• Journal of Ecology and Environment
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• 제35권4호
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• pp.323-329
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• 2012

The Standardized Precipitation Index (SPI) is a widely used drought index to provide good estimations of the intensity, magnitude and spatial extent of droughts. The objective of this study was to analyze the spatial pattern of drought by SPI index. In this paper, the patterns of drought hazard in Iran are evaluated according to the data of 40 weather stations during 1967-2009. The influenced zone of each station was specified by the Thiessen method. It was attempted to make a new model of drought hazard using GIS. Three criteria for drought were studied and considered to define areas of vulnerability. Drought hazard criteria used in the present model included: maximum severity of drought in the period, trend of drought, and the maximum number of sequential arid years. Each of the vulnerability indicators were mapped and these as well as a final hazard map were classified into 5 hazard classes of drought: one, slight, moderate, severe and very severe. The final drought vulnerability map was prepared by overlaying three criteria maps in a GIS, and the final hazard classes were defined on the basis of hazard scores, which were determined according to the means of the main indicators. The final vulnerability map shows that severe hazard areas (43% of the country) which are observed in the west and eastern parts of country are much more widespread than areas under other hazard classes. Overall, approximately half of the country was determined to be under severe and very severe hazard classes for drought.

• 한국환경과학회지
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• 제29권11호
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• pp.1099-1108
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• 2020

In this study, the capacity of supplying agricultural water to 13 districts was analyzed by calculating the necessary water supply for the arable land of Gunwi-gun and examining the capacity of supplying water to reservoirs, streams, pumping stations, collection sites, and groundwater wells in Gunwi-gun. As a result, among the 13 districts the second district was found to be short of water by 1.2×10⁶ tons/year. In general, local governments establish drought measures by selecting drought disaster risk zones. While selecting drought-risk areas, some water-poor areas that do not have water sources should be selected, even if the entire area has a sufficient water supply. The water-supply evaluation at the regional level was insufficient for locating areas without water sources, but most areas with water sources, such as streams, reservoirs, and pumping stations, were found to have no shortage of water. To locate water shortage areas without water sources, GIS analysis conducted a field survey of areas with a distance of 4 or less than that of water sources analyzed by GIS analysis. Sixty-nine sites in 13 districts were selected for the on-site survey and six areas of water shortage were identified in areas other than the second district.