There are lots of slacker trees out there.

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Lucas
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There are lots of slacker trees out there.

Post by Lucas » Wed Aug 27, 2014 1:59 pm

http://www.sciencedaily.com/releases/20 ... 100855.htm

A new analysis suggests the planet can produce much more land-plant biomass -- the total material in leaves, stems, roots, fruits, grains and other terrestrial plant parts -- than previously thought.


The study, reported in Environmental Science and Technology, recalculates the theoretical limit of terrestrial plant productivity, and finds that it is much higher than many current estimates allow.

"When you try to estimate something over the whole planet, you have to make some simplifying assumptions," said University of Illinois plant biology professor Evan DeLucia, who led the new analysis. "And most previous research assumes that the maximum productivity you could get out of a landscape is what the natural ecosystem would have produced. But it turns out that in nature very few plants have evolved to maximize their growth rates."
DeLucia directs the Institute for Sustainability, Energy, and Environment at the U. of I. He also is an affiliate of the Energy Biosciences Institute, which funded the research through the Institute for Genomic Biology at Illinois.
Estimates derived from satellite images of vegetation and modeling suggest that about 54 gigatons of carbon is converted into terrestrial plant biomass each year, the researchers report.
"This value has remained stable for the past several decades, leading to the conclusion that it represents a planetary boundary -- an upper limit on global biomass production," the researchers wrote.
But these assumptions don't take into consideration human efforts to boost plant productivity through genetic manipulation, plant breeding and land management, DeLucia said. Such efforts have already yielded some extremely productive plants.

For example, in Illinois a hybrid grass, Miscanthus x giganteus, without fertilizer or irrigation produced 10 to 16 tons of above-ground biomass per acre, more than double the productivity of native prairie vegetation or corn. And genetically modified no-till corn is more than five times as productive -- in terms of total biomass generated per acre -- as restored prairie in Wisconsin.

Some non-native species also outcompete native species; this is what makes many of them invasive, DeLucia said. In Iceland, for example, an introduced species, the nootka lupine, produces four times as much biomass as the native boreal dwarf birch species it displaces. And in India bamboo plantations produce about 40 percent more biomass than dry, deciduous tropical forests.

Some of these plants would not be desirable additions to native or managed ecosystems, DeLucia said, but they represent the untapped potential productivity of plants in general.
"We're saying this is what's possible," he said.

The team used a model of light-use efficiency and the theoretical maximum efficiency with which plant canopies convert solar radiation to biomass to estimate the theoretical limit of net primary production (NPP) on a global scale. This newly calculated limit was "roughly two orders of magnitude higher than the productivity of most current managed or natural ecosystems," the authors wrote.

"We're not saying that this is even approachable, but the theory tells us that what is possible on the planet is much, much higher than what current estimates are," DeLucia said.
Taking into account global water limitations reduced this theoretical limit by more than 20 percent in all parts of the terrestrial landscape except the tropics, DeLucia said. "But even that water-limited NPP is many times higher than we see in our current agricultural systems."

DeLucia cautions that scientists and agronomists have a long way to go to boost plant productivity beyond current limits, and the new analysis does not suggest that shortages of food or other plant-based resources will cease to be a problem.
"I don't want to be the guy that says science is going to save the planet and we shouldn't worry about the environmental consequences of agriculture, we shouldn't worry about runaway population growth," he said. "All I'm saying is that we're underestimating the productive capacity of plants in managed ecosystems."
We travel the Milky way together, trees and men. - John Muir

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Don
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Re: There are lots of slacker trees out there.

Post by Don » Thu Aug 28, 2014 12:03 am

The answer lies not in how to more efficiently feed the growing masses, but in how to diminish the growing masses. We came into an Earth that was operating on a sustained yield basis...
Don Bertolette - President/Moderator, WNTS BBS
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Lucas
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Re: There are lots of slacker trees out there.

Post by Lucas » Thu Apr 16, 2015 1:41 pm

http://www.sciencedaily.com/releases/20 ... 083355.htm

The ongoing effort to turn trees into corn.
We travel the Milky way together, trees and men. - John Muir

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Don
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Re: There are lots of slacker trees out there.

Post by Don » Thu Apr 16, 2015 2:36 pm

Lucas
Recent threads on New Zealand redwoods growing to over 200 feet in 100 years approach such 'optimization' but at the cost of wood strength and character, such as is found in old-growth redwoods of northern California. There it's been determined that the once thought over-mature redwoods are producing far more incremental volume than they were thought to.
Old-growth redwood, as a lumber product and as curly-grain paneling has far more value-added potential than 'optimized' young second-growth redwoods. Let's hear it for slackers!
-Don
Don Bertolette - President/Moderator, WNTS BBS
Restoration Forester (Retired)
Science Center
Grand Canyon National Park

BJCP Apprentice Beer Judge

View my Alaska Big Tree List Webpage at:
http://www.akbigtreelist.org

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Rand
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Re: There are lots of slacker trees out there.

Post by Rand » Thu Apr 16, 2015 4:45 pm

For example, in Illinois a hybrid grass, Miscanthus x giganteus, without fertilizer or irrigation produced 10 to 16 tons of above-ground biomass per acre, more than double the productivity of native prairie vegetation or corn. And genetically modified no-till corn is more than five times as productive -- in terms of total biomass generated per acre -- as restored prairie in Wisconsin.
I really have to wonder what the plant, and perhaps the ecosystem at large, sacrifices over the long term to do this. The universe has a nasty habit of enforcing 'You can't get something for nothing' in surprising ways.

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Erik Danielsen
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Re: There are lots of slacker trees out there.

Post by Erik Danielsen » Thu Apr 16, 2015 9:50 pm

Absolutely. It's somehow become crazy to suggest that instead of getting trees and other plants to grow bigger, faster, we humans might benefit from doing things smaller, slower. It's not even that we have that much to lose by moving in such a direction, in the end; there are more efficient ways to do pretty much all of the things we rely on big, "fast" mechanisms to do. But hey. There's a lot of money in the status quo.

Joe

Re: There are lots of slacker trees out there.

Post by Joe » Fri Apr 17, 2015 8:10 am

I'm just wondering what that author's unspoken mission might be. He, "directs the Institute for Sustainability, Energy, and Environment"- so he may be pitching biomass for energy.

The idea of growing more biomass isn't necessarily a wise objective- it's the quality of the biomass for food and fiber that should be the primary goal- but producing some biomass for energy as a byproduct of high quality food and fiber is a reasonable secondary goal.

Here in Massachusetts, a few years ago we had the equivalent of WWIII over biomass for energy and the biomass energy businesses lost that war, along with the forestry people who could have benefited from a biomass industry.

Biomass for energy, of course, results in carbon emissions- but the jury is still out over whether this is really a bad thing because well managed landscapes producing biomass will sequester more carbon- so at least that carbon is already in the carbon cycle- unlike fossil fuel carbon.

Perhaps the best way to produce more biomass is to reduce the population but I don't see that happening without a major war or plague. But at least we should stop paving over the landscape for more shopping centers and housing developments. Instead, we should rip up the ugly, failed urban areas and rebuild those. It's not just old growth forests that should be protected- all undeveloped land should be protected from the bulldozers.
Joe

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