Inventory of road arborization on the urban section of BR-153 Gurupi-TO

Abstract

Roadside tree planting involves integrating the road into the landscape. Therefore, the objective of this study was to assess the tree vegetation in the urbanized, duplicated section of BR-153 highway in Gurupi, Tocantins. Permanent plots were systematically established along the central and lateral medians, each measuring 10x10m (100m²) in size, totaling 146 plots in the central median (CM), 54 in the right lateral median (RLM), and 49 in the left lateral median (LLM). Within these plots, all tree individuals with a minimum height of 4.0m from the ground and a diameter at breast height (DBH) ≥ 5cm were sampled.In the inventory, a total of 260 individuals were counted in the central median, distributed across 24 species and 7 families, with a Shannon diversity index (H') of 1.98 and Pielou's evenness index (J') of 0.62. In the right lateral median, 92 individuals were recorded, representing 13 species and 5 families, with (H') of 2.13 and (J') of 0.83. In the left lateral median, 68 individuals were registered, comprising 15 species and 6 families, with (H') of 2.06 and (J') of 0.76, which is consistent with studies conducted in the region. The average height of the vegetation was 6.6m, and the mean diameter along the stretch was 29.99 cm. The species with the highest importance values were Tabebuia roseo alba (Ridl.) Sandwith, Delonix regia (Bojer ex Hook.) Raf., and Syagrus harleyi Glassman. The families with the highest importance values were Bignoniaceae, Anacardiaceae, Fabaceae, and Arecaceae. Of the species found, 57.14% are recommended tree species for highway tree planting. However, it is worth noting that the high number of individuals of the exotic species Delonix regia (flamboyant) may be considered a negative aspect, as it may compromise the diversity of the Brazilian flora by outcompeting native species.