A recent paper co-authored by George Washington University Assistant Professor of Biological Sciences Amy Zanne finds that those systems in plants around the globe are operating at the top of their safety threshold, making forest ecosystems vulnerable to increasing environmental stress.
In the current issue of the journal Nature, Dr. Zanne and lead authors from the University of Western Sydney in Australia and Ulm University in Germany, report that the hydraulic system trees depend on is a unique but unstable mechanism that is constantly challenged.
“Drought is a major force shaping our forests,” said Dr. Zanne, a faculty member within the Columbian College of Arts and Sciences. “Over the last century, drought has been responsible globally for numerous large-scale forest diebacks. To make effective predictions of how forest landscapes may change in the future, we need to first understand how plants work.”
The primary challenge plants face during drought is how to keep their plumbing working. Drought stress creates trapped gas emboli in the water system, which reduces the ability of plants to supply water to leaves for photosynthetic gas exchange and can ultimately result in desiccation and death.
“Vulnerability to embolism is one of the main factors determining drought effects on trees,” Dr. Zanne said. “However, plants vary dramatically in their resistance to drought-induced embolism, which has made predictions of how forests might be altered under future climates more difficult.”
While the research findings are alarming, plants do have a few other tricks up their sleeves. They may have some flexibility of changing their plumbing or new species of trees may replace species no longer capable of persisting in a given place.
An international team consisting of Dr. Zanne and 23 other plant scientists organized via the ARC-NZ Research Network for Vegetation Function at Macquarie University in Sydney, Australia, analyzed existing measures of plant hydraulic safety thresholds in forest species around the world.
The surprising result that the group discovered is that while plants vary greatly in their embolism resistance, they are sitting at similar safety thresholds across all forest types. The team found these thresholds are largely independent of mean annual precipitation.
The findings explain why drought-induced forest decline occurs in arid as well as wet forests, which had historically not been considered at risk.George Washington University
Latarsha Gatlin | Newswise Science News
Family tree for orchids explains their astonishing variability
04.09.2015 | University of Wisconsin-Madison
Gone with the wind: A new project focusses on atmospheric input of phosphorus into the Baltic Sea
04.09.2015 | Leibniz-Institut für Ostseeforschung Warnemünde
In a survey of NASA's Hubble Space Telescope images of 2,753 young, blue star clusters in the neighboring Andromeda galaxy (M31), astronomers have found that M31 and our own galaxy have a similar percentage of newborn stars based on mass.
By nailing down what percentage of stars have a particular mass within a cluster, or the Initial Mass Function (IMF), scientists can better interpret the light...
Researchers at the Fraunhofer Institute for Solar Energy Systems ISE have developed a highly compact and efficient inverter for use in uninterruptible power...
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from University of Arizona geoscientists. The study is the first to explain how the steep-fronted plateau formed.
China's Loess Plateau was formed by wind alternately depositing dust or removing dust over the last 2.6 million years, according to a new report from...
The leaves of the lotus flower, and other natural surfaces that repel water and dirt, have been the model for many types of engineered liquid-repelling surfaces. As slippery as these surfaces are, however, tiny water droplets still stick to them. Now, Penn State researchers have developed nano/micro-textured, highly slippery surfaces able to outperform these naturally inspired coatings, particularly when the water is a vapor or tiny droplets.
Enhancing the mobility of liquid droplets on rough surfaces could improve condensation heat transfer for power-plant heat exchangers, create more efficient...
Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.
"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...
03.09.2015 | Event News
20.08.2015 | Event News
20.08.2015 | Event News
04.09.2015 | Power and Electrical Engineering
04.09.2015 | Machine Engineering
04.09.2015 | Materials Sciences