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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #561

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Dave:
You give the impression of not thinking that osmosis has any effect... and of doubting wheter it exists.

I think the abstract was coming up with a mechanism for how the Pholem can be at a positive pressure throughout it's length which is how the sugar can move through it with minimal use of energy.
employees.csbsju.edu/ssaupe/biol327/Lecture/phloem.htm

It is really neat - areas of the phloem with high sugar concentrations will draw in water from the xylem by osmosis so increasing their pressure. Areas which are using sugar have a low concentration of sugar and therefore a low osmotic pressure. Water flows away from regions of high pressure to the low pressure where the sugar is being used. This has the advantage of being able to move the sugar from where the sugar is being produced - either in the leaves most of the season, or from starch in the roots during the spring, to where it is needed.

I don't know whether I have acces to this article because I am in a university, but if you can I would defnitely read the introduction.
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #562

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Dear Doctor Saupe,

I wrote to you in April 2003 in order to explain a new paradigm in water movement in trees and plants. I never did get a reply and wonder if you would care to join our discussion at the Naked Scientist forum?

I believe your knowledge in this field would benefit this discussion immensely. I do understand that your commitments and demands on your time are high.
I hope you can find the time to look us up, as I believe we have a mutual interest in understanding the true functions of transpiration and water movement in trees.

Sincerely Andrew K Fletcher




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quote:You give the impression of not thinking that osmosis has any effect... and of doubting whether it exists.



Sorry for giving the wrong impression about osmosis. I believe that the accepted interpretation of osmosis is erroneous, as did Professor H.T.Hammel. Water cannot attract water to the leaves of a tree, any more than diffusion or root pressure can cause it to flow at the observed rates evident in trees! There has to be a method of loading an unloading sucrose as Stephen Saupe Suggests in his pages. The bulk flow rates observed in trees are undeniably massive and simply cannot be addressed by osmosis, capillary action, or root pressure! Saupe points to this problem in his pages. He also states that the phloem is under a positive pressure, demonstrated by aphids. This fits with my own experiment in the saline loaded side that does indeed flow down! He also states that there must be a sink. In my theory, I have mentioned the sink as being the roots and trunk for simplicity. There are also the fruits, leaves and minor branches that continue to grow providing additional sinks as Saupe also states.

Sauppe also states:
Bidirectionality - how can phloem translocate materials in two different directions at once? It can’t, at least not within the same sieve tube. However, presumably sieve tubes within a single vascular bundle could be transporting in opposite directions assuming each is acting appropriately.

The fact is that bi-directional flow in one tube is easily observed using my model, proving beyond any shadow of doubt that it will also occur inside a tree when the resistance in other pathways becomes congested!

I wrote to Stephen Saupe in Early January 2003, sending him information about my experiments. I never did get a reply.

XIII. Why does transpiration occur?
A. Transport in plants. This is important to a small degree. Transpiration is certainly not a necessity.
B. Heat loss (latent heat of vaporization)
C. Carry nutrients in the soil to the plant
D. Perhaps plant cells need to maintain some optimal level of turgidity and this helps them do so.

And lets not forget the picric acid and copper sulphate experiments killing all living cells in the tree and yet it still flows and transpires for three weeks post death of the tree.

I am surprised that he has failed to realise the importance of transpiration, density and gravity.

I have written to Stephen Saupe again to see if he will join us.

Andrew
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #563

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The probelm with osmosis is.....


arxiv.org/ftp/physics/papers/0305/0305011.pdf
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #564

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Dave:
Your link to a paper was not in any way arguing that osmosis is empirically wrong, or that the way that thermodynamacists explain osmosis or it's properties was wrong, just that the simplifications that are taught to school children are a bit dodgy - so it is still a real effect !!!

I don't see why the bulk flow rates are not possible by osmosis - the rate of osmosis may be slow per unit area - but there are a huge number of xylem and their surface area is huge - so it all adds up to a big number - unless you can do some maths to back up your argument it isn't very strong...

You didn't get my point about the Phloem - if it is all at an absolute positive pressure, if you wired one into the Xylem, theere would be flow of sugars into the xylem as the pressure is bigger there - THE WRONG WAY - so if this is the case your theory can't use the Phloem as the downward path (especially as sugars flow up or down a tree depending on the season....) - and I don't think there is anything else to use


Not at all David, if you wired a positive force generated by falling sap it would find the most direct route to the ground. The flow works totally independent to pressures! You can pressurise a tube to a hundred bar and this flow would still travel down inside the pressurised tube. It does not require any pressure to function; it generates pressures as it functions!


When I did the exhibition in London, I used a saline drip feed to enable many people to see the experiment, which was repeated well over a hundred times.

To do this I needed to set up an artificial bladder, which was on a T junction as you suggest, but at the bottom end of the tubes, to act as a sump for the saline pulses which eventually reached the lowest point. This worked remarkably well, enabling the pulses of saline solution to replace the clean water in 2x connected bladder wash bags, representing the kidneys on either side of a Catheter bag which had a convenient drain tap right at the bottom acting as the ultimate sump, and representing the bladder in human physiology which of course enabled us to empty it. This worked perfectly except for the formation of gas bubbles in the upward flowing side.

Some very large bubbles collected at the upper part of the somewhat complicated tubes, which looked a little like a tubular maze. The interesting thing with the bubbles is that the flow continued around the outside of the bubbles and it did not stop the flow.

Another interesting observation for people at the exhibition was that if the drip bag was allowed to flow a little more profusely, the large bubbles at the top of the experiment began to travel down with the saline flow, some of these bubbles measured 10 millimetres long in a 4 mill bore soft walled tube. One other point was that the bladder bag on the saline free side of the nighttime catheter bag emptied as the negative pressure caused by the downward flow pulled clean water into the system. Now the thing about this experiment is it was a closed loop system, and that the saline flow had to be the principle cause of the negative pressures and positive pressures generated. Pressure from the drip feed did not make any difference because there was a convenient method of isolating it.

But the gist of this reply is, that gravity will drive this circulation, and your T junction will not alter its course, because it is not pressure dependent, and is not trying to overcome gravity as with the embraced cohesion theory. This flow system actually requires gravity and therefore negates your previous energy equation, which after all still relates to gravity as being a force to overcome.
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #565

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Dave:
Regardless of what Chris may say about your bladder theories, you didn't understand what I meant:

The Phloem is at a positive pressure - this means that even at the top of the tree the phloem has a pressure greater than atmospheric.

We have established that the top of the xylem must have a negative absolute pressure of several atmospheres.

The reason your syphon works is that because the saline is more dense than pure water it pulls down slightly harder than the water side, so the pressure at the top on the downward side is a few mBar lower than at the top on the upward side, so water flows towards the upward side.

Now in a tree you have a Phloem at a pressure greater than an atmosphere and the xylem at a pressure of minus up to 10 atmospheres - there is no way you can make water flow into the xylem if they were attached to one another. you can't get water to flow against a 10 atmophere pressure difference without something else going on as it is a fluid and fluids flow from high pressure to low pressure... (if they are at the same height - which they are)

You can make osmosis produce this sort of pressure difference, but unless you are injecting mercury into the phloem, not how you are suggesting.
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #566

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Anthony:
Andrew, thanks for your reply, given your enthusiasm I would have been surprised if you hadn't already tried to publish. First of all, being published means lots of hard work, lots of time and inveitably rejections. Some of what is published shouldn't be and some of what should, isn't, editors try and do the best they can, the main advantage for the editors is that they always have much more than they can publish. The editors' main concern, with good reason, is the reputation of their journal, and the best way to loose that reputation is to publish bad science.

By extension, if I'm not surprised you've tried to publish, given the fact you haven't published, I suppose I am also not surprised you haven't. People in the arts have the same arrogance of people in the science. We think ours is the discipline that concentrates on logic, they think theirs is the one which concentrates on communication. I've found much of what you said very difficult to follow and given the fact that this argument has now reached about 40,000 words, the length of a short PhD thesis, it doesn't get any easier. So now you see why I made my offer. People say scientists speak a different language, I'm offering my services, and that of this forum, as translator.

All but one of the publications in which you have so far tried to publish are wholely inappriopriate for this work. New Phytologist was a good start, and I refer you to the list which I first posted. But you simply MUST read and understand what other people in the field have done first. Furthermore, you must not see it as potential plagarism. The sad truth is that ideas are very rarely new, and I'm sure your ideas are no different. What counts is working the idea, with a little proof, into something that someone else can have an idea with. That counts for you and me as much as it did for Einstein.

Science is now conducted by professional scientists, it's the 21st century. The time of the "Gentleman Scientist" is behind us, it's a concept I have some affection for, but will never be re-instated. The era of the Gentleman Scientist was one full of great cataloguers and makers of lists and trees in biology, geology and paleontology. Great observers who could see the connections between things. The physicists were developing the basis of modern science in laboritories, and by the end of Rutherford's time it was essentialy dead. Rutherford had PhD students and worked in a university after-all. Take no offence at this, but you are essentially a "living fossil." As such, you can be poorly adapted for the world at large.

As the abstract I posted shows, water transport in trees is very much the territory of the modern scientist. Modern science is built on layers of concepts each the foundatation for the next, that's why it takes six to eight years, undergraduate/PhD, to produce one modern scientist. Increasingly scientists have to draw on knowledge from different fields to progress. The abstract I posted for example, drawing on advanced thermodynamics, mathematics and computing to solve a simple biology problem. It is not easy, it is very, very difficult.

Everyone in this forum is trying to help but you are at a considerable evolutionary disadvantage. It remains possible for the Gentleman Scientist to publish, but you simply must research others work and communicate in the right way. It's our rules now. Alternatively you can withdraw from competition, which is ultimately the safer thing to do.

I remain true to my original offer, and make a second. If you are minded to look into other people's publications in the area, I will give you a list of journal articles that may get you started.
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #567

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Anthony

Thanks for your reply

I have taken much of what you have said on the chin. Your defence of editors and Journals in an ideal world would be acceptable. I have a huge amount of correspondences from these and many more journals, which I intend to publish for all to see, so that everyone can make up their own minds about why these people have the audacity to place such controls on science. But there is a huge swing right now towards a different kind of journal, and this has revived my spirit somewhat. Whenever there is a new discovery in Science of significant importance, History tells us that it is seldom the establishments that deliver it. In fact it is usually the “fossils” that provide us with solid foundations.

I am surprised that you suspect I have not read other peoples papers. I have! I also have a great deal of respect for Professor H.T.Hammel, Professor Michel Cabanac, Pete Scholander, Galileo, Evangelista Torricelli, Eduard Strasburger, Is there really any point in regurgitating old papers, which will place demands upon the permitted space in our publication. Other than a briefer mention than those set out in the links provided below? I do realise that other theory’s have to be shown to be weaker than this one, but how much time, effort and space has to be devoted to this?

For an excellent history of the ascent of sap, read the following.
www.plantphys.net/article.php?ch=4&id=98


www.plantphys.net/article.php?ch=4&id=99
A recent synthesis of the main features of the CTT and the electrical analogy used for modeling water transport in the soil-plant-atmosphere continuum has led to a new approach to plant and tree water relations: the hydraulic architecture approach. This approach considers a plant, and especially a tree, as a hydraulic system. All hydraulic systems (dams, irrigation systems for crops or houses, the human blood vascular system) are composed of the same basic elements: a driving force, pipes, reservoirs and regulating systems. So described, the hydraulic architecture is a powerful tool to study the hydraulic characteristics of the conducting tissues under a whole range of natural conditions. Important questions subject to study with the hydraulic architecture approach include:


I repeat: Anyone that has ever witnessed these simple experiments looks in awe and instantaneously accepts that this is exactly how trees lift water at bulk flow rates.
Anthony, I have to ask you to repeat at least the scaled down versions of these experiments, in order that it will clarify the text to the point that you will totally understand what it is we are dealing with here. A trip to the local aquarium retailer will provide you with the required tubes, junctions and T junctions, used to aerate fish tanks. While you may believe that you understand how this flow works at the moment, it is only when you see it work that the full implications of this discovery hits home.

You are sure that my theory is no different to what has been done before? Have you seen another?

How can you say this when every single paper has been trying to understand how everything living is struggling against gravity and trying to overcome gravity?
My theory embraces gravity as the power source that drives the fluids of all things living, As far as I know, no one has a theory that identifies how gravity causes water to flow vertically and effortlessly.

Science is now conducted by professional scientists, it's the 21st century. The time of the "Gentleman Scientist" is behind us, it's a concept I have some affection for, but will never be re-instated.


There is more than one way this statement can be interpreted. I believe that the professionalism of scientists has compromised science causing a considerable degree of stagnation in pure science. Everyone either is accepting what they read as fact or too afraid of rocking the boats for fear of being ostracised.

I believe you are quite wrong about this bubble of the closed shop being impregnable to outsiders. I believe someone may just come along with a pin and pop it, kicking science so far off its pedestal that a new breed of scientists will again emerge and science will again grow in leaps and bounds. I first heard this from a doctor on an Open University Programme who sated that Science is on a pedestal and that it is all B*******. Another scientist added that once it has been kicked off its pedestal, he hopes it will not fall so far as to become irreparably damaged, meaning I take it as losing all of its credibility. I think the programme was "The trouble with science"

Truth has an uncanny knack of turning round and biting us all in the butt, so telling it as it is, rather than as it isn’t sounds like a good standpoint.

I am not scared of a fight, and I can assure you that I don’t abide by Queensbury rules and have despatched a few hardened boxers from the ring on my travels. But I do consider myself as a fair and honest person. And maybe even a gentleman in the sense that you have implied it. As for a fossil, I see myself as a new generation of people who dare to disbelieve what is written and question everything and everyone, taking absolutely nothing for granted.

While engaging a pathologist on this same subject but in a different model if you get my drift, she said; “My god you have just dissected a body in front of me reassembled it and explained how it all works perfectly, and not even had to cut open a single cadaver.

Everyone in this forum is trying to help but you are at a considerable evolutionary disadvantage. It remains possible for the Gentleman Scientist to publish, but you simply must research others work and communicate in the right way. It's our rules now. Alternatively you can withdraw from competition, which is ultimately the safer thing to do.



And I really do appreciate being granted an opportunity to share my findings with people here!


:It's our rules now


Interpreted, as I don’t appear to abide by the rules?

:I remain true to my original offer, and make a second. If you are minded to look into other people's publications in the area, I will give you a list of journal articles that may get you started.



Withdraw from competition? Bahh, never knew how to be a quitter, but I can see that you are steering me into a rather complicated paper, which I believe may be the wrong way to go. I think it should be kept simple so that even a scientist can understand it. Present company excluded from that remark of course, and I really could use some help with this.

One last point, almost a week ago I set up a 2 metre vertical loop of tubing filled with boiled water with the two open ends submerged in two bottles of water to test the stability of gas free water. It has remained unaffected and is still intact. I will try to leave it for three weeks as Strasburger did with his tree experiment in picric acid to see if the constant tension causes cavitation without any added salt to the one side as in the Brixham experiment.

Regards Andrew
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #568

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Dave:
I think that a gentleman scientist can still do useful work, but this is very dependent on the area. In subjects that are studying the way the world is such as parts of zoology, geology, medcine and especially psycology there is a lot still to do - and anyone can find a new rock, animal or herb, however if you are in an area that has been intensely studied, the pickings are a lot poorer.

I would also say that the gentleman scientist is more likely to find an interesting experiment or new observation than come up with new theries of how the world works (again depending on the subject) as in parts of physics just understanding the evidence that you have to explain with your theory takes many years of work, let alone understanding the strengths and weaknesses of the present theories.

So essentially you are better off looking for new butterflies or rocks than rewriting quantumn physics.

I also think you are hugely underestimating the awkwardness of many scientists, a lot of them are really not the kind of people to fit in and take part in a conspiracy. Making lots of scientists do the same thing is a bit like hearding cats...

As to your experiments Andrew I can easily explain them by conventional physics apart from a couple of observations.

The not syphoning above a certain height.
and
The water retreating up the tubes when you remove them from the bottles.

I don't think that your explanations explain these any better than mine could so I am interested.

Have you made any form of systematic study of these phenomena? What height does the tube stop syphoning conventionally? does the water retreat up the tubes if the tube is shorter, or under less tension, or was layed out at an angle rather than vertically?
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #569

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So essentially you are better off looking for new butterflies or rocks than rewriting quantum physics?


No thanks; I have no desire to go chasing butterflies, any-more than I underestimate scientists.

As to your experiments Andrew I can easily explain them by conventional physics apart from a couple of observations.


The point really is the original thoughts, which led to the experiments, and is now leading to a paper compiled in such a way that it is beautifully simple, yet addresses all of the known idiosyncrasies inherent in the current theories.
To say that you feel that you can explain them by conventional physics is comforting, as I would expect this new paradigm to be understood by physicists and biologists. After all, the children and teachers in the schools I have demonstrated the experiments in, had no difficulty understanding this logic, any-more than the 3 thousand visitors to The London International Inventions fair did in 1997.

What I do find surprising is that no one here appears to have conducted the experiments for themselves in order to give a qualified account of their own observations. If it is the money, I will send the £3.00 so that you can purchase the tubing and T junctions. This is even more confusing when one would think that with so many young enquiring minds someone at least would want to see water flowing up a tube for themselves.

Have you made any form of systematic study of these phenomena? What height does the tube stop syphoning conventionally? does the water retreat up the tubes if the tube is shorter, or under less tension, or was laid out at an angle rather than vertically?


Not sure about what you mean by a systematic study. I have tried removing the tubes at lower than the thirty three feet limit and find that water flows out of the tube from one side only, lifting the entire contents up one side and out of the other. This was demonstrated to the children at High Week Primary school in Newton Abbot, Devon. They had difficulty understanding why water only flowed out of on end when the tubes were lifted.

I have tested the tube at an angle, a loop, partly horizontal and partly vertical, in an intricate multi directional set up, and it works the same. I.E. a flow and return is observed! But this is hardly surprising when this same flow is attributed to driving the Atlantic Conveyor system (Gulf Stream) where there are no tubes whatsoever. Like I said before, it has no respect for where it flows. But flow it must!
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #570

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Why is it that the phloem sap is observed to flow down, in the opposite direction to the predicted path of suction generated by the leaves? According to this theory, it is hard to understand how a plant or tree can differentiate between the xylem and the phloem. How can the same leaf suck up water in the xylem and blow it down the phloem at the same time? If you were to place an atomiser from a paint spray gun at the top of the tree, under say 65 psi, would you really expect this to cause water to be drawn up the tubes inside the tree? NO! It simply cannot work any more than a lift pump would work placed at the top of the tree. Why would you expect the current cohesion theory to work? You add, well there are many leaves at the top of the tree and the interactions between all of the leaves and the atmosphere would suffice to generate ample pull. How? There are many trees which have minimal leaves at the tops, like the larch which lift water with ease, yet do not have anywhere near the surface areas that you suggest would be required to generate the pull! Let alone Strasburger’s dead transpiring trees.

Even if you removed even more branches from the top of a larch it would carry on pulling water to the top! Look at bamboo for instance, or climbing vines.

A few days ago I went out with a stethoscope to listen to the trickling of sap as it flows in bulk within the trunk of an ash tree, which was just in bud. Again this tree did not have the massive surface area the cohesion theory requires of it. I could hear the water flowing and the cavitations creating cracking noises.

Now explain that with your knowledge of physics please,
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #571

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Rosy:
On the "Gentleman Scientist" question...
There is no particular reason, I don't think, why a "gentleman scientist" such as Andrew shouldn't be able to make and interpret accurately useful new discoveries many fields (I'd suggest that this wasn't infact the case in quantum physics which tends to require several miles of subterranean tunnels full of particle accelerators as this might be more than a little way outside the typical spare-time budget). It would require a phenomenal amount of dedication to get up to speed on the current thinking, getting hold of material not available on the internet etc., but some do have that.

However... the presumption within the scientific community is that individuals not doing this as a full-time job can't possibly have the time, energy and access to materials this requires, and so tend to be starting with an assumption that such people are unlikely to have anything very interesting to say. The primary necessity for anyone from an unexpected background who wanted to get their theory recognised by the scientific establishment is to write a *very* detailed explanation of their new theory along with a discussion of the old theory they're attempting to debunk which shows a very thorough understanding of the old theory such that it's impossible for readers to discount the whole exercise by saying to themselves "he only doesn't believe our theory because he doesn't understand it".
You haven't persuaded me yet. This may be because we're attempting to communicate in text and you haven't shown me any numbers, but I'm not convinced.

What I do find surprising is that no one here appears to have conducted the experiments for themselves in order to give a qualified account of their own observations. If it is the money, I will send the £3.00 so that you can purchase the tubing and T junctions.


Nope, not the money. The time. And the space. When I have more than a couple of hours together to call my own I have every intention of having a shot at some of your experiments. But as a student in a ground floor room in the middle of a seriously flat county this is not high on my list of priorities.

If you were to place an atomiser from a paint spray gun at the top of the tree, under say 65 psi, would you really expect this to cause water to be drawn up the tubes inside the tree?


I don't know how an atomiser from a paint spray gun works, but if it didn't introduce an air bubble or a nucleation site for a cavitation into the system I'd expect any given pressure to draw up a column of water of the corresponding depth... 1Atm vs a vacuum pushes water up 10m, as in a water barometer so my expectation would be that provided no cavitation occurs (and I'd suspect most conventional pumps in this area) a negative pressure of 2Atm would pull water up about 20m.
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #572

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Why is it that the phloem sap is observed to flow down, in the opposite direction to the predicted path of suction generated by the leaves?




Andrew fluid flows in the Phloem up down and sideways, it has been measured to be at a positive pressure - THIS MEANS IT CAN'T BE SUCKING UP THE WATER IN THE XYLEM DIRECTLY!! in order to suck the pressure in the phloem must be lower than the xylem..

If you read my previous post you would have found out that the reason it is at a higher pressure than the xylem is osmosis - the Phloem is sugary, and therefore water will osmosis into it from the xylem. This can happen at pressure differences of 10-20 atmospheres quite happily.

If you were to place an atomiser from a paint spray gun at the top of the tree, under say 65 psi, would you really expect this to cause water to be drawn up the tubes inside the tree?


If you made the atomiser out of something hydrophilic like paper or cotton and the holes in are small enough then yes.

Andrew HOW DO YOU KNOW WHAT AREAS ARE REQUIRED FOR THIS TO WORK? have you done any experiments or even calculations to find out - if so could I would be interested, if not please not don't make broad generalisations which you can't back up
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #573

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@ Dave
If you had read my previous posts, you would have found that this flow is not pressure dependent! It does not require pressure; it generates pressures as it flows! The tiny pulses of saline solution injected at the top of the loop experiment flow down. This causes a dragging effect because of the cohesive qualities of water. The downward flow cannot flow down without dragging water down with it. It behaves like an elasticised string. I.E. the downward flow is not possible, without it causing an upward flow! Phloem flows in the direction of a sink! If that sink happens to be an apple, then it will flow towards the apple, if it happens to be a root, it will flow to the root. If a denser solution is flowing down, then a less dense solution will be flowing up or in any direction affording less resistance! Hence “Flow and return”. In my inverted tubular experiment, both tubes are under a negative pressure with no saline added. Demonstrated by the water retreating up the tubes when the tubes are lifted out! Yet when the saline is added, it causes the contents of the whole tube to rotate in the direction of the downward flowing salt solution.

1. Evaporation cannot take place without it altering the density of the sap at the leaf!
2. Gravity will pull on the denser sap causing it to flow in the direction of a sink!
3. The denser sap will drag less dense solutions from other areas of the tree!
4. Pressures will be altered by this flow and return system, but the flow itself is not pressure dependent. I.E. Pressure changes are not required to cause this flow in any direction, other than the effect of gravity upon dense sollutions!
5. The flow and return will generate negative pressures and tension in the sap at the roots and throughout the xylem it will generate an upward pull on the water, which will cause water to flow horizontal, down, up and diagonally, because the water is being dragged upon by the falling solutes and in the phloem it will inevitably change the negative pressure to a positive pressure, causing both a pushing force in front of it and a pulling tension behind it.
6. In the tree, there is an outer sleeve, which adds additional support for this flow and return, making it much more robust than the simple inverted U tube experiment. Within this sleeve / bark cavitations can occur frequently and do not interfere with this flow and return system. The sap simply flows around the gas bubbles, as observed in my own tubular experiments.
7. In these tubular experiments, it was also observed that a two-tier flow system can exist in a single tube, meaning, that there is a flow and return observed in the same side of a closed loop of tubing. Meaning, that a concentrated solution flows down one side of a diagonally placed loop of tubing, while clean water flows above it in the opposite direction!

For you to keep dismissing this as irrelevant to trees, without observing the hard evidence for yourself is a reaction I have grown to expect from people who would rather believe text in text books, than to question and evaluate the theories for themselves. You have absolutely no idea of the full implications. I have lived and loved my work and will do so until the day I die!

I therefore decline your polite invitation to become self gagged and hope you will understand why.

Andrew
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #574

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Dave:
Yes your system generates it's own pressure differences however the water is still moving because of pressure differences they are just generated by density differences not by a pump..

Shall we do a little calculation...

if you inject 20cm of saline with a density of 1.5g/cm3 this will produce an extra pressure of about (1000kg/m3-1500kg/m3)*.2m*9.81 = -1000Pa or -.01Bar above the saline on the downwards side.

So for a little overview:
The pressure at the top of a 20m tube on the no saline side is -1Bar
on the saline side it is -1.01Bar because of the extra weight of the saline pulling on it.

This means that at the top the pressure on the saline side is lower so water moves towards the saline side - as you have observed.


However if you measure the pressure of the fluid in the Phloem
www.pubmedcentral.nih.gov/pagerender.fcg...d=440496&pageindex=1
you find the pressure is positive and up to 10 Bar - (otherwise aphids would implode)

So lets think about this -

the pressure in the xylem is at up to -10Bar the pressure
in the Phloem it is at +10 Bar.

Now you are expecting me to accept that the water is moving against a pressure difference of 20Bar to flow into the Phloem with no Osmosis going on...?

For you to keep dismissing this as irrelevant to trees, without observing the hard evidence for yourself is a reaction I have grown to expect from people who would rather believe text in text books, than to question and evaluate the theories for themselves. You have absolutely no idea of the full implications. I have lived and loved my work and will do so until the day I die!



Please do not say that I am ignoring the hard evidence - at no point have I said that there is much wrong with your experiments - they are exactly what I would expect to happen apart from a few minor details that you have not investigated in detail.

What I am disputing with you is your interpretation, as although on the surface it sounds nice if you had bothered to do any simple calculations - like how much energy is released by the sap going down compared to the 50x more water going up, looked at the actual structures in a plant, considered what the pressure is in the Phloem, considered that sugar flows in more than one direction in a plant, etc. you would have realised that unless a tree is a perpetual motion machine, and is not designed the way it appears to be it can't work the way you describe.

The most important question I have to you despite all this, is have you ever considered that you may be wrong? or preferably tried to prove yourself wrong. As if you haven't you are not doing science but PR.
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How do Trees Really lift Water to their Leaves? 7 years 10 months ago #575

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Inside a phloem, the structure adds an additional restrictive force on the downward flow, mainly friction, causing the falling solutes to back up, “Hydraulic brake”, slowing the flow down, and allowing sugars and salts to accumulate, giving rise to higher pressures. Inside the tree, as previously explained, there is additional support for the columns of water, due to the outer sleeve of the tree. This will inevitably explain the reductions in negative tension found inside the tree, as opposed to those that are obvious inside the Brixham Experiment. For instance, If I were to use a closed loop of tubing instead of the open ended tubing in the Brixham Experiment, then the height that can easily be obtained would exceed even the tallest of trees, and the circulation generated by the solutes would effortlessly rotate the fluids in the direction of the density path. Again the support of either a closed loop or a semi-closed loop changes the pressure parameters greatly.

In your calculations, I have difficulty understanding how you have derived the figures.

I believe you will find that the negative tension inside the inverted U tube at 20 metres will be far higher than your estimate. And as you are aware, the experiment is designed to demonstrate the flow, not to mirror the internal structure of a tree. So comparing like for like with the inverted tube is pointless.

See Reference to Professor H.T.Hammel letter page 2 of this thread.

The most important question I have to you despite all this, is have you ever considered that you may be wrong? or preferably tried to prove yourself wrong. As if you haven't you are not doing science but PR.[/quote]

With this last question, it would appear that you are trying to belittle me. Why is this? Do you not think that given all of the years I have been working on this, I have not tested and re-tested as to whether I am correct or incorrect?
E.G.
One simple test for you:

Measure the density of your urine, making a note of what you have eaten and drank during the day. Retire to bed, and measure the density of your urine when you relieve yourself in the morning.

Now elevate your bed by no less than six inches or fifteen cm’s at the head end and repeat exactly as the day before.

Then sleep with your head down and your feet up on the same incline and do the same. Now compare the figures and explain why there are massive differences in urine density.

Also, if you have varicosity in the lower limbs, you might find that the veins are pulled in by the reduction in pressure inside the veins, as we did when sleeping with the head end elevated for four weeks. Strange, because the vein in my wife’s leg had been bulging and aching for 16 years, following the birth of our first child. The vein is no longer varicose and barely visible!

You will find that your heart rate will reduce by 10 to 12 beats per minute, and your respiration rate will reduce by 4-5 breaths per minute, even if you are a sleeping bull terrier! But you will need a partner to measure these while you are sleeping.

Most of my research since discovering this flow and return has been directed towards helping people suffering from a whole range of illnesses. Like I said before, this flow and return has no respect for where it flows, but flow it must! I have spent many years working with and helping people with neurological and non-neurological conditions, to which, I have never charged a single penny for my services.

However, discussing this physiology and its wide ranging relationships will only serve to complicate this discussion beyond the purpose of plants and trees, and I have absolutely no wish to do so, other than offering this as an excuse for not conducting a greater number of various experiments with water and tubes. I have found myself going full circle and addressing the foundations of the initial discovery, which is to show how the bulk flow is generated, how it circulates and how evaporation triggers it.

As for P.R. I have appeared on television 3 times, been featured in the Daily Mail, Western Morning News, BBC and independent radio, Woman’s Realm magazine, Herald Express, Sunday Independent, Disabled Bikers Magazine, Medical Physics Group Newsletter at The Institute of Physics. Why would I want to be doing P.R. on the Naked Scientists forum? I find this remark of yours a little terse.

I am here because I am trying to understand what is required of me to publish a paper that will provide the “Closed Shop Scientific and Medical Communities with a paper that is difficult for publishers and readers to ignore, and believe it or not, I am gaining a tremendous insight into how this is to be achieved. And perhaps enlist a little expert help.

Andrew
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