Effect of chemical and mechanical management of bamboo on seed rain in riparian areas

Abstract

Bamboo species are cultivated for different purposes around the world, mainly because they adapt easily to environmental changes. However, their aggressive growth strategies and competitive superiority make bamboos opportunistic, allowing for rapid colonization. The aim of this study was to evaluate the effect of bamboo management methods on the structure and composition of seed rain. We evaluated seed rain in riparian areas with and without bamboo dominance. In the area dominated by bamboo we evaluated: control (no interventions), chemical management, and mechanical management treatments. The area without bamboo dominance is a seasonal semi-deciduous forest remnant, considered a reference ecosystem. The control treatment showed a lower abundance of seed rain than the other treatments. The chemical treatment presented greater total abundance due to the overabundance of the morphospecies Mikania sp.; however, the species richness did not differ from the control treatment. Moreover, the chemical treatment showed low seed input with biotic dispersal, differing from the mechanical and reference treatments. Seed abundance for both dispersal mechanisms (biotic and abiotic) was similar between the mechanical and reference treatments. We concluded that the bamboo management methods favored the increase in seed rain. The bamboo mechanical management treatment facilitated seed dispersal and provided a significant increase in terms of richness and abundance in relation to the control treatment. Despite not showing a significant increase in richness, the chemical management treatment promoted a significant increase in seed abundance in relation to the control treatment.