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Giant trees have no trouble pumping water to top branches: new research

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Re: Giant trees have no trouble pumping water to top branches: new research

#51

Post by Sharlin »

fc417fc802 wrote: post #45
nomel wrote: post #14

This goes against all previous research/measurements for actually tall trees (looks like they only considered up to 80m) and the fact that there are exactly zeros trees in the world taller than 130 meters [1]. Wide capillaries at the base, like stated in the article, don't seem to be related. [1] https://www.sfgate.com/science/article/REDWOODS-How-tall-can...

I agree it doesn't pass the sniff test (where are the 500 meter trees in the rainforests?) but I think it would make an excellent goal for molecularbiological and genetic engineering. We (our civilization) need to become much more skilled at that before we start editing the human germline, and we will inevitably want to edit the human germline eventually (or rather we are currently exhibiting great restraint in not d…

There are obviously other factors limiting tree growth, like compressive strength.

Re: Giant trees have no trouble pumping water to top branches: new research

#52

Post by theendisney »

tenuousemphasis wrote: post #26
pulvinar wrote: post #20

Earlier quoted context omitted.

The trick for trees is capillaries, which change the equation. The 10 meter limit only applies to larger columns. With capillaries there's a high negative tension that allows evaporation from leaves to pull the xylem sap up 100 meters or more. There's no free lunch here. The Sun drives the evaporation, and if the tree were in a closed system with no solar input, the humidity would eventually get high enough to stop i…

>if the tree were in a closed system with no solar input ... that would be the least of the tree's problems.

This line of reasoning has always cracked me up. The internal dialog acidentally out loud at the least flattering moment. I believe the correct response to be:

The tree is a perpetual motion machine hooked up directly to the wheelworks of nature! It PUMPS 500 liters per day usibg Wind, solar, capilar action and evaporation! How do i charge my car with this?

Re: Giant trees have no trouble pumping water to top branches: new research

#53

Post by Sharlin »

fc417fc802 wrote: post #46
chowells wrote: post #15

Earlier quoted context omitted.

If you think of it that way, you have a real problem. It only takes about 10 meters for the weight of a column of water to create enough downward force that it starts vaporizing, at which point no pumping action works. This is why any deep well has a submerged pump. You simply can't pull water upward further than that with negative pressure in the Earth's atmosphere. It must be pushed with positive pressure instead.…

That analysis only applies to a single discreet pump. A line of pumps in series does not suffer from that problem and that is roughly what a biological system would be expected to consist of.

There are no pumps in a tree, in series or not. There’s nothing between the roots and leaves that actively drives water upward in any way. The xylem is literally dead tissue.

Re: Giant trees have no trouble pumping water to top branches: new research

#54

Post by fc417fc802 »

rolph wrote: post #24
rolph wrote: post #11

Earlier quoted context omitted.

more like capillary action. https://en.wikipedia.org/wiki/Xylem#Cohesion-tension_theory

the research is relevant to the issue of transpiration column hieght as a postulated limitation to overall hieght of any tree. a column of water is pulled by hydrogen bonding between molecules in a tug of war fashion, the top of the column is where water is dissociated from the column at such a rate as to maintain low pressure with respect to the column[xylem] in summary water moves from bottom to top in a transpirat…

> a transpiration stream, that ultimately ejects water vapour from the leaves

I don't believe this is correct, or rather is not a required component of the system but rather incidental. The chemical system within the leaf removes water via chemical reaction. There is a respiration process to dispose of waste gasses. Water vapor happens to be lost to this process not of necessity but rather because keeping it separate is quite difficult (ie requires significant complexity and additional energy expenditure). I expect that many desert adapted species approach perfection (but have not bothered to verify).

Re: Giant trees have no trouble pumping water to top branches: new research

#55

Post by theendisney »

kijin wrote: post #39
c22 wrote: post #34

Earlier quoted context omitted.

Kind of like how the vast majority of weight loss in animals happens via exhaling. Weirder still is the realization that all the air is just trapped light.

Actually, all matter is just trapped energy.

There is no such thing as energy.

Re: Giant trees have no trouble pumping water to top branches: new research

#56

Post by theendisney »

pkghost wrote: post #40

Folks still sleeping on structured water. While admittedly contested and only reproduced by a few labs outside Gerald Pollack's at University of Washington, there is a solid case that it could play a role in transporting water and sap to the tops of trees. At least, it's involved in the motion induced in hydrophilic tubes when there is sufficient ambient radiant energy (uv/infrared). Relevant papers: "Exclusion-zone…

I regretably didnt save it but there was a truly hilarious topic on usenet sci.physics long long ago. If we've gathered enough evidence against something or if the thing goes against accepted consensus you are forbidden from doing further research and new evidence is no longer allowed. The topic then invited others to list such topics. The list grew to hundreds of entries and people couldnt resist getting angry reading their personal trigger words despite there being many more silly things on it.

Yours shall be filed under homeopathy :)

Re: Giant trees have no trouble pumping water to top branches: new research

#57

Post by cortesoft »

nomel wrote: post #14

This goes against all previous research/measurements for actually tall trees (looks like they only considered up to 80m) and the fact that there are exactly zeros trees in the world taller than 130 meters [1]. Wide capillaries at the base, like stated in the article, don't seem to be related. [1] https://www.sfgate.com/science/article/REDWOODS-How-tall-can...

Couldn't both things be true? Water transport is not the limiting factor, but some other thing is?

Re: Giant trees have no trouble pumping water to top branches: new research

#59

Post by gre »

fc417fc802 wrote: post #45
nomel wrote: post #14

This goes against all previous research/measurements for actually tall trees (looks like they only considered up to 80m) and the fact that there are exactly zeros trees in the world taller than 130 meters [1]. Wide capillaries at the base, like stated in the article, don't seem to be related. [1] https://www.sfgate.com/science/article/REDWOODS-How-tall-can...

I agree it doesn't pass the sniff test (where are the 500 meter trees in the rainforests?) but I think it would make an excellent goal for molecularbiological and genetic engineering. We (our civilization) need to become much more skilled at that before we start editing the human germline, and we will inevitably want to edit the human germline eventually (or rather we are currently exhibiting great restraint in not d…

> 500m

500ft is taller than the max ever, not 1640 ft

Re: Giant trees have no trouble pumping water to top branches: new research

#60

Post by karim79 »

I grow marijuana and chillies from time to time. I got good at it. I will say that plants are malleable in untold ways and so I find this article to be unsurprising.

Plants will do what they need to do in the end. I've done stuff like co2 bombing, and increasing nutrients to the point to where I get a whole new ecosystem of insects and an entirely new situation.

It is such fascinating stuff that it's actually the life I want to live. I'm a computer scientist but now I yearn for the botanical sciences.

I highly recommend checking out defoliation strategies and low-stress training methods for anyone interested. Plants are not dumb creatures. The results you can get from them are astonishing and the science of what plants actually are becomes more profound by the day.

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