Scientists recently discovered that a certain plant, Helianthemum squamatum, is able to extract up to 90% of its fluid requirements from crystallization water trapped in gypsum rock. It is currently the only known plant species able to do this and the finding represents a completely new kind of water source for life. The research was published on August 18 in Nature Communications.
The team of researchers, led by plant biologists Dr. Sara Palacio of the Instituto Pirenaico de Ecología in Spain and Dr. Juan Pedro Ferrio of the University of Lleida, exploited the different isotopic compositions of hydrogen and oxygen between gypsum water and free soil water. By examining the isotopic composition of the sap water of H. squamatum, the researchers could then infer what proportion of gypsum crystallization water contributes to plant survival. The top 10 centimeters of the soil was sampled for free soil water.
The researchers found that in summertime, 70% to 90% of the sap water resembled the composition of gypsum cystallization water. The authors shot down hypotheses that the sap water obtained water from the soil and underwent isotopic changes to resemble gypsum crystallization water.
Gypsum an extremely soft mineral. It's found in arid regions in Africa, Western and Central Asia. Its role at sustaining life was hinted at as far back as the early 19th century, when it was considered a fertilizer and a source of sulfur for plant growth. According to Neomatica, approximately 20% of gypsum's weight is water, though this amount changes as the aridity of the environment changes. The high percentage of water by weight, and the fact that plants are often observed growing on top, has seriously suggested gypsum's larger role in sustaining life.
The researchers involved in the H. squamatum discovery suggest their findings may impact the field of astrobiology. Gypsum is plentiful on other planets. It is conceivable that if life exists on other planets without traditional sources of water, they could have evolved to use crystallized water in rock instead.