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261.
《Marine Policy》2014
For nearly a decade, governments have been discussing the need to improve efforts to conserve and sustainably use marine biodiversity in areas beyond national jurisdiction (ABNJ). Support for a new international agreement under the United Nations Convention on the Law of the Sea (UNCLOS) – an Implementing Agreement – on the conservation and sustainable use of marine biodiversity in ABNJ has been growing. In June 2012, at the United Nations Conference on Sustainable Development held in Rio de Janeiro, Brazil, States agreed to take a decision on the development of an international instrument under UNCLOS before the end of the 69th session of the United Nations General Assembly (UNGA), which runs from September 2014 to August 2015. In follow-up to this commitment, it was agreed to consider the “scope, parameters and feasibility” of this instrument. To inform these international discussions, this article highlights some potential options for the content of a new UNCLOS Implementing Agreement. It first reviews the history of UN discussions, and then elaborates on options to address key elements identified as priorities for States in 2011: marine genetic resources, including the sharing of benefits, area-based management tools, including marine protected areas, environmental impact assessments, capacity-building and the transfer of marine technology. It addresses cross-cutting issues such as the governing principles, institutional structure as well as on other critical points such as High Seas fishing and flag State responsibilities. The article concludes with suggestions on possible next steps in order to succeed in the negotiations for an agreement. 相似文献
262.
长江口北支异常强盐水入侵观测与分析 总被引:2,自引:0,他引:2
长江口北支由于径流分流比很小,盐水入侵较强,特别是枯季大潮期盐水甚至倒灌进入南支,影响上海市和江苏省的水源地水质。为了进一步研究北支盐水入侵的规律及影响因素,2014年1月1-9日在北支进行了大小潮同步水文观测。本次观测到了北支异常强盐水入侵:小潮期发生强盐水入侵,且强度大于大潮期。小潮期强盐水入侵导致中下游河段被高浓度盐水控制,盐度从下游B01到中游B02几乎没有变化,且盐度的涨落潮变化几乎消失。分析认为,小潮观测期间长江入河口流量较小、河口潮差不是太小,加上强偏北风,三者的叠加是导致强盐水入侵的主要原因。 相似文献
263.
登陆或经过广西沿海的热带气旋是一种严重的自然灾害,每年热带气旋所伴随的大风、大雨、风暴潮等灾害造成沿海地区严重的财产损失或人员伤亡。通过对1950~2012年影响广西沿海的热带气旋的统计分析发现,影响广西沿海的热带气旋数量年际变化明显,最多的年份达9个,最少的年份为0个;热带气旋季节分布具有明显规律性,每年的7、8、9三个月为影响高峰月,其次为6、10月;热带气旋从菲律宾以东洋面进入南海后穿过海南省和雷州半岛再次登陆广西沿海的次数最多,该类热带气旋引起的风暴增水平均值为111.2 cm,到达非登陆台风增水的2.6倍。风暴潮灾害的形成与强台风天气系统、全日大潮、河流下泄洪水直接有关。强台风产生巨浪及降雨,使入海河口水位上升,与风暴潮叠加后产生明显的增水,造成巨大的潮灾。 相似文献
264.
历年影响广西沿海的热带气旋及其灾害成因分析 总被引:1,自引:0,他引:1
通过对1950-2012年影响广西沿海的热带气旋的统计分析发现,影响广西沿海的热带气旋数量年际变化明显,最多的年份达9个,最少的年份为0个;热带气旋季节分布具有明显规律性,每年的7、8、9三个月为影响高峰月,其次为6、10月;热带气旋从菲律宾以东洋面进入南海后穿过海南省和雷州半岛再次登陆广西沿海的次数最多,该类热带气旋引起的风暴增水平均值为111.2 cm,到达非登陆台风增水的2.6倍。风暴潮灾害的形成与强台风天气系统、全日大潮、河流下泄洪水直接有关。强台风产生巨浪及降雨,使入海河口水位上升,与风暴潮叠加后产生明显的增水,造成巨大的潮灾。 相似文献
265.
A comparison of Paleolithic and Epipaleolithic fisheries in NW Iberia shows an overall high trophic level of catch. Freshwater fisheries (and thus their impacts) are ca. 8000 yr older than marine fisheries and have suffered virtually no changes in the region except for the increase in numbers, being focused on two families (Salmonidae, and Anguillidae to a very minor extent). Marine fisheries in the Paleolithic likely had a low impact but rapidly increased in importance, raising the average trophic level of the catch, the number of affected taxa and the proportion of marine to freshwater fisheries with time. 相似文献
266.
Detailed, chronologically tightly constrained, lake-sediment-based geochemical and pollen records have enabled local changes in soil erosion, woodland cover and composition, and prehistoric farming impact to be reconstructed in considerable detail. The profile opens shortly after 7800 BC when tall canopy trees were well-established and presumably in equilibrium with their environment. A distinct perturbation that involved an increase in pine and birch, a decrease in oak and a minor opening-up of the woodland is regarded as the local expression of the 8.2 ka climate anomaly. Lack of response in the geochemical erosional indicators is interpreted as evidence for drier conditions. A short-lived, over-compensation in climate recovery followed the 8.2 ka event. Neolithic farming impact is clearly expressed in both the pollen and geochemical data. Both datasets indicate that Neolithic impact was concentrated in the early Neolithic (3715–3440 BC). In the interval 3000–2700 BC there appears to have been a break in farming activity. The pollen data suggest substantially increased farming impact (both arable and pastoral) in the Bronze Age, with maximum farming and woodland clearances taking place in the late Bronze Age (1155–935 BC). These developments are poorly expressed in the geochemical record, possibly due to within-lake changes. 相似文献
267.
Journal of Geographical Sciences - Land use/cover change (LUCC) is the foundation and frontier for integrating multiple land surface processes. This paper aims to systematically review LUCC... 相似文献
268.
The Chihuahua City region, located in the semiarid-arid northern highlands of Mexico, has experienced intensive groundwater abstraction during the last 40 years to meet water demands in the region. A geochemical survey was carried out to investigate the evolution from baseline to modern conditions of a 130-km flow path including the El Sauz–Chihuahua–Aldama–San Diego de Alcalá regions. The research approach included the use of major chemical elements, chlorofluorocarbons and environmental isotope (18O, 2H, 13C and 14C) tracers. Stable isotopes indicate that groundwater evolves from the evaporation of local rainfall and surface water. Groundwater located at the lower end of the flow section is up to 6000 years old and older groundwater in the order of 9000 years BP was found in a deep well located in the upper part of the flow system, implying contribution from a neighbour basin. The background groundwater chemistry upstream of Chihuahua City results from feldspar weathering. Beyond Chihuahua City the chemical conditions are strongly modified owing to disposal of sewage from public and industrial water supplies into the Rio Chuviscar, subsequent allocation of this water to agricultural irrigation areas and direct infiltration under the river bed. As a consequence, anions like chloride and sulphate are mainly related to surface sources. Nitrate is controlled in part by sewage from public supply and industry and in part by agricultural practices. Arsenic and fluoride are related to weathering of rock formations of local mineralized ranges and subsequent enrichment of the basin-fill by magmatic processes. The results of this study have implications for groundwater management in an arid region that depends entirely on groundwater for domestic, industrial and agricultural water consumption. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
269.
Abstract In the construction of global primitive equation models, based on the spherical harmonic method, two forms of truncation are in general use. Theoretical considerations suggest the triangular truncation method is superior, but the easily coded rhomboidal truncation is more commonly used. A verification experiment employing the Canadian Operational Spectral Model has been performed to determine if the theoretical superiority of the triangular truncation can be realized in practice. It was found that at least in the restricted case of extra‐tropical forecasts of less than 48 h, that the two truncation methods produced forecasts of equivalent accuracy. 相似文献
270.