Evaluating the effects of height and canopy of vegetative buffer strips on sediment transport reduction

Soil erosion is one of the most serious environmental issues in the world. Vegetative buffer strips include a specific plant being passed by flow before entering the waterways, so it causes to reduce runoff volume, deposited pesticides and other pollutants of the flow through infiltration, absorption and sediment deposition. The present study has been carried out with aim to investigate the effect of plant height and canopy on the efficiency of vegetative buffer strips to reduce sediment transport. This study was conducted using 1×10 experimental plots and producing artificial runoff with a discharge rate as much as precipitation with 100-year return period as well as two plant species of vetiver grass and native turf grass during one year in Lalim region of Sari, Mazandaran, Iran. The results indicated that, plant height and canopy which may be different in various time periods, have a considerable role in the efficiency of vegetative buffer strips to control sediment concentration. Also, it was found that the efficiency of vegetative buffer strips to reduce suspended sediment concentration of runoff is more affected by canopy and uniformity of plant density than plant height. In fact, increasing height in most of plants ultimately would cause to increase canopy and consequently the efficiency of vegetative buffer strips. Finally, it was suggested to do more studies on the other factors such as precipitation and soil moisture affecting the efficiency of vegetative buffer strips in order to improve understanding and effectiveness of vegetative buffer strips in water and soil conservation.