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41.
The first step to defining the rights, responsibilities and interests of stakeholders and constructing a compensation mechanism is to identify the stakeholders and clarify their mutual relationships. Nature reserves are complex ecosystems involving nature, the economy and society. There exists a conflict between the public welfare benefits of ecological conservation and the private gains to be realized from social and economic development. There also exist in a nature reserve complex relationships among stakeholders, involving the utilization of ecological resources, ecological conservation and ecological-economic interests. The introduction of tourism brings substantial changes to the existing stakeholder benefit structure in a nature reserve. The implementation of tourism ecological compensation (tourism payment for ecological service) is a process for redefining the distribution of rights, responsibilities and profits among stakeholders and it is also an essential way to balance the interests of the stakeholders. This paper uses a case study of Sanya Coral Reef National Nature Reserve in China to examine the characteristics of stakeholders and analyze their interests. According to the method for defining basic attributes proposed by Mitchel and other scholars, in cases of tourism ecological compensation, stakeholders can be classified as definitive stakeholders, expectant stakeholders and latent stakeholders. This paper applies these classifications and then analyzes the relationships between the rights and responsibilities of these stakeholders and how these change after the implementation of compensation. Additionally, based on the impact compensation has on different stakeholders, changes in the relationships can be analyzed and the structure of the stakeholders can be modelled. This case study of the Sanya Coral Reef National Nature Reserve illustrates the operationalization of a new mechanism for tourism ecological compensation. The paper illustrates a method for coordinating the relationships among the stakeholders involved with this national-level nature reserve. 相似文献
42.
《Marine Policy》2016
Located on the Caribbean coast of Central America and flanked by the second longest barrier reef in the world, Belize is a nation reliant upon marine resources. Each year, the country’s predominantly small-scale fisheries generate an estimated US$22 million in revenue – 1.8%of GDP – and employ 3000 people. However, the nation’s fishing communities are facing an unprecedented challenge. Existing threats posed by declining fish stocks have been exacerbated by the introduction of the invasive alien red lionfish Pterois volitans in 2008. This Indo-Pacific predator has the potential to cause significant losses to the recruitment of native fish, in turn disrupting coral reef community dynamics in the Belize Barrier Reef Reserve System, a UNESCO World Heritage Site. Howefver, targeted lionfish fishing may offer a cost effective means to control the invasion, while also creating an alternative livelihood solution and improving food security among Belize's coastal fishing communities. This study summarises the recent history of the lionfish invasion in Belize, describes the multi-sector approach being used to address the invasion, and presents preliminary research summarising the characteristics of invasive alien lionfish in Belize. Data from Belize's nascent ‘lionfishery’ are also presented, demonstrating that demand for lionfish is outweighing supply – largely as a result of awareness-raising initiatives – and highlighting the strong potential for replication of this approach elsewhere in the Caribbean. The study concludes by discussing the barriers and potential solutions to this market-based approach to invasive species management. 相似文献
43.
南沙群岛永暑礁岩体稳定性评价 总被引:2,自引:0,他引:2
永暑礁表层为松散的生物砂砾堆积,表层以下为礁灰岩,夹有2个沉积间断面。礁体呈岩盆结构,从外向内胶结程度依次降低。在综合研究了永暑礁自然环境特征、地层岩性以及岩体结构特征的基础上,认为永暑礁整体稳定性良好,不会发生整体倾覆的现象,浅层土体也不会发生剪切、滑移等工程地质问题。并利用非线性弹性本构模型,对永暑礁礁体地基与边坡在不同应力作用下发生变形与破坏的过程及机理进行了探讨,研究结果认为,在外部应力作用下,珊瑚礁内的应力状态将发生变化,局部出现应力集中,边坡出现拉应力。200kPa的荷载使礁体边坡产生的水平位移小于1cm,岩体边坡仍是稳定的,但最大垂直位移达到1.8cm,有可能出现珊瑚砂的整体剪切破坏。 相似文献
44.
Ocean waves can be destructive as steeper waves due to their high energy eroding the sandy beaches. During storm surge or high tide, the water level rises and if large waves occur, they will break closer to the beach, releasing enormous amount of energy resulting in strong currents. This causes heavy loss of beach material due to large-scale erosion. If these waves are made to break prematurely and away from the beach, they can be attenuated so as to reduce beach erosion. The reef, which is a homogeneous pile of armour units without a core, breaks the steeper ocean waves, dissipates a major portion of their energy and transmits attenuated waves. This paper experimentally investigates the armour stone stability of the submerged reef and the influence of its varying distance from shore and crest width on ocean wave transmission. 相似文献
45.
Multilevel governance is regarded as a promising approach to deal with the multidimensional nature of climate change adaptation. However, the policy context in which it is implemented is very often complex and fragmented, characterised by interacting climate and non-climate strategies. An understanding of multilevel decision-making and governance is particularly important, if desired adaptation outcomes are to be achieved. This paper examines how climate change adaptation takes place in a complex multilevel system of governance, in the context of Australia's Great Barrier Reef (GBR) region. It examines over one hundred adaptation strategies at federal, state, regional and local levels in terms of type, manifestation, purposefulness, drivers and triggers, and geographic and temporal scope. Interactions between strategies are investigated both at the same level of governance and across governance levels. This study demonstrates that multilevel approach is a necessary, but not a sufficient condition in responding to complex multiscale and multisector issues, such as climate change adaptation. Short-term adaptation measures; a predominant incremental, sectoral, top-down approach to adaptation; and the lack of a framework for managing interactions are major threats to effective climate adaptation in the GBR region. Coping with such threats will require long-term transformative action, establishing enabling conditions to support local adaptation, and, most important, creating and maintaining strategic interactions among adaptation strategies. Coordinating and integrating climate and non-climate strategies across jurisdictions and policy sectors are the most significant and challenging tasks for multilevel governance in the GBR region and elsewhere. 相似文献
46.
Regional models actively forced with data from larger scale models at their open boundaries often contain motion at different time-scales (e.g. tidal and low frequency). These motions are not always individually well specified in the forcing data, and one may require a more active boundary forcing while the other exert less influence on the model interior. If a single relaxation time-scale is used to relax toward these data in the boundary equation, then this may be difficult. The method of fractional steps is used to introduce dual relaxation time-scales in an open boundary local flux adjustment scheme. This allows tidal and low frequency oscillations to be relaxed independently, resulting in a better overall solution than if a single relaxation parameter is optimized for tidal (short relaxation) or low frequency (long relaxation) boundary forcing. The dual method is compared to the single relaxation method for an idealized test case where a tidal signal is superimposed on a steady state low frequency solution, and a real application where the low frequency boundary forcing component is derived from a global circulation model for a region extending over the whole Great Barrier Reef, and a tidal signal subsequently superimposed. 相似文献
47.
从区域地质背景、岩石学、岩石化学、微量元素、氧同位素及稀土元素组成等方面论证东川铜矿含铜“礁—硅岩组合”中的含铜硅质条带—硅质白云岩为海底喷流热水沉积成因;提出了该类层状铜矿的深源含铜富硅混合热液海底喷流—生物富集的沉积成岩成矿模式。并提出东川落雪式层状“马尾丝”铜矿含矿岩系为“含铜礁—硅岩组合”的新观点。 相似文献
48.
G. E. Mustoe 《地球表面变化过程与地形》1983,8(6):517-526
Tafoni and honeycomb weathering are abundant in sandstones at Capitol Reef National Park. Cavities are particularly common in talus blocks resting on alkali-rich soil, in vertical walls of desert washes, and in sandstones containing calcareous cement. Chemical analyses, X-ray diffraction data, and field observations suggest that salt weathering is the most important cause of disintegration, but dissolution of calcite cement also occurs in calcareous sandstones. Cavernous weathering at Capitol Reef produces cavities similar in appearance to features found in arkose outcrops along the coast of northwest Washington, even though the environmental conditions at these two locations are very different. 相似文献
49.
A new two-way nesting technique is presented for a multiple nested-grid ocean modeling system. The new technique uses the
smoothed semi-prognostic (SSP) method to exchange information between the different subcomponents of the nested-grid system.
Four versions of the new nesting technique are described, together with conventional one-way nesting. The performance of the
different nesting techniques is compared, using two independent nested-grid modeling systems, one for the Scotian Shelf of
the northwest Atlantic Ocean and the other for the Meso-American Barrier Reef System of the northwestern Caribbean Sea. Nesting
using the semi-prognostic method is shown to effectively prevent unrealistic drift of the inner model, while use of the SSP
method avoids unnecessary damping of small scales on the inner model grid. Comparison of the annual-mean flow field with the
near-surface currents determined by Fratantoni (in J Geophys Res 106:2977–2996, 2001) from observed trajectories of near-surface
drifters demonstrates the overall superiority of the nesting technique based on the SSP method. 相似文献
50.
浙江桐庐冷坞二叠纪生物礁的发育模式 总被引:4,自引:0,他引:4
礁体底部具脉状层理的潮坪相碎屑沉积,礁体内部藻叠层岩夹层的存在,及礁体上部为煤系地层覆盖等都表明冷坞生物礁是一个典型的二叠纪岸礁;海绵骨架岩的存在表明它是个骨架型岸礁。 相似文献