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31.
Carbonnier G 《Disasters》2006,30(4):402-416
The tendency today to privatise many activities hitherto considered the exclusive preserve of the state has given rise to sharp debate. The specific nature of humanitarian emergencies elucidates in particularly stark contrast some of the main challenges connected to the privatisation and outsourcing of essential public services, such as the provision of drinking water and health care. Privatising the realms of defence and security, which are at the very core of state prerogative, raises several legal and humanitarian concerns. This article focuses on the roles and responsibilities of the various parties involved in armed conflicts, especially those of private companies engaged in security, intelligence and interrogation work, and in the provision of water supply and health services. It highlights the need for humanitarian and development actors to grasp better the potential risks and opportunities related to privatisation and outsourcing with a view to supplying effective protection and assistance to communities affected by war. 相似文献
32.
33.
Southern Chile encompasses one of the most extensive fjord regions of the world, the Patagonia, currently exposed to natural
and anthropogenic perturbations. These fjord ecosystems provide important services to humans, which have not been adequately
measured and valued. As a consequence, ecosystem services are commonly ignored in public policy design and in the evaluation
of development projects. Here we tackle questions that are highly relevant for the nation’s development, namely (1) understanding
fjord functioning, and (2) developing management strategies based on ecosystem services, in order to secure simultaneous and
adequate use of these ecosystems which area influenced by ecological (e.g., biogeochemical) and productive (e.g., aquaculture,
fisheries) processes. We also seek to strengthen the analysis of fjord ecosystem value from the economical (including coastal
zoning), socio-cultural, institutional, and governmental points of view. In addition, the investigation of current and future
effects of climate change on this large region offers a unique opportunity to understand the social and economic consequences
of a global phenomenon at local to regional scales. Biogeochemical and socio-economic models will be used to simulate future
scenarios under a gamut of management options. 相似文献
34.
Jeffrey J. Opperman Ryan Luster Bruce A. McKenney Michael Roberts Amanda Wrona Meadows 《Journal of the American Water Resources Association》2010,46(2):211-226
Opperman, Jeffrey J., Ryan Luster, Bruce A. McKenney, Michael Roberts, and Amanda Wrona Meadows, 2010. Ecologically Functional Floodplains: Connectivity, Flow Regime, and Scale. Journal of the American Water Resources Association (JAWRA) 46(2):211-226. DOI: 10.1111/j.1752-1688.2010.00426.x Abstract: This paper proposes a conceptual model that captures key attributes of ecologically functional floodplains, encompassing three basic elements: (1) hydrologic connectivity between the river and the floodplain, (2) a variable hydrograph that reflects seasonal precipitation patterns and retains a range of both high and low flow events, and (3) sufficient spatial scale to encompass dynamic processes and for floodplain benefits to accrue to a meaningful level. Although floodplains support high levels of biodiversity and some of the most productive ecosystems on Earth, they are also among the most converted and threatened ecosystems and therefore have recently become the focus of conservation and restoration programs across the United States and globally. These efforts seek to conserve or restore complex, highly variable ecosystems and often must simultaneously address both land and water management. Thus, such efforts must overcome considerable scientific, technical, and socioeconomic challenges. In addition to proposing a scientific conceptual model, this paper also includes three case studies that illustrate methods for addressing these technical and socioeconomic challenges within projects that seek to promote ecologically functional floodplains through river-floodplain reconnection and/or restoration of key components of hydrological variability. 相似文献
35.
太湖湿地生态系统服务功能价值评估 总被引:11,自引:0,他引:11
随着生物资源价值估算方法的日益成熟,生态系统的服务评估成为生态系统研究的热点。运用市场价值、影子工程、碳税法等方法对太湖湿地生态系统的物质生产功能、环境调节功能和文化社会功能等直接与间接价值进行评估。结果表明:太湖湿地生态系统具有巨大和多重服务价值,总价值为112.39×108元。其中,生态环境调节与维护功能价值最大,占总服务价值的48.98%;其次是物质生产与供给功能,占29.1%;文化社会功能最小,占21.91%。通过对9项子功能进行评估得出,调蓄洪水的功能价值最大,约占26.23%,供水功能其次,约占24.56%,气候调节功能,约占18.23%,科研教育价值约占13.16%,植被资源生产功能价值最小,约占0.09%。此项研究首次定量评估了太湖湿地生态系统的服务功能价值,研究成果对于认识太湖湿地的价值,有针对性地保护太湖湿地具有现实意义。 相似文献
36.
Urban futures that are more resilient and sustainable require an integrated social–ecological system approach to urban policymaking, planning, management, and governance. In this article, we introduce the Urban Biodiversity and Ecosystem Services (URBES) and the Cities and Biodiversity Outlook (CBO) Projects as new social–ecological contributions to research and practice on emerging urban resilience and ecosystem services. We provide an overview of the projects and present global urbanization trends and their effects on ecosystems and biodiversity, as a context for new knowledge generated in the URBES case-study cities, including Berlin, New York, Rotterdam, Barcelona, and Stockholm. The cities represent contrasting urbanization trends and examples of emerging science–policy linkages for improving urban landscapes for human health and well-being. In addition, we highlight 10 key messages of the global CBO assessment as a knowledge platform for urban leaders to incorporate state-of-the-art science on URBES into decision-making for sustainable and resilient urban development. 相似文献
37.
Carbon Sequestration Function of Check-Dams: A Case Study of the Loess Plateau in China 总被引:2,自引:0,他引:2
Check-dams are the most common structures for controlling soil erosion in the Loess Plateau. However, the effect of check-dams on carbon sequestration, along with sediment transport and deposition, has not been assessed over large areas. In this study, we evaluated the carbon sequestration function of check-dams in the Loess Plateau. The results indicate that there were approximately 11 000 check-dams distributed in the Loess Plateau, with an estimate of the amount of sediment of 21 × 109 m3 and a soil organic carbon storage amount of 0.945 Pg. Our study reveals that check-dams in the Loess Plateau not only conserve soil and water but also sequester carbon. 相似文献
38.
Jacob Carstensen Daniel J. Conley Erik Bonsdorff Bo G. Gustafsson Susanna Hietanen Urzsula Janas Tom Jilbert Alexey Maximov Alf Norkko Joanna Norkko Daniel C. Reed Caroline P. Slomp Karen Timmermann Maren Voss 《Ambio》2014,43(1):26-36
Hypoxia has occurred intermittently over the Holocene in the Baltic Sea, but the recent expansion from less than 10 000 km2 before 1950 to >60 000 km2 since 2000 is mainly caused by enhanced nutrient inputs from land and atmosphere. With worsening hypoxia, the role of sediments changes from nitrogen removal to nitrogen release as ammonium. At present, denitrification in the water column and sediments is equally important. Phosphorus is currently buried in sediments mainly in organic form, with an additional contribution of reduced Fe-phosphate minerals in the deep anoxic basins. Upon the transition to oxic conditions, a significant proportion of the organic phosphorus will be remineralized, with the phosphorus then being bound to iron oxides. This iron-oxide bound phosphorus is readily released to the water column upon the onset of hypoxia again. Important ecosystems services carried out by the benthic fauna, including biogeochemical feedback-loops and biomass production, are also lost with hypoxia. The results provide quantitative knowledge of nutrient release and recycling processes under various environmental conditions in support of decision support tools underlying the Baltic Sea Action Plan. 相似文献
39.
基于不同价值构成的耕地资源价值评估——以湖南省为例 总被引:5,自引:0,他引:5
正确认识和科学评估耕地资源的完全价值,对缓解征地补偿标准过低、土地收益分配不合理以及粮食安全和生态环境等问题具有一定指导意义。基于耕地的不同价值构成,选用相应的评估方法对湖南省不同等级耕地的总价值进行了评估,评估结果为:1~5等耕地资源单位面积的总价值分别为547 24813、481 61077、430 74534、385 86049和336 19093元/hm2;不同等级耕地上3种耕地价值的构成不一样,社会保障价值在所有不同等级耕地总价值中所占比重最大。这一研究结论对于显化耕地资源的完全价值以及抑制耕地资源的过度流失具有积极的作用 相似文献
40.
Miyun County,located in the northeast of Chinese capital Beijing,was underwent remarkable variations in land use in recent years.This paper aimed to detect changes in land use of Miyun from 1997 to 2005,and to qualify the response of ecosystem to LUCC based on ecosystem services valuation.With two-periods TM images,we got land use change data,and then ecosystem services values were calculated using ecosystem services valuation coefficients proposed by Chinese scholar Xie Gaodi.Results showed that water area,farm land and unused land decreased while residential land,forest land,grassland and orchard land increased during the study period.The loss of ESV was RMB 206 million and the main reason was the decrease of water area and farm land area.As for spatial variation,there were most dramatically land use change and ESV decline in reservoir ecological protection region.The coefficient sensitivity analysis indicates that valuation coefficients used in the study are suitable and results are reasonable.The driving forces of ESV loss were rapid population growth and economic development.More work should be done to make eco-environment stay healthy. 相似文献