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Overview of integrative tools and methods in assessing ecological integrity in estuarine and coastal systems worldwide 总被引：9，自引：1，他引：8
Borja A Bricker SB Dauer DM Demetriades NT Ferreira JG Forbes AT Hutchings P Jia X Kenchington R Carlos Marques J Zhu C 《Marine pollution bulletin》2008,56(9):1519-1537
In recent years, several sets of legislation worldwide (Oceans Act in USA, Australia or Canada; Water Framework Directive or Marine Strategy in Europe, National Water Act in South Africa, etc.) have been developed in order to address ecological quality or integrity, within estuarine and coastal systems. Most such legislation seeks to define quality in an integrative way, by using several biological elements, together with physico-chemical and pollution elements. Such an approach allows assessment of ecological status at the ecosystem level ('ecosystem approach' or 'holistic approach' methodologies), rather than at species level (e.g. mussel biomonitoring or Mussel Watch) or just at chemical level (i.e. quality objectives) alone. Increasing attention has been paid to the development of tools for different physico-chemical or biological (phytoplankton, zooplankton, benthos, algae, phanerogams, fishes) elements of the ecosystems. However, few methodologies integrate all the elements into a single evaluation of a water body. The need for such integrative tools to assess ecosystem quality is very important, both from a scientific and stakeholder point of view. Politicians and managers need information from simple and pragmatic, but scientifically sound methodologies, in order to show to society the evolution of a zone (estuary, coastal area, etc.), taking into account human pressures or recovery processes. These approaches include: (i) multidisciplinarity, inherent in the teams involved in their implementation; (ii) integration of biotic and abiotic factors; (iii) accurate and validated methods in determining ecological integrity; and (iv) adequate indicators to follow the evolution of the monitored ecosystems. While some countries increasingly use the establishment of marine parks to conserve marine biodiversity and ecological integrity, there is awareness (e.g. in Australia) that conservation and management of marine ecosystems cannot be restricted to Marine Protected Areas but must include areas outside such reserves. This contribution reviews the current situation of integrative ecological assessment worldwide, by presenting several examples from each of the continents: Africa, Asia, Australia, Europe and North America. 相似文献
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Ground water bodies are important resources for drinking water, including bottled water, and national regulatory bodies should assess their quality continuously. For this purpose, an effective assessment system of bottled water at source should be installed. A hierarchical nested balance design for the collection of random primary duplicate water samples, and their replicate analyses, is described, and the use of robust analysis of variance to estimate measurement uncertainty. The latter is subsequently used for the development of four probabilistic categories for the classification of element concentrations in bottled water with respect to legislative standard values, i.e., (a) compliant (below Lower Threshold Limit), (b) possibly non-compliant (possibly above Standard Value), (c) probably non-compliant (probably above Standard Value), and (d) non-compliant (above Upper Threshold Limit), for the reliable assessment of compliance to European Union and national drinking water standards. Overall, the quality of European bottled water is considered good, with the exception of a few that have concentrations in Mn, B, Ba, As, Fe, Ni, Se, and Al, which are definitely above the estimated respective Upper Threshold Limit and, thus, exceed the corresponding legislative standard value defined by European Union directives. National regulatory bodies should verify these results, and install an efficient assessment system of compliance to regulatory limits using the methodology described in this paper. 相似文献
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Nikolai Dotzek Robert M. Rabin Lawrence D. Carey Donald R. MacGorman Tracy L. McCormick Nicholas W. Demetriades Martin J. Murphy Ronald L. Holle 《Atmospheric Research》2005,76(1-4):127
A multi-sensor study of the leading-line, trailing-stratiform (LLTS) mesoscale convective system (MCS) that developed over Texas in the afternoon of 7 April 2002 is presented. The analysis relies mainly on operationally available data sources such as GOES East satellite imagery, WSR-88D radar data and NLDN cloud-to-ground flash data. In addition, total lightning information in three dimensions from the LDAR II network in the Dallas–Ft. Worth region is used.GOES East satellite imagery revealed several ring-like cloud top structures with a diameter of about 100 km during MCS formation. The Throckmorton tornadic supercell, which had formed just ahead of the developing linear MCS, was characterized by a high CG+ percentage below a V-shaped cloud top overshoot north of the tornado swath. There were indications of the presence of a tilted electrical dipole in this storm. Also this supercell had low average CG− first stroke currents and flash multiplicities. Interestingly, especially the average CG+ flash multiplicity in the Throckmorton storm showed oscillations with an estimated period of about 15 min.Later on, in the mature LLTS MCS, the radar versus lightning activity comparison revealed two dominant discharge regions at the back of the convective leading edge and a gentle descent of the upper intracloud lightning region into the trailing stratiform region, apparently coupled to hydrometeor sedimentation. There was evidence for an inverted dipole in the stratiform region of the LLTS MCS, and CG+ flashes from the stratiform region had high first return stroke peak currents. 相似文献
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Manfred Birke Clemens Reimann Alecos Demetriades Uwe Rauch Hans Lorenz Bodo Harazim Wolfgang Glatte 《Journal of Geochemical Exploration》2010
A total of 1785 European bottled water samples were analyzed using standard laboratory methods. The bottled water samples were purchased in 2008 at supermarkets throughout 40 European countries. The samples were analyzed for 71 chemical parameters (As, Al, As, B, Ba, Be, Bi, Ca, Cd, Ce, Co, Cr, Cs, Cu, Dy, Er, Eu, Fe, Ga, Gd, Ge, Hf, Hg, Ho, I, K, La, Li, Lu, Mg, Mn, Mo, Na, Nb, Nd, Ni, Pb, Pr, Rb, Sb, Sc, Se, Sm, Sn, Sr, Ta, Tb, Te, Th, Ti, Tl, Tm, U, V, W, Y, Yb, Zn, Zr, Br−, HCO3−, Cl−, F−, NH4+, NO2−, NO3−, PO43−, SO42−, SiO2, pH, and EC) by quadrupole inductively coupled emission spectroscopy (ICP-QMS, trace elements), inductively coupled plasma atomic emission spectroscopy (ICP-AES, major elements), ion chromatography (IC, anions), atomic fluorescence spectrometry (AFS, Hg), titration (alkalinity), photometric methods (NH4+), potentiometric methods (pH), and conductometric methods (specific electrical conductivity, EC). A very strict quality control procedure was followed by analysing blanks, international reference materials, an internal project standard, and duplicate analyses, as well as by analysing 23 elements by both ICP-QMS and ICP-AES. Analysis of marketed bottled water from springs, wells or boreholes, apart from the evaluation of its quality with respect to inorganic elements, it may provide a cheap alternative to obtain a first impression about groundwater chemistry at the European scale. 相似文献
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Reproducibility of overbank sediment sampling was tested in twenty-nine floodplains in Europe, ten in Greece and nineteen in Norway, by the collection of duplicate pairs of samples. Distances between duplicate sites in Greece were 60 to 100 m, and in Norway 100 to 200 m. In Norway the same nineteen floodplains were sampled by a second team for the purpose of investigating differences in sampling variability and technique. Total element contents were determined in all samples. Paired samples were compared by calculating Spearman's rank correlation coefficient on the raw analytical data, and one-way analysis of variance on the log-transformed data. Pairs of overbank sediment samples collected from different floodplains by the Hellenic team and the first Norwegian team showed high rank correlations and low within-basin variability (sampling and analytical variance). Statistical results of the second Norwegian team were comparatively poorer; both Spearman's rank correlation coefficient and one-way analysis of variance, showed very low positive to negative correlations and high within-basin variation, suggesting a non-uniform distribution of elements in the Norwegian overbank sediment sequences and differences in the sampling technique of the two teams. Nevertheless, careful location of sample sites, as has been done by the Hellenic and the first Norwegian teams, reduces considerably the sampling variability, and the overall sampling reproducibility for most elements is very good for distances up to 100 m in Greece and 200 m in Norway, provided correlated overbank sediment sequences are sampled. The implication of this study for multinational regional geochemical mapping is that overbank sediment sampling must be carried out by well-trained professional teams of exploration geochemists, and where possible by one sampling team for the whole country. 相似文献
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Sixty-one still bottled water samples, representing 41 locations, were collected from Hellas for the purpose of studying the geochemistry of ground water. Since, the dominating lithology comprises limestone, dolomitic limestone, marble, and mafic–ultramafic rocks (ophiolites), the dominant major ions in Hellenic bottled waters are Ca2+, Mg2+, CO32− and HCO3−, and are, thus, classified in the Ca2+–Mg2+–HCO3− hydrochemical facies. The source aquifers of Hellenic bottled water are apparently continuously replenished by fresh water. Comparison of values of Ca, Mg, K, Na, Cl−, HCO3−, NO3−, SO42−, pH and electrical conductivity, displayed on bottle labels with those of this study, has shown that there is a fairly good correlation between the two data sets, suggesting that the geochemistry of source aquifers is relatively stable over time, at least from 1998 to 2008. 相似文献
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