Document Type : Research Paper
Authors
1 MSc, Faculty of Human Science, Najafabad Unit, Islamic Azad University, Iran
2 Associate Professor, Watershed Management Research Department, Isfahan Agricultural and Natural Resources Research and Education Center, AREEO, Isfahan, Iran
3 Assistant Professor, Faculty of Geographical Sciences and Planning, University of Isfahan
Abstract
Among the widespread studies have made on drought, rangelands drought has just received little attention. This study investigates the effect of drought on rangelands of Isfahan province. For this, Standardized Precipitation Index (SPI), Rainfall Anomally Index(RAI), Percentage of difference between the measured rainfall and Statistical Index Annual Precipitation(SIAP) were assessed in different time periods and their relation with these type of rangelands production in Isfahan province were studied. In this study, the monthly precipitation data in Esfahan, Meyme and Shahreza stations and forage production data in Charmshahr, Moote, Gardaneshadian rangelands in the period 1998-2007 were used. To investigate the relationship between indices and pastures production, the Pearson correlation was used. The results showed that only in Moote pasture, there were significant relationship and in the other pastures due to the special conditions, there was no correlation between these two variables The results indicate that effect of time periods were more than effect of indexes and spring rains have the greatest effect on the production of rangelands with Artemisia sieberi type in Isfahan province. Finally, the percentage of difference between rainfall in the range 3 month with 0.867 and then RAI 3 with 0.863 and SPI 3 with 0.802 were determined as the most appropriate index of drought.
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