@article{fdi:010078104,
  title = {{D}iagenetic production, accumulation and sediment-water exchanges of methylmercury in contrasted sediment facies of {L}ake {T}iticaca ({B}olivia)},
  author = {{G}u{\'e}dron, {S}t{\'e}phane and {A}udry, {S}. and {A}cha, {D}. and {B}ouchet, {S}. and {P}oint, {D}avid and {C}ondom, {T}homas and {H}eredia, {C}. and {C}ampillo, {S}. and {B}aya, {P}. {A}. and {G}roleau, {A}. and {A}mice, {E}. and {A}mouroux, {D}.},
  editor = {},
  language = {{ENG}},
  abstract = {{M}onomethylmercury ({MMH}g) concentrations in aquatic biota from {L}ake {T}iticaca are elevated although the mercury ({H}g) contamination level of the lake is low. {T}he contribution of sediments to the lake {MMH}g pool remained however unclear. {I}n this work, seven cores representative of the contrasted sediments and aquatic ecotopes of {L}ake {T}iticaca were sliced and analyzed for {H}g and redox-sensitive elements ({M}n, {F}e, {N} and {S}) speciation in pore-water ({PW}) and sediment to document early diagenetic processes responsible for {MMH}g production and accumulation in {PW} during organic matter ({OM}) oxidation. {T}he highest {MMH}g concentrations (up to 12.2 ng {L}-1 and 90% of {TH}g) were found in subsurface {PW}s of the carbonate-rich sediments which cover 75% of the small basin and 20% of the large one. {I}n other sediment facies, the larger content of {OM} restricted {MMH}g production and accumulation in {PW} by sequestering {H}g in the solid phase and potentially also by decreasing its bioavailability in the {PW}. {D}iagenetically reduced {S} and {F}e played a dual role either favoring or restricting the availability of {H}g for biomethylation. {T}he calculation of theoretical diffusive fluxes suggests that {L}ake {T}iticaca bottom sediments are a net source of {MMH}g, accounting for more than one third of the daily {MMH}g accumulated in the water column of the {L}ago {M}enor. {W}e suggest that in the context of rising anthropogenic pressure, the enhancement of eutrophication in high altitude {A}ltiplano lakes may increase these {MMH}g effluxes into the water column and favor its accumulation in water and biota.},
  keywords = {{M}ethylmercury ; {L}ake sediment ; {E}arly diagenesis ; {H}igh altitude ecosystem ; {D}iffusive fluxes ; {BOLIVIE} ; {TITICACA} {LAC}},
  booktitle = {},
  journal = {{S}cience of the {T}otal {E}nvironment},
  volume = {723},
  numero = {},
  pages = {art. 138088 [ 14 p.]},
  ISSN = {0048-9697},
  year = {2020},
  DOI = {10.1016/j.scitotenv.2020.138088},
  URL = {https://www.documentation.ird.fr/hor/fdi:010078104},
}