MONITORING WATER QUALITY IN PYRENEAN HIGH ALTITUDE LAKESOlaia Liñero (1), Bastien Duval (2), Leire Kortazar (1), Andrea Romero (2), Jose Antonio Carrero (1), Emmanuel Tessier (2), Luis Ángel

Fernández (1,3), Nagore Prieto (1), Gorka Arana (1), Kepa Castro (1), Mireia Irazola (1), David Amouroux (2), Alberto de Diego (1,3)

(1) Kimika Analitikoa Saila, Euskal Herriko Unibertsitatea (UPV/EHU), Sarriena Auzoa z/g, 48940 Leioa (Basque Country); (2) Laboratoire de Chimie Analytique, Bio-Inorganique et Environnement (LCABIE), Institut desSciences Analytiques et de Physico-Chimie pour l'Environnement et les Materiaux (IPREM), UMR-5254, F-64000 Pau (France); (3) Plentziako Itsas Estazioa, Euskal Herriko Unibertsitatea (UPV/EHU), Areatza Pasealekua,48620 Plentzia (Basque Country)

SUMMARYThe REPLIM project, funded by the European Union through the INTERREG V-A, POCTEFA 2014-2020 program, is a network of scientists, managers and citizens aimed to monitor thedynamics of high mountain lakes and peat bogs and their responses to global warming and increased human pressure. In the framework of REPLIM, two of the scientific partners of theproject took part in a joint action to check if parameters like altitude and orientation, among others, have a significant effect on quality parameters of Pyrenean lake waters. Thepreliminary results obtained up to date after the analysis of the samples collected in both campaigns of 2017 (summer and autumn) are presented in this communication.

SAMPLING CAMPAINGSTwo sampling campaigns were carried out in 2017 (in summer and autumn). In each lake, triplicate sub-surface (about 0.5 m depth) water samples were collected using a 5 L GO-FLOsampler from an inflatable boat. Each sample was divided in different sub-samples for subsequent measurement of several chemical parameters (NH4

+, silicates, TOC, TIC, alkalinity, majorand trace cations, anions, organometals and volatile species of Hg and Se).

ARA

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Ref. Wallon

Ref. Bachimaña

Ref. Baños de Panticosa

name Code SIZE (ha)

Catchment (ha)

Perimeter (m)

Altitude (m)

Maximum depth (m)

Volume (m3)

Water renewal time

(month)Lac de la Badète BAD 7.0 79.9 2403.5 2341 7.0 243990 2.9

Lac de Pourtet POU 5.9 48.7 1458.4 2403 13.0 387705 7.5

Lac d'Aratille ARA 5.9 296.4 1065.1 2256 9.0 264307 0.8

Grand lac de Cambales CAM 3.5 179.7 1114.4 2344 12.0 208745 1.1

Lac Nere NER 2.9 94.8 745.1 2304 12.2 178522 1.8

Lac de Peyregnets de Cambalès PEY 1.2 15.2 467.9 2493 9.0 52987 3.3

Lac de Petite Opale OPA 0.6 129.3 308.7 2290 8.0 25788 0.1

Lac du Paradis PAR 0.4 25.4 292.7 1620 7.6 16570 0.6

Ibón de los Arnales ARN 2.6 93.5 710.0 2320 6.5 84579 0.8

Ibón de los Baños de Panticosa PAN 5.5 3229 970.5 1640 17.0 470072 0.1

Ibón Azul Superior AZU 3.9 151.4 1083.3 2420 14.0 273527 1.7

Ibón de Xuans XUA 3.0 41.3 936.0 2600 12.3 183875 4.2

Ibón de Coanga COA 0.6 27.9 332.9 2304 7.9 23208 0.7

Ibón de Ordicuso ORD 0.4 14.9 256.7 2100 7.5 14171 0.8

Ibón de Pecico Inferior PEC 1.2 64.6 439.8 2560 9.1 56724 0.8

Ibón de Bachimaña inferior BAC 3.2 - - 2181 - - -

Acknowledgements: This work has been partially supported (65%) by the FEDER funds through the INTERREG V-A Spain-France-Andorra (POCTEFA 2014-2020) (REPLIM project, ref. EFA056/15), and bythe Basque Government through the Consolidated Research Group Program 2013-2018 (Ref. IT-742-13). Bastien Duval is grateful to the Basque Government for his pre-doctoral fellowship.

SOME RESULTS

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Temperature, conductivity, pH, redox potential, dissolved oxygen, organic matter andchlorophyll were also measured in-situ by means of a multiparameter sonde. A profile ofthese parameters with depth was also recorded in some of the lakes.

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summer autumnFig. 1: Temperature profiles obtained in Arnales lake in summer andautumn, respectively. No presence of the thermocline was observed.

Fig. 2: Spatial distribution of Ba and As (in ng/g) within lakes. The season(summer/autumn) and the area (Cauterets/Panticosa) are indicated.Some trace elements presented systematic high concentrations in somelakes (e.g. Ba in Azul Superior lake). A strong dilution effect was alsoobserved for some trace elements (e.g. As) either in summer or inautumn, being the concentrations lower along the basin: Pecico > AzulSuperior > Bachimaña > Baños de Panticosa.