Evaluation of Rainfall Effect on Programing of Agricultural Management (Case Study: Golestan region)

Securing of water need in agricultural is important. Precipitation are one of the most important of water resources in agricultural, in Golestan province, especially, because Alborze mountains are in Golestan south. In research has investigated effects of rainfall to cropping pattern and intensification in Golestan farms. Rainfall used: a) have forecasted rainfalls by Minitab-13 program, b) Different probabilities of rainfalls by LST Program. Then estimated effective rainfall (by USDA method). For optimization used Lingo-8 program. Evaluations shown that in southern region (climate is: smi wet), if rainfall decreased, area of tomato and potato decreased, but canola area increased. In central and north regions (climates are: semi dried to dried), if rainfall decreased, watermelon area decreased, but canola area increased. Also if drought conditions, planting of canola, watermelon and cotton crops are important.