@article{fdi:010072680,
  title = {{C}arbon dioxide emissions from the flat bottom and shallow {N}am {T}heun 2 {R}eservoir : drawdown area as a neglected pathway to the atmosphere},
  author = {{D}eshmukh, {C}. and {G}u{\'e}rin, {F}r{\'e}d{\'e}ric and {V}ongkhamsao, {A}. and {P}ighini, {S}. and {O}udone, {P}. and {S}opraseuth, {S}. and {G}odon, {A}. and {R}ode, {W}. and {G}uedant, {P}. and {O}liva, {P}. and {A}udry, {S}. and {Z}ouiten, {C}. and {G}aly-{L}acaux, {C}. and {R}obain, {H}enri and {R}ibolzi, {O}livier and {K}ansal, {A}. and {C}hanudet, {V}. and {D}escloux, {S}. and {S}erca, {D}.},
  editor = {},
  language = {{ENG}},
  abstract = {{F}reshwater reservoirs are a significant source of {CO}2 to the atmosphere. {CO}2 is known to be emitted at the reservoir surface by diffusion at the air-water interface and downstream of dams or powerhouses by degassing and along the river course. {I}n this study, we quantified total {CO}2 emissions from the {N}am {T}heun 2 {R}eservoir ({L}ao {PDR}) in the {M}ekong {R}iver watershed. {T}he study started in {M}ay 2009, less than a year after flooding and just a few months after the maximum level was first reached and lasted until the end of 2013. {W}e tested the hypothesis that soils from the draw-down area would be a significant contributor to the total {CO}2 emissions. {T}otal inorganic carbon, dissolved and particulate organic carbon and {CO}2 concentrations were measured in 4 pristine rivers of the {N}am {T}heun watershed, at 9 stations in the reservoir (vertical profiles) and at 16 stations downstream of the monomictic reservoir on a weekly to monthly basis. {CO}2 bubbling was estimated during five field campaigns between 2009 and 2011 and on a weekly monitoring, covering water depths ranging from 0.4 to 16 m and various types of flooded ecosystems in 2012 and 2013. {T}hree field campaigns in 2010, 2011 and 2013 were dedicated to the soils description in 21 plots and the quantification of soil {CO}2 emissions from the drawdown area. {O}n this basis, we calculated total {CO}2 emissions from the reservoir and carbon inputs from the tributaries. {W}e confirm the importance of the flooded stock of organic matter as a source of carbon ({C}) fuelling emissions. {W}e show that the drawdown area contributes, depending on the year, from 40 to 75% of total annual gross emissions in this flat and shallow reservoir. {S}ince the {CO}2 emissions from the drawdown zone are almost constant throughout the years, the large interannual variations result from the significant decrease in diffusive fluxes and downstream emissions between 2010 and 2013. {T}his overlooked pathway in terms of gross emissions would require an in-depth evaluation for the soil organic matter and vegetation dynamics to evaluate the actual contribution of this area in terms of net modification of gas exchange in the footprint of the reservoir, and how it could evolve in the future.},
  keywords = {{LAOS} ; {MEKONG} {COURS} {D}'{EAU}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {15},
  numero = {6},
  pages = {1775--1794},
  ISSN = {1726-4170},
  year = {2018},
  DOI = {10.5194/bg-15-1775-2018},
  URL = {https://www.documentation.ird.fr/hor/fdi:010072680},
}