Quaternary enviromental evolution of the Argentinean Pampa Deprimida based on molluks and ostracod análysis

PISANO, F; CUSMINSKY, G; FUCKS, E

LETHAIA

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2023 vol. 56 p. 1 - 20

0024-1164

Multiproxy analyses are efficient approaches in palaeoenvironmental reconstructionssince they contemplate the different responses of various taxonomic groups to externalchanges. In this study, we analyse changes in molluscs and ostracod palaeocommunitiesto reconstruct the environments and their Holocene evolution in the SaladoRiver, Pampa Deprimida of Argentina. We assessed the temporal and spatial variationof the assemblages from the Alberti-Pla, Ruta 30, and Vientos de Mar localities throughvarious analytical techniques, including analysis of similarity (ANOSIM) and ordinationmethods such as non-metric multidimensional scaling (NMDS), detrended correspondenceanalysis (DCA), and principal component analysis (PCA). Eleven species ofgastropods were identified, among which Heleobia parchappii, Biomphalaria peregrina,and Succinea meridionalis stand out for their abundance. Nine species of ostracods wererecognised, with Limnocythere cusminskyae, Cypridopsis vidua, Heterocypris similis, andCyprideis salebrosa being the most important. The changes in the assemblages allowedus to infer the paleoenvironmental evolution in the area. During the Late Pleistoceneand Early Holocene, drier conditions led to ephemeral, marshy freshwater environmentswith fluctuating water levels and salinities. In the Late Holocene, increased precipitationcaused water levels to rise, resulting in more stable and interconnected freshwater environments.□ Holocene, Argentine Pampas, calcareous microfossils, continental palaeoenvironments,multiproxy analyses.