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241.
Artisanal fishing is an activity which has long occupied an important place on the West African coast. In less than 20 years, the increasingly widespread use of motors in fishing boats and cold storage facilities both on board and on land have enabled fishermen to master the constraints of space and time. Furthermore, globalization has created a demand for new products, thus influencing the behaviour of fishermen and consequently the status of some fish, turtle and marine mammal species. Development policies for artisanal fishing do not adequately reflect the importance of these changes. They tend to use inappropriate scales of reference, be it spatially (national borders take precedence over ecosystems) or temporally (the long-term consequences of development plans are seldom considered). Some international conservation organizations are testing promising new approaches to managing resources more sustainably and restoring degraded ecosystems, and their recent experiences can serve as useful examples to others. It is recommended to grant special rights of access to resident fishermen. In defending ‘their’ resources, they will also protect the ecological functions of the area. Close collaboration with administrations and development assistance agencies is needed to assess consequences of political decisions on the use of resources. The important role of marine protected areas as a tool for fishing management should be better documented and strengthened. These areas should not be considered as isolated units but rather as vital parts of a comprehensive system for improved coastal zone management. Consistent with the ecosystem approach, fishermen and their communities, being the main users of coastal resources, should also play a major role in the design and implementation of any fishing management actions.  相似文献   
242.
The spring waters of Tuzla–Icmeler are on the Marmara Sea coast in Tuzla town of Istanbul city. The springs discharge a natural sodium chloride mineral water that consumed for ages for therapeutic purposes attributed to their chemical properties. Development of springs commenced during the Ottoman times and a surface collection structure was built at the discharge point of the main spring. Two deep wells were drilled to tap mineral water within the past decades. The bottled water of these springs is also sold for a couple of years and its consumption as a beverage is increasing. The geochemical properties of these springs were investigated by several researchers in the past. This study comprises geochemical and geophysical measurements performed between July 2001 and July 2002 in order to construct a conceptual hydrogeological model for environmental and land use planning purposes. The seasonal evaluation of Tuzla–Icmeler (mineral spring) shows that the chemical properties fluctuate from the beginning of summer until the beginning of winter. This indicates that the overdraft of water during the summer season causes the movement and mix of normal groundwater with the mineralized groundwater. As a result, mixing of less mineralized groundwater decreases the salinity of mineralized groundwater. Using the site-specific hydrogeological, geochemical and geophysical data, zones of protection areas were delineated in order to prevent a possible pollution access to the springs and surroundings from nearby dockyards, dwellings and vehicle traffic. For this purpose, a new land use plan was proposed using the existing settlement sustainability plans.  相似文献   
243.
以成渝经济区主要水系水体沉积物为研究对象,利用Eri(单一金属潜在生态风险因子)和RI(多金属潜在风险指数)等定量诊断工具分析沉积物中的重金属的潜在生态风险,为成渝经济区战略环评提供数据支撑。根据风险指标评价结果和重金属空间分布规律,将区域水系分为3种生态风险功能区。结合沉积物中重金属赋存形态,得出区域Cd的生态风险较...  相似文献   
244.
通过雨水径流的集蓄储存可解决水源问题,发展山地蔬菜大棚。结果表明:一个70m^3的水窖集水在配以渗灌技术的条件下可以满足333m^2的大棚生育期用水需求,与传统畦灌相比节水53.4%,且效益可观,达20万元/hm^2,使干旱贫瘠的山地一跃成为发展高效农业的园田,为辽西易旱区坡地高效利用开辟了一条新途径。  相似文献   
245.
Following a toxic hazmat release, decisions need to be made vis-a-vis a safe evacuation distance for population along the transportation route, or whether to shelter-in-place if there is insufficient time to conduct an evacuation. The first responder may have to take these decisions through a quick estimation of the Initial Isolation Zone (IIZ) and protective action distances based on assumed rate of releases. Real-time evacuation planning models could be used for effective evacuation purposes. However, factors that usually were taken into account include weather conditions, population density, time of day, and uncertainty about the chemicals involved and/or the accumulating concentrations in public areas. Emergency planning including evacuation in India is generally in line with UNEP's APELL (Awareness and Preparedness for Emergencies at Local Level) methodology. However, quantitative risk based assessment is catching up particularly in large industrial zones. The paper highlights a case study of the evaluation of identified seven critical evacuation planning zones along three highway study routes in and around the industrial city of Surat in western India. The elapsed time after a release is estimated through ALOHA and evacuation travel time estimates are made for each zone. For identified scenarios, evacuation of IIZ, generally comprising of road side population, is effectively possible in six out of seven identified emergency planning zones except in zone-7, where certain people would still be exposed, as full evacuation may not be achieved. However, shelter-in-place would be advisable for population residing in permanent settlements within the protective action zone.  相似文献   
246.
The paper proposes an imprecise Fault Tree Analysis in order to characterize systems affected by the lack of reliability data. Differently from other research works, the paper introduces a classification of basic events into two categories, namely Initiators and Enablers. Actually, in real industrial systems some events refer to component failures or process parameter deviations from normal operating conditions (Initiators), whereas others refer to the functioning of safety barriers to be activated on demand (Enablers). As a consequence, the output parameter of interest is not the classical probability of occurrence of the top event, but its Rate of OCcurrence (ROCOF) over a stated period of time. In order to characterize the basic events, interval-valued information supplied by experts are properly aggregated and propagated to the top. To this purpose, the Dempster–Shafer Theory of evidence is proposed as a more appropriate mathematical framework than the classical probabilistic one. The proposed methodology, applied to a real industrial scenario, can be considered a helpful tool to support risk managers working in industrial plants.  相似文献   
247.
The conflict between city development and urban carrying capacity is getting ever prominent. In order to study and predict the restriction factors and prominent problems in the development of the Shandong Peninsula Blue Economic Zone as well as promote the transfer of economic development pattern in this region, this study starts from four single factor carrying capacity indicators of water, earth, transportation and environment in the city and its comprehensive carrying capacity indicator, evaluates and analyzes its carrying capacity and then papooses policy suggestions for improving its carrying capacity.  相似文献   
248.
长江中游城市群区域一体化的测度与比较   总被引:1,自引:0,他引:1  
实现长江中游城市集群区域一体化,既能承接东部地区产业转移,也能够向西部传递发展势能,缩小西部与中东部的差距。参照了世界银行从密度、距离与分割3个维度对区域一体化的界定,构建了区域一体化评价体系;采用2000~2010年数据,并结合层次分析法对长江中游城市集群内部区域一体化进行测度与比较分析。研究显示:(1)长株潭城市圈区域一体化水平最高,武汉城市圈次之,环鄱阳湖生态经济区最低,但三大城市群一体化水平都呈现逐渐增长趋势;(2)三大城市群在市场一体化、行政一体化及社会一体化变化水平差异明显但总体差距逐渐缩小;(3)武汉城市圈在“两型”社会建设推动下一体化水平稳步提升,长株潭城市群一体化水平进程最快,环鄱阳湖生态经济区后发优势明显。在此基础上,提出了构建长江中游城市集群经济发展联动机制的政策建议  相似文献   
249.
关于工业园区建设中环境保护问题的若干思考   总被引:1,自引:0,他引:1  
李文明 《重庆环境科学》2003,25(8):28-30,36
为促进块状经济集聚升级,应对加入WTO以后的压力,弥补个私企业规模缺陷等经济发展进程中的问题,需要加快特色工业园区建设。如何使特色块状经济与环境保护良性互动,实现经济效益、社会效益、环境效益的三统一,促进社会经济的可持续发展。本文结合诸暨经济、环境现状,提出了在加快特色工业园区建设的同时,要重视解决环境问题。为此,提出在工业园区建设中,要编制环保规划、进行环境影响评价、严格执行“三同时”制度、推行清洁生产和ISO14000体系认证、实行污染集中治理和专业化治理污染等方面的对策及建议。  相似文献   
250.
王影  柴立和 《环境科学学报》2016,36(5):1859-1865
生态承载力是可持续发展研究的核心.本文基于生态承载力的内涵,从4个方面构建了生态承载力的评价指标体系,并以最大信息熵原理(MIEP)为基础,自组织特征映射神经网络(SOFM)为算法,借助MATLAB数学软件为计算平台,从复杂系统结构演化的角度提出了生态承载力评价模型,并用MIEP模型对洞庭湖生态经济区2008—2012年的生态承载力进行评价,以指导当地生态建设.结果表明,5年间该地区的生态承载力呈总体上升的趋势,其中,2008年和2009年两年生态承载力水平基本一致,2010年呈现较明显的上升,2011年的生态承载力剧烈下降后在2012年呈现大幅回升.ξ值各分量的雷达图揭示出各指标逐年贡献程度的变化,结合准则层面的分析发现,水资源发展状况对该地生态承载力整体水平影响较大.与主成分分析法的比较表明了MIEP模型对生态承载力评价的可行性,同时其能更好地体现生态承载力发展演变的动力学特性,连接权值的获取避免了人为设定的主观性,在评价中有明显优势,且在预测上有一定潜力.  相似文献   
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