Effects of gaps on regeneration of woody plants：a meta-analysis

• Published in: Journal of forestry research Vol. 25; no. 3; pp. 501 - 510
• Main Authors: Zhu, Jiaojun, Lu, Deliang, Zhang, Weidong
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer-Verlag 2014; Northeast Forestry University; State Key Laboratory of Forest and Soil Ecology, Qingyuan Experi-mental Station of Forest Ecology, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang 110016, China
• Subjects: Biomedical and Life Sciences; canopy gaps; death; environmental factors; forest growth; forest litter; forest management; forest plantations; forest regeneration; forest types; Forestry; Life Sciences; meta-analysis; Meta分析; Review Article; shade tolerance; temperature; trees; understory; woody plants; 密度表; 木本植物; 森林经营; 植物再生; 植物耐荫性; 生长周期; 间隙尺寸; disturbance; forest gap; shade tolerance; regeneration; gap size; gap age
• ISSN: 1007-662X; 1993-0607
• DOI: 10.1007/s11676-014-0489-3

Forest gaps, openings in the canopy caused by death of one or more trees, have a profound effect on forest regeneration and drive the forest growth cycle. It is therefore necessary to understand the effects of forest gaps on regeneration for modern forest management. In order to provide a quantitative assessment of the effects of forest gaps on regen-eration of woody plants, we conducted this review of gap effects on woody plant regeneration on the basis of 527 observations from 42 indi-vidual papers, and reported the results of these data in a meta-analysis. Overall, densities of regenerated woody plants were significantly greater （359%） in forest gaps than on the closed-canopy forest floor. The regen-eration density in gaps of plantation forests was significantly greater （P＆lt;0.05） than that of natural forest because the regeneration in gaps of plan-tation forests was improved by both gap effects and experimental meas-ures. Similarly, in comparison to natural gaps, regeneration was better enhanced in artificial gaps. Regeneration density exhibited a significantly positive correlation with gap size, but a negative correlation with gap age because the gap size decreased with increasing gap age. Shade tolerance of woody plants affected regeneration density in gaps and understory. Average regeneration density of shade-tolerant species exhibited a sig-nificantly positive response to gaps but densities remained lower in total than those of intermediate and shade-intolerant species. Gap effects on regeneration decreased in response to increasing temperature and pre-cipitation because of the limiting effects of lower temperature and moisture on woody plant regeneration. In summary, forest gaps enhance woody plant regeneration, and the effects of gaps varied by forest type, gap characteristics, environmental factors and plant traits. The results of this meta-analysis are useful for better understanding the effects and roles of gaps on forest regeneration and forest management.