Abstract:Coastal soil was taken as an object in order to clarify the influence of straw coverage amount on soil evaporation resistance in Binhai area, and dynamic model of soil moisture evaporation and coverage resistance model under different straw coverage amount conditions (0kg/m2, 0.3kg/m2, 0.6kg/m2, 0.9kg/m2 and 1.2kg/m2, expressed as CK, S1, S2, S3, S4,respectively) were established, moreover, the measured and calculated evaporation data were evaluated. Results showed that the surface soil moisture was decreased exponentially with time, and the more amount of straw coverage, the higher surface soil moisture; both the soil evaporation rate and cumulative soil evaporation were increased exponentially with the increase of soil moisture. The decrease of soil moisture showed a linear increase trend with time, the determination coefficient R2 of the fitted line was greater than 0.9, and both the average soil evaporation rate and cumulative soil evaporation amount were decreased with the increase of straw coverage quantity. Coverage resistance under different straw coverage treatment had a large difference, while the difference for coverage resistance in the same straw coverage treatment was small, and the coverage resistance was increased linearly with the increase of straw coverage amount, moreover, the relationship between coverage resistance and straw amount showed a significant positive correlation (R2=0.9114, p<0.05). The RMSE, MAE and NS between the simulated and the actual soil evaporation was 4.18×10-4mm/min, 3.85×10-5mm/min, and 0.90, respectively, and the slope k for the simulated and actual soil evaporation fitted line was 0.926, indicating that the calculated straw coverage resistance model can accurately estimate the soil evaporation under straw coverage conditions.
