The tenth IMSC, Beijing, China, 2007 - International Meetings on ...

disturbance in the natural ecosystems. Droughts are the symbols of climatic changes and are
accounting as natural damages affecting the human life and ther living creatures.
In this study climatological drought at the Aji-chai basin was studied using SPI index. For
this propose climatalogical data of the selected stations (Tabriz, Ahar, Sarab, Bostanabad
Ligvan) were used to study drought conditions for 3, 6 and 12 months time periods, the results
shows that drought are appearing in the short time periods with short time duration but
longtime droughts are also have the longtime durations.
In the Aji-chai basin the number of short time droughts are more than longtime. Ones in
which duration of the longtime droughts comparing with short time droughts are more. All of
the selected stations are facing to 3, 6 and 12 months gentle to moderate droughts and there
are no intensive or very intensive drought in the studied stations.
Keywords: Drought, Ajichai, SPI, GIS.
<strong>The</strong> quantitative survey of drought effects on the barley yield in Eastern Azarbayjan by classical
statistical ways
Speaker: Elham Rahmani
Elham Rahmani
Tehran University
Elhamrahmani1382@yahoo.com
Abdolmajid Liaghat
Tehran University
Ali Khalili
Tehran University
<strong>The</strong> growing season climatic parameters; especially, rainfall plays the main role to
predict the yield production. <strong>The</strong>refore the main objective of this research was to find out some
possible relations among meteorology parameters and drought indexes with the yield using
classical statistical methods.
To achieve the objective, meteorological parameters such as; precipitation, the average of
maximum temperature, the average of minimum temperature, the average of temperature, the
sum of temperatures more than 10º,evaporation,the water vapor pressure ,the average of wind
speed, the sunshine .and the drought indexes such as; Percent of normal Index, Standard
Index of Annual Precipitation Index, Hydrothermal Index, Nguyen Index, Transeau Index,
Standardized Precipitation Index, Shashko moisture drought Index, Rainfall Anomaly Index
were evaluated in terms of normality and their mutual influences. <strong>The</strong>n the correlation analysis
between the barley yield and the climatic parameters and drought indexes have been
examined .the results of this study showed that among the drought indexes, Nguyen Index ,
Transeau Index , Rainfall Anomaly Index and Standardized Precipitation Index (SPI24) are
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