Simulation of Water Heat Transfer in Aerated Zone under Coupling Effect of Snow and Freeze-Thaw in Typical Black Earth Soil Region of Northeast China
The coupling effect of snow and freeze-thaw can change the distribution of water and heat in black soil,and therefore affect soil fertility.To explore the laws of water and heat transfer under snow and freeze-thaw conditions in typical black soil areas,taking Gongzhuling city of Jilin province as an example,based on field in-situ observation tests,water and heat transfer simulation in aeration zone under the coupling effect of snow freeze-thaw in typical black soil areas was carried out.The Morris's screening method was used to conduct parameter sensitivity analysis,and the effectst of dif-ferent external temperatures and snow cover scenarios on water transfer in black soil were simulated and analyzed.The results show that the snowmelt water in spring in the research area can increase the moisture content of black soil with a depth of more than 20 cm by about 12%;The model based on field observation has the best simulation effect on the soil layer of 60-80 cm;Residual soil mois-ture content in the five parameters of sensitivity analysis has the highest sensitivity,and its sensitiv-ity coefficient reaches 2.954 6;The external temperature affects the time when the soil moisture con-tent drops suddenly,and the snow cover conditions mainly affect the moisture content and water re-tention.
Northeast black soil regionsnow coverfreeze-thawwater and heat characteristicsHYDRUS-1D modelMorris's screening methodscenario simulation