A cross-seasonal comparison of active and total bacterial community composition in Arctic tundra soil using bromodeoxyuridine labeling

► In shrub tundra soil, winter- and summer-active bacterial communities differed. ► Active members of shrub bacterial community were rare in the total community. ► More bacteria in tussock tundra were active in both summer and winter. ► In tussock tundra, there was more overlap between the active and total community. ► BrdU-labeling highlights rare individuals in a community.