Smooth horsetail plants: Nature’s Water Distillers
Smooth horsetail plants have segmented stems
piemags/nature/Alamy
A fascinating plant species, known as horsetails, has the remarkable ability to distill water to an extreme degree, resulting in water that closely resembles that found in meteorites rather than typical Earth water. These plants, which have been present on Earth since the time animals first inhabited land, play a crucial role in contemporary ecosystems and offer valuable insights into the climate and water systems of ancient eras, including the time of dinosaurs.
The composition of water, particularly the ratio of oxygen isotopes, can provide valuable information about the history and source of a water sample. By studying these isotopic ratios, scientists can determine various factors such as the origin of the water, the rate of water movement through a plant, and the environmental conditions experienced by the plant in the past.
One of the challenges in studying these isotopic ratios is the presence of heavier isotopes in small quantities, making data collection and analysis complex. Researchers, led by Zachary Sharp from the University of New Mexico, encountered discrepancies in their data from desert plants and animals that could not be explained by existing models based on laboratory readings.
Through their study of unique horsetail plants with hollow, segmented stems, Sharp and his team were able to unravel this mystery. Horsetails, with their intricate structure, act as natural water distillers, with water undergoing multiple distillation processes as it moves through the plant’s segments.
By analyzing water samples taken from smooth horsetails growing in New Mexico, the researchers discovered that the isotopic ratio of water at the top of the plant was unlike any other water found on Earth, bearing resemblance to meteoritic water. This insight allowed them to refine their models and better understand the changes in isotopic ratios under ideal conditions.
These findings not only clarified the discrepancies in their desert plant data but also opened up possibilities for further exploration, especially in arid environments. Ancient horsetails, much taller than their modern counterparts and dating back millions of years, hold the potential to provide even more extreme isotopic ratios, offering valuable insights into ancient water systems and climates.
The presence of phytoliths in horsetail stems, which retain distinct isotopic signatures based on humidity levels, enables researchers to use these plants as “palaeo-hygrometers” for understanding past environmental conditions. This innovative approach showcases the significance of horsetail plants in unlocking the mysteries of Earth’s water systems and climate history.
Topics:
