六六六(HCHs)在小白洋淀水生植物中的分布与富集

利用GC-ECD测定了小白洋淀6个采样点的9种浮水、挺水和沉水植物中4种六六六(hexachlorocyclohexanes,HCHs)异构体的含量,分析了其分布、组成及富集特征。结果表明:1)小白洋淀水生植物中总HCHs含量范围在ND~7.47 ng·g-1(ww),浮水植物中HCHs含量最高,挺水植物各组织含量也有明显差异,根部HCHs含量明显高于茎叶2种组织。2)4种HCHs异构体中,γ-HCH的残留水平要显著高于其他3种异构体。在沉水植物和浮水植物中,均以γ-HCH占绝对比例,相对含量达60%~99%;而在挺水植物中,δ-HCHs占有较高比例,并且主要富集在挺水植物的根部,茎中次之,叶中最少。3)小白洋淀浮水植物和沉水植物HCHs含量与水体中HCHs含量呈显著的正相关关系,而挺水植物荷花、蒲草中HCHs各组分含量与水体中HCHs的相关关系不显著。4)水生植物对水中HCHs的富集系数BCF在8.7~661.2范围;浮水植物的BCF最高,沉水植物次之,挺水植物的茎对水体中HCHs的BCF最低。     

Cost analysis of alternative methods for wastewater handling in small communities

Wastewater collection and treatment is quite important for sustainable management. It would be uneconomical and impractical to provide sewer systems and separate wastewater treatment plants (WWTP) for small communities. The decision process in wastewater planning is rather important in terms of comparing the alternatives considered. The two important points in the management of wastewater at rural areas not connected to a sewer system are to develop an optimized operation strategy and to make sure that the complete system is environmentally and economically sustainable. In some regions, package treatment could be an alternative solution. However, in cases where there is an existing large WWTP, a cluster system, where sewage generated by small communities could be transported via conveyors to a centralized WWTP, could be employed. In this study, the wastewater treatment and disposal problems in small communities were addressed and an alternative wastewater handling scenario was proposed. Additionally, three wastewater handling scenarios were compared. As a case study, Gebze villages were selected.     

小城镇污水处理实用工艺分析

小城镇污水治理不仅是小城镇自身发展的需要,同时也是流域生态环境保护的需要。本文简要地阐述了小城镇污水的特点以及小城镇污水处理的要求,指出小城镇污水处理工艺必须经济、高效、节能和简便易行。对适合于小城镇的几种常规污水处理工艺进行分析对比,并介绍了近年来出现的新工艺。     

Adaptation to Climate Change in Developing Countries

Adaptation to climate change is given increasing international attention as the confidence in climate change projections is getting higher. Developing countries have specific needs for adaptation due to high vulnerabilities, and they will in this way carry a great part of the global costs of climate change although the rising atmospheric greenhouse gas concentrations are mainly the responsibility of industrialized countries. This article provides a status of climate change adaptation in developing countries. An overview of observed and projected climate change is given, and recent literature on impacts, vulnerability, and adaptation are reviewed, including the emerging focus on mainstreaming of climate change and adaptation in development plans and programs. The article also serves as an introduction to the seven research articles of this special issue on climate change adaptation in developing countries. It is concluded that although many useful steps have been taken in the direction of ensuring adequate adaptation in developing countries, much work still remains to fully understand the drivers of past adaptation efforts, the need for future adaptation, and how to mainstream climate into general development policies.     

Change in frontline supervisors’ safety leadership practices after participating in a leadership training program: Does company size matter?

Introduction: The majority of construction companies are small businesses and small business often lack the resources needed to ensure that their supervisors have the safety leadership skills to build and maintain a strong jobsite safety climate. The Foundations for Safety Leadership (FSL) training program was designed to provide frontline leaders in all sized companies with safety leadership skills. This paper examines the impact of the FSL training by size of business. Methods: Leaders, defined as foremen or other frontline supervisors, from small, medium, and large construction companies were recruited to participate in a study to evaluate the degree to which the FSL changed their understanding and use of the leadership skills, safety practices and crew reporting of safety-related conditions. We used linear mixed modeling methods to analyze pre-post training survey data. Results: Prior to the training, leaders from small and medium sized companies reported using safety leadership skills less frequently than those from large ones. After the training, regardless of business size, we observed that the FSL training improved leaders understanding of safety leadership skills from immediately before to immediately after the training. Additionally, leaders reported greater use of safety leadership skills, safety practices, and crew reporting of safety-related conditions from before to two-weeks after the training. However, those from small and medium sized companies reported the greatest improvement in their use of safety leadership skills. Conclusions: The FSL training improves safety leadership outcomes regardless of the size company for which the leader worked. However, the FSL may be even more effective at improving the safety leadership skills of leaders working for smaller sized construction companies or those with lower baseline levels of safety leadership skills. Practical applications: The majority of construction companies employ a small number of employees and therefore may not have the resources to provide their frontline leaders with the leadership training they need to be effective leaders who can create a strong jobsite safety climate. The Foundations for Safety Leadership (FSL) training can help fill this gap.     

城郊型小城镇环境保护及生态建设初探--以扬州市邗江区甘泉镇为例

城郊型小城镇位于城乡结合部，由于受大城市的辐射，发展较快，做好城郊型小城镇的环境保护与生态建设具有重要的战略意义：本文以扬州市邗江区甘泉镇为例，探讨了城郊型小城镇环境保护及生态建设的思路。     

我国小城市固体废物区域管理系统中若干量化指标

简略介绍我国小城市的固体废物区域管理系统，指出在我国小城市固体废物实行区域管理的重要意义，系统论证了我国小城市固体废物区域管理中垃圾排放量，垃圾产生量的预测等若干重要量指标正确应用的意义与必要性。     

我国小城镇水污染控制战略的思考

我国广大小城镇的水污染形势目前正处在加刷状态，而由于我国小城镇的具体国情，决定了小城镇的小污染不能采取与大中城市“同构”的控制措施，本文结合我国小城镇的具体特点，从战略角提出了以建设生态型小城镇为导向，以控制乡镇企业水污染为核心，以控制导流－生态工程为最终出路的小城镇水污染控制模式。     

小流量污水处理工艺——OxiSequencer

介绍了一种针对小流量污水现场处理的工艺－－OxiSequencer。解释了工艺的基本原理、特点和应用等情况。说明OxiSequencer是一种适于分散小流量污水现场处理的系统。     

滴滤床在小城镇生活污水处理中的应用

针对小城镇生活污水的特点,开发出了以滴滤床为主的生活污水处理技术路线,讨论了滴滤床技术原理及其构造,分析了运行效果和运行成本,得出该技术具有处理效果好且水质稳定、操作简单,维护量小,符合国家倡导的"高效-低耗的城镇污水处理技术".