Characterization of Sidewalk Trees and Their Mitigation Effect on Extreme Warm Temperatures in a Tropical City of Mexico

In Mexico, an emerging tropical nation, where cities have insufficient vegetation cover and there is little information about their provision of ecosystem services; the study of urban vegetation, as a mitigation strategy, is required. The sidewalk trees in the city of Arriaga (CAR), considered one of the warmest cities in the Mexican southeast, were counted, measured, and assessed for their effect on surface and air temperatures. There are 6239 sidewalk trees, distributed in 11 families and 13 species; 136 trees were sampled concentrating 77% in three species: Neem, Country almond and Benjamina fig. Therefore, a low H’ (1.73 nats) was obtained. The mitigating effect of tree shade on surface temperature went from 7 °C to 23 °C, depending on the day and hour, while there was not a significant refreshing effect of air temperature because the height of sidewalk trees is controlled with severe pruning to prevent damage to public wiring, causing a similar-sized stratum that traps air under the tree canopy. Consequently, an integral solution that includes, but is not limited to, urban trees is required without leaving aside increasing tree diversity, health, and equitable distribution of trees at CAR.