Recovery of understory vegetation biomass and biodiversity in burned larch boreal forests in Northeastern China

ABSTRACT

Recovery of biomass and biodiversity of forest understory vegetation after fire disturbance has been widely studied; however, how this relationship changes and what are the determinants at different post-fire stages in larch boreal forests are still unclear. We investigated a chronosequence of 81 understory plots in larch boreal forests that were disturbed by fires in 1987 (S5), 1992 (S4), 1996 (S3), 2002 (S2), or 2007 (S1). Analysis of variance was conducted to test the differences of biodiversity and biomass among various post-fire stages. Different regression models were used to fit the relationship between biomass and biodiversity, while factors influencing this relationship were identified by boosted regression tree analysis. Results showed that total understory biomass increased from 2.51 t ha⁻¹ in S1 to 8.47 t ha⁻¹ in S3 and declined to 5 t ha⁻¹ in S5. Similar dynamics were also found between species richness and species diversity. Positive linear correlations linked biomass and biodiversity throughout most of the post-fire periods. Slope and stand density were the two most important factors influencing the secondary succession of understory vegetation after fire. Geographical factors and overstory competition determine the orientation of vegetation recovery, and the impacts of climate on vegetation are muted after fire disturbances.

Keywords:

• Secondary succession
• understory vegetation
• post-fire stages
• biomass and diversity
• larch boreal forests
• great Xing'an Mountains

Acknowledgements

We thank Hongwei Chen, Wei He, Haifeng Wu, Xiaoli Wang, Chunlin Li, Linlin Jiao, Fengyun Sun, Wen Wu, Tan Chen, Dan Shen, and Hao Wang for their help in data collection. We also thank “Edanz”, a Professional Scientific Editing Services company, for the help of language revision.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was funded by the “Strategic Priority Research Program – Climate Change: Carbon Budget and Related Issues” of the Chinese Academy of Sciences (XDA05050201).