Microbial Diversity in Young Volcanic Soils

Soil is an integral part of the global carbon cycle with a high capacity for storing carbon. Understanding the factors influencing carbon respiration is required to identify potential responses to changing climate. Icelandic soils have characteristics allowing for unique studies of soil formation and carbon respiration, but has been little studied with regard to microbial communities. Analysis of the distribution of 16S and 18S rRNA genes from bacteria and eukaryotes was done to compare microbial community composition between andisols and vitrisols. An experiment with samples representing four soil depths (0-5cm, 5- 10cm, 10-20cm, and 20-30cm), were incubated for 50 days, with replicates in 3 different temperature regimes (5°C, 15°C, and 25°C). Genetic material was extracted at 5, 12, and 50 days, with SSU rRNA genes subsequently amplified and sequenced. Greater microbial richness was found in vitrisols than andisols, and richness decreased with depth for both soil types. Taxonomic assignment of bacteria showed high proportions of the phyla Proteobacteria and Actinobacteriota in both soil types. The change in abundance of taxa over the incubation experiment can be used to identify changes due to rewetting of dry- stored soils, and potentially r- or k-selected taxa and their response to increased temperature. This study of microbial communities can be linked to carbon respiration and soil properties to better understand the effect of microbes on soil processes. This information can then guide discussions regarding greenhouse gas emission, soil carbon storage potential, soil formation and development, and modeling of carbon flux from young volcanic soils.

Author dc:creator

• Tanner Tobiasson Thelmudóttir 1993-

Contributors dc:contributor

• Háskóli Íslands

• Umhverfis- og auðlindafræði

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/1946/38484

OAI identifier oai:identifier

oai:skemman.is:1946/38484