State of the art and future directions for mycological research in old-growth forests

Diversity and Distribution of Macrofungi in Protected Mountain Forest Habitats in Serbia and Its Relation to Abiotic Factors

Fungal diversity is one of the most important indicators of overall forest biodiversity and its health. However, scarce information exists on the state of macrofungal communities of mountain forests in Serbia, making it one of the countries with the least-published mycological data in the Mediterranean and Balkan region of Europe. This paper presents the results of the first comprehensive, long-term study of macrofungal communities in some of the most important mountain forest ecosystems in Serbia (Tara, Kopaonik and Vidlič). In the course of three consecutive years, the sampling of five permanent experimental plots resulted in 245 species of macrofungi, classified into three functional groups (terricolous saprothrophs, lignicolous, and mycorrhizal fungi). Special attention was given to protected and indicator species, which point out the great value of studied forest habitats and the importance of their conservation. It was found that precipitation, habitat humidity, and temperature significantly influence the occurrence and distribution, primarily of mycorrhizal and lignicolous group of fungi. Thus, the continuation of long-term monitoring is crucial in order to more precisely determine which groups/species of macrofungi would, and to what extent they would, adapt to a rapidly changing climate.

Similarities and Differences among Soil Fungal Assemblages in Managed Forests and Formerly Managed Forest Reserves

Unlike the numerous works concerning the effect of management on the forest mycobiome, only a few studies have addressed how fungi from different trophic groups recover from natural and anthropogenic disturbances and develop structural features typical of unmanaged old-growth forests. Our objective is to compare the soil fungal assemblages represented by different functional/trophic groups in protected and managed stands located in European mixed forests dominated by Scots pine. Fungal communities were analyzed using high-throughput Illumina MiSeq sequencing of fungal internal transcribed spacer 1 (ITS1) amplicons. Formerly managed forest reserves (established around 50 years ago) and forests under standard forest management appeared to be similar in terms of total and mean species richness of all fungal operational taxonomic units (OTUs), as well as OTUs assigned to different functional trophic groups. Among the 599 recorded OTUs, 497 (83%) were shared between both management types, whereas 9.5% of taxa were unique to forest reserves and 7.5% were unique to managed stands. Ascomycota and Basidiomycota were the predominant phyla, comprising 88% of all identified fungi. The main functional components of soil fungal assemblages consisted of saprotrophic (42% fungal OTUs; 27% reads) and ectomycorrhizal fungi (16%; 47%). Two-way analysis of similarities (ANOSIM) revealed that both site and management strategy influenced the species composition of soil fungal communities, with site being a primary effect for saprotrophic and ectomycorrhizal fungi. Volume of coarse and very fine woody debris and soil pH significantly influenced the ectomycorrhizal fungal community, whereas saprotrophic fungi were influenced primarily by volume of coarse woody debris and soil nitrate concentration. Among the identified fungal OTUs, 18 red-listed fungal species were identified from both forest reserves and managed forests, comprising two ECM fungi and four saprotrophs from the category of endangered species. Our results suggest that the transformation of fungal diversity after cessation of forest management is rather slow, and that both forest reserves and managed forests help uphold fungal diversity.

Dead wood fungi in North America: an insight into research and conservation potential

Saproxylic fungi act as keystone species in forest ecosystems because they colonise and decompose dead wood, facilitating colonisation by later species. Here, we review the importance of intact forest ecosystems to dead wood fungi, as well as trends in their diversity research and challenges in conservation. Saproxylic communities are sensitive to transition from virgin forests to managed ecosystems, since the latter often results in reduced tree diversity and the removal of their natural habitat dead wood. The impact of dead wood management can be quite significant since many saproxylic fungi are host-specific. The significance of citizen science and educational programmes for saproxylic mycology is discussed with the emphasis on the North American region. We intend to raise the awareness of the role that dead wood fungi play in forest health in order to support development of corresponding conservational programmes.