@article{fdi:010062422,
  title = {{S}patial and temporal variability of {B}e-7 and {P}b-210 wet deposition during four successive monsoon storms in a catchment of northern {L}aos},
  author = {{G}ourdin, {E}. and {E}vrard, {O}. and {H}uon, {S}. and {R}eyss, {J}. {L}. and {R}ibolzi, {O}livier and {B}ariac, {T}. and {S}engtaheuanghoung, {O}. and {A}yrault, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{F}allout radionuclides {B}e-7 and {P}b-210 have been identified as potentially relevant temporal tracers for studying soil particles dynamics (surface vs. subsurface sources contribution; remobilization of inchannel sediment) during erosive events in river catchments. {A}n increasing number of studies compared {B}e-7: {P}b-210 activity ratio in rainwater and sediment to estimate percentages of freshly eroded particles. {H}owever, the lack of data regarding the spatial and temporal variability of radionuclide wet deposition during individual storms has been identified as one of the main gaps in these estimates. {I}n order to determine these key parameters, rainwater samples were collected at three stations during four storms that occurred at the beginning of the monsoon ({J}une 2013) in the {H}ouay {X}on mountainous catchment in northern {L}aos. {R}ainwater {B}e-7 and {P}b-210 activities measured using very low background hyperpure {G}ermanium detectors ranged from 0.05 to 1.72 {B}q {L}-1 and 0.02 to 0.26 {B}q {L}-1, respectively. {W}ater 8180 were determined on the same samples. {T}otal rainfall amount of the four sampled storms ranged from 4.8 to 26.4 mm (51 mm in total) at the time-fractionated collection point. {C}orresponding cumulative 78e and 210{P}b wet depositions during the sampling period were 17.6 and 2.9 {B}q m(-2), respectively. {T}he 7{B}e: 210{P}b activity ratio varied (1) in space from 6 to 9 for daily deposition and (2) in time from 3 to 12 for samples successively collected. {I}ntra-event evolution of rainwater 7{B}e and 210{P}b activities as well as 8180 highlighted the progressive depletion of local infra-cloud atmosphere radionuclide stock with time (washout), which remains consistent with a {R}aleigh-type distillation process for water vapour. {I}ntra-storm ratio increasing with time showed the increasing contribution of rainout scavenging. {I}mplications of such variability for soil particle labelling and erosion studies are briefly discussed and recommendations are formulated for the collection of rainwater signature in studies based on the {B}e-7: {P}b-210 ratio method, especially in tropical areas under high erosive pressure.},
  keywords = {{B}e-7 ; {P}b-210 ; {R}ainwater ; {M}onsoon storm ; {W}et deposition ; {L}ocal spatial ; temporal variability ; {LAOS}},
  booktitle = {},
  journal = {{J}ournal of {E}nvironmental {R}adioactivity},
  volume = {136},
  numero = {},
  pages = {195--205},
  ISSN = {0265-931{X}},
  year = {2014},
  DOI = {10.1016/j.jenvrad.2014.06.008},
  URL = {https://www.documentation.ird.fr/hor/fdi:010062422},
}