Dynamic Effects of Structure-Based Forest Management on Stand Spatial Structure in a Platycladus orientalis Plantation

Abstract

Structure-based forest management (SBFM) is a method for improving forest structure and quality based on nearest-neighbor analysis. Stand spatial structure directly affects the health and stability of forest ecosystems. Research on the effects of SBFM on the distribution of spatial structure parameters is needed to provide a scientific basis for further development and implementation of SBFM technology in forestry. The present study was conducted on six permanent plots (20 m × 20 m) established within a Platycladus orientalis (L.) Franco plantation in Beijing, China. Changes in stand spatial structure parameters (SSSPs) were evaluated in managed and control plots at three time points: before SBFM and after 2 and 7 years of SBFM. The results showed that SBFM gradually accelerated the development of the P. orientalis plantation toward a random distribution pattern, reaching a significant difference within 2 years. SBFM promoted the growth of medium and dominant trees, with a significant difference between SBFM and control stands after 7 years. It led to a slight increase in mingling compared to the control, although no significant differences were observed between treatments. SBFM generally decreased the proportions of disadvantageous microstructures (disadvantaged trees with non-randomly distributed, disadvantaged trees with a low degree of mingling, and non-randomly distributed trees with a low degree of mingling). It also improved the ratio of torch (R2) units to dumbbell (R1) units, gradually improving the stability of the plantation forest. The results of this study suggest that SBFM optimized the spatial structure of a P. orientalis plantation in Beijing, China, and was conducive to tree growth and forest stand productivity.