Br/Cl, I/Cl and chlorine isotopic compositions of pore water in shallow sediments: implications for the fluid sources in the Dongsha area, northern South China Sea

2017 ◽  
Vol 36 (4) ◽  
pp. 31-36 ◽  
Author(s):  
Yanping Li ◽  
Shaoyong Jiang ◽  
Tao Yang
Keyword(s):  
South China Sea ◽  
Pore Water ◽  
South China ◽  
Northern South China Sea ◽  
China Sea ◽  
Isotopic Compositions ◽  
Shallow Sediments ◽  
Fluid Sources

scholarly journals Thaumarchaeotal Signature Gene Distribution in Sediments of the Northern South China Sea: an Indicator of the Metabolic Intersection of the Marine Carbon, Nitrogen, and Phosphorus Cycles?

2013 ◽  
Vol 79 (7) ◽  
pp. 2137-2147 ◽  
Author(s):  
Hongyue Dang ◽  
Haixia Zhou ◽  
Jinying Yang ◽  
Huangmin Ge ◽  
Nianzhi Jiao ◽  
...  
Keyword(s):  
Community Structure ◽  
South China Sea ◽  
Pore Water ◽  
Marine Sediments ◽  
South China ◽  
Carbon Fixation ◽  
Northern South China Sea ◽  
Nitrogen And Phosphorus ◽  
China Sea ◽  
Lipid Biomarker

ABSTRACTThaumarchaeota are abundant and active in marine waters, where they contribute to aerobic ammonia oxidation and light-independent carbon fixation. The ecological function of thaumarchaeota in marine sediments, however, has rarely been investigated, even though marine sediments constitute the majority of the Earth's surface. Thaumarchaeota in the upper layer of sediments may contribute significantly to the reservoir of nitrogen oxides in ocean waters and thus to productivity, including the assimilation of carbon. We tested this hypothesis in the northern South China Sea (nSCS), a section of a large oligotrophic marginal sea with limited influx of nutrients, including nitrogen, by investigating the diversity, abundance, community structure, and spatial distribution of thaumarchaeotal signatures in surface sediments. Quantitative real-time PCR using primers designed to detect 16S rRNA andamoAgenes in sediment community DNA revealed a significantly higher abundance of pertinent thaumarchaeotal than betaproteobacterial genes. This finding correlates with high levels ofhcdgenes, a signature of thaumarchaeotal autotrophic carbon fixation. Thaumarchaeol, a signature lipid biomarker for thaumarchaeota, constituted the majority of archaeal lipids in marine sediments. Sediment temperature and organic P and silt contents were identified as key environmental factors shaping the community structure and distribution of the monitored thaumarchaeotalamoAgenes. When the pore water PO43−concentration was controlled for via partial-correlation analysis, thaumarchaeotalamoAgene abundance significantly correlated with the sediment pore water NO2−concentration, suggesting that theamoA-bearing thaumarchaeota contribute to nitrite production. Statistical analyses also suggest that thaumarchaeotal metabolism could serve as a pivotal intersection of the carbon, nitrogen, and phosphorus cycles in marine sediments.

Sign in / Sign up

Export Citation Format

Share Document