Organic matter quantity and source affects microbial community structure and function following volcanic eruption on Kasatochi Island, Alaska

Environmental Microbiology
By: , and 

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Abstract

In August 2008, Kasatochi volcano erupted and buried a small island in pyroclastic deposits and fine ash; since then, microbes, plants and birds have begun to re-colonize the initially sterile surface. Five years post-eruption, bacterial 16S rRNA gene and fungal internal transcribed spacer (ITS) copy numbers and extracellular enzyme activity (EEA) potentials were one to two orders of magnitude greater in pyroclastic materials with organic matter (OM) inputs relative to those without, despite minimal accumulation of OM (< 0.2%C). When normalized by OM levels, post-eruptive surfaces with OM inputs had the highest β-glucosidase, phosphatase, NAGase and cellobiohydrolase activities, and had microbial population sizes approaching those in reference soils. In contrast, the strongest factor determining bacterial community composition was the dominance of plants versus birds as OM input vectors. Although soil pH ranged from 3.9 to 7.0, and %C ranged 100×, differentiation between plant- and bird-associated microbial communities suggested that cell dispersal or nutrient availability are more likely drivers of assembly than pH or OM content. This study exemplifies the complex relationship between microbial cell dispersal, soil geochemistry, and microbial structure and function; and illustrates the potential for soil microbiota to be resilient to disturbance.

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Additional publication details

Publication type Article
Publication Subtype Journal Article
Title Organic matter quantity and source affects microbial community structure and function following volcanic eruption on Kasatochi Island, Alaska
Series title Environmental Microbiology
DOI 10.1111/1462-2920.12924
Volume 18
Issue 1
Year Published 2016
Language English
Publisher Wiley
Contributing office(s) Alaska Science Center Biology WTEB
Description 13 p.
First page 146
Last page 158
Country United States
State Alaska
Other Geospatial Kasatochi Island
Online Only (Y/N) N
Additional Online Files (Y/N) N