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81.
This paper uses spatial, temporal, and use-intensity data for 27 major marine uses in Washington waters to feature a method for assessing potential use conflicts in a variety of scenarios. The study represents a first step towards quantifying potential conflicts within Washington’s Marine Spatial Planning (MSP) study area by using a cumulative analysis to highlight high- and low-use intensity areas and the novel Marine Potential Conflict Index (MPCI), which incorporates space, time, and intensity of use, to quantify pairwise potential conflicts between uses. About 10% of pairs of uses do not overlap spatially and are likely compatible with one another. Temporally, the number of uses peaks in July and August and falls during January and February. Additionally, the MPCI identified three important use types with a substantial degree of potential conflict: commercial fishing, tribal fishing, and shipping. External data were used in three cases to ground-truth the analysis, as a limited test of its utility in managing any potential conflict. This article assesses the extent of Washington’s existing marine uses along spatial, temporal, and intensity axes, and more broadly provides a straightforward way to examine potential conflicts between marine uses.  相似文献   
82.
21世纪是海洋的世纪,科学利用海洋资源、发展海洋经济是实现人类社会可持续发展的重要途径。海岛地区,要在新一轮竞争中抢占发展先机、实现新的跨越,必须加快产业结构调整,推动产业转型提质增效。对此,以长岛为例,对海洋产业结构优化进行了专题研究。  相似文献   
83.
以渤海湾沿海低地的QX02孔为研究对象,进行了沉积岩石学分析和底栖有孔虫统计,结合加速器质谱~(14)C测年和光释光(optically stimulated luminescence,OSL)测年,探讨了该孔记录的第Ⅱ海相层埋深和形成时代。第Ⅱ海相层厚度11.4m,记录相对海面高度-26.83~-15.43m。AMS~(14)C年龄表明,Ⅱ海形成于MIS 3早期、甚至更早。OSL年代学研究显示,Ⅱ海样品等效剂量离散度较高,并且主要集中在2个区间,计算得到新、老2个年龄阶段。基于OSL测年原理的常规判断,认为较老的83.5~62.6ka阶段系受曝光不充分组分的影响,通常采用较年轻的51.9~39.9ka阶段为QX02孔的Ⅱ海沉积年龄。但是,较老的一组年龄从新的视角,暗示了可能的原始沉积过程及相应的海侵发生时间,因而具有重要的年代学和沉积学意义。  相似文献   
84.
Due to strong remodification and sparse trace remnants, tectonic restoration is critical for the reconstructing of the paleography and basin-prototype in the multiple-cycles superimposed basin, which is also fundamental for the hydrocarbon exploration of the deep marine carbonate in the Tarim Basin. This study presents the tectonic framework of the transition phase from the Sinian to the Cambrian Period and its constrains on the paleography of the Cambrian in the Tarim Basin based on comprehensive analysis of new geochronology data, seismic data and regional tectonic data. The results showed that (1) there is a large regional unconformity between the Cambrian and Precambrian, suggesting a discontinuous deposition from the Sinian to the Cambrian that is contrary to the major view; (2) a broad flattened paleotopography formed before Cambrian Period, which is favorable for the wide epicontinental sea environment and a gentle homoclinal ramp platform development in the early Cambrian, and the residual basement low relief uplifts that influence the microfacies differentiation in the carbonate platform; (3) the Cambrian carbonate platform has been involved much into the marginal orogenic belts, and the proto-platform is probably of 200 km out of the present basin in S-N direction; (4) there is a weak extensional setting in the Cambrian-Early Ordovician rather than a strong rifting setting with a large aulacogen into the platform, in which a inter-platform shallow depression and stable ramp platform developed in the Cambrian; (5) there is not troughs, but rather low relief uplifts developed in the Early Cambrian in the southwestern Tarim Basin, and lack of large uplifts along the carbonate platform margins; (6) it is showed a broad architecture of platform-wide slope-ocean basin from the inner Tarim plate to its margin in the Cambrian Period. Considering the basin prototype, the restoration of the tectono-paleography in the early Cambrian in the Tarim Basin is distinct from those of the previously proposed. We propose that a gentle pattern with “two platforms and one inter-depression” in E-W striking other than multiple small platform constrained in the basin, and further subdivision of the western platform with inner platform low uplift and sag in N-S striking, which is possibly inherited from the basement architecture. On the outer of the united platform, there is probably broad gentle slope for transition to ocean basin. We therefore argue that tectonic restoration is crucial for reconstruction of the paleogeography and basin prototype, especially for basins experienced multiphase of tectonic cycles. © 2018, Science Press. All right reserved.  相似文献   
85.
《China Geology》2021,4(4):541-552
The intersection of the Kyushu-Palau Ridge (KPR) and the Central Basin Rift (CBR) of the West Philippine Basin (WPB) is a relic of a trench-trench-rift (TTR) type triple-junction, which preserves some pivotal information on the cessation of the seafloor spreading of the WPB, the emplacement and disintegration of the proto-Izu-Bonin-Mariana (IBM) Arc, and the transition from initial rifting to steady-state spreading of the Parece Vela Basin (PVB). However, the structural characteristics of this triple-junction have not been thoroughly understood. In this paper, using the newly acquired multi-beam bathymetric, gravity, and magnetic data obtained by the Qingdao Institute of Marine Geology, China Geological Survey, the authors depict the topographic, gravity, and magnetic characteristics of the triple-junction and adjacent region. Calculations including the upward continuations and total horizontal derivatives of gravity anomaly are also performed to highlight the major structural features and discontinuities. Based on these works, the morphological and structural features and their formation mechanisms are analyzed. The results show that the last episode amagmatic extension along the CBR led to the formation of a deep rift valley, which extends eastward and incised the KPR. The morphological and structural fabrics of the KPR near and to the south of the triple-junction are consistent with those of the western PVB, manifesting as a series of NNE-SSW- and N-S-trending ridges and troughs, which were produced by the extensional faults associated with the initial rifting of the PVB. The superposition of the above two reasons induced the prominent discontinuity of the KPR in deep and shallow crustal structures between 15°N–15°30′N and 13°30′N–14°N. Combined with previous authors’ results, we propose that the stress produced by the early spreading of the PVB transmitted westward and promoted the final stage amagmatic extension of the CBR. The eastward propagation of the CBR destroyed the KPR, of which the magmatism had decayed or ceased at that time. The destruction mechanism of the KPR associated with the rifting of the PVB varies along strike the KPR. Adjacent to the triple-junction, the KPR was destroyed mainly due to the oblique intersection of the PVB rifting center. Whereas south of the triple-junction, the KPR was destroyed by the E-W-directional extensional faulting on its whole width.©2021 China Geology Editorial Office.  相似文献   
86.
Environmental NGOs are increasingly called upon to respect human rights when undertaking conservation programs. Evaluating a family planning program running alongside marine management measures in Madagascar, we find that family planning services provided by an environmental NGO can support women’s reproductive rights. Family planning services allow the option of smaller families, and give more time to work, increased income and better health. These benefits do not translate into increased support for, or participation in, marine management, however, and women who are able to work more are typically fishing more. We identify patriarchal norms as a key factor preventing the family planning programme from manifesting in improved resource stewardship, limiting opportunities for women to participate fully in resource management meetings and diversify their livelihood outside traditional tasks, including fishing. We propose that a successful human rights-based approach must be more comprehensive, targeting multiple rights and challenging existing institutions and power structures.  相似文献   
87.
随着社会经济的发展和海洋资源开发利用水平的提高,海上人工构筑物呈现种类、数量和规模都迅速增长的态势。但目前我国大部分海上构筑物尚未纳入统一的管理体系,导致管理权限不清和管理环节缺位。文章分析我国海上构筑物管理的现状和存在的问题,从海洋管理实践出发,对海上构筑物管理进行有益探索,提出在协调众多涉海部门的基础上,从审批、登记、竣工验收、弃置管理、事中事后监管等方面,解决最紧迫的管理需求,先易后难地完善海上构筑物管理的缺位环节,逐步建立和完善海上构筑物管理制度体系,更好地服务于海洋经济建设。  相似文献   
88.
Abstract

In the coastal area, nearshore and offshore structures have been or will be built in marine soft clay deposits that have experienced long-term cyclic loads. Therefore, the mechanical behavior of marine clay after long-term cyclic loading needs to be investigated. In this research, a series of monotonic and cyclic triaxial tests were carried out to investigate the postcyclic mechanical behavior of the marine soft clay. The postcyclic water pore pressure, shear strength and secant stiffness are discussed by comparing the results with the standard monotonic test (without cyclic loading). It is very interesting that the postcyclic behavior of marine soft clay specimen is similar to the behavior of overconsolidated specimen, that is, the specimen shows apparent overconsolidation behavior after long-term cyclic loading. Then relationship between the overconsolidation ratio and the apparent overconsolidation ratio is established on the basis of the theory of equivalent overconsolidation. Finally, a validation formula is proposed which can predict the postcyclic undrained shear strength of marine soft clay.  相似文献   
89.
海域动态监管业务是实施海域管理精细化、科学化的重要手段。文章从海域监管工作模式、海域使用动态监测、海域资源调查、分析评价与决策支持成果等方面对江苏海域动态监视监测业务进行梳理,以期为全国海域动态监管业务化拓展提供参考。  相似文献   
90.
上海海域海水水质变化趋势及应对措施   总被引:1,自引:0,他引:1       下载免费PDF全文
强化区域海洋生态环境评价,推进海洋生态环境监测体系建设,全面提升海洋环境保护监督管理效能,是上海建设全球海洋中心城市、发挥在"一带一路"倡议中桥头堡作用的必然要求。文章基于近年来上海海域环境质量监测资料,重点对无机氮、活性磷酸盐等海域主要污染物进行分析,结合流域来水与区域排污情况,阐明上海海域水质变化特征及总体趋势,并从体系建设、基础能力、执法监督、行业管理、生态修复与科技创新等方面提出合理化应对措施。  相似文献   
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