Control of acid polysaccharide production and234Th and POC export fluxes by marine organisms
| Autor: | Peter H. Santschi, Laodong Guo, Chin-Chang Hung, Nicolas Alvarado-Quiroz, Gary E. Schultz, Jay Pinckney, Ian D. Walsh |
|---|---|
| Rok vydání: | 2003 |
| Předmět: |
0106 biological sciences
Total organic carbon chemistry.chemical_classification 010504 meteorology & atmospheric sciences biology 010604 marine biology & hydrobiology Biological pump Particulates biology.organism_classification Polysaccharide 01 natural sciences Geophysics Oceanography Flux (metallurgy) Algae chemistry 13. Climate action Environmental chemistry Warm core ring General Earth and Planetary Sciences 14. Life underwater 0105 earth and related environmental sciences Marine snow |
| Zdroj: | Geophysical Research Letters. 30 |
| ISSN: | 0094-8276 |
| DOI: | 10.1029/2002gl016046 |
| Popis: | [1] Ratios of particulate organic carbon (POC) to particulate 234Th activities (POC/234Th) in the ocean are used to determine the POC export flux, and thus, the power of the biological pump. In order to understand the main reasons why this ratio frequently varies as a function of depth, size, and kind (suspended vs. sinking particles), we measured vertical profiles in a cold core ring and warm core ring in the Gulf of Mexico in May 2001. Here we show that particulate 234Th/POC ratios in the Gulf of Mexico are positively correlated to the content of different Th(IV)-binding polysaccharide fractions (uronic acids, total acid polysaccharides, total polysaccharides) in both suspended and sinking particles as well as to prymnesiophyte abundance, but negatively correlated to bacterial production. Variations in acid polysaccharide compounds, produced by both algae and bacteria, but degraded only by bacteria, can account for observed variations in POC/234Th ratios seen in the ocean. |
| Databáze: | OpenAIRE |
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