Nutrition-addition effect
The values of nutrition-addition effect were higher than zero except the one on S. grandis in mixture with L. chinensis . The nutrition-addition effect was significantly influenced by the effects of target species, plantation condition and their interaction. RegardingS. grandis , the nutrition-addition effect was lower in mixture with L. chinensis than grown in any of the other plantation conditions. As for S. krylovii , the nutrition-addition effect was relatively lower in mixture with L. chinensis or A. cristatum than in any of the other two conditions. Compared with the mean value of S. grandis in the same plantation conditions, the nutrition-addition effect of S. krylovii was relatively lower in mixture with A. cristatum but was relatively higher in any of the other three plantation conditions (Fig. 4).