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181.
为了推进环境治理体系建设和实现治理能力现代化,加大全国水环境保护工作开展的力度,国务院颁布了水污染防治纲领性文件《水污染防治行动计划》,其中第六条"严格环境执法监管"第十八款"加大执法力度"以十八届四中全会提出的"依法治国"及新《环保法》为基础,针对环境监管、加强执法等提出排污企业的"红黄牌"管理制度、逐级环境监督执法机制建设及严厉打击环境违法行为等具体措施,以铁腕治污,推进环境执法力度,全面打响水污染防治"攻坚战"。  相似文献   
182.
《水污染防治行动计划》提出要全面推行排污许可制度。文章指出法律约束力不强、制度定位不明确、许可量核定方法不统一是现行排污许可制度未发挥效用的主要原因,进而对许可条件、许可内容、许可量核定等关键问题进行了分析。根据前述分析,文章提出推进排污许可制度改革的建议,应当构建基于排污许可的点源污染管理体系,以排放量核算为重点,结合总量控制制度、排污权交易制度,强调落实排污单位主体责任,严格执法与处罚。  相似文献   
183.
根据2008年广西近岸海域入海污染源的监测调查结果,找出污染物的主要特征。结果表明,广西近岸海域入海污染物以有机物和营养盐为主,入海河流携带的有机物和营养盐占绝大部分,其次是市政混合排污口及海水养殖向近岸海域排放了较多有机物及营养盐。  相似文献   
184.
污染物的危害程度不仅与超标率和超标倍数有关,而且与污染物超标持续时间有关。同样高的污染物浓度,如果其持续时间长短不同,其对环境的生态效应是不同的。为此,在充分分析超标率、超标倍数所存在缺陷的基础上,通过实例分析对比,以直观图解的方式提出了一套新的污染物环境危害评价指标体系——超标强度指标体系。超标强度指标体系中涉及的主要概念和指标有标准面积、超标面积、超标持续时间、超标强度和综合超标强度。在阐述了各指标的概念含义和计算方法后,以同一组监测数据为例,用超标率和超标倍数与超标强度指标进行了对比评价。结果表明,用超标强度及其指标体系可以科学、准确区分和评判超标率、超标倍数指标体系所不能区分和评判的真实存在的客观事实,而且非常精确地给出了污染物超标持续时间。超标强度指标所涵盖的内容比超标率和超标倍数更丰富,评价的结果更准确,所反映的生态环境质量状况更客观准确、科学真实。超标持续时间表明了污染物超标状态的持续时间。  相似文献   
185.
The analysis aims to evaluate which is the most important among traffic parameters (flows, queues length, occupancy degree, and travel time) to forecast CO and C6H6 concentrations. The study area was identified by Notarbartolo Road and bounded by Libertà Street and Sciuti Street in the urban area of Palermo in Southern Italy. In this area, various loop detectors and one pollution-monitoring site were located. Traffic data related to the pollution-monitoring site immediately near the road link were estimated by Simulation of Urban MObility (SUMO) traffic microsimulator software using as input the flows measured by loop detectors on other links of road network. Traffic and weather data were used as input variables to predict pollutant concentrations by using neural networks. Finally, after a sensitivity analysis, it was showed that queues length were the mostly correlated traffic parameters to pollutant concentrations. An erratum to this article can be found at  相似文献   
186.
The physicochemical characteristics of the recipient environment into which chemical contaminants are deposited may influence their chemical speciation, mobility, bioavailability, and toxicity. In formulating Water Quality Criteria, the Environmental Protection Agency of the United States (EPA) considered the modifying effect of abiotic environmental factors on pollutant toxicity in an innovative regulatory approach. Scientific knowledge of the interactions and correlations between pollutant toxicity and abiotic factors remains limited. Recognition of the influence of the physicochemical characteristics of the recipient environment on pollutant toxicity has implications for the eventual formulation of regional, rather than uniform and national, criteria. In addition, in developing Water Quality Criteria that incorporate the effects of pollutants on aquatic life, EPA primarily focused on toxicity to aquatic animals and plants (including unicellular algae). The effects of pollutants on microbe-mediated ecological processes that are necessary for maintaining the state and quality of the ecosphere (such as biogeochemical cyclings, litter decomposition, and mineralization) were not included in the formulation of the Water Quality Criteria. To facilitate the recognition and quantification of adverse effects of pollutants on these ecological processes, the development of a computation, termed the ecological dosage 50% (EcD50) is recommended. Such a formulation could also be applied to setting environmental quality criteria for terrestrial ecosystems.  相似文献   
187.
重点污染源污染物排放总量监测管理信息系统   总被引:3,自引:0,他引:3       下载免费PDF全文
“江苏重点污染源污染物排放总量监测管理信息系统”软件是以全省重点污染源年排放申报登记数据和江苏省环境水系的编码成果作为系统设计的基础。该系统的功能框架设计是在征求了环境监测管理部门使用意见后逐步形成的,系统设计采用分模块平行开发方式,以微软新一代先进的开发平台,NET作为开发环境,用Access数据库管理软件存储全省总量监测数据。该系统具有对重点污染源废水,废气污染物监测的收集,汇总,分析,查询和报表打印等功能。  相似文献   
188.
The aluminum ions generated from mining aluminum,electrolytic aluminum and the industrial production of aluminum-based coagulants(such as AlCl_3 and Al_2(SO_4)_3) enter sewage treatment plants and interact with activated sludges.An anaerobic/anoxic/oxic(A~2 O) process was used to reveal the effects of Al~(3+) on the pollutant removal efficiencies,bioflocculation and the micro structure of sludge.The results showed that a low concentration of Al~(3+) improved the pollutant removal efficiencies and increased the sludge particle size.However,a high concentration of Al~(3+) hindered microbial flocculation and reduced the pollutant removal efficiencies.With a 10 mg/L Al~(3+) addition,the chemical oxygen demand(COD),total nitrogen(TN) and NH_4~+-N increased by 3%,16% and 27%,and reached as high as 68%,60% and 87%,respectively.At the same time,the dehydrogenase activity,flocculation ability(FA) and contact angle of the sludge reached their maximum levels at 41.3 mg/L/hr,45% and 79.63°,respectively.The specific surface area of the sludge decreased to 7.084 m2/g and the sludge pore size distribution shifted to concentrate in the me soporous range.Most of Al~(3+) was adsorbed on the surface of sludge,changing the physicochemical properties and physical structure of the sludge.  相似文献   
189.
高效藻类氧化塘处理有机废水的研究和应用   总被引:10,自引:0,他引:10  
陈鹏  周琪 《上海环境科学》2001,20(7):309-311
在普通氧化塘(SP)的基础上,发展起来的高效藻类氧化塘(HRAP)具有停留时间短、水深浅、连续搅拌等特点,在氮、磷的去除上具有明显的优势。通过比较高效藻类氧化塘与传统氧化塘的不同特点,详细叙述了高效藻类氧化塘对有机碳、N、P和病原体的去除机制,以及阳光、温度、pH等因素对COD、NH4-N、P、病原体的去除和对藻类生长的影响,并展望了研究前景。  相似文献   
190.
The distribution characteristics of heavier or lighter pollutants released at different cross-sectional positions of a wide river is investigated with a well-tested three-dimensional numerical model of gravity flows based on Reynolds-Averaged Navier-Stokes equations and turbulence k-? model. By focusing on investigating the influences of flow and buoyancy on pollutants, it is found that while carrying by the river flow downstream: i) a heavier pollutant released from the cross-sectional side position, forms transverse oscillation between two banks with decreased amplitude, i.e. forms kind of helical flow pattern along the straight part of channel bed; ii) a heavier pollutant released from the cross-sectional middle position, forms collapse oscillation in the middle of the straight channel part with reduced amplitude; iii) in the downstream sinuous channel, heavier pollutant is of higher concentration on the outer side of channel bends; iv) a light pollutant released from the cross-sectional side position, slips partly to the other side of the river, resulting in higher concentrations on two sides of the channel top; v) a light pollutant released from the cross-sectional middle position, splits into two parts symmetrically along two sides of the channel top; vi) in the downstream sinuous channel, light pollutant presents higher concentration on the inner side of channel bends. These findings may assist in cost-effective scientific countermeasures to be taken for accidental or planned pollutant releases into a river.  相似文献   
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