Diagnóstico da arborização urbana de três setores do município de Londrina, PR

Abstract

Urban trees, defined as the trees that are part of the landscape on streets and avenues, provide ecological, social and economic benefits to the city and its population. However, for a town to enjoy the benefits of urban trees, it is necessary to make the structure of the physical environment compatible with the presence of trees, in order to reduce the possible conflicts. The aim of the present work is to make a diagnosis of urban trees in three sectors of Londrina, PR, called Aeroporto, Centro Cívico and Gleba Palhano. The main data collected were common name of the plant, height, CAP, relationship between the canopy and the wiring, phytosanitary and maintenance aspects, spaces available for new plantings and distances for establishing coordinates. The situation found was compared to some topics in the Londrina Urban Trees Master Plan, seeking to identify management actions to reach the guidelines of the Law. The urban trees assessment was conducted during 2018 and data of urban infrastructure were also recorded. A group of Environmental Engineering students collected field data. A total of 8,136 points were georeferenced, of which 68.60% were trees, 26.59% were spaces available for planting new trees, 3.84% pits and stumps and 0.97% were dead trees. In total, 142 species were identified, being 55 native, 87 exotics, and 10 are prohibited from planting by Law. The 10 most common species, in each sector, account for more than half of all trees. Oiti (Licania tomentosa) was the most common species in the three sectors, and its frequency is above the recommended by the legislation, both at the Airport and in the Gleba Palhano. In the three sectors, most trees had a height of less than 6.0 meters and the practice of topiary in Oiti contributes to this situation, since trees whose species are large predominate in the community (about 45% in each sector). It was found that 25.87% of the trees broke the sidewalks around them, that 12.09% were surrounded by short walls and that 5.35% did not have enough free area around them. Problems such as termites, borers and/or damage were detected in 8.32% of the plants, 3.40% suffer from drastic or topiary pruning and 1.24% have a fence damaging the individuals. Thereby it was possible to list improvement actions, in view of the irregularities, such as the existence of species prohibited by law, the percentage of exotic species compared to native species and the occurrence of practices such as topiary and drastic pruning. It was also proposed the implementation of programs to raise community awareness, since the diagnosis revealed that irregular practices are a symptom that the population is distant from the legislation.