Juan I. Santisteban (Santi) is Lecturer at the Department of Stratigraphy of the Complutense University of Madrid (Spain) and Rosa Mediavilla is researcher at the Spanish Geological Survey (IGME). Both are sedimentologists and stratigraphers specialized in terrestrial deposits (fluvial and lacustrine) and interested in the integration of multiproxy data in the interpretation of terrestrial basins.
Most of their research has been carried in Cenozoic basins of inland Spain but during the last 15 years have been working in Quaternary wetland deposits in Spain. Nowadays, their focus of research is located in Las Tablas de Daimiel National Park, where they are part of the research team of the project “Palaleoclimatic and palaeohydrologic reconstruction of the Upper Guadiana (Tablas de Daimiel)”.
Las Tablas de Daimiel is a fluvial wetland very sensitive to climate or man induced perturbations. It is placed between the lowlands of Andalucia and the Spanish Meseta having been a natural border for most of its history.
Climate signal in this area has been controlled by water budget (rainfall, evapotranspiration). For the Holocene, pollen records show warmer temperatures than during the Pleistocene but arid phases are evident for ca. 5 ka BP, ca. 3 ka BP and ca. 1.5 ka BP. From this moment up to present, a better reconstruction of temperature and aridity allow us to show that temperature and rainfall evolve with similar periodicities but out of phase. Both the Medieval Warm Period, characterized by smooth oscillations of temperature and rainfall, and the Little Ice Age, characterized by abrupt oscillations in climate, have been identified.
All these changes affected the evolution of the wetland and the relation between it and people. People have been linked to its borders since Pleistocene times, when nomadic tribes (from Palaeolithic to Chalcolithic) wandered on its terraces looking for raw material. But it’s been since Bronze Age when population of the area has been almost constant. Since this moment, people´s activity has been related to the river/wetland as a supplier of water, raw material, energy or source of illnesses.
Three periods can be identified in this relation. A first stage, when people´s relation with water was ruled by climate and the activity of man caused no changes in the environment. A second stage, when people started to try to modify the hydrological system but without causing meaningful disturbances. And a third stage, when technological advances allowed people to cause irrecoverable changes in the wetland.
Date, Time: 14/07/2014, 17:45 h – 19:00 h
Location: Room S12, Seminargebäude (Building 106), Universitätsstraße 37 , Cologne