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61.
《Marine Policy》2016
A decade of international discussion on marine biological diversity beyond areas of national jurisdiction (BBNJ) culminated in 2015 with a United Nations General Assembly Resolution to establish an international legally-binding instrument on the conservation and sustainable use of BBNJ. Proponents of the new instrument therefore consider it as an opportunity to eliminate gaps in the current legal regime and promote better coordination. As the next step in the negotiations begins, substantial lessons can be drawn from the 1995 UN Fish Stocks Agreement (UNFSA), which has faced many of the same challenges related to gaps in scientific knowledge, uneven governance and regulatory capacities, and inherent unpredictability, both ecologically and in terms of anthropogenic drivers of change. For BBNJ, however, such challenges are far more complex due to the diversity of stakeholder communities and the diversity of resources involved, including fish and mineral resources with tangible economic values, marine genetic resources of unknown value, and the culturally-specific values attached to charismatic species and conservation in general. Drawing on lessons from UNFSA, it is argued that the establishment of marine protected areas (MPAs) under the BBNJ instrument would be particularly well served by a similar regional approach aligned with existing international agreements. In this regard, it is recommended that the capacity building under the new international instrument on BBNJ should focus inter alia on the secretariats of the regional fishery management organizations in order to enhance intra-regional and inter-regional cooperation and sharing of best practices. 相似文献
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The first part of the research reported here consists of an experimental campaign to study the scouring of a granular bed(glass beads, sand) induced by a dam break in an open channel. Two configurations are considered: with and without cylinders. In the second part of this study, the volume of fluid method coupled with the shear stress transport turbulent model and the lagrangian particle tracking method is used to simulate the local scour processes. The four-way coupling is realized by consider... 相似文献
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地下水硝酸盐污染已成为一个普遍的环境问题.为研究重庆金佛山水房泉岩溶地下河系统的硝酸盐来源与转化,于2017年4-10月每24 d左右对地下河系统内的某酒店自来水、化粪池、1#落水洞、水房泉4个采样点开展监测,进行水化学和δ15Nnitrate、δ18Onitrate同位素分析.某酒店污水经化粪池处理后,由1#落水洞排入地下河,最后在水房泉排泄.结果表明:①水房泉NO3-浓度范围为4.65~10.20 mg/L,相对于我国生活饮用水标准处于较低水平;化粪池、1#落水洞、水房泉3个采样点电导率和NO3-、Cl-浓度的高值期与游客人数增多对应关系较好.②某酒店自来水δ15Nnitrate值为3.7‰~5.8‰、δ18Onitrate值为1.6‰~2.7‰,说明硝酸盐主要来源为土壤有机氮,处于自然背景值;1#落水洞δ15Nnitrate值为14.4‰~21.1‰、δ18Onitrate值为3.5‰~11.2‰,显示硝酸盐主要来源为粪肥污水;化粪池和水房泉的δ15Nnitrate值为3.7‰~17.0‰、δ18Onitrate值为-9.0‰~7.3‰,表明硝酸盐主要来源为土壤有机氮与粪肥污水,显示其硝酸盐主要污染源是酒店生活废污水.③某酒店自来水、水房泉地下水的硝酸盐转化过程以同化作用为主;化粪池污水以硝化作用为主,是岩溶地下河系统硝酸盐的重要来源之一;1#落水洞污水表现为反硝化作用.④基于SIAR模型对水房泉的硝酸盐来源进行定量解析,发现大气降水、土壤有机氮和粪肥污水的贡献率分别为28%、36%和36%左右. 相似文献
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Understanding the connectivity of fish among different typical habitats is important for conducting ecosystembased management, particularly when designing marine protected areas(MPA) or setting MPA networks. To clarify of connectivity among mangrove, seagrass beds, and coral reef habitats in Wenchang, Hainan Province,China, the fish community structure was studied in wet and dry seasons of 2018. Gill nets were placed across the three habitat types, and the number of species, individuals, and body size of individual fish were recorded. In total, 3 815 individuals belonging to 154 species of 57 families were collected. The highest number of individuals and species was documented in mangroves(117 species, 2 623 individuals), followed by coral reefs(61 species,438 individuals) and seagrass beds(46 species, 754 individuals). The similarity tests revealed highly significant differences among the three habitats. Approximately 23.4% species used two habitats and 11.0% species used three habitats. A significant difference(p0.05) in habitat use among eight species(Mugil cephalus, Gerres oblongus, Siganus fuscescens, Terapon jarbua, Sillago maculata, Upeneus tragula, Lutjanus russellii, and Monacanthus chinensis) was detected, with a clear ontogenetic shift in habitat use from mangrove or seagrass beds to coral reefs. The similarity indices suggested that fish assemblages can be divided into three large groups namely coral, seagrass, and mangrove habitat types. This study demonstrated that connectivity exists between mangrove–seagrass–coral reef continuum in Wenchang area; therefore, we recommend that fish connectivity should be considered when designing MPAs or MPA network where possible. 相似文献
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陆地表层系统分类研究进展——从土地类型到地球关键带类型 总被引:1,自引:0,他引:1
陆地表层系统是多圈层相互作用下形成的综合体,具有时空异质性和层次性。对陆地表层系统进行多层级类型划分是识别其空间分异格局和演替规律的重要方法,可为多尺度地球科学系统研究和自然资源统一管理提供科学依据。陆地表层系统分类其实质是在特定尺度下对其组成要素间的空间和关系的划分,故土地类型、地表基质、关键带类型等都可归纳为陆地表层系统分类方案。论文在对国内外典型陆地表层系统分类方案进行梳理的基础上,将陆地表层系统分类总结为探索—发展—完善3个发展阶段。继而,对比了各分类体系内涵,提出各分类体系虽分属不同学派,但均是以陆地表层系统为研究对象,是研究陆地表层系统结构、功能和空间分异的方法论;分析了各分类体系结构的异同,总结了各分类体系在层级、比例尺和要素方面的共同特征。在此基础上,提出构建一套从地块到国家的陆地表层系统分类设想,并对等级体系、分类体系及分类方法集成3个方面进行了展望。 相似文献