Multi-trophic biodiversity increases with increasing structural complexity of forest canopy

Background/Question/Methods

Understanding the effects of forest canopy structural complexity (CSC) on multi-trophic diversity is critical for conserving biodiversity and managing land sustainably. But multi-trophic diversity is often ignored when making decisions about land management due to lack of cost- and time-effective methods to evaluate it. Here we explore a new method based on widely available remote sensing data to quantify CSC and its relationships with multi-trophic biodiversity at continental scale using forested sites of the National Ecological Observatory Network (NEON). We asked (1) does structural complexity of forest canopy affect multi-trophic (primary producers, herbivores (beetles), carnivores (birds)) biodiversity? and (2) do all trophic layers show similar patterns in response to increasing structural complexity? We used plant presence, beetle pitfall trap, and bird count data to calculate species richness and species diversity at each trophic level, and high density LiDAR data for calculating structural complexity metrics of forest canopy at 32 NEON sites.

Results/Conclusions

Our results show that species richness and diversity (Shannon diversity index) at all trophic levels generally increased with increasing structural complexity but relationships differed across different forest types (deciduous, mixed, and evergreen). Our results highlight the importance of maintaining structural complexity in forest canopies for conserving multi-trophic biodiversity.