Chin J Plant Ecol ›› 2022, Vol. 46 ›› Issue (9): 1005-1017.DOI: 10.17521/cjpe.2022.0094

Special Issue: 青藏高原植物生态学:植被生态学 青藏高原植物生态学:数据论文 植被生态学

• Research Articles • Previous Articles     Next Articles

Community composition and structure in a 25.2 hm2 subalpine dark coniferous forest dynamics plot in Wanglang, Sichuan, China

FAN Fan1,2, ZHAO Lian-Jun3, MA Tian-Yi1, XIONG Xin-Yu2,4, ZHANG Yuan-Bin5, SHEN Xiao-Li6,*(), LI Sheng1,2,*()   

  1. 1School of Life Sciences, Peking University, Beijing 100871, China
    2Institute of Ecology, Peking University, Beijing 100871, China
    3Wanglang National Nature Reserve, Pingwu, Sichuan 622550, China
    4College of Urban and Environmental Sciences, Peking University, Beijing 100871, China
    5Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, China
    6State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China
  • Received:2022-03-15 Accepted:2022-05-31 Online:2022-09-20 Published:2022-10-19
  • Contact: SHEN Xiao-Li,LI Sheng

Abstract:

Aims Subalpine dark coniferous forests are an important representative of the cold-temperate coniferous forests in China. Dark coniferous forests dominated by spruce (Piceaspp.) and fir (Abies spp.) are the main body of subalpine forests on the eastern edge of the Qingzang Plateau and an important ecological defense in the upper reaches of the Yangtze River in China. In this study, we examined the community composition and structure of such a dark coniferous forest based on the first census data of the 25.2 hm2 Wanglang forest dynamics plot in western Sichuan.

Methods The plot was established following the standard protocol of Forest Global Earth Observation Network (ForestGEO) and all free-standing stems with diameter at breast height (DBH) ≥ 1 cm were tagged, mapped, measured and identified to species.

Important findings A total of 56 574 individuals belonging to 46 species, 27 genera and 15 families are tagged, including 4 coniferous species, 6 evergreen broad-leaved species and 36 deciduous broad-leaved species. There are 13 rare species (≤1 individuals per hm2), accounting for 28.26% of the total number of species and 0.16% of the total number of individuals in the plot. Abies fargesiivar. faxoniana(9 440 individuals) and P. purpurea (1 645 individuals) are the dominant and constructive species in canopy, accounting for 26.03% and 10.69% of the total importance value, and 55.22% and 24.84% of the total basal area (37.87 m2·hm-2), respectively. The number of individuals of deciduous broad-leaved species accounted for 78.48% of the total individuals. Among them, Philadelphus purpurascens, Lonicera nervosaand Euonymus frigidusare the dominant species in shrub layer. The number of individuals of evergreen broad-leaved species is 268, and all these species belong to genus Rhododendron. The composition of the size distribution shows typical characteristics of old-growth forests. Picea purpurea is the largest tree species (max DBH = 127.07 cm) and the mean basal area (0.14 ± 0.18) m2 is much higher than that of A. fargesiivar. faxoniana(0.056 ± 0.11) m2. The size class distribution of all woody species shows an inverse J-shaped distribution, indicating that the community is in a stable and healthy recruitment state. Results of the point pattern analysis reveal that the five dominant tree species (important values ≥5) all show aggregated distribution patterns. However, as the spatial scale increases, all five species tend to be randomly distributed. The results of this study provide basic information for future studies on the diversity maintenance and regeneration mechanisms of subalpine dark coniferous forests in western Sichuan, and the conservation and management of this unique forest ecosystem.

Key words: CForBio network, subalpine dark coniferous forest, Minshan Mountains, species composition, community structure, point pattern analysis