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21.
通过新旧生态环境影响评价导则HJ19-2011和HJ/T19-1997的对比分析,对两个导则中主要内容的差异进行了解析。以帮助读者了解新旧导则的异同,有利于更加深入地理解和使用新生态环境影响评价导则。 相似文献
22.
基于平衡分配法的太湖沉积物重金属质量基准及其在生态风险评价中的应用研究 总被引:3,自引:0,他引:3
水体沉积物评价和管理中最紧迫的问题是建立水体沉积物质量基准以保护水生生物.以太湖为研究对象,利用平衡分配法初步探讨了太湖不同湖区中Pb、Cu、Zn、Cr4种重金属的质量基准,分析了各校正项对不同重金属基准的贡献,利用基于沉积物质量基准的SQG-Q法对太湖各湖区沉积物重金属的潜在生态风险进行了评估.结果表明:SQGPb、SQGCu、SQGZn和SQGCr分别为21.2~307.4mg·kg-1、52.3~281.0mg·kg-1、399.7~1659.1mg·kg-1和21.2~68.7mg·kg-1,不同湖区沉积物重金属质量基准存在差异;SQGPb基本由AVS校正决定,Kp·WQC值和粒径校正两者主要决定了SQGCu和SQGZn,SQGCr则由Kp·WQC值、粒径校正、残渣态校正共同决定;四种重金属含量与沉积物质量基准初步值相比,超基准程度次序为Cr〉Pb〉Zn〉Cu;太湖各湖区沉积物中的重金属存在中等潜在生态风险,且大小顺序为竺山湾〉梅梁湾〉贡湖湾〉东太湖〉西部沿岸区和东部沿岸区〉湖心区〉南部沿岸区. 相似文献
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通过城镇化发展水平和发展效率两方面构建城镇化发展质量评价指标体系;采用熵权法确定指标权重,加权求和法综合评价江苏省城镇化发展质量并分析其城镇化发展水平、发展效率、发展质量的时空差异;依据各地市城镇化发展的不足开展新型城镇化建设分类导引。研究结果表明:近16a来江苏城镇化发展水平、发展效率和发展质量均不断提高,苏州、无锡、南京一直处于领先水平,从各地市城镇化发展水平的提高程度来看,表现出明显的快慢差异,苏南地区作为城镇化发展速度最快的地区,城镇化发展水平迅速提高,苏中地区受区位影响紧跟其后,但是对比城镇化发展效率看,城镇化发展水平与发展效率呈现不同步、不协调问题;经济城镇化和社会城镇化的主导因素是影响城镇化发展水平提高的主要驱动因素,城乡一体化的主导因素是影响城镇化发展效率提高的主要驱动因素;针对性解决影响其城镇化发展质量的主要"短板"问题是未来新型城镇化建设的必然途径。 相似文献
24.
Achim Lohmeyer Wolfgang Baechlin Matthias Ketzel 《Environmental monitoring and assessment》2000,65(1-2):381-387
The draft of the German guideline to calculate automobile exhaust dispersion is explained. It contains a two-stage-system: For first quick estimates the guideline contains the simple models MLuS and STREET. In case these models are not applicable or their results shows concentration levels close to the air quality standards, the more complex models PROKAS_V and MISKAM are recommended. PROKAS_V is a Gaussian plume model, MISKAM is a 3-dimensional microscale non hydrostatic flow model for built-up areas with an Eulerian dispersion model. The guideline comprises cases in rural areas without or with few adjacent buildings as well as urban areas with buildings near the roads. The contribution gives information about the models, typical results and some of the problems showing up presently. 相似文献
25.
In a fish testing strategy, positive results of the fish short term reproduction assay (FSTR), often trigger a definitive test like the fish sexual development test (FSDT) or the fish full life cycle test (FFLC), entailing ethical and economic problems. This study analysed 137 studies encompassing 35 chemicals with different modes of actions (MOAs). Variability is quantified for MOA endpoints vitellogenin (VTG) and secondary sex characteristics (SSCs) as well as for apical endpoints. Two MOA endpoints could indicate estrogenic, anti-estrogenic, androgenic, anti-androgenic and steroidogenesis activities. Great variability, however, has been observed for chemicals with anti-androgenic and steroidogenesis activities, suggesting that TG229/230 may not be sensitive enough to detect these types of chemicals and may produce false negatives. Changes in apical endpoints like fecundity are not limited to endocrine disrupting chemicals (EDCs). Non-EDCs could induce the similar effects on these apical endpoints. If elucidating MOA is needed, targeted in vitro MOA tests are suggested. Positive in vitro MOA results trigger a definitive test, which could be used for confirmation of the MOA in vivo and for deriving a no observed effect concentration (NOEC). Based on positive MOA results of TG229, a definitive test such as the FSDT or the FFLC is still needed, because the current TG229 has limitation on the derivation of a NOEC. An extended TG229 with more power to detect reproduction effects, as recently proposed in the OECD test guideline program, would improve the possibility to derive a NOEC and increase its usefulness in risk assessment. 相似文献
26.
Soil is the foundation of the entire biosphere. Knowledge of its heavy metal content and regional variability is essential to assess the environmental quality of soil and the extent of any contamination. In this study, 250 soil samples (within 125 soil profiles) were collected in undisturbed soils of the La Rioja region (an ideal place of the humid Mediterranean environment of Spain). The ‘total and bioavailable’ contents of copper (Cu) and zinc (Zn) were measured and their spatial variability assessed. The results indicate that Zn and Cu values were found to be very close to national and global averages. The spatial distribution of those elements was related to the nature of the bedrock and, to a lesser extent, was of anthropogenic origin. The variation of vertical distributions can be related, firstly, to natural sources – mainly the bedrock – and, secondly, to soil processes. From an ecological perspective, the ecosystem has not been affected by pollution. 相似文献
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Yamada Kazuhito Fujimori Mariko 《Mitigation and Adaptation Strategies for Global Change》2003,8(3):221-235
The success of CDM depends on active participation of public and private entities. In particular, participation of wide range
of private companies is an important factor for the success. In order to promote the participation of private companies in
the CDM project activities as project participants, the authors clarify the steps and technical issues involved in the CDM
project design procedures in a step-by-step approach. The steps consist of outlining the project plans, identifying project
impacts, defining a project boundary, estimating GHG emissions reduction/enhancement of removals, documenting the results
of estimation, and designing of monitoring plans. The authors also propose guidance for project participants, especially for
those not familiar with the CDM, which provides plain explanation of major technical issues. In order to further develop a
complete guideline, it is necessary to integrate the outputs of the ongoing international initiatives concerning technical
issues of CDM into the stepwise approach proposed in this paper.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Obiri-Danso Kwasi Jones Keith Jones Keith Paul Nigel 《Journal of Coastal Conservation》1999,5(1):51-58
The ability of Morecambe’s three designated bathing waters to pass the EU Directive on Bathing Water Quality depends on the
time of day when the sample is taken, the indicator organism tested for and whether the test uses the most strict (Guideline)
or the least strict (Imperative) criteria. Morning and afternoon sampling for faecal coliforms, faecal streptococci and the
pathogenCampylobacter was carried out monthly over the 1996 and 1997 bathing seasons. In the afternoons average faecal coliforms declined by 77%
in 1996 and 87% in 1997 compared with the mornings, faecal streptococci by 79% and 83% and campylobacters by 66% and 86%.
This decline in bacterial numbers between morning and afternoon was related to variations in water temperature and levels
of ultraviolet radiation. All three bathing waters failed the Guideline criteria of the EU Directive on Bathing Water Quality.
Using the Imperative criteria, no bathing waters passed in the mornings of either year, some passed in the afternoons of 1996
and all passed in the afternoons of 1997. The increased pass rate in 1997 coincided with improved sewage treatment, high temperatures
and increased levels of sunshine. In 1997 sampling by the Environment Agency produced fewer failures than our morning sampling
but more than our afternoon sampling. Their sampling was done around midday. It is suggested that where possible all sampling
of EU designated bathing waters should be carried out in the early morning. 相似文献