Data on fungal community composition and dead wood diversity and volume in 24 forests in South-Eastern Norway.

This study evaluates how different facets of functional diversity of dead wood (richness, evenness, divergence, and dispersion) combined with volume affect communities of fruiting polyporoid and corticioid fungi in Agaricomycetes. Using an existing study system, where dead wood has been surveyed in paired clear-cut and near-natural forests, we test the impact of functional diversity on fungal communities. Our findings reveal that near-natural forests exhibit higher fungal species richness due to greater volume and diversity of dead wood. We demonstrate that a unified measure of dead wood volume and functional diversity better predicts fungal species richness and community composition than either factor alone. Functional divergence and evenness of dead wood are key predictors, with high functional divergence indicating a variety of niches and high functional evenness suggesting well-distributed niche availability. These results highlight the importance of both the quantity and structural heterogeneity of dead wood in maintaining fungal diversity. Conservation efforts and forest management should focus on enhancing both the volume and structural diversity of dead wood to support diverse fungal communities. This study provides valuable insights into species assembly processes and underscores the need for integrated measures of dead wood characteristics in ecological studies.