Monthly changes of Irrigation Hydro module for agricultural crops of Hamedan

ABSTRACT: Recent droughts and uncontrolled using of groundwater sources have caused a severe drop in groundwater level in most plain of Iran including Hamadan plain and exposed this region with a new challenge of water restriction. For being compatible with water crisis, an accurate estimation of crop water requirement, gross irrigation requirement, Hydro module and volume of pumping the underground water seem essential and this issue is not possible without accurate estimation of irrigation efficiency in each plain of country. Therefore, several farms were selected in Asadabad plain of Hamedan, and according to the implemented under-pressure irrigation level, irrigated cultivation area, and type of irrigation method (Traditional or Modern), the irrigation efficiency was determined by questionnaire, field and farm research in several irrigation. Based on measuring, the average irrigation efficiency of under-pressure and surface systems was estimated 69.65 and 40.08 percent, respectively. Given that the under-pressure irrigation level was 10.4 percent and the remaining lands were under the surface irrigation, the average irrigation efficiency of these farms was determined43 Percent by weight method. Moreover, according to the cultivation pattern and cultivation area of different crops, the Hydro module rate was calculated for all months of year and its maximum rate was related to July and calculated 0.79 liters per second per hectare; this can be the basis of irrigation scheduling in irrigation projects.