| 2. |
- Jordi, C, et al.
(författare)
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The design and performance of the Gaia photometric system
- 2006
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Ingår i: Monthly Notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 1365-2966 .- 0035-8711. ; 367:1, s. 290-314
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Tidskriftsartikel (refereegranskat)abstract
- The European Gaia astrometry mission is due for launch in 2011. Gaia will rely on the proven principles of the ESA Hipparcos mission to create an all-sky survey of about one billion stars throughout our Galaxy and beyond, by observing all objects down to 20 mag. Through its massive measurement of stellar distances, motions and multicolour photometry, it will provide fundamental data necessary for unravelling the structure, formation and evolution of the Galaxy. This paper presents the design and performance of the broad- and medium-band set of photometric filters adopted as the baseline for Gaia. The 19 selected passbands (extending from the UV to the far-red), the criteria and the methodology on which this choice has been based are discussed in detail. We analyse the photometric capabilities for characterizing the luminosity, temperature, gravity and chemical composition of stars. We also discuss the automatic determination of these physical parameters for the large number of observations involved, for objects located throughout the entire Hertzsprung-Russell diagram. Finally, the capability of the photometric system (PS) to deal with the main Gaia science case is outlined.
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| 3. |
- Fabricius, C, et al.
(författare)
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Powerless spectators, coping actors, and adaptive co-managers: a synthesis of the role of communities in ecosystem management
- 2007
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Ingår i: Ecology and Society. - 1708-3087. ; 12:1, s. 29-
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Tidskriftsartikel (refereegranskat)abstract
- We provide a synthesis of the papers in the Special Issue, the Communities Ecosystems and Livelihoods component of the Millennium Ecosystem Assessment (MA), and other recent publications on the adaptive capacity of communities and their role in ecosystem management. Communities adapt because they face enormous challenges due to policies, conflicts, demographic factors, ecological change, and changes in their livelihood options, but the appropriateness of their responses varies. Based on our synthesis, three broad categories of adaptive communities are identified. “Powerless spectator” communities have a low adaptive capacity and weak capacity to govern, do not have financial or technological options, and lack natural resources, skills, institutions, and networks. “Coping actor” communities have the capacity to adapt, but are not managing social–ecological systems. They lack the capacity for governance because of lack of leadership, of vision, and of motivation, and their responses are typically short term. “Adaptive manager” communities have both adaptive capacity and governance capacity to sustain and internalize this adaptation. They invest in the long-term management of ecosystem services. Such communities are not only aware of the threats, but also take appropriate action for long-term sustainability. Adaptive co-management becomes possible through leadership and vision, the formation of knowledge networks, the existence or development of polycentric institutions, the establishment and maintenance of links between culture and management, the existence of enabling policies, and high levels of motivation in all role players. Adaptive co-managers are empowered, but empowerment is a consequence of the capacity for governance and the capacity to adapt, rather than a starting point. Communities that are able to enhance their adaptive capacity can deal with challenges such as conflicts, make difficult trade-offs between their short- and long-term well-being, and implement rules for ecosystem management. This improves the capacity of the ecosystem to continue providing services.
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