Efeito da diversidade vegetal sobre a comunidade de insetos em um programa de restauração da Caatinga

Abstract

Forest restoration experiments are of great importance for the recovery of degraded areas of Caatinga, providing the development of new restoration technique. A possible approach to evaluate the success of restoration techniques would be to understand the way tree species diversity would affect the colonization of degraded areas by other trophic levels, such as insects. This work aims to analyse how plant diversity in restored plant communities influence insect colonization during the initial stages of restoration. The study was conducted at the National Forest of Açu (RN, Brazil). The experiment was implemented in 2016, for the restoration of a Caatinga area, in which 4,704 seedlings of 16 native tree species were planted. The species were distributed in 155 plots of 8 x 13 m implemented using five levels of plant diversity: 1 species, 2 species, 4 species, 8 species and 16 species, per plot. In the rainy session of 2017, June and July, all plants were surveyed and the insects found were manually collected, stored and identified. To understand the relationship between plant diversity and insect richness and abundance, factorial ANOVAs were performed. A total of 799 insects were collected and 66 OTUs registered. Insect diversity and abundance were significantly higher when plant diversity was higher (8 and 16 species). In addition, the leguminous tree species Mimosa tenuiflora and Piptadenia stipulacea were more attractive to insects than the other plant species studied. We conclude that restoration plots planted with high plant species diversity improved the colonization of new trophic levels. Therefore, planting using high plant diversity might be a promising technique for Caatinga restoration.