“Unlocking Nature’s Secrets: MSU Researcher Delves into the Mysteries of Earth’s Water Cycle”

BOZEMAN, Mont. — Researchers from Montana State University have developed the initial global approximations of water stored within plants and the duration for water to circulate through them.

The findings were released on January 9 in the journal Nature Water, led by Andrew Felton, an assistant professor in the MSU Department of Land Resources and Sciences.

In the research, Felton discovered that Earth’s vegetation holds 786 cubic kilometers of water, which is sufficient to fill Flathead Lake approximately 34 times.

The time taken for this water to return to the atmosphere varies from five days in agricultural areas to 18 days in coniferous forests.

Additionally, he found that the global mean duration for water to re-enter the atmosphere is 8.1 days, while the water contained in lakes is anticipated to take 17 years.

By amalgamating various metrics, Felton is capable of calculating the time required for a single drop of water to traverse the complete cycle.

Montana State University released the following announcement:

A novel study led by a researcher within the Montana State University College of Agriculture offers the first thorough global estimates of water stored in plants and the duration for that water to move through them. This research closes a gap in our comprehension of the global water cycle and its transformation due to land use and climate changes.

Andrew Felton, an assistant professor at MSU’s Department of Land Resources and Environmental Sciences, is the primary author of the study published on January 9 in the journal Nature Water. This publication represents the culmination of work Felton began during a postdoctoral stint at Chapman University in California.

Felton found that all vegetation on Earth accumulates around 786 cubic kilometers of water, approximately enough to fill Flathead Lake 34 times over. The duration for water to move through plants and return to the atmosphere—termed “transit” or “turnover” time—varies from five days in agricultural lands to 18 days in evergreen forests, according to the research.

Felton emphasized that these findings highlight the dynamic function of vegetation in the water cycle. Globally, the average time for water to transit through plants and back to the atmosphere is 8.1 days. In comparison, vegetation in lakes is estimated to require 17 years while the water in glaciers is projected to take 1,600 years.

“We have recognized that most of the water returning from the ground to the atmosphere does so via plants, but until now, we were not truly aware of how long this process took,” Felton stated. “Our data indicates that the movement of water through plants occurs within days, rather than months, years, or even centuries.”

By merging estimates of water transit through plants with atmospheric transit (approximately 8-10 days) and soil transit (around 60-90 days), scientists can begin to estimate the complete duration it takes for a drop of water to navigate through the entire terrestrial water cycle. They observed that the water transit time through vegetation significantly varies among different land cover types, climatic conditions, and seasons. The transit period in agricultural fields was consistently the quickest, with water passing through plants in less than a day during peak growing season.

“A significant observation is that agricultural lands globally often exhibit very similar and rapid transit times,” noted Gregory Goldsmith, another author of the study and an associate professor of biological sciences at Chapman University. “This suggests that changes in land use could be standardizing the global water cycle and contributing to its intensification by hastening the recycling of water back to the atmosphere, leading to heavy precipitation events.”

To produce these estimates, the research team initially calculated the volume of water contained in plants utilizing data from NASA’s Soil Moisture Active Passive satellite program, which provided high-resolution measurements of soil water content. The mission originally considered plants as obstructing soil moisture evaluation and adjusted for their presence, but Felton’s team identified that these adjustments concealed valuable data regarding the volume of water held in plants.

“Plants are the overlooked element of the global water cycle,” stated Felton. “The findings suggest that the transit duration of water through plants is likely to be significantly impacted by events such as deforestation, drought, and wildfires.”

Moreover, the research has local relevance for Montana, he added.