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141.
Developing appropriate climate change adaptations to protect biodiversity requires taking into account the dynamics of agro-ecological and socio-economic change. A framework for approaching this problem was proposed, but not applied in detail, as part of a major biodiversity and climate change report prepared in Australia. This paper describes the first trial application of the method. It was applied across Vietnam as the Government is interested in identifying adaptation options and detailed data are readily available for its 65 provinces. The process involves identifying ecoregions and collating information for each region based on the current conditions and trends in biodiversity, population, income and agricultural production. Climate change scenarios are identified for each region, together with governance options. Educational needs and key adaptation actions are then identified for each region taking into account the agro-ecological and socio-economic input data. It is concluded that the framework could easily be applied in other countries and should assist the development of strategic adaptation options. 相似文献
142.
Long before the science of geology was established, the Derbyshire lead miners used elementary practical geology in laying out the lines of their soughs, or drainage levels, to gain any possible advantage of easier excavation. Their objective was to lower the water table, so as to make the deeper parts of mineral veins available for exploitation. 相似文献
143.
Combining GIS with neuro-fuzzy modeling has the advantage that expert scientific knowledge in coastal aquaculture activities can be incorporated into a geospatial model to classify areas particularly vulnerable to pollutants. Data on the physical environment and its suitability for aquaculture in an Irish fjard, which is host to a number of different aquaculture activities, were derived from a three-dimensional hydrodynamic and GIS models. Subsequent incorporation into environmental vulnerability models, based on neuro-fuzzy techniques, highlighted localities particularly vulnerable to aquaculture development.The models produced an overall classification accuracy of 85.71%, with a Kappa coefficient of agreement of 81%, and were sensitive to different input parameters. A statistical comparison between vulnerability scores and nitrogen concentrations in sediment associated with salmon cages showed good correlation.Neuro-fuzzy techniques within GIS modeling classify vulnerability of coastal regions appropriately and have a role in policy decisions for aquaculture site selection. 相似文献
144.
Hydrographic conditions, and particularly current speeds, have a strong influence on the management of fish cage culture. These hydrodynamic conditions can be used to predict particle movement within the water column and the results used to optimise environmental conditions for effective site selection, setting of environmental quality standards, waste dispersion, and potential disease transfer. To this end, a 3D hydrodynamic model, MOHID, has been coupled to a particle tracking model to study the effects of mean current speed, quiescent water periods and bulk water circulation in Mulroy Bay, Co. Donegal Ireland, an Irish fjard (shallow fjordic system) important to the aquaculture industry. A Lagangrian method simulated the instantaneous release of “particles” emulating discharge from finfish cages to show the behaviour of waste in terms of water circulation and water exchange. The 3D spatial models were used to identify areas of mixed and stratified water using a version of the Simpson-Hunter criteria, and to use this in conjunction with models of current flow for appropriate site selection for salmon aquaculture.The modelled outcomes for stratification were in good agreement with the direct measurements of water column stratification based on observed density profiles. Calculations of the Simpson-Hunter tidal parameter indicated that most of Mulroy Bay was potentially stratified with a well mixed region over the shallow channels where the water is faster flowing. The fjard was characterised by areas of both very low and high mean current speeds, with some areas having long periods of quiescent water. The residual current and the particle tracking animations created through the models revealed an anticlockwise eddy that may influence waste dispersion and potential for disease transfer, among salmon cages and which ensures that the retention time of waste substances from cages is extended.The hydrodynamic model results were incorporated into the ArcViewTM GIS system for visualisation and interrogation of results and to allow effective holistic environmental management and site selection for fish cage aquaculture. 相似文献
145.
The concept of human terrain has become a prominent element of U.S. military strategy. It is a means to capture the cultural–geographical qualities of an enemy or target population. An early effort to map human terrain is found in the Joint Army–Navy Intelligence Study (JANIS) of Korea (1945). We argue that the JANIS report on Korea was paradigmatic for the U.S. military's contemporary geographical work and offers insights into the cultural politics of human terrain mapping. This explains why the JANIS text is cited by the National Geospatial-Intelligence College (NGC) today as an historical model. This article not only offers a window into the history of geography counterinsurgent but also shows that geography has been entwined with empire. 相似文献
146.
147.
Trevor W. Marshall 《Astrophysics and Space Science》2012,342(2):329-332
The contemporary notion of black hole originates in Oppenheimer and Snyder’s 1939 article “On Continued Gravitational Contraction” (Phys. Rev. 56:455, 1939). In particular, Penrose (Phys. Rev. Lett. 14:57, 1965) showed that their metric gave rise to trapped surfaces, that is regions of space from which no light rays can escape, and proved that within such surfaces black-hole formation is inevitable. Section “No trapped surfaces” of this article shows that a simple modification of the Oppenheimer-Snyder metric, fully consistent with General Relativity, may be made, so that all radial light rays originating in the interior escape to the exterior. There is no trapped surface and no black hole; on the contrary there is a stable end state with finite density, contained within a sphere of Schwarzschild radius. Implications for the interpretation of General Relativity, and also for experimental observation of supermassive objects and the Event Horizon Telescope project, are discussed in the concluding section. 相似文献
148.
Abstract– The rock record from the early solar system indicates high‐temperature thermal processing sufficient to melt refractory oxides and silicates. The astrophysical context for the formation and evolution of our solar system, from a molecular cloud to a “clean” planetary system, is difficult to constrain tightly because of the large scales and lack of resolution of astronomical observations. Protostellar jets and winds, commonly associated with forming stars, are likely to play a role in heating and redistribution of the processed material in the solar system. We have recently proposed that disk‐winds can cause melting of small inclusions to distances out to several AU. Particularly energetic outbursts, such as the FU‐Orionis and EXor events, occur over relatively short time scales (approximately 100 and 1 yr, respectively), and are probably events related to formation of the refractory solids present in primitive meteorites. 相似文献
149.
AbstractCollaborative governance applied to environmental issues is becoming more common, and evaluation of such efforts can provide useful information for multiple audiences. However, due to a variety of challenges, collaborative governance practitioners rarely evaluate the outcomes of collaboration and their contributions to these efforts. With these challenges in mind, the William D. Ruckelshaus Center designed an evaluation framework that can meet multiple parties’ objectives, be integrated into practitioners’ existing services, and balance flexibility and practicality with rigor and replicability. The Center conducted a pilot of this framework on a collaborative watershed management effort in southeastern Washington State, where the Center had previously assisted with organizational development. The resulting evaluation highlights a variety of social, knowledge-based, and economic outcomes for the collaborative, as well as lessons for practitioners and evaluators of collaborative governance. We suggest that this methodology can be useful for practitioners interested in evaluating similar collaborative efforts. 相似文献
150.
Martin B. Kalinowski Anders Axelsson Marc Bean Xavier Blanchard Theodore W. Bowyer Guy Brachet Simon Hebel Justin I. McIntyre Jana Peters Christoph Pistner Maria Raith Anders Ringbom Paul R. J. Saey Clemens Schlosser Trevor J. Stocki Thomas Taffary R. Kurt Ungar 《Pure and Applied Geophysics》2010,167(4-5):517-539
A global monitoring system for atmospheric xenon radioactivity is being established as part of the International Monitoring System that will verify compliance with the Comprehensive Nuclear-Test-Ban Treaty (CTBT) once the treaty has entered into force. This paper studies isotopic activity ratios to support the interpretation of observed atmospheric concentrations of 135Xe, 133mXe, 133Xe and 131mXe. The goal is to distinguish nuclear explosion sources from civilian releases. Simulations of nuclear explosions and reactors, empirical data for both test and reactor releases as well as observations by measurement stations of the International Noble Gas Experiment (INGE) are used to provide a proof of concept for the isotopic ratio based method for source discrimination. 相似文献