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author Xie, Sitan
Lipp, Julius S
Wegener, Gunter
Ferdelman, Timothy G
Hinrichs, Kai-Uwe
author_facet Xie, Sitan
Lipp, Julius S
Wegener, Gunter
Ferdelman, Timothy G
Hinrichs, Kai-Uwe
collection Datos científicos de ciencias marinas y ambientales
contents An experiment was conceived in which we monitored degradation of GlcDGD. Independent of the fate of the [14C]glucosyl headgroup after hydrolysis from the glycerol backbone, the 14C enters the aqueous or gas phase whereas the intact lipid is insoluble and remains in the sediment phase. Total degradation of GlcDGD then is obtained by combining the increase of radioactivity in the aqueous and gaseous phases. We chose two different sediment to perform this experiment. One is from microbially actie surface sediment sampled in February 2010 from the upper tidal flat of the German Wadden Sea near Wremen (53° 38' 0N, 8° 29' 30E). The other one is deep subsurface sediments recovered from northern Cascadia Margin during Integrated Ocean Drilling Program Expedition 311 [site U1326, 138.2 meters below seafloor (mbsf), in situ temperature 20 °C, water depth 1,828 m. We performed both alive and killed control experiments for comparison. Surface and subsurface sediment slurry were incubated in the dark at in situ temperature, 4 °C and 20 °C for 300 d, respectively. The sterilized slurry was stored at 20 °C. All incubations were carried out under N2 headspace to ensure anaerobic conditions. The sampling frequency was high during the first half-month, i.e., after 1, 2, 7, and 14 d; thereafter, the sediment slurry was sampled every 2 months. At each time point, samples were taken in triplicate for radioactivity measurements. After 300 d of incubation, no significant changes of radioactivity in the aqueous phase were detected. This may be the result of either the rapid turnover of released [14C] glucose or the relatively high limit of detection caused by the slight solubility (equivalent to 2% of initial radioactivity) of GlcDGD in water. Therefore, total degradation of GlcDGD in the dataset was calculated by combining radioactivity of DIC, CH4, and CO2, leading to a minimum estimate.
format Dataset Open Access
id pangaea_https___doi_org_10_1594_PANGAEA_815450
institution PANGAEA
language en
publishDate 2013
publisher PANGAEA
record_format pangaea
spellingShingle Degradation of [14C]GlcDGD in the marine sediment by monitoring radioactivity in the aqueous and gas phase using liquid scintillation counting (LSC) techniques
Xie, Sitan
Lipp, Julius S
Wegener, Gunter
Ferdelman, Timothy G
Hinrichs, Kai-Uwe
311-U1326C; Cascadia Margin Gas Hydrates; Center for Marine Environmental Sciences; Comment; DATE/TIME; DEPTH, sediment/rock; DRILL; Drilling/drill rig; Event label; Exp311; German_Wadden_Sea_2010; German Bight, North Sea; Incubation duration; Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP; Joides Resolution; Liquid scintillation counter (TR-2900, Canberra-Packard); MARUM; MULT; Multiple investigations; Radioactivity; Sample, optional label/labor no; Temperature, technical
An experiment was conceived in which we monitored degradation of GlcDGD. Independent of the fate of the [14C]glucosyl headgroup after hydrolysis from the glycerol backbone, the 14C enters the aqueous or gas phase whereas the intact lipid is insoluble and remains in the sediment phase. Total degradation of GlcDGD then is obtained by combining the increase of radioactivity in the aqueous and gaseous phases. We chose two different sediment to perform this experiment. One is from microbially actie surface sediment sampled in February 2010 from the upper tidal flat of the German Wadden Sea near Wremen (53° 38' 0N, 8° 29' 30E). The other one is deep subsurface sediments recovered from northern Cascadia Margin during Integrated Ocean Drilling Program Expedition 311 [site U1326, 138.2 meters below seafloor (mbsf), in situ temperature 20 °C, water depth 1,828 m. We performed both alive and killed control experiments for comparison. Surface and subsurface sediment slurry were incubated in the dark at in situ temperature, 4 °C and 20 °C for 300 d, respectively. The sterilized slurry was stored at 20 °C. All incubations were carried out under N2 headspace to ensure anaerobic conditions. The sampling frequency was high during the first half-month, i.e., after 1, 2, 7, and 14 d; thereafter, the sediment slurry was sampled every 2 months. At each time point, samples were taken in triplicate for radioactivity measurements. After 300 d of incubation, no significant changes of radioactivity in the aqueous phase were detected. This may be the result of either the rapid turnover of released [14C] glucose or the relatively high limit of detection caused by the slight solubility (equivalent to 2% of initial radioactivity) of GlcDGD in water. Therefore, total degradation of GlcDGD in the dataset was calculated by combining radioactivity of DIC, CH4, and CO2, leading to a minimum estimate.
title Degradation of [14C]GlcDGD in the marine sediment by monitoring radioactivity in the aqueous and gas phase using liquid scintillation counting (LSC) techniques
topic 311-U1326C; Cascadia Margin Gas Hydrates; Center for Marine Environmental Sciences; Comment; DATE/TIME; DEPTH, sediment/rock; DRILL; Drilling/drill rig; Event label; Exp311; German_Wadden_Sea_2010; German Bight, North Sea; Incubation duration; Integrated Ocean Drilling Program / International Ocean Discovery Program; IODP; Joides Resolution; Liquid scintillation counter (TR-2900, Canberra-Packard); MARUM; MULT; Multiple investigations; Radioactivity; Sample, optional label/labor no; Temperature, technical
url https://doi.org/10.1594/PANGAEA.815450