Assessing links between late Holocene climate change and paleolimnological development of Pena Lagoon using opal phytoliths, physical, and geochemical proxies

作者：del Puerto, Laura; Bracco, Roberto; Inda, Hugo; Gutierrez, Ofelia; Panario, Daniel; Garcia-Rodriguez, Felipe

来源：Quaternary International, 2013, 287: 89-100.

DOI：10.1016/j.quaint.2011.11.026

• LATE PLEISTOCENE
• SOUTH-AMERICA
• TROPHIC STATE
• ROCHA LAGOON
• SEA
• GRASSLAND
• ARGENTINA
• DYNAMICS
• PLAINS
• PALEOSALINITY

Opal phytolith, geochemical and sedimentological data from two cores taken in Pena Lagoon, a small water body on the Atlantic shore of Uruguay, are presented in this paper. The choice of this specific sampling location aimed to obtain high resolution records to infer late Holocene environmental and climatic changes in southeastern Uruguay, in order to improve previous models for early and middle Holocene. The combined record of two cores extends to 2500 C-14 BP, with a sedimentation rate ranging between 0.6 and 2 mm y(-1). A multiproxy approach allowed the identification of changes in dynamics, particularly organic matter and sediment input variability from the watershed. With this information, differences in the amount and extent of environmental signals were evaluated and a comprehensive climate change model was generated, especially for the last 1500 years. Three main climatic events were distinguished. The oldest, which lasted until 700 AD, was characterized by temperate and humid conditions. The second extended until 1200 AD and warmer and wetter conditions were inferred, but also a colder and drier pulse was observed in between. This second event was assigned to the Warm Medieval Period (WMP). During the third event, assigned to the Little Ice Age (LIA), which extended until the present, a high variability in climate was observed, but also three dry/cold phases reaching their maxima by 1300, 1600 and 1900 AD were inferred.

• 出版日期2013-2-21