# Fauna and Ecology of Macromycetes (Basidiomycota) in the Arctic Tree and Shrub Ecosystems of Central Siberia

## TL;DR

This study explores the diversity and ecological roles of fungi in Arctic tree and shrub ecosystems in Central Siberia, revealing insights into their biodiversity and function in permafrost regions.

## Contribution

The study provides a detailed taxonomic and ecological analysis of macromycetes in under-researched Arctic ecosystems of Central Siberia.

## Key findings

- Seventy species of macromycetes were identified, with mycorrhizal and wood decay fungi dominating (71%).
- Fungal decomposers are prevalent in tundra areas due to the lack of woody substrates.
- The taxonomic and ecological structure of Basidiomycota in Arctic ecosystems resembles that of taiga and temperate forests.

## Abstract

The Arctic tree and shrub ecosystems of Central Siberia are distinctive in their ability to perform crucial biosphere functions. However, such forests have been the subject of relatively limited research. The understanding of the dynamics of these forests, including their composition and structure, is of significant relevance for the conservation of permafrost ecosystem biodiversity. Nevertheless, the species composition of the mycobiota of this region remain under investigation. The aim of the present study is to determine the macromycetes diversity in the main ecotopes of the Krasnoyarsk Arctic (Norilsk). An understanding of the ecological attributes of macromycetes within these ecosystems is essential for understanding of the decomposition of organic matter, the absorption of nutrients by trees and shrubs, and other fundamental ecological processes. Moreover, basidiomycetes may be utilized as indicator species in ecological studies.

The research was aimed at studying the taxonomic diversity, habitat specialization, and trophic characteristics of mycobiota, including Basidiomycota, in the northern ecosystems of the Krasnoyarsk Krai (Central Siberia) near Norilsk. Larch forests and woodlands in the Siberian permafrost zone are distinctive and Basidiomycota, as a component of these ecosystems, plays an essential role in their functioning. Currently, there is a paucity of information about this group in Arctic ecosystems, both in terms of floristic and ecological aspects. Seventy species of macromycetes belonging to different trophic groups were discovered and identified. Only 15% of species occur regularly, while most species are found rarely or only once. The identified species belong to 44 genera, 25 families, and 8 orders, which are included in the class Agaricomycetes. The leading families in terms of the number of species are Russulaceae, Polyporaceae, Tricholomataceae, Suillaceae, Strophariaceae, and Cortinariaceae. Mycorrhizal fungi and wood decay fungi dominate the structure of mycobiota of the study area (the total share is 71%). The rest of the species (29%) are fungal decomposers inhabiting plant litter, the forest floor, and humus. The largest number of species occur in forest ecosystems, which are dominated by mycorrhizal and wood decay fungi (up to 70%), which are trophically associated with woody plants and debris. The fungal decomposers inhabiting plant litter, the forest floor, and humus dominate (about 80%) in the species composition of tundra, where, in the absence of woody substrate, wood decay fungi have not been found at all. The species richness of tree and shrub Arctic ecosystems is low, yet the taxonomical and ecological structure of Basidiomycota is similar to that observed in taiga and temperate forests. These data permit a more comprehensive description of the biodiversity of the Arctic and may prove useful in studying biological processes in these ecosystems.