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We report the development of a methodology for assessing confidence in ecological status classifications. The method presented here can be considered as a secondary assessment, supporting the primary assessment of eutrophication or ecological status. The confidence assessment is based on scoring the quality of the indicators on which the primary assessment is made. This represents a first step towards linking status classification with information regarding their accuracy and precision. Applied to an existing data set used for assessment of eutrophication status of the Baltic Sea (including the Kattegat and Danish Straits) we demonstrate that confidence in the assessment is Good or High in 149 out of 189 areas assessed (79%). Contrary to our expectations, assessments of the open parts of the Baltic Sea have a higher confidence than assessments of coastal waters. We also find that in open waters of the Baltic Sea, some biological indicators have a higher confidence than indicators representing physical-chemical conditions. In coastal waters, phytoplankton, submerged aquatic vegetation and indicators of physical-chemical conditions have a higher confidence than indicators of the quality of benthic invertebrate communities. Our analyses also show that the perceived weaknesses of eutrophication assessments are due more to Low confidence in reference conditions and acceptable deviations, rather than in the monitoring data. 相似文献
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The use of benthic indicators in Europe: from the Water Framework Directive to the Marine Strategy Framework Directive 总被引:1,自引:0,他引:1
Van Hoey G Borja A Birchenough S Buhl-Mortensen L Degraer S Fleischer D Kerckhof F Magni P Muxika I Reiss H Schröder A Zettler ML 《Marine pollution bulletin》2010,60(12):2187-2196
The Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD) are the European umbrella regulations for water systems. It is a challenge for the scientific community to translate the principles of these directives into realistic and accurate approaches. The aim of this paper, conducted by the Benthos Ecology Working Group of ICES, is to describe how the principles have been translated, which were the challenges and best way forward. We have tackled the following principles: the ecosystem-based approach, the development of benthic indicators, the definition of ‘pristine’ or sustainable conditions, the detection of pressures and the development of monitoring programs. We concluded that testing and integrating the different approaches was facilitated during the WFD process, which led to further insights and improvements, which the MSFD can rely upon. Expert involvement in the entire implementation process proved to be of vital importance. 相似文献
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Environmental indicators are being increasingly used to emphasise the relevance of monitoring. However, indicators must also be effective. In particular, they must be able to answer management questions, be accessible to the target audience and be sufficiently precise. Here, we use a time series of mercury levels in plaice from Liverpool Bay to illustrate how specific management questions can be formulated, answered, and the precision of these answers assessed. We also show how a programme design can incorporate a series of management questions that are likely to arise over time in response to observed changes in a time series. 相似文献
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为优化地下水水质监测方案,确定北京顺平岩溶水系统岩溶水水质的主要控制指标,快速掌握地下水水质变化,基于2022年顺平岩溶水系统49件岩溶水样品,综合运用统计分析、Piper三线图和熵权水质指数(entropy weight water quality index, EWQI)分析研究区水化学和水质特征,并耦合逐步多元线性回归分析,探讨能代表研究区岩溶水水质的关键指标。结果显示:(1)顺平岩溶水系统岩溶水具有微碱性、低盐度的特征,水化学类型主要为HCO-3—Ca2+·Mg2+型(7347%)。超标指标为 Nan(NH3或N+4中的N, 即氨氮以氮计)、pH值、Fe、Mn和F-,超标率分别为1020%、408%、408%、408%和204%。(2)研究区EWQI平均值为2633,水质“极好”,其中极好和良好所占比例分别为9184%和816%。(3)基于地下水水质数据构建的EWQImin模型筛选的关键指标为Nan、Fe、Mn、Nntr(硝氮以氮计, 硝酸盐中N)和F-,其决定系数(R2)和百分比误差(PE)分别为0986和388%。表明,EWQImin模型优选指标可以代表顺平岩溶水系统的水质状况,对优化水质监测网等水资源管理提供了参考价值。 相似文献