IDEAN   23403
INSTITUTO DE ESTUDIOS ANDINOS "DON PABLO GROEBER"
Unidad Ejecutora - UE
artículos
Título:
An ostracod-based calibration function for electrical conductivity reconstruction in lacustrine environments in Patagonia, Southern South America
Autor/es:
RAMON MERCAU, J; CECILIA LAPRIDA
Revista:
ECOLOGICAL INDICATORS
Editorial:
ELSEVIER SCIENCE BV
Referencias:
Lugar: Amsterdam; Año: 2016
ISSN:
1470-160X
Resumen:
In the Patagonian region (~37-56°S) E of the Andes, the salinity and solute composition of lakes is strongly related to their location along the marked W-E precipitation gradient that is one of the main climatic features of the area. A calibration function (n=35) based on ostracods (Ostracoda, Crustacea) was estimated by WA-PLS to quantitatively reconstruct electrical conductivity values as a salinity proxy. The selected model (r2= 0.74; RMSEP and maximum bias equal to 16% and 31% of the sampled range, respectively) was applied to the ostracod record of the closed lake Laguna Cháltel (49°58′S, 71°07′W), spanning the last 4600 years. In order to evaluate the calibration function?s robustness, the obtained electrical conductivity values were compared with qualitative lake level and salinity variations inferred for the lake for that period on the basis of a previously performed multiproxy hydrological reconstruction. Both reconstructions show good overall agreement, evidencing a tendency towards lake level increase and concurrent salinity decrease during the studied period, with some inconsistencies in parts of the record ascribed to significant time-averaging effects in one case and to the different weight attributed to salt crusts redissolution in the control of salinity in the other. This comparison not only lends support to the adequacy of the calibration function, but also suggests that its application in the context of a multiproxy study can greatly contribute to distinguish between autigenic and precipitation-related controls of paleosalinity in closed lakes, allowing performing more accurate paleoclimatic inferences on the basis of paleohydrological reconstructions