广西三种阔叶树人工纯林及其与马尾松混交模式的生长评价

Growth evaluation of three types of pure broad-leaved forests and their mixed stands with Pinus massoniana in Guangxi

关键词:  黑格，枫香树，荷木，马尾松，混交模式，生长差异及评价

Key words:  Albizia odoratissima, Liquidambar formosana, Schima superba, Pinus massoniana, mixed planting pattern growth differences and evaluation

摘要:

黑格、枫香树和荷木是广西重要的乡土阔叶造林树种，为研究其纯林及其在马尾松林下混交的造林效果，该研究用这3种阔叶树的1年生容器苗进行纯林和马尾松林下混交造林，3年后调查分析其树干、树冠生长和树干干形的差异，并采用层次分析法对其生长情况进行综合评价。结果表明：（1）纯林模式下黑格、枫香树的树高、胸径较大，且多干率较低，树干生长较好，而林下混交模式下荷木的树高、胸径较大，树干生长较好。（2）纯林和马尾松林下混交模式下黑格的冠幅、枝下高和自然整枝能力均较大，且冠径比相对较小，其树冠生长较好。纯林模式下枫香树的分杈率、高径比较小，其树干干形较好，马尾松林下混交模式下荷木的高径比、倒伏率较小，其树干干形较好。（3）生长情况综合评价结果为：黑格纯林>枫香树纯林>林下荷木>林下黑格>荷木纯林>林下枫香树。因此，纯林模式下生长情况最好的为黑格，马尾松林下混交模式下生长情况最好的为荷木。该研究结果为黑格、枫香树和荷木在广西区域内栽培技术研究提供科学依据和理论参考。

Abstract:

Albizia odoratissima, Liquidambar formosana, and Schima superba are key native broad-leaved tree species for afforestation in Guangxi, China. To assess the afforestation performance of these species in both pure stands and understory mixed stands with Pinus massoniana, a field experiment was conducted using one-year-old container-grown seedlings of the three broad-leaved species. Two planting configurations were established: pure stands of each species, and mixed stands where each species was interplanted under Pinus massoniana canopies. After three years of growth, differences in trunk growth, crown development, and stem form among the treatments were investigated and analyzed. Additionally, the Analytic Hierarchy Process (AHP) was employed to conduct a comprehensive evaluation of the overall growth performance of each species under different configurations.The results were as follows: (1) In pure stands, Albizia odoratissima and Liquidambar formosana exhibited superior trunk growth, characterized by greater tree height, larger diameter at breast height (DBH), and a lower ratio of multiple tree trunks. In contrast, Schima superba achieved better trunk growth (i.e., greater height and DBH) in the understory mixed stand configuration. (2) Regardless of the planting configuration (pure stand or understory mixed stand with Pinus massoniana), Albizia odoratissima showed excellent crown development. This was reflected in its larger crown diameter, greater Under-branch?height, stronger natural pruning ability, and a relatively smaller Crown-diameter ration. (3) For stem form, Liquidambar formosana performed optimally in pure stands, with a lower probability of bifurcation and a smaller height-diameter ratio. Meanwhile, Schima superba displayed better stem form in the understory mixed stands, as evidenced by a smaller Height-diameter ratio and a lower lodging rate. (4) The comprehensive AHP evaluation of growth performance ranked the treatments in the following order: Albizia odoratissima (pure forests) > Liquidambar formosana (pure forests) > Schima superba (understory) > Albizia odoratissima (understory) > Schima superba (pure forests) > Liquidambar formosana (understory). Consequently, Albizia odoratissima is identified as the top-performing species in pure stands, while Schima superba is the most suitable for understory mixed planting with Pinus massoniana.This study provides a scientific basis and theoretical reference for optimizing the cultivation techniques of Albizia odoratissima, Liquidambar formosana, and Schima superba in the Guangxi region.