Mapping of heat stress using Geographic Information Systems (Case study: Effective thermal thresholds of Wheat in Fars Province)

Temperature is one of the most important climate parameters affecting yield production. In the present study, the critical threshold of heat stress for wheat cultivation in Fars Province was evaluated and the equations for each critical threshold is presented. For this purpose, 14 active stations of Fars Province were selected. According to the climatic conditions of the region, three thresholds of temperature of 30, 35 and 40 degrees Celsius were selected and the days when the maximum daily temperature was higher than these thresholds were studied. Also, due to the importance of heat stress at night, the number of days when the air temperature was at least 20 degrees Celsius was also determined. Finally, according to the results, the mapping of thermal stresses in Fars Province was presented .The evaluation results showed that the southern part of Fars Province consists mainly Larestan, Mohr and Khonj and northwestern parts including Kazeroon and Mamasani are more susceptible to heat stress and larestan and mamasani more than other areas suffer from stress. In most cases, periods of heat stress coincide during germination and flowering of wheat culture in Fars Province. Maps provided by climatological analysis helps to agriculture managers to estimate probability of favorable or unfavorable atmospheric events in later stages of crop development with high accuracy.