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951.
Bayesian belief networks are finding increasing application in adaptive ecosystem management where data are limited and uncertainty is high. The combined effect of multiple stressors is one area where considerable uncertainty exists. Our study area, the Great Barrier Reef is simultaneously data-rich – concerning the physical and biological environment – and data-poor – concerning the effects of interacting stressors. We used a formal expert-elicitation process to obtain estimates of outcomes associated with a variety of scenarios that combined stressors both within and outside the control of local managers. There was much stronger consensus about certain stressor effects – such as between temperature anomalies and bleaching – than others, such as the relationship between water quality and coral cover. In general, the expert outlook for the Great Barrier Reef is pessimistic, with the potential for climate change effects potentially to overshadow the effects of local management actions.  相似文献   
952.
黄河三角洲土壤盐渍化原因分析与生态风险评价   总被引:4,自引:0,他引:4       下载免费PDF全文
以黄河三角洲为研究区域,选择土壤全盐为标志,以海拔高程、地下水位、地下水矿化度、、灌溉排水状况、土壤有机质和人口密度6个土壤盐渍化主要控制性因子,采用聚类分析方法进行了土壤盐渍化原因分析;基于ArcGIS 9.3和Matlab,选择上述7个要素为评价因子,以归一化植被指数(NDVI)为生态终点,利用灰色关联度方法建立了区域土壤盐渍化的生态风险评价模型,并进行了生态风险评价。结果表明:黄河三角洲土壤盐渍化主要受自然和人为因素驱动,其中地下水位和海拔高程等自然因素是造成研究区土壤盐渍化的自然因素,土壤有机质和人口密度等是人为因素;土壤盐渍化极大和重度风险区域集中分布于黄河三角洲东南沿海区域、西北沿海、东北部的部分地区,该区域受海洋影响强烈,土壤盐渍化面积最大,占到总面积的58%以上;无风险、轻度风险和中度风险区域主要与黄河径流的距离有关,且随着距离增大而风险增加。  相似文献   
953.
Worldwide demand for energy is growing and predicted to increase by up to three times by 2050. Renewable energy will play a vital role in meeting this demand whilst maintaining global climate change targets. Around the British Isles, development of wind farms has entered Round three, with large, high capacity wind parks being planned to enhance energy security and achieve 2020 renewable energy targets. Such developments place additional pressure on existing sea space and may result in conflicts with other marine activities and users. Co-location of certain activities, marine protected areas, aquaculture and commercial fishing in particular, has therefore been proposed as an option to ease demands on space. Using the UK guided by EU and regional policy, as a case study, following the criteria-based planning system, co-location is legally feasible. Crucially, co-location options will depend on site specific characteristics and site management plans. The biology, ecology and hydrology of the site as well as consideration of important commercial and economic factors will be determining factors of success. For marine protected areas compatibility with conservation objectives for the site will be fundamental. Where possible, it is suggested that activities suitable for co-location will develop in tandem with renewable energy projects. The importance of developing joint projects in this manner is particularly true for aquaculture projects to ensure tenure security and commercial viability. Adaptive management will be a basis for evolution of the concept and practice of co-location. Pilot projects and continued monitoring will be essential in shaping the future of co-location of activities. As the Marine Management Organisation continues the development of marine plans for the English inshore and offshore waters, a study into potential solutions for resolving sea use conflicts is timely. This paper therefore provides a concise overview of the current regulation affecting co-location of key marine activities within wind farm zones and provides suggestions on how co-location projects can be adopted and taken forward, using the UK as a case study.  相似文献   
954.
Marine and coastal policy in the UK has faced a number of significant changes in recent years, most notably the passing of the Marine and Coastal Access Act in 2009. These changes have brought significant challenges and opportunities for all those involved in the management and use of the UK's marine and coastal environment. This new era of marine policy inspired the UK's first Marine and Coastal Policy forum held in June 2011. In this introductory paper the global context of marine policy changes and the themes which emerged from the forum, forming the basis of the articles in this special issue, are outlined. It is concluded that there is a high level of engagement, capacity and willingness of key stakeholders to work collaboratively to address the environmental, social and economic complexities of managing the marine and coastal environment. It is both evident and encouraging that progress is being made and the many challenges faced in this new era give rise to a number of opportunities to develop new ideas and effective mechanisms for finding solutions.  相似文献   
955.
Artificial surfing reefs (ASRs) are a new breed of coastal engineering structures claimed to enhance local biodiversity, provide coastal protection and improve wave quality for surfing. By providing multiple functions ASRs are often expected to contribute positively to the local economy, especially through tourism related to surfing and other water sports or beach uses. However, there is a lack of independent studies to support this expectation. This study investigates the claims that an ASR will enhance a coastal economy through tourism. Using Boscombe ASR, UK as a case study a preliminary evaluation of visitor expenditure is conducted. Using targeted face-to-face questionnaires we gathered data from 523 seafront visitors over a 32 month period. Results show that the ASR initially acted as a tourist attraction after which the novelty wore off. However, the positive impacts of the seafront regeneration scheme on the local economy are longer lasting. Contrary to the original claims that the Boscombe ASR would attract an affluent surf market, surfers and water users interviewed in this study are low spenders and rarely stayed overnight in Boscombe. Although it has been demonstrated that the expenditure of surfers is not as high as expected, more affluent non-surfer visitors have been attracted by the marketing associated with the new surfing resort. The results of this study have led to the following recommendations with respect to the establishment of artificial surf reefs: a period of stakeholder consultation with surf community and local community is required to determine whether an ASR is desirable; robust impact assessments of the reef must be carried out by independent parties before a marine licence is granted; expectations of the community must be managed through honest marketing and careful media coverage; planning must include a contingency for the cost of maintenance, repair and even removal if the structure fails to deliver; and further research is required to determine the full social and economic potential of artificial surf reefs.  相似文献   
956.
There is a well-established scientific field – decision science – that can be used to rigorously set conservation priorities. Despite well-documented shortcomings, additive scoring approaches to conservation prioritization are still prevalent. This paper discusses the shortcomings and advantages of both approaches applied in Fiji to identify priorities for terrestrial protected areas. The two main shortcomings of using a scoring approach (discussed in Keppel (2014) [1]) that are resolved with decision science approaches (presented in Klein et al. (2014) [2]) in Fiji were (1) priorities did not achieve one of the most important stated conservation goals of representing ~40% of Fiji׳s major vegetation types and (2) the weighting of different selection criteria used was arbitrary. Both approaches considered expert knowledge and land–sea connections important to decision makers in Fiji, but only decision science can logically integrate both, in addition to other important considerations. Thus, decision makers are urged to use decision science and avoid additive scoring systems when prioritizing places for conservation. Fiji has the opportunity to be a global leader in using decision science to support integrated land–sea planning decisions.  相似文献   
957.
The United Nations General Assembly in 2006 and 2009 adopted resolutions that call for the identification and protection of vulnerable marine ecosystems (VMEs) from significant adverse impacts of bottom fishing. While general criteria have been produced, there are no guidelines or protocols that elaborate on the process from initial identification through to the protection of VMEs. Here, based upon an expert review of existing practices, a 10-step framework is proposed: (1) Comparatively assess potential VME indicator taxa and habitats in a region; (2) determine VME thresholds; (3) consider areas already known for their ecological importance; (4) compile information on the distributions of likely VME taxa and habitats, as well as related environmental data; (5) develop predictive distribution models for VME indicator taxa and habitats; (6) compile known or likely fishing impacts; (7) produce a predicted VME naturalness distribution (areas of low cumulative impacts); (8) identify areas of higher value to user groups; (9) conduct management strategy evaluations to produce trade-off scenarios; (10) review and re-iterate, until spatial management scenarios are developed that fulfil international obligations and regional conservation and management objectives. To date, regional progress has been piecemeal and incremental. The proposed 10-step framework combines these various experiences into a systematic approach.  相似文献   
958.
‘Offshore CO2 storage’ refers to the injection of liquefied CO2 into deep geological formations beneath the seabed (e.g. depleted oil and gas reservoirs, and saline aquifers) for the purpose of storing it there on a permanent basis. The storage in this manner of captured CO2 emissions from industrial installations and power plants has attracted considerable scientific and technical interest as a potential mitigation response to climate change. A key issue facing policymakers in several countries is how to reconcile policy commitments to develop offshore CO2 storage with other competing – and potentially conflicting – uses of the marine environment. With a view to informing policy responses to this issue, this paper presents a case study of legal and policy frameworks concerning offshore CO2 storage in United Kingdom. The paper maps key design features of the United Kingdom׳s framework for marine permitting and planning, appraising the extent to which they enable orderly development of offshore CO2 storage in a manner consistent with relevant high-level policy objectives.  相似文献   
959.
This paper investigates the extent to which remote sensing data can contribute to the management of two parallel crises in the South China Sea (SCS); first the ongoing disputes related to islands and related maritime boundaries and second the degradation of the marine environment and the decrease in fish stocks. It demonstrates that remote sensing surveys are the only means to lawfully collect independent and verifiable geographic data on the disputed features without the need to consult all the claimants and thereby add to regional frictions and tensions. These surveys can contribute to the determination of whether these features are submerged or above water at high tide and what their physical characteristics are. This would inform the application of the Law of the Sea and help determine entitlements to maritime zones and thus access to resources. The other category of uses for remote sensing surveys which is explored is the identification and classification of marine habitats and the building of a biogeographic platform. This paper shows the limits created by unavoidable uncertainties in the interpretation of satellite imagery. However, many benefits outweigh the downsides: the potential for national and regional marine spatial planning, for the prioritization of marine environments in need of management, for the implementation by the States bordering the SCS of the international treaties which they have ratified and for ecological monitoring.  相似文献   
960.
Taiwan has disadvantageous conditions for sediment-related disasters such as debris flows. The construction of engineering structures is an effective strategy for reducing debris flow disasters. However, it is impossible to construct engineering structures in all debris flow areas in a short period. Therefore, the government aims to gradually develop non-structural preventive strategies, including evacuation planning, debris flow disaster emergency action system, disaster resistant community program, recruitment of debris flow professional volunteers, debris flow warning systems, and land management strategies, to mitigate disasters and secure the safety of residents. This review describes the processes and effects of recent debris flow non-structural preventive strategies in Taiwan. The average number of casualties prior to the year 2000 was far higher than the corresponding number after 2000 because debris flow evacuation drills have been promoted since 2000 and the debris flow disaster emergency action system has been progressively improved since 2002. Furthermore, the changes in risks caused by debris flow disasters before and after the implementation of non-structural preventive strategies were used to explain the effectiveness of these strategies at the community level. The results showed that software-based non-structural preventive strategies can effectively reduce the casualties caused by debris flows at both the national and community levels.  相似文献   
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