Estimation of Root Zone Soil Moisture in a Small Forested Watershed Based on the SMAR Model
Root zone soil moisture(RZSM)plays an important role in hydrological simulation and agricultural man-agement.However,direct measurement of RZSM is very difficult.Estimating variations in RZSM is possible with Soil Moisture Analysis Relationships(SMAR).However,it is rarely assessed in regions with complex terrain.In this paper,soil moisture profiles at 32 sites in the Shale Hills,USA,were measured daily for a three-year period(2011 to 2014)to examine the accuracy of the physical mechanism-based SMAR model for RZSM estimations.Additionally,the method's efficiency was assessed in various spatial and temporal contexts.The results show that the SMAR model is able to accu-rately estimate RZSM using surface soil moisture(SSM)data.The mean RMSE of the simulation results was 0.034 compared with the measured data,indicating that the spatial distribution of rhizospheric soil moisture at the watershed scale could be well estimated.Temporally,the accuracy of the model is better in the wet and cold seasons than in the dry and warm seasons.This study increases the understanding of using SSM to simulate RZSM in complex terrain,which provides support for simulation of root zone soil moisture at condition of complex terrain.
soil moistureroot zoneSMAR modelspatial and temporal variability
NETL
NSTL
万方数据
维普
