THE MICROCLIMATE OF DIFFERENT LANDSCAPE ARRANGEMENTS IN STREET TREES OF CURITIBA-PR STATE/O MICROCLIMA DE DIFERENTES ARRANJOS PAISAGISTICOS NA ARBORIZACAO DE RUAS DE CURITIBA--PR

Microclimate improvement is frequently stated as one of the benefits generated by urban forestry. However, there are still few studies that quantitatively approach this issue. The goal of this study was to quantify the microclimatic difference between streets with and without trees, for each season and landscaping type. For this, three locations were chosen. Each location showed different species composing landscaping types: Tipuana tipu, Handroanthus chrysotrichus, and Lafoensia pacari with Parapiptadenia rigida. A Kestrel[R] mini station was placed on a street with trees and another one on a street without trees. The daily period for collecting this data was from 9 a.m. to 3 p.m., with monitoring intervals of 1 minute, repeated during the four seasons of the year, beginning in the winter of 2011. The microclimatic variables analyzed were temperature, relative humidity and wind speed. The results indicated that the streets with trees always had lower temperatures and greater relative humidity values than the streets without trees. The greatest temperature difference was observed in the summer (2.5[degrees]C) and the smallest one in the winter (1.2[degrees]C). For relative humidity, the differences were between 6.4% (spring) and 5.6% (winter), and for wind speed the greatest difference was found in the winter (0.17m/s). Landscaping that uses Tipuana tipu on both sides of the street, planted in a way such as to make their canopies entangle and form a tunnel, is the best choice for a more pleasant microclimate in all seasons of the year. Keywords: microclimate; streets with trees; landscaping types. A melhoria microclimatica e frequentemente apontada como um dos beneficios gerados pela arborizacao urbana. No entanto, ainda sao poucos os estudos que abordam quantitativamente essa questao. O objetivo dessa pesquisa foi quantificar a diferenca microclimatica entre ruas arborizadas e sem arborizacao, para cada estacao do ano e arranjo paisagistico. Para isto foram selecionados tres locais, contendo um trecho de rua com e sem arborizacao. Cada local apresentava diferentes especies compondo os arranjos paisagisticos: Tipuana tipu, Handroanthus chrysotrichus e Lafoensia pacari com Parapiptadenia rigida. Para o monitoramento das variaveis meteorologicas, uma miniestacao da marca Kestrel[R] permaneceu na rua arborizada e a outra na rua sem arborizacao. A coleta desses dados foi das 9 as 15 horas, com intervalo de monitoramento de 1 minuto, repetida nas quatro estacoe