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Cheatgrass will migrate with climate change


Climate change will help some of the West's most troublesome invasive plants conquer new territory, but the pesky invaders will also retreat from some currently infested areas.

A new study published in the journal Global Change Biology predicts that yellow starthistle, an unpalatable rangeland invader established in much of California, will march across even more of the state and Nevada.

Cheatgrass, a highly flammable annual grass from Eurasia that blankets much of the Great Basin, will probably spread north into more of Idaho and parts of Montana and Wyoming but retreat from central and southern Nevada and central Utah.

Princeton University researchers examined 10 climate models and arrived at a "best guess" of how changes in such factors as seasonal and annual precipitation over the next century could affect the distribution of five prominent invasive plants.

Tamarisk, a shrubby tree that grows along streams and sucks up water, will probably be unaffected by climate change. Leafy spurge, abundant in northern states west of the Mississippi, will probably retreat in Colorado and parts of Idaho and Oregon.

Spotted knapweed, which grows in the foothills of the Rocky Mountains and on the Colorado Plateau, is expected to move to higher elevations.

"We're not talking about a wholesale retreat of invasives," said the study's lead author, biogeographer Bethany Bradley.

Instead, it will be more of a rearrangement of the invaders, providing some chances for ecological restoration.

But a changing climate will also affect native plants. Even if invasives die out, the researchers said, native growth that historically occupied an area may not be able to reestablish itself. Instead, other types of native plants suited to the new climate may move in. Or other invaders may take hold. For example, red brome, an exotic found in the Mojave Desert, could take over former cheatgrass lands.

— Bettina Boxall

Photo: Cheatgrass near Boise, Idaho. Credit: Brian Vander Brug / Los Angeles Times

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invasive species will get much, much worse once Big Energy is allowed to greenwash Big Solar, Big Wind and big Transmission, and destroys tens of millions of acres of intact ecosystem by dynamiting, bulldozing, scraping, blading new roads, etc. Nobody ever mentions the devastation these projects cause, they just cheer because they want to pretend they are "green." you know what's green? solar panels on your roof. all this dead wilderness is a ticking time bomb. why would so-called environmentalists prefer to destroy wilderness than to promote ratepayer generation? follow the money...

According to the IPCC, we've been warming at about 0.2 C/decade for the last couple of decades:

'Leemans and Eickhout 2004 found that adaptive capacity decreases rapidly with an increasing rate of climate change. Their study finds that five percent of all ecosystems cannot adapt more quickly than 0.1 C per decade over time. Forests will be among the ecosystems to experience problems first because their ability to migrate to stay within the climate zone they are adapted to is limited. If the rate is 0.3 C per decade, 15 percent of ecosystems will not be able to adapt. If the rate should exceed 0.4 C per decade, all ecosystems will be quickly destroyed, opportunistic species will dominate, and the breakdown of biological material will lead to even greater emissions of CO2. This will in turn increase the rate of warming' --Leemans and Eickhout 2004, 'Another reason for concern: regional and global impacts on ecosystems for different levels of climate change,' Global Environmental Change 14, 219–228

Here is what Climate Code Red says:

--Human emissions have so far produced a global average temperature increase of 0.8 degree C.

--There is another 0.6 degree C. to come due to "thermal inertia", or lags in the system, taking the total long-term global warming induced by human emissions so far to 1.4 degree C.

--If human total emissions continue as they are to 2030 (and don't increase 60% as projected) this would likely add more than 0.4 degrees C. to the system in the next two decades, taking the long-term effect by 2030 to at least 1.7 degrees C. (A 0.3 degree C. increase is predicted for the period 2004-2014 alone by Smith, Cusack et al, 2007).

--Then add the 0.3 degree C. albedo flip effect from the now imminent loss of the Arctic sea ice, and the rise in the system by 2030 is at least 2 degree. C, assuming very optimistically that emissions don't increase at all above their present annual rate! When we consider the potential permafrost releases and the effect of carbon sinks losing capacity, we are on the road to a hellish future, not for what we will do, but WHAT WE HAVE ALREADY DONE.

In other words, it is predictably that in the next couple of decades, due to an increased rate of warming, natural ecosystems will be quickly destroyed, invasive species will dominate, and the resulting feedback loop will further speed the rate of warming.


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