@article{fdi:010062328,
  title = {{C}omposition changes of eroded carbon at different spatial scales in a tropical watershed suggest enrichment of degraded material during transport},
  author = {{R}umpel, {C}. and {C}haplot, {V}incent and {C}iais, {P}. and {C}habbi, {A}. and {B}ouahom, {B}. and {V}alentin, {C}hristian},
  editor = {},
  language = {{ENG}},
  abstract = {{I}n order to assess whether eroded carbon is a net source or sink of atmospheric {CO}2, characterisation of the chemical composition and residence time of eroded organic matter ({EOM}) at the landscape level is needed. {T}his information is crucial to evaluate (1) how fast {EOM} can be decomposed by soil microbes during its lateral transport and (2) its impact at deposition sites. {T}his study considers a continuum of scales to measure the composition of {EOM} across a steep hillslope landscape of the {M}ekong basin with intense erosion. {W}e sampled suspended sediments eroded during rainfall events from runoff plots (1 and 2.5 m(2)) and the outlets of four nested watersheds (0.6 x 10(4) to 1 x 10(7) m(2)). {H}ere we show that changes in the chemical composition of {EOM} (measured by nuclear magnetic resonance spectroscopy) and in its {C}-13 and {N}-15 isotope composition from plot scale through to landscape scale provide consistent evidence for enrichment of more decomposed {EOM} across distances of 10 km. {B}etween individual soil units (1 m(2)) to a small watershed (10(7) m(2)), the observed 28% decrease of the {C} / {N} ratio, the enrichment of {C}-13 and {N}-15 isotopes as well as {O}-alkyl {C} in {EOM} is of similar magnitude as changes recorded with depth in soil profiles due to soil organic matter "vertical" decomposition. {R}adiocarbon measurements indicated ageing of {EOM} from the plot to the watershed scale. {T}herefore transport of {EOM} may lead to enrichment of stabilised soil organic matter compounds, eventually being subject to export from the watershed.},
  keywords = {{LAOS} ; {MEKONG} {BASSIN}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {11},
  numero = {12},
  pages = {3299--3305},
  ISSN = {1726-4170},
  year = {2014},
  DOI = {10.5194/bg-11-3299-2014},
  URL = {https://www.documentation.ird.fr/hor/fdi:010062328},
}