Nutrition-addition measurements
Similar to the index of competition intensity, we quantified the
nutrition-addition effect with LnRR:
\begin{equation}
Nutrition-addition\ effect=ln\frac{\text{Biomass}_{h\text{igh\ nutrition}}\ }{\text{Biomass}_{\text{low\ nutrition}}}\nonumber \\
\end{equation}Where \(\text{Biomass}_{\text{high\ nutrition}}\) is the biomass of the
target species (S. grandis or S. krylovii ) grown under
high nutrition treatment, and \(\text{Biomass}_{\text{low\ nutrition}}\)is the average biomass of the target species (S. grandis orS. krylovii ) grown under low nutrition treatment. The
nutrition-addition effect was calculated within each target species (2)
and plantation condition (4) cross-treatment, respectively.