Phenotypical Variability of Functional Groups of Plants in an Urban Rainforest

Abstract

The functional characteristics of plants can be used to understand the changes of vegetation under different environmental pressures, since during the process of succession, the species deal with variations of luminosity, an important resource for the regeneration and growth of plants in humid tropical forests. From the perspective that along the succession there is variation of light availability and that leaf characteristics such as specific leaf area, chlorophyll content and leaf dry matter content are more plastic in groups linked to the rapid acquisition of the resource at the beginning of the succession, it was tested the hypothesis that at the beginning of the succession, where there is greater availability of light, leaf characteristics would be more plastic for the acquisitive group. It was initially found that the geographic distances did not influence the values ​​of the variability indices of the groups, which allows to infer that the distance between the areas does not interfere in the variability of the leaf characteristics. To answer the hypothesis that at the beginning of the succession, in which there is greater light availability, the leaf characteristics would be more plastic for the purchasing group than for the conservative ones, a simple linear regression analysis (ARLS) was performed in the indices of variability for the groups (acquisitive and conservative) and abiotic factor (light) in each area of ​​occurrence. However, the hypothesis that at the beginning of the succession, where there is greater light availability, the characteristics of the leaf would be more plastic for the species was rejected for the species acquisitive, since all indices were reduced for the purchasing group. It is important to take into account that the variation of leaf characteristics as a function of the light availability in an urban tropical fragment is different from what occurs in the classic succession commonly reported, pointing out that possible disturbances caused by the surroundings are the main agents of the functional structure of the community.