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61.
Freshly excreted droppings from Canada geese (n=80), black swans (n=80), ducks (n=80) and gulls (n=80) were collected from sites around New Zealand. The droppings were enumerated for Escherichia coli, enterococci and Salmonella spp., and for the presence/absence of Cryptosporidium spp. Overall prevalence of E. coli and enterococci in samples was 95% and 94%, respectively. Cryptosporidium spp. was detected in 2% of the samples, whereas no Salmonella spp. were detected in the survey. Preliminary estimates of daily microbial outputs suggest that ducks will produce the highest loadings of E. coli and enterococci per bird, whereas Canada geese will produce the highest loadings of Campylobacter spp. per bird. This study provides the first set of indicator and pathogen counts for one of the largest sources of diffuse faecal contamination of natural waters in New Zealand. 相似文献
62.
Patrick S. Drupp Eric Heinen De Carlo Fred T. Mackenzie Christopher L. Sabine Richard A. Feely Kathryn E. Shamberger 《Aquatic Geochemistry》2013,19(5-6):371-397
An array of MAPCO2 buoys, CRIMP-2, Ala Wai, and Kilo Nalu, deployed in the coastal waters of Hawaii, have produced multi-year high temporal resolution CO2 records in three different coral reef environments off the island of Oahu, Hawaii. This study, which includes data from June 2008 to December 2011, is part of an integrated effort to understand the factors that influence the dynamics of CO2–carbonic acid system parameters in waters surrounding Pacific high-island coral reef ecosystems and subject to differing natural and anthropogenic stresses. The MAPCO2 buoys are located on the Kaneohe Bay backreef, and fringing reef sites on the south shore of Oahu, Hawaii. The buoys measure CO2 and O2 in seawater and in the atmosphere at 3-h intervals, as well as other physical and biogeochemical parameters (conductivity, temperature, depth, chlorophyll-a, and turbidity). The buoy records, combined with data from synoptic spatial sampling, have allowed us to examine the interplay between biological cycles of productivity/respiration and calcification/dissolution and biogeochemical and physical forcings on hourly to inter-annual time scales. Air–sea CO2 gas exchange was also calculated to determine whether the locations were sources or sinks of CO2 over seasonal, annual, and interannual time periods. Net annualized fluxes for CRIMP-2, Ala Wai, and Kilo Nalu over the entire study period were 1.15, 0.045, and ?0.0056 mol C m?2 year?1, respectively, where positive values indicate a source or a CO2 flux from the water to the atmosphere, and negative values indicate a sink or flux of CO2 from the atmosphere into the water. These values are of similar magnitude to previous estimates in Kaneohe Bay as well as those reported from other tropical reef environments. Total alkalinity (AT) was measured in conjunction with pCO2, and the carbonic acid system was calculated to compare with other reef systems and open ocean values around Hawaii. These findings emphasize the need for high-resolution data of multiple parameters when attempting to characterize the carbonic acid system in locations of highly variable physical, chemical, and biological parameters (e.g., coastal systems and reefs). 相似文献
63.
Chris Lutes Chase Holton Brian Schumacher John Zimmerman Andrew Kondash Robert Truesdale MS AB. 《Ground Water Monitoring & Remediation》2021,41(2):99-111
Temporal and spatial variability of indoor air volatile organic compound (VOC) concentrations can complicate vapor intrusion (VI) assessment and decision-making. Indicators and tracers (I&T) of VI, such as differential temperature, differential pressure, and indoor radon concentration, are low-cost lines of evidence to support sampling scheduling and interpretation of indoor air VOC sampling results. This study compares peak indoor air chlorinated VOC concentrations and I&T conditions before and during those peak events at five VI sites. The sites differ geographically and in their VI conceptual site models (CSM). Relative to site-specific baseline values, the results show that cold or falling outdoor temperatures, rising cross slab differential pressures, and increasing indoor radon concentrations can predict peak VOC concentrations. However, cold outdoor air temperature was not useful at one site where elevated shallow soil temperature was a better predictor. Correlations of peak VOC concentrations to elevated or rising barometric pressure and low wind speed were also observed with some exceptions. This study shows how the independent variables that control or predict peak indoor air VOC concentrations are specific to building types, climates, and VI CSMs. More I&T measurements at VI sites are needed to identify scenario-specific baseline and peak related I&T conditions to improve decision-making. 相似文献
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66.
Trace-metal pollution of soils in northern England 总被引:4,自引:0,他引:4
Data from a regional geochemical survey of topsoils (n=818) in rural and peri-urban areas over a single parent material (Coal Measures) are used to identify two types of trace-metal pollution - severe local contamination at 20 sites and widespread, diffuse pollution in more densely populated areas. Median concentrations of several trace metals in topsoils were significantly higher in areas of high, compared to low, population density (percentage increases in parenthesis): As (31), Cu (39), Fe (7), Mo (26-36), Ni (29), Pb (20), Sn (40), and Zn (11). Four potential pathways of diffuse trace-metal pollution are postulated: coal-ash dispersal, atmospheric aerosols derived from coal combustion, the historical spreading of sewage waste, and those related to road vehicles. The statistical analysis of geochemical data classified by local, human population density can be an effective means of identifying the magnitude and extent of diffuse pollution, and could help to establish natural background levels. 相似文献
67.
Chris E. Ostrander Margaret A. McManus Eric H. DeCarlo Fred T. Mackenzie 《Estuaries and Coasts》2008,31(1):192-203
While the physical forcing mechanisms that govern the outflows of major rivers throughout the world are well documented in the literature, comparably less research has been done to examine the mechanisms that govern the contributions of small rivers and streams to coastal ocean systems. These rivers and streams provide a direct means for the transport of anthropogenic and terrigenous materials from watersheds to coastal oceans. This study describes the temporal and spatial variability of freshwater plumes from Kaneohe Stream, Hawaii, USA, after storm events in the Kaneohe Bay watershed. Freshwater plumes were examined using a combination of fixed moorings, synoptic shipboard surveys, and lagrangian surface drifters. Data sets were collected over the course of 19 months from August 2005 to March 2007 with particular attention paid to storms during the boreal winters. Stream discharge and duration were found to exert a primary control on plume persistence in the southern Kaneohe Bay system. Time series data show a strong coherence between wind forcing and surface currents, which, in combination with data derived from shipboard and aerial surveys, indicate that the spatial variability of freshwater plumes is primarily determined by atmospheric forcing. 相似文献
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69.
Harmful algae and mariculture in New Zealand 总被引:3,自引:0,他引:3
Rhodes L. L.; Mackenzie A. L.; Kaspar H. F.; Todd K. E. 《ICES Journal of Marine Science》2001,58(2):398-403
70.
Chemical analyses of pore waters from recent marine carbonate sediments, Devil's Hole, Harrington Sound, Bermuda, have been obtained at intervals over a four year period. Interstitial waters were systematically analyzed for pH, titration alkalinity, dissolved sulfides, NH4+, Ca2+, Mg2+ and Na+ or Cl?. Additional analyses on some cores included SO42?, PO43?, dissolved CH4 and N2, and C:N:H ratios in the detrital organic material. The following general trends with depth (to ~ 1 m) are observed: (1) major cations show little or no change; (2) pH decreases; (3) alkalinity, sulfides, NH4+ and PO43? increase; (4) dissolved CH4 is consistently low. The chemical changes with depth can be modelled theoretically and are consistent with experimental data.Significant seasonal changes in pore water chemistry are observed. The data suggest an annual exchange between the pore waters (to a depth of ~ 1 m) and the overlying water of Harrington Sound; the exchange occurs between August and January. The nutrient flux out of the sediments during this process may be a major factor in the plankton ecology of Harrington Sound. 相似文献