Escalating Thirst

Endangered Western Tree Habitats




A team of scientists at the University of Grenoble, in France, have isolated ultrasonic pops 100 times faster than what a human can hear in slivers of dead pine wood bathed in a hydrogel to simulate the conditions of a living tree. They exposed the gel to an artificially dry environment and listened for the noises that occurred as air bubbles built up, blocking water uptake, similar to what occurs to trees during drought. As leaves on a tree collect carbon dioxide, they open their pores, a process that leaves them particularly vulnerable to water loss.

Douglas firs and pine trees can repair this damage as frequently as every hour, says Katherine McCulloh, a plant ecophysiologist at Oregon State University. However, the bubbles are deadly for other species.

Today, the typical forest in the often thirsty American West contains an unnaturally high density of 112 to 172 trees per acre. Besides intercepting rain and snow that would otherwise enter the groundwater supply, such an overabundance threatens native species. “Deprived of [the effect of] low-intensity, naturally occurring fires, aspen, lupine, sequoia and fireweed can’t reproduce,” notes Jamie Workman, of the Environmental Defense Fund. “Deer lose edge habitat. Threatened owls and raptors can’t navigate through increasingly dense thickets.” Workman argues that thinning out small trees is the answer.


Contributing source: Utne.com

Edit ModuleShow Tags

More from Natural Awakenings

Migrating Trees

Three-quarters of American tree species have shifted to the West since 1980 due to dryer conditions in the East and changing rainfall patterns.

Plutonium Problem

To safely dispose of 56 million gallons of nuclear waste dating back to the Second World War, the Department of Energy might replace a glass-log encasement plan with a cement option.

Bat Banter

Computer algorithms helped Israeli researchers decode the language of Egyptian fruit bats and discover that bats exchange information about specific problems.

Tuna Turnaround

Levels of toxic mercury in Atlantic Bluefin tuna declined 19 percent between 2004 and 2012, a drop that scientists attribute to a shift from coal to natural gas and renewable energy.

Buzzing RoboBees

Harvard researchers have invented tiny robotic bees that may be able to eventually pollinate the crops that are under threat because of vanishing bee colonies.
Edit ModuleShow Tags
Edit ModuleShow Tags