mobile network rad...

  9. Sedimentary facies and Holocene depositional processes of Laura Island, Majuro Atoll

    Science.gov (United States)

    Yasukochi, Toru; Kayanne, Hajime; Yamaguchi, Toru; Yamano, Hiroya

    2014-10-01

    The depositional processes that formed Laura Island, Majuro Atoll, Marshall Islands, were reconstructed based on a facies analysis of island sediments and spine ratios, and radiocarbon ages of foraminifera. Sedimentary facies were analyzed from trenches and drill cores excavated on the island and its adjacent reef flat. Depositional ages were obtained using benthic foraminifera (Calcarina) whose spines had not been abraded. The facies were classified into two types: gravelly and sandy. The initial sediments of these sites consisted of gravelly facies in the lower horizon and sandy facies in the upper horizon. Their ages were approximately 2000 cal BP and coincident with the onset of a 1.1-m decline in regional relative sea level, which enabled deposition of the gravelly facies. Half of the sand fraction of the sediment was composed of larger benthic foraminifera. The spine ratio showed that their supply source on the reef flat was located oceanside of the island. The supply source appears to have been caused by the relative sea-level fall. This indicates that the studied island was formed by a relative reduction in wave energy and enhanced foraminiferal supply, both of which were triggered by the late Holocene relative sea-level fall.

  10. Derivation of plant-soil relationships for dose assessment on Bikini Atoll

    International Nuclear Information System (INIS)

    Colsher, C.S.

    1976-11-01

    A radiological survey of the terrestrial environment of Bikini and Eneu Islands (Bikini Atoll) was conducted in June 1975 to evaluate the potential radiation dose to the returning Bikini population. This report presents measurements of the radionuclide concentration in soil profiles and in dominant species of edible and nonedible indicator plants and describes the use of these data to derive relationships to predict the plant uptake of radionuclides from soil. Soil-plant concentration factors together with leaf-leaf and fruit-leaf concentration ratios for indicator and edible plant species from the same area are calculated to quantitatively assess and compare the uptake of 90 Sr, 137 Cs, and 239 ' 240 Pu. In general, the concentration factors for 137 Cs in terrestrial vegetation are greater than those for 90 Sr and the concentration factors for both these nuclides exceed those for 239 ' 240 Pu by ten to one hundred-fold. Uptake of 90 Sr and 239 ' 240 Pu by fruit is less than that by mature leaves; however, the opposite is true for 137 Cs. The relative contribution of the individual plant species to the internal dose to man varies with the nuclide. The use of concentration factors and concentration ratios to predict nuclide concentrations in fruit from those in soil or leaves is prescribed

  11. Whale shark economics: a valuation of wildlife tourism in South Ari Atoll, Maldives

    KAUST Repository

    Cagua, Edgar F.

    2014-08-12

    Whale sharks attract large numbers of tourists, divers and snorkelers each year to South Ari Atoll in the Republic of Maldives. Yet without information regarding the use and economic extent of the attraction, it is difficult to prioritize conservation or implement effective management plans. We used empirical recreational data and generalized mixed statistical models to conduct the first economic valuation (with direct spend as the primary proxy) of whale shark tourism in Maldives. We estimated that direct expenditures for whale shark focused tourism in the South Ari Marine Protected Area for 2012 and 2013 accounted for US$7.6 and $9.4 million respectively. These expenditures are based on an estimate of 72,000-78,000 tourists who are involved in whale shark excursions annually. That substantial amount of income to resort owners and operators, and tourism businesses in a relatively small area highlights the need to implement regulations and management that safeguard the sustainability of the industry through ensuring guest satisfaction and whale shark conservation. © 2014 Cagua et al.

  12. Ages of subsurface stratigraphic intervals in the Quaternary of Enewetak Atoll, Marshall Islands

    Science.gov (United States)

    Szabo, B. J.; Tracey, J.I.; Goter, E.R.

    1985-01-01

    Drill cores of Enewetak Atoll, Marshall Islands, reveal six stratigraphic intervals, numbered in downward sequence, which represent vertical coral growth during Quaternary interglaciations. Radiocarbon dates indicate that the Holocene sea transgressed the emergent reef platform by about 8000 yr B.P. The reef grew rapidly upward (about 5 to 10 mm/yr) until about 6500 yr B.P. Afterward vertical growth slowed to about 0.5 mm/yr, then lateral development became dominant during the last several thousand years. The second interval is dated at 131,000 ?? 3000 yr B.P. by uranium series. This unit correlates with oxygen-isotope substage 5e and with terrace VIIa of Huon Peninsula, New Guinea, and of Main Reef-2 terrace at Atauro Island. The third interval is not dated because corals were recrystallized and it is tentatively correlated with either oxygen-isotope stages 7 or 9. The age of the fourth interval is estimated at 454,000 ?? 100,000 yr B.P. from measured 234U 238U activity ratios. This unit is correlated with either oxygen-isotope stage 9, 11, or 13. ?? 1985.

  13. Past and present levels of some radionuclides in fish from Bikini and Enewetak Atolls.

    Science.gov (United States)

    Noshkin, V E; Robison, W L; Wong, K M; Brunk, J L; Eagle, R J; Jones, H E

    1997-07-01

    Bikini and Enewetak were the sites in the Northern Marshall Islands that were used by the United States as testing grounds for nuclear devices between 1946 and 1958. The testing produced close-in fallout debris that was contaminated with different radionuclides and which entered the aquatic environment. The contaminated lagoon sediments became a reservoir and source term of manmade radionuclides for the resident marine organisms. This report contains a summary of all the available data on the concentrations of 137Cs, 60Co and 207Bi in flesh samples of reef and pelagic fish collected from Bikini and Enewetak Atolls between 1964 and 1995. The selection of these three radionuclides for discussion is based on the fact that these are the only radionuclides that have been routinely detected by gamma spectrometry in flesh samples from all fish for the last 20 y. Flesh from fish is an important source of food in the Marshallese diet. These radionuclides along with the transuranic radionuclides and 90Sr contribute most of the small radiological dose from ingesting marine foods. Some basic relationships among concentrations in different tissues and organs are discussed. The reef fish can be used as indicator species because their body burden is derived from feeding, over a lifetime, within a relatively small contaminated area of the lagoon. Therefore, the emphasis of this report is to use this extensive and unique concentration data base to describe the effective half lives and cycling for the radionuclides in the marine environments during the 31-y period between 1964 and 1995. The results from an analysis of the radionuclide concentrations in the flesh samples indicate the removal rates for the 3 radionuclides are significantly different. 137Cs is removed from the lagoons with an effective half life of 9-12 y. Little 60Co is mobilized to the water column so that it is depleted in both environments, primarily through radioactive decay. The properties of 207Bi are different

  14. Local extinction of the Asian tiger mosquito (Aedes albopictus) following rat eradication on Palmyra Atol

    Science.gov (United States)

    Lafferty, Kevin D.; McLaughlin, John P.; Gruner, Daniel S.; Bogar, Taylor A.; Bui, An; Childress, Jasmine N.; Espinoza, Magaly; Forbes, Elizabeth S.; Johnston, Cora A.; Klope, Maggie; Kuile, Ana Miller-ter; Lee, Michelle; Plummer, Katherine A.; Weber, David A.; Young, Ronald T.; Young, Hillary S.

    2018-01-01

    The Asian tiger mosquito, Aedes albopictus, appears to have been extirpated from Palmyra Atoll following rat eradication. Anecdotal biting reports, collection records, and regular captures in black-light traps showed the species was present before rat eradication. Since then, there have been no biting reports and no captures over 2 years of extensive trapping (black-light and scent traps). By contrast, the southern house mosquito, Culex quinquefasciatus, was abundant before and after rat eradication. We hypothesize that mammals were a substantial and preferred blood meal for Aedes, whereas Culex feeds mostly on seabirds. Therefore, after rat eradication, humans and seabirds alone could not support positive population growth or maintenance of Aedes. This seems to be the first documented accidental secondary extinction of a mosquito. Furthermore, it suggests that preferred host abundance can limit mosquito populations, opening new directions for controlling important disease vectors that depend on introduced species like rats.

  15. Providing an authorization for an ex gratia payment to the people of Bikini Atoll, in the Marshall Islands of the Trust Territory of the Pacific Islands. Senate, Ninety-Fourth Congress, First Session, June 2, 1975

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    Proposed legislation for payment of dollars 3 million ex gratia to the people of Bikini Atoll due to their relocation resulting from nuclear-weapons testing and successive contamination of their homeland is presented. The Committee on Interior and Insular Affairs recommends passage

  16. An updated dose assessment for resettlement options at Bikini Atoll--a U.S. nuclear test site.

    Science.gov (United States)

    Robison, W L; Bogen, K T; Conrado, C L

    1997-07-01

    On 1 March 1954, a nuclear weapon test, code-named BRAVO, conducted at Bikini Atoll in the northern Marshall Islands contaminated the major residence island. There has been a continuing effort since 1977 to refine dose assessments for resettlement options at Bikini Atoll. Here we provide a radiological dose assessment for the main residence island, Bikini, using extensive radionuclide concentration data derived from analysis of food crops, ground water, cistern water, fish and other marine species, animals, air, and soil collected at Bikini Island as part of our continuing research and monitoring program that began in 1978. The unique composition of coral soil greatly alters the relative contribution of 137Cs and 90Sr to the total estimated dose relative to expectations based on North American and European soils. Without counter measures, 137Cs produces 96% of the estimated dose for returning residents, mostly through uptake from the soil to terrestrial food crops but also from external gamma exposure. The doses are calculated assuming a resettlement date of 1999. The estimated maximum annual effective dose for current island conditions is 4.0 mSv when imported foods, which are now an established part of the diet, are available. The 30-, 50-, and 70-y integral effective doses are 91 mSv, 130 mSv, and 150 mSv, respectively. A detailed uncertainty analysis for these dose estimates is presented in a companion paper in this issue. We have evaluated various countermeasures to reduce 137Cs in food crops. Treatment with potassium reduces the uptake of 137Cs into food crops, and therefore the ingestion dose, to about 5% of pretreatment levels and has essentially no negative environmental consequences. We have calculated the dose for the rehabilitation scenario where the top 40 cm of soil is removed in the housing and village area, and the rest of the island is treated with potassium fertilizer; the maximum annual effective dose is 0.41 mSv and the 30-, 50-, and 70-y

  17. Vertical and horizontal genetic connectivity in Chromis verater, an endemic damselfish found on shallow and mesophotic reefs in the Hawaiian Archipelago and adjacent Johnston Atoll.

    Science.gov (United States)

    Tenggardjaja, Kimberly A; Bowen, Brian W; Bernardi, Giacomo

    2014-01-01

    Understanding vertical and horizontal connectivity is a major priority in research on mesophotic coral ecosystems (30-150 m). However, horizontal connectivity has been the focus of few studies, and data on vertical connectivity are limited to sessile benthic mesophotic organisms. Here we present patterns of vertical and horizontal connectivity in the Hawaiian Islands-Johnston Atoll endemic threespot damselfish, Chromis verater, based on 319 shallow specimens and 153 deep specimens. The mtDNA markers cytochrome b and control region were sequenced to analyze genetic structure: 1) between shallow (shallow and mesophotic populations. There was no significant genetic differentiation by depth, indicating high levels of vertical connectivity between shallow and deep aggregates of C. verater. Consequently, shallow and deep samples were combined by location for analyses of horizontal connectivity. We detected low but significant population structure across the Hawaiian Archipelago (overall cytochrome b: ΦST = 0.009, P = 0.020; control region: ΦST = 0.012, P = 0.009) and a larger break between the archipelago and Johnston Atoll (cytochrome b: ΦST = 0.068, P deep reefs may constitute a population reservoir for species depleted in shallow reef habitats. These findings represent the first connectivity study on a mobile organism that spans shallow and mesophotic depths and provide a reference point for future connectivity studies on mesophotic fishes.

  18. Report on the intercomparison run: radionuclides in seawater and plankton collected outside Mururoa Atoll

    International Nuclear Information System (INIS)

    Ballestra, S.; Noshkin, V.

    1991-07-01

    This report contains a brief outline of the sampling program and a summary of all available radiological data provided by the three participants. The Direction des Centres d'Experimentations Nucleaires Laboratory (DIRCEN-CEA), Montlhery, France; The Lawrence Livermore National Laboratory (LLNL), Livermore, CA, USA; and the IAEA International Laboratory of Marine Radioactivity, (IAEA-ILMR), Principality of Monaco. The IAEA-ILMR results are complied in a separate report by Ballestra et al. (1991) that has details of the program and copies of the protocol and the ''Proces-verbal de constat'' produced by the legal representative at the end of the sampling program. A sampling program was designed to collect 3 large volume seawater and 2 plankton samples from locations near the territorial limit outside Mururoa Atoll. The different samples were to be used for a radiological intercomparison exercise. A legal representative from Papeete, Tahiti (French Polynesia) was given the task to verify the authenticity of the samples and to ensure that the protocol was followed by the participants. 4 refs, 1 fig., 3 tabs

  19. Sediment studies at Bikini Atoll part 2. inventories of transuranium elements in surface sediments

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Robison, W.L.

    1997-10-01

    This is the second of three reports on Bikini sediment studies, which discusses the concentrations and inventories of {sup 241}Am and {sup 239+240}Pu in sediments from the lagoon. Surface sediment samples were collected from 87 locations over the entire lagoon at Bikini Atoll during 1979. The collections were made to map the distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred in the composition of the sediment as a result of the testing program. Present inventories for {sup 241}Am and {sup 239+240}Pu in the surface 2 cm of sediment are estimated to be 14 and 17 TBq, respectively. These values are estimated to represent only 14% of the total inventory in the sediment column. Sediment inventories of {sup 239+240}Pu and {sup 241}Am are changing only slowly with time through chemical- physical processes that continuously mobilize small amounts of the transuranics to the water column. The lowest concentrations and inventories are associated with deposits logoonward of the eastern reef.

  20. In situ determination of 241Am on Enewetak Atoll. Date of survey: July 1977-December 1979

    International Nuclear Information System (INIS)

    Tipton, W.J.; Fritzsche, A.E.; Jaffe, R.J.; Villaire, A.E.

    1981-11-01

    An in situ gamma ray spectrometer system was operated at Enewetak Atoll from July 1977 to December 1979 in support of the Enewetak Cleanup Project. The system employed a high purity germanium planar detector suspended at a height of 7.4 m above ground. Conversion factors were established to relate measured photopeak count rate data to source concentration in the soil. Data obtained for 241 Am, together with plutonium-to-americium ratios obtained from soil sample analyses, were used to establish area-averaged surface (0 to 3 cm) transuranic concentration values. In areas which exceeded cleanup criteria, measurements were made in an iterative fashion to guide soil removal until levels were reduced below the cleanup criteria. Final measurements made after soil removal had been completed were used to document remaining surface transuranic concentration values and to establish external exposure rate levels due to 137 Cs and 60 Co

  1. Human impacts on large benthic foraminifers near a densely populated area of Majuro Atoll, Marshall Islands

    International Nuclear Information System (INIS)

    Osawa, Yoko; Fujita, Kazuhiko; Umezawa, Yu; Kayanne, Hajime; Ide, Yoichi; Nagaoka, Tatsutoshi; Miyajima, Toshihiro; Yamano, Hiroya

    2010-01-01

    Human impacts on sand-producing, large benthic foraminifers were investigated on ocean reef flats at the northeast Majuro Atoll, Marshall Islands, along a human population gradient. The densities of dominant foraminifers Calcarina and Amphistegina declined with distance from densely populated islands. Macrophyte composition on ocean reef flats differed between locations near sparsely or densely populated islands. Nutrient concentrations in reef-flat seawater and groundwater were high near or on densely populated islands. δ 15 N values in macroalgal tissues indicated that macroalgae in nearshore lagoons assimilate wastewater-derived nitrogen, whereas those on nearshore ocean reef flats assimilate nitrogen from other sources. These results suggest that increases in the human population result in high nutrient loading in groundwater and possibly into nearshore waters. High nutrient inputs into ambient seawater may have both direct and indirect negative effects on sand-producing foraminifers through habitat changes and/or the collapse of algal symbiosis.

  2. The Concentration and Distribution of Depleted Uranium (DU) and Beryllium (Be) in Soil and Air on Illeginni Island at Kwajalein Atoll

    International Nuclear Information System (INIS)

    Robison, W L; Hamilton, T F; Martinelli, R E; Gouveia, F J; Lindman, T R; Yakuma, S C

    2006-01-01

    Re-entry vehicles on missiles launched at Vandenberg Air Force base in California re-enter at the Western Test Range, the Regan Test Site (RTS) at Kwajalein Atoll. An environmental Assessment (EA) was written at the beginning of the program to assess potential impact of Depleted Uranium (DU) and Beryllium (Be), the major RV materials of interest from a health and environmental perspective. The chemical and structural form of DU and Be in RVs is such that they are insoluble in soil water and sea water. Consequently, residual concentrations of DU and Be observed in soil on the island are not expected to be toxic to plant life because there is essentially no soil to plant uptake. Similarly, due to their insolubility in sea water there is no uptake of either element by marine biota including fish, mollusks, shellfish and sea mammals. No increase in either element has been observed in sea life around Illeginni Island where deposition of DU and Be has occurred. The critical terrestrial exposure pathway for U and Be is inhalation. Concentration of both elements in air over the test period (1989 to 2006) is lower by a factor of 10,000 than the most restrictive U.S. guideline for the general public. Uranium concentrations in air are also lower by factors of 10 to 100 than concentrations of U in air in the U.S. measured by the EPA (Keith et al., 1999). U and Be concentrations in air downwind of deposition areas on Illeginni Island are essentially indistinguishable from natural background concentrations of U in air at the atolls. Thus, there are no health related issues associated with people using the island

  3. Dynamics of radionuclide exchange in the calcareous algae Halimeda at Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Spies, R.B.; Marsh, K.V.; Kercher, J.R.

    1981-01-01

    Measurements of /sup 239+240/Pu in the detrital inclusions and in acid-soluble and acid-insoluble fractions of Halimeda macrophysa showed a 10-fold higher concentration in the acid-insoluble coenocytic filaments than in the acid-soluble fraction. In a depuration experiment with Halimeda incrassata at Enewetak Atoll the loss rate of six radionuclides was measured. Data for /sup 60/Co, /sup 137/Cs, and /sup 102m/Rh were fit to loss curves by using one term for exponential loss; data for /sup 155/Eu, /sup 239+240/Pu, and /sup 241/Am required two terms. For each radionuclide, compartment size and transfer functions were determined for the appropriate one- and two-compartment models. Of 26 possible two-compartment models, only seven gave solutions with our data. Nearly identical loss rates were obtained for /sup 155/Eu, /sup 239+240/Pu, and /sup 241/Am in the fast-exchanging compartments for all seven models. The uptake rates for these nuclides were also similar when uptake rates were normalized to local sediment concentrations. The fast-exchanging compartment probably corresponds to the mucilage surface layer of the coenocytic filaments. The identity of the slow-exchanging compartment is less certain but it may correspond to the skeletal surface.

  4. Dynamics of radionuclide exchange in the calcareous algae Halimeda at Enewetak Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Spies, R.B. (Lawrence Livermore Lab., CA); Marsh, K.V.; Kercher, J.R.

    1981-01-01

    Measurements of /sup 239 +240/Pu in the detrital inclusions and in acid-soluble and acid-insoluble fractions of Halimeda macrophysa showed a 10-fold higher concentration in the acid-insoluble coenocytic filaments than in the acid-soluble fraction. In a depuration experiment with Halimeda incrassata at Enewetak Atoll the loss rate of six radionuclides was measured. Data for /sup 60/Co, /sup 137/Cs, and /sup 102//sup m/Rh were fit to loss curves by using one term for exponential loss; data for /sup 155/Eu, /sup 239 +240/Pu, and /sup 241/Am required two terms. For each radionuclide, compartment size and transfer functions were determined for the apropriate one- and two-compartment models. Of 26 possible two-compartment models, only seven gave solutions with our data. Nearly identical loss rates were obtained for /sup 155/Eu, /sup 239 +240/Pu, and /sup 241/Am in the fast-exchanging compartments for all seven models. The uptake rates for these nuclides were also similar when uptake rates were normalized to local sediment concentrations. The fast-exchanging compartment probably corresponds to the mucilage surface layer of the coenocytic filaments. The identity of the slow-exchanging compartment is less certain but it may correspond to the skeletal surface.

  5. Genetic diversity of Wolbachia endosymbionts in Culex quinquefasciatus from Hawai`i, Midway Atoll, and Samoa

    Science.gov (United States)

    Atkinson, Carter T.; Watcher-Weatherwax, William; Lapointe, Dennis

    2016-01-01

    Incompatible insect techniques are potential methods for controlling Culex quinquefasciatus and avian disease transmission in Hawai‘i without the use of pesticides or genetically modified organisms. The approach is based on naturally occurring sperm-egg incompatibilities within the Culex pipiens complex that are controlled by different strains of the bacterial endosymbiont Wolbachia pipientis (wPip). Incompatibilities can be unidirectional (crosses between males infected with strain A and females infected with strain B are fertile, while reciprocal crosses are not) or bidirectional (reciprocal crosses between sexes with different wPip strains are infertile). The technique depends on release of sufficient numbers of male mosquitoes infected with an incompatible wPip strain to suppress mosquito populations and reduce transmission of introduced avian malaria (Plasmodium relictum) and Avipoxvirus in native forest bird habitats. Both diseases are difficult to manage using more traditional methods based on removal and treatment of larval habitats and coordination of multiple approaches may be needed to control this vector. We characterized the diversity of Wolbachia strains in C. quinquefasciatus from Hawai‘i, Kaua‘i, Midway Atoll, and American Samoa with a variety of genetic markers to identify compatibility groups and their distribution within and between islands. We confirmed the presence of wPip with multilocus sequence typing, tested for local genetic variability using 16 WO prophage genes, and identified similarities to strains from other parts of the world with a transposable element (tr1). We also tested for genetic differences in ankyrin motifs (ank2 and pk1) which have been used to classify wPip strains into five worldwide groups (wPip1–wPip5) that vary in compatibility with each other based on experimental crosses. We found a mixture of both widely distributed and site specific genotypes based on presence or absence of WO prophage and transposable

  6. Human impacts on large benthic foraminifers near a densely populated area of Majuro Atoll, Marshall Islands.

    Science.gov (United States)

    Osawa, Yoko; Fujita, Kazuhiko; Umezawa, Yu; Kayanne, Hajime; Ide, Yoichi; Nagaoka, Tatsutoshi; Miyajima, Toshihiro; Yamano, Hiroya

    2010-08-01

    Human impacts on sand-producing, large benthic foraminifers were investigated on ocean reef flats at the northeast Majuro Atoll, Marshall Islands, along a human population gradient. The densities of dominant foraminifers Calcarina and Amphistegina declined with distance from densely populated islands. Macrophyte composition on ocean reef flats differed between locations near sparsely or densely populated islands. Nutrient concentrations in reef-flat seawater and groundwater were high near or on densely populated islands. delta(15)N values in macroalgal tissues indicated that macroalgae in nearshore lagoons assimilate wastewater-derived nitrogen, whereas those on nearshore ocean reef flats assimilate nitrogen from other sources. These results suggest that increases in the human population result in high nutrient loading in groundwater and possibly into nearshore waters. High nutrient inputs into ambient seawater may have both direct and indirect negative effects on sand-producing foraminifers through habitat changes and/or the collapse of algal symbiosis. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Radionuclide concentrations in fish and invertebrates from Bikini Atoll

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Jokela, T.A.; Brunk, J.A.

    1988-01-01

    As in other global studies, 137 Cs was found in the highest concentrations in edible flesh of all species of fish and in the lowest concentrations in the bone or liver. The mean concentration of 137 Cs in muscle of reef fish from the southern part of the atoll is comparable to the global-fallout concentration measured in market samples of fish collected from Chicago, IL, USA, in 1982. Strontium-90 is associated generally with non-edible parts of fish, such as bone or viscera. Twenty-five to fifty percent of the total body burden of 60 Co is accumulated in the muscle tissue; the remainder is distributed among the liver, skin, and viscera. The mean concentration of 60 Co in fish has been decreasing at a rate faster than radiological decay alone. Most striking is the range of 207 Bi concentrations among different species of fish collected at the same time and place. Highest concentrations of 207 Bi were consistently detected in the muscle and other tissues of goatfish and some of the pelagic lagoon fish. In other reef fish, such as mullet, surgeonfish, and parrotfish, 207 Bi was usually below detection limits by gamma spectrometry. Over 70% of the whole-body activity of 207 Bi in goatfish is associated with the muscle tissue, whereas less than 5% is found in the muscle of mullet and surgeonfish. Neither 239+240 Pu nor 241 Am is accumulated significantly in the muscle tissue of any species of fish. Apparently, 238 Pu is in a more readily available form for accumulation by fishes than 239+240 Pu. Based on a daily ingestion rate of 200 g of fish flesh, dose rates to individuals through the fish-food ingestion pathway are well below current Federal guidelines. 24 refs., 1 fig., 27 tabs

  8. Resolving high-frequency internal waves generated at an isolated coral atoll using an unstructured grid ocean model

    Science.gov (United States)

    Rayson, Matthew D.; Ivey, Gregory N.; Jones, Nicole L.; Fringer, Oliver B.

    2018-02-01

    We apply the unstructured grid hydrodynamic model SUNTANS to investigate the internal wave dynamics around Scott Reef, Western Australia, an isolated coral reef atoll located on the edge of the continental shelf in water depths of 500,m and more. The atoll is subject to strong semi-diurnal tidal forcing and consists of two relatively shallow lagoons separated by a 500 m deep, 2 km wide and 15 km long channel. We focus on the dynamics in this channel as the internal tide-driven flow and resulting mixing is thought to be a key mechanism controlling heat and nutrient fluxes into the reef lagoons. We use an unstructured grid to discretise the domain and capture both the complex topography and the range of internal wave length scales in the channel flow. The model internal wave field shows super-tidal frequency lee waves generated by the combination of the steep channel topography and strong tidal flow. We evaluate the model performance using observations of velocity and temperature from two through water-column moorings in the channel separating the two reefs. Three different global ocean state estimate datasets (global HYCOM, CSIRO Bluelink, CSIRO climatology atlas) were used to provide the model initial and boundary conditions, and the model outputs from each were evaluated against the field observations. The scenario incorporating the CSIRO Bluelink data performed best in terms of through-water column Murphy skill scores of water temperature and eastward velocity variability in the channel. The model captures the observed vertical structure of the tidal (M2) and super-tidal (M4) frequency temperature and velocity oscillations. The model also predicts the direction and magnitude of the M2 internal tide energy flux. An energy analysis reveals a net convergence of the M2 energy flux and a divergence of the M4 energy flux in the channel, indicating the channel is a region of either energy transfer to higher frequencies or energy loss to dissipation. This conclusion is

  9. Swell-generated Set-up and Infragravity Wave Propagation Over a Fringing Coral Reef: Implications for Wave-driven Inundation of Atoll Islands

    Science.gov (United States)

    Cheriton, O. M.; Storlazzi, C. D.; Rosenberger, K. J.; Quataert, E.; van Dongeren, A.

    2014-12-01

    The Republic of the Marshall Islands is comprised of 1156 islands on 29 low-lying atolls with a mean elevation of 2 m that are susceptible to sea-level rise and often subjected to overwash during large wave events. A 6-month deployment of wave and tide gauges across two shore-normal sections of north-facing coral reef on the Roi-Namur Island on Kwajalein Atoll was conducted during 2013-2014 to quantify wave dynamics and wave-driven water levels on the fringing coral reef. Wave heights and periods on the reef flat were strongly correlated to the water levels. On the fore reef, the majority of wave energy was concentrated in the incident band (5-25 s); due to breaking at the reef crest, however, the wave energy over the reef flat was dominated by infragravity-band (25-250 s) motions. Two large wave events with heights of 6-8 m at 15 s over the fore reef were observed. During these events, infragravity-band wave heights exceeded the incident band wave heights and approximately 1.0 m of set-up was established over the innermost reef flat. This set-up enabled the propagation of large waves across the reef flat, reaching maximum heights of nearly 2 m on the innermost reef flat adjacent to the toe of the beach. XBEACH models of the instrument transects were able to replicate the incident waves, infragravity waves, and wave-driven set-up across the reef when the hydrodynamic roughness of the reef was correctly parameterized. These events led to more than 3 m of wave-driven run-up and inundation of the island that drove substantial morphological change to the beach face.

  10. Radiation-induced risk of resettling Bikini atoll. Final report, November 7, 1981-May 28, 1982

    International Nuclear Information System (INIS)

    Kohn, H.I.; Dreyer, N.A.

    1982-01-01

    The Department of Energy (DOE) has concluded that the Bikini atoll is unsafe for resettlement. In response to the Bikinians' request for an independent review, we have examined the following DOE findings: (a) radionuclide contamination of Eneu and Bikini Islands, (b) radiation dosage to those who might resettle the islands, and (c) risks to the health of such settlers. We are in practical agreement with the DOE estimates. Resettlement of either island in 1983 would lead to a range of annual or 30-year cumulative doses that exceed the Federal Radiation Council (FRC) guides for the general population, but not those for occupation exposure. By 2013 resettlement of Eneu probably would be permissible. The principal source of radiation dose is local food, especially coconut, owing to contamination of the soil by cesium-137. A precise estimate of dose is impossible. The availability of imported foods would lessen local food consumption, but not sufficiently to meet the FRC guides for the general population. The 30-year cumulative index dose is 61 (25-122) rem for Bikini, and about 8 (3-16) rem for Eneu

  11. Colonization and growth of crustose coralline algae (Corallinales, Rhodophyta on the Rocas Atoll

    Directory of Open Access Journals (Sweden)

    Alexandre Bigio Villas Bôas

    2005-12-01

    Full Text Available Crustose coralline algae play a fundamental role in reef construction all over the world. The aims fo this study were to identify and estimate the abundance of the dominant crustose coralline algae in shallow reef habitats, measuring their colonization, growth rates and productivity. Crusts sampled from different habitats were collected on leeward and windward reefs. Discs made of epoxy putty were fixed on the reef surface to follow coralline colonization and discs containing the dominant coralline algae were fixed on different habitats to measure the crusts' marginal growth. The primary production experiments followed the clear and dark bottle method for dissolved oxygen reading. Porolithon pachydermum was confirmed as the dominant crustose coralline alga on the Rocas Atoll. The non-cryptic flat form of P. pachydermum showed a faster growth rate on the leeward than on the windward reef. This form also had a faster growth rate on the reef crest (0.05 mm.day-1 than on the reef flat (0.01 mm.day-1. The cryptic protuberant form showed a trend, though not significant, towards a faster growth rate on the reef crest and in tidal pools than on the reef flat. Colonization was, in general, very slow as compared to that presented by other reef studies. P. pachydermum was a productive crust both in non-cryptic and cryptic habitats.As algas calcárias incrustantes exercem um papel fundamental na construção de recifes ao redor do mundo. Neste trabalho os objetivos foram: identificar e estimar a abundância da alga calcária incrustante dominante nas partes rasas do recife, verificando suas taxas de colonização, crescimento e produtividade. Crostas de diferentes habitats foram estudadas em locais a barlavento e sotavento. Discos feitos com massa epóxi foram fixados na superfície do recife para acompanhar a colonização das algas calcárias e discos contendo a alga calcária dominante foram fixados em diferentes habitats para medir o crescimento de suas

  12. An assessment of non-communicable diseases, diabetes, and related risk factors in the Republic of the Marshall Islands, Kwajelein Atoll, Ebeye Island: a systems perspective.

    Science.gov (United States)

    Ichiho, Henry M; Seremai, Johannes; Trinidad, Richard; Paul, Irene; Langidrik, Justina; Aitaoto, Nia

    2013-05-01

    Non-communicable diseases (NCD) have been declared a health emergency in the US-affiliated Pacific Islands (USAPI). This assessment, funded by the National Institutes of Health, was conducted on Ebeye Island of Kwajelein Atoll, Republic of the Marshall Islands (RMI) to describe the burdens due to selected NCD (diabetes, heart disease, hypertension, stroke, chronic kidney disease); assess the system of service capacity and activities for service delivery, data collection, and reporting; and identify the key issues that need to be addressed. Findings reveal that the risk factors of poor diet, lack of physical activity, and lifestyle behaviors lead to overweight and obesity and subsequent NCD that impact the morbidity and mortality of the population. Population survey of the RMI show that 62.5% of the total population is overweight or obese with a dramatic increase from the 15-24 year old (10.6%) and the 25-64 year old (41.9%) age groups. The leading causes of death were septicemia, renal failure, pneumonia, cancer, and myocardial infarction. Other findings show gaps in the system of administrative, clinical, and support services to address these NCD. All health care in Ebeye is provided in one setting and there is collaboration, coordination, and communication among medical and health care providers. The Book of Protocols for the Kwajalein Atoll Health Care Bureau provides the guidelines, standards, and policy and procedures for the screening, diagnosis, and management of diabetes and other NCDs. Based on these findings, priority issues and problems to be addressed for the administrative, clinical, and data systems were identified.

  13. Formation and adjustment of typhoon-impacted reef islands interpreted from remote imagery: Nadikdik Atoll, Marshall Islands

    Science.gov (United States)

    Ford, Murray R.; Kench, Paul S.

    2014-06-01

    In 1905, a devastating typhoon hit Nadikdik Atoll (5°54‧ N and 172°09‧ E) in the southern Marshall Islands. Evidence suggests that large sections of reef islands on Nadikdik were overwashed and destroyed. Comparison of aerial photographs taken in 1945 and modern satellite imagery provides a unique record of the geomorphic adjustment of islands after the typhoon. Between 1945 and 2010 the vegetated area of islands on Nadikdik grew from 0.74 to 0.90 km2. Observed changes to Nadikdik reef islands manifested through a range of styles and were largely accretionary. Of note, the formation of a new island was tracked from an embryonic deposit to a fully vegetated and stable island over a 61 year period. Similarly, a number of previously discrete islands have agglomerated and formed a single larger island. These changes were rapid and indicate that reef island formation can occur quickly. Evidence suggests that despite the typhoon occurring over a century ago the geomorphic adjustment of islands is still on-going.

  14. Lipid composition of water and surface sediments in Takapoto atoll lagoon (French Polynesia)

    Science.gov (United States)

    Saliot, A.; Bouloubassi, I.; Lorre-Boireau, A.; Trichet, J.; Poupet, P.; Charpy, L.

    1994-11-01

    Dissolved, particulate and sedimentary lipid compounds were analyzed in samples collected in May 1988 at three sites in the lagoon of the closed atoll of Takapoto (Tuamotu archipelago, French Polynesia). The study provides background information dealing with water quality and the nature and concentration of lipids. Non-aromatic hydrocarbons and fatty acids were isolated from lipids and analyzed by gas chromatography/mass spectrometry. Non-aromatic hydrocarbon concentrations did not exceed 1000 ng l-1 in water, and 2300 ng g-1 in surface sediments and are among the lowest encountered in pristine marine environments. No noticeable petroleum pollution was evidenced in the lagoon. Nevertheless, traces of petroleum-derived compounds were detected at the central site for both surface and deep water. Total fatty acid concentrations varied in the range 6.3 14.4 μg l-1 for the particulate phase and in the range 0.5 3.2 μg l-1 for the dissolved phase. The molecular fingerprints of fatty acids and hydrocarbons evidenced a predominant algal, and to a lesser extent microbial, origin of the organic matter present in water and sediments. Mono- and polyunsaturated fatty acids, which are essential components for animal metabolism, were identified in noticeable amounts in suspended matter (1.8 4.6 μg l-1), and at highly variable levels in the dissolved phase (0.08 1.21 μg l-1).

  15. Bikini Atoll Rehabilitation Committee Report no. 4 Status March 31, 1986. Submitted to the U.S. Congress, House and Senate Committees on Interior Appropriations, pursuant to House Report 99-450, Department of Interior Account no. TT-1580X08, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-07-01

    The principal findings of Report No. 4, Bikini Atoll Rehabilitation Committee (March 31, 1986) are as follows: (1) On the basis of the Federal protective action guide (ionizing radiation) and an Environmental Assessment, Eneu may be resettled now. The calculation of the planning dose for the estimation of radiation risk is given in detail. (2) Three principal methods for decontamination control are being studied in field trials at Bikini Atoll -- removal of top soil, treatment with potassium salt, and irrigation with sea water. The latter two, still in an early experimental stage, give promise of being cheaper and ecologically superior to excavation, but the details and limits of their practical application remain to be established. (3) The important socio-economic factors that affect resettlement planning for the Bikinians are reviewed. Prominent among them is a population growth rate of 5% per annum. Sketch plans to serve as models for the resettlement community are discussed. (author)

  16. Bikini Atoll Rehabilitation Committee Report no. 4 Status March 31, 1986. Submitted to the U.S. Congress, House and Senate Committees on Interior Appropriations, pursuant to House Report 99-450, Department of Interior Account no. TT-1580X08, Washington, DC

    International Nuclear Information System (INIS)

    1986-01-01

    The principal findings of Report No. 4, Bikini Atoll Rehabilitation Committee (March 31, 1986) are as follows: (1) On the basis of the Federal protective action guide (ionizing radiation) and an Environmental Assessment, Eneu may be resettled now. The calculation of the planning dose for the estimation of radiation risk is given in detail. (2) Three principal methods for decontamination control are being studied in field trials at Bikini Atoll -- removal of top soil, treatment with potassium salt, and irrigation with sea water. The latter two, still in an early experimental stage, give promise of being cheaper and ecologically superior to excavation, but the details and limits of their practical application remain to be established. (3) The important socio-economic factors that affect resettlement planning for the Bikinians are reviewed. Prominent among them is a population growth rate of 5% per annum. Sketch plans to serve as models for the resettlement community are discussed. (author)

  17. Concetration and Distribution of Depleted Uranium (DU) and Beryllium (Be) in Soil and Air on Illeginni Island at Kwajalein Atoll after the Final Land-Impact Test

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W L; Hamilton, T F; Martinelli, R E; Gouveia, F J; Kehl, S R; Lindman, T R; Yakuma, S C

    2010-04-22

    Re-entry vehicles on missiles launched from Vandenberg Air Force base in California re-enter at the Western Test Range, the Regan Test Site (RTS) at Kwajalein Atoll. An Environmental Assessment (EA) was written at the beginning of the program to assess potential impact of DU and Be, the major RV materials of interest from a health and environmental perspective, for both ocean and land impacts. The chemical and structural form of Be and DU in RVs is such that they are insoluble in soil water and seawater. Thus, they are not toxic to plant life on the isalnd (no soil to plant uptake.) Similarly, due to their insolubility in sea water there is no uptake of either element by fish, mollusks, shellfish, sea mammals, etc. No increase in either element has been observed in sea life around Illeginnin Island where deposition of DU and Be has occured. The critical terrestrial exposure pathway for U and Be is inhalation. Concentration of both elements in air over the test period (1989 to 2006) is lower by a factor of nearly 10,000 than the most restrictive U.S. guideline for the general public. Uranium concentrations in air are also lower by factors of 10 to 100 than concentrations of U in air in the U.S. measured by the EPA (Keith et al., 1999). U and Be concentrations in air downwind of deposition areas on Illeginni Island are essentially indistinguishable from natural background concentrations of U in air at the atolls. Thus, there are no health related issues associated with people using the island.

  18. Concetration and Distribution of Depleted Uranium (DU) and Beryllium (Be) in Soil and Air on Illeginni Island at Kwajalein Atoll after the Final Land-Impact Test

    International Nuclear Information System (INIS)

    Robison, W.L.; Hamilton, T.F.; Martinelli, R.E.; Gouveia, F.J.; Kehl, S.R.; Lindman, T.R.; Yakuma, S.C.

    2010-01-01

    Re-entry vehicles on missiles launched from Vandenberg Air Force base in California re-enter at the Western Test Range, the Regan Test Site (RTS) at Kwajalein Atoll. An Environmental Assessment (EA) was written at the beginning of the program to assess potential impact of DU and Be, the major RV materials of interest from a health and environmental perspective, for both ocean and land impacts. The chemical and structural form of Be and DU in RVs is such that they are insoluble in soil water and seawater. Thus, they are not toxic to plant life on the isalnd (no soil to plant uptake.) Similarly, due to their insolubility in sea water there is no uptake of either element by fish, mollusks, shellfish, sea mammals, etc. No increase in either element has been observed in sea life around Illeginnin Island where deposition of DU and Be has occured. The critical terrestrial exposure pathway for U and Be is inhalation. Concentration of both elements in air over the test period (1989 to 2006) is lower by a factor of nearly 10,000 than the most restrictive U.S. guideline for the general public. Uranium concentrations in air are also lower by factors of 10 to 100 than concentrations of U in air in the U.S. measured by the EPA (Keith et al., 1999). U and Be concentrations in air downwind of deposition areas on Illeginni Island are essentially indistinguishable from natural background concentrations of U in air at the atolls. Thus, there are no health related issues associated with people using the island.

  19. Concurrent Sr/Ca Ratios and Bomb Test 14C Records from a Porites evermanni Colony on Kure Atoll: SST, Climate Change, Ocean Circulation and Management Applications

    Science.gov (United States)

    Covarrubias, S.; Potts, D.; Siciliano, D.; Andrews, A.; Franks, R.

    2013-12-01

    Coral reefs near their latitudinal and ecological limits may be affected disproportionately by global climate changes, especially by changing sea surface temperatures (SST's). One such reef is Kure Atoll, the northernmost reef in the Hawaiian chain. Kure Atoll experiences dramatic temperature and seasonal differences throughout the year. Tracking these fluctuations is important for understanding recent physical forces affecting coral growth in such marginal reefs, and for predicting likely responses to future climate and oceanic changes. We used Sr/Ca ratios of a 50cm Porites evermanni coral core collected in Kure (September 2002) as a SST proxy for reconstructing a temperature timescale spanning the length of the core (~62 years). After cutting a 5 mm thick slab through the center growth axis and X-raying it to identify annual density banding, we extracted 4 equally-spaced samples from each annual increment to quantify, seasonal, inter-annual, and decadal SST patterns. We measured Sr and Ca concentrations by Inductively Coupled Plasma-Optical Emission Spectroscopy (ICP-OES). We then converted Sr/Ca ratios (mmol/mol) to SST using published equations, and calibrated the more recent SST estimates against satellite-based SST imagery and instrumental records from Midway Atoll (ca. 90 km to SE). We coupled the ICP-OES data with Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS) scans along the core to provide higher temporal resolution for interpreting intra-seasonal and inter-seasonal trends. Higher resolution of temperature dating can help us interpret strong inter-seasonal changes not readily seen with low resolution measurements, giving us the ability to track temperature anomalies at interannual and decadal timescales, such as El Niño/Southern Oscillation or La Niña/North Pacific Decadal Oscillation. Further, the SST signature from the Sr/Ca analyses are being used in conjunction with bomb radiocarbon signals in order to establish a complete

  20. Numerical simulation of passive tracer dispersion in the pacific ocean from Mururoa atoll (French Polynesia); Etude numerique de la dispersion d`un traceur dans le pacifique sud depuis l`atoll de Mururoa

    Energy Technology Data Exchange (ETDEWEB)

    Rancher, J.; Lazar, A.; Maes, Ch.

    1996-12-01

    In order to evaluate, on a Tropical South Pacific scale over 10 years, the consequences of an hypothetic radionuclide releases to the ocean from French Nuclear test sites, a series of numerical simulations was carried out. Tracer advection and diffusion terms were computed by a dispersion model without taking into account radioactive decay and biological interactions. Ocean dynamics and turbulent mixing coefficients were derived from a Ocean General circulation Model using annual average climatological fields. A punctual release with unit activity concentration throughout the depth showed the existence of two major directions of propagation from Mururoa atoll: one toward the Eastern Pacific when releases originated from 100-150 meters or less, and the other Westward if release depth is greater. The maximum concentrations which may possibly reach the continental South Pacific coastline originated from released points located in the 350 meters depth zone. Another experiment showed that an punctual release yields higher concentrations than the continuous release of an equivalent quantity over 10 years; two punctual releases were carried out at the characteristic depth of 5 m and 364 m: maximum concentrations decrease by factors of 10 000 and 1000 over ten years. A comparison is made with the surface release study of Ribbe and Tomczak (1990), despite a significant discrepancy in propagation direction, the order of magnitude for concentrations is comparable. (author).

  1. Atoll groundwater movement and its response to climatic and sea-level fluctuations

    Science.gov (United States)

    Oberle, Ferdinand; Swarzenski, Peter W.; Storlazzi, Curt

    2017-01-01

    Groundwater resources of low-lying atoll islands are threatened due to short-term and long-term changes in rainfall, wave climate, and sea level. A better understanding of how these forcings affect the limited groundwater resources was explored on Roi-Namur in the Republic of the Marshall Islands. As part of a 16-month study, a rarely recorded island-overwash event occurred and the island’s aquifer’s response was measured. The findings suggest that small-scale overwash events cause an increase in salinity of the freshwater lens that returns to pre-overwash conditions within one month. The overwash event is addressed in the context of climate-related local sea-level change, which suggests that overwash events and associated degradations in freshwater resources are likely to increase in severity in the future due to projected rises in sea level. Other forcings, such as severe rainfall events, were shown to have caused a sudden freshening of the aquifer, with salinity levels retuning to pre-rainfall levels within three months. Tidal forcing of the freshwater lens was observed in electrical resistivity profiles, high-resolution conductivity, groundwater-level well measurements and through submarine groundwater discharge calculations. Depth-specific geochemical pore water measurements further assessed and confirmed the distinct boundaries between fresh and saline water masses in the aquifer. The identification of the freshwater lens’ saline boundaries is essential for a quantitative evaluation of the aquifers freshwater resources and help understand how these resources may be impacted by climate change and anthropogenic activities.

  2. Atoll Groundwater Movement and Its Response to Climatic and Sea-Level Fluctuations

    Directory of Open Access Journals (Sweden)

    Ferdinand K. J. Oberle

    2017-08-01

    Full Text Available Groundwater resources of low-lying atoll islands are threatened due to short-term and long-term changes in rainfall, wave climate, and sea level. A better understanding of how these forcings affect the limited groundwater resources was explored on Roi-Namur in the Republic of the Marshall Islands. As part of a 16-month study, a rarely recorded island-overwash event occurred and the island’s aquifer’s response was measured. The findings suggest that small-scale overwash events cause an increase in salinity of the freshwater lens that returns to pre-overwash conditions within one month. The overwash event is addressed in the context of climate-related local sea-level change, which suggests that overwash events and associated degradations in freshwater resources are likely to increase in severity in the future due to projected rises in sea level. Other forcings, such as severe rainfall events, were shown to have caused a sudden freshening of the aquifer, with salinity levels retuning to pre-rainfall levels within three months. Tidal forcing of the freshwater lens was observed in electrical resistivity profiles, high-resolution conductivity, groundwater-level well measurements and through submarine groundwater discharge calculations. Depth-specific geochemical pore water measurements further assessed and confirmed the distinct boundaries between fresh and saline water masses in the aquifer. The identification of the freshwater lens’ saline boundaries is essential for a quantitative evaluation of the aquifers freshwater resources and help understand how these resources may be impacted by climate change and anthropogenic activities.

  3. Sediment studies at Bikini Atoll part 3. Inventories of some long-lived gamma-emitting radionuclides associated with lagoon surface sediments

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.

    1997-12-01

    Surface sediment samples were collected during 1979 from 87 locations in the lagoon at Bikini Atoll. The collections were made to better define the concentrations and distribution of long-lived radionuclides associated with the bottom material and to show what modifications occurred to the composition of the surface sediment from the nuclear testing program conducted by the United States at the Atoll between 1946 and 1958. This is the last of three reports on Bikini sediment studies. In this report, we discuss the concentrations and inventories of the residual long-lived gamma-emitting radionuclides in sediments from the lagoon. The gamma-emitting radionuclides detected most frequently in sediments collected in 1979, in addition to Americium-241 ({sup 241}Am) (discussed in the second report of this series), included Cesium-137 ({sup 137}Cs), Bismuth-207 ({sup 207}Bi), Europium-155 ({sup 155}Eu), and Cobalt-60 ({sup 60}Co). Other man-made, gamma-emitting radionuclides such as Europium-152,154 ({sup 152,154}Eu), Antimony-125 ({sup 125}Sb), and Rhodium-101,102m ({sup 101,102m}Rh) were occasionally measured above detection limits in sediments near test site locations. The mean inventories for {sup 137}Cs, {sup 207}Ei, {sup 155}Eu, and {sup 60}Co in the surface 4 cm of the lagoon sediment to be 1.7, 0.56, 7.76, and 0.74 TBq, respectively. By June 1997, radioactive decay would reduce these values to 1.1, 0.38, 0.62, and 0.07 TBq, respectively. Some additional loss results from a combination of different processes that continuously mobilize and return some amount of the radionuclides to the water column. The water and dissolved constituents are removed from the lagoon through channels and exchange with the surface waters of the north equatorial Pacific Ocean. Highest levels of these radionuclides are found in surface deposits lagoonward of the Bravo Crater. Lowest concentrations and inventories are associated with sediment lagoonward of the eastern reef. The quantities in

  4. Amount and type of derelict gear from the declining black pearl oyster aquaculture in Ahe atoll lagoon, French Polynesia.

    Science.gov (United States)

    Andréfouët, Serge; Thomas, Yoann; Lo, Cedrik

    2014-06-15

    Pearl oyster aquaculture is a major activity in French Polynesia atoll lagoons. After the economic decline that characterized the last decade, concerns recently rose about discarded installations and materials that supported aquaculture practices and by facilities abandoned after they had to close their activities. In May 2013, a first inventory of the type and amount of pearl farms derelict gear (PFDG) was achieved on 47 sites in Ahe lagoon. Surveys were conducted within and outside the boundaries of aquaculture concessions. Twenty types of PFDG littered the lagoon floor and the water column. The most impacted areas were near abandoned grafting houses with up to nine types of PFDG. Forty-five percent of the sites were impacted, including outside concessions. While management authorities are fully aware of the problem, this first assessment is a wake-up call to stimulate the cleaning of lagoons, enhance awareness among farmers, and identify potential ecological consequences on lagoon ecosystems. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atoll

    International Nuclear Information System (INIS)

    Noshkin, V. E.; Robison, W. L.

    1998-01-01

    Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the United States as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 Mt (Mt TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for 10's of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently about 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway is dominated by

  6. Ingestão de plástico pelo atobá-mascarado, Sula dactylatra Lesson, 1831, na Reserva Biológica do Atol das Rocas, RN, Brasil

    Directory of Open Access Journals (Sweden)

    Erich de Freitas Mariano

    2012-08-01

    Full Text Available http://dx.doi.org/10.5007/2175-7925.2012v25n4p285   Partículas plásticas constituem um dos poluentes mais comuns no ambiente marinho e atingem inclusive regiões com baixa densidade populacional humana. Frequentemente, essas partículas são ingeridas por diversos organismos marinhos, ocasionando problemas no trato digestivo, que podem culminar no enfraquecimento e morte do animal. Em um estudo acerca da alimentação de 631 Atobás-mascarados, Sula dactylatra, na Reserva Biológica do Atol das Rocas, foram encontradas partículas plásticas no conteúdo estomacal de quatro indivíduos adultos. Os artefatos plásticos encontrados constituíam-se de um plástico transparente, um pedaço de rótulo de garrafa de água mineral, dois pedaços de plástico preto e um pedaço rígido pequeno e vermelho. O fluxo de embarcações, tanto pesqueiras quanto turísticas, no entorno da ReBio Atol das Rocas pode ser a fonte de origem das peças plásticas tanto nos conteúdos estomacais quanto os encontrados nas ilhas da reserva, evidenciando que ações antropogênicas já atingem áreas isoladas, as quais deveriam ter um elevado grau de proteção da biodiversidade. Diversas medidas podem ser tomadas para evitar eventos deletérios na biota marinha, porém há uma grande dificuldade em evitar o descarte de lixo proveniente de navios pesqueiros e de turismo, além dos materiais vindos do continente, sendo necessário um incremento nos esforços de conscientização e fiscalização.

  7. Gross and microscopic morphology of lesions in Cnidaria from Palmyra Atoll, Central Pacific

    Science.gov (United States)

    Williams, Gareth J.; Work, Thierry M.; Aeby, Greta S.; Knapp, Ingrid S.; Davy, Simon K.

    2011-01-01

    We conducted gross and microscopic characterizations of lesions in Cnidaria from Palmyra Atoll, Central Pacific. We found growth anomalies (GA) to be the most commonly encountered lesion. Cases of discoloration and tissue loss were rare. GAs had a focal or multi-focal distribution and were predominantly nodular, exophytic, and umbonate. In scleractinians, the majority of GAs manifested as hyperplasia of the basal body wall (52% of cases), with an associated absence or reduction of polyp structure (mesenteries and filaments, actinopharynx and tentacles), and depletion of zooxanthellae in the gastrodermis of the upper body wall. In the soft corals Sinularia sp. and Lobophytum sp., GAs exclusively manifested as prominent hyperplasia of the coenenchyme with an increased density of solenia. In contrast to scleractinians, soft coral GAs displayed an inflammatory and necrotizing component with marked edema of the mesoglea, accompanied by infiltrates of variably-sized granular amoebocytes. Fungi, algae, sponges, and Crustacea were present in some scleractinian GAs, but absent in soft coral GAs. Fragmentation of tissues was a common finding in Acropora acuminata and Montipora cf. dilatata colonies with tissue loss, although no obvious causative agents were seen. Discoloration in the zoanthid, Palythoa tuberculosa, was found to be the result of necrosis, while in Lobophytum sp. discoloration was the result of zooxanthellar depletion (bleaching). Soft corals with discoloration or tissue loss showed a marked inflammatory response, however no obvious causative organisms were seen. Lesions that appeared similar at the gross level were revealed to be distinct by microscopy, emphasizing the importance of histopathology.

  8. ''Numerical simulation of passive tracer dispersion in the pacific ocean from Mururoa atoll (French Polynesia)''

    International Nuclear Information System (INIS)

    Rancher, J.; Lazar, A.; Maes, Ch.

    1996-12-01

    In order to evaluate, on a Tropical South Pacific scale over 10 years, the consequences of an hypothetic radionuclide releases to the ocean from French Nuclear test sites, a series of numerical simulations was carried out. Tracer advection and diffusion terms were computed by a dispersion model without taking into account radioactive decay and biological interactions. Ocean dynamics and turbulent mixing coefficients were derived from a Ocean General circulation Model using annual average climatological fields. A punctual release with unit activity concentration throughout the depth showed the existence of two major directions of propagation from Mururoa atoll: one toward the Eastern Pacific when releases originated from 100-150 meters or less, and the other Westward if release depth is greater. The maximum concentrations which may possibly reach the continental South Pacific coastline originated from released points located in the 350 meters depth zone. Another experiment showed that an punctual release yields higher concentrations than the continuous release of an equivalent quantity over 10 years; two punctual releases were carried out at the characteristic depth of 5 m and 364 m: maximum concentrations decrease by factors of 10 000 and 1000 over ten years. A comparison is made with the surface release study of Ribbe and Tomczak (1990), despite a significant discrepancy in propagation direction, the order of magnitude for concentrations is comparable. (author)

  9. Evaluating the potential for near-shore bathymetry on the Majuro Atoll, Republic of the Marshall Islands, using Landsat 8 and WorldView-3 imagery

    Science.gov (United States)

    Poppenga, Sandra K.; Palaseanu-Lovejoy, Monica; Gesch, Dean B.; Danielson, Jeffrey J.; Tyler, Dean J.

    2018-04-16

    Satellite-derived near-shore bathymetry (SDB) is becoming an increasingly important method for assessing vulnerability to climate change and natural hazards in low-lying atolls of the northern tropical Pacific Ocean. Satellite imagery has become a cost-effective means for mapping near-shore bathymetry because ships cannot collect soundings safely while operating close to the shore. Also, green laser light detection and ranging (lidar) acquisitions are expensive in remote locations. Previous research has demonstrated that spectral band ratio-based techniques, commonly called the natural logarithm approach, may lead to more precise measurements and modeling of bathymetry because of the phenomenon that different substrates at the same depth have approximately equal ratio values. The goal of this research was to apply the band ratio technique to Landsat 8 at-sensor radiance imagery and WorldView-3 atmospherically corrected imagery in the coastal waters surrounding the Majuro Atoll, Republic of the Marshall Islands, to derive near-shore bathymetry that could be incorporated into a seamless topobathymetric digital elevation model of Majuro. Attenuation of light within the water column was characterized by measuring at-sensor radiance and reflectance at different depths and calculating an attenuation coefficient. Bathymetric lidar data, collected by the U.S. Naval Oceanographic Office in 2006, were used to calibrate the SDB results. The bathymetric lidar yielded a strong linear relation with water depths. The Landsat 8-derived SDB estimates derived from the blue/green band ratio exhibited a water attenuation extinction depth of 6 meters with a coefficient of determination R2=0.9324. Estimates derived from the coastal/red band ratio had an R2=0.9597. At the same extinction depth, SDB estimates derived from WorldView-3 imagery exhibited an R2=0.9574. Because highly dynamic coastal shorelines can be affected by erosion, wetland loss, hurricanes, sea-level rise, urban

  10. A dose assessment for a U.S. nuclear test site -- Bikini Atoll

    International Nuclear Information System (INIS)

    Robison, W.L.; Bogen, K.T.; Conrado, C.L.

    1993-07-01

    On March 1, 1954, a nuclear weapon test, code-named BRAVO, conducted at Bikini Atoll in the northern Marshall Islands contaminated the major residence island. Here the authors provide a radiological dose assessment for the main residence island, Bikini, using extensive radionuclide concentration data derived from analysis of food crops, ground water, cistern water, fish and other marine species, animals, air, and soil collected at Bikini Island. The unique composition of coral soil greatly alters the relative contribution of cesium-137 and strontium-90 to the total estimated dose relative to expectations based on North American and European soils. Cesium-137 produces 96% of the estimated dose for returning residents, mostly through uptake from the soil to terrestrial food crops but also from external gamma exposure. The estimated maximum annual effective dose is 4.4 mSv y -1 when imported foods, which are now an established part of the diet, are available. The 30-, 50-, and 70-y integral effective doses are 10 cSv, 14 cSv, and 16 cSv, respectively. An analysis of interindividual variability in 0- to 30-y expected integral dose indicates that 95% of Bikini residents would have expected doses within a factor of 3.4 above and 4.8 below the population-average value. A corresponding uncertainty analysis showed that after about 5 y of residence, the 95% confidence limits on population-average dose would be ±35% of its expected value. The authors have evaluated various countermeasures to reduce 137 Cs in food crops. Treatment with potassium reduces the uptake of 137 Cs into food crops, and therefore the ingestion dose, to less than 10% of pretreatment levels and has essentially no negative environmental consequences

  11. The radiological situation at the atolls of Mururoa and Fangataufa. Technical report. V. 5. Transport of radioactive material within the marine environment

    International Nuclear Information System (INIS)

    1998-08-01

    The report discusses the modeling of the transport of radionuclides through the marine environment after their release from the atolls of Mururoa and Fangataufa. Modeling included mixing within the lagoons, and transport to the shores of neighbouring islands and distant continents of radioactive material released into the lagoons from sediments and from underground sources (from discharge directly to the ocean through the flanks of the carbonate caps of the atolls). For the purposes of the modelling, the area around the source of radioactivity (i.e. the point at which radionuclides are released into the marine environment) was divided into three major zones: a) the near field (the lagoons); b) the regional field (broadly, the area of French Polynesia); and c) the far field (the South Pacific beyond the regional field). The methodology adopted in this study can be summarized as follows: 1. A model of the mixing of water in the lagoons was developed. This model was used to estimate the radionuclide concentrations in the lagoons for given releases into the lagoons, and the flow rates of radionuclides from the lagoons into the surrounding ocean. 2. The release rates of radionuclides from the lagoon sediments were assessed, leading to estimates of the release rates of plutonium 137 Cs, 90 Sr and tritium from the lagoons to the oceans as a function of time. 3. A model was developed to predict the movement of sediment between the lagoons and the ocean. Estimates were made of the amount of sediment, and the corresponding quantity of plutonium leaving the lagoons annually under average weather conditions, or as consequence of a severe storm. 4. Three compartment models were used to model dispersion of radionuclides in the regional field. These models cover different areas with different resolutions, and each has particular strengths and weaknesses. Taken together, they give an indication of the likely uncertainty in the dispersion estimates, and improve the robustness of

  12. Ingested plastic as a route for trace metals in Laysan Albatross (Phoebastria immutabilis) and Bonin Petrel (Pterodroma hypoleuca) from Midway Atoll.

    Science.gov (United States)

    Lavers, Jennifer L; Bond, Alexander L

    2016-09-15

    Seabirds are declining faster than any other group of birds, with plastic ingestion and associated contaminants linked to negative impacts on marine wildlife, including >170 seabird species. To provide quantitative data on the effects of plastic pollution, we sampled feathers and stomach contents from Laysan Albatross (Phoebastria immutabilis) and Bonin Petrel (Pterodroma hypoleuca) on Midway Atoll, North Pacific Ocean, and assessed our ability to detect change over time by synthesizing previous studies. Between 25 and 100% of fledglings exceed international targets for plastic ingestion by seabirds. High levels of ingested plastic were correlated with increased concentrations of chlorine, iron, lead, manganese, and rubidium in feathers. The frequency of plastic ingestion by Laysan Albatross and concentration of some elements in both species is increasing, suggesting deterioration in the health of the marine environment. Variability in the frequency of plastic ingestion by Laysan Albatross may limit their utility as an indicator species. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Tidal flushing and wind driven circulation of Ahe atoll lagoon (Tuamotu Archipelago, French Polynesia) from in situ observations and numerical modelling

    International Nuclear Information System (INIS)

    Dumas, F.; Le Gendre, R.; Thomas, Y.; Andréfouët, S.

    2012-01-01

    Hydrodynamic functioning and water circulation of the semi-closed deep lagoon of Ahe atoll (Tuamotu Archipelago, French Polynesia) were investigated using 1 year of field data and a 3D hydrodynamical model. Tidal amplitude averaged less than 30 cm, but tide generated very strong currents (2 m s −1 ) in the pass, creating a jet-like circulation that partitioned the lagoon into three residual circulation cells. The pass entirely flushed excess water brought by waves-induced radiation stress. Circulation patterns were computed for climatological meteorological conditions and summarized with stream function and flushing time. Lagoon hydrodynamics and general overturning circulation was driven by wind. Renewal time was 250 days, whereas the e-flushing time yielded a lagoon-wide 80-days average. Tide-driven flush through the pass and wind-driven overturning circulation designate Ahe as a wind-driven, tidally and weakly wave-flushed deep lagoon. The 3D model allows studying pearl oyster larvae dispersal in both realistic and climatological conditions for aquaculture applications.

  14. Description and epizootiology of Babesia poelea n. sp. in brown boobies (Sula leucogaster (Boddaert)) on Sand Island, Johnston Atoll, Central Pacific

    Science.gov (United States)

    Work, Thierry M.; Rameyer, Robert

    1997-01-01

    We describe a new species of piroplasm from brown boobies (Sula leucogaster) on Sand Island, Johnston Atoll National Wildlife Refuge, central Pacific. Mean parasitemia in adults and chicks was less than 1%, with the parasitemia in chicks significantly greater than in adults. There was no significant relation between the age of chicks and the degree of parasitemia. Parasitized red cells and red cell nuclei were significantly smaller than those of unparasitized cells, and infected birds appeared clinically normal. Prevalence of the parasite in chicks (54%) was significantly greater than in adults (13%), and the geographic distribution of parasitized chicks was skewed toward the eastern end of Sand Island. On the basis of morphologic characteristics, we named it Babesia poelea. The specific name is a concatenation of the Hawaiian names for dark (po'ele) and booby ('a). This is the second documentation of an endemic avian hemoparasite in seabirds from the central Pacific.

  15. Independent Verification Survey of the Clean Coral Storage Pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project

    International Nuclear Information System (INIS)

    Wilson-Nichols, M.J.; Egidi, P.V.; Roemer, E.K.; Schlosser, R.M.

    2000-01-01

    f I The Oak Ridge National Laboratory (ORNL) Environmental Technology Section conducted an independent verification (IV) survey of the clean storage pile at the Johnston Atoll Plutonium Contaminated Soil Remediation Project (JAPCSRP) from January 18-25, 1999. The goal of the JAPCSRP is to restore a 24-acre area that was contaminated with plutonium oxide particles during nuclear testing in the 1960s. The selected remedy was a soil sorting operation that combined radiological measurements and mining processes to identify and sequester plutonium-contaminated soil. The soil sorter operated from about 1990 to 1998. The remaining clean soil is stored on-site for planned beneficial use on Johnston Island. The clean storage pile currently consists of approximately 120,000 m3 of coral. ORNL conducted the survey according to a Sampling and Analysis Plan, which proposed to provide an IV of the clean pile by collecting a minimum number (99) of samples. The goal was to ascertain wi th 95% confidence whether 97% of the processed soil is less than or equal to the accepted guideline (500-Bq/kg or 13.5-pCi/g) total transuranic (TRU) activity

  16. Environmental Assessment for Conventional Strike Missile Demonstration

    Science.gov (United States)

    2010-08-01

    impact Preferred Alternative flight path, Kwajalein, Likiep, Ailuk, Taka , and Utirik Atolls, as well as Jemo Islet, might be affected (see Figure 2-5...For the BOA impact Alternative flight path, Bikar, Taka , and Utirik Atolls might be affected. Census records from 1999 indicate 527 residents on...Likiep Atoll, 513 on Ailuk Atoll, 433 on Utirik Atoll; and none on Bikar and Taka Atolls or on Jemo Islet (RMI Economic Policy, Planning, and Statistics

  17. Sediment studies at Bikini Atoll part 1. distribution of fine and coarse components in surface sediments

    International Nuclear Information System (INIS)

    Noshkin, V. E.; Eagle, R.J.; Robison, W.L.

    1997-01-01

    In 1979, 21 years after the moratorium on nuclear testing in the Marshall Islands, surface sediment samples (to depths of 2 and 4 cm) were collected from 87 locations over the floor of Bikini lagoon. The main purpose for the collections was to map the distribution of long- lived man-made radionuclides associated with the bottom material. In addition the samples were processed to estimate the fraction of fine and coarse components to show what modifications occurred since the sediment composition was first described in samples collected before testing in 1946. In this report a comparison is made of the amount and distribution of fine material associated with the lagoon surface sediment before and after the testing of nuclear devices. Nuclear testing produced more finely divided material in-the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. Five cratering events at Bikini Atoll generated sufficient material to account for the inventory of new fine material found over the bottom surface of the lagoon. Although the fraction of fine material in the bottom sediments was altered by the nuclear events, the combined processes of formation, transport and deposition were not sufficiently dynamic to alter the geographical features of the major sedimentary components over most of the lagoon floor

  18. Sediment studies at Bikini Atoll part 1. distribution of fine and coarse components in surface sediments

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V. E.; Eagle, R.J.; Robison, W.L.

    1997-01-01

    In 1979, 21 years after the moratorium on nuclear testing in the Marshall Islands, surface sediment samples (to depths of 2 and 4 cm) were collected from 87 locations over the floor of Bikini lagoon. The main purpose for the collections was to map the distribution of long- lived man-made radionuclides associated with the bottom material. In addition the samples were processed to estimate the fraction of fine and coarse components to show what modifications occurred since the sediment composition was first described in samples collected before testing in 1946. In this report a comparison is made of the amount and distribution of fine material associated with the lagoon surface sediment before and after the testing of nuclear devices. Nuclear testing produced more finely divided material in-the surface sediment layer over large areas of the lagoon and especially in regions of the lagoon and reef adjacent to test sites. Five cratering events at Bikini Atoll generated sufficient material to account for the inventory of new fine material found over the bottom surface of the lagoon. Although the fraction of fine material in the bottom sediments was altered by the nuclear events, the combined processes of formation, transport and deposition were not sufficiently dynamic to alter the geographical features of the major sedimentary components over most of the lagoon floor.

  19. The application of PIT tags to measure transport of detrital coral fragments on a fringing reef: Majuro Atoll, Marshall Islands

    Science.gov (United States)

    Ford, Murray R.

    2014-06-01

    Passive integrated transponder (PIT) tags are a radio-frequency identification device widely used as a machine-readable identification tool in fisheries research. PIT tags have also been employed, to a lesser extent, to track the movement of gravel-sized clasts within fluvial and coastal systems. In this study, PIT tags were inserted into detrital coral fragments and used to establish source-sink transport pathways on a fringing reef on Majuro Atoll in the Marshall Islands. Results suggest the transport of gravel-sized material on the inter-tidal reef flat is exclusively across-reef towards the lagoon. Considerable variation in the distance travelled by fragments was observed. Fragments were largely intact and visually recognisable after almost 5 months on the reef flat. However, the branches of some recovered fragments had broken off and corallite abrasion was observed in recovered fragments. This study indicates that PIT tags are an inexpensive and powerful new addition to the suite of sediment transport and taphonomic tools for researchers working within coral reef systems.

  20. Radionuclide characterization and associated dose from long-lived radionuclides in close-in fallout delivered to the marine environment at Bikini and Enewetak Atolls

    International Nuclear Information System (INIS)

    Robison, W.L.; Noshkin, V.E.

    1999-01-01

    Between June 1946 and October 1958, Enewetak and Bikini Atolls were used by the US as testing grounds for 66 nuclear devices. The combined explosive yield from these tests was 107 million t (million t TNT equivalents). This testing produced close-in fallout debris that was contaminated with quantities of radioactive fission and particle activated products, and unspent radioactive nuclear fuel that entered the aquatic environment of the atolls. Today, the sediments in the lagoons are reservoirs for tens of TBq of the transuranics and some long-lived fission and activation products. The larger amounts of contamination are associated with fine and coarse sediment material adjacent to the locations of the high yield explosions. Radionuclides are also distributed vertically in the sediment column to various depths in all regions of the lagoons. Concentrations greater than fallout background levels are found in filtered water sampled over several decades from all locations and depths in the lagoons. This is a direct indication that the radionuclides are continuously mobilized to solution from the solid phases. Of particular importance is the fact that the long-lived radionuclides are accumulated to different levels by indigenous aquatic plants and organisms that are used as food by resident people. One might anticipate finding continuous high contamination levels in many of the edible marine organisms from the lagoons, since the radionuclides associated with the sediments are not contained and are available to the different organisms in a relatively shallow water environment. This is not the case. We estimate that the radiological dose from consumption of the edible parts of marine foods at Enewetak and Bikini is presently approximately 0.05% of the total 50-year integral effective dose from all other exposure pathways that include ingestion of terrestrial foods and drinking water, external exposure and inhalation. The total radiological dose from the marine pathway is

  1. Dose assessment, radioecology, and community interaction at former nuclear test sites

    International Nuclear Information System (INIS)

    Robison, W.L.

    1994-11-01

    The US conducted a nuclear testing program at Bikini and Enewetak Atolls in the Marshall Islands from 1946 through 1958. A total of 66 nuclear devices were tested--23 at Bikini Atoll (total yield of 77 megatons) and 43 at Enewetak Atoll (total yield of 33 megatons). This resulted in contamination of many of the islands at each atoll. The BRAVO test (yield 15 megatons) on March 1, 1954 contaminated several atolls to the east of Bikini Atoll some of which were inhabited. The author has conducted an experimental, monitoring, and dose assessment program at atolls in the northern Marshall Islands for the past 20 years. The goals have been to: (1) determine the radiological conditions at the atolls; (2) provide dose assessments for resettlement options and alternate living patterns; (3) develop and evaluate remedial measures to reduce the dose to people reinhabiting the atolls; and (4) discuss the results with each of the communities and the Republic of the Marshall Islands government officials to help them understand the data as a basis for resettlement decisions. The remaining radionuclides at the atolls that contribute any significant dose are 137 Cs, 90 Sr, 239+240 Pu, and 241 Am

  2. Phylogenetic analysis of a microbialite-forming microbial mat from a hypersaline lake of the Kiritimati atoll, Central Pacific.

    Science.gov (United States)

    Schneider, Dominik; Arp, Gernot; Reimer, Andreas; Reitner, Joachim; Daniel, Rolf

    2013-01-01

    On the Kiritimati atoll, several lakes exhibit microbial mat-formation under different hydrochemical conditions. Some of these lakes trigger microbialite formation such as Lake 21, which is an evaporitic, hypersaline lake (salinity of approximately 170‰). Lake 21 is completely covered with a thick multilayered microbial mat. This mat is associated with the formation of decimeter-thick highly porous microbialites, which are composed of aragonite and gypsum crystals. We assessed the bacterial and archaeal community composition and its alteration along the vertical stratification by large-scale analysis of 16S rRNA gene sequences of the nine different mat layers. The surface layers are dominated by aerobic, phototrophic, and halotolerant microbes. The bacterial community of these layers harbored Cyanobacteria (Halothece cluster), which were accompanied with known phototrophic members of the Bacteroidetes and Alphaproteobacteria. In deeper anaerobic layers more diverse communities than in the upper layers were present. The deeper layers were dominated by Spirochaetes, sulfate-reducing bacteria (Deltaproteobacteria), Chloroflexi (Anaerolineae and Caldilineae), purple non-sulfur bacteria (Alphaproteobacteria), purple sulfur bacteria (Chromatiales), anaerobic Bacteroidetes (Marinilabiacae), Nitrospirae (OPB95), Planctomycetes and several candidate divisions. The archaeal community, including numerous uncultured taxonomic lineages, generally changed from Euryarchaeota (mainly Halobacteria and Thermoplasmata) to uncultured members of the Thaumarchaeota (mainly Marine Benthic Group B) with increasing depth.

  3. Phylogenetic analysis of a microbialite-forming microbial mat from a hypersaline lake of the Kiritimati atoll, Central Pacific.

    Directory of Open Access Journals (Sweden)

    Dominik Schneider

    Full Text Available On the Kiritimati atoll, several lakes exhibit microbial mat-formation under different hydrochemical conditions. Some of these lakes trigger microbialite formation such as Lake 21, which is an evaporitic, hypersaline lake (salinity of approximately 170‰. Lake 21 is completely covered with a thick multilayered microbial mat. This mat is associated with the formation of decimeter-thick highly porous microbialites, which are composed of aragonite and gypsum crystals. We assessed the bacterial and archaeal community composition and its alteration along the vertical stratification by large-scale analysis of 16S rRNA gene sequences of the nine different mat layers. The surface layers are dominated by aerobic, phototrophic, and halotolerant microbes. The bacterial community of these layers harbored Cyanobacteria (Halothece cluster, which were accompanied with known phototrophic members of the Bacteroidetes and Alphaproteobacteria. In deeper anaerobic layers more diverse communities than in the upper layers were present. The deeper layers were dominated by Spirochaetes, sulfate-reducing bacteria (Deltaproteobacteria, Chloroflexi (Anaerolineae and Caldilineae, purple non-sulfur bacteria (Alphaproteobacteria, purple sulfur bacteria (Chromatiales, anaerobic Bacteroidetes (Marinilabiacae, Nitrospirae (OPB95, Planctomycetes and several candidate divisions. The archaeal community, including numerous uncultured taxonomic lineages, generally changed from Euryarchaeota (mainly Halobacteria and Thermoplasmata to uncultured members of the Thaumarchaeota (mainly Marine Benthic Group B with increasing depth.

  4. A remarkable sea-level drop and relevant biotic responses across the Guadalupian-Lopingian (Permian) boundary in low-latitude mid-Panthalassa: Irreversible changes recorded in accreted paleo-atoll limestones in Akasaka and Ishiyama, Japan

    Science.gov (United States)

    Kofukuda, Daisuke; Isozaki, Yukio; Igo, Hisayoshi

    2014-03-01

    The Capitanian (Upper Guadalupian) to Wuchiapingian (Lower Lopingian) shallow-marine limestones at Akasaka and Ishiyama in central Japan record unique aspects of the extinction-related Guadalupian-Lopingian boundary (G-LB) interval. The ca. 140 m-thick Akasaka Limestone consists of the Capitanian black limestone (Unit B; 112 m) and the Wuchiapingian light gray dolomitic limestone (Unit W; 21 m), with a black/white striped limestone (Unit S; 9 m) between them. The G-LB horizon is assigned at the base of Unit W, on the basis of the first occurrence of the Wuchiapingian fusulines. The Capitanian Unit B and the Wuchiapingian Unit W were deposited mostly in the subtidal zone of a lagoon, whereas the intervened Unit S and the lowermost Unit W were in the intertidal zone. A hiatus with a remarkable erosional feature was newly identified at the top of Unit S. These records indicate that the sea-level has dropped significantly around the G-LB to have exposed the top of the atoll complex above the sea-level. The Ishiyama Limestone, located ca. 10 km to the north of the Akasaka limestone, retains almost the same depositional records. The extinction of large-tested fusuline (Yabeina) and large bivalves (Alatoconchidae) occurred in the upper part of Unit B, and the overlying 20 m-thick limestone (the uppermost Unit B and Unit S) below the hiatus represents a unique barren interval. The upper half of the barren interval is more depleted in fossils than the lower half, and this likely represents a duration of the severest environmental stress(es) for the shallow-marine protists/animals on the mid-oceanic paleo-atoll complex. Small-tested fusulines re-appeared at the base of Unit W above the hiatus. These facts prove that the elimination of shallow-marine biota occurred during the Capitanian shallowing of Akasaka paleo-atoll before the subaerial exposure/erosion across the G-LB. The overall shallowing and the development of such a clear hiatus at the top of a mid-oceanic seamount

  5. The 2004 Indian Ocean Tsunami in Maldives: waves and disaster affected by shape of coral reefs and islands

    Science.gov (United States)

    Kan, H.; Ali, M.; Riyaz, M.

    2005-12-01

    In Maldives, 39 islands are significantly damaged among 200 inhabited islands and nearly a third of the Maldivian people are severely affected by the Indian Ocean Tsunami in 26 December 2004. We surveyed tsunami impact in 43 islands by measuring island topography and run-up height, interview to local people and mapping of the flooded and destructed areas. The differences in tsunami height and disaster corresponding to the atoll shape and island topography are observed. In the northern atolls, atoll rims consist of many ring-shaped reefs, i.e. miniature atolls called `faro', and interrupted many channels between them. The interrupted atoll rim may play an important role to reducing tsunami run-up height. Severe damage was not observed in the eastern coast of the islands. Beach ridge also contribute to the protection against tsunami. However, in some islands, houses beside the lagoon are damaged by backwashing floodwater from the lagoon. Water marks show the run-up height of -1.8m above MSL. The lagoon water-level seems to set-up by tsunami which permeates into the lagoon through the interrupted atoll rim. The disaster was severe at the southern atolls of Meemu, Thaa and Laamu. The higher run-up heights of up to 3.2m above MSL and enormous building damages were observed at the islands on the eastern atoll rims. The continuous atoll rim of these atolls may reinforce tsunami impact at the eastern islands. In addition, tsunami surge washed the islands totally because of low island topography without beach ridge. Significant floodwater from lagoon was not observed in these atolls. It seems the lagoon water-level was not set-up largely. The continuous atoll rim reduces the tsunami influence to the lagoon and the western side of the atolls. The continuity of atoll rim is probably the major factor to cause the difference in water movement, i.e. tsunami run-up and lagoon set-up, which affects the disaster in the islands. Beach ridge contribute to reduce the tsunami impact to

  6. PSI contribution to the IAEA study on the radiological situation at the atolls of Mururoa and Fangataufa

    International Nuclear Information System (INIS)

    Pfingsten, W.; Hadermann, J.

    1999-01-01

    Upon the definitive end of the French atomic bomb tests in the South Pacific, the International Atomic Energy Agency (IAEA) was asked to evaluate the radiological situation at the atolls of Mururoa and Fangataufa. The IAEA put up various working groups and invited PSI to participate in the group of geosphere radionuclide transport. Together with the other members of the Working Group, PSI developed models, performed calculations and assessed the radionuclide releases from the various sources and the transport of radionuclides through the geological layers. There were 137 underground sources at Mururoa and 10 at Fangataufa. Release via the groundwater has been assessed for radionuclides which were judged of potential importance, 35 in number. Certain nuclides, notably 3 H, 90 Sr, 137 Cs and 239 Pu were investigated in more detail. Data and, partially, model uncertainty was handled by varying the parameters and by comparing differing model concepts. In cases of lack of data ; assumptions were made such that nuclide fluxes are deemed to be overestimated. Calculated results could partially be checked against experimental information. Radionuclide concentrations observed at various test sites are consistent with results from the solution source term model. Calculated releases to the lagoon are generally consistent with measurements. The analysis of all test categories has shown that the radionuclide release to either the lagoon or the ocean is dominated by a few tests. (author)

  7. Radiological conditions at Naen, Yugui, Lomiulal, Kabelle and Mellu Islands in the northern half of Rongelap Atoll

    International Nuclear Information System (INIS)

    Robison, W.L.; Conrado, C.L.

    1996-03-01

    The data presented in the following tables is the total available for each northern island; they include both the data from the 1978 Northern Marshall Island Radiological Survey (NMIRS) and trips to Rongelap Atoll from 1986 through 1989. In one table we present the number of vegetation samples collected in the 1978 NMIRS and from 1986 through 1989. Again the majority of the 137 Cs data is from the 1986-1989 trips. We have not made additional analyses of 239+240 Pu, 241 Am and 90 Sr because the concentrations are very low and these radionuclides contribute less than 5% of an already very small dose. In another table we show the number of soil samples collected at each island in 1978 and the number collected since 1986. Most of the data are from 1986 through 1989. The major exception is 90 Sr where all of the data are from the 1978 NMIRS. We have done some additional Pu analyses of surface soils (0-5 cm depth) in the northern islands. A significant amount of new data for 137 Cs and 241 Am have been generated from the samples collected from 1986 through 1989. The data are presented in the form of summary tables, graphics, detailed appendices and aerial photographs of the islands with the sample locations marked. The identified sample locations from the 1978 NMIRS will be added later

  8. SAR Observation and Numerical Simulation of Internal Solitary Wave Refraction and Reconnection Behind the Dongsha Atoll

    Science.gov (United States)

    Jia, T.; Liang, J. J.; Li, X.-M.; Sha, J.

    2018-01-01

    The refraction and reconnection of internal solitary waves (ISWs) around the Dongsha Atoll (DSA) in the northern South China Sea (SCS) are investigated based on spaceborne synthetic aperture radar (SAR) observations and numerical simulations. In general, a long ISW front propagating from the deep basin of the northern SCS splits into northern and southern branches when it passes the DSA. In this study, the statistics of Envisat Advanced SAR (ASAR) images show that the northern and southern wave branches can reconnect behind the DSA, but the reconnection location varies. A previously developed nonlinear refraction model is set up to simulate the refraction and reconnection of the ISWs behind the DSA, and the model is used to evaluate the effects of ocean stratification, background currents, and incoming ISW characteristics at the DSA on the variation in reconnection locations. The results of the first realistic simulation agree with consecutive TerraSAR-X (TSX) images captured within 12 h of each other. Further sensitivity simulations show that ocean stratification, background currents, and initial wave amplitudes all affect the phase speeds of wave branches and therefore shift their reconnection locations while shapes and locations of incoming wave branches upstream of the DSA profoundly influence the subsequent propagation paths. This study clarifies the variation in reconnection locations of ISWs downstream of the DSA and reveals the important mechanisms governing the reconnection process, which can improve our understanding of the propagation of ISWs near the DSA.

  9. The flip-or-flop boutique: Marine debris on the shores of St Brandon's rock, an isolated tropical atoll in the Indian Ocean.

    Science.gov (United States)

    Bouwman, Hindrik; Evans, Steven W; Cole, Nik; Choong Kwet Yive, Nee Sun; Kylin, Henrik

    2016-03-01

    Isolated coral atolls are not immune from marine debris accumulation. We identified Southeast Asia, the Indian sub-continent, and the countries on the Arabian Sea as most probable source areas of 50 000 items on the shores of St. Brandon's Rock (SBR), Indian Ocean. 79% of the debris was plastics. Flip-flops, energy drink bottles, and compact fluorescent lights (CFLs) were notable item types. The density of debris (0.74 m(-)(1) shore length) is comparable to similar islands but less than mainland sites. Intact CFLs suggests product-facilitated long-range transport of mercury. We suspect that aggregated marine debris, scavenged by the islands from currents and gyres, could re-concentrate pollutants. SBR islets accumulated debris types in different proportions suggesting that many factors act variably on different debris types. Regular cleaning of selected islets will take care of most of the accumulated debris and may improve the ecology and tourism potential. However, arrangements and logistics require more study. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Calcium dynamics in microbialite-forming exopolymer-rich mats on the atoll of Kiritimati, Republic of Kiribati, Central Pacific.

    Science.gov (United States)

    Ionescu, D; Spitzer, S; Reimer, A; Schneider, D; Daniel, R; Reitner, J; de Beer, D; Arp, G

    2015-03-01

    Microbialite-forming microbial mats in a hypersaline lake on the atoll of Kiritimati were investigated with respect to microgradients, bulk water chemistry, and microbial community composition. O2, H2S, and pH microgradients show patterns as commonly observed for phototrophic mats with cyanobacteria-dominated primary production in upper layers, an intermediate purple layer with sulfide oxidation, and anaerobic bottom layers with sulfate reduction. Ca(2+) profiles, however, measured in daylight showed an increase of Ca(2+) with depth in the oxic zone, followed by a sharp decline and low concentrations in anaerobic mat layers. In contrast, dark measurements show a constant Ca(2+) concentration throughout the entire measured depth. This is explained by an oxygen-dependent heterotrophic decomposition of Ca(2+)-binding exopolymers. Strikingly, the daylight maximum in Ca(2+) and subsequent drop coincides with a major zone of aragonite and gypsum precipitation at the transition from the cyanobacterial layer to the purple sulfur bacterial layer. Therefore, we suggest that Ca(2+) binding exopolymers function as Ca(2+) shuttle by their passive downward transport through compression, triggering aragonite precipitation in the mats upon their aerobic microbial decomposition and secondary Ca(2+) release. This precipitation is mediated by phototrophic sulfide oxidizers whose action additionally leads to the precipitation of part of the available Ca(2+) as gypsum. © 2014 John Wiley & Sons Ltd.

  11. Phylogenetic and functional diversity of Bacteria and Archaea in a unique stratified lagoon, the Clipperton atoll (N Pacific).

    Science.gov (United States)

    Galand, Pierre E; Bourrain, Muriel; De Maistre, Emmanuel; Catala, Philippe; Desdevises, Yves; Elifantz, Hila; Kirchman, David L; Lebaron, Philippe

    2012-01-01

    The Clipperton lagoon in the North Pacific Ocean has been isolated from the surrounding sea for c. 160 years. It has a stratified water column that comprises an oxic and brackish upper water layer (mixolimnion) and a deep sulfuric anoxic saline layer (monimolimnion), separated by a steep pycnocline. Here, we test whether the Clipperton lagoon with its distinctive physico-chemical features, geographic isolation, recent water column stratification, and large nutrient input harbors original microbial communities. The combination of capillary electrophoresis single-strand polymorphism (CE-SSCP) fingerprinting and sequencing of cloned bacterial and archaeal 16S rRNA genes, and functional genes for methanogenesis (mcrA), methanotrophy (pmoA), and sulfate reduction (dsrAB), revealed that microbial communities and pathways were highly stratified down the water column. The mixolimnion contained ubiquitous freshwater clades of Alpha- and Betaproteobacteria, while the pycnocline contained mostly green sulfur bacteria (phylum Chlorobi). Sequences of the upper layers were closely related to sequences found in other aquatic ecosystems, suggesting that they have a strong potential for dispersal and colonization. In contrast, the monimolimnion contained new deeply branching bacterial divisions within the OP11 cluster and the Bacteroidetes, and was the most diverse of the layers. The unique environmental conditions characterizing the deep layers of the lagoon may explain the novelty of the microbial communities found at the Clipperton atoll.

  12. Climatic Constraints on Growth Rate and Geochemistry (Sr/Ca and U/Ca) of the Coral Siderastrea stellata in the Southwest Equatorial Atlantic (Rocas Atoll, Brazil)

    Science.gov (United States)

    Evangelista, H.; Sifeddine, A.; Corrège, T.; Servain, J.; Dassié, E. P.; Logato, R.; Cordeiro, R. C.; Shen, C.-C.; Le Cornec, F.; Nogueira, J.; Segal, B.; Castagna, A.; Turcq, B.

    2018-03-01

    Although relatively rare compared to similar latitudes in the Pacific or Indian Oceans, massive coral colonies are present in the Tropical/Equatorial Southwestern Atlantic Ocean. However, detailed geochemical compositions of these corals are still largely unknown. In this work, we present growth rates, Sr/Ca, and U/Ca ratios of the coral colony (Siderastrea stellata) sampled at Rocas Atoll, off the Brazilian coast. These variables are primarily affected by sea surface temperature (SST) at seasonal scale, and by wind stress at interannual scale, these results represent a broad new finding. A lower significance at the interannual time scale between Sr/Ca and U/Ca with respect to SST is attributed to the low SST amplitude closed to Equator. An investigation on the dependence of coral growth rates with respect to the "cloud shading effect" promoted by the Intertropical Convergence Zone (ITCZ) does not show significant influence. Additionally, rain seems to act on local geochemistry of Sr/Ca ratios and growth rate at the decadal scale.

  13. Dose assessment in the Marshall Islands

    International Nuclear Information System (INIS)

    Robison, William L.

    1978-01-01

    Bikini Atoll and Enewetak Atoll in the Marshall Islands were the sites of major U.S. weapons testing from 1948 through 1958. Both the Bikini and Knewetak people have expressed a desire to return to their native Atolls. In 1968 clean-up and resettlement of Bikini was begun. In 1972-73 the initial survey of Enewetak Atoll was conducted and clean-up began in 1977. Surveys have been conducted at both Atolls to establish the concentrations of radionuclides in the biota and to determine the external exposure rates. Subsequent to the surveys dose assessments have been made to determine the potential dose to returning (100) populations at both Atolls. This talk will include discussions of the relative importance of the critical exposure pathways (i.e., external exposure, inhalation, marine, terrestrial and drinking water), the predominant radionuclides contributing to the predicted doses for each pathway, the doses predicted for alternate living patterns, comparison to Federal Guidelines, the comparison between Atolls, some of the social problems created by adherence to Federal Guidelines and the follow-up research identified and initiated to help refine the dose assessments and better predict the long term use of the Atolls (86). (author)

  14. Terrestrial radiation measurements in Marshall Islands

    International Nuclear Information System (INIS)

    Gudiksen, P.H.

    1978-01-01

    With the prospect of habitation in the near future, radiological surveys were undertaken of Enewetak and Bikini Atolls to provide a basis for determining whether or not the atolls can be safely reinhabited. The surveys included all of the forty islands within Enewetak Atoll, but only the two principal islands, Bikini and Eneu Islands, of Bikini Atoll. These atolls were former U.S. nuclear weapons test sites in the Pacific. Integral parts of the surveys were the measurements of the distributions of radioactivity in the soil and the resulting gamma ray exposure rates for external dose estimation. Numerous soil samples were collected from both atolls for analysis by Ge (Li) gamma spectrometry and by wet chemistry techniques. At Enewetak Atoll the gamma exposure rates were measured by TLDs and a helicopter-borne array of Nal detectors, while at Bikini Atoll portable Nal detectors, pressurized ion-chambers, and TLDs were utilized. The predominant species measured in the soil samples collected from both atolls were 90 Sr, 239,240 Pu, 137 Cs and 60 Co with the latter two nuclides being the primary contributors to the gamma-ray exposure rates. The geographical distribution of the exposure rates measured on both atolls, was highly variable ranging from less than 1 μR/h on islands that had not been impacted radiologically by the testing program, to over 100 μR/h near weapon detonation sites. Thus, within Enewetak Atoll, the highest soil activities and gamma-ray exposure rates were measured on the northern islands, where the weapons testing had been most intense. Bikini Island exhibited contamination levels that were considerably higher than those on Eneu Island. Generally, the highest activity levels were observed within the island interiors or in proximity to ground zero sites, and could usually be related to the surrounding vegetation density. The island of Yvonne, within Enewetak Atoll, is the most severely contaminated land area. Particles containing as much as several

  15. Uncertainty analysis for an updated dose assessment for a US nuclear test site: Bikini Atoll

    International Nuclear Information System (INIS)

    Bogen, K.T.; Conrado, C.L.; Robison, W.L.

    1995-11-01

    A detailed analysis of uncertainty and interindividual variability in estimated doses was conducted for a rehabilitation scenario for Bikini Island at Bikini Atoll, in which the top 40 cm of soil would be removed in the housing and village area, and the rest of the island is treated with potassium fertilizer, prior to an assumed resettlement date of 1999. Predicted doses were considered for the following fallout-related exposure pathways: ingested Cesium-137 and Strontium-90, external gamma exposure, and inhalation and ingestion of Americium-241 + Plutonium-239+240. Two dietary scenarios were considered: (1) imported foods are available (IA), and (2) imported foods are unavailable (only local foods are consumed) (IUA). Corresponding calculations of uncertainty in estimated population-average dose showed that after ∼5 y of residence on Bikini, the upper and lower 95% confidence limits with respect to uncertainty in this dose are estimated to be approximately 2-fold higher and lower than its population-average value, respectively (under both IA and IUA assumptions). Corresponding calculations of interindividual variability in the expected value of dose with respect to uncertainty showed that after ∼5 y of residence on Bikini, the upper and lower 95% confidence limits with respect to interindividual variability in this dose are estimated to be approximately 2-fold higher and lower than its expected value, respectively (under both IA and IUA assumptions). For reference, the expected values of population-average dose at age 70 were estimated to be 1.6 and 5.2 cSv under the IA and IUA dietary assumptions, respectively. Assuming that 200 Bikini resettlers would be exposed to local foods (under both IA and IUA assumptions), the maximum 1-y dose received by any Bikini resident is most likely to be approximately 2 and 8 mSv under the IA and IUA assumptions, respectively

  16. Space schemes of ecological zonation and morphology of the atolls lagoons and reef complex of an oceanic archipelago of the Caribbean: San Andres and Providence (Colombia)

    International Nuclear Information System (INIS)

    Diaz M, Juan Manuel

    2005-01-01

    The oceanic atolls and reef-complexes of the Archipelago of San Andres and Providencia exhibit semi-enclosed to rather open lagoon basins, where various characteristic bottom habitats occur. Certain areas of the lagoon floor are covered by sediments, being in some settings vegetated by algae or sea grass, and other areas by coralline framework of different types according to the composition and dominance of coral species and to their morphology and level of reef development. This study seeks to determine the spatial distribution patterns of lagoon bottom habitats based on the analysis of gradients of most relevant physical factors. Patterns in the occurrence and abundance of most habitats became evident in relation with wave-energy level, water depth, and the occurrence of islands. Some morphological reef types are oriented in a preferential direction and show spatial arrangements of development that are presumably related to prevailing current speed and direction and wave exposure

  17. Concentration of Beryllium (Be) and Depleted Uranium (DU) in Marine Fauna and Sediment Samples from Illeginni and Boggerik Islands at Kwajalein Atoll

    International Nuclear Information System (INIS)

    Robison, W L; Hamilton, T F; Martinelli, R E; Kehl, S R; Lindman, T R

    2005-01-01

    Lawrence Livermore National Laboratory (LLNL) personnel have supported US Air Force (USAF) ballistic missile flight tests for about 15 years for Peacekeeper and Minuteman missiles launched at Vandenberg Air Force Base (VAFB). Associated re-entry vehicles (RV's) re-enter at Regan Test Site (RTS) at the US Army base at Kwajalein Atoll (USAKA) where LLNL has supported scoring, recovery operations for RV materials, and environmental assessments. As part of ongoing USAF ballistic missile flight test programs, LLNL is participating in an updated EA being written for flights originating at VFAB. Marine fauna and sediments (beach-sand samples) were collected by US Fish and Wildlife Service (USFWS), National Marine Fisheries Service (NMFS), and LLNL at Illeginni Island and Boggerik Island (serving as a control site) at Kwajalein Atoll. Data on the concentration of DU (hereafter, U) and Be in collected samples was requested by USFWS and NMFS to determine whether or not U and Be in RV's entering the Illeginni area are increasing U and Be concentrations in marine fauna and sediments. LLNL agreed to do the analyses for U and Be in support of the EA process and provide a report of the results. There is no statistically significant difference in the concentration of U and Be in six species of marine fauna from Illeginni and Boggerik Islands (p - 0.14 for U and p = 0.34 for Be). Thus, there is no evidence that there has been any increase in U and Be concentrations in marine fauna as a result of the missile flight test program. Concentration of U in beach sand at Illeginni is the same as soil and beach sand in the rest of the Marshall Islands and again reflects an insignificant impact from the flight test program. Beach sand from Illeginni has a mean concentration of Be higher than that from the control site, Boggeik Island. Seven of 21 samples from Ileginni had detectable Be. Four samples had a concentration of Be ranging from 4 to 7 ng g -1 (4 to 7 parts per billion (ppb)), one

  18. Reply to: Terry, J. and Goff, J. comment on “Late Cenozoic sea level and the rise of modern rimmed atolls” by Toomey et al. (2016), Palaeogeography, Palaeoclimatology, Palaeoecology 4 51: 73–83.

    Science.gov (United States)

    Toomey, Michael; Ashton, Andrew; Raymo, Maureen E.; Perron, J. Taylor

    2017-01-01

    We appreciate Terry and Goff's thoughtful comment in response to our proposed atoll development model. Flank collapse of reef-built slopes likely does affect plan-form atoll morphology in some locations and potentially poses a tsunami hazard to low-lying Pacific islands (Terry and Goff, 2013). However, given the often rapid rates of lagoon infill (> 1 mm/yr; Montaggioni, 2005), such failure events would likely need to be frequent and widespread in order to leave a morphologic imprint on modern western Pacific atoll lagoon depths. Few atoll flank collapse features have been dated but many of the arcuate bight-like structures (ABLS) identified could be inherited from scars incised into the initial volcanic edifice (e.g. Terry and Goff, 2013 and refs. therein) — submarine mass wasting has been extensively documented on young hotspot islands (e.g. Hawaiian Islands: Moore et al., 1989; Reunion: Oehler et al., 2008). Atolls in the Marshall Islands, where our main study site Enewetak Atoll is located, are likely ~ 50–100 million years old (Larson et al., 1995) and dating of adjacent deep-water turbidite aprons in the Nauru Basin (DSDP Site 462; Schlanger and Silva, 1986) suggests that large atoll flank collapse events have been relatively infrequent there since the mid-Miocene (wasting events, will be essential for exploring the plan-form and 3D shapes of atolls. To our knowledge, no quantitative model of long-term atoll development has explicitly linked lagoon restriction/sedimentation to episodic flank collapse events (e.g. Montaggioni et al., 2015; Paterson et al., 2006; Quinn, 1991; Warrlich et al., 2002). Testing Terry and Goff's proposed conceptual model for how rim failure processes affect atoll morphology in a numerical context will require deep drilling along arcuate bight-like structures, as well as adjacent, unaffected, rim and lagoon areas, in order quantify how often failures occur and how quickly the rim/lagoon is rebuilt afterwards. The model we present

  19. Report of the preliminary mission of radiological controls on the island of Mangareva and the atolls of Tureia and Hao (French Polynesia). Investigation performed by the CRIIRAD laboratory on the request of the inquiry Commission on consequences of atmospheric nuclear tests

    International Nuclear Information System (INIS)

    2006-01-01

    After a presentation of the objectives of the mission, and a summary of the undertaken actions on each site, this document gives some general information on radionuclides and on the sampling and analysis method. Then, it discusses the results obtained by radiological analyses and gives recommendations about the current radiological situation of the studied island and atolls. It shows that official assessment of radiation doses undergone by the French Polynesia population during the period atmospheric nuclear tests must be revised. It outlines the need of new exhaustive investigations on health consequences of these past exposures to ionizing radiation. Recommendations are formulated

  20. 76 FR 78309 - Hawaiian and Pacific Islands National Wildlife Refuge Complex; Wilderness Review and Legislative...

    Science.gov (United States)

    2011-12-16

    ... wilderness, and accomplish refuge purposes in a way that preserves wilderness character. Our policies on... Forest, Palmyra Atoll, Pearl Harbor, Rose Atoll, and Wake Atoll. These refuges are located in Hawai'i... preserves wilderness character in accordance with (1) the Refuges' respective CCPs; (2) regulations on...

  1. An updated dose assesment for resettlement options at Bikini atoll - A US nuclear test site

    International Nuclear Information System (INIS)

    Robison, W.L.; Bogen, K.T.; Conrado, C.L.

    1997-01-01

    There has been a continuing effort since 1977 to refine dose assessments for resettlement options at Bikini Atoll. Here we provide a radiological dose assessment for the main residence island, Bikini, using extensive radio nuclide concentration data derived from analysis of food crops, ground water, cistern water, fish and other marine species, animals, air, and soil collected at Bikini Island as part of our continuing research and monitoring program that began in 1978. The unique composition of coral soil greatly alters the relative contribution of 137 Cs and 90 Sr to the total estimated dose relative to expectations based on North American and European soils. Without counter measures, 137 Cs produces 96% of the estimated dose for returning residents, mostly through uptake from the soil to terrestrial food crops but also from external gamma exposure. The doses are calculated assuming a resettlement date of 1999. The estimated maximum annual effective dose for current island conditions is 4.0 mSv when imported foods, which are now an established part of the diet, are available. The 30-, 50-, and 70-y integral effective doses are 91 mSv, 130 mSv, and 150 mSv, respectively. A detailed uncertainty analysis for these dose estimates is presented in a companion paper in this issue. We have evaluated various countermeasures to reduce 137 Cs in food crops. Treatment with potassium reduces the uptake of 137 Cs into food crops, and therefore the ingestion dose, to about 5 % of pretreatment levels and has essentially no negative environmental consequences. We have calculated the dose for the rehabilitation scenario where the top 40 cm of soil is removed in the housing and village area, and the rest of the island is treated with potassium fertilizer; the maximum annual effective dose is 0.41 mSv and the 30-, 50-, and 70-y integral effective doses are 9.8 mSv, 14 mSv, and 16 mSv, respectively. 44 refs., 3 figs., 11 tabs

  2. Commercial Appropriation of a Person's Image: Wells V Atoll Media (Pty Ltd (Unreported 11961/2006 [2009] ZAWCHC 173 (9 November 2009

    Directory of Open Access Journals (Sweden)

    SJ Cornelius

    2011-05-01

    Full Text Available Our modern society has become transfixed with celebrity. Business people and marketers also endeavour to cash in on the popularity enjoyed by the stars and realise the value of associating merchandise or trademarks with the rich and famous. This leads to difficulties when the attributes of a person are apparently used without consent, which poses new questions to the law: should the law protect the individual against the unlawful use of his or her image? If so, to what extent should such protection be granted? These were some of the questions which the court had to answer in Wells v Atoll Media (Pty. The judgment in Wells has redefined the right to identity and provided some clarity on what the infringement of that right would amount to. When the attributes of a person are used without consent, the right to identity can be violated in one of four ways. A person's right to identity can be infringed upon if the attributes of that person are used without permission in a way which cannot be reconciled with the true image of the individual concerned, if the use amounts to the commercial exploitation of the individual, if it cannot be reconciled with generally accepted norms of decency, or if it violates the privacy of that person.

  3. Frequency distribution, isotopic composition and physical characterization of plutonium-bearing particles from the Fig-Quince zone on Runit Island, Enewetak Atoll

    International Nuclear Information System (INIS)

    Hamilton, T.F.; Martinelli, R.E.; Kehl, S.R.; Rivers, A.N.; Brown, T.A.; Tumey, S.J.; Jernstroeem, J.; Williams, R.W.

    2009-01-01

    Runit Island on Enewetak Atoll was very heavily impacted by the U.S. nuclear testing campaign in the northern Marshall Islands (1946-58). The primary source of contamination on Runit Island was the 1958 Quince safety test where a large quantity of device plutonium (Pu) was scattered over the area near the GZ. A second low-yield device was detonated on the same site 10 days later, further disturbing the soil and leaving behind a very heterogeneous pattern of contamination including milligram-size particles of plutonium. A limited cleanup of the Fig-Quince zone was carried out in 1979. During this period, the effectiveness of the cleanup operations was primarily evaluated on the basis of bulk soil concentration data with little consideration given to the heterogeneity and long-term material-, biological-, and environmental-specific impacts of residual high activity (hot) particle contamination. The aim of the present study was twofold; (i) to characterize the levels and distribution of residual contamination in the Fig-Quince zone, and (ii) to develop pertinent data on the frequency distribution, elemental and isotopic composition, and physico-chemical properties of hot particles isolated from surface soils from Fig-Quince with a view towards providing recommendations on the future management and possible cleanup of the site. Today, Runit Island remains under an administrative quarantine. (author)

  4. Distribution and sediment production of large benthic foraminifers on reef flats of the Majuro Atoll, Marshall Islands

    Science.gov (United States)

    Fujita, K.; Osawa, Y.; Kayanne, H.; Ide, Y.; Yamano, H.

    2009-03-01

    The distributions and population densities of large benthic foraminifers (LBFs) were investigated on reef flats of the Majuro Atoll, Marshall Islands. Annual sediment production by foraminifers was estimated based on population density data. Predominant LBFs were Calcarina and Amphistegina, and the population densities of these foraminifers varied with location and substratum type on reef flats. Both foraminifers primarily attached to macrophytes, particularly turf-forming algae, and were most abundant on an ocean reef flat (ORF) and in an inter-island channel near windward, sparsely populated islands. Calcarina density was higher on windward compared to leeward sides of ORFs, whereas Amphistegina density was similar on both sides of ORFs. These foraminifers were more common on the ocean side relative to the lagoon side of reef flats around a windward reef island, and both were rare or absent in nearshore zones around reef islands and on an ORF near windward, densely populated islands. Foraminiferal production rates varied with the degree to which habitats were subject to water motion and human influences. Highly productive sites (>103 g CaCO3 m-2 year-1) included an ORF and an inter-island channel near windward, sparsely populated islands, and a seaward area of a reef flat with no reef islands. Low-productivity sites (<10 g CaCO3 m-2 year-1) included generally nearshore zones of lagoonal reef flats, leeward ORFs, and a windward ORF near densely populated islands. These results suggest that the distribution and production of LBFs were largely influenced by a combination of natural environmental factors, including water motion, water depth, elevation relative to the lowest tidal level at spring tide, and the distribution of suitable substratum. The presence of reef islands may limit the distribution and production of foraminifers by altering water circulation in nearshore environments. Furthermore, increased anthropogenic factors (population and activities) may

  5. The zebrafish maternal-effect gene cellular atoll encodes the centriolar component sas-6 and defects in its paternal function promote whole genome duplication.

    Science.gov (United States)

    Yabe, Taijiro; Ge, Xiaoyan; Pelegri, Francisco

    2007-12-01

    A female-sterile zebrafish maternal-effect mutation in cellular atoll (cea) results in defects in the initiation of cell division starting at the second cell division cycle. This phenomenon is caused by defects in centrosome duplication, which in turn affect the formation of a bipolar spindle. We show that cea encodes the centriolar coiled-coil protein Sas-6, and that zebrafish Cea/Sas-6 protein localizes to centrosomes. cea also has a genetic paternal contribution, which when mutated results in an arrested first cell division followed by normal cleavage. Our data supports the idea that, in zebrafish, paternally inherited centrosomes are required for the first cell division while maternally derived factors are required for centrosomal duplication and cell divisions in subsequent cell cycles. DNA synthesis ensues in the absence of centrosome duplication, and the one-cycle delay in the first cell division caused by cea mutant sperm leads to whole genome duplication. We discuss the potential implications of these findings with regards to the origin of polyploidization in animal species. In addition, the uncoupling of developmental time and cell division count caused by the cea mutation suggests the presence of a time window, normally corresponding to the first two cell cycles, which is permissive for germ plasm recruitment.

  6. Better or worse? The role of solar photovoltaic (PV) systems in sustainable development. Case studies of remote atoll communities in Kiribati

    Energy Technology Data Exchange (ETDEWEB)

    Mala, Kirti; Schlaepfer, August; Pryor, Trevor [School of Electrical, Energy and Process Engineering, Murdoch University, Murdoch 6150 (Australia)

    2009-02-15

    The Republic of Kiribati, formerly known as the Gilbert Islands, is a Micronesian (One of the three groups of islands in the Pacific. The eight territories that make up Micronesia are Commonwealth of the Northern Mariana Islands, Federated States of Micronesia, Republic of Kiribati, Republic of the Marshall Islands, Republic of Nauru, Republic of Palau, Territory of Guam and Territory of Wake Island. The other two groups of islands in the Pacific are Melanesia and Polynesia) country in the Pacific. The energy sources utilised in Kiribati include petroleum products, biomass, solar energy and wind power. Solar energy was introduced in Kiribati in the early 1980s (Wade H. Survey of RESCO projects - prepared for OPRET, Fiji Department of Energy, 2003; p. 36). Currently, it makes a very insignificant (less than 1%) contribution to the total annual primary energy supply (South Pacific Regional Environment Programme (SPREP). Pacific Islands Renewable Energy Project (PIREP) - Pacific Regional Energy Assessment (PREA) 2004. Kiribati national report, Vol. 5, 2005). Solar energy in Kiribati is used mostly in the form of solar photovoltaic (PV) technologies for the provision of lighting and electricity. This study examines the role of PV technologies in the sustainable development process in Kiribati, with particular reference to remote atoll communities. Initial results from on-site surveys carried out are reported in this paper. These surveys have sought to identify the reasons why people use or do not use PV systems. (author)

  7. Cryptic species obscure introduction pathway of the blue Caribbean sponge (Haliclona (Soestella caerulea, (order: Haplosclerida to Palmyra Atoll, Central Pacific

    Directory of Open Access Journals (Sweden)

    Ingrid S. Knapp

    2015-08-01

    Full Text Available Cryptic species are widespread across the phylum Porifera making the identification of non-indigenous species difficult, an issue not easily resolved by the use of morphological characteristics. The widespread order Haplosclerida is a prime example due to limited and plastic morphological features. Here, we study the reported introduction of Haliclona (Soestella caerulea from the Caribbean to Palmyra Atoll via Hawaiʻi using morphological characteristics and genetic analyses based on one nuclear (18s rDNA and three mitochondrial (COI, the barcoding COI extension (COI ext. and rnl rDNA markers. Despite no clear division in lengths of the oxea spicules between the samples, both mtDNA and nDNA phylogenetic trees supported similar topologies resolving two distinct clades. Across the two clades, the concatenated mtDNA tree resolved twelve subclades, with the COI ext. yielding most of the variability between the samples. Low sequence divergence values (0.68% between two of the subclades indicate that the same species is likely to occur at Palmyra, Hawaiʻi and the Caribbean, supporting the hypothesis that H. caerulea was introduced to Palmyra from the Caribbean, although whether species came directly from the Caribbean to Palmyra or from Hawaiʻi remains unresolved. Conversely, the pattern of highly divergent cryptic species supports the notion that traditionally used spicule measurements are taxonomically unreliable in this group. This study illustrates how understanding the scale of within- as opposed to between-species level genetic variation is critical for interpreting biogeographic patterns and inferring the origins of introduced organisms.

  8. Uncertainty and variability in updated estimates of potential dose and risk at a US Nuclear Test Site - Bikini Atoll

    International Nuclear Information System (INIS)

    Bogen, K.T.; Conrado, C.L.; Robison, W.L.

    1997-01-01

    Uncertainty and interindividual variability were assessed in estimated doses for a rehabilitation scenario for Bikini Island at Bikini Atoll, in which the top 40 cm of soil would be removed in the housing and village area, and the rest of the island would be treated with potassium fertilizer, prior to an assumed resettlement date of 1999. Doses were estimated for ingested 137 Cs and 90 Sr, external gamma-exposure, and inhalation+ingestion of 241 Am + 239+240 Pu. Two dietary scenarios were considered: imported foods are available (IA); imported foods are unavailable with only local foods consumed (IUA). After ∼5 y of Bikini residence under either IA or IUA assumptions, upper and lower 95% confidence limits on interindividual variability in calculated dose were estimated to lie within a ∼threefold factor of its in population-average value; upper and lower 95% confidence limits on uncertainty in calculated dose were estimated to lie within a ∼twofold factor of its expected value. For reference, the expected values of population-average dose at age 70 y were estimated to be 16 and 52 mSv under IA and IUA dietary assumptions, respectively. Assuming that 200 Bikini resettlers would be exposed to local foods (under both IA and IUA assumptions), the maximum 1-y dose received by any Bikini resident is most likely to be approximately 2 and 8 mSv under the IA and IUA assumptions, respectively. Under the most likely dietary scenario, involving access to imported foods, this analysis indicates that it is most likely that no additional cancer fatalities (above those normally expected) would arise from the increased radiation exposures considered. 33 refs., 4 figs., 4 tabs

  9. The use of comparative 137Cs body burden estimates from environmental data/models and whole body counting to evaluate diet models for the ingestion pathway

    International Nuclear Information System (INIS)

    Robison, W.L.; Sun, C.

    1997-01-01

    Rongelap and Utirik Atolls were contaminated on 1 March 1954, by a U.S. nuclear test at Bikini Atoll code named BRAVO. The people at both atolls were removed from their atolls in the first few days after the detonation and were returned to their atolls at different times. Detailed studies have been carried out over the years by Lawrence Livermore National Laboratory (LLNL) to determine the radiological conditions at the atolls and estimate the doses to the populations. The contribution of each exposure pathway and radionuclide have been evaluated. All dose assessments show that the major potential contribution to the estimated dose is 137 Cs uptake via the terrestrial food chain. Brookhaven National Laboratory (BNL) has carried out an extensive whole body counting program at both atolls over several years to directly measure the 137 Cs body burden. Here we compare the estimates of the body burdens from the LLNL environmental method with body burdens measured by the BNL whole body counting method. The combination of the results from both methods is used to evaluate proposed diet models to establish more realistic dose assessments. Very good agreement is achieved between the two methods with a diet model that includes both local and imported foods. Other diet models greatly overestimate the body burdens (i.e., dose) observed by whole body counting. The upper 95% confidence limit of interindividual variability around the population mean value based on the environmental method is similar to that calculated from direct measurement by whole body counting. Moreover, the uncertainty in the population mean value based on the environmental method is in very good agreement with the whole body counting data. This provides additional confidence in extrapolating the estimated doses calculated by the environmental method to other islands and atolls. 46 refs., 8 figs., 5 tabs

  10. Northern Marshall Islands radiological survey: terrestrial food chain and total doses

    International Nuclear Information System (INIS)

    Robison, W.L.; Mount, M.E.; Phillips, W.A.; Conrado, C.A.; Stuart, M.L.; Stoker, C.E.

    1982-01-01

    A radiological survey was conducted from September through November of 1978 to assess the concentrations of persistent manmade radionuclides in the terrestrial and marine environments of 11 atolls and 2 islands in the Northern Marshall Islands. The survey consisted mainly of an aerial radiological reconnaissance to map the external gamma-ray exposure rates over the islands of each atoll. The logistical support for the entire survey was designed to accommodate this operation. As a secondary phase of the survey, shore parties collected appropriate terrestrial and marine samples to assess the radiological dose from pertinent food chains to those individuals residing on the atolls, who may in the future reside on some of the presently uninhabited atolls, or who collect food from these atolls. Over 5000 terrestrial and marine samples were collected for radionuclide analysis from 76 different islands. Soils, vegetation, indigenous animals, and cistern water and groundwater were collected from the islands. Reef and pelagic fish, clams, lagoon water, and sediments were obtained from the lagoons. The concentration data for 90 Sr, 137 Cs, 238 Pu, 239 240 Pu, and 241 Am in terrestrial food crops, fowl, and animals collected at the atolls or islands are summarized. An assessment of the total dose from the major exposure pathways including external gamma, terrestrial food chain including food products and drinking water, marine food chain, and inhalation is provided. Radiological doses at each atoll or island are calculated from the average radionuclide concentrations in the terrestrial foods, marine foods, etc. assuming the average daily intake for each food item

  11. Fallout deposition in the Marshall Islands from Bikini and Enewetak nuclear weapons tests.

    Science.gov (United States)

    Beck, Harold L; Bouville, André; Moroz, Brian E; Simon, Steven L

    2010-08-01

    Deposition densities (Bq m(-2)) of all important dose-contributing radionuclides occurring in nuclear weapons testing fallout from tests conducted at Bikini and Enewetak Atolls (1946-1958) have been estimated on a test-specific basis for 32 atolls and separate reef islands of the Marshall Islands. A complete review of various historical and contemporary data, as well as meteorological analysis, was used to make judgments regarding which tests deposited fallout in the Marshall Islands and to estimate fallout deposition density. Our analysis suggested that only 20 of the 66 nuclear tests conducted in or near the Marshall Islands resulted in substantial fallout deposition on any of the 23 inhabited atolls. This analysis was confirmed by the fact that the sum of our estimates of 137Cs deposition from these 20 tests at each atoll is in good agreement with the total 137Cs deposited as estimated from contemporary soil sample analyses. The monitoring data and meteorological analyses were used to quantitatively estimate the deposition density of 63 activation and fission products for each nuclear test, plus the cumulative deposition of 239+240Pu at each atoll. Estimates of the degree of fractionation of fallout from each test at each atoll, as well as of the fallout transit times from the test sites to the atolls were used in this analysis. The estimates of radionuclide deposition density, fractionation, and transit times reported here are the most complete available anywhere and are suitable for estimations of both external and internal dose to representative persons as described in companion papers.

  12. Measuring and Modeling Solute Transport in the Rootzone: Protecting the Receiving Water Environments of the Coral Atolls of Tonga

    Science.gov (United States)

    Clothier, B. E.; van der Velde, M.; Green, S. R.; Gee, G. W.; Manu, V.; Menoniti, V.; Vanclooster, M.

    2005-05-01

    Intensification of agriculture on the raised coral atolls of the Tongan archipelago, notably through squash-pumpkin production, has lead to increased use of agrichemicals. Agrichemicals, both fertilisers and pesticides, pose a risk to these fragile environments. Sustainable land-management practices are needed for small-island developing states. On Tongatapu, solutes leaving the rootzone of the squash can rapidly find their way to the underlying freshwater lenses. These lenses are hydraulically linked to the internal lagoon, and the fringing reefs. We have used buried, non-suction fluxmeters to monitor both the quantity and quality of drainage leaving the rootzone of squash. Fertiliser is traditionally applied at planting. During establishment of the squash in 2003, some 350 mm of rain fell, with 70 % of this leaving the rootzone of this permeable soil as drainage. The concentration of nitrate-N in the drainage water was measured at around 50 mg-N/L. All of the initial fertiliser dressing had been lost, along with N mineralised from the plowed-in grass. Pesticides are needed in humid tropical environments to control weeds, pests and diseases. These chemicals can leach though the rootzone to contaminate receiving waters. We modeled the transport and fate of the presticides used in squash production, and we developed a Decision Support Tool (DST). Our DST can be used to select the best pesticides for local conditions, to tailor practices for minimising leaching losses below the rootzone, and to avoid the build-up of residues in the soil. This project, funded by the European Union and NZAID, took a multi-disciplinary approach through measurement and modeling protocols. Our DST enabled us to engage the wider community and stakeholders. There has been increased awareness of the impacts and risks associated with productive land management in the fragile hydrological environments of this small-island developing state.

  13. A comparison of independently conducted dose assessments to determine compliance and resettlement options for the people of Rongelap Atoll

    International Nuclear Information System (INIS)

    Simon, S.L.; Robison, W.L.; Thorne, M.C.

    1997-01-01

    Rongelap Island was the home of Marshallese people numbering less than 120 in 1954; 67 were on the island and severely exposed to radioactive fallout from an atomic weapons test in March of that year. Those resident on Rongelap were evacuated 50 h after the test, returned 3 y later, then voluntarily left their home island in 1985 due to their ongoing fear of radiation exposure from residual radioactive contamination. Following international negotiations in 1991, a Memorandum of Understanding (NIOU) was signed in early 1992 between the Republic of the Marshall Islands Government, the Rongelap Atoll Local Government, the U.S. Department of Energy, and the U.S. Department of the Interior. In this MOU it was agreed that the Republic of the Marshall Islands, with the aid of the U.S. Department of Energy, would carry out independent dose assessments for the purpose of assisting and advising the Rongelap community on radiological issues related to a safe resettlement of Rongelap. In 1994, four independent assessments were reported, including one from each of the following entities: Marshall Islands Nationwide Radiological Study; Lawrence Livermore National Laboratory; an independent advisor from the United Kingdom (MCT); and a committee of the National Research Council. All four assessments concluded that possibly more than 25% of the adult population could exceed the 1 mSv y -1 dose level based on strict utilization of a local food diet. The purpose of this report is to summarize the methodology, assumptions, and findings from each of four assessments; to summarize the recommendations related to mitigation and resettlement options; to discuss unique programmatic aspects of the study; and to consider the implications of the findings to the future of the Rongelap people. 63 refs., 5 figs., 3 tabs

  14. Thyroid neoplasia in Marshall Islanders exposed to nuclear fallout

    International Nuclear Information System (INIS)

    Hamilton, T.E.; van Belle, G.; LoGerfo, J.P.

    1987-01-01

    We studied the risk of thyroid neoplasia in Marshall Islanders exposed to radioiodines in nuclear fallout from the 1954 BRAVO thermonuclear test. We screened 7266 Marshall Islanders for thyroid nodules; the islanders were from 14 atolls, including several southern atolls, which were the source of the best available unexposed comparison group. Using a retrospective cohort design, we determined the prevalence of thyroid nodularity in a subgroup of 2273 persons who were alive in 1954 and who therefore were potentially exposed to fallout from the BRAVO test. For those 12 atolls previously thought to be unexposed to fallout, the prevalence of thyroid nodules ranged from 0.9% to 10.6%. Using the distance of each atoll from the test site as a proxy for the radiation dose to the thyroid gland, a weighted linear regression showed an inverse linear relationship between distance and the age-adjusted prevalence of thyroid nodules. Distance was the strongest single predictor in logistic regression analysis. A new absolute risk estimate was calculated to be 1100 excess cases/Gy/y/1 X 10(6) persons (11.0 excess cases/rad/y/1 million persons), 33% higher than previous estimates. We conclude that an excess of thyroid nodules was not limited only to the two northern atolls but extended throughout the northern atolls; this suggests a linear dose-response relationship

  15. 5 CFR 591.205 - Which areas are nonforeign areas?

    Science.gov (United States)

    2010-01-01

    ... islands of the Samoa group east of longitude 171 degrees west of Greenwich, together with Swains Island...) Palmyra Atoll; (12) Territory of Guam; (13) United States Virgin Islands; (14) Wake Atoll; (15) Any small...

  16. Plutonium mobilization from sedimentary sources to solution in the marine environment

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.

    1979-01-01

    Inventories of plutonium radionuclides greatly in excess of global fallout levels persists in the benthic environments of Bikini and Eniwetok Atolls. It now appears that the atolls have reached a chemical steadystate condition with respect to the partitioning of 239+240 Pu between solution and solid phases of the environment. The mobilized 239+240 Pu has solute-like characteristics, passes rapidly and readily through dialysis membranes, has adsorption characteristics similar to those of fallout plutonium in the open ocean, and exists in solution primarily as some oxidized +5 or +6 chemical species. Water-column profiles of 239+240 Pu taken outside the atolls show a plutonium excess in the deep water mass. This remobilized 239+240 Pu possibly originates from the contaminated sediments previously deposited on the outer slopes of the atolls and surrounding basins

  17. 2006 EM300 and EM3002D Multibeam Sonar Data from Cruise Hi'ialakai HI-06-09 - Northwestern Hawaiian Islands and Main Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EM300 and EM3002D multibeam data were collected from 23 June to 20 July 2006 aboard NOAA Ship Hi'ialakai at Kure Atoll, Pearl and Hermes Atoll, Midway Island, and...

  18. Findings of the Marshall Islands nationwide radiological study

    International Nuclear Information System (INIS)

    McEwan, A.C.

    1996-01-01

    Full text: The Marshall Islands were affected by nuclear weapon tests carried out over the period 1946-1958, and particularly from the Bravo detonation on 1 March 1954, which deposited heavy fallout on the islands of Rongelap atoll about 100 miles to the east of Bikini. Surveys of residual radioactivity of the northern atolls of the Marshalls group had been carried out by the US Department of Energy, but continuing concerns about health effects of exposure to fallout, particularly thyroid disease, led the Marshall Islands government in 1989 to set up a study of residual radioactivity across the entire country. A study of residual radioactivity on all significant atolls and islands was carried out by ground surveys during 1990-94. The study was supervised by an international panel of 5 non US scientists. The measurements included portable gamma spectrometer measurements at points on a grid pattern, with associated soil samples and periodic soil profile and vegetation samples. From these measurements external exposure rates from deposited fallout have been calculated, and estimates made of the ingestion doses which might be received by resident populations consuming diets made up of differing amounts of locally produced foodstuffs. On the basis of a survey of dietary intake by a Rongelap community a current diet (containing 18% of foods from local sources) and a more traditional diet (75% from local sources) were used for comparison purposes. Measurements were made on 432 islands of the 29 atolls and 5 islands that make up the Marshalls group. Atolls in the latitude range 9-12 degrees north have Cs-137 soil concentrations which are elevated above levels expected from global fallout. Over 90% of the radiation dose from residual fallout is attributable to Cs-137, and arises primarily from dietary intake. Doses to actual or hypothetical residents are about 4 times greater for traditional as compared with current diets. For four atolls there are some islands where

  19. Journal of Earth System Science | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Keywords. Atoll garnet; eclogite; fluid infiltration; retrograde metamorphism; Ladakh Himalayas; Tso Morari Complex. Abstract. The eclogites of the Tso Morari Complex, Ladakh, NW Himalayas preserve both garnets with spectacular atoll textures, as well as whole porphyroblastic garnets. Whole garnets are euhedral, ...

  20. Enewetak fact book (a resume of pre-cleanup information)

    International Nuclear Information System (INIS)

    Bliss, W.

    1982-09-01

    The book contains a group of short treatises on the precleanup condition of the islands in Enewetak Atoll. Their purpose was to provide brief guidance to the radiological history and radiological condition of the islands for use in cleanup of the atoll

  1. An assessment of non-communicable diseases, diabetes, and related risk factors in the Republic of the Marshall Islands, Majuro Atoll: a systems perspective.

    Science.gov (United States)

    Ichiho, Henry M; deBrum, Ione; Kedi, Shra; Langidrik, Justina; Aitaoto, Nia

    2013-05-01

    Non-communicable diseases (NCD) have been identified as a health emergency in the US-associated Pacific Islands (USAPI).1 This assessment, funded by the National Institutes of Health, was conducted in the Republic of the Marshall Islands, Majuro Atoll and describes the burdens due to selected NCD (diabetes, heart disease, hypertension, stroke, chronic kidney disease); and assesses the system of service capacity and current activities for service delivery, data collection and reporting as well as identifying the issues that need to be addressed. Findings reveal that the risk factors of poor diet, lack of physical activity, and risky lifestyle behaviors are associated with overweight and obesity and subsequent NCD that are significant factors in the morbidity and mortality of the population. The leading causes of death include sepsis, cancer, diabetes-related deaths, pneumonia, and hypertension. Population-based survey for the RMI show that 62.5% of the adults are overweight or obese and the prevalence of diabetes stands at 19.6%. Other findings show significant gaps in the system of administrative, clinical, data, and support services to address these NCD. There is no policy and procedure manual for the hospital or public health diabetes clinics and there is little communication, coordination, or collaboration between the medical and public health staff. There is no functional data system that allows for the identification, registry, or tracking of patients with diabetes or other NCDs. Based on these findings, priority issues and problems to be addressed for the administrative, clinical, and data systems were identified.

  2. Bikini Atoll Rehabilitation Committee Report no. 5 Status March 31, 1987. Submitted to the U.S. Congress, House and Senate Committees on Interior Appropriations, pursuant to House Report 99-1002 and Public Law 99-500. Department of Interior Account no. 14X0414/TT-1580X08, Washington, DC

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-07-01

    The principal findings of Report No. 5, Bikini Atoll Rehabilitation Committee, March 31, 1987, are as follows: (1) Three principal methods for contamination control are under study at Bikini Atoll: removal of top soil, treatment of soil with potassium salt, and treatment by irrigation with sea water. The latter two should be cheaper and ecologically superior to excavation. All three methods have reduced the uptake of cesium-137 by coconuts and vegetables. (2) It is encouraging to report that in one sea water trial the beneficial effect has lasted for at least 1.6 years after treatment. Third-year results from the experiment should become available this year. (3) Various trials are under way to determine optimum treatment schedules (amount of agent per treatment, frequency of treatments) and the duration of the effects thereby engendered. Some schedules include more than one type of treatment. Initial results from these trials are becoming available during the present year. Until such detailed information is available and securely established, specific recommendations for a rehabilitation program should not be made. (4) It is now thought that the active agent in sea water is the sodium ion. Cation equivalency tests which take into account potassium, sodium and magnesium are under way. (5) As reported previously, Eneu may be settled now. BARC recommends that after Governmental review and possible modification, the conceptual designs now available be developed for engineering purposes to permit rehabilitation logistics and construction to get under way. (6) On the basis of the findings thus far, and making 'reasonable' assumptions about the construction costs of community facilities, BARC estimates that the total rehabilitation costs will lie in the range of $55 to $90 million. Most of the range is due to uncertainty regarding the decontamination program. (author)

  3. Bikini Atoll Rehabilitation Committee Report no. 5 Status March 31, 1987. Submitted to the U.S. Congress, House and Senate Committees on Interior Appropriations, pursuant to House Report 99-1002 and Public Law 99-500. Department of Interior Account no. 14X0414/TT-1580X08, Washington, DC

    International Nuclear Information System (INIS)

    1987-01-01

    The principal findings of Report No. 5, Bikini Atoll Rehabilitation Committee, March 31, 1987, are as follows: (1) Three principal methods for contamination control are under study at Bikini Atoll: removal of top soil, treatment of soil with potassium salt, and treatment by irrigation with sea water. The latter two should be cheaper and ecologically superior to excavation. All three methods have reduced the uptake of cesium-137 by coconuts and vegetables. (2) It is encouraging to report that in one sea water trial the beneficial effect has lasted for at least 1.6 years after treatment. Third-year results from the experiment should become available this year. (3) Various trials are under way to determine optimum treatment schedules (amount of agent per treatment, frequency of treatments) and the duration of the effects thereby engendered. Some schedules include more than one type of treatment. Initial results from these trials are becoming available during the present year. Until such detailed information is available and securely established, specific recommendations for a rehabilitation program should not be made. (4) It is now thought that the active agent in sea water is the sodium ion. Cation equivalency tests which take into account potassium, sodium and magnesium are under way. (5) As reported previously, Eneu may be settled now. BARC recommends that after Governmental review and possible modification, the conceptual designs now available be developed for engineering purposes to permit rehabilitation logistics and construction to get under way. (6) On the basis of the findings thus far, and making 'reasonable' assumptions about the construction costs of community facilities, BARC estimates that the total rehabilitation costs will lie in the range of $55 to $90 million. Most of the range is due to uncertainty regarding the decontamination program. (author)

  4. Rehabilitation costs

    Energy Technology Data Exchange (ETDEWEB)

    Kubo, Arthur S [BDM Corp., VA (United States); [Bikini Atoll Rehabilitation Committee, Berkeley, CA (United States)

    1986-07-01

    The costs of radioactivity contamination control and other matters relating to the resettlement of Bikin atoll were reviewed for Bikini Atoll Rehabilitation Committee by a panel of engineers which met in Berkeley, California on January 22-24, 1986. This Appendix presents the cost estimates.

  5. Rehabilitation costs

    International Nuclear Information System (INIS)

    Kubo, Arthur S.

    1986-01-01

    The costs of radioactivity contamination control and other matters relating to the resettlement of Bikin atoll were reviewed for Bikini Atoll Rehabilitation Committee by a panel of engineers which met in Berkeley, California on January 22-24, 1986. This Appendix presents the cost estimates

  6. Carbon budget of coral reef systems: an overview of observations in fringing reefs, barrier reefs and atolls in the Indo-Pacific regions

    International Nuclear Information System (INIS)

    Suzuki, Atsushi; Kawahata, Hodaka

    2003-01-01

    The seawater CO 2 system and carbon budget were examined in coral reefs of wide variety with respect to topographic types and oceanographic settings in the Indo-Pacific oceans. A system-level net organic-to-inorganic carbon production ratio (ROI) is a master parameter for controlling the carbon cycle in coral reef systems, including their sink/source behavior for atmospheric CO 2 . A reef system with ROI less than approximately 0.6 has a potential for releasing CO 2 . The production ratio, however, is not easy to estimate on a particular reef. Instead, observations planned to detect the offshore-lagoon difference in partial pressure of CO 2 (pCO 2 ) and a graphic approach based on a total alkalinity-dissolved inorganic carbon diagram can reveal system-level performance of the carbon cycle in coral reefs. Surface pCO 2 values in the lagoons of atolls and barrier reefs were consistently higher than those in their offshore waters, showing differences between 6 and 46 atm, together with a depletion in total alkalinity up to 100 mol/kg, indicating predominant carbonate production relative to net organic carbon production. Reef topography, especially residence time of lagoon water, has a secondary effect on the magnitude of the offshore-lagoon pCO 2 difference. Terrestrial influence was recognized in coastal reefs, including the GBR lagoon and a fringing reef of the Ryukyu Islands. High carbon input appears to enhance CO 2 efflux to the atmosphere because of their high dissolved C:P ratios. Coral reefs, in general, act as an alkalinity sink and a potentially CO 2 -releasing site due to carbonate precipitation and land-derived carbon

  7. Radiation doses and cancer risks in the Marshall Islands associated with exposure to radioactive fallout from Bikini and Enewetak nuclear weapons tests: summary.

    Science.gov (United States)

    Simon, Steven L; Bouville, André; Land, Charles E; Beck, Harold L

    2010-08-01

    Nuclear weapons testing conducted at Bikini and Enewetak Atolls during 1946-1958 resulted in exposures of the resident population of the present-day Republic of the Marshall Islands to radioactive fallout. This paper summarizes the results of a thorough and systematic reconstruction of radiation doses to that population, by year, age at exposure, and atoll of residence, and the related cancer risks. Detailed methods and results are presented in a series of companion papers in this volume. From our analysis, we concluded that 20 of the 66 nuclear tests conducted in or near the Marshall Islands resulted in measurable fallout deposition on one or more of the inhabited atolls of the Marshall Islands. In this work, we estimated deposition densities (kBq m(-2)) of all important dose-contributing radionuclides at each of the 32 atolls and separate reef islands of the Marshall Islands. Quantitative deposition estimates were made for 63 radionuclides from each test at each atoll. Those estimates along with reported measurements of exposure rates at various times after fallout were used to estimate radiation absorbed doses to the red bone marrow, thyroid gland, stomach wall, and colon wall of atoll residents from both external and internal exposure. Annual doses were estimated for six age groups ranging from newborns to adults. We found that the total deposition of 137Cs, external dose, internal organ doses, and cancer risks followed the same geographic pattern with the large population of the southern atolls receiving the lowest doses. Permanent residents of the southern atolls who were of adult age at the beginning of the testing period received external doses ranging from 5 to 12 mGy on average; the external doses to adults at the mid-latitude atolls ranged from 22 to 59 mGy on average, while the residents of the northern atolls received external doses in the hundreds to over 1,000 mGy. Internal doses varied significantly by age at exposure, location, and organ. Except

  8. Northern Marshall Islands radiological survey: sampling and analysis summary

    Energy Technology Data Exchange (ETDEWEB)

    Robison, W.L.; Conrado, C.L.; Eagle, R.J.; Stuart, M.L.

    1981-07-23

    A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for /sup 241/Am, 6569 for /sup 137/Cs, 4535 for /sup 239 +240/Pu, 4431 for /sup 90/Sr, 1146 for /sup 238/Pu, 269 for /sup 241/Pu, and 114 each for /sup 239/Pu and /sup 240/Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included.

  9. Northern Marshall Islands radiological survey: sampling and analysis summary

    International Nuclear Information System (INIS)

    Robison, W.L.; Conrado, C.L.; Eagle, R.J.; Stuart, M.L.

    1981-01-01

    A radiological survey was conducted in the Northern Marshall Islands to document reamining external gamma exposures from nuclear tests conducted at Enewetak and Bikini Atolls. An additional program was later included to obtain terrestrial and marine samples for radiological dose assessment for current or potential atoll inhabitants. This report is the first of a series summarizing the results from the terrestrial and marine surveys. The sample collection and processing procedures and the general survey methodology are discussed; a summary of the collected samples and radionuclide analyses is presented. Over 5400 samples were collected from the 12 atolls and 2 islands and prepared for analysis including 3093 soil, 961 vegetation, 153 animal, 965 fish composite samples (average of 30 fish per sample), 101 clam, 50 lagoon water, 15 cistern water, 17 groundwater, and 85 lagoon sediment samples. A complete breakdown by sample type, atoll, and island is given here. The total number of analyses by radionuclide are 8840 for 241 Am, 6569 for 137 Cs, 4535 for 239+240 Pu, 4431 for 90 Sr, 1146 for 238 Pu, 269 for 241 Pu, and 114 each for 239 Pu and 240 Pu. A complete breakdown by sample category, atoll or island, and radionuclide is also included

  10. The Ecology of Coral Reef Top Predators in the Papahānaumokuākea Marine National Monument

    Directory of Open Access Journals (Sweden)

    Jonathan J. Dale

    2011-01-01

    Full Text Available Coral reef habitats in the Papahānaumokuākea Marine National Monument (PMNM are characterized by abundant top-level predators such as sharks and jacks. The predator assemblage is dominated both numerically and in biomass by giant trevally (Caranx ignobilis and Galapagos sharks (Carcharhinus galapagensis. A lower diversity of predatory teleosts, particularly groupers and snappers, distinguishes the PMNM from other remote, unfished atolls in the Pacific. Most coral reef top predators are site attached to a “home” atoll, but move extensively within these atolls. Abundances of the most common sharks and jacks are highest in atoll fore reef habitats. Top predators within the PMNM forage on a diverse range of prey and exert top-down control over shallow-water reef fish assemblages. Ecological models suggest ecosystem processes may be most impacted by top predators through indirect effects of predation. Knowledge gaps are identified to guide future studies of top predators in the PMNM.

  11. Comparison of radionuclide concentrations in 1956 and 1973 Enewetak beach material

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, N.; Rahon, T.E.; Hirshfield, H.

    1985-02-01

    During the period 1948-1958, approximately 40 nuclear weapons tests were performed on the Enewetak Atoll in the Marshall Islands of the central Pacific Ocean. In 1973, the results of a survey contracted by the US Atomic Energy Commission specified that extensive decontamination of the land areas would be necessary before the people of Enewetak could return to the atoll. During Operation Redwing in 1956, several members of the New York University Departments of Biology and Environmental Medicine visited the atoll and collected water, plankton and beach coral samples to study the distribution of foraminifera among the islands of Enewetak and other nearby atolls. Of the specimens collected, 22 samples of beach material from the highly contaminated northern islands of Enewetak remained intact and were available for study. Analyses of the radionuclide concentrations of these samples have provided interesting information regarding the levels of contamination that existed on Enewetak at that time.

  12. 2014/2015 Investigations of the Ontong Java and Kerguelen Plateaus

    Science.gov (United States)

    Coffin, M. F.; Whittaker, J. M.

    2013-12-01

    The two largest oceanic plateaus, Ontong Java in the western Pacific, and Kerguelen in the southern Indian Ocean, will be the focus of scheduled multidisciplinary/interdisciplinary shipboard expeditions in 2014 and 2015. In mid-2014, scientists aboard the Schmidt Ocean Institute's RV Falkor will investigate the origin and evolution of two large atolls, Ontong Java and Nukumanu, surmounting the ca 122 Ma Ontong Java Plateau, as well how Kroenke Canyon, which deeply incises the plateau, formed and evolved. First-ever multibeam bathymetry and sub-bottom profiling data from the atolls and canyon will reveal their submarine and shallow sub-seafloor morphology, and, if combined with geochemical and geochronological analyses of potential igneous basement samples, will yield important information on their origin and evolution. The primary goals of this atoll and canyon project are: to test potential genetic relationships between a) the atolls and the OJP, and b) the atolls and Kroenke Canyon; to understand and model how atolls and canyons form and evolve on oceanic plateaus, isolated from terrestrial influences and subject to sea level fluctuations; and to contribute to understanding tsunami risk on low-lying atolls. In late 2014 and early 2015, researchers aboard Australia's new Marine National Facility, RV Investigator, will investigate active submarine hotspot volcanism on the Kerguelen Plateau and its consequences. The project's overall aim is to test the hypothesis that hydrothermal activity driven by active submarine magmatism fertilizes surface waters with iron that enhances primary biological productivity. Surmounting the Cretaceous plateau, Heard and McDonald Islands are among the world's most active hotspot volcanoes, and new multibeam bathymetry and sub-bottom profiling data will enable identification of candidate active submarine volcanoes, which we will sample. In the overlying water column, we will collect samples to test for the presence or absence of

  13. Polydactyly in the central pacific gecko, Lepidodactylus sp. (Squamata: Gekkonidae)

    Science.gov (United States)

    Bauer, A.M.; Hathaway, S.A.; Fisher, R.N.

    2009-01-01

    We report the first known case of naturally occurring polydactyly in a gekkotan lizard. A single individual from Palmyra Atoll exhibited a triplication of digit III of the m hand. No obvious teratogenic sources are present on the atoll and the causal factors of polydactyly in Lepidodactylus sp. remain unknown.

  14. 32 CFR 761.5 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... measured from the low water line of any island, islet, atoll, reef, or rocks within the jurisdiction of the... purpose of this definition, the term “coast” includes the coasts of islands, islets, rocks, atolls, reefs... Defense Department of Defense (Continued) DEPARTMENT OF THE NAVY ISLANDS UNDER NAVY JURISDICTION NAVAL...

  15. Carbon budget of coral reef systems: an overview of observations in fringing reefs, barrier reefs and atolls in the Indo-Pacific regions

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Atsushi; Kawahata, Hodaka [National Inst. of Advanced Industrial Science and Technology, Ibaraki (Japan). Inst. for Marine Resources and Environment

    2003-04-01

    The seawater CO{sub 2} system and carbon budget were examined in coral reefs of wide variety with respect to topographic types and oceanographic settings in the Indo-Pacific oceans. A system-level net organic-to-inorganic carbon production ratio (ROI) is a master parameter for controlling the carbon cycle in coral reef systems, including their sink/source behavior for atmospheric CO{sub 2}. A reef system with ROI less than approximately 0.6 has a potential for releasing CO{sub 2}. The production ratio, however, is not easy to estimate on a particular reef. Instead, observations planned to detect the offshore-lagoon difference in partial pressure of CO{sub 2} (pCO{sub 2}) and a graphic approach based on a total alkalinity-dissolved inorganic carbon diagram can reveal system-level performance of the carbon cycle in coral reefs. Surface pCO{sub 2} values in the lagoons of atolls and barrier reefs were consistently higher than those in their offshore waters, showing differences between 6 and 46 atm, together with a depletion in total alkalinity up to 100 mol/kg, indicating predominant carbonate production relative to net organic carbon production. Reef topography, especially residence time of lagoon water, has a secondary effect on the magnitude of the offshore-lagoon pCO{sub 2} difference. Terrestrial influence was recognized in coastal reefs, including the GBR lagoon and a fringing reef of the Ryukyu Islands. High carbon input appears to enhance CO{sub 2} efflux to the atmosphere because of their high dissolved C:P ratios. Coral reefs, in general, act as an alkalinity sink and a potentially CO{sub 2}-releasing site due to carbonate precipitation and land-derived carbon.

  16. [Decompression sickness accident management in remote areas. Use of immediate in-water recompression therapy. Review and elaboration of a new protocol targeted for a mission at Clipperton atoll].

    Science.gov (United States)

    Blatteau, J-E; Jean, F; Pontier, J-M; Blanche, E; Bompar, J-M; Meaudre, E; Etienne, J-L

    2006-08-01

    In-Water Recompression (IWR) is defined as a treatment of decompression sickness by immediate underwater recompression after the onset of symptoms in remote areas where hyperbaric chambers are not available. At least three methods of IWR have been published. They used pure oxygen breathing for prolonged periods of time at a depth of 9 m. IWR effectiveness in comparison with standard recompression techniques has not been assessed. IWR should be used in remote localities as an immediate measure to stop the evolution of decompression illness before evacuating the victim for subsequent treatment to the nearest hyperbaric facility. Resulting from environmental conditions, the risks of drowning and hypothermia are the most often quoted, pure oxygen breathing at 9 m can also expose to acute oxygen toxicity. The objectives of this work are: first, to examine existing published methods of IWR; second, to propose a new method of IWR. All published methods of IWR involve victim returning underwater for a long period of time. But dehydration due to a long period of immersion can worsen symptoms of decompression illness and acute oxygen toxicity is also related to the duration of the exposition. In response to these considerations we developed a shorter method of conducting IWR specifically targeted for a diving mission at Clipperton atoll in the Northern Pacific Ocean.

  17. Time-resolved record of 236U and 239,240Pu isotopes from a coral growing during the nuclear testing program at Enewetak Atoll (Marshall Islands).

    Science.gov (United States)

    Froehlich, M B; Chan, W Y; Tims, S G; Fallon, S J; Fifield, L K

    2016-12-01

    A comprehensive series of nuclear tests were carried out by the United States at Enewetak Atoll in the Marshall Islands, especially between 1952 and 1958. A Porites Lutea coral that was growing in the Enewetak lagoon within a few km of all of the high-yield tests contains a continuous record of isotopes, which are of interest (e.g. 14 C, 236 U, 239,240 Pu) through the testing period. Prior to the present work, 14 C measurements at ∼2-month resolution had shown pronounced peaks in the Δ 14 C data that coincided with the times at which tests were conducted. Here we report measurements of 236 U and 239,240 Pu on the same coral using accelerator mass spectrometry, and again find prominent peaks in the concentrations of these isotopes that closely follow those in 14 C. Consistent with the 14 C data, the magnitudes of these peaks do not, however, correlate well with the explosive yields of the corresponding tests, indicating that smaller tests probably contributed disproportionately to the debris that fell in the lagoon. Additional information about the different tests can also be obtained from the 236 U/ 239 Pu and 240 Pu/ 239 Pu ratios, which are found to vary dramatically over the testing period. In particular, the first thermonuclear test, Ivy-Mike, has characteristic 236 U/ 239 Pu and 240 Pu/ 239 Pu signatures which are diagnostic of the first arrival of nuclear test material in various archives. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Multi-decadal shoreline changes on Takú Atoll, Papua New Guinea: Observational evidence of early reef island recovery after the impact of storm waves

    Science.gov (United States)

    Mann, Thomas; Westphal, Hildegard

    2016-03-01

    Hurricanes, tropical cyclones and other high-magnitude events are important steering mechanisms in the geomorphic development of coral reef islands. Sandy reef islands located outside the storm belts are strongly sensitive to the impact of occasional high-magnitude events and show abrupt, commonly erosive geomorphic change in response to such events. Based on the interpretation of remote sensing data, it is well known that the process of landform recovery might take several decades or even longer. However, despite the increasing amount of scientific attention towards short- and long-term island dynamics, the lack of data and models often prevent a robust analysis of the timing and nature of recovery initiation. Here we show how natural island recovery starts immediately after the impact of a high-magnitude event. We analyze multi-temporal shoreline changes on Takú Atoll, Papua New Guinea and combine our findings with a unique set of published field observations (Smithers and Hoeke, 2014). Trends of shoreline change since 1943 and changes in planform island area indicate a long-term accretionary mode for most islands. Apparent shoreline instability is detected for the last decade of analysis, however this can be explained by the impact of storm waves in December 2008 that (temporarily?) masked the long-term trend. The transition from negative to positive rates of change in the aftermath of this storm event is indicative of inherent negative feedback processes that counteract short-term changes in energy input and represent the initiation of island recovery. Collectively, our results support the concept of dynamic rather than static reef islands and clearly demonstrate how short-term processes can influence interpretations of medium-term change.

  19. Bibliographic checklist of the marine benthic algae of Central Polynesia in the Pacific Ocean (Excluding Hawai‘i and French Polynesia

    Directory of Open Access Journals (Sweden)

    Tsuda, R.T.

    2013-04-01

    Full Text Available The Polynesian algal bibliographic checklist is based on records from past references for American Samoa and Samoa (380 spp., Cook Islands (111 spp., Johnston Atoll (190 spp., Line Islands (250 spp., Niue (3 spp., Phoenix Islands (193 spp., Pitcairn Islands (23 spp., Tokelau (1 sp., Tonga (109 spp., Wake Atoll (121 spp. and Wallis and Futuna (191 spp. and consists of three sections. The first section (I. Classification provides a listing of classes, orders, and families of the 238 genera of Polynesian algae. The second section (II. Species-Reference Index provides an alphabetized listing of the 667 named algal species under the four Phyla, i.e., Cyanobacteria (68 species, Rhodophyta (373 species, Ochrophyta (59 species and Chlorophyta (167 species with the applicable reference citations for each island or atoll. Brief taxonomic or nomenclatural notes are provided, when appropriate, for selected species. The third section (III. Island-Reference Index provides a chronological listing of all published references for the respective island or atoll in each island group. The complete references for all citations in the text are provided in the Reference section.

  20. Water supply

    International Nuclear Information System (INIS)

    Peterson, F.L.

    1986-01-01

    Options and methodologies for the development of fresh water supplies on Bikini Atoll are much the same as those practiced in the rest of the Marshall Islands and for that matter, most atolls in the central Pacific Ocean Basin. That is, rainfall distribution on Bikini produces a distinct wet season, lasting from about May through November, with the remaining months being generally dry. As a result, fresh water from surface catchments tends to be plentiful during the wet season? but is usually scarce during the dry months, and alternative sources such as groundwater must be utilized during this time. On Bikini the problems of fresh water supply are somewhat more difficult than for most Marshall Island atolls because rainfall is only about half the Marshall Island's average. Tus water supply is a critical factor limiting the carrying capacity of Bikini Atoll. To address this problem BARC has undertaken a study of the Bikini Atoll water supply. Te primary objectives of this work are to determine: (1) alternatives available for fresh water supply, 2 the amounts, location and quality of available supplies and 3 optimal development methods. The study planned for one's year duration, has been underway only since the summer of 1985 and is thus not yet fully completed. However, work done to date, which is presented in this report of preliminary findings, provides a reasonably accurate picture of Bikini's fresh water supplies and the various options available for their development. The work remaining to be completed will mainly add refinements to the water supply picture presented in the sections to follow

  1. Radiological assessments for resettlement of Rongelap in the Republic of the Marshall Islands

    International Nuclear Information System (INIS)

    1994-01-01

    The Committee on Radiological Safety in the Marshall Islands was established by the National Research Council in response to a request from the US Department of Energy (DOE) to assist the department in evaluating radiological conditions on certain atolls in the Republic of the Marshall Islands, especially Rongelap Atoll. The need stems from the provisions of a memorandum of understanding (MOU) established between the Republic of the Marshall Islands and the US in 1992. That agreement sets out criteria and stipulations pertaining to the resettlement of Rongelap Atoll. The issue of resettlement itself originated in the desire for the people of the Marshall Islands to return to the atolls from which they were evacuated as a consequence of nuclear-weapons testing by the US during the 1940s and 1950s. The National Research Council was asked to review the scientific studies undertaken by the US Department of Energy to determine if reliable and modern scientific methodology was being used to assess the potential hazard, if any, to persons who might return to live on Rongelap Atoll. A crucial provision of the MOU is that resettlement will occur only if no person returning to Rongelap and substituting on a native-foods-only diet will receive a calculated annual whole-body radiation dose equivalent of more than 100 mrem above background. The MOU also presents an action level of 17 pCi/g for the concentration of transuranic contamination, i.e., plutonium and americium, in soils below which mitigation will be considered unnecessary

  2. Radiological Situation at the Bomb Test Sites

    International Nuclear Information System (INIS)

    Valkovic, V.

    1998-01-01

    An overview of radiological situation at the selected bomb test sites is presented. The report is based on the reports and measurements performed by IAEA while the author was a head of its Physics-Chemistry-Instrumentation Laboratory. Radiological conditions at Bikini Atoll (USA testing ground), Mururoa and Fangataufa Atolls (French testing ground) and Semipalatinsk (SSSR testing ground) have been discussed in some details. (author)

  3. Hierarchical drivers of reef-fish metacommunity structure.

    Science.gov (United States)

    MacNeil, M Aaron; Graham, Nicholas A J; Polunin, Nicholas V C; Kulbicki, Michel; Galzin, René; Harmelin-Vivien, Mireille; Rushton, Steven P

    2009-01-01

    Coral reefs are highly complex ecological systems, where multiple processes interact across scales in space and time to create assemblages of exceptionally high biodiversity. Despite the increasing frequency of hierarchically structured sampling programs used in coral-reef science, little progress has been made in quantifying the relative importance of processes operating across multiple scales. The vast majority of reef studies are conducted, or at least analyzed, at a single spatial scale, ignoring the implicitly hierarchical structure of the overall system in favor of small-scale experiments or large-scale observations. Here we demonstrate how alpha (mean local number of species), beta diversity (degree of species dissimilarity among local sites), and gamma diversity (overall species richness) vary with spatial scale, and using a hierarchical, information-theoretic approach, we evaluate the relative importance of site-, reef-, and atoll-level processes driving the fish metacommunity structure among 10 atolls in French Polynesia. Process-based models, representing well-established hypotheses about drivers of reef-fish community structure, were assembled into a candidate set of 12 hierarchical linear models. Variation in fish abundance, biomass, and species richness were unevenly distributed among transect, reef, and atoll levels, establishing the relative contribution of variation at these spatial scales to the structure of the metacommunity. Reef-fish biomass, species richness, and the abundance of most functional-groups corresponded primarily with transect-level habitat diversity and atoll-lagoon size, whereas detritivore and grazer abundances were largely correlated with potential covariates of larval dispersal. Our findings show that (1) within-transect and among-atoll factors primarily drive the relationship between alpha and gamma diversity in this reef-fish metacommunity; (2) habitat is the primary correlate with reef-fish metacommunity structure at

  4. Chromosome aberrations in Japanese fishermen exposed to fallout radiation 420-1200 km distant from the nuclear explosion test site at Bikini Atoll: report 60 years after the incident

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Kimio [Hiroshima University, Research Institute for Radiation Biology and Medicine, Hiroshima City, Hiroshima (Japan); Institute for Environmental Sciences, Kakimita, Aomori (Japan); Ohtaki, Megu; Hoshi, Masaharu [Hiroshima University, Research Institute for Radiation Biology and Medicine, Hiroshima City, Hiroshima (Japan)

    2016-08-15

    During the period from March to May, 1954, the USA conducted six nuclear weapon tests at the ''Bravo'' detonation sites at the Bikini and Enewetak Atolls, Marshall Islands. At that time, the crew of tuna fishing boats and cargo ships that were operating approximately 150-1200 km away from the test sites were exposed to radioactive fallout. The crew of the fishing boats and those on cargo ships except the ''5th Fukuryu-maru'' did not undergo any health examinations at the time of the incident. In the present study, chromosome aberrations in peripheral blood lymphocytes were examined in detail by the G-banding method in 17 crew members from 8 fishing boats and 2 from one cargo ship, 60 years after the tests. None of the subjects examined had suffered from cancer. The percentages of both stable-type aberrations such as translocation, inversion and deletion, and unstable-type aberrations such as dicentric and centric ring in the study group were significantly higher (1.4- and 2.3-fold, respectively) than those in nine age-matched controls. In the exposed and control groups, the percentages of stable-type aberrations were 3.35 % and 2.45 %, respectively, and the numbers of dicentric and centric ring chromosomes per 100 cells were 0.35 and 0.15, respectively. Small clones were observed in three members of the exposed group. These results suggest that the crews were exposed to slightly higher levels of fallout than had hitherto been assumed. (orig.)

  5. Urinary excretion of radionuclides from Marshallese exposed to fallout from the 1954 Bravo nuclear test.

    Science.gov (United States)

    Harris, Payne S; Simon, Steven L; Ibrahim, Shawki A

    2010-08-01

    Soon after the Bravo nuclear test at Bikini Atoll in the Marshall Islands on 1 March 1954, urine samples were collected for analysis of excreted radioactivity from native residents exposed to radioactive fallout on two atolls as well as from U.S. military personnel on a third atoll. The earliest acquired samples, obtained by the Los Alamos Scientific Laboratory (LASL), were assayed for various radionuclides and provided the first known measurements of (131)I in urine following exposure to fallout from a nuclear test. Over the course of 1954, many additional samples were collected by the LASL, as well as by the Atomic Energy Commission New York Operations Office's Health and Safety Laboratory and the Naval Radiological Defense Laboratory. Collectively, the groups sampled included Marshallese exposed on Rongelap and Ailinginae Atolls, American military weather observers temporarily resident on Rongerik Atoll, and sailors from the Japanese fishing vessel, the Lucky Dragon. While the bioassay measurement data and individual urine volumes have been crucial to various attempts to assess intakes of radioactivity and the related internal radiation doses among the Marshallese, those data have never been published in any peer-reviewed journal, but have been restricted to agency memoranda, laboratory reports, and summaries in some publications and book chapters. Reconstructions of internal doses to Marshallese in 1954 and in later years have depended on these data and, hence, they have considerable historical importance as well as importance to ongoing health risk projections for Marshallese. This paper presents much of the original data on urine volumes and radioactivity from the various assays of urine for radionuclides, and compares estimates of (131)I intakes made in 1954, 1985, 1987, and 2008.

  6. Radionuclide concentrations and dose assessment of cistern water and groundwater at the Marshall Islands

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.; Robison, W.L.

    1981-01-01

    A radiological survey was conducted from September through November of 1978 to determine the concentrations of radionuclides in the terrestrial and marine environments of 11 atolls and 2 islands in the Northern Marshall Islands. More than 70 cistern and groundwater samples were collected at the atolls; the volume of each sample was between 55 and 100 l. The concentration of 90 Sr in cistern water at most atolls is that expected from world-wide fallout in wet deposition. Except for Bikini and Rongelap, 137 Cs concentrations in cistern water are in agreement with the average predicted concentrations from wet deposition. The 239+240 Pu concentrations are everywhere less than the predicted fallout concentrations except at Rongelap, Ailinginae, and Bikini where the measured and predicted concentrations are in general agreement. During the period sampled, most groundwater concentrations of 90 Sr and 137 Cs were everywhere higher than the concentrations in cistern water. Concentrations of the transurancies in filtered groundwater solution were everywhere comparable to or less than the concentrations in cistern water. It is concluded that the concentrations of radionuclides detected during any single period may not necessarily reflect the long-term average concentrations or the concentrations that might be observed if a lined well were extended above the surface. In any case, at all atolls the 90 Sr and 137 Cs concentrations in groundwater are below the concentration guidelines for drinking water recommended by the Environmental Protection Agency. The maximum annual dose rates and the 30- and 50-y integral doses are calculated for the intake of both cistern water and groundwater for each of the atolls

  7. Comparative concentrations of 137Cs, 90Sr, /sup 239,240/Pu, and 241Am in tissues of fish from the Marshall Islands and calculated dose commitments from their consumption

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Robison, W.L.

    1987-01-01

    Body burdens of 90 Sr, 137 Cs, and the transuranics in bottom-feeding fish from Marshall Island atolls are derived, in part, from the quantities of the radionuclides irreversibly fixed to ingested carbonate material. Radionuclide concentration factors for different species of fish are characterized by relating tissue concentrations to those in filtered seawater. For bottom-feeding fish, the values are lower at the lesser contaminated atolls than those values determined for the same species at the more contaminated atolls. These fish have the ability to lower their gut pH during feeding. When this occurs, there is a dissolution of a fraction of the ingested calcium carbonate containing radionuclides that were fixed or fused internally to the material during nuclear testing. Fractions of the radionuclides released during solution in carbonate matrix are available for passage across the gut wall. Amounts released to solution in the gut are proportional to the levels of contamination at the different atolls. Concentration factors for higher trophic level species, which do not rely on sediments or coral for their source of food, show no such trends between differentially contaminated atolls. A two-source model used to compute the internal concentrations is described. Americium-241 seems to be more biologically available than /sup 239,240/Pu to higher trophic level species from the lagoons, whereas at lower trophic levels the opposite seems to be the case. Cesium-137 is now the largest contributor of the small radiological dose to man from the marine fish pathway, with the transuranics contributing from 2 to 30% of the total dose. 22 references, 1 figure, 19 tables

  8. What are become Moruroa and Fangataufa? The dismantling of tests sites did not happen; Que sont devenus Moruroa et Fangataufa? le demantelement des sites d'essais n'a pas eu lieu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Officially, the nuclear test sites of French polynesia have been dismantled. It would be more correct to say that the installations build on the Moruroa atolls have been destroyed. From the end of nuclear tests, the Cea constructions and installations, the most susceptible to be contaminated have been ruined without exterior witness. Nobody knows if the usual procedures of decontamination have been observed. About 15% of materials from he Moruroa base have been distributed as gifts to the local communities in french Polynesia. other materials have been transferred or sold. The observatory of French nuclear weapons estimates the cost of the closing of the French Polynesia test sites to about 15 milliards of Francs, including the compensations paid to the Polynesian government during 10 yeas, so be it hundred times the cost announced by the militaries in 1998. The observatory of French nuclear weapons estimates that the real assessment of radioactive waste being on Moruroa and Fangataufa atolls has not been completely made by the experts of IAEA. This assessment is still to make. The observatory of French nuclear weapons notices that the Moruroa and Fangataufa atolls stay under military status. It recommends that these atolls be reintegrated to the Polynesian land patrimony in order to allow independent expertise. (N.C.)

  9. Transuranic concentrations in reef and pelagic fish from the Marshall Islands

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.

    1980-09-01

    Concentrations of /sup 239 + 240/Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of /sup 239 + 240/Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analyzed. A progressive discrimination against /sup 239 + 240/Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for /sup 239 + 240/Pu among all fish, which include bottom feeding and grazing herbivores, bottom feeding carnivores, and pelagic carnivores from different atoll locations. The average concentration of /sup 239 + 240/Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other, lesser contaminated atolls. Concentrations among all 3rd, 4th, and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known

  10. What are become Moruroa and Fangataufa? The dismantling of tests sites did not happen

    International Nuclear Information System (INIS)

    2005-01-01

    Officially, the nuclear test sites of French polynesia have been dismantled. It would be more correct to say that the installations build on the Moruroa atolls have been destroyed. From the end of nuclear tests, the Cea constructions and installations, the most susceptible to be contaminated have been ruined without exterior witness. Nobody knows if the usual procedures of decontamination have been observed. About 15% of materials from he Moruroa base have been distributed as gifts to the local communities in french Polynesia. other materials have been transferred or sold. The observatory of French nuclear weapons estimates the cost of the closing of the French Polynesia test sites to about 15 milliards of Francs, including the compensations paid to the Polynesian government during 10 yeas, so be it hundred times the cost announced by the militaries in 1998. The observatory of French nuclear weapons estimates that the real assessment of radioactive waste being on Moruroa and Fangataufa atolls has not been completely made by the experts of IAEA. This assessment is still to make. The observatory of French nuclear weapons notices that the Moruroa and Fangataufa atolls stay under military status. It recommends that these atolls be reintegrated to the Polynesian land patrimony in order to allow independent expertise. (N.C.)

  11. What are become Moruroa and Fangataufa? The dismantling of tests sites did not happen; Que sont devenus Moruroa et Fangataufa? le demantelement des sites d'essais n'a pas eu lieu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Officially, the nuclear test sites of French polynesia have been dismantled. It would be more correct to say that the installations build on the Moruroa atolls have been destroyed. From the end of nuclear tests, the Cea constructions and installations, the most susceptible to be contaminated have been ruined without exterior witness. Nobody knows if the usual procedures of decontamination have been observed. About 15% of materials from he Moruroa base have been distributed as gifts to the local communities in french Polynesia. other materials have been transferred or sold. The observatory of French nuclear weapons estimates the cost of the closing of the French Polynesia test sites to about 15 milliards of Francs, including the compensations paid to the Polynesian government during 10 yeas, so be it hundred times the cost announced by the militaries in 1998. The observatory of French nuclear weapons estimates that the real assessment of radioactive waste being on Moruroa and Fangataufa atolls has not been completely made by the experts of IAEA. This assessment is still to make. The observatory of French nuclear weapons notices that the Moruroa and Fangataufa atolls stay under military status. It recommends that these atolls be reintegrated to the Polynesian land patrimony in order to allow independent expertise. (N.C.)

  12. Transuranic concentrations in reef and pelagic fish from the Marshall Islands

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.

    1981-01-01

    Concentrations of sup(239+240)Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of sup(239+240)Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analysed. A progressive discrimination against sup(239+240)Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for sup(239+240)Pu among all fish, which include bottom-feeding and grazing herbivores, bottom-feeding carnivores and pelagic carnivores from different atoll locations. The average concentration of sup(239+240)Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other lesser contaminated atolls. Concentrations among all 3rd, 4th and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known. (author)

  13. Transuranic concentrations in reef and pelagic fish from the Marshall Islands. [/sup 239/Pu, /sup 240/Pu

    Energy Technology Data Exchange (ETDEWEB)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.

    1980-09-01

    Concentrations of /sup 239 + 240/Pu are reported in tissues of several species of reef and pelagic fish caught at 14 different atolls in the northern Marshall Islands. Several regularities that are species dependent are evident in the distribution of /sup 239 + 240/Pu among different body tissues. Concentrations in liver always exceeded those in bone and concentrations were lowest in the muscle of all fish analyzed. A progressive discrimination against /sup 239 + 240/Pu was observed at successive trophic levels at all atolls except Bikini and Enewetak, where it was difficult to conclude if any real difference exists between the average concentration factor for /sup 239 + 240/Pu among all fish, which include bottom feeding and grazing herbivores, bottom feeding carnivores, and pelagic carnivores from different atoll locations. The average concentration of /sup 239 + 240/Pu in the muscle of surgeonfish from Bikini and Enewetak was not significantly different from the average concentrations determined in these fish at the other, lesser contaminated atolls. Concentrations among all 3rd, 4th, and 5th trophic level species are highest at Bikini where higher environmental concentrations are found. The reasons for the anomalously low concentrations in herbivores from Bikini and Enewetak are not known.

  14. Measurement of background gamma radiation in the northern Marshall Islands

    OpenAIRE

    Bordner, Autumn S.; Crosswell, Danielle A.; Katz, Ainsley O.; Shah, Jill T.; Zhang, Catherine R.; Nikolic-Hughes, Ivana; Hughes, Emlyn W.; Ruderman, Malvin A.

    2016-01-01

    Sixty-seven nuclear tests were conducted on two atolls in the northern Marshall Islands between 1946 and 1958. These tests produced radioactive fallout, which even today gives rise to radiation measurable above naturally occurring background levels. Rather than obtain new data, recent estimates of contamination levels in the northern Marshall Islands use measurements made decades ago to calculate present radiation levels. In contrast, we report on timely measurements on three different atolls...

  15. Radiating paradise

    Energy Technology Data Exchange (ETDEWEB)

    Heuseler, H.

    1981-05-06

    Decades after the a-bomb experiments in the desert of Nevada, cases of illness occur more frequently: many former soldiers who had to observe the tests as spectators suffer from leukemia, skin and thyroid ulcers. Even worse are the late results of the nuclear weapon tests in the Pacific: on Bikini and Eniwetok, once paradise-like atolls, the death from radiation is waiting, an attempt to recultivate the bombed Bikini Atoll failed.

  16. Fallout Deposition in the Marshall Islands from Bikini and Enewetak Nuclear Weapons Tests

    OpenAIRE

    Beck, Harold L.; Bouville, André; Moroz, Brian E.; Simon, Steven L.

    2010-01-01

    Deposition densities (Bq m-2) of all important dose-contributing radionuclides occurring in nuclear weapons testing fallout from tests conducted at Bikini and Enewetak Atolls (1946-1958) have been estimated on a test-specific basis for all the 31 atolls and separate reef islands of the Marshall Islands. A complete review of various historical and contemporary data, as well as meteorological analysis, was used to make judgments regarding which tests deposited fallout in the Marshall Islands an...

  17. Christmas Island lagoonal lakes, models for the deposition of carbonate–evaporite–organic laminated sediments

    OpenAIRE

    Trichet , Jean; Défarge , Christian; Tribble , J.; Tribble , G.W.; Sansone , F.J.

    2001-01-01

    The atoll of Christmas Island (now known as Kiritimati) in the Kiribati Republic (Central Pacific) lies at about 2°N in the intertropical convergence zone. Much of the surface area of the atoll (ca. 360 km2) is occupied by numerous lakes in which carbonate, evaporite (calcium sulfate, halite) and organic layers are deposited. Observations suggest that deposition of these different laminae is controlled by climatic and biologic factors. It is thought that periodic climatic variations, such as ...

  18. Concentrations of radionuclides in reef and lagoon pelagic fish from the Marshall Islands

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Eagle, R.J.; Wong, K.M.; Jokela, T.A.; Brunk, J.L.; Marsh, K.V.

    1981-07-01

    A radiological survey was conducted from September through November of 1978 to assess the concentrations of persistent man-made radionuclides in the terrestrial and marine environments of 11 atolls and 2 islands of the Northern Marshall Islands. The atolls and islands include Rongelap, Utirik, Taka, Bikar, Rongerik, Ailinginae, Likiep, Jemo, Ailuk, Mejet, Wotho, Ujelang and Bikini. Over 4000 terrestrial and marine samples were collected for radionuclide analysis from 76 different islands. Soils, vegetation, indigenous animals, and cistern and groundwater were collected from the islands. Reef fish, pelagic species, clams, lagoon water, and sediments were obtained from the lagoons. A report is given of all available concentration data for 137 Cs, 90 Sr, /sup 239+240/Pu, 238 Pu, 241 Am as well as naturally occurring 40 K and other gamma emitting radionuclides in tissues and organs of different species of fish collected from the atolls

  19. Findings of the first comprehensive radiological monitoring program of the Republic of the Marshall Islands

    International Nuclear Information System (INIS)

    Simon, S.L.; Graham, J.C.

    1997-01-01

    The Marshall Islands was the primary site of the United States atomic weapons testing program in the Pacific. From 1946 through 1958, 66 atomic weapons were detonated in the island country. For several decades, monitoring was conducted by the U.S. Department of Energy (or its predecessor agencies) on the test site atolls and neighboring atolls. However, 70% of the land area of the over 1,200 islands in the Marshall Islands was never systematically monitored prior to 1990. For the 5-y period from 1990 through 1994, the Government of the Republic of the Marshall Islands undertook an independent program to assess the radiological conditions throughout its 29 atolls. The scientific work was performed under the auspices of the Section 177 Agreement of the Compact of Free Association, U.S. public law 99-239, signed in 1986 by President Ronald Reagan. Although the total land area of the nations is a scant 180 km 2 , the islands are distributed over 6 X 10 5 km 2 of ocean. Consequently, logistics and instrumentation were main considerations, in addition to cultural and language issues. The objective of this paper is to report findings for all atolls of the Marshall Islands on the 137 Cs areal inventory (Bq m -2 ) and the external effective dose-rate (mSv y -1 ), the projected internal effective dose-rate (mSv y -1 ) from an assumed diet model, and surface soil concentrations of 239,240 Pu (Bq kg -1 ) for selected northern atolls. Interpretation is also provided on the degree of contamination above global fallout levels. This report provides the first comprehensive summary of the radiological conditions throughout the Marshall Islands. 37 refs., 25 figs., 1 tab

  20. Distribution of cesium-137 in tree crop products collected from residence islands impacted by the U.S. nuclear test program in the northern Marshall Islands

    International Nuclear Information System (INIS)

    Peters, S.K.G.; Kehl, S.R.; Martinelli, R.E.; Tamblin, M.W.; Hamilton, T.F.

    2013-01-01

    The Marshall Islands Program at the Lawrence Livermore National Laboratory has completed a series of radiological surveys at Bikini, Rongelap, Utroek, and Enewetak Atolls in the Marshall Islands designed to take a representative sample of food supplies with emphasis on determining 137 Cs activity concentrations in common food plants. Coconuts (Cocos nucifera L.) are the most common and abundant food plant, and provided a common sample type to characterize the level and variability of activity concentrations of 137 Cs in plant foods collected from different islands and atolls. Other dominant food types included Pandanus (Pandanus spp.) and breadfruit (Actocarpus spp.). In general, the activity concentration of 137 Cs in food plants was found to decrease significantly between the main residence islands on Bikini, Rongelap, Utrōk, and Enewetak Atolls. The mean activity concentration of 137 Cs measured in drinking coconut meat and juice was 0.72 (95 % CI 0.68-0.77) and 0.34 (95 % CI 0.30-0.38) Bq g -1 , respectively, on Bikini Island; 0.019 (95 % CI 0.017-0.021) and 0.027 (95 % CI 0.023-0.031) Bq g -1 , respectively, on Rongelap Island; 0.010 (95 % CI 0.007-0.013) and 0.007 (95 % CI 0.004-0.009) Bq g -1 , respectively, on Utroek Island; and 0.002 (95 % CI 0.0013-0.0024) and 0.002 (95 % CI 0.001-0.0025) Bq g -1 , respectively, on Enewetak Island. High levels of variability are reported across all islands. These results will be used to improve the accuracy and reliability of predictive dose assessments, help characterize levels of uncertainty and variability in activity concentrations of fallout radionuclides in plant foods, and allow atoll communities to make informed decisions about resettlement and possible options for cleanup and rehabilitation of islands and atolls. (author)

  1. The decision-making process in returning relocated populations to the Marshall Islands

    International Nuclear Information System (INIS)

    Bell, T.

    1998-01-01

    Between 1946 and 1958, the United States conducted a nuclear weapons testing program in the northern Marshall Islands, detonating 66 nuclear weapons at Bikini and Enewetak. The indigenous populations at Bikini and Enewetak Atolls were evacuated prior to the initiation of testing at these respective atolls. Fallout in these cases were typically distributed within a few miles of the detonation. The 15-megaton thermonuclear Bravo device at Bikini resulted in the inadvertent deposition of radioactive fallout on the 253 inhabitants of Rongelap and Utirik atolls. The Rongelap and Utirik populations had not been evacuated prior to this test designed to detonate at about 5 megatons. 65 Rongelap individuals received whole body fallout doses of about 1.8 sievert (180 rem), 18 Ailinginae individuals received whole body doses of about 0.7 sievert (70 rem), and 157 Marshallese individuals at Utirik received a whole body fallout doses of about 0.14 sievert (14 rem.) The U.S. Department of Energy (DOE) and its predecessor agencies have provided special medical surveillance and treatment of radiation-related injury and illness for the surviving members of the populations of Rongelap and Utirik exposed during the 'Bravo' test. In addition, DOE conducts environmental and radiological monitoring and performs agricultural research studies to characterize the radioactivity remaining at the four atolls of Bikini in the aftermath of the 1946-58 U.S. nuclear testing program. (R.P.)

  2. Chromosome aberrations in Japanese fishermen exposed to fallout radiation 420-1200 km distant from the nuclear explosion test site at Bikini Atoll: report 60 years after the incident.

    Science.gov (United States)

    Tanaka, Kimio; Ohtaki, Megu; Hoshi, Masaharu

    2016-08-01

    During the period from March to May, 1954, the USA conducted six nuclear weapon tests at the "Bravo" detonation sites at the Bikini and Enewetak Atolls, Marshall Islands. At that time, the crew of tuna fishing boats and cargo ships that were operating approximately 150-1200 km away from the test sites were exposed to radioactive fallout. The crew of the fishing boats and those on cargo ships except the "5th Fukuryu-maru" did not undergo any health examinations at the time of the incident. In the present study, chromosome aberrations in peripheral blood lymphocytes were examined in detail by the G-banding method in 17 crew members from 8 fishing boats and 2 from one cargo ship, 60 years after the tests. None of the subjects examined had suffered from cancer. The percentages of both stable-type aberrations such as translocation, inversion and deletion, and unstable-type aberrations such as dicentric and centric ring in the study group were significantly higher (1.4- and 2.3-fold, respectively) than those in nine age-matched controls. In the exposed and control groups, the percentages of stable-type aberrations were 3.35 % and 2.45 %, respectively, and the numbers of dicentric and centric ring chromosomes per 100 cells were 0.35 and 0.15, respectively. Small clones were observed in three members of the exposed group. These results suggest that the crews were exposed to slightly higher levels of fallout than had hitherto been assumed.

  3. Day of two suns. US nuclear testing and the Pacific Islanders

    International Nuclear Information System (INIS)

    Dibblin, Jane.

    1988-01-01

    The book focuses on two Pacific communities affected by nuclear testing, the people of Rongelap atoll irradiated by fallout, and the people of Kwajalein atoll forced to leave their islands so it could be used as a target area for missiles launched from the western USA. Both atolls are part of the Marshall Islands which are on the eastern side of the groups of islands known as Micronesia. The USA conducted 66 nuclear tests in the period 1946-1958, one on Bikini Island, codenamed Bravo, causing the contamination of Rongelap. Following the halting of atmospheric nuclear explosions in 1958 the area became a missile testing target area. The reasons why the Marshall Islands were used, the effects of the fallout and destruction of the islanders way of life when they were moved from their homes is described. It draws widely on experience of the Marshall Islanders themselves. One of the appendices lists the tests and displacement in the Marshall Islands in chronological order. (U.K.)

  4. Effects of early childhood supplementation on the educational achievement of women.

    Science.gov (United States)

    Li, Haojie; Barnhart, Huiman X; Stein, Aryeh D; Martorell, Reynaldo

    2003-11-01

    Malnutrition during early childhood has been suggested to cause functional disadvantages in adults, including reduced intelligence and lower educational achievement (EA). We assessed the effects of improved nutrition in early life on the EA of women in 4 rural Guatemalan villages. The study sample comprised 130 female singletons exposed to either Atole (53%, 91 kcal and 6.4 g protein/100 mL) or Fresco (47%, 33 kcal/100 mL, no protein) during the prenatal period and the first 2 years of life. EA was assessed at the ages of 22 to 29 years by knowledge, numeracy, and several reading tests. A summary measure of EA was computed based on 5 tests, and outcome variables were categorized into quintiles. Analysis was based on a proportional odds model. Generalized estimating equations were used to account for sibling clustering. Overall, 36.2% of women completed primary school. Women exposed to Atole had better EA than those exposed to Fresco (odds ratio [OR]: 2.8; 95% confidence interval [CI], 1.4, 5.4), with a significant treatment-by-schooling interaction. Atole was not associated with EA (OR: 1.5; 95% CI: 0.7, 3.2) among women who did not complete primary school, whereas among those who completed primary school, Atole was associated with improved EA (OR: 13.7; 95% CI: 3.7, 50.8). We conclude that better nutrition during early childhood improved adult EA, but only among children who completed primary school.

  5. The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: two new species of Ramphotyphlops from the Caroline Islands

    Science.gov (United States)

    Wynn, Addison H.; Reynolds, Robert P.; Buden, Donald W.; Falanruw, Marjorie; Lynch, Brian

    2012-01-01

    Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R. adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excluding Ramphotyphlops braminus). Both species are unusual in being known only from small, low-lying atolls. They can be distinguished from other Ramphotyphlops by the combination of 22 scale rows over the length of the body; a wedge-shaped snout, without a keratinized keel; and a broad, pyriform (R. adocetus) or ovate (R. hatmaliyeb) rostral scale.

  6. Holocene emergence in the Cook Islands, South Pacific

    Science.gov (United States)

    Woodroffe, C. D.; Stoddart, D. R.; Spencer, T.; Scoffin, T. P.; Tudhope, A. W.

    1990-03-01

    There is evidence of Holocene emergence on several of the Cook Islands. On Suwarrow Atoll there are extensive outcrops of emergent, but truncated, reef on the northern atoll rim, radiocarbon-dated 4680 4310 years B. P., overlain by younger cemented boulder conglomerates. On the northeast of the atoll there are fossil algal ridges indicating up to 1 m of emergence; the landwardmost has been dated 4220 years B. P., the intermediate one 3420 years B. P. and the present one 1250 years B. P. On Mitiaro, a makatea island in the Southern Cooks, there are emergent reefal deposits in the centre of the reef flat dated 5140 3620 years B. P. Similar thought poorly preserved deposits occur on Mauke, and an erosional bench and notch occurs on Atiu. Emergence on all islands appears synchronous with that reported on Mangaia, where a relative fall of sea level of at least 1.7 m in the last 3400 years has been reported. The evidence for emergence is broadly similar to that described from French Polynesia, though timing of emergence appears to differ.

  7. Detection of cadmium radioactivity in the marine environment

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Anglin, D.L.

    1980-12-01

    Sediment and tissues from different marine organisms recently collected atolls of the Marshall Islands have been found to contain measurable amounts of /sup 113m/Cd previously deposited to the atolls during the testing of nuclear devices at the Pacific Proving Grounds. /sup 113m/Cd has been also detected in some internal organs of mullet collected from the east coast of the United States in an area contaminated only with global fallout debris. This is one of the few summaries to show that this long-lived radionuclide (T/sub 1/2/ = 14.6 yr) exists and persists in the marine environment. It is the dominant anthropogenic radionuclide in the liver of some pelagic fish from Bikini and Enewetak Atolls and is found concentrated in other tissues and organs of all fish analyzed. Dose to man from /sup 113m/Cd ingestion is being assessed at the Marshall Islands and should be done at any other global site where contamination by this radionuclide is suspected in the aquatic environment

  8. Doses from external irradiation to Marshall Islanders from Bikini and Enewetak nuclear weapons tests.

    Science.gov (United States)

    Bouville, André; Beck, Harold L; Simon, Steven L

    2010-08-01

    Annual doses from external irradiation resulting from exposure to fallout from the 65 atmospheric nuclear weapons tests conducted in the Marshall Islands at Bikini and Enewetak between 1946 and 1958 have been estimated for the first time for Marshallese living on all inhabited atolls. All tests that deposited fallout on any of the 23 inhabited atolls or separate reef islands have been considered. The methodology used to estimate the radiation doses at the inhabited atolls is based on test- and location-specific radiation survey data, deposition density estimates of 137Cs, and fallout times-of-arrival provided in a companion paper (Beck et al.), combined with information on the radionuclide composition of the fallout at various times after each test. These estimates of doses from external irradiation have been combined with corresponding estimates of doses from internal irradiation, given in a companion paper (Simon et al.), to assess the cancer risks among the Marshallese population (Land et al.) resulting from exposure to radiation from the nuclear weapons tests.

  9. Evaluation of Enewetak radioactivity containment. Final report

    International Nuclear Information System (INIS)

    1982-03-01

    Between 1948 and 1958 the Enewetak Atoll in the Marshall Islands was the site of 43 nuclear explosions, part of the government's nuclear testing program. Responding to the demands of the Enewetak people, the government in 1972 decided to rehabilitate the atoll. In the cleanup process, radiologically contaminated soil and debris from many of the atoll's islands were placed in a massive, domed concrete containment structure built over one of the bomb craters on Runit Island. In order to provide the people of Enewetak and the Marshallese Government with an objective assessment of the containment structure's safety, the Defense Nuclear Agency asked the Advisory Board on the Built Environment of the National Research Council to study the matter. The committee appointed to conduct the study concentrated on two issues: (1) the potential hazard of transuranics being transported to the surrounding environment from the structure, and (2) the possible sequence of events that would affect the structure's physical integrity, and the radioactive hazards that would result from breachment of the dome

  10. Detection of cadmium radioactivity in the marine environment

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Anglin, D.L.

    1981-01-01

    Sediment and tissues from different marine organisms recently collected at atolls of the Marshall Islands have been found to contain measurable amounts of 113 Cdsup(m) previously deposited to the atolls during the testing of nuclear devices at the Pacific Proving Grounds. Cadmium-113m has been also detected in some internal organs of mullet collected from the east coast of the United States of America in an area contaminated only with global fall-out debris. This is one of the few summaries to show that this long-lived radionuclide (Tsub(1/2) = 14.6 years) exists and persists in the marine environment. It is the dominate anthropogenic radionuclide in the liver of some pelagic fish from Bikini and Enewetak Atolls and is found concentrated in other tissues and organs of all fish analysed. Dose to man from 113 Cdsup(m) ingestion is being assessed at the Marshall Islands and should be carried out at any other global site where contamination by this radionuclide is suspected in the aquatic environment. (author)

  11. Characterization of an island aquifer from tidal response

    Science.gov (United States)

    Banerjee, Pallavi; Sarwade, Deepak; Singh, V. S.

    2008-08-01

    Growing demand for potable water for various needs has lead to indiscriminate exploitation of groundwater resources, particularly, in the terrain where surface water resources are negligible. One such area is an island where groundwater is the only source of fresh water. Groundwater is the prime source of fresh water on most of the atolls in the world. Groundwater on these islands is in the form of thin fragile floating lens and is often vulnerable to overexploitation, draught, tidal waves, tsunami and cyclone resulting in seawater ingress. Sustainable development of this meager source of fresh groundwater for a longer time becomes a more difficult task on small atolls with a large population depending on this vital resource. To develop a sustainable management scheme and identify the vulnerable part of aquifer, characterization of the aquifer system on islands is imperative. Groundwater on an atoll is extremely vulnerable to seawater mixing through natural as well as human activities. One such natural process is the tides of the ocean. The response of sea tide to the water table on the island offers valuable data as well as cost-effective means to characterize an aquifer system. Such characterization is vital for the management of groundwater resources on an atoll. The obtained results have compared well with the parameters obtained through a conventional pumping test. Therefore, the use of tidal response to the water table, which can easily be recorded, provides a rapid and cost-effective means to characterization of the aquifer system on the island.

  12. IAEA Newsbriefs. V. 13, no. 1(78). Jan-Feb 1998

    International Nuclear Information System (INIS)

    1998-01-01

    This issue gives brief information on the following topics: IAEA Board Meets in March, Director General ElBaradei Initiates Reviews, Nuclear Energy and Climate Change, States Honour Dr. Hans Blix, Radiological Conditions on Bikini Atoll Reassessed, Radiological Study of Mururoa and Fangataufa Atolls Nears Completion, Nuclear Inspections in Iraq, New Laboratory Set for Seibersdorf, Vienna Library Receives IAEA Collection, Developing Africa's Agricultural Economies, Marine Scientific Expedition to Northwest Pacific, Experts Target Radioactive Waste Management Needs in Russia, States Move to Accept Safeguards Protocol, In Memoriam, More States Sign Safety Convention, 1998 IAEA Scientific Meetings, New IAEA books, and other short information

  13. Dredging in the Spratly Islands: Gaining Land but Losing Reefs.

    Science.gov (United States)

    Mora, Camilo; Caldwell, Iain R; Birkeland, Charles; McManus, John W

    2016-03-01

    Coral reefs on remote islands and atolls are less exposed to direct human stressors but are becoming increasingly vulnerable because of their development for geopolitical and military purposes. Here we document dredging and filling activities by countries in the South China Sea, where building new islands and channels on atolls is leading to considerable losses of, and perhaps irreversible damages to, unique coral reef ecosystems. Preventing similar damage across other reefs in the region necessitates the urgent development of cooperative management of disputed territories in the South China Sea. We suggest using the Antarctic Treaty as a positive precedent for such international cooperation.

  14. The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site

    International Nuclear Information System (INIS)

    Robison, William L.; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

    2003-01-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ( 137 Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137 Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137 Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137 Cs and 90 Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137 Cs and 90 Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137 Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137 Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137 Cs/ 90 Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137 Cs/ 90 Sr ratios in soil in 1987 relative to the 137 Cs/ 90 Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on

  15. The effective and environmental half-life of 137Cs at Coral Islands at the former US nuclear test site.

    Science.gov (United States)

    Robison, William L; Conrado, Cynthia L; Bogen, Kenneth T; Stoker, A Carol

    2003-01-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 (137Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of 137Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of 137Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of 137Cs and 90Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of 137Cs and 90Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of 137Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the 137Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the 137Cs/90Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the 137Cs/90Sr ratios in soil in 1987 relative to the 137Cs/90Sr ratios at the time of deposition in 1954 is less than 17 years. The magnitude of the decrease below 17 years depends on the ELH for 90Sr

  16. Seawater-overwash impacts on freshwater-lens water supplies of low-lying oceanic islands: example from Roi-Namur Island, Kwajalein Atoll, Republic of the Marshall Islands

    Science.gov (United States)

    Voss, C. I.; Gingerich, S. B.

    2015-12-01

    Low-lying oceanic islands host thin freshwater lenses subject to long-term aquifer salinization by seawater overwash. The lens is often the sole-source water supply for inhabitants. As maximum elevation for these islands is only a few meters above sea level, overwash can occur during high tides and storm surges. Sea level rise due to climate change will make overwash events even more common. The thin freshwater lenses, a few meters thick, are underlain by seawater, so pumping must be done carefully, often with horizontal skimming wells. Even a small amount of downward seawater infiltration from an overwash event can render the water supply non-potable. Where permeability is high, seawater infiltrates quickly, but seawater that infiltrates lower-permeability zones may remain for many months causing groundwater to remain non-potable, leaving residents without a reliable freshwater source. Initial post-overwash salinization is driven by the higher density of the invading saltwater, which sinks and mixes into the fresher water in potentially-complex patterns determined by: distribution of flooding and post-flood ponding, locations of permeable paths, and the inherently complex flow fields generated when fluid of higher density overlies lower-density fluid. The flow patterns cannot generally be measured or predicted in detail. This study develops basic understanding of overwash salinization processes impacting water supply on low-level islands, using a rare example of a monitored seawater overwash event that occurred in December 2008 at Roi-Namur Island in Kwajalein Atoll, Republic of the Marshall Islands, in which the salinity evolution of well water was measured. Due to typical lack of field data on such islands, a set of plausible alternative simulation-model descriptions of the hydrogeology and overwash event are created for analysis of the monitored salinization and recovery. Despite inability to know the 'true and complete' description of the event and the

  17. Estimating the Impact of Drought on Groundwater Resources of the Marshall Islands

    Directory of Open Access Journals (Sweden)

    Brandon L. Barkey

    2017-01-01

    Full Text Available Groundwater resources of small coral islands are threatened due to short-term and long-term changes in climate. A significant short-term threat is El Niño events, which typically induce a severe months-long drought for many atoll nations in the western and central Pacific regions that exhausts rainwater supply and necessitates the use of groundwater. This study quantifies fresh groundwater resources under both average rainfall and drought conditions for the Republic of Marshall Islands (RMI, a nation composed solely of atolls and which is severely impacted by El Niño droughts. The atoll island algebraic model is used to estimate the thickness of the freshwater lens for 680 inhabited and uninhabited islands of the RMI, with a focus on the severe 1998 drought. The model accounts for precipitation, island width, hydraulic conductivity of the upper Holocene-age sand aquifer, the depth to the contact between the Holocene aquifer and the lower Pleistocene-age limestone aquifer, and the presence of a reef flat plate underlying the ocean side of the island. Model results are tested for islands that have fresh groundwater data. Results highlight the fragility of groundwater resources for the nation. Average lens thickness during typical seasonal rainfall is approximately 4 m, with only 30% of the islands maintaining a lens thicker than 4.5% and 55% of the islands with a lens less than 2.5 m thick. Thicker lenses typically occur for larger islands, islands located on the leeward side of an atoll due to lower hydraulic conductivity, and islands located in the southern region of the RMI due to higher rainfall rates. During drought, groundwater on small islands (<300 m in width is completely depleted. Over half (54% of the islands are classified as “Highly Vulnerable” to drought. Results provide valuable information for RMI water resources planners, particularly during the current 2016 El Niño drought, and similar methods can be used to quantify

  18. Sustainability of rainwater catchment systems for small island communities

    Science.gov (United States)

    Bailey, Ryan T.; Beikmann, Alise; Kottermair, Maria; Taboroši, Danko; Jenson, John W.

    2018-02-01

    Communities living on atolls and similar low-lying islands in the tropical Pacific rely on rainwater and shallow groundwater to meet domestic water needs. Rainwater, generally captured and stored using rooftop rainwater catchment systems, is the preferred water source due to higher quality and convenience of access. This study assesses the performance of rainwater catchment systems (RWCS) on Ifalik Atoll, located in Yap State, Federated States of Micronesia in the western Pacific. A field survey was conducted in August 2015 to evaluate RWCS features (guttered roof area, storage tank size, gutter leakage conditions), determine numbers of users, and estimate daily water use via household surveys. All 152 RWCS were surveyed. Water balance modeling was applied to the RWCS to estimate end-of-day stored rainwater volumes for each day of the 1997-1999 time period, during which an El Niño-induced drought occurred. Results indicate that the community is resilient to drought, although the majority of RWCS were depleted of rainwater and hence community sharing was required. Scenario testing indicates that increasing guttered roof area is the optimal strategy for enhancing system reliability. For example, the volume of water maintained at the peak of a drought can be tripled if the available roof areas for the RWCS are guttered. Design curves, which provide a set of roof area - tank volume combinations that achieve specified levels of reliability, were created and can be used to plan new RWCS. Besides offering insights into community-wide water storage and usage patterns and resiliency for Ifalik Atoll, this study presents methods that can be applied to other atoll island communities throughout the Indo-Pacific region.

  19. Radiological survey of plants, animals, and soil in micronesia

    International Nuclear Information System (INIS)

    Nelson, V.A.

    1975-11-01

    In 1974 the Laboratory of Radiation Ecology began a program to determine the radionuclides found in foods, plants, animals, and soils of the Central Pacific. As part of this program the present study was undertaken to determine radionuclides found in the common foods and soils in areas of Micronesia other than those areas receiving local fallout from the test sites at Bikini or Enewetak atolls. Areas sampled in 1975 were Majuro Atoll in the Marshall Islands, Truk and Ponape in the Caroline Islands, Guam in the Marianas Islands, and Koror and Babelthaup in the Palau Islands. All samples were analyzed for gamma-emitting radionuclides while some were also analyzed for 90 Sr of 239 240 Pu. Results of the analyses indicate that naturally occurring 40 K is the predominant radionuclide in the biological samples. Cesium-137 in amounts less than 1 pCi/g (dry) was the only fallout radionuclide detected in most of the biological samples. Soil samples usually contained 90 Sr, 137 Cs, 238 U, and 239 Pu, while soil from Truk, Palau, and Ponape also contained isotopes of radium and thorium. Soil from Guam also contained 210 Pb and 235 U in addition to the above radionuclides. Considering only the fallout radionuclides, the values for 90 Sr, 137 Cs, and 239 240 Pu in samples from Guam, Palau, Truk, Ponape, and Majuro are less than the values for these radionuclides in similar samples from atolls such as Utirik, Rongerik, and Ailinginae in the northern Marshall Islands, and are much less than values of these radionuclides in samples from Bikini and Rongelap atolls

  20. Improve services project -- Republic of the Marshall Islands.

    Science.gov (United States)

    Langidrik, J

    1995-01-01

    The Republic of the Marshall Islands has 60 dispensary sites, each staffed by 1 health assistant, to cover 80-800 people/site on 34 atolls. Until the spring of 1994, only curative services were available on a regular basis, and preventive services were provided by traveling health teams from the urban centers. In 1994, the health assistants in selected outer islands were trained to administer immunizations from vaccines which are sent regularly by air. Additional project sites are being selected. In 1993, 2 dispensaries initiated a project to 1) increase the number of women with access to prenatal care during the first trimester, 2) increase immunization levels, 3) improve access to preventive services, and 4) improve reporting and record-keeping systems. This project includes an important training component for the health assistant, the wife of the health assistant, the traditional birth attendant, the youth peer educator, community leaders, and a member of the local council. By 1994, this project was expanded to 13 dispensaries on 2 atolls. In 1995, 18 more dispensaries on 4 more atolls will be able to offer these additional services.

  1. The department of energy's environmental monitoring support for Rongelap resettlement in the Marshall Island: a partnership for the future

    International Nuclear Information System (INIS)

    Bell, T.R.

    2002-01-01

    The Department of Energy (DOE) initiated a dedicated program in 1974 to determine residual levels of contamination remaining in the Northern Marshall Islands from the 66 Pacific atmospheric nuclear weapons tests. The United States atmospheric nuclear weapons test code-named 'Castle BRAVO', conducted at the Bikini atoll in 1954, inadvertently deposited radioactive fallout on 253 residents of the Rongelap and Utrik atolls. The Rongelap people were evacuated 3 days after Castle Bravo, but not before they received significant fallout doses. Although the Rongelap people resettled on Rongelap Island from June 1957 until May 1985, the Rongelap community self-exiled themselves at that time for fear of what they believed to be rising levels of 137 Cs in their local food supplies. Since that time, the U.S. government has worked with the Rongelap people in a partnership to address environmental concerns and provide environmental monitoring, dose assessment data and information and mitigation strategy alternatives. DOE has been an instrumental partner in agreements, town meetings, interactions at the level of the local atoll government councils as well as the government of the Republic of the Marshall Islands have been needed to do this successfully. (author)

  2. Environmental protection

    International Nuclear Information System (INIS)

    Hull, A.P.

    1979-01-01

    Environmental Studies and Internal Dosimetry projects include: Environmental Protection; 1977 Environmental Monitoring Report; Sewage Sludge Disposal on the Sanitary Landfill; Radiological Analyses of Marshall Islands Environmental Samples, 1974 to 1976; External Radiation Survey and Dose Predictions for Rongelap, Utirik, Rongerik, Ailuk, and Wotje Atolls; Marshall Islands - Diet and Life Style Study; Dose Reassessment for Populations on Rongelap and Utirik Following Exposure to Fallout from BRAVO Incident (March 1, 1954); Whole Body Counting Results from 1974 to 1979 for Bikini Island Residents; Dietary Radioactivity Intake from Bioassay Data, a Model Applied to 137 Cs Intake by Bikini Island Residents; and External Exposure Measurements at Bikini Atoll

  3. The effective and environmental half-life of {sup 137}Cs at Coral Islands at the former US nuclear test site

    Energy Technology Data Exchange (ETDEWEB)

    Robison, William L. E-mail: robison1@llnl.gov; Conrado, Cynthia L.; Bogen, Kenneth T.; Stoker, A. Carol

    2003-07-01

    The United States (US) conducted nuclear weapons testing from 1946 to 1958 at Bikini and Enewetak Atolls in the northern Marshall Islands. Based on previous detailed dose assessments for Bikini, Enewetak, Rongelap, and Utirik Atolls over a period of 28 years, cesium-137 ({sup 137}Cs) at Bikini Atoll contributes about 85-89% of the total estimated dose through the terrestrial food chain as a result of uptake of {sup 137}Cs by food crops. The estimated integral 30, 50, and 70-year doses were based on the radiological decay of {sup 137}Cs (30-year half-life) and other radionuclides. However, there is a continuing inventory of {sup 137}Cs and {sup 90}Sr in the fresh water portion of the groundwater at all contaminated atolls even though the turnover rate of the fresh groundwater is about 5 years. This is evidence that a portion of the soluble fraction of {sup 137}Cs and {sup 90}Sr inventory in the soil is lost by transport to groundwater when rainfall is heavy enough to cause recharge of the lens, resulting in loss of {sup 137}Cs from the soil column and root zone of the plants. This loss is in addition to that caused by radioactive decay. The effective rate of loss was determined by two methods: (1) indirectly, from time-dependent studies of the {sup 137}Cs concentration in leaves of Pisonia grandis, Guettarda specosia, Tournefortia argentea (also called Messerschmidia), Scaevola taccada, and fruit from Pandanus and coconut trees (Cocos nucifera L.), and (2) more directly, by evaluating the {sup 137}Cs/{sup 90}Sr ratios at Bikini Atoll. The mean (and its lower and upper 95% confidence limits) for effective half-life and for environmental-loss half-life (ELH) based on all the trees studied on Rongelap, Bikini, and Enewetak Atolls are 8.5 years (8.0 years, 9.8 years), and 12 years (11 years, 15 years), respectively. The ELH based on the {sup 137}Cs/{sup 90}Sr ratios in soil in 1987 relative to the{sup 137}Cs/{sup 90}Sr ratios at the time of deposition in 1954 is less

  4. The Northern Marshall Islands radiological survey: Data and dose assessments

    International Nuclear Information System (INIS)

    Robison, W.L.; Noshkin, V.E.; Conrado, C.L.

    1997-01-01

    Fallout from atmospheric nuclear tests, especially from those conducted at the Pacific Proving Grounds between 1946 and 1958, contaminated areas of the Northern Marshall Islands. A radiological survey at some Northern Marshall Islands was conducted from September through November 1978 to evaluate the extent of residual radioactive contamination. The atolls included in the Northern Marshall Islands Radiological Survey (NMIRS) were Likiep, Ailuk, Utirik, Wotho, Ujelang, Taka, Rongelap, Rongerik, Bikar, Ailinginae, and Mejit and Jemo Islands. The original test sites, Bikini and Enewetak Atolls, were also visited on the survey. An aerial survey was conducted to determine the external gamma exposure rate. Terrestrial (soil, food crops, animals, and native vegetation), cistern and well water samples, and marine (sediment, seawater, fish and clams) samples were collected to evaluate radionuclide concentrations in the atoll environment. Samples were processed and analyzed for 137 Cs, 90 Sr, 239+240 Pu and 241 Am. The dose from the ingestion pathway was calculated using the radionuclide concentration data and a diet model for local food, marine, and water consumption. The ingestion pathway contributes 70% to 90% of the estimated dose. Approximately 95% of the dose is from 137 Cs accounts for about 10% to 30% of the dose. 239+240 Pu and 241 Am are the major contributors to dose via the inhalation pathway; however, inhalation accounts for only about 1% of the total estimated dose, based on surface soil levels and resuspension studies. All doses are computed for concentrations decay corrected to 1996. The maximum annual effective dose from manmade radionuclides at these atolls ranges from .02 mSv y -1 . The background dose in the Marshall Islands is estimated to be 2.4 mSv y -1 to 4.5 mSv y -1 . The 50-y integral dose ranges from 0.5 to 65 mSv. 35 refs., 2 figs., 9 tabs

  5. The consequences of underground nuclear testing in French Polynesia

    International Nuclear Information System (INIS)

    Brown, E.T.

    1998-01-01

    France began atmospheric nuclear testing at Mururoa and Fangataufa atolls in the South Pacific in July 1966. Following international protest, atmospheric testing ceased in August 1970. In late 1995, an International Geomechanical Commission (IGC) was created to assess the short- and long-term effects of underground nuclear testing on the stability and hydrology of Mururoa and Fangataufa. With the aid of its consultants, the Commission sought to develop its own understanding of the mechanics and consequences of the underground nuclear tests. It carried out extensive numerical analyses of shock wave effects, seismic wave propagation, slope stability and pre- and post-test hydrology. However, in its studies, the IGC was constrained to use the data made available to it by the French authorities. The Commission's report (International Geomechanical Commission 1998) has been submitted to the French Government. This article draws heavily on parts of that report. The Commission's observations and analyses show that there has been no apparent change, on the atoll scale, to the overall mechanical stability of either atoll as a consequence of the underground nuclear tests. The main observable consequences of the tests are underwater slope failures, open fractures on the rim surface and surface settlements. The fractures visible on the surface are generally associated with subsurface slope displacements and occur only in the carbonates. There is no evidence that slope failures or settlements have occurred in the underlying volcanics. There has been no significant change in the long-term (beyond 500 years) hydrology of either atoll. The IGC estimates that the long-term change in the natural groundwater flow will be no more than 1%. There are, however, significant short-term changes locally around the test sites, which are briefly outlined

  6. Tsunami survey expedition: preliminary investigation of Maldivian coral reefs two weeks after the event.

    Science.gov (United States)

    Goffredo, Stefano; Piccinetti, Corrado; Zaccanti, Francesco

    2007-08-01

    On December 26th 2004, a earthquake west of Sumatra generated a devastating tsunami. Hundreds of thousands of people fell victim. Economic losses were greatest in those countries dependant on tourism. The impact in the Maldives on persons and things was modest. Immediately following the event and notwithstanding the lack of scientific data, the mass media gave catastrophic reports on the state of coral reefs in the area. This paper reports on the first survey on coral reefs in the Maldives after the Tsunami. Ocean walls, passes, inner reefs, and shoals in the North and South Malé atolls, were surveyed two weeks after the event. Significant damage was recorded in the passes in the South Malé atoll. Our observations showed that the damage was more or less extensive depending on latitude and topography. Sri Lanka may have broken the wave's rush, reducing the extent of the impact on northern atolls. The water's acceleration inside the passes was so intense as to cause reef collapses. The observed damage represents a minimum fraction of the entire coral reef system. Tourist perception of the area seems unchanged. These data may be used to disseminate correct information about the state of Maldives coral reefs, which would be useful in relaunching local economy.

  7. Larval connectivity of pearl oyster through biophysical modelling; evidence of food limitation and broodstock effect

    Science.gov (United States)

    Thomas, Yoann; Dumas, Franck; Andréfouët, Serge

    2016-12-01

    The black-lip pearl oyster (Pinctada margaritifera) is cultured extensively to produce black pearls, especially in French Polynesia atoll lagoons. This aquaculture relies on spat collection, a process that experiences spatial and temporal variability and needs to be optimized by understanding which factors influence recruitment. Here, we investigate the sensitivity of P. margaritifera larval dispersal to both physical and biological factors in the lagoon of Ahe atoll. Coupling a validated 3D larval dispersal model, a bioenergetics larval growth model following the Dynamic Energy Budget (DEB) theory, and a population dynamics model, the variability of lagoon-scale connectivity patterns and recruitment potential is investigated. The relative contribution of reared and wild broodstock to the lagoon-scale recruitment potential is also investigated. Sensitivity analyses pointed out the major effect of the broodstock population structure as well as the sensitivity to larval mortality rate and inter-individual growth variability to larval supply and to the subsequent settlement potential. The application of the growth model clarifies how trophic conditions determine the larval supply and connectivity patterns. These results provide new cues to understand the dynamics of bottom-dwelling populations in atoll lagoons, their recruitment, and discuss how to take advantage of these findings and numerical models for pearl oyster management.

  8. White plague-like coral disease in remote reefs of the Western Caribbean

    Directory of Open Access Journals (Sweden)

    Juan A Sánchez

    2010-05-01

    Full Text Available The health of coral reef communities has been decreasing over the last 50 years, due the negative effects of human activities combined with other natural processes. We present documentation of a White Plague Disease (WPD outbreak in the Serrana Bank, an isolated Western Caribbean atoll with presumably inexistent pollutant inputs from local human settlements. In addition, this study summarizes seven years of observations on diseased corals in the nearby island of San Andrés, which in contrast is one of the most populated islands of the Caribbean. There was a massive coral mortality in the atoll lagoon (14°27’53.24", 80°14’22.27" W, and 12m depth due to WPD on May 4 of 2003. Seventeen species were found dead or largely affected by the disease. The information resulting from GPS and manta-tow transects revealed that approximately 5.8ha of reticulate Montastraea spp. patch reefs were lethally affected by the disease in the atoll. On May 8 of the same year we observed and calculated a mean coral cover of 7.03% (SD± 2.44, a mean diseased coral tissue cover of 5.5% (SD± 1.1 and a 13.4% (SD± 8.05 of recently dead coral covered with a thin filamentous algae layer; approximately 73% of mortalities caused by the disease occurred before the end of the outbreak. A rough estimate of 18.9% in recent coral cover reduction can be attributed to WPD. This represents about 82% of the total coral cover decline since 1995. Semi-enclosed environments such as atoll lagoons and the reticulate patch-reefs of Montastraea spp. seem to be particularly vulnerable to this kind of coral disease, which constitute an alert to increase the monitoring of the same kind of atoll environments. The WPD has been present in the area of the nearby island of San Andrés at a low prevalence level, with sporadic increasing peaks of disease proliferation. The peaks observed during 1999 and 2004 comprised increases of 266% and 355% respectively, suggesting an alarming progression of

  9. Technical papers presented at a DOE meeting on criteria for cleanup of transuranium elements in soil

    International Nuclear Information System (INIS)

    1984-09-01

    Transuranium element soil contamination cleanup experience gained from nuclear weapons accidents and cleanup at Eniwetok Atoll was reviewed. Presentations have been individually abstracted for inclusion in the data base

  10. Field trials at Bikini Atoll

    International Nuclear Information System (INIS)

    Robison, William L.; Stone, Earl L.

    1987-01-01

    Last year's report summarized the status of both the long on-going soil and plant sampling programs (initiated by LLNL in 1978) and the field experiments aimed at reducing radionuclide levels in food plants to acceptable levels. In the current report the two are combined into a single summary table, indicating for each field trial or survey the results to date, information expected by the spring of 1988, and projection, if any, for continuation beyond FY1988. This table is therefore a comprehensive survey of the program and accordingly the individual items in it have been coded to facilitate reference to them. Analytical results from field studies installed in 1985 and 1986 are now providing much new information, briefly described below. In part, these results bear out or enlarge the hypotheses that prompted the studies. They also suggest how some treatments may be modified or combined for greater effectiveness. We shall discuss here certain groups of studies of immediate interest that deal with the blocking effects of potassium and other ions on cesium-137 uptake by plants, the effect of removing topsoil (excavation), cultural studies which involve the manipulation of the subsoil, plus some others

  11. Field trials at Bikini Atoll

    Energy Technology Data Exchange (ETDEWEB)

    Robison, William L [Lawrence Livermore National Laboratory, Environmental Sciences Division, Livermore, CA (United States); Stone, Earl L [University of Florida, Soil Science Department, Gainesville, FL (United States)

    1987-07-01

    Last year's report summarized the status of both the long on-going soil and plant sampling programs (initiated by LLNL in 1978) and the field experiments aimed at reducing radionuclide levels in food plants to acceptable levels. In the current report the two are combined into a single summary table, indicating for each field trial or survey the results to date, information expected by the spring of 1988, and projection, if any, for continuation beyond FY1988. This table is therefore a comprehensive survey of the program and accordingly the individual items in it have been coded to facilitate reference to them. Analytical results from field studies installed in 1985 and 1986 are now providing much new information, briefly described below. In part, these results bear out or enlarge the hypotheses that prompted the studies. They also suggest how some treatments may be modified or combined for greater effectiveness. We shall discuss here certain groups of studies of immediate interest that deal with the blocking effects of potassium and other ions on cesium-137 uptake by plants, the effect of removing topsoil (excavation), cultural studies which involve the manipulation of the subsoil, plus some others.

  12. Failure Analysis of a Cracked UH-1 Tailboom Former, P/N 205-030-807-97

    National Research Council Canada - National Science Library

    Grendahl, Scott; Hardisky, Benjamin; Yocum, Russell

    2006-01-01

    .... Army Kwajalein Atoll Facility (USAKA) in the Marshall Islands for investigation. The component was being investigated due to the presence of cracks observed near bolt hole locations on the part...

  13. Le développement des îles-hôtels aux Maldives : d’hier à demain

    Directory of Open Access Journals (Sweden)

    Alexandre Magnan

    2010-09-01

    Full Text Available Les Maldives sont peuplées depuis plus de 2500 ans et leur nom viendrait du mot malodheep signifiant « guirlande » en sanskrit (Risk and Sluka, 2000. L’archipel compte en effet 26 atolls géographiques, classés en 19 atolls administratifs, qui s’étirent sur près de 800 km du nord au sud et 130 km d’est en ouest (figure 1. Les 1 200 îles répertoriées constituent une surface émergée totale de 297 km2 dont seulement 38 % sont habités par les 270 100 habitants que comptait le pays en 2000, soit ...

  14. Effects of a chemical weapons incineration plant on red-tailed tropicbirds

    Science.gov (United States)

    Schreiber, E.A.; Doherty, P.F.; Schenk, G.A.

    2001-01-01

    From 1990 to 2000, the Johnston Atoll Chemical Agent Disposal System (JACADS) incinerated part of the U.S. stockpile of chemical weapons on Johnston Atoll, central Pacific Ocean, which also is a National Wildlife Refuge and home to approximately a half-million breeding seabirds. The effect on wildlife of incineration of these weapons is unknown. Using a multi-strata mark-recapture analysis, we investigated the effects of JACADS on reproductive success, survival, and movement probabilities of red-tailed tropicbirds (Phaethon rubricauda) nesting both downwind and upwind of the incineration site. We found no effect of chemical incineration on these tropicbird demographic parameters over the 8 years of our study. An additional 3 years of monitoring tropicbird demography will take place, post-incineration.

  15. CRED Simrad em300 multibeam backscatter data of Howland Island, Pacific Remote Island Areas, Central Pacific in GeoTIFF format

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Multibeam backscatter imagery extracted from gridded bathymetry of the shelf and slope environments of Howland Atoll, Pacific Island Areas, Central Pacific. These...

  16. Video Records and Extracted Data - July 2005 HURL Cruise

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — First reconnaissance at Jarvis Island, Palmyra Atoll, and Kingman Reef, Line Islands, for species diversity, community structure, deep-water habitats, and bottom...

  17. Study of promotion of CO2 fixation by the environmental improvement in the coral reef area; Kansho chitai ni okeru kankyo kaizen ni yoru CO2 kotei sokushin no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Maruoka, T.; Ishitani, H.; Matsuhashi, R.; Yamada, K.; Komiyama, H.; Kraines, S. [The University of Tokyo, Tokyo (Japan). Faculty of Engineering

    1997-01-30

    A study was conducted on how to fix CO2 in the ocean using coral reefs. Coral reefs have extremely high primary productivity ( production quantity of organic matters by photosynthesis) and are expected to be resources to fix CO2 when the quantity of photosynthesis exceeds the quantity of CO2 emitted in association with formation of calcium carbonate skeleton. If organic substances produced in coral reefs are well carried into the open sea, those are settled down on deep beds, which enables the storage into the ocean. At the coral reef floating in the ocean, it is not very deep inside and the seawater stays there, but it has a steep depth outside. By the numerical calculation, an examination was made on how the waterflow changes when making the flow path of seawater between the inland sea and open sea. From the actual calculation of an atoll, it was found that seawater comes in and out from the open sea to the inland sea near the opening of the atoll in accordance with the high tide and ebb tide, but the water stays at the deep bottom of the atoll. When installing a channel with a 10m depth at the portion where the water flows softly, the seawater was actively exchanged. 6 refs., 4 figs.

  18. ON THE GEOMETRIC NATURE OF LOW-FREQUENCY QUASI-PERIODIC OSCILLATIONS IN NEUTRON-STAR LOW-MASS X-RAY BINARIES

    Energy Technology Data Exchange (ETDEWEB)

    Homan, Jeroen; Remillard, Ronald A. [MIT Kavli Institute for Astrophysics and Space Research, 77 Massachusetts Avenue 37-582D, Cambridge, MA 02139 (United States); Fridriksson, Joel K., E-mail: jeroen@space.mit.edu [Anton Pannekoek Institute for Astronomy, University of Amsterdam, Postbus 94249, 1090 GE Amsterdam (Netherlands)

    2015-10-10

    We report on a detailed analysis of the so-called ∼1 Hz quasi-periodic oscillation (QPO) in the eclipsing and dipping neutron-star low-mass X-ray binary EXO 0748–676. This type of QPO has previously been shown to have a geometric origin. Our study focuses on the evolution of the QPO as the source moves through the color–color diagram in which it traces out an atoll-source-like track. The QPO frequency increases from ∼0.4 Hz in the hard state to ∼25 Hz as the source approaches the soft state. Combining power spectra based on QPO frequency reveals additional features that strongly resemble those seen in non-dipping/eclipsing atoll sources. We show that the low-frequency QPOs in atoll sources and the ∼1 Hz QPO in EXO 0748–676 follow similar relations with respect to the noise components in their power spectra. We conclude that the frequencies of both types of QPOs are likely set by (the same) precession of a misaligned inner accretion disk. For high-inclination systems like EXO 0748–676 this results in modulations of the neutron-star emission due to obscuration or scattering, while for lower-inclination systems the modulations likely arise from relativistic Doppler-boosting and light-bending effects.

  19. Malnutrition, poverty and intellectual development.

    Science.gov (United States)

    Brown, J L; Pollitt, E

    1996-02-01

    New findings with important policy implications have revealed that malnutrition in childhood impairs intellectual function in more ways than was previously recognized, but also that some of the damage to the brain caused by malnutrition may be reversed. Early research indicated that malnourished animals lacked the energy to interact with their environment and, thus, performed poorly on tests of mental ability. To determine the effect of poor diet and an impoverished environment on mental development in humans, an extensive follow-up study was made of Guatemalan children who received two different nutritional supplements in a 1969-77 study. Mothers and children in two villages received a high-protein supplement (Atole), and those in two additional villages received a supplement with no protein (Fresco). Both supplements reduced mortality, but Atole villages saw a 69% reduction in infant mortality (vs. 24% in the Fresco villages). The 1988-89 follow-up of 70% of the original participants involved extensive cognitive testing and socioeconomic assessment. Atole subjects performed significantly better on the cognitive tests, and the lowest-income children did as well as their more economically advantaged (but still poor) peers. Those who received Atole exhibited an increased benefit from their years of education and grew up faster and stronger than those who received Fresco. Smaller children who appear younger than their age may receive less stimulation from adult expectations than larger children. These findings indicate that the deleterious effects of early malnutrition on intellectual development can continue into adulthood. Other research has revealed that iron supplements can improve the intellectual and motor abilities of infants. While enriched educational programs can ameliorate some of the problems associated with malnutrition, poor children rarely live where such programs are available. The best and least expensive policy would be to prevent malnutrition among

  20. Mass coral bleaching due to unprecedented marine heatwave in Papahānaumokuākea Marine National Monument (Northwestern Hawaiian Islands).

    Science.gov (United States)

    Couch, Courtney S; Burns, John H R; Liu, Gang; Steward, Kanoelani; Gutlay, Tiffany Nicole; Kenyon, Jean; Eakin, C Mark; Kosaki, Randall K

    2017-01-01

    2014 marked the sixth and most widespread mass bleaching event reported in the Northwestern Hawaiian Islands, home to the Papahānaumokuākea Marine National Monument (PMNM), the world's second largest marine reserve. This event was associated with an unusual basin-scale warming in the North Pacific Ocean, with an unprecedented peak intensity of around 20°C-weeks of cumulative heat stress at Lisianksi Island. In situ bleaching surveys and satellite data were used to evaluate the relative importance of potential drivers of bleaching patterns in 2014, assess the subsequent morality and its effects on coral communities and 3D complexity, test for signs of regional acclimation, and investigate long-term change in heat stress in PMNM. Surveys conducted at four island/atoll (French Frigate Shoals, Lisianski Island, Pearl and Hermes Atoll, and Midway Atoll) showed that in 2014, percent bleaching varied considerably between islands/atolls and habitats (back reef/fore reef and depth), and was up to 91% in shallow habitats at Lisianski. The percent bleaching during the 2014 event was best explained by a combination of duration of heat stress measured by Coral Reef Watch's satellite Degree Heating Week, relative community susceptibility (bleaching susceptibility score of each taxon * the taxon's abundance relative to the total number of colonies), depth and region. Mean coral cover at permanent Lisianski monitoring sites decreased by 68% due to severe losses of Montipora dilatata complex, resulting in rapid reductions in habitat complexity. Spatial distribution of the 2014 bleaching was significantly different from the 2002 and 2004 bleaching events likely due to a combination of differences in heat stress and local acclimatization. Historical satellite data demonstrated heat stress in 2014 was unlike any previous event and that the exposure of corals to the bleaching-level heat stress has increased significantly in the northern PMNM since 1982, highlighting the increasing

  1. Lessons from the Tōhoku tsunami: A model for island avifauna conservation prioritization

    Science.gov (United States)

    Reynolds, Michelle H.; Berkowitz, Paul; Klavitter, John; Courtot, Karen

    2017-01-01

    Earthquake-generated tsunamis threaten coastal areas and low-lying islands with sudden flooding. Although human hazards and infrastructure damage have been well documented for tsunamis in recent decades, the effects on wildlife communities rarely have been quantified. We describe a tsunami that hit the world's largest remaining tropical seabird rookery and estimate the effects of sudden flooding on 23 bird species nesting on Pacific islands more than 3,800 km from the epicenter. We used global positioning systems, tide gauge data, and satellite imagery to quantify characteristics of the Tōhoku earthquake-generated tsunami (11 March 2011) and its inundation extent across four Hawaiian Islands. We estimated short-term effects of sudden flooding to bird communities using spatially explicit data from Midway Atoll and Laysan Island, Hawai'i. We describe variation in species vulnerability based on breeding phenology, nesting habitat, and life history traits. The tsunami inundated 21%–100% of each island's area at Midway Atoll and Laysan Island. Procellariformes (albatrosses and petrels) chick and egg losses exceeded 258,500 at Midway Atoll while albatross chick losses at Laysan Island exceeded 21,400. The tsunami struck at night and during the peak of nesting for 14 colonial seabird species. Strongly philopatric Procellariformes were vulnerable to the tsunami. Nonmigratory, endemic, endangered Laysan Teal (Anas laysanensis) were sensitive to ecosystem effects such as habitat changes and carcass-initiated epizootics of avian botulism, and its populations declined approximately 40% on both atolls post-tsunami. Catastrophic flooding of Pacific islands occurs periodically not only from tsunamis, but also from storm surge and rainfall; with sea-level rise, the frequency of sudden flooding events will likely increase. As invasive predators occupy habitat on higher elevation Hawaiian Islands and globally important avian populations are concentrated on low-lying islands

  2. Evaluasi Performansi Jaringan UMTS di Kota Semarang menggunakan Metode Drive Test

    Directory of Open Access Journals (Sweden)

    HASANAH PUTRI

    2018-02-01

    Full Text Available ABSTRAK Saat ini penggunaan telepon seluler tidak hanya untuk komunikasi suara, melainkan juga untuk komunikasi data. Kota Semarang merupakan salah satu kota besar dengan jumlah pengguna telepon seluler yang banyak. Kondisi ini membutuhkan dukungan kualitas jaringan yang optimal dan kecepatan akses yang tinggi.  Pada penelitian ini dilakukan pengujian kualitas sinyal jaringan UMTS di kota tersebut. Pengukuran dilakukan dengan metode drive test menggunakan software TEMS dan Map info dalam pengolahan datanya. Ada beberapa parameter pengamatan dalam kegiatan pengukuran kualitas jaringan UMTS ini diantaranya RSCP (Receive Signal Code Power, Ec/No, Throughput dan KPI (Key Performance indicator. Setelah dilakukan pengukuran dan analisis perlu dilakukan proses simulasi optimasi yang dilakukan menggunakan software Atoll 3.2.1. Dari hasil pengukuran diperoleh nilai parameter RSCP, Ec/No, dan Throughput berturut-turut sebesar 68,45%, 91%, dan 52.2%. Setelah dilakukan simulasi optimasi terjadi peningkatan nilai parameter RSCP dan Ec/Noberturut-turut sebesar 97.28% dan 99.74%. Kata kunci: UMTS, Drive Test, Map Info, Atoll, KPI. ABSTRACT Today the use of mobile phone is not only for voice communication but also for data communications (mobile Internet. There are a lot of mobile phone users in Semarang, so that it requires the support of a good network quality and high-speed access. In this research, it will test and measure the signal quality UMTS network. The measurement is done with drive test method by using TEMS and Map Info software. There are several parameters of observation in quality measurement of UMTS network. They are RSCP (Received Signal Code Power, Ec/No , Throughput and KPI (Key Performance Indicator. After measurement and analysis it is needed to simulate the optimization recommendations process by using Atoll 3.2.1. to the observation’s parameters. From the measurement results obtained parameter values RSCP, Ec/No , and Throughput

  3. Evaluasi Performansi Jaringan UMTS di Kota Semarang menggunakan Metode Drive Test

    Directory of Open Access Journals (Sweden)

    HASANAH PUTRI

    2017-07-01

    Full Text Available ABSTRAKSaat ini penggunaan telepon seluler tidak hanya untuk komunikasi suara, melainkan juga untuk komunikasi data. Kota Semarang merupakan salah satu kota besar dengan jumlah pengguna telepon seluler yang banyak. Kondisi ini membutuhkan dukungan kualitas jaringan yang optimal dan kecepatan akses yang tinggi.  Pada penelitian ini dilakukan pengujian kualitas sinyal jaringan UMTS di kota tersebut. Pengukuran dilakukan dengan metode drive test menggunakan software TEMS dan Map info dalam pengolahan datanya. Ada beberapa parameter pengamatan dalam kegiatan pengukuran kualitas jaringan UMTS ini diantaranya RSCP (Receive Signal Code Power, Ec/No , Throughput dan KPI (Key Performance indicator. Setelah dilakukan pengukuran dan analisis perlu dilakukan proses simulasi optimasi yang dilakukan menggunakan software Atoll 3.2.1. Dari hasil pengukuran diperoleh nilai parameter RSCP, Ec/No , dan Throughput berturut-turut sebesar 68,45%, 91%, dan 52.2%. Setelah dilakukan simulasi optimasi terjadi peningkatan nilai parameter RSCP dan Ec/No berturut-turut sebesar 97.28% dan 99.74%.Kata kunci: UMTS, Drive Test, Map Info, Atoll, KPI.ABSTRACTToday the use of mobile phone is not only for voice communication but also for data communications (mobile Internet. There are a lot of mobile phone users in Semarang, so that it requires the support of a good network quality and high-speed access. In this research, it will test and measure the signal quality UMTS network. The measurement is done with drive test method by using TEMS and Map Info software. There are several parameters of observation in quality measurement of UMTS network. They are RSCP (Received Signal Code Power, Ec/No , Throughput and KPI (Key Performance Indicator. After measurement and analysis it is needed to simulate the optimization recommendations process by using Atoll 3.2.1. to the observation’s parameters. From the measurement results obtained parameter values RSCP, Ec/No , and Throughput

  4. Mass coral bleaching due to unprecedented marine heatwave in Papahānaumokuākea Marine National Monument (Northwestern Hawaiian Islands.

    Directory of Open Access Journals (Sweden)

    Courtney S Couch

    Full Text Available 2014 marked the sixth and most widespread mass bleaching event reported in the Northwestern Hawaiian Islands, home to the Papahānaumokuākea Marine National Monument (PMNM, the world's second largest marine reserve. This event was associated with an unusual basin-scale warming in the North Pacific Ocean, with an unprecedented peak intensity of around 20°C-weeks of cumulative heat stress at Lisianksi Island. In situ bleaching surveys and satellite data were used to evaluate the relative importance of potential drivers of bleaching patterns in 2014, assess the subsequent morality and its effects on coral communities and 3D complexity, test for signs of regional acclimation, and investigate long-term change in heat stress in PMNM. Surveys conducted at four island/atoll (French Frigate Shoals, Lisianski Island, Pearl and Hermes Atoll, and Midway Atoll showed that in 2014, percent bleaching varied considerably between islands/atolls and habitats (back reef/fore reef and depth, and was up to 91% in shallow habitats at Lisianski. The percent bleaching during the 2014 event was best explained by a combination of duration of heat stress measured by Coral Reef Watch's satellite Degree Heating Week, relative community susceptibility (bleaching susceptibility score of each taxon * the taxon's abundance relative to the total number of colonies, depth and region. Mean coral cover at permanent Lisianski monitoring sites decreased by 68% due to severe losses of Montipora dilatata complex, resulting in rapid reductions in habitat complexity. Spatial distribution of the 2014 bleaching was significantly different from the 2002 and 2004 bleaching events likely due to a combination of differences in heat stress and local acclimatization. Historical satellite data demonstrated heat stress in 2014 was unlike any previous event and that the exposure of corals to the bleaching-level heat stress has increased significantly in the northern PMNM since 1982, highlighting

  5. Seagrass habitat complexity and macroinvertebrate abundance in Lakshadweep coral reef lagoons, Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Ansari, Z.A.; Rivonker, C.U.; Ramani, P.; Parulekar, A.H.

    Macrofauna of seagrass community in the five Lakshadweep atolls were studied and compared. The associated epifaunal and infaunal taxa comprising nine major taxonomic groups, showed significant differences in the total number of individuals (1041...

  6. Improved nutrition in the first 1000 days and adult human capital and health.

    Science.gov (United States)

    Martorell, Reynaldo

    2017-03-01

    The aim of this article is to review why the first 1000 days of life are a vulnerable period of human development and the long-term effects of a nutrition experiment carried out in Guatemala (1969-1977). In 1969-77, a supplement called Atole, containing high quality protein, energy and micronutrients, was provided to women during pregnancy and lactation and to children nutritional requirements, greater susceptibility to infections, high sensitivity to programming effects and full dependence on others for care, nutrition, and social interaction. Compared with Fresco, Atole improved total nutrient intakes (protein, energy, and micronutrients) and reduced stunting, but only in children nutrition intervention. This provides a powerful argument for promoting improvements in nutrition in pregnant women and young children in low income countries. © 2017 Wiley Periodicals, Inc.

  7. Protection of marine birds and turtles at St Brandon's Rock, Indian ...

    African Journals Online (AJOL)

    Protection of marine birds and turtles at St Brandon's Rock, Indian Ocean, requires conservation of the entire atoll. SW Evans, N Cole, H Kylin, NS Choong Kwet Yive, V Tatayah, J Merven, H Bouwman ...

  8. Measurements and Counts for Larval and Juvenile Bramidae Specimens

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Micronekton and plankton samples were collected at the Southeast (SE) Hancock Seamount in 1985-1987, and in the vicinity of Palmyra Atoll, Line Islands in 1990....

  9. Pseudocyclops lakshmi, a new species (Pseudocyclopidae: Calanoidea: Copepoda) from the Laccadives, India

    Digital Repository Service at National Institute of Oceanography (India)

    Haridas, P.; Madhupratap, M.; Ohtsuka, S.

    Pseudocyclops lakshmi, new species, is described from the Kadmat and Agatti atolls of the Laccadives, India, along with its dimorphic males. Characters separating the new species from the rest of its congeners are discussed. This species...

  10. Final Environmental Assessment for Minuteman III Modification

    National Research Council Canada - National Science Library

    Huynh, Thomas; Kriz, Joseph; Lindman, Terry; Ramanujam, Ram

    2004-01-01

    .... The locations covered in this EA include: FE Warren Air Force Base (AFB), WY; Hill AFB, UT; Malmstrom AFB, MT; Minot AFB, ND; Vandenberg AFB, CA; and US Army Kwajalein Atoll, Republic of the Marshall Islands.

  11. @iPseudocyclops lakshmi@@, a new species (Pseudocyclopidae: Calanoidea: Copepoda) from the Laccadives, India

    Digital Repository Service at National Institute of Oceanography (India)

    Haridas, P.; Madhupratap, M.; Ohtsuka, S.

    @iPseudocyclops lakshmi@@, new species, is described from the Kadmat and Agatti atolls of the Laccadives, India, along with its dimorphic males. Characters separating the new species from the rest of its congeners are discussed. This species...

  12. Benthic Macroinvertebrate Community Assessment, Northwestern Hawaiian Islands, October 2000, (NODC Accession 0002301)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Northwestern Hawaiian lslands were sampled during October 2000 at 63 stations on 9 atolls or islands under the lead of NOAA. This work is affiliated with the...

  13. Monsoon induced cobalt enrichment in Porites (coral) from the Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.A.S.; Nath, B.N.

    Cobalt concentrations in growth bands of a reef building coral (Porites sp.) collected from Kalpeni Atoll of the Lakshadweep group of islands (Arabian Sea), rvealed that cobalt concentrations and Co/Ca ratios exhibit similar trend. Study indicates...

  14. Northwestern Hawaiian Islands Benthic Macroinvertebrate Community Assessment, 2000-10 (NODC Accession 0002301)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Northwestern Hawaiian islands were sampled during October 2000 at 63 stations on 9 atolls or islands under the lead of NOAA. This work is affiliated with the...

  15. Tarawa Stable Isotope (delta 18O, delta 13C) and Mineralogy Data for 1959 to 1979

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Site: Tarawa Atoll, Republic of Kiribati (1 deg N, 172 deg E). Water depth: 2-4m. Coral species Hydnophora microconos. Time span: 1959-79 at monthly resolution....

  16. 2004 INDIAN OCEAN TSUNAMI ON THE MALDIVES ISLANDS: INITIAL OBSERVATIONS

    Directory of Open Access Journals (Sweden)

    Barbara H. Keating

    2005-01-01

    Full Text Available Post-tsunami field surveys of the Maldives Islands where carried out to document the effects of the tsunami inundation. The study area was situated in the islands of South Male Atoll that were some of the most heavily damaged islands of the Maldive Islands. The tsunami damaged the natural environment, vegetation, man-made structures, and residents. The maximum tsunami wave height was 3-4 m. This level of inundation exceeded the height of most residents. The wave height was greatest on the eastern rim of the South Male Atoll (closest to the tsunami source and these islands were completely flooded. The islands within the interior of the atoll saw the lowest wave heights, and these were only marginally flooded.Surveys of flood lines left on the exterior and interior of structures were measured but proved to be substantially less than that reported by survivors. It appears that the highest inundation was not preserved as flood lines. We suggest that the turbulence associated with the tsunami inundation erased the highest lines or that they did not form due to an absence of debris and organic compounds that acted as adhesion during the initial flooding.Significant erosion was documented. Deposition took place in the form of sand sheets while only desultory deposition of coral clasts in marginal areas was found. Seasonal erosion, and storms are likely to remove most or all of the traces of the tsunami within these islands.

  17. Fusarium growth on culture media made of tissue juice from irradiated and unirradiated potato tubers

    International Nuclear Information System (INIS)

    Taczanowski, M.

    1994-01-01

    Fusarium Sulphureum Schlecht is one of the tuber pathogens causing potato storage disease knowing as dry rot. Because irradiation can disturb the tissue defence mechanism against the pathogen, it was decided to carry out experiments on influence of the treatment on subsequent tuber tissue reaction to a maceration process. The maceration as a physical stress was a substitute for the pathogen activity. Tubers of two potato varieties were tested: Mila -a resistant variety to Fusarium and Atol - susceptible one. Tubers of both varieties were irradiated with a dose of 105 kGy. Unirradiated tubers were taken as a control. A day after irradiation the cortex tissue was macerated using an ordinary rasper and the resulted tissue pulp was strained through medical gauze to obtain crude juice. The juice was clarified by centrifugation and then added to dissolved PDA. The volume ratio of juice to PDA was 1:1. The prepared media were dispensed into Petri dishes. Small pieces of the Fusarium culture were put on the surface of the medium at the centre of each Petri dish. Subsequent growth of the fungus was assessed by measurement of culture diameters every 24 hours. Linear functions of the Fusarium growth were obtained for Mila control and Atol control. In the case of Mila, the Fusarium found more favourable conditions for its growth in the presence of juice from irradiated tubers than from the control ones. Making the same comparison for Atol, no difference was detected. (author)

  18. Monsoon signatures in recent corals from the Laccadive Islands

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.A.S.

    X-radiographs of the coral (Porites sp.) collected from several atolls of Lakshadweep show alternate bands of low and high density, formed in non-monsoon period and monsoon period, respectively. The results reveal annual density variations as well...

  19. Defense Threat Reduction Agency > Contracts > Business Opportunities

    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  20. NTPR Radiation Exposure Reports

    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  1. Defense Threat Reduction Agency > Success Stories

    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  2. US Underground Nuclear Test History Reports

    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

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    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  4. NTPR Fact Sheets

    Science.gov (United States)

    History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Director Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  5. Eco-geomorphological zonation of the Bangaram reef, Lakshadweep

    Digital Repository Service at National Institute of Oceanography (India)

    Deshmukh, B.; Bahuguna, A.; Nayak, S.; Dhargalkar, V.K.; Jagtap, T.G.

    -morphological and ecological zones of the Bangaram reef (of atoll type), Lakshadweep islands, using remotely sensed data and adequately supported by field data. Classification system has been evolved to zone the reefs. Comparative studies have also been carried out using image...

  6. CRED Benthic Habitat Towboard Still Photos from Palmyra in March and April, 2004

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data is in the form of JPEG still photos taken every 15 seconds from a benthic habitat towboard being towed by small boats at Palmyra Atoll between March 26 and...

  7. 2005 EM300 and EM3002D Multibeam Sonar Data from Cruise Hi'ialakai HI-05-07 - Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — EM300 and EM3002D multibeam Data were collected from 08 August-01 October 2005 aboard NOAA Ship Hi'ialakai at Kure Atoll, Gambia Shoals, Pearl and Hermes Reef, west...

  8. Late medical consequences of exposure to radioactive fallout

    International Nuclear Information System (INIS)

    Adams, W.H.

    1992-01-01

    Data collected by the Brookhaven Medical Program on the late medical consequences of the exposure to radioactive fallout originated from the detonation of a thermonuclear device on Bikini atoll in Marshall Islands are discussed. (author) 23 refs.; 6 figs.; 9 tabs

  9. Midway Atoll Coastal Digital Elevation Model

    Data.gov (United States)

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

  10. The Northern Marshall Islands Radiological Survey: data and dose assessments.

    Science.gov (United States)

    Robison, W L; Noshkin, V E; Conrado, C L; Eagle, R J; Brunk, J L; Jokela, T A; Mount, M E; Phillips, W A; Stoker, A C; Stuart, M L; Wong, K M

    1997-07-01

    Fallout from atmospheric nuclear tests, especially from those conducted at the Pacific Proving Grounds between 1946 and 1958, contaminated areas of the Northern Marshall Islands. A radiological survey at some Northern Marshall Islands was conducted from September through November 1978 to evaluate the extent of residual radioactive contamination. The atolls included in the Northern Marshall Islands Radiological Survey (NMIRS) were Likiep, Ailuk, Utirik, Wotho, Ujelang, Taka, Rongelap, Rongerik, Bikar, Ailinginae, and Mejit and Jemo Islands. The original test sites, Bikini and Enewetak Atolls, were also visited on the survey. An aerial survey was conducted to determine the external gamma exposure rate. Terrestrial (soil, food crops, animals, and native vegetation), cistern and well water samples, and marine (sediment, seawater, fish and clams) samples were collected to evaluate radionuclide concentrations in the atoll environment. Samples were processed and analyzed for 137Cs, 90Sr, 239+240Pu and 241Am. The dose from the ingestion pathway was calculated using the radionuclide concentration data and a diet model for local food, marine, and water consumption. The ingestion pathway contributes 70% to 90% of the estimated dose. Approximately 95% of the dose is from 137Cs. 90Sr is the second most significant radionuclide via ingestion. External gamma exposure from 137Cs accounts for about 10% to 30% of the dose. 239+240Pu and 241Am are the major contributors to dose via the inhalation pathway; however, inhalation accounts for only about 1% of the total estimated dose, based on surface soil levels and resuspension studies. All doses are computed for concentrations decay corrected to 1996. The maximum annual effective dose from manmade radionuclides at these atolls ranges from .02 mSv y(-1) to 2.1 mSv y(-1). The background dose in the Marshall Islands is estimated to be 2.4 mSv y(-1). The combined dose from both background and bomb related radionuclides ranges from slightly

  11. Acute and chronic intakes of fallout radionuclides by Marshallese from nuclear weapons testing at Bikini and Enewetak and related internal radiation doses.

    Science.gov (United States)

    Simon, Steven L; Bouville, André; Melo, Dunstana; Beck, Harold L; Weinstock, Robert M

    2010-08-01

    Annual internal radiation doses resulting from both acute and chronic intakes of all important dose-contributing radionuclides occurring in fallout from nuclear weapons testing at Bikini and Enewetak from 1946 through 1958 have been estimated for the residents living on all atolls and separate reef islands of the Marshall Islands. Internal radiation absorbed doses to the tissues most at risk to cancer induction (red bone marrow, thyroid, stomach, and colon) have been estimated for representative persons of all population communities for all birth years from 1929 through 1968, and for all years of exposure from 1948 through 1970. The acute intake estimates rely on a model using, as its basis, historical urine bioassay data, for members of the Rongelap Island and Ailinginae communities as well as for Rongerik residents. The model also utilizes fallout times of arrival and radionuclide deposition densities estimated for all tests and all atolls. Acute intakes of 63 radionuclides were estimated for the populations of the 20 inhabited atolls and for the communities that were relocated during the testing years for reasons of safety and decontamination. The model used for chronic intake estimates is based on reported whole-body, urine, and blood counting data for residents of Utrik and Rongelap. Dose conversion coefficients relating intake to organ absorbed dose were developed using internationally accepted models but specifically tailored for intakes of particulate fallout by consideration of literature-based evidence to choose the most appropriate alimentary tract absorption fraction (f1) values. Dose estimates were much higher for the thyroid gland than for red marrow, stomach wall, or colon. The highest thyroid doses to adults were about 7,600 mGy for the people exposed on Rongelap; thyroid doses to adults were much lower, by a factor of 100 or more, for the people exposed on the populated atolls of Kwajalein and Majuro. The estimates of radionuclide intake and

  12. Statistical properties of twin kilohertz quasi-periodic oscillations neutron star low-mass X-ray binaries

    Science.gov (United States)

    Wang, D. H.; Chen, L.; Zhang, C. M.; Lei, Y. J.; Qu, J. L.

    2014-02-01

    We collect the data of twin kilohertz quasi-periodic oscillations (kHz QPOs) published before 2012 from 26 neutron star (NS) low-mass X-ray binary (LMXB) sources, then we analyze the centroid frequency (ν) distribution of twin kHz QPOs (lower frequency ν_1 and upper frequency ν_2) both for Atoll and Z sources. For the data without shift-and-add, we find that Atoll and Z sources show different distributions of ν_1, ν_2 and ν_2/ν_1, but the same distribution of Δν (difference of twin kHz QPOs), which indicates that twin kHz QPOs may share the common properties of LXMBs and have the same physical origins. The distribution of Δν is quite different from a constant value, so is ν_2/ν_1 from a constant ratio. The weighted mean values and maxima of ν_1 and ν_2 in Atoll sources are slightly higher than those in Z sources. We also find that shift-and-add technique can reconstruct the distributions of ν_1 and Δν. The K-S test results of ν_1 and Δν between Atoll and Z sources from data with shift-and-add are quite different from those without it, and we think that this may be caused by the selection biases of the sample. We also study the properties of the quality factor (Q) and the root-mean-squared (rms) amplitude of 4U 0614+09 with data from the two observational methods, but the errors are too big to make a robust conclusion. The NS spin frequency (ν_s) distribution of 28 NS-LMXBs show a bigger mean value (˜ 408 Hz) than that (˜ 281 Hz) of the radio binary millisecond pulsars (MSPs), which may be due to the lack of the spin detections from Z sources (systematically lower than 281 Hz). Furthermore, on the relations between the kHz QPOs and NS spin frequency ν_s, we find the approximate correlations of the mean values of Δν with NS spin and its half, respectively.

  13. Defense Threat Reduction Agency > Contracts > Business Opportunities >

    Science.gov (United States)

    Atmospheric Nuclear Test History Documents US Underground Nuclear Test History Reports NTPR Radiation Exposure Reports Enewetak Atoll Cleanup Documents TRAC About Who We Are Our Values History Locations Our Leadership Support Center Contact Us FAQ Sheet Links Success Stories Contracts Business Opportunities Current

  14. 75 FR 71737 - Energy Employees Occupational Illness Compensation Program Act of 2000, as Amended

    Science.gov (United States)

    2010-11-24

    ... Facilities Pacific Proving Ground Bikini and Enewetak Atolls (now 1946-1962. Republic of the Marshall Islands... Facilities Exclusively Facility name Location Dates Alaska DOE Facilities Amchitka Nuclear Explosion Site... Nuclear Explosion Site.. Rifle 1973-1976. Project Rulison Nuclear Explosion Site..... Grand Valley 1969...

  15. CRED Gridded Bathymetry of Northwest Gardner Pinnacles (100-011) in the Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-011b is a 60-m ASCII grid of depth data collected near Kure Atoll in the Northwestern Hawaiian Islands as of May 2003. This grid has been produced as part...

  16. CRED Gridded Bathymetry near Northampton Seamounts to West Laysan Island (100-005) Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-005b is a 60-m ASCII grid of depth data collected near Kure Atoll in the Northwestern Hawaiian Islands as of May 2003. This grid has been produced as part...

  17. CRED Gridded Bathymetry of West St. Rogatien Bank (100-017) in the Northwestern Hawaiian Islands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — File 100-017b is a 60-m ASCII grid of depth data collected near Kure Atoll in the Northwestern Hawaiian Islands as of May 2003. This grid has been produced as part...

  18. Single and Coupled Nanobeam Cavities

    DEFF Research Database (Denmark)

    Ivinskaya, Aliaksandra; Lavrinenko, Andrei; Shyroki, Dzmitry M.

    2013-01-01

    for analysis and design of photonic crystal devices, such as 2D ring resonators for filters, single and coupled nanobeam cavities, birefringence in photonic crystal cavities, threshold analysis in photonic crystal lasers, gap solitons in photonic crystals, novel photonic atolls, dynamic characteristics...

  19. 21st Century Rise in Anthropogenic Nitrogen Deposition on a Remote Coral Reef

    Science.gov (United States)

    Ren, H. A.; Chen, Y. C.; Wang, X. T.; Wong, G. T. F.; Cohen, A. L.; DeCarlo, T. M.; Weigand, M. A.; Mii, H. S.; Sigman, D. M.

    2017-12-01

    With the rapid rise in pollution-associated nitrogen inputs to the western Pacific, it has been suggested that even the open ocean has been impacted through atmospheric deposition. In a coral core from Dongsha Atoll, a coral reef ecosystem 340 km from the nearest continent, we observe a decline in the 15N/14N of coral skeleton-bound organic matter, signaling increased deposition of anthropogenic atmospheric N on the open ocean and its incorporation into plankton and in turn the corals living on the atoll. The decrease began just several years before 2000 CE, decades later than predicted by other work, and the amplitude of decline suggests that anthropogenic atmospheric N input is now 20±5% of the annual N input to the surface ocean in this region, less than two-thirds of that estimated by models and analyses of nutrient ratio changes.

  20. Comparative study of plutonium and americium bioaccumulation from two marine sediments contaminated in the natural environment

    International Nuclear Information System (INIS)

    Hamilton, T.F.; Smith, J.D.

    1991-01-01

    Plutonium and americium sediment-animal transfer was studied under controlled laboratory conditions by exposure of the benthic polychaete Nereis diversicolor (O. F. Mueller) to marine sediments contaminated by a nuclear bomb accident (near Thule, Greenland) and nuclear weapons testing (Enewetak Atoll). In both sediment regimes, the bioavailability of plutonium and 241 Am was low, with specific activity in the tissues 241 Am occurred and 241 Am uptake from the Thule sediment was enhanced compared to that from lagoon sediments of Enewetak Atoll. Autoradiography studies indicated the presence of hot particles of plutonium in the sediments. The results highlight the importance of purging animals of their gut contents in order to obtain accurate estimates of transuranic transfer from ingested sediments into tissue. It is further suggested that enhanced transuranic uptake by some benthic species could arise from ingestion of highly activity particles and organic-rich detritus present in the sediments. (author)

  1. The Drop of the Coherence of the Lower Kilohertz Quasi-periodic Brightness Variations is Also Observed in XTE J1701-462

    Science.gov (United States)

    Barret, D.; Bachetti, M.; Miller, M. Coleman

    2011-02-01

    We investigate the quality factor and root mean square (rms) amplitude of the lower kilohertz quasi-periodic brightness variations (kHz QPOs) from XTE J1701-462, a unique X-ray source which was observed in both the so-called Z and atoll states. Correcting for the frequency drift of the QPO, we show that, as in all sources for which such a correction can be applied, the quality factor and rms amplitude drops sharply above a critical frequency. For XTE J1701-462, this frequency is estimated to be ~800 Hz, where the quality factor reaches a maximum of ~200 (e.g., a value consistent with the one observed from more classical systems, such as 4U 1636-536). Such a drop has been interpreted as the signature of the innermost stable circular orbit, and that interpretation is consistent with the observations we report here. The kHz QPOs in the Z state are much less coherent and lower amplitude than they are in the atoll state. We argue that the change of the QPO properties between the two source states is related to the change of the scale height of the accretion disk; a prediction of the toy model proposed by Barret et al. As a by-product of our analysis, we also increased the significance of the upper kHz QPO detected in the atoll phase up to 4.8σ (single trial significance) and show that the frequency separation (266.5 ± 13.1 Hz) is comparable with the one measured from simultaneous twin QPOs in the Z phase.

  2. Preliminary socioeconomic and community planning studies

    Energy Technology Data Exchange (ETDEWEB)

    Rivkin, Goldie W; Rivkin, Malcolm D [Rivkin Associates, Bethesda, MD (United States)

    1986-07-01

    The timing of resettlement on Bikini Atoll and the nature of a master plan to guide construction of a new community depend on four critical determinants which are not yet definitively known. The Bikini Atoll Rehabilitation Committee (BARC) and its consultants have been addressing three of these: a. How long it will take to restore Bikini Island, which will be the main settlement area, to a habitable state. The methods under investigation by BARC for decontaminating the island might be considered as alternatives or, possibly in combination. They vary considerably, not only with respect to cost, but also with respect to important factors such as: - how long it will take to decontaminate the island (i.e. to reduce radiation to levels acceptable within Federal standards), - the necessity of removing existing vegetation and the time and effort needed to restore environment and vegetation to a state sufficient to support a new community at a reasonable standard of amenity, - requirements for repeated or continual application of decontamination procedures (and associated risks), and - implications for potential constraints on the lifestyle of the people who resettle on Bikini Island. b. Adequacy of water resources (groundwater and rainwater catchment potential) on Bikini and Eneu Islands to support both revegetation as necessary, and a new community. c. The likely state of the Bikini people (size of the population, location(s), living conditions, financial commitments, etc.) at the time their atoll is ready for resettlement. d. The judgment and wishes of the Bikini people regarding a community plan in light of all the foregoing factors, once they become known.

  3. EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES

    International Nuclear Information System (INIS)

    Lei Yajuan; Zhang Haotong; Zhang Chengmin; Yuan Hailong; Dong Yiqiao; Zhao Yongheng; Zhang Yanxia; Qu Jinlu; Song Liming; Wang Dehua; Yin Hongxing

    2013-01-01

    We analyze the cross-correlation function between the soft and hard X-rays of atoll source 4U 1735-44 with RXTE data, and find anti-correlated soft and hard time lags of about a hecto-second. In the island state, the observations do not show any obvious correlations, and most observations of the banana branch show a positive correlation. However, anti-correlations are detected in the upper banana branch. These results are different from those of Z-sources (Cyg X-2, GX 5-1), where anti-correlations are detected in the horizontal branch and upper normal branch. In this case, the lag timescales of both this atoll and Z-sources are found to be similar, at a magnitude of several tens to hundreds of seconds. As a comparison, it is noted that anti-correlated lags lasting thousands of seconds have been reported from several black hole candidates in their intermediate states. In addition, for an observation containing four segments that show positive or anti-correlation, we analyze the spectral evolution with the hybrid model. In the observation, the anti-correlation is detected at the highest flux. The fitting results show that the Comptonized component is not the lowest at the highest flux, which suggests that the anti-correlation corresponds to the transition between the soft and hard states. Finally, we compare the corresponding results of atoll source 4U 1735-44 with those observed in Z-sources and black hole candidates, and the possible origins of the anti-correlated time lags are discussed

  4. EVOLUTION OF THE CROSS-CORRELATION AND TIME LAG OF 4U 1735-44 ALONG THE BRANCHES

    Energy Technology Data Exchange (ETDEWEB)

    Lei Yajuan; Zhang Haotong; Zhang Chengmin; Yuan Hailong; Dong Yiqiao; Zhao Yongheng; Zhang Yanxia [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China); Qu Jinlu; Song Liming [Particle Astrophysics Center, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); Wang Dehua [Astronomy Department, Beijing Normal University, Beijing 100875 (China); Yin Hongxing, E-mail: leiyjcwmy@163.com [School of Space Science and Physics, Shandong University, Weihai 264209 (China)

    2013-09-15

    We analyze the cross-correlation function between the soft and hard X-rays of atoll source 4U 1735-44 with RXTE data, and find anti-correlated soft and hard time lags of about a hecto-second. In the island state, the observations do not show any obvious correlations, and most observations of the banana branch show a positive correlation. However, anti-correlations are detected in the upper banana branch. These results are different from those of Z-sources (Cyg X-2, GX 5-1), where anti-correlations are detected in the horizontal branch and upper normal branch. In this case, the lag timescales of both this atoll and Z-sources are found to be similar, at a magnitude of several tens to hundreds of seconds. As a comparison, it is noted that anti-correlated lags lasting thousands of seconds have been reported from several black hole candidates in their intermediate states. In addition, for an observation containing four segments that show positive or anti-correlation, we analyze the spectral evolution with the hybrid model. In the observation, the anti-correlation is detected at the highest flux. The fitting results show that the Comptonized component is not the lowest at the highest flux, which suggests that the anti-correlation corresponds to the transition between the soft and hard states. Finally, we compare the corresponding results of atoll source 4U 1735-44 with those observed in Z-sources and black hole candidates, and the possible origins of the anti-correlated time lags are discussed.

  5. Preliminary socioeconomic and community planning studies

    International Nuclear Information System (INIS)

    Rivkin, Goldie W.; Rivkin, Malcolm D.

    1986-01-01

    The timing of resettlement on Bikini Atoll and the nature of a master plan to guide construction of a new community depend on four critical determinants which are not yet definitively known. The Bikini Atoll Rehabilitation Committee (BARC) and its consultants have been addressing three of these: a. How long it will take to restore Bikini Island, which will be the main settlement area, to a habitable state. The methods under investigation by BARC for decontaminating the island might be considered as alternatives or, possibly in combination. They vary considerably, not only with respect to cost, but also with respect to important factors such as: - how long it will take to decontaminate the island (i.e. to reduce radiation to levels acceptable within Federal standards), - the necessity of removing existing vegetation and the time and effort needed to restore environment and vegetation to a state sufficient to support a new community at a reasonable standard of amenity, - requirements for repeated or continual application of decontamination procedures (and associated risks), and - implications for potential constraints on the lifestyle of the people who resettle on Bikini Island. b. Adequacy of water resources (groundwater and rainwater catchment potential) on Bikini and Eneu Islands to support both revegetation as necessary, and a new community. c. The likely state of the Bikini people (size of the population, location(s), living conditions, financial commitments, etc.) at the time their atoll is ready for resettlement. d. The judgment and wishes of the Bikini people regarding a community plan in light of all the foregoing factors, once they become known

  6. Measurement of background gamma radiation in the northern Marshall Islands.

    Science.gov (United States)

    Bordner, Autumn S; Crosswell, Danielle A; Katz, Ainsley O; Shah, Jill T; Zhang, Catherine R; Nikolic-Hughes, Ivana; Hughes, Emlyn W; Ruderman, Malvin A

    2016-06-21

    We report measurements of background gamma radiation levels on six islands in the northern Marshall Islands (Enewetak, Medren, and Runit onEnewetak Atoll; Bikini and Nam on Bikini Atoll; and Rongelap on Rongelap Atoll). Measurable excess radiation could be expected from the decay of (137)Cs produced by the US nuclear testing program there from 1946 to 1958. These recordings are of relevance to safety of human habitation and resettlement. We find low levels of gamma radiation for the settled island of Enewetak [mean = 7.6 millirem/year (mrem/y) = 0.076 millisievert/year (mSv/y)], larger levels of gamma radiation for the island of Rongelap (mean = 19.8 mrem/y = 0.198 mSv/y), and relatively high gamma radiation on the island of Bikini (mean = 184 mrem/y = 1.84 mSv/y). Distributions of gamma radiation levels are provided, and hot spots are discussed. We provide interpolated maps for four islands (Enewetak, Medren, Bikini, and Rongelap), and make comparisons to control measurements performed on the island of Majuro in the southern Marshall Islands, measurements made in Central Park in New York City, and the standard agreed upon by the United States and the Republic of the Marshall Islands (RMI) governments (100 mrem/y = 1 mSv/y). External gamma radiation levels on Bikini Island significantly exceed this standard (P = <0.01), and external gamma radiation levels on the other islands are below the standard. To determine conclusively whether these islands are safe for habitation, radiation exposure through additional pathways such as food ingestion must be considered.

  7. 78 FR 20950 - Department of Energy Facilities Covered Under the Energy Employees Occupational Illness...

    Science.gov (United States)

    2013-04-08

    ... 1946-1962. Enewetak Atolls (now part of the Republic of the Marshall Islands), Johnston Island and... Exclusively Facility name Location Dates Amchitka Island Nuclear Amchitka Island... 1965-9/1973; 5/25... Nuclear Rifle 1973-1976. Explosion Site. Project Rulison Nuclear Grand Valley...... 1969-1971; 1972...

  8. Fall-out of military nuclear explosions: Marshall Islands, Utah and Nevada states

    International Nuclear Information System (INIS)

    Galle, P.

    1992-01-01

    In this article, the author presents 1954 Bikini atoll accident and early and delayed effects on population: non thyroid and thyroid effects (hypothyroidism, nodules) in according to age, radiation doses. In conclusion, the most of late complications are induced by iodine radioisotopes. (5 tabs)

  9. Engaged World-Making

    DEFF Research Database (Denmark)

    Robertson, Maria Louise Bønnelykke; Rubow, Cecilie

    2013-01-01

    Drawing on fieldwork in Kiribati and the Cook Islands, this chapter shows how atoll islands and tropical lagoons, considered highly vulnerable to present and future sea level rise, are extraordinary malleable socio-natural worlds. Revolving around sacred islands submerged by sea water, ancient fi...

  10. 50 CFR 32.71 - United States Unincorporated Pacific Insular Possessions.

    Science.gov (United States)

    2010-10-01

    .... Migratory Game Bird Hunting. [Reserved] B. Upland Game Hunting. [Reserved] C. Big Game Hunting. [Reserved] D. Sport Fishing. [Reserved] Midway Atoll National Wildlife Refuge A. Migratory Game Bird Hunting. [Reserved] B. Upland Game Hunting. [Reserved] C. Big Game Hunting. [Reserved] D. Sport Fishing. [Reserved...

  11. Scleractinian corals (Fungiidae, Agariciidae and Euphylliidae) of Pulau Layang-Layang, Spratly Islands, with a note on Pavona maldivensis (Gardiner, 1905)

    KAUST Repository

    Waheed, Zarinah; Benzoni, Francesca; van der Meij, Sancia E. T.; Terraneo, Tullia Isotta; Hoeksema, Bert W.

    2015-01-01

    Layang-Layang is a small island part of an oceanic atoll in the Spratly Islands off Sabah, Malaysia. As the reef coral fauna in this part of the South China Sea is poorly known, a survey was carried out in 2013 to study the species composition

  12. Book reviews

    NARCIS (Netherlands)

    Steenis, van C.G.G.J.; Steenis, van C.G.G.J.; Steenis, van C.G.G.J.; Steenis, van C.G.G.J.; Steenis, van C.G.G.J.

    1951-01-01

    Survey of the flora of Bikini and other atolls before the atomic-bomb tests were made. The phytoplancton is excluded from the present carefully written and extensive analysis, which is most instructive to every student of tropical coral island floras. A general introduction furnishes an excellent

  13. The unexpected discovery of blind snakes (Serpentes: Typhlopidae) in Micronesia: two new species of Ramphotyphlops from the Caroline Islands

    Science.gov (United States)

    Addison H. Wynn; Robert P. Reynolds; Donald W. Buden; Marjorie Falanruw; Brian. Lunch

    2012-01-01

    Two new blind snakes in the genus Ramphotyphlops are described from Ulithi (R. hatmaliyeb sp. nov.) and Ant Atoll (R.adocetus sp. nov.) in the Caroline Islands, the first blind snake species known from Micronesia east of Palau (excludingRamphotyphlops braminus). Both species are unusual in...

  14. Concentrations of sup(113m)Cd in the marine environment

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Anglin, D.L.

    1980-01-01

    A preliminary report is presented of sup(113m)Cd concentrations measured in sediment and tissue samples of marine organisms collected around different atols in the Marshall Islands which are considered to be representative of the levels expected at these latitudes from global fallout deposition. (U.K.)

  15. Information Withholding as a Manipulative and Collusive Strategy in Nukulaelae Gossip.

    Science.gov (United States)

    Besnier, Niko

    1989-01-01

    Examines the organization and function of information-withholding sequences, a conversational strategy used by participants in gossip interaction on Nukulaelae, a Polynesian Central Pacific atoll. Withholding sequences illustrate how ambiguity and repairs can be exploited to meet the communicative demands of particular interactional contexts. (62…

  16. Low Frequency Quasi-periodic Oscillations in the High-eccentric LMXB Cir X-1: Extending the WK Correlation for Z Sources

    Energy Technology Data Exchange (ETDEWEB)

    Bu, Qingcui; Chen, Li [Department of Astronomy, Beijing Normal University, Beijing 100875 (China); Belloni, T. M. [INAF-Osservatorio Astronomico di Brera, Via E, Bianchi 46, I-23807 Merate (Italy); Qu, Jinlu, E-mail: buqc@mail.bnu.edu.cn, E-mail: tomaso.belloni@brera.inaf.it, E-mail: chenli@bnu.edu.cn, E-mail: qujl@ihep.ac.cn [Laboratory for Particle Astrophysics, CAS, Beijing 100049 (China)

    2017-06-01

    Using archival Rossi X-ray Timing Explorer ( RXTE ) data, we studied the low-frequency quasi-periodic oscillations (LFQPOs) in the neutron star low-mass X-ray binary (LMXB) Cir X-1 and examined their contribution to frequency–frequency correlations for Z sources. We also studied the orbital phase effects on the LFQPO properties and found them to be phase independent. Comparing LFQPO frequencies in different classes of LMXBs, we found that systems that show both Z and atoll states form a common track with atoll/BH sources in the so-called WK correlation, while persistent Z systems are offset by a factor of about two. We found that neither source luminosity nor mass accretion rate is related to the shift of persistent Z systems. We discuss the possibility of a misidentification of fundamental frequency for horizontal branch oscillations from persistent Z systems and interpreted the oscillations in terms of models based on relativistic precession.

  17. Causes of mortality in green turtles from Hawaii and the insular Pacific exclusive of fibropapillomatosis

    Science.gov (United States)

    Work, Thierry M.; Balazs, George H.; Summers, Tammy M.; Hapdei, Jessy R.; Tagarino, Alden P.

    2015-01-01

    Fibropapillomatosis (FP) comprises a majority of green turtle stranding in Hawaii; however, green turtles in the Pacific are also susceptible to non-FP related causes of death. We present here necropsy findings from 230 free-ranging green turtles originating from Hawaii, the Mariana archipelago, Palmyra Atoll, American Samoa, and Johnston Atoll that died from non-FP related causes. Most turtles died from fishing-induced or boat strike trauma followed by infectious/inflammatory diseases, nutritional problems (mainly cachexia), and an array of physiologic problems. Infectious/inflammatory problems included bacterial diseases of the lungs, eyes, liver or intestines, spirorchid fluke infection, or polyarthritis of unknown origin. Likelihood of a successful diagnosis of cause of death was a function of post-mortem decomposition. Fibropapillomatosis was not seen in turtles submitted from outside Hawaii. The preponderance of anthropogenic causes of mortality offers some management opportunities to mitigate causes of death in these animals by, for example, implementing measures to decrease boating and fishing interactions.

  18. The Kwajalein bioremediation demonstration: Final technical report

    International Nuclear Information System (INIS)

    Walker, J.R. Jr.; Walker, A.B.

    1994-12-01

    The US Army Kwajalein Atoll (USAKA) Base, located in the Republic of the Marshall Islands (RMI) in the east-central Pacific Ocean, has significant petroleum hydrocarbon contamination resulting from years of military activities. Because of its remoteness, the lack of on-site sophisticated remediation or waste disposal facilities, the amenability of petroleum hydrocarbons to biodegradation, and the year-round temperature favorable for microbial activity, USAKA requested, through the Hazardous Waste Remedial Actions Program (HAZWRAP), that a project be conducted to evaluate the feasibility of using bioremediation for environmental restoration of contaminated sites within the atoll. The project was conducted in four distinct phases: (1) initial site characterization and on-site biotreatability studies, (2) selection of the demonstration area and collection of soil columns, (3) laboratory column biotreatability studies, and (4) an on-site bioremediation demonstration. The results of phases (1) and (3) have been detailed in previous reports. This report summarizes the results of phases (1) and (3) and presents phases (2) and (4) in detail

  19. Comparative behavior of plutonium and americium in the equatorial Pacific

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Jokela, T.A.; Brunk, J.L.; Eagle, R.J.

    1983-01-01

    Inventories of 239 + 240 Pu and 241 Am greatly in excess of global fallout levels persist in the benthic environments of Bikini and Enewetak Atolls. The amount of 239 + 240 Pu mobilized to solution at the atolls can be predicted from a distribution coefficient K/sub d/ of 2.3 x 10 5 and the mean sediment concentrations. The mobilized 239 + 240 Pu has solute-like characteristics and different valence states coexist in solution - the largest fraction of the soluble plutonium is in an oxidized form (+V,VI). The adsorption of plutonium to sediments is not completely reversible because of changes that occur in the relative amounts of the mixed oxidation states in solution with time. Characteristics of 239 + 240 Pu described at one location may not necessarily describe its behavior elsewhere. The relative amounts of 241 Am to 239 + 240 Pu may be altered in future years because of mobilization and radiological decay

  20. Preliminary evaluation of the radiological quality of the water on Bikini and Eneu Islands

    International Nuclear Information System (INIS)

    Noshkin, V.E.; Wong, K.M.; Eagle, R.J.; Brown, G.

    1975-01-01

    In June of 1975 a survey was conducted to determine the residual radioactivity in the terrestrial environment on the two main islands (Eneu and Bikini) of Bikini Atoll. The objective was to evaluate the potential radiation doses that could be received by the Bikinians scheduled to return to their atoll. This report describes the radiological quality of the groundwater during June 1975 (from data obtained from water samples collected at old and new well sites on both islets) and the cistern water on Bikini island. Based on the analyses of these samples, the cistern water from Bikini Island is both chemically and radiologically acceptable as drinking water in accordance with standard limits established by the U. S. Public Health Service. On both islands the quality of the ground water varies from one site to another. At some wells both chemical and radiological quality are acceptable; at others one or both is unacceptable according to U. S. Public Health Standards

  1. Near-island biological hotspots in barren ocean basins.

    Science.gov (United States)

    Gove, Jamison M; McManus, Margaret A; Neuheimer, Anna B; Polovina, Jeffrey J; Drazen, Jeffrey C; Smith, Craig R; Merrifield, Mark A; Friedlander, Alan M; Ehses, Julia S; Young, Charles W; Dillon, Amanda K; Williams, Gareth J

    2016-02-16

    Phytoplankton production drives marine ecosystem trophic-structure and global fisheries yields. Phytoplankton biomass is particularly influential near coral reef islands and atolls that span the oligotrophic tropical oceans. The paradoxical enhancement in phytoplankton near an island-reef ecosystem--Island Mass Effect (IME)--was first documented 60 years ago, yet much remains unknown about the prevalence and drivers of this ecologically important phenomenon. Here we provide the first basin-scale investigation of IME. We show that IME is a near-ubiquitous feature among a majority (91%) of coral reef ecosystems surveyed, creating near-island 'hotspots' of phytoplankton biomass throughout the upper water column. Variations in IME strength are governed by geomorphic type (atoll vs island), bathymetric slope, reef area and local human impacts (for example, human-derived nutrient input). These ocean oases increase nearshore phytoplankton biomass by up to 86% over oceanic conditions, providing basal energetic resources to higher trophic levels that support subsistence-based human populations.

  2. Militarism Versus Development. Teaching Global Issues.

    Science.gov (United States)

    Gage, Susan

    1988-01-01

    Articles and activities written for the senior secondary level explore the complex links between militarization and underdevelopment. The articles discuss choices between missiles and food in developing countries, the internal and external causes of militarism, and the hidden costs of militarism. Case studies of the Kwajalein Atoll and Ethiopia…

  3. 76 FR 34967 - Endangered Species; File No. 10027

    Science.gov (United States)

    2011-06-15

    ... and related documents are available for review by selecting ``Records Open for Public Comment'' from... distribution and abundance, ecology, health, and threats to sea turtles at the Palmyra Atoll in the Pacific.... These data will help determine if temporal, stage-specific, or sex-specific movement patterns exist for...

  4. Hacktivism as a radical media practice

    NARCIS (Netherlands)

    Milan, S.; Atton, C.

    2015-01-01

    When in September 1995 President Jacques Chirac announced that France would run a series of nuclear tests in the Polynesian atoll of Mururoa, a group of Italian artists decided to exploit the technical properties of the nascent internet to make a political statement. The call for action invited

  5. Black reefs: iron-induced phase shifts on coral reefs

    NARCIS (Netherlands)

    Wegley Kelly, L.; Barott, K.L.; Dinsdale, E.; Friedlander, A.M.; Nosrat, B.; Obura, D.; Sala, E.; Sandin, S.A.; Smith, J.E.; Vermeij, M.J.A.; Williams, G.J.; Willner, D.; Rohwer, F.

    2012-01-01

    The Line Islands are calcium carbonate coral reef platforms located in iron-poor regions of the central Pacific. Natural terrestrial run-off of iron is non-existent and aerial deposition is extremely low. However, a number of ship groundings have occurred on these atolls. The reefs surrounding the

  6. Revisiting the Metaphor of the Island: Challenging "World Culture" from an Island Misunderstood

    Science.gov (United States)

    Rappleye, Jeremy

    2015-01-01

    This article revisits the newly "discovered" island that world culture theorists have repeatedly utilised to explain their theoretical stance, conceptual preferences and methodological approach. Yet, it seeks to (re)connect world culture with the real world by replacing their imagined atoll with a real one--the island-nation of Japan. In…

  7. Bibliography on Chernobyl radioactivity impacts and remediation of forest ecosystems

    Energy Technology Data Exchange (ETDEWEB)

    Rennie, C.D.; Baweja, A.S.

    1992-01-01

    Bibliography on the Chernobyl nuclear accident pertaining to radiological sources, distribution of radioactivity, transport of radionuclides in aquatic and terrestrial ecosystems, and biological impacts/indicators. The second section lists references on remediation technologies at Bikini Atoll Islands. References include books and periodicals from Canada, the United States, and European sources.

  8. African Journal of Marine Science - Vol 38, No 3 (2016)

    African Journals Online (AJOL)

    Protection of marine birds and turtles at St Brandon's Rock, Indian Ocean, requires conservation of the entire atoll · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. SW Evans, N Cole, H Kylin, NS Choong Kwet Yive, V Tatayah, J Merven, H Bouwman, 317-327.

  9. 50 CFR 38.9 - Breach of the peace.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Breach of the peace. 38.9 Section 38.9... peace. No person on Midway Atoll National Wildlife Refuge will: (a) With intent to cause public..., gestures, or displays, or address abusive language to any person present; or create a hazardous or...

  10. The Giant Tortoise Population of Aldabra (Cryptodira: Testudinidae ...

    African Journals Online (AJOL)

    The preliminary results of a study of the endemic giant tortoise population of Aldabra Atoll in the Indian Ocean (Geochelone gigatea Schweiger) are briefly described. Their number would appear to have increased dramatically since the turn of the century to their present level of some 141 000 individuals. Crude estimates of ...

  11. The potential of the coral species Porites astreoides as a paleoclimate archive for the Tropical South Atlantic Ocean

    DEFF Research Database (Denmark)

    Pereira, Natan S.; Sial, Alcides N.; Frei, Robert

    2017-01-01

    , Red Sea and Caribbean, but lack for the Equatorial South Atlantic. Here we present coral-based records of Sr/Ca, δ18O and δ13C and the first δ18O–SST calibration for the scleractinian coral species Porites astreoides from the Rocas Atoll, Equatorial South Atlantic. The investigated geochemical proxies...

  12. 50 CFR 38.11 - Prostitution and lewd behavior.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 6 2010-10-01 2010-10-01 false Prostitution and lewd behavior. 38.11... Prostitution and lewd behavior. No person on Midway Atoll National Wildlife Refuge will: (a) Engage in prostitution. “Prostitution” means the giving or receiving of the body for sexual intercourse for hire; or (b...

  13. Population studies of echinoderms and growth and mortality of sea cucumbers

    International Nuclear Information System (INIS)

    Ebert, T.A.

    1979-01-01

    Progress is reported on the following studies: methods of collecting sea cucumbers; determination of growth rates of plates of the calcareous ring; use of growth parameters and a length-frequency distribution to estimate mortality and population turnover; movement of materials through the atoll ecosystem; and autoradiographic studies on spines of sea urchins

  14. Fulltext PDF

    Indian Academy of Sciences (India)

    the Indo-Pacific and Atlantic (regions normally between the. Tropic of ... grow in shallow waters and border the coast closely or are separated from it ... lagoon. Atolls commonly occur in the Indo-Pacific, where they develop during slow subsidence of volcanic ... form coral reefs and forests similar to those in shallow waters in.

  15. 2010 Northwestern Hawaiian Islands Lidar - Midway Atoll

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Geological Survey (USGS) contracted with Hawaii-based Aerial Surveying, Inc. to collect lidar-derived elevation data over the low-lying areas within the...

  16. RAINDROP DISTRIBUTIONS AT MAJURO ATOLL, MARSHALL ISLANDS.

    Science.gov (United States)

    RAINDROPS, MARSHALL ISLANDS ), (*ATMOSPHERIC PRECIPITATION, TROPICAL REGIONS), PARTICLE SIZE, SAMPLING, TABLES(DATA), WATER, ATTENUATION, DISTRIBUTION, VOLUME, RADAR REFLECTIONS, RAINFALL, PHOTOGRAPHIC ANALYSIS, COMPUTERS

  17. 2010 Northwestern Hawaiian Islands Lidar - Kure Atoll

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The U.S. Geological Survey (USGS) contracted with Hawaii-based Aerial Surveying, Inc. to collect lidar-derived elevation data over the low-lying areas within the...

  18. Quantifying climatological ranges and anomalies for Pacific coral reef ecosystems.

    Science.gov (United States)

    Gove, Jamison M; Williams, Gareth J; McManus, Margaret A; Heron, Scott F; Sandin, Stuart A; Vetter, Oliver J; Foley, David G

    2013-01-01

    Coral reef ecosystems are exposed to a range of environmental forcings that vary on daily to decadal time scales and across spatial scales spanning from reefs to archipelagos. Environmental variability is a major determinant of reef ecosystem structure and function, including coral reef extent and growth rates, and the abundance, diversity, and morphology of reef organisms. Proper characterization of environmental forcings on coral reef ecosystems is critical if we are to understand the dynamics and implications of abiotic-biotic interactions on reef ecosystems. This study combines high-resolution bathymetric information with remotely sensed sea surface temperature, chlorophyll-a and irradiance data, and modeled wave data to quantify environmental forcings on coral reefs. We present a methodological approach to develop spatially constrained, island- and atoll-scale metrics that quantify climatological range limits and anomalous environmental forcings across U.S. Pacific coral reef ecosystems. Our results indicate considerable spatial heterogeneity in climatological ranges and anomalies across 41 islands and atolls, with emergent spatial patterns specific to each environmental forcing. For example, wave energy was greatest at northern latitudes and generally decreased with latitude. In contrast, chlorophyll-a was greatest at reef ecosystems proximate to the equator and northern-most locations, showing little synchrony with latitude. In addition, we find that the reef ecosystems with the highest chlorophyll-a concentrations; Jarvis, Howland, Baker, Palmyra and Kingman are each uninhabited and are characterized by high hard coral cover and large numbers of predatory fishes. Finally, we find that scaling environmental data to the spatial footprint of individual islands and atolls is more likely to capture local environmental forcings, as chlorophyll-a concentrations decreased at relatively short distances (>7 km) from 85% of our study locations. These metrics will help

  19. Reefs and islands of the Chagos Archipelago, Indian Ocean: why it is the world’s largest no-take marine protected area

    Science.gov (United States)

    SHEPPARD, C. R. C.; ATEWEBERHAN, M.; BOWEN, B. W.; CARR, P.; CHEN, C. A.; CLUBBE, C.; CRAIG, M. T.; EBINGHAUS, R.; EBLE, J.; FITZSIMMONS, N.; GAITHER, M. R.; GAN, C-H.; GOLLOCK, M.; GUZMAN, N.; GRAHAM, N. A. J.; HARRIS, A.; JONES, R.; KESHAVMURTHY, S.; KOLDEWEY, H.; LUNDIN, C. G.; MORTIMER, J. A.; OBURA, D.; PFEIFFER, M.; PRICE, A. R. G.; PURKIS, S.; RAINES, P.; READMAN, J. W.; RIEGL, B.; ROGERS, A.; SCHLEYER, M.; SEAWARD, M. R. D; SHEPPARD, A. L. S.; TAMELANDER, J.; TURNER, J. R.; VISRAM, S.; VOGLER, C.; VOGT, S.; WOLSCHKE, H.; YANG, J. M-C.; YANG, S-Y.; YESSON, C.

    2014-01-01

    The Chagos Archipelago was designated a no-take marine protected area (MPA) in 2010; it covers 550 000 km2, with more than 60 000 km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs.It contains 25–50% of the Indian Ocean reef area remaining in excellent condition, as well as the world’s largest contiguous undamaged reef area. It has suffered from warming episodes, but after the most severe mortality event of 1998, coral cover was restored after 10 years.Coral reef fishes are orders of magnitude more abundant than in other Indian Ocean locations, regardless of whether the latter are fished or protected.Coral diseases are extremely low, and no invasive marine species are known.Genetically, Chagos marine species are part of the Western Indian Ocean, and Chagos serves as a ‘stepping-stone’ in the ocean.The no-take MPA extends to the 200 nm boundary, and. includes 86 unfished seamounts and 243 deep knolls as well as encompassing important pelagic species.On the larger islands, native plants, coconut crabs, bird and turtle colonies were largely destroyed in plantation times, but several smaller islands are in relatively undamaged state.There are now 10 ‘important bird areas’, coconut crab density is high and numbers of green and hawksbill turtles are recovering.Diego Garcia atoll contains a military facility; this atoll contains one Ramsar site and several ‘strict nature reserves’. Pollutant monitoring shows it to be the least polluted inhabited atoll in the world. Today, strict environmental regulations are enforced.Shoreline erosion is significant in many places. Its economic cost in the inhabited part of Diego Garcia is very high, but all islands are vulnerable.Chagos is ideally situated for several monitoring programmes, and use is increasingly being made of the archipelago for this purpose. PMID:25505830

  20. An estimate by two methods of thyroid absorbed doses due to BRAVO fallout in several Northern Marshall Islands.

    Science.gov (United States)

    Musolino, S V; Greenhouse, N A; Hull, A P

    1997-10-01

    Estimates of the thyroid absorbed doses due to fallout originating from the 1 March 1954 BRAVO thermonuclear test on Bikini Atoll have been made for several inhabited locations in the Northern Marshall Islands. Rongelap, Utirik, Rongerik and Ailinginae Atolls were also inhabited on 1 March 1954, where retrospective thyroid absorbed doses have previously been reconstructed. The current estimates are based primarily on external exposure data, which were recorded shortly after each nuclear test in the Castle Series, and secondarily on soil concentrations of 137Cs in samples collected in 1978 and 1988, along with aerial monitoring done in 1978. The external exposures and 137Cs soil concentrations were representative of the atmospheric transport and deposition patterns of the entire Castle Series tests and show that the BRAVO test was the major contributor to fallout exposure during the Castle series and other test series which were carried out in the Marshall Islands. These data have been used as surrogates for fission product radioiodines and telluriums in order to estimate the range of thyroid absorbed doses that may have occurred throughout the Marshall Islands. Dosimetry based on these two sets of estimates agreed within a factor of 4 at the locations where BRAVO was the dominant contributor to the total exposure and deposition. Both methods indicate that thyroid absorbed doses in the range of 1 Gy (100 rad) may have been incurred in some of the northern locations, whereas the doses at southern locations did not significantly exceed levels comparable to those from worldwide fallout. The results of these estimates indicate that a systematic medical survey for thyroid disease should be conducted, and that a more definitive dose reconstruction should be made for all the populated atolls and islands in the Northern Marshall Islands beyond Rongelap, Utirik, Rongerik and Ailinginae, which were significantly contaminated by BRAVO fallout.