Resistance of the Archaeal Community to a Severe Disturbance in an Extreme Alkaline Saline Soil.

An extreme disturbance, i.e. a 1-day chloroform fumigation, had a strong impact on the bacterial community structure in an extreme saline alkaline soil, but how Archaea respond to such an event is largely unknown. Three alkaline saline soils with electrolytic conductivity (EC) between 139 and 157 dS m- 1 and pH 10.0-10.3 were chloroform fumigated for one day and the recovery of the archaeal community determined after 1, 5 and 10 days, while an unfumigated soil served as control. Six archaeal phyla dominated by Candidatus Halobacterota (relative abundance 96.9%) were detected, while Natronorubrum dominated in the unfumigated (9.7%) and fumigated extreme alkaline saline soil (8.9%). Fumigation and time had a significant effect on the archaeal community structure. Some archaeal groups, e.g. Halovarius sp., were strongly affected by fumigation most accentuated on day 1 and 5. It was found that chloroform fumigation had only a limited and mostly a short time effect on the archaeal groups which demonstrated their resistance to a severe disturbance in extreme adverse conditions.