Sediment Sample from Dead Sea Provide Insight into Climatic Past

Researchers from the University of Bonn’s Steinmann-Institute for Geology, Mineralogy and Paleontology in conjunction with Israel’s Geological Service and German Research Center for Geosciences have been able to deduce the climatic conditions of the Dead Sea over the last 10,000 years by studying the fossilized pollen present in soil samples obtained by drilling for 21 m in the west bank of the Dead Sea at the oasis Ein Gedi.

The age of the soil samples were determined by employing radiocarbon dating. The fossilized pollen was then matched with indicator plants to determine the conditions of temperature and precipitation required for the plants’ survival. The method enabled the researchers to map the climatic conditions of the postglacial period. The researchers found from their studies that the Dead Sea was home to three predominant types of vegetation. One was the thriving sclerophyll vegetation characteristic of moist conditions and similar to the vegetation around the Mediterranean Sea. The second was steppe vegetation under dry conditions. The third was desert vegetation when conditions turned even drier. The data from the analysis was validated by data on Dead Sea level fluctuations. The two data were found to correspond closely. The reason for moist phases corresponding to an increase in Dead Sea level and dry phases corresponding to fall in sea level is attributed to the fact that the Dead Sea water level is dependent on precipitation and evaporation owing to the absence of an outlet.

The results of the study are proof of vulnerability of the Dead Sea ecosystem and its tendency to turn into a desert at an alarming rate.

Source: http://www3.uni-bonn.de/