Abstract

In this study, the contribution weight of soil and water conservation effect of forest canopy layer and grass layer were calculated and analyzed using the measured data of soil loss (SL) and surface runoff depth (RD) in 12 experimental plots in Changting County, Fujian Province, China. Results indicate that the average SL and RD followed the order: pure tree > pure grass > tree-grass. Either SL or RD did not present a simple addition relationship among the three kinds of vegetated plots, especially for RD, thereby exhibiting the interaction effects between tree canopy and grass layers. The weight coefficients to soil and water conservation followed the order: grass > tree canopy > interaction between tree and grass, with 0.40, 0.35, and 0.25 for soil conservation, and 0.76, 0.14, and 0.10 for water conservation, respectively. The structured leaf area index (LAI) calculated with the weighted addition of LAIs of tree and grass correlated better with soil and water conservation effects than with overall and layered LAIs. The contribution weights in the construction of structured vegetation parameters can be applied for soil and water conservation.