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91.
Christoph Görg 《Geoforum》2007,38(5):954-966
Governance has become an iridescent concept in recent years. The term is widely used in almost all social-science disciplines as well as in the political process. The intention of this paper is not so much to clarify these sometimes vague meanings but to highlight some characteristics of environmental governance connected with the restructuring of the spatial dimensions of politics. It starts from the assumption that the quest for multi-level decision making is particularly pressing for environmental governance. However, multi-level governance raises concern about the constitution of various spatial levels and their relationships with each other, as discussed under the term of “politics of scale”. Moreover, it is argued that for environmental governance the spatial reference is strongly connected with another challenge, which concerns the question of how to deal with the biophysical conditions of particular places. The term landscape governance is introduced to tackle this question without referring to an ontologically given space. Thus, landscape governance deals with the interconnections between socially constructed spaces (the politics of scale) and “natural” conditions of places. For this task, the concept of societal relationships with nature is introduced and applied to the term “landscape” as a bridging concept between social and natural sciences. The paper illustrates the approach of landscape governance with examples of problem-oriented interdisciplinary research at the UFZ-Centre for Environmental research in Leipzig, Germany. 相似文献
92.
Results from numerical investigations regarding the exchange of HNO3, NH3, and NH4NO3 between the atmosphere and the biosphere are presented. The investigations were performed with a modified inferential method which is based on the generally accepted micrometeorological ideas of the transfer of momentum, sensible heat and matter near the Earth's surface and the chemical reactions among these nitrogen compounds. This modified inferential method calculates the micrometeorological quantities (such as the friction velocity and the fluxes of sensible and latent heat), the height-invariant fluxes of the composed chemically conservative trace species with group concentrationsc
1=[HNO3]+[NH4NO3] (total nitrate),c
2=[NH3]+[NH4NO3] (total ammonia), andc
3=[HNO3]-[NH3] as well as the fluxes of the individual nitrogen compounds. The parameterization of the fluxes is based on the flux-gradient relationships in the turbulent region of the atmospheric surface layer. The modified inferential method requires only the data of wind velocity, temperature, humidity and concentrations (HNO3, NH3, and NH4NO3) measured at a reference height by stations of a monitoring network. 相似文献
93.
正确可靠的数据是GIS系统的核心。针对管网数据的复杂性,提出利用圈数据模型描述管网拓扑关系.并使用拓扑约束方法对管网数据一致性进行检测,以确保数据的正确性。该方法吸收了基于连接规则以及基于拓扑关系约束的方法的优点,能够更好的描述管网系统的整体结构并对其进行拓扑约束,使得一致性检测更加全面。 相似文献
94.
研究了概率赋范空间中D-有界集被零向量邻域吸收的性质。同时对各种有界性的关系也进行了研究。 相似文献
95.
In this paper we present magnitude (Ms) – magnitude(mb) and magnitude-intensity relationships which areconsidered the most adequate in the Ibero-Maghrebianregion. This work is based on selected samples ofrecently revised events with magnitude mb assigned bythe Instituto Geográfico Nacional (I.G.N.) and Msassigned by I.S.C and N.E.I.C., and isoseismal mapsfrom 142 events. Using these data, we have obtainedone magnitude (Ms) – magnitude (mb) relationship, twomagnitude (mb and Ms) assignment relationships viaepicentral intensity (I0), and ten magnitude (mb andMs) assignments relationships via macroseismicinformation: four using Ambraseys' methodology (1985)and six using the isoseismal area of degree III, IV and VI.According to the obtained results it could be concluded that historical magnitude assignment with lesser uncertainties are those obtained via macroseismic information using magnitude-intensity relationships with Ambraseys' methodology (1985). The magnitude-isoseismal area assignment relationships have, in most cases, great differences depending on the degree of the isoseismal area used. Magnitude assignments via epicentral intensity have the highest uncertainties. Geographic regionalization of the relationshipshas been studied but the highest correlations and statistical significance are obtained when we fit all the Ibero-Maghrebian region data.Finally we have used the results obtained in this workto assign magnitude to some important historicalearthquakes in the Ibero-Maghrebian region: the 1755Lisbon earthquake, the 1680 Málaga earthquake, the1829 Torrevieja earthquake and the 1884 Arenas del Reyearthquake. According to our relationships andmethodology we have assigned an Ms value of 9.3 ±0.6 to the 1755 Lisbon earthquake (its mb magnitudecannot be estimated due to the saturation of the mbscale), an mb value of 6.3 ±0.4 and an Ms valueof 6.9 ± 0.6 to the 1829 Torrevieja earthquake, anmb value of 6.2 ± 0.4 and an Ms value of 6.4 ±0.6 to the 1680 Málaga earthquake and an mb valueof 6.1 ± 0.4 and an Ms value of 6.5 ± 0.6 tothe 1884 Arenas del Rey earthquake. 相似文献
96.
利用中国地区435个台站1961—2002年逐日平均温度序列,将温度变化发生在9天时间尺度上的特征编码在网络中,通过研究二分图温度网络(BGT网络)中节点与项目的关系,揭示出9天时间尺度上温度变化的特征及其在空间上的拓扑统计性质.网络中各节点RRRD, RrDD, eeed, DRRD, DDRR等所代表的温度波动模态在网络中异常频发,对9天尺度温度变化的预报有一定的指导意义.统计网络的节点度分布,集群系数等拓扑结构特征量,发现BGT网络服从正态分布特征.BGT网络项目内节点度的多样性大体上 相似文献
97.
The binational cities of Dover and Calais and their region 总被引:2,自引:0,他引:2
Odile Heddebaut 《GeoJournal》2001,54(1):61-71
This paper analyses the question of cities that are localised at each part of an international border. We take as an example
the two cities of Dover and Calais and look at if they can be considered as binational cities, because they have been recently
connected by a tunnel, the ‘fixed link’, and because since 1993, the inner state borders of the European Union have disappeared.
It determines firstly if these two towns have been brought closer by the construction of the Channel tunnel and if specific
ties are linking these two towns. The article scrutinizes actions taken under INTERREG funds under the general framework of
the creation of the ‘Transmanche Region’ and its extension towards a Euroregion to sort out these two cities joint involvement.
Finally, it checks if this new area could lead to cross-border activity either for work or tourism and leisure purposes that
could conduct the cities of Dover and Calais toward a new type of relationship, premises of a binational city.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
98.
Particle manifold method (PMM) is a new extension of the numerical manifold method (NMM). PMM uses a mathematical cover system to describe the motion and deformation of a particle‐based physical domain. By introducing the concept of particle into NMM, PMM takes the advantages of easy topological and contact operations with particles. In this article, the methodology, formulations and implementation of the method are presented, together with modelling examples for validation. It is found that good solutions for both continuous and discontinuous problems are obtained by the new developed PMM. Due to the underlying coupled continuum‐discontinuum property of PMM, it has great potential for modelling of geomechanical problems. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
99.
100.
Marc H. Taylor Jorge Tam Vernica Blaskovic Pepe Espinoza R. Michael Balln Claudia Wosnitza-Mendo Juan Argüelles Erich Díaz Sara Purca Noemi Ochoa Patricia Ayn Elisa Goya Dimitri Gutirrez Luis Quipuzcoa Matthias Wolff 《Progress in Oceanography》2008,79(2-4):366
The Northern Humboldt Current Ecosystem is one of the most productive in the world in terms of fish production. Its location near to the equator permits strong upwelling under relatively low winds, thus creating optimal conditions for the development of plankton communities. These communities ultimately support abundant populations of grazing fish such as the Peruvian anchoveta, Engraulis ringens. The ecosystem is also subject to strong inter-annual environmental variability associated with the El Niño Southern Oscillation (ENSO), which has major effects on nutrient structure, primary production, and higher trophic levels. Here our objective is to model the contributions of several external drivers (i.e. reconstructed phytoplankton changes, fish immigration, and fishing rate) and internal control mechanisms (i.e. predator-prey) to ecosystem dynamics over an ENSO cycle. Steady-state models and time-series data from the Instituto del Mar del Perú (IMARPE) from 1995 to 2004 provide the base data for simulations conducted with the program Ecopath with Ecosim. In simulations all three external drivers contribute to ecosystem dynamics. Changes in phytoplankton quantity and composition (i.e. contribution of diatoms and dino- and silicoflagellates), as affected by upwelling intensity, were important in dynamics of the El Niño of 1997–98 and the subsequent 3 years. The expansion and immigration of mesopelagic fish populations during El Niño was important for dynamics in following years. Fishing rate changes were the most important of the three external drivers tested, helping to explain observed dynamics throughout the modeled period, and particularly during the post-El Niño period. Internal control settings show a mix of predator–prey control settings; however a “wasp-waist” control of the ecosystem by small pelagic fish is not supported. 相似文献