Species-specific performance and trade-off between growth and survival in the early-successional light-demanding group

Abstract

We investigated if high irradiance imposes stress conditions and differently affects the performance of species from the early-successional light-demanding group and if the costs associated with plasticity underlie the trade-off between growth and survival. Survival, growth, chlorophyll a fluorescence, and carbon stable isotopic ratio (δ13C) were measured in seedlings of four tree species in a restoration area in the Atlantic Forest under full-sun exposure and partial shading treatments. The maximal quantum yield of PSII indicated stress conditions mainly in the full-sun exposure treatment (values from 0.72 to 0.81). The δ13C ranged from -31.9 to -30.4‰, but did not differ between treatments for three species, suggesting that C assimilation in initial restoration conditions is stressful even in shade. The survival scaled negatively with growth and plasticity adjustments. We conclude that early-successional species do not form a homogenous species group because they differ in functional responses to stress, and phenotypic plasticity, with these variations showing a strong link with the trade-off between growth and survival. This information should be taken into account for species selection in restoration programs.