A preliminary estimate of organic carbon transport by the Ayeyarwady (Irrawaddy) and Thanlwin (Salween) Rivers of Myanmar

Bird, M.I., Robinson, R.A.J., Winn Oo, N., Maung Aye, M., Lu, X.X., Higgitt, D.L., Swe, A., Tun, T., Lhaing Win, S., Sandar Aye, K., Mi Mi Win, K., and Hoey, T.B. (2008) A preliminary estimate of organic carbon transport by the Ayeyarwady (Irrawaddy) and Thanlwin (Salween) Rivers of Myanmar. Quaternary International, 186 (1). pp. 113-122.

[img] PDF (Published Version) - Published Version
Restricted to Repository staff only

View at Publisher Website: http://dx.doi.org/10.1016/j.quaint.2007....
 
40
1


Abstract

We report results of a preliminary study of particulate and dissolved organic carbon transport in the Ayeyarwady and Thanlwin Rivers of Myanmar, based on 52 suspended sediment samples and 9 water samples collected during conditions of low and high flow in 2005 and 2006. The Ayeyarwady transports 2.2–4.3 MtC/yr as POC with a weighted average δ13C value of -24.8‰, while the Thanlwin transports an additional 2.4–3.4 MtC/yr with a δ13C value of -25.3‰. In addition, the Ayeyarwady transports ~0.9Mt/yr, and the Thanlwin ~0.23Mt/yr, of DOC with a δ13C value of -26.2‰ and -27.1‰, respectively. The Ayeyarwady and Thanlwin catchments adjoin each other, debouching into the Indian Ocean over a length scale similar to the deltas of the Ganges–Brahmaputra or the Amazon. Therefore, the Ayeyarwady and Thanlwin rivers should be considered a single point source contributing to the global ocean.

This combined river system transports 5.7–8.8 MtC/yr of organic carbon, suggesting that it may be the second largest point source of organic carbon to the global ocean after the Amazon. The implied organic carbon yield from the catchments is 8.4–12.9 t/km2/yr, which is clearly amongst the highest in the world among rivers of similarly large size. The high organic carbon yields are likely to be the result of (i) a strongly monsoonal climate, (ii) the large area of highly productive forest present on steep slopes in a region of active tectonism, and (iii) the comparatively small area of floodplain in the catchments.

Item ID: 18840
Item Type: Article (Research - C1)
ISSN: 1873-4553
Date Deposited: 03 Oct 2011 05:00
FoR Codes: 04 EARTH SCIENCES > 0406 Physical Geography and Environmental Geoscience > 040608 Surfacewater Hydrology @ 50%
04 EARTH SCIENCES > 0402 Geochemistry > 040203 Isotope Geochemistry @ 50%
SEO Codes: 96 ENVIRONMENT > 9611 Physical and Chemical Conditions of Water > 961103 Physical and Chemical Conditions of Water in Fresh, Ground and Surface Water Environments (excl. Urban and @ 100%
Downloads: Total: 1
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page