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61.
62.
The Marine and Coastal Access Act 2009 is now enacted into law. This paper looks at predictions made about new law by one of the authors, Peter Jones, in his paper The Marine Bill: Cornucopia or Pandora's Box [1] and assesses how successful the Act has been in turning aspirations into law. The paper focuses on the following areas: ecosystem protection, stakeholder engagement, marine spatial planning and the provision of a network of highly protected marine reserves, and raises concerns that the ecosystem approach has progressively been dropped in the drafting process of the legislation. Concerns are raised that the new Inshore Fisheries and Conservation Authorities have similar inherent conflicts of interest to those exhibited by Sea Fisheries Committees, which they sought to replace. The effectiveness of marine planning is questioned, as there appear to be inbuilt loopholes for public authorities to avoid complying with the marine plans. The draft marine policy statement (MPS), published in July 2010, includes appropriate environmental safeguards, but the MPS has not yet been formally adopted. The absence of a concrete target for highly protected marine reserves means there is a danger that designations under the Act may have little effect on the ground. In conclusion the Act provides some new mechanisms for marine protection, but arguably does not yet provide a framework for implementing the ecosystem approach and is not an end in itself.  相似文献   
63.
Hydroelectric power is an important energy source to meet the growing demand for energy, and large amounts of water are consumed to generate this energy. Previous studies often assumed that the water footprint of hydroelectric power equaled the reservoir’s water footprint, but failed to allocate the reservoir water footprint among the many beneficiaries; dealing with this allocation remains a challenge. In this study, we developed a new approach to quantify the water footprint of hydroelectric power (WFh) by separating it from the reservoir water footprint (WF) using an allocation coefficient (ηh) based on the ratio of the benefits from hydroelectric power to the total ecosystem service benefits. We used this approach in a case study of the Three Gorges Reservoir, the world’s largest reservoir, which provides multiple ecosystem services. We found large differences between the WFh and the water footprint of per unit of hydroelectric production (PWFh) calculated using ηh and those calculated without this factor. From 2003 to 2012, ηh decreased sharply (from 0.76 in 2005 to 0.41 in 2012), which was due to the fact that large increases in the value of non-energy ecosystem services, and particularly flood control. In 2009, flood control replaced hydroelectricity as the largest ecosystem service of water from the Three Gorges Reservoir. Using our approach, WFh and PWFh averaged 331.0 × 106 m3 and 1.5 m3 GJ−1, respectively. However, these values would almost double without allocating water footprints among different reservoir ecosystem services. Thus, previous studies have overestimated the WFh and PWFh of reservoirs, especially for reservoirs that serve multiple purposes. Thus, the allocation coefficient should not be ignored when calculating the WF of a product or service.  相似文献   
64.
利用实地调研结果,结合相关文献资料,采用市场价值法、影子工程法、旅行费用法等评估方法,对溱湖湿地生态系统的物质生产、涵养水源和调蓄洪水、提供动植物栖息地、调节气候、降解污染物和科考旅游等6个效益最为突出的生态系统服务功能经济价值指标进行评估。研究表明:溱湖湿地生态系统的总价值为1.15×109元,其中直接使用价值为7.708×108元,间接使用价值为3.62×108元,非使用价值为0.18×108元。其中科考旅游价值所占比重最大,为40.84%,调节气候价值次之,而生物多样性保护价值仅占1.45%。对溱湖湿地生态系统服务功能及服务价值的探讨,可正确认识该生态系统的生态经济价值,为合理开发利用提供决策参考,确保其资源的可持续利用。  相似文献   
65.
The Helsinki Commission (HELCOM) Baltic Sea Action Plan, adopted by the coastal countries of the Baltic Sea and the European Community in November 2007, is a regional intergovernmental programme of measures for the protection and management of the marine environment explicitly based on the Ecosystem Approach. The Action Plan is structured around a set of Ecological Objectives used to define indicators and targets, including effect-based nutrient input ceilings, and to monitor implementation. The Action Plan strongly links Baltic marine environmental concerns to important socio-economic fields such as agriculture and fisheries and promotes cross-sectoral tools including marine spatial planning. Due to complementarities with the European Union (EU) Marine Strategy Framework Directive, the Action Plan is in essence a pilot for this process without neglecting the important role of the Russian Federation - the only Baltic coastal country not a member of the EU.  相似文献   
66.
以环渤海地区的天津滨海新区湿地为例,运用模糊综合评价模型对湿地生态系统的健康进行了诊断评价。首先从湿地生态特征、整体功能特征和社会经济3方面选取26个评价指标,构建了天津滨海新区湿地生态系统健康的评价体系。评价等级分为很健康、健康、一般、一般病态、疾病5级,运用定量与定性相结合的方法界定等级。运用模糊综合评价模型对天津滨海新区湿地生态系统健康进行诊断,评价综合得分为0.48,健康水平处于疾病状态,主要表现在水质污染严重和水源保证水平低、景观破碎化、功能退化3个方面。  相似文献   
67.
It is of great significance to analyze the long time-series spatiotemporal dynamics of water use efficiency (WUE) to formulating appropriate management measures in response to the growing water scarcity in arid and semi-arid regions. This study analyzed the long time-series variations of WUE in the Lower Heihe River Basin, a typical arid and semi-arid region in China. The net primary productivity (NPP) was first estimated with the C-fix model, then WUE during 2001–2010 was calculated with the NPP and evapotranspiration (ET) data, and the accumulative WUE was further calculated. The results showed that the annual NPP and WUE in the study area ranged from zero to 448.70 gC/(m2 a) and from zero to 2.20 gC kg−1 H2O, respectively, both of which showed an overall increasing trend during 2001–2010. Besides, the spatial pattern of WUE kept overall unchanged during 2001–2010, but with remarkable change in some part of the study area. In addition, the accumulative WUE of the whole study area showed a first sharply decreasing and then gradually increasing trend, but there was still some scope to improve the WUE, and it is necessary to carry out some more specific policies to further improve the water allocation and WUE within the Lower Heihe River Basin. Although with some uncertainties, these results still can provide valuable reference information for improving the water resource management and ecological conservation to guarantee provision of essential ecosystem services in arid and semi-arid regions.  相似文献   
68.
This study aims at determining the chlorine and chlorine-36 fallout rates in an experimental beech forest site located in NE France (48°31′55″ N, 5°16′8″ E). A monthly record of Cl and 36Cl concentrations in rainfall samples collected above the canopy was performed during two years, from March 2012 to February 2014. The results show that the Cl concentrations mainly originate from sea-spray while the 36Cl concentrations originate from the stratosphere and therefore present a seasonal dependency. Abrupt and important inputs of 36Cl from the stratosphere indeed yield sharp increases of the recorded concentrations during the spring-summer. We also show that a too short sampling period might bias the determined 36Cl fallout rate. To smooth the seasonal and sporadic bursts of 36Cl, a minimum of 6 months sampling period is required. A mean 36Cl fallout rate of (77 ± 21) atoms m−2 s−1 can be deduced from our study, which is 45% higher than the modelled value. This discrepancy suggests more studies aiming at measuring the 36Cl fallout rate worldwide are necessary.  相似文献   
69.
This paper examines the integration of landscape connectivity and ecosystem services. It is based on the assumption that if a habitat within a landscape has a more significant role in connecting with other habitats, it would have a higher ecosystem services value for biodiversity conservation. The Shenzhen River watershed, a cross-border region shared by the city of Shenzhen and the Hong Kong Special Administrative Region in China, was used as a case study. An area-based functional connectivity index, known as the possibility of connectivity (PC), was implemented to examine the temporal and spatial dynamics of the value of ecosystem services for biodiversity conservation over the period from 1988 to 2008. To evaluate the effectiveness of the PC index, a comparison was made between the conventional assessment method for ecosystem services and the proposed method. Results suggest that our proposed method can identify significant reduction of ecosystem services that was not only due to the decrease of habitat size, but also caused by the damage of connectivity among habitat patches. Also, it can identify sites which should have a high priority in restoring the ecosystem services for biodiversity conservation. In conclusion, this study provides a way to consider landscape connectivity in the evaluation of ecosystem services which is essential for landscape planning and nature conservation.  相似文献   
70.
Data resources and assessment frameworks are two keys to ecosystem health assessment (EHA). Application of the land use database together with the Pressure–State–Response (PSR) model in EHA provides better precision relative to traditional data resources and assessment frameworks for EHA at the county scale. The raw data are taken from The Anlu County Annals, The Soil Records of Anlu County, and The Statistical Yearbook of National Economy in Anlu County. The spatial and attribute data are partly extracted from the database of current land use in Anlu City using the MAPGIS platform. Based on the results from principal component analysis (PCA), a total of eleven indicators were selected to build an indicator system designed to assess the ecosystem health at the county scale. According to the PSR model, the scores from three indices (press index, state index, and response index) and a comprehensive assessment index (CAI) were calculated, and an assessment map was constructed. The results from the index scores and spatial analysis display a large range for the state of ecosystem health due to the evolution of natural ecosystems and human activities at the county scale. The precision of the current land use database (scale of 1:10,000) makes it a better candidate for evaluating ecosystem health than the traditional data resources. This study also demonstrates the numerous benefits of combining land use databases with GIS functions to assess ecosystem health at the county scale.  相似文献   
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