Dynamics between natural species and Ligustrum lucidum W.T. Aiton in an alluvial Atlantic Forest fragment

Abstract

The introduction of invasive exotic tree species is a threat to natural ecosystems. This study aimed to evaluate the dynamics and growth of tree native species due to coexistence with L. lucidum, in an urban fragment of Alluvial Araucaria Mixed Forest (AAMF), in the municipality of Guarapuava, Paraná, Brazil. Were evaluated the dynamics of trees between the years 2013 and 2018 was evaluated. Regarding floristics, in the two evaluations were founded 14 families, 15 genera and 15 species, from 727 tree individuals in 2013 and 634 tree individuals in 2018. Ingrowth and mortality rates were 6.74% and 19.53%. The Periodic Increment (PI) was 8.90 cm, with the species with the greatest increments being: Gymnanthes klotzschiana (4.13 cm) and L. lucidum (3.93 cm), while Annual Periodic Increment (API) was 1.75 cm. Evaluating a diametric transition opportunity, considering all of our species evaluated, a probability rate of permanence of those belonging to the class with the shortest DBH (5 cm) was 60%, with a probability of migrating to the next class of 20%. With regard to individuals of L. lucidum, it was verified that the transition of individuals does not occur in classes above 35 cm, where the mortality rate is null. Ligustrum lucidum has a higher occurrence in the environment, showing the adaptability of this exotic invasive species in this AAMF fragment.