Functional variability of macrofungal populations in four different forest types of Costa Rica

Abstract

A series of functional variables, including biomass and hymenial area, were obtained for more than 4800 individual macrofungal sporocarps and correlated with a set of ecological parameters characterizing soil, climate and forest structure in four different forest types of Costa Rica. The idea behind this project was to document macrofungi over a three-year period with the objective of generating a dataset intended to document sporocarp variability and association with forest characteristics. In the context of climate change, habitat degradation and tropical forest fragmentation, studying fungi from an ecological perspective can provide crucial elements of analysis to weigh their relevance in tropical systems and to understand the potential threats to fungal populations. Our results showed high variability in the functional variables over the period of study, but suggest that such variability is partially induced by macroclimatic events in which forests with a higher percentage of mycorrhizal fungi seemed to be more sensitive. Overall, the ratio of hymenial area/biomass and pileus diameter were found to be significantly correlated with several ecological parameters in the studied forest types. However, the association of the former with ecological reproductive strategies makes such variable a good parameter to use for the monitoring of fungal dynamics in the studied tropical forests. The potential application of the latter in the framework of climate change and forest degradation studies is relevant since fungi are essential organisms in tropical ecosystems.