Chin J Plan Ecolo ›› 2018, Vol. 42 ›› Issue (6): 653-662.DOI: 10.17521/cjpe.2018.0025

• Research Articles • Previous Articles     Next Articles

Drivers of composition and density pattern of tree seedlings in a secondary mixed conifer and broad-leaved forest, Jiaohe, Jilin, China

MENG Ling-Jun,YAO Jie,QIN Jiang-Huan,FAN Chun-Yu,ZHANG Chun-Yu,ZHAO Xiu-Hai()   

  1. Research Center of Forest Management Engineering of State Forestry and Grassland Administration, Beijing Forestry University, Beijing 100083, China
  • Received:2018-01-16 Revised:2018-06-09 Online:2018-06-20 Published:2018-06-20
  • Contact: Xiu-Hai ZHAO
  • Supported by:
    Supported by the Key Project of National Key Research and Development Plan(2017YFC0504005);the Program of National Natural Science Foundation of China(31670643)

Abstract:

Aims Our aim is to explore the composition and temporal dynamics of tree seedlings and to further understand the impacts and relative importance of biotic neighborhood and habitat heterogeneity on seedling density patterns in a secondary mixed conifer and broad-leaved forest in Jiaohe, Jilin Province, North-eastern China.

Methods We established 209 seedling census stations in the mixed conifer and broad-leaved forest. Based on two seedling censuses conducted in 2016 and 2017, we analyzed species composition and quantitative dynamics of seedlings. Generalized mixed linear models were used to test the relative effects of biotic neighborhood and habitat heterogeneity on seedling density patterns.

Important findings (1) A total of 4 245 seedlings were investigated in all seedling census stations of this plot, belonging to 12 genera, 10 families and 18 species. The number of new-born seedlings varied greatly among species and census years. Fraxinus mandschurica and Tilia amurensis seedlings occurred and died in large numbers. (2) At the community level, the sum of conspecific adult basal area, the soil total phosphorus and available potassium exhibited significant positive effects on seedling density. The habitat suitable for trees was also suitable for seedlings. (3) The factors influencing seedling density of Fraxinus mandschurica were consistent with those of seedling density at the community level. Pinus koraiensis had significant habitat preference, it had higher density in the habitat with lower moisture, soil total phosphorus, available nitrogen, and available phosphorus. Conspecific adult neighbor effects on annual seedling density was more significant than on perennial seedling density. This study suggests that dispersal limitation and habitat filtering together affect seedling density pattern, and the relative importance of biotic neighbors and habitat heterogeneity varies among seedling species and age classes.

Key words: secondary mixed conifer and broad-leaved forest, generalized linear mixed-effect model, tree seedling density, biotic neighbor, habitat heterogeneity