Effect of intraspecific competition on biomass partitioning of Larix principis-rupprechtii

It is acknowledged that trees biomass allocation in response to environmental conditions. However, it remains poorly understood what strategies of plant biomass allocation with inter- and intraspecific interactions of tree species in forest stands. Such information is important for revealing strategies of plant biomass allocation with plant competition. To address this problem, a study was conducted in Larix principis-rupprechtii plantations to evaluate the impact of plant competition on plant biomass allocation in Shanxi Province, China. We measured a competition index (CI), stem, branch, foliage, and root biomass as well as element content (Carbon (C), Nitrogen (N), Phosphorus (P), Potassium (K)). Stem-foliage ratio (S/F), aboveground–belowground biomass ratio (T/R), average annual increment of biomass (AAB), height (AAH), and DBH (AAD) were calculated. The study found that the competition intensity of neighboring trees was closely related to the partitioning of biomass. Our results demonstrated that competition pressure of neighboring trees was a crucial factor to drive and regulate the distribution of biomass. Predicting biomass allocation–competition relationships could represent a supportive method for improving management of Larix principis-rupprechtii plantations in Mountain Taiyue areas.