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Climate change impacts on irrigation water requirements in the Guadalquivir river basin in Spain 总被引:4,自引:0,他引:4
J. A. Rodríguez Díaz E. K. Weatherhead J. W. Knox E. Camacho 《Regional Environmental Change》2007,7(3):149-159
Irrigated production in the Guadalquivir river basin in Spain has grown significantly over the last decade. As a consequence,
water resources are under severe pressure, with an increasing deficit between available supplies and water demand. To conserve
supplies, the water authority has reduced the volume of water assigned to each irrigation district. Major infrastructural
investments have also been made to improve irrigation efficiency, including the adoption of high technology micro-irrigation
systems. Within a context of increasing water scarcity, climate change threatens to exacerbate the current supply-demand imbalance.
In this study, the impacts of climate change on irrigation water demand have been modelled and mapped. Using a combination
of crop and geographic information systems, maps showing the predicted spatial impacts of changes in agroclimate (climate
variables that determine the irrigation requirements) and irrigation need have been produced. The maps highlight a significant
predicted increase in aridity and irrigation need. Modelling of irrigation water requirements shows a typical increase of
between 15 and 20% in seasonal irrigation need by the 2050s, depending on location and cropping pattern, coupled with changes
in seasonal timing of demand. 相似文献
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Mostafa A. Shirazi 《Environmental management》1984,8(4):281-286
The biological effects of hazardous substances in the environment are influenced by climate, physiography, and biota. These factors interact to determine the transport and fate of chemicals, but are difficult to model accurately except for small areas with a large data base. The requirement for a large data base may be reduced locally if the regional influences of these factors were predetermined from existing data. Knowledge of the regional factors would also relax the restriction to considering only small areas. This paper advocates consideration of regional characteristics of the environment in the early stages of waste management strategy development. It presents as an example a procedure for selecting study sites from candidate-abandoned hazardous waste dumpsites in the southeastern United States. It uses small-scale maps of low resolution from the National Atlas to delineate the boundaries and to determine the environmental characteristics that prevail over units of land within the region. A computer map-overlay and graphic approach is used to facilitate the grouping of land types. Abandoned hazardous waste dumpsites found within land types that best represent the region are surveyed for selecting a study site. It is expected that environmental impact data obtained from a representative site would be useful for predicting impact potentials in similar remotely located areas within the same general region. 相似文献
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利用MapBasic编制震害评估软件时 ,无现成的工具直接绘制出长短轴不平行 (或不垂直 )于经纬度线的等烈度线。本文提出了一个通过椭圆旋转绘制出所要求的等烈度线椭圆的方法。 相似文献