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181.
182.
The Evolution of the Environmental Quality Concept: From the US EPA Red Book to the European Water Framework Directive 总被引:1,自引:0,他引:1
Vighi M Finizio A Villa S 《Environmental science and pollution research international》2006,13(1):9-14
- DOI: http://dx.doi.org/10.1065/espr2006.01.003
Background Water Quality Criteria were firstly defined in the 1970s by the EPA in the USA and the EIFAC in Europe, recognizing the need
for protecting water quality in order to allow the use of water resources by man. In the 1990s, the European Commission emphasized
the importance of safeguarding structure and function of biologic communities. These approaches were chemically-based. The
European Water Framework Directive (WFD) substantially changes the concept of Water Quality, by assuming that a water body
needs to be protected as an environmental good and not as a resource to be exploited. In this frame, the biological-ecological
quality assumes a prevailing role.
Main Features The Water Quality concept introduced by the WFD is a challenge for environmental sciences. Reference conditions should be
defined for different typologies of water bodies and for different European ecoregions. Suitable indicators should be developed
in order to quantify ecological status and to define what a 'good' ecological status is. Procedures should be developed for
correlating the deviation from a good ecological to the effects of multiple stressors on function and structure of the ecosystem.
The protection of biodiversity becomes a key objective. In this frame, the traditional procedures for ecotoxicological risk
assessment, mainly based on laboratory testing, should be overcome by more site-specific approaches, taking into account the
characteristics and the homeostatic capabilities of natural communities. In the paper an overview of the present knowledge
and of the new trends in ecotoxicology to get these objectives will be given. A procedure is suggested based on the concept
of Species Sensitivity Distribution (SSD).
Recommendations and Perspective . The need for more site-specific and ecologically-oriented approaches in ecotoxicology is strongly recommended. The development
of new tools for implementing the concept of 'Stress Ecology' has been recently proposed by van Straalen (2003). In the same
time, more 'cological realism'is needed in practically applicable procedures for regulatory purposes. 相似文献
183.
长江三角洲地区大气二恶英类污染物输送-沉降模拟研究 总被引:3,自引:1,他引:2
大气中的二恶英类物质(PCDD/Fs)是一类难降解的有毒污染物,可对人类和其他哺乳动物的健康构成危害.二恶英类物质主要是由废物焚烧、金属冶炼和造纸化工等行业所产生. 二恶英类物质为半挥发性物质,可以在气态和气溶胶之间相互转移,从而影响其大气物理和化学过程. 利用耦合有机物吸收和黑碳吸附的二恶英类污染物颗粒态、气态相间分配模块和化学转化的区域大气化学、输送模式(CMAQ)模拟了2006年1月,4月,7月和10月长三角(长江三角洲)地区PCDD/Fs在大气中的输送、转化和沉降等演变过程,探讨了大气中二恶英类污染物的季节变化规律和沉降特征. 模拟结果表明,长三角地区的二恶英类污染物排放存在着明显的长距离输送特征和区域影响;冬季大气二恶英类污染物浓度明显高于夏季,湿沉降是其主要的沉降途径. 相似文献
184.
Jason S. Link 《Ecological modelling》2010,221(12):1580-1591
The widespread use of ecological network models (e.g., Ecopath, Econetwrk, and related energy budget models) has been laudable for several reasons, chief of which is providing an easy-to-use set of modeling tools that can present an ecosystem context for improved understanding and management of living marine resources (LMR). Yet the ease-of-use of these models has led to two challenges. First, the veritable explosion of the use and application of these network models has resulted in recognition that the content and use of such models has spanned a range of quality. Second, as these models and their application have become more widespread, they are increasingly being used in a LMR management context. Thus review panels and other evaluators of these models would benefit from a set of rigorous and standard criteria from which the basis for all network models and related applications for any given system (i.e., the initial, static energy budget) can be evaluated. To this end, as one suggestion for improving network models in general, here I propose a series of pre-balance (PREBAL) diagnostics. These PREBAL diagnostics can be done, now, in simple spreadsheets before any balancing or tuning is executed. Examples of these PREBAL diagnostics include biomasses, biomass ratios, vital rates, vital rate ratios, total production, and total removals (and slopes thereof) across the taxa and trophic levels in any given energy budget. I assert that there are some general ecological and fishery principles that can be used in conjunction with PREBAL diagnostics to identify issues of model structure and data quality before balancing and dynamic applications are executed. I humbly present this PREBAL information as a simple yet general approach that could be easily implemented, could be considered for further incorporation into these model packages, and as such would ultimately result in a straightforward way to evaluate (and perhaps identify areas for improving) initial conditions in food web modeling efforts. 相似文献
185.
沉积物中多氯联苯分析的纯化条件优化研究 总被引:5,自引:3,他引:2
比较了各种填料层析柱和洗脱液的差别,并根据有机溶剂使用量较少的样品纯化方案,建立了适用低有机质含量水体表层沉积物中不同极性多氯联苯(PCBs)的分析方法.结果表明,该方法检测限在0.11 ng/g~0.35 ng/g(干重)之间,对主要多氯联苯同族体的回收率是77.9%~112.1%.用该法分析了长江中下游水体表层沉积物中的PCBs,质控结果表明,该纯化方法的效果理想. 相似文献
186.
187.
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189.
随着国家对生态环境的保护及管理力度不断加大,环境监测所发挥的作用也越来越凸显。但是在现有的技术条件下,结合我国各地区复杂的环境条件,使得环境监测的质量还是会受到多方面因素的影响。本次研究正是针对环境监测质量保证和质量控制因素及其对策进行分析,找到了影响环境监测质量的常见因素,并给出了控制优化环境监测质量的对策。 相似文献
190.
现在生态环境问题已经愈发明显,社会各界和政府都逐渐开始应用大量的生态技术来确保生态环境整体的稳定性。在这样的背景下,环境监测工作有了越来越重要的意义,如何在这一过程中确定技术应用方向并进一步进行有效的控制十分重要。 相似文献