A field study on the acute effects of the dispersant Corexit 9527 on glucose uptake by marine microorganisms     

R.P. Griffiths  T.M. McNamara  B.A. Caldwell  R.Y. Morita 《Marine environmental research》1981,5(2):83-91

The effects of the dispersant Corexit 9527 and Corexit with crude oil on the rate of glucose uptake and mineralisation were studied in Arctic and Subarctic marine waters and sediments. Essentially all of the 149 water and 95 sediment samples tested displayed decreased glucose uptake rates in the presence of either 15 or 50 ppm Corexit. Depressed uptake rates were observed at concentrations as low as 1 ppm. The mean concentration at which Corexit depressed glucose uptake by 50% was 12 ppm. The effect of Corexit was more pronounced on pelagic than on benthic microbial populations.  相似文献   

The invasive Asian green mussel Perna viridis in South Africa: all that is green is not viridis     

JM Micklem  CL Griffiths  N Ntuli  M Mwale 《African Journal of Marine Science》2016,38(2):207-215

The Asian green mussel Perna viridis is an invasive Indo-Pacific species recently reported from South African harbours. To verify the invasion, a phylogenetic (and morphological) analysis of green-shelled mussels (n = 39), found in six South African harbours, was conducted using the mitochondrial cytochrome c oxidase subunit I gene (COI). Estimates of genetic distances using the neighbour-joining analysis identified P. viridis only from Durban Harbour. All other green mussels were more than 3.2% divergent from P. viridis and were identified as green-shelled variants of indigenous P. perna. The only reliable morphological differences distinguishing the two species were the poorly developed mantle papillae and the wavy pallial line in P. viridis. The confirmed occurrence of P. viridis in a South African harbour suggests that there is a possible threat of the species becoming established and then spreading onto the open coast and competing with indigenous P. perna.  相似文献   

The stable isotopes of natural waters at the Marcell Experimental Forest     

Jonathan M. Stelling  Stephen D. Sebestyen  Natalie A. Griffiths  Carl P. J. Mitchell  Mark B. Green 《水文研究》2021,35(10):e14336

We present a new data set from the Marcell Experimental Forest (MEF) that compiles water isotope measurements from multiple research catchments, some of which have been studied since the 1960s. The MEF is located in northern Minnesota, USA, and is home to heavily studied and monitored forests, streams, bogs, and fens. Peat-forming systems (bogs and fens) are an important component of the MEF landscape and have a profound impact on the water cycle in these catchments. Within the last decade, analysis of stable isotopes of water (expressed as δD and δ¹⁸O) has been implemented to characterize the different components of the water budget, and to allow researchers to look at catchment and peatland-specific hydrologic effects in the watershed. This δD and δ¹⁸O data set of natural waters from MEF catchments is primarily composed of measurements from three peatlands (S1, S2, S6) during an 11-year period. More recently collection and analysis were expanded to also include samples from the Spruce and Peatland Responses Under Changing Environments (SPRUCE) project in the S1 bog, peatlands S3, S4, S5, as well as nearby lakes. We establish a local meteoric water line by analyzing the isotopic composition of precipitation, which fills a void in regional meteoric water lines for Minnesota. Furthermore, we establish baseline isotopic composition for bog outlet streams, bog porewater, aquifer groundwater, overland flow, subsurface stormflow, and snowpack, as well as runoff from the SPRUCE experimental chambers. These data are publicly available and will be expanded upon in the future.  相似文献   

Laboratory experiments on fronts     

R. W. Griffiths  P. F. Linden 《地球物理与天体物理流体动力学》2013,107(3-4):159-187

Abstract

Supercritically unstable density fronts near a vertical wall in a rotating, two-layer fluid were created on a laboratory turntable by withdrawing the outer wall of an annulus with a narrow gap, and allowing buoyant fluid from within the annulus to collapse toward a state of quasi-geostrophic balance. The resulting “coastal” current has a nearly uniform potential vorticity and is bounded by a front on which ageostrophic, wave-like disturbances grow. If the current width is comparable to the Rossby radius of deformation, the dominant length scale of disturbances is proportional to the width of the current. On the other hand, if the upper layer is much wider than the Rossby radius, then the observed length scale is a constant multiple of the Rossby radius. If the vertical boundary is omitted in the experiments, so that we are left with a circular anticyclonic vortex, the observed length scales and large-amplitude behaviour of disturbances are identical to those for the boundary currents, indicating that the wall has no significant influence on the flow.

At very large amplitude the growing waves lead to the formation of cyclone-anticyclone vortex pairs. For very wide currents, both the mean flow and the disturbances are first confined to a region within a few Rossby radii of the front. However, both the mean flow and the turbulent eddy motions slowly propagate into the previously stationary upper layer until, eventually, the whole of the upper layer is turbulent.  相似文献   

A numerical model comparison of baroclinic instability in the presence of topography     

Catherine Griffiths  Motoyoshi Ikeda  Peter C. Smith 《地球，A辑:动力气象学与海洋学》2000,52(1):42-65

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Firms and sustainability: Mapping the intellectual origins and structure of the corporate sustainability field     

Martina K. Linnenluecke  Andrew Griffiths 《Global Environmental Change》2013,23(1):382-391

Business research has repeatedly been criticized for its lack of engagement with pressing issues such as climate change, despite a surge of publications on corporate sustainability topics in recent years. We are therefore interested in identifying the knowledge development and knowledge gaps in business scholarship on the relationship between firms, environment and society. This paper provides a systematic review of the corporate sustainability field in form of a bibliometric analysis based on citation data acquired from the Social Sciences Citation Index. The final dataset contained 3117 records published between 1953 and 2011. Our analysis shows that, over the last 50 years, the field of corporate sustainability has emerged from a few primary nodes of research and developed into four distinct conceptual genealogies: corporate social performance theory, stakeholder theory, a corporate social performance versus economic performance debate, and a greening of management debate. The results of our analysis suggest four key findings. First, the four genealogies only comprise a relatively narrowly focused research scope. Second, there is very little integration and citation of work in other disciplinary areas such as ecology or environmental science. Third, the existing literature has a strong focus on empirically examining the relationship between a firm's environmental and/or social performance and its financial performance. Finally, there is little consideration of managerial implications and consequences of climate change in the corporate sustainability literature to date. We suggest that while this may be a reflection of an insular field, it may also be a role played by the management literature turning away from problem based issues in favor of empirical results, theory building, and the identification of variables that influence firm profitability and can be subjected to direct managerial control. We conclude by outlining pathways for future research.  相似文献   

Improving the assessment and valuation of climate change impacts for policy and regulatory analysis     

Alex L. Marten  Robert E. Kopp  Kate C. Shouse  Charles W. Griffiths  Elke L. Hodson  Elizabeth Kopits  Bryan K. Mignone  Chris Moore  Steve C. Newbold  Stephanie Waldhoff  Ann Wolverton 《Climatic change》2013,117(3):433-438

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Indigenous Livelihoods and Art Income: participation,production and returns from woodcarvings in Arnhem Land,north Australia     

Jennifer Koenig  Jon Altman  Anthony D. Griffiths 《The Australian geographer》2011,42(4):351-369

Participation in the Indigenous visual arts sector provides one of few market opportunities for Indigenous Australians resident on remote Aboriginal lands. In this article we examine the economic factors that influence this market engagement as they relate to woodcarving in the Maningrida region of Arnhem Land. In particular, we look at the factors that affect participation, production and monetary returns using scan and focal sampling, resource accounting and sales data from the regional art centre. Artists were engaged in a range of activities of which art production was the prominent means of productive cash income generation. An artist's residence and also their language community were found to influence the amount of sculpture production undertaken, with artists residing on ‘country’ in the hinterland being more engaged in sculpture production than those living in the township of Maningrida. The annual income earned by an artist for carving was highly variable and a large proportion of woodcarvers also earned income from producing artwork in other media. Capital costs were relatively minor, with travel costs and labour the main input into carving production. Based on the average return for a single woodcarving, $160, we estimate the average hourly return to artists as between $12 and $14. Whilst this figure is relatively low and comparable to the Australian award wage for unskilled labour, the income earned from arts production makes an important contribution to people's livelihoods.  相似文献   

Limitations of Current Approaches for Predicting Groundwater Vulnerability from PFAS Contamination in the Vadose Zone     

Matt Rovero  Diana Cutt  Rachel Griffiths  Urszula Filipowicz  Katherine Mishkin  Brad White  Sandra Goodrow  Richard T. Wilkin 《Ground Water Monitoring & Remediation》2021,41(4):62-75

Published literature for reported sorption coefficients (K_d) of eight anionic per- and polyfluoroalkyl substances (PFAS) in soil was reviewed. K_d values spanned three to five log units indicating that no single value would be appropriate for use in estimating PFAS impacts to groundwater using existing soil-water partition equations. Regression analysis was used to determine if the soil or solution parameters might be used to predict K_d values. None of the 15 experimental parameters collected could individually explain variability in reported K_d values. Significant associations between K_d and soil calcium and sodium content were found for many of the selected PFAS, suggesting that soil cation content may be critical to PFAS sorption, as previously noted in sources like Higgins and Luthy (2006), while organic carbon content was significant only at elevated levels (>5%). Unexplained discrepancies between the results from studies where PFAS were introduced to soil and desorbed in the laboratory and those that used material from PFAS-impacted sites suggest that laboratory experiments may be overlooking some aspects critical to PFAS sorption. Future studies would benefit from the development and use of standardized analytical methods to improve data quality and the establishment of soil parameters appropriate for collection to produce more complete data sets for predictive analysis.  相似文献   

Probabilistic infinite slope analysis   总被引：1，自引：0，他引：1  

D.V. Griffiths  Jinsong Huang  Gordon A. Fenton 《Computers and Geotechnics》2011

Research activity in the mechanics of landslides has led to renewed interest in the infinite slope equations, and the need for a more general framework for giving insight into the probability of failure of long slopes involving non-homogeneous vertical soil profiles and variable groundwater conditions. This paper describes a methodology in which parameters such as the soil strength, slope geometry and pore pressures, are generated using random field theory. Within the limitations of the infinite slope assumptions, the paper clearly demonstrates the important “seeking out” effect of failure mechanisms in spatially random materials, and how “first order” methods that may not properly account for spatial variability can lead to unconservative estimates of the probability of slope failure.  相似文献