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211.
212.
Peter E. Black 《Ground water》2005,43(6):778-778
213.
Comparison of Techniques for Visualising Fire Behaviour 总被引:1,自引:0,他引:1
Julian Black Colin Arrowsmith Michael Black William Cartwright 《Transactions in GIS》2007,11(4):621-635
During every Australian summer fires are common in the south‐eastern region of the continent. The combined forces of climate, topography and vegetation make Victoria in particular, one of the most fire prone regions on earth ( DSE 2003 ). Throughout its history, Victoria has seen a number of devastating bushfires, including Black Friday 1939, Ash Wednesday 1983, and more recently in the northeast of the State in 2003. The loss of life combined with the damage caused to land and property results in a heavy cost to the community. In Victoria, two of the organizations involved in fire management are the Victorian Department of Sustainability and Environment (DSE) and the Country Fire Authority (CFA). Both use fire ‘meters’ to determine potential fire behaviour given certain conditions. Values for temperature, wind speed, fuel load and vegetation type are input and a numerical estimate of fire danger given. There are a number of different meters used for different locations and environmental types. The most common meter used in Victoria is the McArthur Meter ( CSIR0 2001b ). The output data from this meter is numerical, and provides no spatial representation of fire danger. This paper looks at a variety of techniques used to visualise the numerical output from the McArthur Forest Fire Danger Meter. The article outlines the different models used by fire managers to simulate a fire situation, to assess future scenarios and for decision making involving fire management. Particular emphasis is placed on the McArthur Forest Fire Danger Meter as this is commonly used by fire departments in Australia. The article then focuses on geographical visualisation and a number of techniques employed to convey spatial information are discussed. The article then goes on to describe the fire simulation prototypes created for a study, a visualisation proof‐of‐concept product for organizations involved in managing bushfires in Australia. Finally, results from the evaluation of the prototype are presented. 相似文献
214.
Profitability of fish farming can be undermined by a suite of biological constraints. Effects of these constraints on the biology of the animal, the functioning of a tissue, or the quality of the final filleted product can be detected with very sensitive hi-tech approaches, grouped by the term ‘-omics’. These -omics technologies further present powerful tools for the genetic selection of diverse traits and, as such, will contribute substantially to the future development of the aquaculture sector. Sustainability issues of importance to the industry, such as environmental impacts, use of therapeutants, fish health management and fishmeal replacement, can again be aided, at least in part, through the effective use of -omics technologies. It thus appears that -omics technologies may be a key tool for the responsible growth of intensive aquaculture in the 21st century. In this paper we review the current status of -omics technologies and the potential for application within the aquaculture industry. 相似文献
215.
ABSTRACTThe 2011 wreck of the MV Rena off the northeast coast of New Zealand, and subsequent impacts, has been called New Zealand's worst ever maritime environmental disaster. It is certainly one of the world's most complex as it involved a pollutant combination of oil and dangerous goods debris in a dynamic oceanic environment adjacent to a pristine coastline. Heavy fuel oil, shipping containers loaded with cargo, and a wide range of wreck debris and contaminants were spread along hundreds of kilometres of coastline of the Bay of Plenty. Much of this landed on sandy beaches and rocky shores. Broken containers released often toxic substances, and the wreck itself slid down the pinnacle of the wreck site at Astrolabe Reef (Otaiti). The reef remains heavily contaminated, with substantial remnants of the ship and its cargo present, and chemical effects still evident in some species. Here we present the background and timeline of events that unfolded after the grounding. The following articles contain the results of the ensuing chemical, toxicological and ecological studies of contamination and environmental recovery. At the time of writing, numerous legacy issues remain. 相似文献
216.
Preliminary isotopic data for Late Proterozoic (~ 1100 Ma) granulite-facies metamorphics of the Prydz Bay coast indicate only very minor reworking (i.e., remetamorphism) of Archaean continental crustal rocks. Only two orthopyroxene—quartz—feldspar gneisses from the Rauer Group of islands, immediately adjacent to the Archaean Vestfold Block, show evidence for an Early Archaean origin (~ 3700—3800 Ma), whereas the vast majority of samples have Middle Proterozoic crustal formation ages (~ 1600–1800 Ma). The Prydz Bay rocks consist largely of garnet-bearing felsic gneisses and interlayered aluminous metasediments, although orthopyroxene-bearing gneisses are common in the Rauer Group; in contrast, Vestfold Block gneisses are predominantly orthopyroxene-bearing orthogneisses. The extensive Prydz Bay metasediments may have been derived by erosion of Middle Proterozoic rocks, such as the predominantly orthogneiss terrain of the Rauer Group, and deposited not long before the Late Proterozoic metamorphism. Data from nearby parts of the East Antarctic shield also suggest only limited Proterozoic reworking of the margins of the Archaean cratons.As in the Prydz Bay area, high-grade metamorphies in nearby parts of the East Antarctic shield show a secular increase in the sedimentary component. Archaean terrains like the Vestfold Block consist mainly of granitic orthogneisses derived by partial melting of igneous protoliths (I-type), whereas Late Proterozoic terrains (such as the Prydz Bay coast) include a much higher proportion of rocks derived either directly or by partial melting (S-type granitic orthogneisses) from sedimentary protoliths. Related chemical trends include increases in K2O2, Rb, Pb, and Th, and decreases in CaO, Na2O2 and Sr with decreasing age, essentially reflecting changes in the proportions of plagioclase and K-feldspar. 相似文献
217.
Philippa M. Black 《Contributions to Mineralogy and Petrology》1974,47(3):197-206
48 minerals from 18 in situ metamorphic rocks (mostly metasediments) from the Ouégoa district have been studied. Particular emphasis was placed on obtaining isotopic data for quartz, calcite and muscovite but some pyroxenes and amphiboles were also examined. Data for Ouégoa rocks show they have tended to be isotopically homogenized by metamorphism and that the effect of increasing metamorphism is to progressively deplete the rocks of heavy C and O isotopes. These results indicate that during metamorphism the rocks isotopically exchanged through the medium of a widespread oxygen-carrying fluid phase. Tentatively assigned temperatures obtained from isotopic data for quartz-calcite and quartz-muscovite pairs, using the calibration curves of Epstein and Taylor (1967), indicate lawsonite in the Ouégoa schists to be stable over a temperature range of 250 to 400° C and epidote from ca. 380° to at least 550° C. Temperatures for metamorphic zones in Ouégoa blueschists closely parallel those obtained for Type III and IV glaucophane-bearing rocks from Ward Creek, California (Taylor and Coleman, 1968). The measured tectonic thickness of lawsonite-bearing schists has been used to calculate a lithostatic pressure increment of 2 Kb and geothermal gradient of 20° C per km for the lawsonite zone. Comparison of lithostatic pressure increment with total pressure increment estimated from the stability relations of lawsonite over the temperature range 250–400° C (3.5 Kb Nitsch, 1972) suggest P total ≠ P lithostatic and that that the pressure of the fluid phase may have exceeded lithostatic pressure. 相似文献