The influences of ground surface substrates on ant community in urban landscape

Abstract

Urbanization is common all over the world and create areas hotter than the surrounding rural areas (i.e., urban heat islands). Climate change is predicted to further push temperatures in urban environments to a new high and thus affect animal communities. As an ecological indicator, the responses of ants to common urban ground surface substrates were investigated. This study aims to examine whether there was variation in ground temperatures of different substrates and how this affects ant community. Baiting experiments on lawn and three different pavement substrates (bricks, concrete and tiles) were conducted at the same time and there were two treatments on each substrate – under sun or shade. The ground surface temperature (GT) of substrates was measured and the critical thermal maximum (CTmax) of the ants foraging in these habitats were also tested. The GT was found to be significantly different on different substrates (from the highest to the lowest: bricks, concrete, tiles and lawn). Nineteen ant species were found, with foraging preferences on lawn and bricks, but less on tiles and not on concrete. The CTmax of ants appear to have a positive relationship with GT. The GT is perceived as one of the major drivers for ant activities. Moreover, the importance of shade in creating refuges for ants was observed. Some recommendations have been provided for urban planning and management according to the study results. More work on urban landscape ecology of ants are encouraged.