Investigation on slope and canopy closure effects to minimize sediment movement in riparian buffer zone

Abstract

In this study, factors affecting the width of buffer zone used to minimize the sediment movement in the productive forests, have been evaluated. For this purpose, sediment traps were constructed in Istanbul University Education Research and Practice Forest. Sediment data was obtained from sample plots established depending on the different canopy closure, slope length, slope area, rainfall and slope. In this context, a statistical model was developed to estimate the sediment yield depending on slope and canopy closure. The accuracy of the model was tested with various statistical analyses. According to the results, sediment value can be highly estimate depending on slope classes. According to results, in the developed regression models to estimate effects of slope percentage on sediment values, the smallest R2 value was found as 0.79 on 20 % slope area and the highest R2 value was found as 0.97 on 80 % and 100 % slope area. Also, as the slope increases, the accuracy of the regression model of sediment yield increases. And it is concluded that there is a very close relationship between 80 % and 100 % slope. In the developed regression models to estimate effects of canopy closure effects on sediment values, it is seen that the lowest R2 value was calculated on canopy closure 71-100 %, and the highest R2 values were calculated on canopy closure 41-70 % and cutting areas. Sediment yield increases with the decrease of the canopy closure and the accuracy of the model increases.