Not logged in
Data Publisher for Earth & Environmental Science

Endres, Sonja; Galgani, Luisa; Riebesell, Ulf; Schulz, Kai Georg; Engel, Anja; Dupont, Sam (2016): Bacteria growth, enzyme activities and TEP during KOSMOS 2011 mesocosm experiment in the Raunefjord. PANGAEA,, Supplement to: Endres, Sonja; Galgani, Luisa; Riebesell, Ulf; Schulz, Kai Georg; Engel, Anja (2014): Stimulated Bacterial Growth under Elevated pCO2: Results from an Off-Shore Mesocosm Study. PLoS ONE, 9(6), e99228,

Always quote above citation when using data! You can download the citation in several formats below.

RIS CitationBibTeX CitationShow MapGoogle Earth

Marine bacteria are the main consumers of freshly produced organic matter. Many enzymatic processes involved in the bacterial digestion of organic compounds were shown to be pH sensitive in previous studies. Due to the continuous rise in atmospheric CO2 concentration, seawater pH is presently decreasing at a rate unprecedented during the last 300 million years but the consequences for microbial physiology, organic matter cycling and marine biogeochemistry are still unresolved. We studied the effects of elevated seawater pCO2 on a natural plankton community during a large-scale mesocosm study in a Norwegian fjord. Nine Kiel Off-Shore Mesocosms for Future Ocean Simulations (KOSMOS) were adjusted to different pCO2 levels ranging initially from ca. 280 to 3000 µatm and sampled every second day for 34 days. The first phytoplankton bloom developed around day 5. On day 14, inorganic nutrients were added to the enclosed, nutrient-poor waters to stimulate a second phytoplankton bloom, which occurred around day 20. Our results indicate that marine bacteria benefit directly and indirectly from decreasing seawater pH. During the first phytoplankton bloom, 5-10% more transparent exopolymer particles were formed in the high pCO2 mesocosms. Simultaneously, the efficiency of the protein-degrading enzyme leucine aminopeptidase increased with decreasing pH resulting in up to three times higher values in the highest pCO2/lowest pH mesocosm compared to the controls. In general, total and cell-specific aminopeptidase activities were elevated under low pH conditions. The combination of enhanced enzymatic hydrolysis of organic matter and increased availability of gel particles as substrate supported up to 28% higher bacterial abundance in the high pCO2 treatments. We conclude that ocean acidification has the potential to stimulate the bacterial community and facilitate the microbial recycling of freshly produced organic matter, thus strengthening the role of the microbial loop in the surface ocean.
Latitude: 60.264500 * Longitude: 5.205500
Date/Time Start: 2011-05-07T00:00:00 * Date/Time End: 2011-06-11T00:00:00
KOSMOS_2011_Bergen (Raunefjord) * Latitude: 60.264500 * Longitude: 5.205500 * Date/Time Start: 2011-05-05T00:00:00 * Date/Time End: 2011-06-05T00:00:00 * Method/Device: Mesocosm experiment (MESO)
#NameShort NameUnitPrincipal InvestigatorMethod/DeviceComment
1DATE/TIMEDate/TimeEndres, SonjaGeocode
2Day of experimentDOEdayEndres, Sonja
3Sample code/labelSample labelEndres, Sonja
4Abundance per volumeAbund v#/mlEndres, SonjaBacterial abundance
5Transparent exopolymer particles as Gum Xanthan equivalents per volumeTEPµg Xeq/lEndres, Sonja
6Transparent exopolymer particles as Gum Xanthan equivalents per volume, std devTEP std dev±Endres, Sonja
7Leucine aminopeptidase activityLeu aminopepnmol/l/hEndres, SonjaTotal LAP activity (Vmax)
8pHpHEndres, Sonja
9Chlorophyll aChl aµg/lEndres, Sonja
2053 data points

Download Data

Download dataset as tab-delimited text (use the following character encoding: )

View dataset as HTML (shows only first 2000 rows)