An Agro-Climatic Zoning of dryland whea Based on the date of the first rainfall 10 mm In the cultivation season in Kermanshah

Climate is the most important factor that determines the type of crop to planting in each region. Due to the fact that the cultivation of dryland wheat is a priority in the province, this study was selected. In this study, climatic data of 6 synoptic stations (1989-2012) and 8 climatology stations (2008-2013) were used. Due to the date of the beginning of autumn rains, planting date was suggested for each region of the province. Then different types of probabilistic distributions were fitted to the planting date. The best statistical distribution was selected from the coefficient of determination and different growth stages of dryland wheat were determined. From the precipitation element, the required types of precipitation maps were extracted. Also from the temperature element, various temperature maps and temperature stresses were prepared. Finally, climatic zoning map of dry land wheat were extracted and from this map the areas with no potential of cultivation were omitted. The final map comprised four very good, good, medium and weak areas. And maps of zoning for 5 mm Precipitation revealed that very suitable area for cultivation of wheat was located in some parts of the Northwest, West and South west of Kermanshah province. And suitable areas, was in the Northwest, West, Southwest and medium areas was located in Southwest, West,Center, North, Northeast, and southeast, And weak areas are often located in center and northeast.