Recruitment niches of Enterolobium contortisiliquum (Vell.) Morong: functional acclimations to light

Abstract

Adjustments that a tree species displays in acclimating to light conditions may explain its fate in different forest successional stages. Enterolobium contortisiliquum (Vell.) Morong is a tree found in contrasting light environments and used in reforestation programs because of its rapid growth. This study analyzed the performance of tamboril seedlings grown in three light environments: FS—full sun (100% of photosynthetically active radiation (PAR) and a red/far-red ratio (R/FR) of 1.66), S—shade net (38% of PAR and a R/FR of 1.54) and I—Insulfilm® (Insulfilm, São Paulo, Brazil) shade cloth (24% of PAR and a R/FR of 0.69). Greater net assimilation, higher root/shoot ratio, higher stomatal density, and reduced leaf area are some of the functional traits developed by tamboril to acclimate to full sun. On the other hand, a larger leaf area associated with a greater specific leaf area, higher leaf area ratio, higher leaf number and leafing intensity, as well as higher chlorophyll and carotenoid contents are among the most important traits for tamboril to acclimate to shade. The seedlings growing in FS displayed the best quality index. However, the traits developed in the nursery under each light condition could promote the successful installation and survival of tamboril seedlings under similar conditions in the field.