Diversity of macromycetes determined by tree species, vegetation structure, and microenvironment in tropical cloud forests in Veracruz, Mexico

Abstract

Tropical montane cloud forests (TMCFs) have high levels of plant and fungal diversity. We examined whether macromycete alpha and beta diversity were associated with woody plant diversity, forest structure, or microclimate, in four TMCFs at lower (1240–1440 m) and upper altitudes (1790–1900 m) in Veracruz, Mexico. Every 2 weeks during the growing season, macromycetes were collected from ten 10 m × 10 m permanent plots per site, and air and soil temperature and humidity were measured. In total, 2059 macromycetes (509 species) and 678 woody plants (63 species) were recorded. Macromycete diversity (Shannon Index) values of the two sites located in lower forests were higher than in upper sites. Beta diversity (Jaccard index) indicated high turnover among sites and sampling times. Macromycete richness was negatively correlated with overstorey tree richness, understorey vegetation structure, and air temperature, but was positively correlated with air humidity and soil water content and altitude. Ordinations separated lower from upper altitude forest sites. Changes in composition and abundance of macromycete species with altitude were explained by precipitation, temperature, and understorey vegetation structure, while soil water content effect changes within a growing season. Results imply that understorey vegetation structure is a more important aspect for macrofungal diversity management than for woody plant diversity.