High tree diversity enhances light interception in tropical forests

We used two forest plantation experiments, the Sardinilla site in Panama (containing monocultures, 2-, 3- and 5-species mixtures in the main plantation, established in 2001, and 6-, 9- and18-species mixtures in the high-diversity plantation, established in 2003), and the Anhembi site in Brazil (established in 2006, containing 20-, 58- and 114-species mixtures), to investigate the effects of forest tree richness on the amount and distribution (horizontal, vertical and temporal) of intercepted ligh (red:far-red ratio - R:FR - for Sardinilla and intercepted photosynthetically active radiation - iPAR - for Anhembi). At the Sardinilla site, light interception was higher in 5-species mixtures than in 2- or 3-species mixtures, and all mixtures presented higher light interception than monocultures. At the Anhembi site, during the dry season, 20-, 58- and 114-species mixtures, respectively, presented increasing light interception. However, during the rainy season, 58- and 114- species mixtures d...