AUTHOR=Gong Chao , Zeng Xiaoxia , Zhu Xianglong , Huang Wenhui , Compson Zacchaeus G. , Ren Zewen , Ran Huan , Song Qingni , Yang Qingpei , Huang Dongmei , Liu Jun 

TITLE=Bamboo expansion promotes radial growth of surviving trees in a broadleaf forest

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1242364

DOI=10.3389/fpls.2023.1242364

ISSN=1664-462X

ABSTRACT=<sec><title>Introduction</title><p>Considerable evidence indicates that some trees are more vulnerable than others during bamboo (<italic>Phyllostachys edulis</italic>) expansion, which can affect plant community structure and alter the environment, but there has been insufficient research on the growth status of surviving individuals in colonized forests.</p></sec><sec><title>Methods</title><p>In this study, we compared the annual growth increment, growth rate, and onset, cessation, and duration of radial growth of <italic>Alniphyllum fortunei</italic>, <italic>Machilus pauhoi</italic>, and <italic>Castanopsis eyrei</italic> in a bamboo-expended broadleaf forest (BEBF) and a bamboo-absent broadleaf forest (BABF) using high-resolution point dendrometers.</p></sec><sec><title>Results</title><p>We found that the annual radial growth of <italic>A. fortunei</italic>, <italic>M. pauhoi</italic>, and <italic>C. eyrei</italic> was 22.5%, 172.2%, and 59.3% greater in BEBF than in BABF, respectively. The growth rates of <italic>M. pauhoi</italic> and <italic>C. eyrei</italic> in BEBF were significantly higher than in BABF by13.9 μm/d and 19.6 μm/d, whereas <italic>A. fortunei</italic> decreased significantly by 7.9 μm/d from BABF to BEBF. The onset and cessation of broad-leaf tree growth was later, and the growth duration was longer in BEBF compared to BABF. For example, <italic>A. fortunei</italic> and <italic>M. pauhoi</italic> in BEBF had more than one month longer growth duration than in BABF. Additionally, the nighttime growth rates of some surviving broad-leaf trees in BEBF was significantly higher than that in BABF.</p></sec><sec><title>Discussion</title><p>These results suggest that the surviving trees have plasticity and can adapt to atmospheric changes and competitive relationships after expansion of bamboo in one of two ways: by increasing their growth rates or by modifying onset and cessation of growth to extend the growth duration of trees or avoid the period of intense competition with bamboo, thereby growing better. Our research reveals for the first time how the growth of surviving broad-leaf trees adjusts to bamboo expansion. These results provide insights into how biological expansions impact primary production and have implications for forest management in the Anthropocene.</p></sec>