학술논문

Canopy and understorey tree guilds respond differently to the environment in an Indian rain forest.
Document Type
Article
Source
Journal of Vegetation Science. Sep2021, Vol. 32 Issue 5, p1-9. 9p.
Subject
*RAIN forests
*OPTICAL radar
*LIDAR
*GUILDS
*COMMUNITY forests
Language
ISSN
1100-9233
Abstract
Questions: Changes in the functional composition of tree communities along resource availability gradients have received attention, but it is unclear whether understorey and canopy guilds respond similarly to different light, biomechanical, and hydraulic constraints. Location: An anthropically undisturbed, old‐growth wet evergreen dipterocarp forest plot located in Karnataka State, India. Methods: We measured leaf and wood traits of 89 tree species representing 99% of all individuals in a 10‐ha permanent plot with varying topographic and canopy conditions inferred from Light Detection And Ranging (LiDAR) data. We assigned tree species to guilds of canopy and understorey species and assessed the variation of the guild‐weighted means of functional‐trait values with canopy height and topography. Results: The functional‐trait space did not differ between canopy and understorey tree species. However, environmental filtering led to significantly different functional composition of canopy and understorey guild assemblages. Furthermore, they responded differently along environmental gradients related to water, nutrients, light, and wind exposure. For example, the canopy guild responded to wind exposure while the understorey guild did not. Conclusions: The pools of understorey and canopy species are functionally similar. However, fine‐scale environmental heterogeneity impacts differently on these two guilds, generating striking differences in functional composition between understorey and canopy guild assemblages. Accounting for vertical guilds improves our understanding of forest communities' assembly processes. [ABSTRACT FROM AUTHOR]