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排序方式: 共有726条查询结果,搜索用时 139 毫秒
721.
Investigating Climate Change Impacts and Thresholds: An Application of the CLIMPACTS Integrated Assessment Model for New Zealand Agriculture 总被引:1,自引:0,他引:1
G. J. Kenny R. A. Warrick B. D. Campbell G. C. Sims M. Camilleri P. D. Jamieson N. D. Mitchell H. G. McPherson M. J. Salinger 《Climatic change》2000,46(1-2):91-113
The determination of `critical thresholds'is an essential task for informed policydecisions on establishing greenhouse gas emissiontargets. This paper presents a framework fordetermining critical thresholds for New Zealandagriculture, focusing on three agriculturalcrops – kiwifruit, grain maize, andPaspalum dilatatum – as exemplars for the fruitproduction, arable cropping and dairy productionindustries in New Zealand. The approach is based onthe application of a country-scale, integratedassessment model, called CLIMPACTS. The CLIMPACTSsystem contains a climate change scenario generator,climate and land data, and sectoral impact models. Importantly, CLIMPACTS allows time-dependentassessments of climate change and its effects, whichfacilitates the identification and examination of thresholds, which largely relate to spatial changes, over time, in regions of economic importance for these crops. However, whether such thresholds are `critical' for New Zealand cannot currently be addressed by the CLIMPACTS model. The determination of `criticality' requires a fully integrated assessment in which the social, economic, and environmental costs and risks associated with these thresholds are comprehensively evaluated. 相似文献
722.
723.
The Environment Act 1995 and quiet enjoyment: implications for countryside recreation in the national parks of England and Wales, UK 总被引:1,自引:0,他引:1
Summary National parks in England and Wales have traditionally been seen as places of quiet, less hurried recreation. The phrase 'quiet enjoyment' was adopted to represent this notion, and this paper traces the policy-making process involved in attempting to conserve this view. The debate during the enactment of the Environment Act 1995 brought the use and meaning of the phrase to prominence; amongst other issues, the use of the phrase in tenancy law precluded its use in legislation. The loss of the phrase 'quiet enjoyment' could have prolonged effects on the way in which national parks are used for recreational purposes. 相似文献
724.
725.
Information from an outcrop is used as an analogue of a natural heterogeneous aquifer in order to provide an exhaustive data set of hydraulic properties. Based on this data, two commonly used borehole based investigation methods are simulated numerically. For a scenario of sparse sampling of the aquifer, the process of regionalization of the borehole hydraulic conductivity values is simulated by application of a deterministic interpolation approach and conditioned stochastic simulations. Comparison of the cumulative distributions of particle arrival times illustrates the effects of the sparse sampling, the properties of the individual investigation methods and the regionalization methods on the ability to predict flow and transport behaviour in the real system (i.e. the exhaustive data set). 相似文献
726.
Ian A. Simpson Sophia Perdikaris Gordon Cook John L. Campbell William J. Teesdale 《Geoarchaeology》2000,15(8):743-763
The development of specialized and commercial fishing activity in the island archipelago of Lofoten and Vesterålen in northern Norway is a critical foundation from which to understand the subsequent spread of commercial fishing across the north Atlantic region during the medieval and early modern period. One little understood aspect of this development is the relationship between medieval commercial fishing stations (fiskevaer) and earlier fishing activity. In this article, cultural sediment deposits at Langenesværet, Vesterålen, Northern Norway provide an opportunity to examine this relationship and its implications for current historical models of fishing development in northern Norway and the north Atlantic region. Conventional and AMS radiocarbon dating techniques are used to establish a chronology for the deposits, while activities associated with the sediments are characterized using thin‐section micromorphology supported by proton induced X‐ray emission spectrometry (PIXE). The results suggest that the site commenced formation as early as ca. 3000 B.C. and that the site was first used for specialized fishing activity from the early centuries A.D. The medieval commercial fiskevaer settlement at Langenesværet was introduced to an area that had a longstanding tradition of specialised fishing activity. © 2000 John Wiley & Sons, Inc. 相似文献