@article{fdi:010066752,
  title = {{D}iurnal variability and biogeochemical reactivity of mercury species in an extreme high-altitude lake ecosystem of the {B}olivian {A}ltiplano},
  author = {{A}lanoca, {L}. and {A}mouroux, {D}. and {M}onperrus, {M}. and {T}essier, {E}. and {G}oni, {M}. and {G}uyoneaud, {R}. and {A}cha, {D}. and {G}assie, {C}. and {A}udry, {S}. and {G}arcia, {M}. {E}. and {Q}uintanilla, {J}. and {P}oint, {D}avid},
  editor = {},
  language = {{ENG}},
  abstract = {{M}ethylation and demethylation represent major transformation pathways regulating the net production of methylmercury ({MMH}g). {V}ery few studies have documented {H}g reactivity and transformation in extreme high-altitude lake ecosystems. {M}ercury ({H}g) species concentrations ({IH}g, {MMH}g, {H}g{A} degrees, and {DMH}g) and in situ {H}g methylation ({M}) and {MMH}g demethylation ({D}) potentials were determined in water, sediment, floating organic aggregates, and periphyton compartments of a shallow productive {L}ake of the {B}olivian {A}ltiplano ({U}ru {U}ru {L}ake, 3686 m). {S}amples were collected during late dry season ({O}ctober 2010) and late wet season ({M}ay 2011) at a north ({NS}) and a south ({SS}) site of the lake, respectively. {M}ercury species concentrations exhibited significant diurnal variability as influenced by the strong diurnal biogeochemical gradients. {P}articularly high methylated mercury concentrations (0.2 to 4.5 ng {L}-1 for {MMH}g{T}) were determined in the water column evidencing important {H}g methylation in this ecosystem. {M}ethylation and {D} potentials range were, respectively, < 0.1-16.5 and < 0.2-68.3 % day(-1) and were highly variable among compartments of the lake, but always higher during the dry season. {N}et {H}g {M} indicates that the influence of urban and mining effluent ({NS}) promotes {MMH}g production in both water (up to 0.45 ng {MMH}g {L}-1 day(-1)) and sediment compartments (2.0 to 19.7 ng {MMH}g g(-1) day(-1)). {W}hile the sediment compartment appears to represent a major source of {MMH}g in this shallow ecosystem, floating organic aggregates (dry season, {SS}) and {T}otora's periphyton (wet season, {NS}) were found to act as a significant source (5.8 ng {MMH}g g(-1) day(-1)) and a sink (-2.1 ng {MMH}g g(-1) day(-1)) of {MMH}g, respectively. {T}his work demonstrates that high-altitude productive lake ecosystems can promote {MMH}g formation in various compartments supporting recent observations of high {H}g contents in fish and water birds.},
  keywords = {{M}ercury ; {B}iogeochemistry ; {A}ltiplano ; {L}ake ; {M}ethylation ; {D}emethylation ; {B}olivia ; {BOLIVIE}},
  booktitle = {},
  journal = {{E}nvironmental {S}cience and {P}ollution {R}esearch},
  volume = {23},
  numero = {7},
  pages = {6919--6933},
  ISSN = {0944-1344},
  year = {2016},
  DOI = {10.1007/s11356-015-5917-1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010066752},
}