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61.
Long-term changes, from 1984 to 2010, in the indicators of microbial pollution (total viable count, coliforms, Escherichia coli, enterococci, and Clostridium perfringens) are analysed in the Riga Hydropower Plant Reservoir, an essential source of drinking water for Riga, the capital of Latvia. Counts in microbial indicators fluctuated seasonally and were related to physicochemical parameters (nitrogen compounds, turbidity, temperature, and pH). The changes in microbial pollution were brought about by two major socio-economic developments. Firstly, Latvia’s independence from the USSR in 1991 which facilitated a distinct reduction in most microorganism counts due to a sharp decline in industrial and agricultural production. This resulted in a significant drop in point and nonpoint pollution in the river basin. A further development was Latvia joining the European Union in 2004. The corresponding focus on water management, including wastewater treatment, was a major priority of environmental investment and lead to improvements in microbial water quality.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01470-1) contains supplementary material, which is available to authorized users.  相似文献   
62.
Nature-based solutions (NBS) find increasing attention as actions to address societal challenges through harnessing ecological processes, yet knowledge gaps exist regarding approaches to landscape planning with NBS. This paper aims to provide suggestions of how planning NBS can be conceptualized and applied in practice. We develop a framework for planning NBS by merging insights from literature and a case study in the Lahn river landscape, Germany. Our framework relates to three key criteria that define NBS, and consists of six steps of planning: Co-define setting, Understand challenges, Create visions and scenarios, Assess potential impacts, Develop solution strategies, and Realize and monitor. Its implementation is guided by five principles, namely Place-specificity, Evidence base, Integration, Equity, and Transdisciplinarity. Drawing on the empirical insights from the case study, we suggest suitable methods and a checklist of supportive procedures for applying the framework in practice. Taken together, our framework can facilitate planning NBS and provides further steps towards mainstreaming.Electronic supplementary materialThe online version of this article (10.1007/s13280-020-01365-1) contains supplementary material, which is available to authorized users.  相似文献   
63.
The use of molecular tools, principally qPCR, versus traditional culture-based methods for quantifying microbial parameters (e.g., Fecal Indicator Organisms) in bathing waters generates considerable ongoing debate at the science–policy interface. Advances in science have allowed the development and application of molecular biological methods for rapid (~2 h) quantification of microbial pollution in bathing and recreational waters. In contrast, culture-based methods can take between 18 and 96 h for sample processing. Thus, molecular tools offer an opportunity to provide a more meaningful statement of microbial risk to water-users by providing near-real-time information enabling potentially more informed decision-making with regard to water-based activities. However, complementary studies concerning the potential costs and benefits of adopting rapid methods as a regulatory tool are in short supply. We report on findings from an international Working Group that examined the breadth of social impacts, challenges, and research opportunities associated with the application of molecular tools to bathing water regulations.  相似文献   
64.
福州市城市化进程与大气污染关系研究   总被引:1,自引:0,他引:1  
以福州市为研究区域,选取福州市1996—2012年的时间序列数据,将大气污染物浓度作为被解释变量,城市化水平作为解释变量,分别设定二次曲线模型和三次曲线模型,通过比较PM10、SO2、NO2浓度与城市化水平的二次曲线和三次曲线模型的回归拟合效果,得出福州市大气污染与城市化水平之间的演化规律。结果表明,1996—2012年,福州市城市化水平平稳上升,城市的大气污染程度与城市化水平之间的关系并不完全符合"倒U型"的环境库兹涅茨曲线,不同的污染物类型具有不同的演化规律。PM10、SO2与城市化水平呈"倒N型"的曲线关系;NO2与城市化水平之间呈现"倒U型"曲线关系。由于研究的时间序列较短,因而研究结果可能只是真实曲线的一部分,福州市的大气污染与城市化水平之间的关系还有待进一步研究。  相似文献   
65.
Spontaneous combustion of sulfide concentrates can cause many serious problems during storage. In this study, two representative samples (sulfur-rich sulfide concentrate and iron-rich sulfide concentrate) were investigated for the self-heating behavior using the crossing-point temperature (CPT) method. The corresponding apparent activation energies were determined, 13.7366 kJ/mol for iron-rich sulfide concentrate and 21.3817 kJ/mol for sulfur-rich sulfide concentrate. Furthermore, the surface temperatures of sulfide concentrate stockpiles in different seasons were also measured by a thermal image apparatus. It was found the temperature for iron-rich sulfide concentrate stockpile was higher than that for rich-sulfur sulfide concentrate stockpile. These research results show iron-rich sulfide concentrate exhibits stronger propensity to spontaneous combustion than sulfur-rich sulfide concentrate. Particular attention should be paid to the fire hazard of iron-rich sulfide concentrate in daily safety check work. The combination of the CPT method with the infrared thermal image measurement provides a new approach for the risk assessment on the propensity of sulfide concentrates to spontaneous combustion during the production, storage and transportation. The useful data and experience achieved in this investigation can be also referenced in similar cases later.  相似文献   
66.
This paper presents the design and the implementation of a methodology for measuring and improving safety culture at a nuclear power plant (NPP). The study has involved the completion of a pilot project aimed at seeing how to make use of the RADAR logic (Results, Approach, Deployment, Assessment and Review) of the EFQM model as a tool for the self assessment of safety culture in a nuclear power plant. The work was aimed at finding evidence of the safety culture that was in place at the plant and at identifying both the strengths of that culture and any areas in which it could be improved. The score obtained from an analysis of those strengths and areas for improvement has made it possible to prioritise the actions to be taken. The identification of perceptions and evidence, the agreement on the strong points and areas for improvement and the quantification of the safety culture have been performed by groups comprising volunteers who work at the NPP. The advantages of this methodology are assessed in the paper.  相似文献   
67.

规划环境影响跟踪评价制度是规划环评制度的重要组成部分,完善跟踪评价制度对健全以环境影响评价制度为主体的预防体系具有重要意义。在分析我国规划环境影响跟踪评价制度与实践进展的基础上,系统梳理了现行制度存在的启动情形不明、程序亟待规范、约束力不足等问题,并从按照审查意见要求启动跟踪评价、保障生态环境部门知情权与建议权、强化违反跟踪评价义务的法律后果等方面提出对策建议,为《中华人民共和国环境影响评价法》的修订完善提供参考。

  相似文献   
68.
环境风险评价的实践与发展   总被引:8,自引:0,他引:8  
环境风险评价(Environmental Risk Assessment ERA)是环境影响评价的一个重要分支,主要分析评价环境中的潜在危险。本文围绕开展ERA的必要怀、国内外ERA发展现状等方面进行了评述,在此基础上针对目前ERA工作中的不足提出了三点建议。  相似文献   
69.
环境化学进展动态   总被引:1,自引:0,他引:1  
本文概述了近年来环境化学包括环境分析化学、环境污染化学、环境污染控制化学、生态化学等方面研究的一些新进展  相似文献   
70.
The environmental situation in Ghana is characterized by desertification, land degradation, deforestation, soil erosion, and inadequate water supply in the northern regions of the country. The population as a whole is growing at a rate of 3% per annum, with even greater urban growth rates, due to rural out-migration. Large parts of the coastal zone in the south are rapidly developing to become one large suburbanized area. Water quality is particularly threatened in the urban and industrialized areas, which are mainly located in the southern part of the country. The coastal lagoons and coastal waters are moderately to heavily polluted. Erosion extends along the whole Ghanaian coast with excesses, for example, in the Keta area, where during the last century over 90% of the original buildings have been washed awayby the sea. The obvious environmental consequences of the mining sector are illustrative of the environmental threats caused by a fast growing industry and industrializing agriculture, in a country where environmental policy is only in its formative years. Desertification, food insecurity and coastal erosion all contribute to an increasing number of environmental refugees. Environmental policy in Ghana is a post-Rio phenomenon. Environmental laws, a Ministry of Environment, Science and Technology, an advisory National Committee for the Implementation of Agenda 21, and a fully mandated environmental administration have been established. This administration advocates a progressive attitude towards environmental legislation and points out the specific utility of economic and legal instruments in environmental management in this relatively fast developing country. The choice of instruments for environmental management is increasingly influenced by the specific state of African environmental and technological capacity and by a call for the recognition of the role of traditional customs in nature conservation. This African perspective on environmental management is further intensified by an unmet need for regional, transboundary cooperation in the West African subcontinent. This specific West African context calls for an elaboration of an effective capacity-building program for environmental management in the area.  相似文献   
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