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941.
《Marine Policy》2017
Marine spatial planning (MSP) is the leading tool for managing human activities at sea. It is designed to assist in decision making for marine resource access and use by considering the actions of those using the resources, interactions between these groups, and their cumulative impact on the natural environment. Being informed by ecosystem based management, MSP recognises that socio-natural systems are complex and that stakeholder and public input are key components of well-informed decision making. Therefore, MSP is rooted in the principles of good governance, including those of participation and transparency. This paper considers MSP processes in Scotland's inshore waters in the context of these good governance principles. The focus is on the institutional arrangements that allow stakeholders and the public to contribute to planning Scotland's seas and coasts. Whilst acknowledging the significant challenges faced by planners, and the work conducted so far, this research suggests that improvements could be made in how – and when – engagement takes place. It appears that at an early stage of introducing MSP in Scotland powerful stakeholders shaped the images, values and principles that guide it, and that including a broader range of actors early on might positively affect the legitimacy and acceptance of MSP in its later stages. The current institutional arrangements do not appear to allow for this. Ultimately, MSP in Scotland is in danger of institutionalising – and thus legitimising – existing power relations between marine resource users, and it does little to level the playing field. 相似文献
942.
三维探地雷达数值模拟中UPML边界研究 总被引:1,自引:0,他引:1
应用时域有限差分进行探地雷达正演计算时,边界条件的吸收效果是提高雷达波响应模拟精度的关键因素之一。这里推导出了三维各向异性完全匹配空间UPML吸收边界的计算公式,并编程实现。模拟结果表明:UPML吸收边界在吸收效果,反射误差及计算效率等方面,都明显优于常用的Mur、PML吸收边界,具有较好的模拟效果。采用三维UPML边界的时域有限差法,可以提高探地雷达正演模拟的可靠性、准确度。 相似文献
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944.
北京建设世界城市亟需解决的关键地质问题 总被引:1,自引:0,他引:1
北京建设世界城市对地质工作提出了更高的战略需求,需要创新城市地质工作分类,优选地质工作发展模式,研究和解决其可持续发展过程中的重大地质问题,构建与北京建设世界城市发展空间相适宜的区域工程地质勘查体系,确保北京可持续发展。 相似文献
945.
利滓县城区内的“城中村”因长期以来管理混乱,存在基础设施薄弱,安全隐患较多;缺乏整体规划,乱搭乱建严重;村庄建设与管理滞后,土地利用率不高等问题。为进一步缓解城市建设用地紧张的局面,提高“城中村”土地利用率,建议以坚持思想先导、规划先行、依法行政、建管结合、配套跟进等方式,采用加强组织领导、坚持科学规划、加强土地管理、制定工作方案、做好保障工作、制定扶持政策等措施,力争建设城市化的新利津。 相似文献
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948.
海河平原北部地区属于半干旱自然地理环境且仍在干化,自山前至滨海的山麓堆积-河流沉积-海陆交互沉积序列的平原地貌地质环境,土壤地球化学环境以高Ca、Mg、F,低Se、Mo、I和弱碱性为特征且正在经历酸化过程,潜水环境以淡水-微咸水-弱碱性为特征且有碱化的趋势。人为作用与自然作用一起构成了本区水土地质环境演化的双重驱动力,但在表现形式和区域分布方面驱动强度存在明显的差异性,土壤环境质量良好但潜水环境质量较差且均在恶化。 相似文献
949.
The existence of the upper mantle low velocity layer (LVL) below 100 km depth in cratonic areas is tested with surface waves dispersion curves. Given the ambient noise we find that a pronounced LVL (80 km thick and 2% velocity reduction or 40 km thick and 5% velocity reduction) can be distinguished from a constant velocity model by comparison of the fundamental mode group velocities, whereas a thin LVL (less than 40 km thick) with small velocity contrast (less than 2%) cannot be resolved. The fundamental modes of Love and Rayleigh waves have similar properties and, in general, the phase velocity differences are smaller than the standard error. Phase velocity alone cannot discriminate between the models, and the group velocity is in general more sensitive to the velocity structure than the phase velocity. The higher modes at short periods could potentially determine a LVL but in reality it is difficult to obtain sufficiently accurate measurements. We invert the synthetic dispersion curves by the non-linear Hedgehog inversion method. A pronounced LVL (more than 40 km thick and with a strong velocity contrast of about 5%) is detectable by the non-linear inversion but for a thin LVL with a strong velocity contrast it is not possible to resolve both velocity and thickness. In the inversions all solutions include a LVL for models with a pronounced LVL, whereas the solution space includes models with and without a LVL for models with a zero or positive gradient velocity–depth structure.We invert also real data with travel path across the Siberian craton with the Hedgehog method. Almost all solutions include a LVL in the depth range of 80–150 km with a velocity contrast up to 2% to the surrounding intervals. Hence, the LVL appears to be a common feature of the Siberian upper mantle, although a constant velocity at the same depth range cannot be totally excluded. Despite low resolution at large depth, a pronounced asthenospheric LVL below a depth of about 225 km is a constant characteristic of the set of solutions. 相似文献
950.