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991.
Papastergiou P Mouchtouri VA Rachiotis G Pinaka O Katsiaflaka A Hadjichristodoulou C 《Marine pollution bulletin》2011,62(3):590-595
Our aim was to examine the health effects on bathers from exposure to recreational seawater on three beaches with different microbiology quality and bather density through a cohort study. An initial questionnaire and a 10 day follow up were used. Univariate and backward logistic regression analyses were used to asses the risk of developing symptoms or diseases among the bathers. In total, 3805 bathers were included in the study and 149 samples were collected from the three beaches. Despite all the beaches being characterized of high quality the levels of bacterial indicators differed among them. Health effects among bathers were not associated with bacterial indicators. A statistically significant increased risk for symptoms related to respiratory illness, gastroenteritis, medical consultation and use of medication was observed among bathers at the higher bather density beaches. Beach bather numbers should always be taken into account when considering a risk assessment approach. 相似文献
992.
Benthic faunal data is regularly collected worldwide to assess the ecological quality of marine environments. Recently, there has been renewed interest in developing biological indices able to identify environmental status and potential anthropogenic impacts. In this paper we evaluate the performance of a general polychaete/amphipod ratio along the Norwegian continental shelf as an environmental indicator for offshore oil and gas impacts. Two main trends are apparent: first, a contamination gradient is discernible from where production takes place compared to stations 10,000 m away. Second, the quality of the marine environment has improved over time. These results are consistent with monitoring reports employing a combination of uni- and multi-variate statistics. Thus, we consider this ratio as a relatively simple, useful and potentially cost-effective complement to other more demanding assessment techniques. Because of its strong theoretical basis, it may also be useful for detecting ecological change as a result of other activities. 相似文献
993.
Sánchez-Rodríguez A Sosa-Ferrera Z Santana-del Pino A Santana-Rodríguez JJ 《Marine pollution bulletin》2011,62(5):985-991
The presence of booster biocides in the aquatic environment has been associated with a risk to non-target species due to their proven toxicity. The aim of the present study was to determine the spatial and temporal distribution of common booster biocides in different harbours of the island of Gran Canaria (Spain) and evaluate, by means of a probabilistic risk assessment (PRA), the ecological risk posed by these compounds. With these objectives, a monitoring campaign was conducted between January 2008 and May 2009, collecting a total of 182 seawater samples. Four common booster biocides (TCMTB, diuron, Irgarol 1051 and dichlofluanid) were monitored. Diuron levels ranged between 2.3 and 203 ng/L and Irgarol 1051 between 2.4 and 146.5 ng/L. The ecological risk associated with these levels was always low, however, with probabilities of exceeding the 10th percentile of autotroph toxicity below 3.5%. 相似文献
994.
995.
西北太平洋热带气旋强度与环境气流切变关系的气候分析 总被引:5,自引:4,他引:1
采用NCEP/NCAR再分析资料和JTwC(美国关岛联合台风警报中心)资料,对1974~2004年5~10月西北太平洋热带气旋(TC)强度和环境风垂直切变进行了趋势特征、振荡周期和空间结构分析.结果表明:西北太平洋热带风暴强度以上TC的最大风速和环境风垂直切变在时间上有相反的变化趋势,弱的环境风垂直切变有利于TC强度的增大;前12 h的环境风垂直切变对TC强度的发展影响最大.环境风垂直切变在两北太平洋TC最强的年份表现为环境风切变值小,TC发生密集;最弱的年份表现为环境风切变值大,TC发生稀疏. 相似文献
996.
分析了温泉县历年来基本气候要素的变化,发现本地有着变暖、增湿、平均风速减小等变化趋势,结合对本地农牧业生产的影响提出一些启示。 相似文献
997.
A Survey of Techniques for Predicting Earthquake Ground Motions for Engineering Purposes 总被引:2,自引:0,他引:2
Over the past four or five decades many advances have been made in earthquake ground-motion prediction and a variety of procedures
have been proposed. Some of these procedures are based on explicit physical models of the earthquake source, travel-path and
recording site while others lack a strong physical basis and seek only to replicate observations. In addition, there are a
number of hybrid methods that seek to combine benefits of different approaches. The various techniques proposed have their
adherents and some of them are extensively used to estimate ground motions for engineering design purposes and in seismic
hazard research. These methods all have their own advantages and limitations that are not often discussed by their proponents.
The purposes of this article are to: summarise existing methods and the most important references, provide a family tree showing
the connections between different methods and, most importantly, to discuss the advantages and disadvantages of each method.
相似文献
John DouglasEmail: |
998.
Concern for natural hazard-triggered technological disasters (Natech disasters) in densely populated and industrialized areas
is growing. Residents living in urban areas subject to high natural hazard risk are often unaware of the potential for secondary
disasters such as hazardous materials releases from neighboring industrial facilities, chemical storage warehouses or other
establishments housing hazardous materials. Lessons from previous disasters, such as the Natech disaster during the Kocaeli
earthquake in Turkey in 1999 call for the need to manage low frequency/high consequence events, particularly in today’s densely
populated areas. However, there is little guidance available on how local governments and communities can assess Natech risk.
To add to the problem, local governments often do not have the human or economic resources or expertise to carry out detailed
risk assessments. In this article, we propose a methodology for preliminary assessment of Natech risk in urban areas. The
proposed methodology is intended for use by local government officials in consultation with the public. The methodology considers
possible interactions between the various systems in the urban environment: the physical infrastructure (e.g., industrial
plants, lifeline systems, critical facilities), the community (e.g., population exposed), the natural environment (e.g., delicate
ecosystems, river basins), and the risk and emergency management systems (e.g., structural and nonstructural measures). Factors
related to vulnerability and hazard are analyzed and qualitative measures are recommended. Data from hazardous materials releases
during the Kocaeli, Turkey earthquake of August 17, 1999 are used as a case study to demonstrate the applicability of the
methodology. Limitations of the proposed methodology are discussed as well as future research needs.
相似文献
Norio OkadaEmail: |
999.
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
1000.
As demands on aquatic resources increase, there is a growing need to monitor and assess their condition. This paper reviews a variety of aquatic environmental assessments, at local, national, international and global scales and finds confusion in the terminology used to describe assessments. In particular the terms 'ecosystem' and 'integrated' are often misused resulting in lack of clarity. Therefore, definitions of some assessment terminology are suggested, consolidating existing proposals and simplifying future applications. A conclusion from the review is that a new classification system is required. The categorisation system proposed builds on preliminary work of the International Council for the Exploration of the Sea (ICES). Assessment classification is based on the environmental components considered, methodologies and nature of the linkages between components, and the inclusion or exclusion of socio-economic factors. The assessment terminology and categorisation system provided could in future simplify the way that assessments are defined and used to inform development of management strategies. 相似文献