Abstract: Mathematical model is an important tool for the planning and design of vegetative filter strips (VFS). Through the analysis on the purification mechanisms of VFS to suspended solids in surface runoff, a mathematical model which coupled the field scale mechanism model VFSMOD and the revised soil erosion model MUSLE was designed to simulate the purification effect of VFS on the suspended solids in surface runoff. The applicability and performance ability of this coupling model were validated by field plot experiment. The results showed that the relative deviations between the simulated and measured values of the concentrations of suspended solids were within ±20%, and the determination coefficients between the simulated and measured values were 0.98, suggesting that this coupling model had a high precision and was superior to VFSMOD model, being able to be used as a tool for the planning and design of VFS in China.  

Key words: arsenite, aging, combined As., available As