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71.
A multi-criteria approach to Great Barrier Reef catchment (Queensland, Australia) diffuse-source pollution problem 总被引:1,自引:0,他引:1
This paper presents a multi-criteria based tool for assessing the relative impact of diffuse-source pollution to the Great Barrier Reef (GBR) from the river basins draining into the GBR lagoon. The assessment integrates biophysical and ecological data of water quality and pollutant concentrations with socio-economic information pertaining to non-point source pollution and (potential) pollutant impact. The tool generates scores for each river basin against four criteria, thus profiling the basins and enabling prioritization of management alternatives between and within basins. The results support policy development for pollution control through community participation, scientific data integration and expert knowledge contributed by people from across the catchment. The results specifically provided support for the Reef Water Quality Protection Plan, released in October 2003. The aim of the plan is to provide a framework for reducing discharge of sediment, nutrient and other diffuse-source loads and (potential) impact of that discharge and for prioritising management actions both between and within river basins. 相似文献
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Within the Coastal Benthic Boundary Layer (CBBL) Program’s Key West Campaign, a series of complementary geophysical experiments
were undertaken in the Lower Florida Keys. The primary objective was the collection of data to assist in the physical characterization
of the sea-floor carbonate sediments. Digital subbottom profiler data collected along closely spaced lines were processed
to produce maps of sea-floor reflectivity strength and variance. These were subsequently used to help map the spatial distribution
of the Holocene sediment and to identify and delineate the outcropping Pleistocene limestones and Holocene patch reefs. Analysis
of a complementary data set, comprised of shear wave velocities collected with a bottom-towed sled, provided additional valuable
information on the physical characteristics of the soft silty sediments making up the surficial cover at the CBBL Program’s
experimental tower site. 相似文献
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75.
Emmanuel Fritsch Etienne Balan Nadia Régina Do Nascimento Thierry Allard Marion Bardy Guilherme Bueno Sylvie Derenne Adolpho José Melfi Georges Calas 《Comptes Rendus Geoscience》2011,343(2-3):188-198
This article reports major results from collaborative research between France and Brazil on soil and water systems, carried out in the Upper Amazon Basin. It reveals the weathering processes acting in the partly inundated, low elevation plateaus of the Basin, mostly covered by evergreen forest. Our findings are based on geochemical data and mineral spectroscopy that probe the crystal chemistry of Fe and Al in mineral phases (mainly kaolinite, Al- and Fe-(hydr)oxides) of tropical soils (laterites). These techniques reveal crystal alterations in mineral populations of different ages and changes of metal speciation associated with mineral or organic phases. These results provide an integrated model of soil formation and changes (from laterites to podzols) in distinct hydrological compartments of the Amazon landscapes and under altered water regimes. 相似文献
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本文用CN算法研究了辽宁省两个地震重点监视防御区的中强震前的强震发生概率增长时间,结果表明预测效果较好,有震报准率为90%,TIP预测警戒占时空率为30%左右,R值评分为0.6左右。在TIP预测的基础上,进一步用SIP方法分析这两个区域的空间背景发震概率的不均匀分布。综合应用TIP方法和SIP方法,对辽宁省及邻近地区进行了试验性地震预报。 相似文献
78.
Martine M. Savard Christian Bégin Joëlle Marion Michel Parent 《Geochimica et cosmochimica acta》2005,69(15):3723-3731
Atmospheric pollution effects on hydrogen fractionation in trees are demonstrated for the first time in this study. The δ2H ring-cellulose series obtained for black spruce trees at a site near a SO2-emitting smelter display short-term fluctuations superimposed on a first order −11‰ shift coincident with the onset of smelter operations. The isotopic depletion in trees exposed to various levels of SO2 diminish with increasing distance relative to the location of the smelter, and it is not detected at the most distant selected stand, 116 km downwind from the point source. Both the spatial and temporal isotopic trends likely result from the combined effects of leaf transpiration, biochemical processes and water uptake by the root system. The spatial and temporal trends of δ2H values are the reverse of the δ13C trends previously obtained for the same tree ring series. These coupled isotopic fractionations underline an important response of trees to pollution stresses likely generated by ambient atmospheric SO2 concentrations. The degradation of global air quality during the last 150 yr likely generated large scale modifications in the way terrestrial vegetation grows. In this respect, hydrogen dendrogeochemistry combined with other tracers such as C isotope ratios constitutes a new tool to evaluate the past behavior of forest ecosystems in terms of C uptake and acclimation to various types of atmospheric pollution. 相似文献
79.
Environmental conservation and the production of new territories: the example of French départements
Pech Pierre Dizière Sophie Gillet Anne-Gabrielle Mamder Julie Tichit Marion 《GeoJournal》2010,75(2):149-161
Very important initiatives have been taken and policies have been adopted in the European Union to protect areas of great importance for threatened species and habitats. Protected areas differ broadly in terms of category, natural conditions and administrative organisation, from international initiative such as Biosphere Reserves, European ones with Natura 2000 network until the institution of national and regional protected areas. In France, the administrative subdivisions known as “départements” were created with the French Revolution in the end of the eighteenth century; in 1985 an original and autonomous procedure to establish special protected areas, called “Sensitive Natural Spaces” (SNS) was devolved to them. The scope of this paper is to present an overview of these devolved powers which enable French départements to create protected areas and to levy a departmental tax on sensitive natural spaces (DTSNS). We statistically studied some parameters by multivariate methods in order to explain the choices of this policy by the départements. The huge variations in the way these powers are implemented prove the development of new environmental territories. 相似文献
80.
Inshore coral reefs adjacent to the wet tropics in North Queensland, Australia, are regularly exposed to flood plumes from coastal river systems. Changes in the nature of these plumes have been linked to the declining health of coral reefs in the region. The effect of flood plumes on the health of inshore corals was investigated by quantifying aspects of the demography of populations of corymbose and digitate Acropora at three groups of Island reefs along a gradient of exposure and decreasing water quality (High Island >Frankland's >Fitzroy). The size-structures of colonies, the rates of sexual recruitment, and the growth and survival of juveniles, all varied among the Island reefs. Juvenile and adult sized colonies were far more abundant at the Fitzroy Island reefs, than at the High or Frankland Island reefs that were more exposed to flood plumes. Additionally, there were up to eight times as many sexual recruits at the Fitzroy Island reefs, compared with the High Island reefs. However, the rates of growth and survival of the juvenile sized corals at the Fitzroy Island reefs were lower than at the more exposed reefs. The comparatively low abundance of adult corals at the exposed reefs is most likely due to their histories of disturbance from crown-of-thorns and coral bleaching, but the lack of subsequent recovery due to their low levels of larval recruitment. If a stock-recruitment relationship is typical for these groups of reefs, then the low rates of recruitment may be linked to the low density of adult colonies. Alternately, direct or indirect effects of chronic exposure to poor water quality may have resulted in less suitable substrata for larval settlement. We discuss these results and provide examples of how information about population structure and dynamics can be used in simple matrix models to quantify the current and future health of populations of corals under various scenarios. 相似文献