Mosses thrive in some of the most extreme environments. Take, Syntrichia caninervis, a small desert moss found around the world from the Great Basin in the western United States to the Gobi Desert in China. Getting water is no easy task in these arid environments, but this moss’ efficient water collection system has those that discovered it in awe.
Tadd Truscott, an assistant professor at Utah State University and co-author on the research recently published in Nature Plants described how the plant uptakes water using thin hair-like projections or “awns” that extend from the tip of each leaf.
“A typical plant will use its roots to gather water. What is different for the moss is that it doesn’t use its roots, but it uses these hairs. Each of the leaves has a single awn at the tip. They are narrower at their tip than they are at their base, and this is part of the reason why water droplets are able to travel from the tip to the tail. When the water gets to the [leaf], the leaf will mechanically open up and start to photosynthesize very rapidly,” said Truscott.
Each awn is decorated with grooves and barbs, which aid in water condensation and collection as well as droplet formation. These structures allow the moss to capture any available water source- raindrops, fog, even water vapor- and transport it to the leaves. In fact, Syntrichia may be thriving in an environment where other plants are struggling to survive.
“One thing you can infer from the study is that these plants drink maybe every day, every other day, or even every third day; whereas, their counterparts might not get water except every 10-20 days when there is a small rainstorm,” Truscott said.
These awns are providing inspiration for several engineering applications ranging from construction of fog and dew collection systems to improved urinal design. Better urinals? Truscott thinks so.
“[The awns] are compliant. They move when a rain droplet impacts them, damping out some of the energy," he said. "In our lab, we have looked at urinals for a long time. We’ve studied the idea of multiple droplets impacting on things and how to reduce splashback. It’s a little embarrassing, but it’s a ubiquitous problem. If you add this component of flexibility [to urinals] that [could] change things a lot."
We’ll have to wait and see what the future holds for urinals. In any case, this desert moss has an impressive water collection system, which is driving insights into engineering applications and the unique adaptations organisms have to survive in extreme environments.
Video (Credit Tadd Truscott):
https://www.youtube.com/watch?v=Akx0_0QiyFo
Additional Information: This work was a collaboration between Brigham Young University, Xinjiang Institute of Ecology and Geography of the Chinese Academy of Sciences, and Utah State University.
Journal Reference: Zhao Pan, William G. Pitt, Yuanming Zhang, Nan Wu, Ye Tao, Tadd T. Truscott. The upside-down water collection system of Syntrichia caninervis. Nature Plants, 2016; 2 (7): 16076 DOI: 10.1038/nplants.2016.76
