Variação interespecífica em comunidades arbóreas de restinga com base em atributos anatômicos e teores de pigmentos cloroplastídicos

Abstract

Due to the biological relevance of coastal environments, such as restingas, represented by high richness indexes, species diversity and heterogeneity of plant formations, studies are needed to evaluate how global changes can influence the composition of plant communities. In this sense, information about the functional diversity and the characteristics of the species that vary in contrasting environments, such as environmental gradients, represent means to verify the influence of climate changes on plant formations. In this scenario, water availability represents a prominent factor, represented by the projection of irregular rainfall regimes. In order to do so, we measured indexes of functional diversity, such as richness, uniformity, dispersion and functional divergence, besides evaluating the interspecific variation of the species used based on foliar anatomical characteristics and chloroplastidic pigment contents. In addition, we perform a redundancy analysis, in order to verify which is the most significant environmental variable for the attributes used. The water table was the most significant environmental variable in the present study. Among the functional diversity indexes, only richness and functional dispersion were responsive to the anatomical attributes, evidencing that the niches increase as they distance themselves from the water table and provide environments vulnerable to invasion by opportunistic species. The functional diversity indexes for the pigment contents were not responsive to the variation of the water table. Regarding the anatomical characteristics analyzed, the epidermis of the adaxial face was responsive to the variation in the water availability of the water table. However, it is suggested the investigation of other structural characteristics, such as density of garments and intercellular spaces. The levels of chloroplastidic pigments were responsive to the variation of the water table, corroborating with the foliar economic spectrum, where species with aquarium strategies are found at one extreme while species with conservative strategies.