Association of a Specific Algal Group with Methylmercury Accumulation in Periphyton of a Tropical High-Altitude Andean Lake

• Published in: Archives of environmental contamination and toxicology Vol. 72; no. 1; pp. 1 - 10
• Main Authors: Lanza, William G., Achá, Darío, Point, David, Masbou, Jeremy, Alanoca, Lucia, Amouroux, David, Lazzaro, Xavier
• Format: Journal Article
• Language: English
• Published: New York Springer US 2017; Springer Nature B.V; Springer Verlag
• Subjects: Accumulation; Algae; Altitude; Aquatic ecosystems; Bacillariophyceae; Bacteria; Bioaccumulation; Biota; Bolivia; Chemical Sciences; Chlorophyll; Chlorophyta - chemistry; Chlorophyta - classification; Cyperaceae - physiology; Diatoms - chemistry; Diatoms - classification; Dinoflagellida - chemistry; Dinoflagellida - classification; Earth and Environmental Science; Ecotoxicology; Environment; Environmental Chemistry; Environmental Health; Environmental Monitoring; Food chains; Lakes; Magnoliopsida - physiology; Mercury; Methylmercury; Methylmercury Compounds - metabolism; Microalgae - chemistry; Microalgae - classification; Mining; Monitoring/Environmental Analysis; Myriophyllum; Oedogonium; Plankton; Pollution; Polyethylene; Regression analysis; Schoenoplectus californicus; Soil Science & Conservation; Sulfate reduction; Water Pollutants, Chemical - metabolism; Bolivia; Alga Abundance; Filamentous Green Alga; Diatom Abundance; MeHg Concentration; Algal Group
• ISSN: 0090-4341; 1432-0703
• DOI: 10.1007/s00244-016-0324-2

Periphyton relevance for methylmercury (MeHg) production and accumulation are now well known in aquatic ecosystems. Sulfate-reducing bacteria and other microbial groups were identified as the main MeHg producers, but the effect of periphyton algae on the accumulation and transfer of MeHg to the food web remains little studied. Here we investigated the role of specific groups of algae on MeHg accumulation in the periphyton of
Schoenoplectus californicus
ssp. (Totora) and
Myriophyllum
sp. in Uru Uru, a tropical high-altitude Bolivian lake with substantial fishing and mining activities accruing around it. MeHg concentrations were most strongly related to the cell abundance of the Chlorophyte genus
Oedogonium
(
r
2
 = 0.783,
p
 = 0.0126) and to no other specific genus despite the presence of other 34 genera identified. MeHg was also related to total chlorophyll-a (total algae) (
r
2
 = 0.675,
p
 = 0.0459), but relations were more significant with chlorophyte cell numbers, chlorophyll-b (chlorophytes), and chlorophyll-c (diatoms and dinoflagellates) (
r
2
 = 0.72,
p
 = 0.028,
r
2
 = 0.744,
p
 = 0.0214, and
r
2
 = 0.766,
p
 = 0.0161 respectively). However,
Oedogonium
explains most variability of chlorophytes and chlorophyll-c (
r
2
 = 0.856,
p
 = < 0.001 and
r
2
 = 0.619,
p
 = 0.002, respectively), suggesting it is the most influential group for MeHg accumulation and periphyton algae composition at this particular location and given time.