Abstract:

In order to provide better understanding and studying on soil moisture forecast methods, according to the soil moisture and meteorological data of 2009-2010 in Hengyang City, soil moisture forecast models were built and validated based on previous precipitation and evaporation. Research showed that soil moisture forecast line regression model was built based on the difference between precipitation by 1mm and evaporation and stepwise regression model was built based on precipitation by 1 mm, the difference between precipitation by 1 mm and evaporation, the soil moisture in 8-12 months of 2009 was predicted. The average forecast error for soil layer 0-10 cm, 10-20 cm and 20-30 cm was 10.06%, 5.56% and 7.14%, respectively by line regression model. The average forecast error for soil layer 0-10 cm, 10-20 cm and 20-30 cm was 10.05%, 5.59% and 6.85%, respectively by stepwise regression model. The results for the soil moisture forecasted by 2 models revealed the developing tendency of the drought in Hengyang City. The models can predict the change of soil moisture accurately, that provide references for carrying out meteorological services for farmers and disaster prevention and mitigation.