HEALTHY OR HAZARDOUS? THE HIDDEN SIDE OF PUBLIC PARK RECREATION REVEALED BY ITS METABARCODING OF URBAN PARK SOILS

Abstract

Public parks have been increasingly used for outdoor recreation and leisure activities such as running, aerobic dancing, bird feeding and picnicking. Frequent human interaction with urban birds, particularly pigeons, may increase exposure to potentially pathogenic microorganisms. This study investigated potential health risks associated with environments heavily populated by birds in urban parks. Soil samples in areas of high bird-human interactions were collected from two public parks in Bangkok, Thailand. Fungal communities in the soil samples were analysed using internal transcribed spacer (ITS) metabarcoding combined with bioinformatics approaches to assess microbial diversity and identify potentially pathogenic taxa. Results revealed that Ascomycota was the dominant fungal phylum across all samples, accounting for 89.9% of fungal reads. Beta diversity analysis demonstrated compositional differences in fungal communities between the two parks, although neither beta nor alpha diversity differences were statistically significant, likely due to limited statistical power with three samples per site. Functional guild analysis showed that Pathotroph-Saprotroph-Symbiotroph, Saprotroph, and Pathotroph-Saprotroph were the dominant trophic modes. Several fungal genera with known opportunistic pathogenic potential, including Aspergillus, Fusarium, Curvularia, and Chaetomium, were also detected. Environmental observations further indicated that areas with higher bird abundance and more frequent human-bird interactions were associated with site-specific fungal community compositions. As ITS metabarcoding detects DNA rather than viable organisms, these findings indicate potential environmental reservoirs rather than a demonstrated health hazard, highlighting the need for microbial ecological considerations in urban park management.

Keywords: Public Parks, Fungal Pathogens, ITS Metabarcoding, Bird-Associated Pathogens, Public Health Risk