Líffræðifélag Íslands - biologia.is
Líffræðiráðstefnan 2023

Microbial communities and functionality in degraded tundra soil

Höfundar / Authors: Arna Björt Ólafsdóttir (1), Gertrude Akello (2), Ólafur Sigmar Andrésson (1) , Isabel C Barrio (3), Denis Warshan (4), Ingibjörg Svala Jónsdóttir (1).

Starfsvettvangur / Affiliations: 1. Department of Life and Environmental Sciences, University of Iceland, 2. Kyambogo University, Kampala, 3. Agricultural University of Iceland, 4. deCODE genetics.

Kynnir / Presenter: Arna Björt Ólafsdóttir

In Iceland, unsustainable land use has led to severe land degradation and desertification. This study presents for the first time a characterization of the structure and function of soil microbial communities in tundra soils of contrasting stages of degradation in Iceland and shows promise in identifying degradation processes. We used shotgun metagenomic sequencing to compare microbial communities in a Betula nana heath with erosion spots and a highly degraded desert at two sites, inside and outside the active volcanic zone (Þeistareykir and Auðkúluheiði). The desert soil’s bacterial taxonomic composition (relatively more Actinobacteria), low respiration (microbial activity) and functional diversity reflected its highly degraded state. Heath soils at Þeistareykir had more abundant key ecosystem taxa of the genus Bradyrhizobium, higher taxonomic richness, microbial activity, and functional diversity compared to the heath at Auðkúluheiði, indicating that the heath in Auðkúluheiði is more degraded. Use of the trait-based framework of high yield (Y), resource acquisition (A), and stress tolerance (S) provided a more nuanced picture of the functional microbial roles in each of these soil types.