Effect of stand density and humus removal on regeneration of Pinus densiflora seedlings in a mixed conifer and broad-leaved forest

• Published in: Forestry Studies in China Vol. 14; no. 2; pp. 85 - 91
• Main Authors: Wu, Chu-ping, Ando, Makoto, Zhang, Jun, Shen, Ai-hua, Yuan, Wei-gao, Zhu, Jin-ru, Jiang, Bo
• Format: Journal Article
• Language: English
• Published: Heidelberg Beijing Forestry University 01.06.2012; Springer Nature B.V; Zhejiang Forestry Academy, Hangzhou 310023, P. R. China%Field Science Education and Research Center, Kyoto University, Kitashirakawa-oiwake, Kyoto 6068502, Japan
• Subjects: Biomedical and Life Sciences; Density; Forestry; Forestry Management; Forests; Humus; Life Sciences; Pine; Plant Ecology; Plant Genetics and Genomics; Regeneration; Research Article; Stands; Supports; Thinning; Tree Biology; Wood Science & Technology; 再生; 幼苗生长; 开度测量; 林分密度; 森林腐殖质; 赤松; 针阔混交林; 阔叶林; forest operation; thinning; regeneration; understory vegetation; Pinus densiflora
• ISSN: 1008-1321; 2095-4034; 1993-0372; 2197-5620
• DOI: 10.1007/s11632-012-0207-1

We studied the impact of stand density and forest floor humus removal on regeneration ofPinus densiflora in a mixed co- nifer and broad-leaved forest on the Daimonji-Yama Mountain, Kyoto, Japan. Three levels of stand density were set, i.e., a clear-cut site, a heavily thinned site and a lightly thinned site. In each density treatment, comparisons were carried out between humus removal （A0-free） and humus intact （A0-intact） subplots. We counted the emergence of sown pine seeds and measured survival and growth of pine seedlings over the next four years. In addition, light conditions and the recovery of understory were monitored. Results show that thinning intensity and humus removal promoted the establishment and growth of seedlings. One exception, however, was that seedling growth was minimal in the heavily thinned A0-intact subplots. This was due to a strong response of understory vegetation growth on the treatment combination, which hindered the pine seedling growth. Furthermore, we found that the canopy openness measured at 1.3-m height remained at least 35% for the heavily thinned site in 2008. The results suggest that the removal of the A0 layer after heavy thinning is the most effective and labor-saving operation for P. densifiora regeneration.