当前位置： SCI文献检索 > Frontiers in Microbiology期刊下所有文献 > The Effect of Increased Loads of Dissolved Organic Matter on Estuarine Microbial Community Composition and Function.

The Effect of Increased Loads of Dissolved Organic Matter on Estuarine Microbial Community Composition and Function.

Abstract：

:Increased river loads are projected as one of the major consequences of climate change in the northern hemisphere, leading to elevated inputs of riverine dissolved organic matter (DOM) and inorganic nutrients to coastal ecosystems. The objective of this study was to investigate the effects of elevated DOM on a coastal pelagic food web from the coastal northern Baltic Sea, in a 32-day mesocosm experiment. In particular, the study addresses the response of bacterioplankton to differences in character and composition of supplied DOM. The supplied DOM differed in stoichiometry and quality and had pronounced effects on the recipient bacterioplankton, driving compositional changes in response to DOM type. The shifts in bacterioplankton community composition were especially driven by the proliferation of Bacteroidetes, Gemmatimonadetes, Planctomycetes, and Alpha- and Betaproteobacteria populations. The DOM additions stimulated protease activity and a release of inorganic nutrients, suggesting that DOM was actively processed. However, no difference between DOM types was detected in these functions despite different community compositions. Extensive release of re-mineralized carbon, nitrogen and phosphorus was associated with the bacterial processing, corresponding to 25-85% of the supplied DOM. The DOM additions had a negative effect on phytoplankton with decreased Chl a and biomass, particularly during the first half of the experiment. However, the accumulating nutrients likely stimulated phytoplankton biomass which was observed to increase towards the end of the experiment. This suggests that the nutrient access partially outweighed the negative effect of increased light attenuation by accumulating DOM. Taken together, our experimental data suggest that parts of the future elevated riverine DOM supply to the Baltic Sea will be efficiently mineralized by microbes. This will have consequences for bacterioplankton and phytoplankton community composition and function, and significantly affect nutrient biogeochemistry.

journal_name

Front Microbiol

journal_title

Frontiers in microbiology

authors

Traving SJ,Rowe O,Jakobsen NM,Sørensen H,Dinasquet J,Stedmon CA,Andersson A,Riemann L

doi

10.3389/fmicb.2017.00351

subject

Has Abstract

pub_date

2017-03-09 00:00:00

pages

351

issn

1664-302X

journal_volume

pub_type

杂志文章

在线工具

The Effect of Increased Loads of Dissolved Organic Matter on Estuarine Microbial Community Composition and Function.