BGU team finds freshwater springs in Dead Sea

German group pinpoints new types of microorganisms growing in fissures on the saline seafloor near the springs, university announces.

By SHARON UDASIN
The Dead Sea Works 311 (photo credit: Ariel Jerozolimski)
The Dead Sea Works 311
(photo credit: Ariel Jerozolimski)
A Ben-Gurion University research team has discovered a series of deep freshwater springs that spring from the floor of the Dead Sea and help replenish the body’s dwindling water supply, while a German group has meanwhile pinpointed new types of microorganisms growing in fissures on the saline seafloor near the springs, the university announced on Wednesday.
The BGU team, led by Prof. Jonathan Laronne and research student Yaniv Munwes from the Department of Geography and Environmental Development, is funded by the Sustainable Management of Water Resources in the Dead Sea Area Project of 2008-2011 from the Federal Ministry of Education and Research of Germany.
Using professional divers in their research, the group was able sample the spring sources, understand flow structure and calculate spring discharge and morphology based on submarine photography, the university said in a statement.
Dead Sea groundwater springs have been known and visible for decades as they produce ripples on the water surface, but the current research has given scientists to the ability to study springs that are hidden from the eye, according to the statement.
Much like the Dead Sea itself, the springs have been around for thousands of years, and while it is “uncertain” whether they’ve existed quite as long as their host body of water, they have been there “for a very long time indeed,” Laronne told The Jerusalem Post.
The springs, he continued, can be found at locations within the sea as deep as 30 meters down, and the largest spring observed thus far was 15 meters in diameter – with some spring systems totaling hundreds of meters in length.
While the number of springs are not known, Laronne said that they are now known to be particularly prominent in certain areas, such as near Ein Fes- ’sha.
The water appears to jet out of the springs quite continuously, according to Laronne.
“We have observed the springs and it appears so, but we have not monitored them continuously,” he said. “Some of those we have observed have remained in place during two years of observation – so likely continuously.”
While his team has not yet determined how much water the springs are contributing to the Dead Sea each day, “the methodology to do so now exists,” Laronne added.
And although the amount of water contributed to the sea from the springs is not large in comparison to the amounts siphoned off for a multitude of uses in Israel, Jordan and the Palestinian Authority, it is a sizable contribution nonetheless, according to Laronne.
“It is not [significant] relative to the amounts that have been taken from upstream [the Jordan River] and to the evaporation ponds; however, these are very considerable rates that will help to establish the water budget of this most-deep sea on earth,” he said.
In a separate, concurrent study, the second team to announce its Dead Sea findings on Wednesday – of newly discovered microorganisms paving the seafloor near these same springs – is led by Hebrew University graduate Dr. Danny Ionescu of the Microcensor Group at the Max Planck Institute for Marine Microbiology in Bremen, Germany, the BGU statement said.
Some of the microorganisms discovered by Ionescu’s group have never before been found to survive in such highly saline environments, according to the statement. Most belong to the domain Archaea and number around 1,000-10,000 per milliliter – a much lower concentration than found in regular sea water, Ionescu explained in the same report. The team plans to follow up on its research with a trip to the Dead Sea next month.
“Never before have microbial mats/biofilms been found in the Dead Sea and not much is known about sediment microorganisms in the Dead Sea,” Ionescu said in the statement.
“The biofilms we found contain phototrophs and sulfide oxidizers and many other species – most of the findings rely on molecular analysis – and our next expedition in October will deal with the actual activity of these organisms and the many more questions that arose from these findings.”