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271.
Eight conventions make up the biodiversity cluster of multilateral environmental agreements (MEAs) that provide the critical international legal framework for the conservation and sustainable use of nature. However, concerns about the rate of implementation of the conventions at the national level have triggered discussions about the effectiveness of these MEAs in halting the loss of biodiversity. Two main concerns have emerged: lack of capacity and resources and lack of coherence in implementing multiple conventions. We focused on the latter and considered the mechanisms by which international conventions are translated into national policy. Specifically, we examined how the Strategic Plan for Biodiversity 2011–2020 and the associated Aichi Biodiversity Targets have functioned as a unifying grand plan for biodiversity conservation. This strategic plan has been used to coordinate and align targets to promote and enable more effective implementation across all biodiversity-related conventions. Results of a survey of 139 key stakeholders from 88 countries suggests streamlining across ministries and agencies, improved coordination mechanisms with all relevant stakeholders, and better knowledge sharing between conventions could improve cooperation among biodiversity-related conventions. The roadmap for improving synergies among conventions agreed to at the 13th Convention on Biological Diversity's Conference of Parties in 2016 includes actions such as mechanisms to avoid duplication in national reporting and monitoring on conventions and capacity building related to information and knowledge sharing. We suggest the scientific community can actively engage and contribute to the policy process by establishing a science-policy platform to address knowledge gaps; improving data gathering, reporting, and monitoring; developing indicators that adequately support implementation of national plans and strategies; and providing evidence-based recommendations to policy makers. The latter will be particularly important as 2020 approaches and work to develop a new biodiversity agenda for the next decade is beginning.  相似文献   
272.
国际河流管理合作模式的分类及演进规律探讨   总被引:2,自引:1,他引:1  
论文对国际河流管理合作模式的概念、分类及演进规律进行了探讨。在从合作主体、目标、途径、制度等方面对合作模式进行单维度分类的基础上,借鉴霍尔三维结构图系统分析方法,构建了合作模式三维度分类模型,较全面、准确地概括了当前国际河流管理合作实践的模式类型。最后,综合世界各种典型国际河流管理合作模式的形成和发展过程,从模式要素的发展演变及模式演进的动力机制两个方面入手,详细阐述了国际河流管理合作模式的演进规律。  相似文献   
273.
Fish is the main food in coastal areas and its analysis for toxic metals has been used as an indicator of the pollution status of the aquatic environment. Several different fish species from the three Indian coasts, Visakhapatnam in the east, Mumbai in the west and Mangalore in the south west and also inland freshwater fish from Nagpur in the central region for comparison were analyzed for up to 20 elements (As, Au, Ba, Br, Cl, Co, Cr, Cu, Fe, Hg, K, Mn, Na, P, Rb, Sb, Sc, Se, Sr, Zn) by instrumental neutron activation analysis (INAA). Dried fish samples in powdered form were irradiated with thermal neutrons in a nuclear reactor followed by high resolution gamma ray spectrometry at different intervals. Several Reference Materials (RMs) of biological origin were analyzed for quality assurance and data validation. Elemental contents in different fish species vary in a wide range depending on the species, its size, location, and aquatic environment. Fish from Mangalore showed highest mean contents of Cr (14.8?±?29.9?µg?g?1), Cu (1005?±?643?µg?g?1) and Sb (849?±?888?ng?g?1) whereas those from Mumbai exhibited highest Hg (2066?±?2146?ng?g?1) and P (20.3?±?4.63?µg?g?1) but lowest Cu (6.30?±?3.10?µg?g?1) contents. Fish from all the regions showed significant amounts of nutrient elements such as Na, K, P, Mn, Fe, Se and Zn as well as some pollutant elements (Br, Cr, Sb, Hg). No regularity in variation of elemental contents with the size was observed. Prawn (Panaeus latisulcatus), a popular fish species from four different regions showed wide variation in elemental contents of Cr, Mn, Fe, Zn, Se, P including toxic pollutants, Sb and Hg. An attempt has been made to calculate daily dietary intake (DDI) for some nutrient elements from Indian fish. Elemental data for Cr, Cu, Fe, Hg, Se, and Zn have been compared with those from other fish exporting countries.  相似文献   
274.
Metal concentrations were determined in water, sediment, and freshwater fish samples (Squalus cephalus, Barbus esocinus, and Barbus xanthopterus) collected from Karakaya Dam Lake, Turkey, to estimate the risk of human consumption and pollution. Metal concentrations differed between the species (p??Zn?=?Cu in water and Fe?>?Zn?>?Mn?>?Ni?>?Cu in sediment. In general, the accumulation order of elements in the tissues all of the species sampled were found as Fe?>?Zn?>?Se?>?Mn?>?Cu?>?Ni?>?Cd in muscle, Zn?>?Fe?>?Mn?>?Se?>?Cu?>?Ni?>?Cd in gills, Fe?>?Zn?>?Se?>?Mn?>?Cu?>?Ni?>?Cd in liver and gonad, and Zn?>?Fe?>?Cu?>?Mn?>?Se?>?Ni?>?Cd in kidney. It was concluded that the fish from the dam lake are not heavily burdened with metals, but they should be controlled periodically to avoid excessive intake of trace metals by humans, and to monitoring the pollution of aquatic environment.  相似文献   
275.
The seasonal variations of Cd, Pb, and Cu in the water, sediments, and freshwater fish (Hypophthalmichthys molitrix, Cirrhinus molitorella, and Oreochromis mossambicus) of four lakes in Hanoi, Vietnam, were investigated. Samples for analysis were taken four times from April 2010 to March 2011. The levels in water were lower than the Vietnamese standards, except for Pb, but they were all much higher than the Canadian standards for protection of aquatic life; in the sediments, they were higher than world average levels. Bioaccumulation of the three metals in fish was site-dependent and species-dependent, but correlations of their levels in fish to those in water and sediments were weak. Levels of Pb in fish exceeded those of the UK and the WHO standards, and the recommended values of Vietnam for human consumption. Overall, the results show that the lakes are polluted with these metals, and consumption of high quantities of fish from them may be problematic. The outcome of this research helps to establish background data for future monitoring.  相似文献   
276.
Going ‘green’ is more than a mere fad in the hotel industry, and environment-friendly green hotels are becoming popular. The purpose of this study was to conduct an investigation into the link between ‘green’ and cost efficiency in the hotel industry. Empirical evidence supporting this investigation was gathered from the Taiwan hotel industry. Data were gathered from 68 international tourist hotels in Taiwan. Moreover, our finding differs from most of the earlier studies and indicates that ‘green’ is negatively and significantly associated with the cost efficiency of a hotel. In other words, ‘green’ renders a hotel ineffective. The implications of the findings have been discussed, and the limitations of the study as well as future research directions have been addressed.  相似文献   
277.
陈自祥  柳后起  刘广  刘颖  尹雪斌 《环境化学》2012,31(12):1855-1864
氮营养盐污染在全球很多区域都是一个备受关注的环境问题,尤其是以农业为主的区域和人口密集的区域,因此,关于水体中氮污染源识别技术尤为重要.硝酸根离子中的氮、氧同位素组成在过去的十几年中频繁地应用于识别淡水水体中氮污染源的研究中.本文总结了已知氮污染源中氮、氧同位素组成的特征变化区间,阐述了影响氮、氧同位素组成的主要因素,描述了3种氮、氧同位素组成主流的测试方法,展望了未来定量测算各种氮污染源贡献比例的前景.在实际研究中,还将氮、氧同位素组成和水体化学特征结合,则可以有效地识别淡水水体的氮污染源.随着检测精度的不断提高,各种代表性端元污染物同位素值经验区间也变得更加准确.  相似文献   
278.
国际河流管理和内河流域管理比较研究   总被引:2,自引:0,他引:2  
传统来看,国际河流和内河在管理模式、政策、法规上从来都是各自为政的。然而,利益主体的多元性,河流自身生态系统的统一性都说明了这两种河流的管理,包括合理利用和有效保护,具有共通之处,因此,成功的国际河流管理经验可以内河的利用保护所借鉴。在将国际河流保护制度和内河管理制度惊醒比较之后,本文试图从对比中思考我国内河流域管理立法模式、流域管理机构的地位和如何协调流域内部利益。流域管理不应单独立法,流域管理机构的地位在新《水法》中有所明确,但其职责还需进一步向统一宏观规划调度的方向定位,由流域管理机构根据公平合理地原则进行流域内部利益协调。只有将流域管理机构和协调流域内部利益紧密结合起来,才是流域可持续发展的关键。  相似文献   
279.
淡水沼泽湿地泥炭沉积中氮素分布特征   总被引:5,自引:1,他引:4  
采用冬季采样,现场分层的方法,系统地研究了我国面积最大的淡水沼泽湿地--三江平原沼泽湿地中河床-河漫滩型泥炭地和谷底洼地型泥炭沉积中TN、NH4+-N和NO3--N的分布特征.结果表明,在不同沉积层中,NH4+-N、NO3--N明显富集于Aso层,TN在Hil层含量最高.TN含量随着泥炭粒级的减小而明显增加,NH4+-N主要分布在粒级0.149~0.074mm的泥炭机械组分中,NO3--N主要分布在粒级0.03~0.149mm的泥炭机械组分中.  相似文献   
280.
论述了进口可再生利用废塑料在环保、节能减排等国民经济领域中的重要意义。通过分析统计数据,阐明了我国由于资源匮乏,进口可再生利用废塑料的必要性和迫切性,并简述了我国政府对废塑料进口的监管措施。  相似文献   
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