Risco potencial de queda de árvores em dois parques urbanos em Belém, estado do Pará

Abstract

The urban forests are ecosystems formed by the interaction between natural and anthropogenic systems, inserting this context streets, avenues, parks, squares, public and private areas and conservation areas. Trees in urban areas are very important to people's quality of life, as they offer numerous benefits to people. However, trees in urban areas could cause accidents by his fall, especially in adverse weather conditions, may cause damage to assets and to people's health. Cities around the world face problems related to the risk of accident tree fall which is enhanced according to what will be achieved. This study aimed to evaluate qualitative and quantitatively the trees of the Zoo-Botanical Park of Museum Paraense Emílio Goeldi (PZB/MPEG) and in the Park Rodrigues Alves Botanical Garden of Amazônia (BRA/JBA), through the evaluation system of the potential risk of falling trees (SARPQA) proposed in this study. It was analyzed the aspects to the diameter (DAP), total height, surface biomass, apparent plant health, trunk inclination, cup balance and vines’s incidence. The data was collected in the months May and July of the 2014 trough inventories. It was evaluated 678 individuals in PZB/MPEG distributed in 157 species and 31 families. The Arecaceae was the most abundant presenting 155 individuals. The specie most abundant was Guarea trichilioides with 47 individuals. In BRA/JBA, were registered 396 individuals, totaling 93 species and 30 families. Fabaceae was the family that showed greater abundance with 70 individuals, Simarouba amara is the most abundant specie with 62 individual. . The SARPQA showed that on PZB/MPEG 20 trees had very high risk falling, 122 showed high risk, 453 individuals showed RQ between 1 and 4 getting in the middle and low risk classes and 88 showed very low risk. For the BRA/JBA the system showed that 3 individuals had very high risk of falling, 20 were in the high risk class, 297 were in the middle and low risk classes and 76 trees showed very low risk class. Studies in parks and plazas aim to solve potential problems related to vegetation, and suggest improvements to preserve the quantity and quality of existing plants, and thus ensure the safety of people who visit these places.