Demographic strategies of a dominant tree species in response to logging in a degraded subtropical forest in Southeast China

Abstract

& Key message The demography of pioneer tree species (Pinus massoniana Lamb.) is significantly affected by logging in Southeast China. Logging negatively affects the population growth rate of P. massoniana, which facilitates the growth of individual trees but has no effect on reproduction probability. The survival and growth of seedlings contribute the most to population growth. & Context Subtropical forest degradation caused by unreasonable disturbances is closely related to anthropogenic activities in Southeast China, and the frequent small-scale logging activity by local people was the dominated disturbance regime in forests in this region over the past several decades. & Aims The objective of this study is to evaluate the demographic consequences of logging on Pinus massoniana, a pioneer tree species, at individual level (survival, growth, and fecundity) and population level (the population growth rate and size distribution) over short-term period. & Methods The size of tree individuals was combined with vital rates using various modeling approaches based on demographic data from three annual censuses. The integral projection model (IPM) was constructed and used to conduct comparative demographic analyses. & Results Logging negatively affected the population growth rate: from a slight expansion before logging to a moderate decline after logging. This study found a significant reduction in seedling recruitment after logging, and plant growth and mortality were slightly enhanced. The survival of seedlings greatly contributes to population growth rate compared to other life stages for both periods (before and after logging) while its relative importance decreases after logging. Seedling growth is also important to population growth, and its relative importance increased after logging. Shrinkage and fecundity have a minimal contribution effect on the population growth rate. & Conclusion Growing plants in a nursery with a similar demography to P. massoniana could be beneficial for pioneer species regeneration in that this will improve the survival rate and growth of small individuals after logging.

Highly invasive tree species are more dependent on mutualisms

“…For each Pinus species included in the database (Appendix : Table S1) we obtained information on life‐history traits from different sources (Committee‐for‐Compilation‐of‐Chinese‐Tree‐Species‐Manuals , Grotkopp et al , Krugman and Jenkinson , Zhao et al , McGregor et al , Yang et al ). We were interested in the different traits that were found to predict invasiveness (seed mass, juvenile period, and interval between large seed crops) and were therefore used to calculate an invasion index (i.e., the Z score; Rejmánek et al ; see also Rejmánek and Richardson ).…”

The role of demographic compensation in stabilising marginal tree populations in North America

“…Demographic compensation is a function of both among‐population variance of different vital rates as well as the sensitivity of λ to such variance (Villellas et al, 2015). The λ of long‐lived organisms, such as trees, is generally sensitive to survival rate (Schultz et al, 2022; Yang et al, 2018). Natural selection tends to minimise variation in those vital rates to which population growth is most sensitive (Hilde et al, 2020; Pfister, 1998; Zuidema & Franco, 2001).…”