2023

Norros, Veera; Halme, Panu; Norberg, Anna; Ovaskainen, Otso

Traits related to reproduction and dispersal drive the assembly and dynamics of species communities and can explain and predict how species respond to habitat loss and fragmentation and to the changing climate. For fungi, such links remain poorly known. We examine how spore production rate, a key demographic trait, is influenced by the interaction between environmental conditions and species traits. We monitored the spore production of 97 wood-inhabiting fungal species on 107 decaying logs for 2 years and analysed the data with a hierarchical community model. Our analysis demonstrates clear species differences in seasonal patterns, with spring and summer release dominating in perennial species, contrary to the commonly held view of autumn as the primary “mushroom season”. Many species follow a diurnal pattern with a higher spore release rate during the night. Such patterns in release timing have important implications for dispersal, as shown by recent model simulations. The overall level of spore release was negatively correlated with spore size, providing new evidence that fungi face the classic trade-off of investing either in the number or size of offspring. We found that different species within the functional group of wood-inhabiting fungi display alternative strategies in spore release timing and along the trade-off between offspring size and number. Linking our findings to previously reported correlations between spore size and other traits, we propose a new conceptualization of life history strategies in wood-inhabiting fungi, with implications for species' ability to survive the ongoing biodiversity crisis.