Fire rather than nitrogen addition affects understory plant communities in the short term in a coniferous‐broadleaf mixed forest

Abstract

Increasing fire risk and atmospheric nitrogen (N) deposition have the potential to alter plant community structure and composition, with consequent impacts on biodiversity and ecosystem functioning. This study was conducted to examine short‐term responses of understory plant community to burning and N addition in a coniferous‐broadleaved mixed forest of the subtropical‐temperate transition zone in Central China. The experiment used a pair‐nested design, with four treatments (control, burning, N addition, and burning plus N addition) and five replicates. Species richness, cover, and density of woody and herbaceous plants were monitored for 3 years after a low‐severity fire in the spring of 2014. Burning, but not N addition, significantly stimulated the cover (+15.2%, absolute change) and density (+62.8%) of woody species as well as herb richness (+1.2 species/m2, absolute change), cover (+25.5%, absolute change), and density (+602.4%) across the seven sampling dates from June 2014 to October 2016. Light availability, soil temperature, and prefire community composition could be primarily responsible for the understory community recovery after the low‐severity fire. The observations suggest that light availability and soil temperature are more important than nutrients in structuring understory plant community in the mixed forest of the subtropical‐temperate transition zone in Central China. Legacy woody and herb species dominated the understory vegetation over the 3 years after fire, indicating strong resistance and resilience of forest understory plant community and biodiversity to abrupt environmental perturbation.

Assessing the roles of nitrogen, biomass, and niche dimensionality as drivers of species loss in grassland communities

“…The csv files and R file have been deposited in Figshare, https://figshare.com/s/d2933788bc55814b47f3 ( 64 ). Previously published data were used for this work ( 8 , 27 , 34 , 43 , 44 , 53 , 65 …”

Forest Understorey Vegetation: Colonization and the Availability and Heterogeneity of Resources

“…Immediately after fire, adequate growth space and resource availability greatly favor the establishment of vascular plants, which are fast-growing, nutrient-demanding, and shade-intolerant [8]. Moreover, higher soil temperatures are beneficial for breaking seed dormancy and promoting seed germination [36], while enhancing the abundance and diversity of understorey vegetation [37]. The cover and richness of understorey vegetation tend to peak within the first 40 years following fire disturbances in boreal forests [8].…”

Fire as a key driver of Earth's biodiversity

“…The relatively stable post‐Miocene history and establishment of semi‐arid and highly seasonal (Mediterranean‐type) climates in southwestern Africa have also been assumed to be major contributors to diversity (Goldblatt & Manning, ). Although a role for the presence of wildfire as a stimulus for species diversification was proposed long ago (Mutch, ), it has only received attention more recently (He, Lamont & Manning, ; Rundel et al, , ) and has been shown to have a dominant, even pre‐emptive, role compared with other likely environmental constraints (Hu et al, ; Lamont, He & Yan, ). In attempts to understand the distribution and diversity of species, disturbance by fire as a key agent of selection has long been overlooked, and continues to be so (Pausas & Lamont, ; Magadzire et al, ; Pausas & Bond, ).…”

“…In attempts to understand the distribution and diversity of species, disturbance by fire as a key agent of selection has long been overlooked, and continues to be so (Pausas & Lamont, ; Magadzire et al, ; Pausas & Bond, ). However, there is increasing evidence to suggest that prevailing fire regimes make a major contribution to explaining plant diversity at both the community (Burkle, Myers & Belote, ; Hu et al, ) and global (Pausas & Ribeiro, ) scales compared with other possible constraints.…”