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Rapid underway profiling of water quality in Queensland estuaries   总被引:1,自引:0,他引:1  
We present an overview of a portable underway water quality monitoring system (RUM-Rapid Underway Monitoring), developed by integrating several off-the-shelf water quality instruments to provide rapid, comprehensive, and spatially referenced 'snapshots' of water quality conditions. We demonstrate the utility of the system from studies in the Northern Great Barrier Reef (Daintree River) and the Moreton Bay region. The Brisbane dataset highlights RUM's utility in characterising plumes as well as its ability to identify the smaller scale structure of large areas. RUM is shown to be particularly useful when measuring indicators with large small-scale variability such as turbidity and chlorophyll-a. Additionally, the Daintree dataset shows the ability to integrate other technologies, resulting in a more comprehensive analysis, whilst sampling offshore highlights some of the analytical issues required for sampling low concentration data. RUM is a low cost, highly flexible solution that can be modified for use in any water type, on most vessels and is only limited by the available monitoring technologies.  相似文献   

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Four watersheds, each characterized by a major resource use were selected for the study: The Vistula River in Poland—agriculture; the Dalälven River in Sweden—forestry; the Archipelago Sea in Sweden, Finland, Estonia—tourism; and the Lake Peipsi in Estonia/Russia—fisheries/agriculture. The main objective was to examine the reactions of particular ecosystems within the Baltic Sea drainage area, and to assess sustainability conditions on the regional level.The degree of sustainability and impact on the Baltic Sea were investigated through workshops and seminars in the areas. Overviews of environmental and socio-economic conditions were succinctly summarized in commissioned papers. Interventions by and discussions with scholars, sector experts, administrators and stakeholders of the various sites laid the foundation for conceptualizing the interaction of natural and human forces for each case. The project was able to draw quite a number of conclusions, summarized as the following lessons learnt.In the Vistula Region, nutrient emissions have levelled off but shortage of freshwater is critical. Forestry in the Dalälven watershed is largely environmental-friendly, except for fragmentation of the landscape and its negative impact on biodiversity. In the Archipelago area a former low-energy community has been replaced by a leisure time society. Different types of tourism is developing, but despite this variety, an improved integration of ecological properties with socio-economic patterns is required in order to build a sustainable, living Archipelago. The lake Peipsi basin and the surrounding area suffer both from problems of resource management and economic backwardness. Parts of the local economy has lost access to the one time large Soviet market, although the Estonian side has apparently benefited from present economic growth. To cope with the division of the lake, a regime for trans-national management is unfolding. It is based on both informal and, to an increasing extent, agreed professional contacts.Networks of engaged people were in all sites a resource for and promoter of the sustainability path. In order to succeed and to maintain the zeal, they need strong institutional support and common goals. Public programmes in the Baltic, ie. the work of the Helsinki Commission and Baltic Agenda 21, have developed instruments to enhance sustainability beneficial for the management of these watersheds. But critical tasks remain to be done in developing a shared understanding of ways to improve management of ecosystems with social factors.  相似文献   

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The major Proterozoic igneous intrusions in the Swedish sector of the Baltic Shield are the Ragunda complex (1293 m.y., palaeomagnetic pole 165°E, 54°N) and the Nordingrågabbro-granite-anorthosite complex (1385 ± 30 m.y.). The latter body has been partially remagnetised by later post-Jotnian dolerites (1254 m.y.), and sites influenced by the dolerites have a stable magnetisation with a mean direction D = 45°, I = ?39°, (α95 = 4.3°). Elsewhere, the gabbro-anorthosite facies have a magnetisation of dual polarity predating the dolerite and recoverable at various stages of thermal and/or a.f. cleaning with a mean of D = 48°, I = 37° (α95 = 5.3°); medium and high coercivity remanence resides in large magnetite grains and fine, predominantly hematite, rods in feldspar megacrysts. The Nordingrårapakivi granite yields a mean, also including dual polarities, of D = 221°, I = ?25° (α95 = 13°), and the Gävle granite yields a mean of D = 26°, I = 17° (α95 = 13°).New data define the a.p.w. path for the Baltic Shield after final uplift and cooling of the ca. 1800 m.y. Svecofennian mobile belt and prior to intrusion of the post-Jotnian dolerites at 1250 m.y.; this (ca. 1500–1200 m.y.) path defines a double loop similar in size and shape to the contemporaneous path for the Laurentian Shield and the paths can be superimposed to define relative positions of the shields. They were in juxtaposition prior to 1200 m.y. with the optimum reconstruction obtained by rotation of approximately 64° about a Euler pole at 1°E, 36°N. Pre-1500 m.y. palaeomagnetic data are also shown to fit this same unique reconstruction. The main geological correlations are an alignment of the Lower/Middle Proterozoic major strike-slip zones, the structural trends within the pre-1700 m.y. mobile belts, and the Grenville and Sveconorwegian (ca. 1100 m.y.) mobile belts. The anorogenic magmatism characteristic of Proterozoic times became gradually more restricted to one active margin of the continental reconstruction as temperature gradients decreased and the crust consolidated. All of these Proterozoic tectonic/magmatic trends are parallel to the long axis of the continental reconstruction.  相似文献   

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The results of studying tar balls on Baltic Sea beaches (the summer of 2008) are given with their comparison with other coastal areas. Tar balls in concentrations of 0.01–1.2 g/running m on the beaches of Sambiiskii Peninsula are found to correspond to a mean level of beach pollution. It is shown that, in addition to weathering, even high-molecular homologues in the composition of tar balls are rapidly decaying. Therefore, the molecular markers currently in use are not unequivocal indicators to the origin of hydrocarbons.  相似文献   

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Summary A recent informal attempt at Baltic inflow prediction is described. This forecast was based on the theory that the occurrence of major Baltic inflows is to a large extent determined by advection under the large-scale Atlantic windfield, rather than by purely local meteorological events over the Baltic itself. The forecast, completed in January 1972, proved to be successful, with the inflow beginning in April. Further tests of this simple technique of inflow prediction are planned.
Vorausberechnung größerer Zuflüsse zur Ostsee
Zusammenfassung Es wird ein kürzlich vorgenommener informeller Versuch beschrieben, größere Zuflüsse zur Ostsee vorauszusagen. Diese Voraussage basierte auf der Theorie, daß die Zuflüsse weitgehend bestimmt werden durch Advektion unter dem großräumigen atlantischen Windfeld, und nicht so sehr durch rein lokale meteorologische Ereignisse über der Ostsee selbst. Die im Januar 1972 fertiggestellte Voraussage erwies sich als richtig, denn im April begann ein erneuter Zufluß. Weitere Tests dieser einfachen Technik der Zufluß-Voraussage sind geplant.

La prédiction des principaux apports en Baltique
Résumé On décrit un essai de prévision des apports en Baltique fait récemment, d'une façon officieuse. Cette prédiction était basée sur la théorie suivant laquelle la venue des principaux apports en Baltique est, en grande partie, déterminée par l'advection à une grande échelle du champ des vents de l'Atlantique, plutôt que par la situation météorologique purement locale au-dessus de la Baltique elle-même. La prévision faite en janvier 1972 s'est révélée exacte pour l'apport commençant en avril. On projette de nouveaux essais de cette technique simple de prévision de l'apport.
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The monitoring programme of harmful substances in selected species in the Baltic Sea was started in 1979. In the present study, three-year averages of Zn, Cu, Cd and Pb in cod liver (Hg in cod muscle) and herring muscle are reported. The concentrations of heavy metals in cod show areal differences roughly in accordance with the concentrations of heavy metals in sea water. No significant differences between heavy metal concentrations in North Atlantic and Baltic Sea species were found, except for mercury, for which values in the Baltic Sea species are lower than in those from the North Atlantic.  相似文献   

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