The environmental gradient influences the concentrations of carbon compounds in the biomass of Protium icicariba (DC.) Marchand in restinga area

The objective of this study was to analyze the concentrations of non-structural carbohydrates and cell wall polymers in Protium icicariba individuals along an environmental gradient of a Coastal Brazilian Atlantic Forest (restinga). The concentrations of non-structural carbohydrates (glucose, fructose, sucrose and starch) and cell wall polymers (cellulose, hemicellulose and lignin) were quantified in samples of stems, branches and leaves of individuals distributed in contrasting zones regarding the occurrence of floods [periodically floodable (PI), transitional (IT) and non-floodable (NI)]. Individuals from the non-flooded zone had higher concentrations of starch and hemicelluloses in the branches and leaves. On the other hand, cellulose and lignin concentrations were higher in the leaves of individuals from the periodically flooded and transitional zones. The variations in the concentrations of non-structural carbohydrates and cell wall polymers were mainly associated with water availability and plasticity of the species, in addition to possible influences of soil nutrient supply and the occurrence of herbivory. The sensitivity in the dynamics of the carbon molecules of P. icicariba in a diverse and spatially short environmental gradient, requires considerable plasticity of the species that, in the imminence of climatic changes, must favor its survival in the face of the imposition of new environmental filters.