Coupling between bacterial community composition and allochthonous organic matter in a sub-arctic estuary
(English)Manuscript (preprint) (Other academic)
Climate change is expected to cause increased precipitation in boreal and subarctic zones, leading to increased runoff of allochthonous dissolved organic matter (ADOM) from land to the sea. ADOM has been shown to be a major driver of bacterioplankton production in a sub-arctic estuary in the northern Baltic Sea, the Råne estuary. By using a network approach we here analyzed how the bacterial community is affected by ADOM and other environmental factors in the same estuary. β-proteobacteria were observed to be dominant in spring when the river runoff and the ADOM concentrations were high. Planctomycetes and Verrucomicrobia become more abundant later during the summer when the ADOM discharge was low. The diversity and evenness in the bacterioplankton community increased as the runoff decreased during the summer. During this period Verrucomicrobia, β-proteobacteria, Bacteriodetes, γ-proteobacteria and Planctomycetes became more abundant. Overall more complex population interactions were established in summer than in spring. β-proteobacteria and Bacteriodetes formed clusters, showing similar responses to different environmental factors, which suggest a functional connection between these groups. The bacterial community consisted of as much as ~60% of generalists, which reflected the large variation of the environmental conditions in the estuary.
Bacterial community structure; allochthonous organic matter; bacterioplankton ecological function; bacterial diversity; bacterial network; environmental changes; Baltic Sea estuary.
Research subject Earth Sciences with Specialization Environmental Analysis; Microbiology
IdentifiersURN: urn:nbn:se:umu:diva-117976OAI: oai:DiVA.org:umu-117976DiVA: diva2:910229
FunderEcosystem dynamics in the Baltic Sea in a changing climate perspective - ECOCHANGE