Further analysis of the effect of bioturbation by Nephrops norvegicus (L.) on the acoustic return of the RoxAnnTM seabed discrimination system     

Pinn  Eunice H.; Robertson  M. R. 《ICES Journal of Marine Science》2001,58(1):216-219

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Emergence of multi-stakeholder-driven cooperative research in the Northwest Atlantic: The case of the Northeast Consortium     

Troy W. Hartley  Robert A. Robertson 《Marine Policy》2006

The past 50 years in the Gulf of Maine and Georges Bank is marked by a growing divide between fishermen, scientists, and managers. This paper tracks the scientific, regulatory, social and political evolution of fisheries management in the Northwest Atlantic, culminating in a distrustful and adversarial climate, a convergence of diverse policy needs, and the emergence of a multi-stakeholder cooperative research program—the Northeast Consortium. The institutional structure and activities of the Northeast Consortium are presented and we conclude with a discussion of the role of cooperative research in building mutual understanding and respect, trust and scientific legitimacy.  相似文献   

A comparative study of contaminant levels in Long Island Sound     

Andrew Robertson  Bernard W. Gottholm  Donna D. Turgeon  Douglas A. Wolfe 《Estuaries and Coasts》1991,14(3):290-298

This paper uses results from the National Oceanic and Atmospheric Administration’s National Status and Trends Program (NS&T) to place the environmental quality of Long Island Sound in a broader perspective. It compares levels of contaminants in blue mussels from ten Long Island Sound sites and in sediments from seven Long Island Sound sites with concentrations in the same media at 87 and 221 other sites, respectively, where comparable samples were obtained. In sediments, the levels of both trace metals and organic contaminants tend to be relatively high for Long Island Sound sites. This is especially true for five of the twelve metals (silver, cadmium, copper, lead, and zinc) and for five of six categories of organic contaminants (total chlordane, low molecular weight polycyclic aromatic hydrocarbons (PAHs), high molecular weight PAHs, total polychlorinated biphenyls, and total dichlorodiphenyltrichloroethanes). In mussels, the organic contaminant categories exhibit relatively high levels, but this is not true for most of the metals. In fact, four of the metals—arsenic, mercury, selenium, and zinc—show evidence of relatively low levels in mussels from Long Island Sound compared to other NS&T locations.  相似文献   

Vulnerability assessment of coastal bridges on Oahu impacted by storm surge and waves     

Masoud Hayatdavoodi  R. Cengiz Ertekin  Ian N. Robertson  H. Ronald Riggs 《Natural Hazards》2015,79(2):1133-1157

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Spatio-temporal variability and predictability of summer monsoon onset over the Philippines     

V. Moron  A. Lucero  F. Hilario  B. Lyon  A. W. Robertson  D. DeWitt 《Climate Dynamics》2009,33(7-8):1159-1177

The spatio-temporal variability of boreal summer monsoon onset over the Philippines is studied through the analysis of daily rainfall data across a network of 76 gauges for the period 1977 to 2004 and the pentad Merged Analysis of Precipitation from the US Climate Prediction Center from 1979 to 2006. The onset date is defined using a local agronomic definition, namely the first wet day of a 5-day period receiving at least 40 mm without any 15-day dry spell receiving <5 mm in the 30 days following the start of that period. The onset is found to occur rather abruptly across the western Philippines around mid-May on average and is associated with the set-up of a “classical” monsoonal circulation with low-level easterlies subsequently veering to southerly, and then southwesterly. The onset manifests itself merely as a seasonal increase of rainfall over the eastern Philippines, where rainfall occurs throughout most of the year. Interannual variability of the onset date is shown to consist of a spatially coherent large-scale component, rather similar over the western and eastern Philippines, with a moderate to high amount of local-scale (i.e. station scale) noise. In consequence, the large-scale signal can be easily retrieved from any sample of at least 5–6 stations across the network although the local-scale coherence and fingerprint of the large-scale signal of the onset date are found to be stronger over the central Philippines, roughly from Southern Luzon to Northern Mindanao. The seasonal predictability of local onset is analyzed through a cross-validated canonical correlation analysis using tropical Pacific and Indian Ocean sea surface temperature in March and the 850 hPa May wind field from dynamical forecast models as predictors. The regional-scale onset, defined as the average of standardized local-scale anomalies in onset date, shows good predictive skill (r ≈ 0.8). Moreover, most of the stations show weak to moderate skill (median skill = 0.28–0.43 depending on the scheme) with spatial averaging across stations typically increasing skill to >0.6.  相似文献   

Gravitational attraction of local crustal masses in spherical coordinates     

D. A. Smith  D. S. Robertson  D. G. Milbert 《Journal of Geodesy》2001,74(11-12):783-795

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Spatial and temporal patterns of the infaunal community near a major ocean outfall in Southern California   总被引：1，自引：0，他引：1  

D. R. Diener  S. C. Fuller  A. Lissner  C. I. Haydock  D. Maurer  G. Robertson  T. Gerlinger 《Marine pollution bulletin》1995,30(12):861-878

Effects of waste water discharge from a major ocean outfall in Southern California to the benthic infaunal community were examined during a 5-year monitoring programme. Natural features, primarily water depth, accounted for 82% of the variability in the infaunal community, while discharge-related effects represented less than 8% of the variability. The area immediately adjacent to the diffuser had the strongest outfall effects. Infaunal abundance showed a pattern of enhancement centred at the outfall. Diversity was also high, indicating that the area was not characterized by a degraded community.  相似文献   

Major Ion and Trace Metal Geochemistry of an Acidic Septic-System Plume in Silt   总被引：2，自引：0，他引：2  

W. D. Robertson  D. W. Blowes 《Ground water》1995,33(2):275-283

Four years of detailed ground-water monitoring at a newly installed, seasonal-use, domestic septic system located on poorly buffered (CaCO₃ equivalent content ≤ 1.6 wt.%) lacustrine silt, has revealed the development of an acidic ground-water plume. Acid, generated by the partial oxidation of effluent NH₄⁺ dissolved organic carbon (DOC), and possibly sulfide minerals present in the sediment, has resulted in a distal plume core zone with pH values in the range of 4.4 to 5.0. The acidic zone, where NH₄⁺ does, however, persist (> 2 mg/1, as N) and where DOC remains elevated (6–13 mg/1), is associated with high average concentrations of the trace metals Fe (4.7 mg/1), Al (1.9 mg/1), and Mn (3.6 mg/1). Attenuation of nitrogen along the plume core flowpath is indicated by a decrease in the N/ Cl⁻ ratio from an effluent value of 1.7, to a plume value of only 0.5 after 4 m of subsurface flow. Increased SO₄²⁻ levels observed in the zone of N depletion suggest that attenuation can be at least partly attributed to reduction of plume NO₃⁻ by oxidation of reduced S present in the sediment. PO₄³⁻ has not migrated significantly beyond the infiltration bed gravel layer, demonstrating that PO₄³⁻ mobility is limited in these sediments (retardation factor > 10).  相似文献   

Palaeomagnetism of the monzonite porphyry from Milton,New South Wales     

William A. Robertson 《Pure and Applied Geophysics》1964,59(1):93-99

Summary Directions of natural remanent magnetization aftermagnetic cleaning of specimens from monzonite porphyry at Milton are given. Thermal and alternating magnetic field stability tests indicate that the resultant direction is that of the earth's magnetic field at the time of cooling. Comprison of the pole position calculated from this result with other pole positions from rocks of known age confirms the probable Permian age of the intrusion and the wide divergence of Australian from European and North American pole positions of this age.  相似文献   

Production and Transportation of Oil and Gas,A.P. Szilas (Ed.), Elsevier,Amsterdam (1975), p. 630, Dfl. 175.00     

John D. Robertson  George V. Chilingarian 《Engineering Geology》1976,10(1):80-81

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