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Author Topic: How do Trees Really lift Water to their Leaves?  (Read 244712 times)

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #125 on: 26/05/2005 10:58:00 »
Rosy



 
quote:
Atmospheric pressure will support a 10m column of water. This will give a vacuum pressure above the water (0Atm) We know that. (I think?)


If you are referring to the barometer type experiment, the only reason the water remained in the tube was because of the ability of water to stick to the top of the capped tube and the friction to the internal walls of the tube, again adhesive (adhesive quality of water) Atmospheric pressure does contribute to the experiment but not as much as believed, demonstrated by the inverted U tube, which relies on the cohesive force of water, more than doubling the height achieved and therefore indicating that adhesion was the principle factor in the barometer type experiment. When the water level goes below the 10 M level in the Barometer type experiment, it is then supported by a vacuum.

In the Inverted U tube experiment, there is twice the weight applied to the column of water suspended over the raised middle of the tube, and therefore twice the amount of tension is applied to the water inside the tube, yet it remains relatively stable providing the gas has been removed from the water by pre-boiling it.

The pull from above is balanced by the equal opposing pull on the opposite side of the tube, which therefore is a not actually a pull from above, more an increase in tension.
Again atmospheric pressure plays a part but not as much as previously thought. More, the Cohesive strength of water is tested against the adhesive strength of water + the additional friction caused by the additional adhesion to the doubling of the length of tube compared to the single vertical tube.

I conducted another experiment at 2 metres elevation, This involved 3 lengths of tube connected to a central T Junction, one length was longer than the other 2, to allow the open end to be doubled back on itself into a U shape, again with the end open and the water level inside to be at the same level as the water level in the jug which contained the other two open ends of the triple conduit. The U ended tube was allowed to fall below the water level in the jug containing the otehr two open tube ends ends. The whole experiment was filled with pre-boiled water and great care was taken to make sure there were no leaky joins where air could be sucked in.

What would you, or anyone else reading this expect to happen to the water in the end exposed to the atmosphere via the U shaped exit point, and the central T junction was elevated to 2 metres vertical?

With regards to constructing an experiment to show that water can be excreted from a tubular construction, Strousburger already did it by killing the tree and observing water transpiring from the leaves for three weeks after the death of every living cell in the tree, making the trees tubular structure a perfect example of your challenge! And in doing so concluded that bulk flow was not a living process, but a Physical non-living process! I am tempted to repeat his truly fascinating experiments myself.

Andrew



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Offline Terry Richards

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Re: How do Trees Really lift Water to their Leaves?
« Reply #126 on: 26/05/2005 12:54:37 »
I have been reading this thread and thought I might add that I was at the London International Inventions show in 97 and saw the experiment on display at Andrewís stand. It was remarkable. From what I remember he had a dark red coloured liquid, which was salty water and dye in a simple loop of tubing suspended on a board with bags. Although I didnít fully understand the explanations he gave, the water did appear to be flowing up and down.

He was showing a bed that was tilted. I didnít stay to the end of the show to see if he won anything for his invention, but the experiment was impressive.

Terrence
 

Offline rosy

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Re: How do Trees Really lift Water to their Leaves?
« Reply #127 on: 26/05/2005 22:09:16 »
Andrew, I hope I'm about to explain some things you already know. But it's not at all clear from your posts that you do understand this stuff. I'm not going to consider the effects of introducing different densities of liquid, because that merely confuses the issue.
I don't think you should be disagreeing with me on any of the points I make here.

The basic point about a liquid such as water is that the pressure at a given depth is constant for any interconected bodies of water (where each is free to flow into the other.
So if equal pressures act on both side of a U tube open at both ends, the water in the two tubes will be at the same level.

If we then take out some of the air on one side (say reduce the pressure to half an atmosphere) then the water on that side will be pushed through the system by the air pressure on the other side until the system is balanced again. At this point, the pressure in the water on the other (lower pressure) side, at the same level, will also be 1 Atm. This will be due to (i) a pressure of 0.5 Atm from the gas and (ii) an extra weight of water, which will be enough to give 50kPa per square metre (as water weighs in at 1000kg per metre cubed, so a metre depth of water exerts a pressure of about 100N per square metre=100Pa) so the depth of the water will be 5m higher on one side than the other for a 0.5Atm air pressure difference.

quote:
When the water level goes below the 10 M level in the Barometer type experiment, it is then supported by a vacuum.


This is entirely untrue. The water is not supported by the vacuum in a barometer, it is pushed up by air pressure at the water level of the open vessel which gets it up to a height of 10m under compression. The vacuum cannot provide *any* force on or against *anything* because THERE'S NOTHING THERE, it's just a total absence.

Up to 10m, nothing has to be supported under tension *at all* because it's all happening at positive pressure.

quote:
In the Inverted U tube experiment, there is twice the weight applied to the column of water suspended over the raised middle of the tube, and therefore twice the amount of tension is applied to the water inside the tube, yet it remains relatively stable providing the gas has been removed from the water by pre-boiling it.

Um, no. In an inverted U-tube less than 10m in height there is no tension at all, it's all happening under positive pressure, just less than atmospheric. There's quite a large difference between the two [1] (provided there's no other way of air at atmospheric pressure seeping into the system). The pressure in the two tubes at any given depth will be the same. If there is space for it to do so, the water wants to move from high to lower pressure, which is how a syphon works- if pressure is 1Atm at a point on one side of the system and at some open point lower down on the other side there will be a positive pressure greater than 1Atm at that point. In which case, if it is open to the air, water will be pushed out of the system against the 1Atm pressure.
Above 10m, provided no cavitation occurs, the same will apply. Pressure falls constantly all the way up, and negative pressures "pull" exactly the same in all directions... against the walls of the tube, against neighbouring "bits" of water and so on.

quote:
Strousburger already did it by killing the tree and observing water transpiring from the leaves for three weeks

My point is that I think that your demonstration system requires more weight coming down than going up (weight of water plus weight of solution). This is very obviously not true of a tree and doubly untrue of Strousburger's dead tree which is no longer synthesising sugars.
If you can't build a demonstration then an account of a back-of-an-envelope calculation accounting for the energy and mass transferred (what's going where and what's powering it) might serve equally well to convince me.

quote:
What would you, or anyone else reading this expect to happen to the water in the end exposed to the atmosphere via the U shaped exit point, and the central T junction was elevated to 2 metres vertical?

I have no idea... I don't understand your description. Any chance of a diagram?



[1]100kN per square metre is about equivalent to 10,000 kg. The oft-quoted comparison for this is that it's equivalent to the weight of one elephant per metre cubed.
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #128 on: 26/05/2005 23:21:40 »
Terry
Thank you so much for the post Terry, Smiling like a cheshire cat here :) Though probably won't remember you from the exhibition :( Was a great few days for me, my son and my friends who attended. I did win a Thousand pounds worth of free advertising in Streetwise Magazine and there was a nice feature in there about the experiments and theory behind the bed design.


Rosy
A simple thought experiment for you to consider Imagine the inverted U tube experiment set up, but this time, the two open ends are submerged in one sealed container, with the water level afording some air space above it. And it has all the pressure removed eliminating any positive pressure or influence from the atmosphere.

Prediction, the water column will remain intact. What do you think?   B.T.W thinking about a way of testing this one to settle an argument.

In the case of the barometer type experiment, "Thought experiment again unfortunately" removing the poitive pressure in this experiment by sucking the air out of the beaker containing the water with the open end of the capped water filled tube will indeed cause the water to be pulled from the top of the capped tube at a much lower height than ten metres. But this does not prove that the pressure was the only force supporting it. It suggests that the increased downward force of the water has severed the hydrogen bonds to the capped glass tube.

I was trying to refer to the way a syringe pulls water up, even when there is air space directly in front of the plunger. The absence of pressure if you like is sufficient to draw water up acting upon its surface, so why do you think the vacuum is any different to the suction caused by the plunger in a syringe?

Maybe its the way I explain it?

Andrew

"The explanation requiring the fewest assumptions is most likely to be correct."
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Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #129 on: 26/05/2005 23:44:38 »


Rosy

I forgot to add that Strasburger's experiment (killing the tree) caused a cascade of solutes to flow down from the inevitable decay of the foliage and internal cells. According to my theory this would be more than enough to cause the flow and return to carry on for three weeks or more. The solutes did not vanish suddenly along with the death of the tree, they remained at an elevated point and were released slowly. I think Strasburger may have even noticed an increase in the circulation of the dead tree during the rapid release of stored sugars and salts.

I really don't relish killing a tree for science to test this, being a tree hugger by nature, I like planting trees not destroying them.

If i purchase a digital camera and video the experiments would this be acceptable to you and others? Seeing as no one can be bothered to repeat them. I have the original Brixham exp on video also, maybe I can find a way to load it on to a website.

Andrew

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Offline daveshorts

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Re: How do Trees Really lift Water to their Leaves?
« Reply #130 on: 27/05/2005 00:55:41 »
quote:
A simple thought experiment for you to consider Imagine the inverted U tube experiment set up, but this time, the two open ends are submerged in one sealed container, with the water level afording some air space above it. And it has all the pressure removed eliminating any positive pressure or influence from the atmosphere.


By eliminating any positive pressure do you mean carrying out the whole experiment in a vacuum? as otherwise there will allways be a positive pressure. You can't do this with open ends to the tube as it would cause the water to evaporate at the ends quite quickly...

quote:
Prediction, the water column will remain intact. What do you think? B.T.W thinking about a way of testing this one to settle an argument.


If you could somehow do it without exposing the surfaces to a vaccum and none of the surfaces were hydrophobic to act as nucleation sites it probably would remain intact - if you ignore the bottom 10m of your experiment that is essentially what you have done.

You could build your 2m loop and attach syringes to the end and pull on the syringes with a force of 100 000N x Area of syringe in square meters (so for a syringe with an area of 1cm2 apply a force of 10N or about 1kg. This would be equivalent to doing the experiment in a vacuum as the weights on the syringes should be compensating for atmospheric pressure.

As a check try it with and without a tiny bubble in the system, if when you add the bubble the weights pull the plungers out but when you don't have a bubble they don't, I think it has shown what you want to.

quote:
In the case of the barometer type experiment, "Thought experiment again unfortunately" removing the poitive pressure in this experiment by sucking the air out of the beaker containing the water with the open end of the capped water filled tube will indeed cause the water to be pulled from the top of the capped tube at a much lower height than ten metres. But this does not prove that the pressure was the only force supporting it. It suggests that the increased downward force of the water has severed the hydrogen bonds to the capped glass tube.


If you are using very clean and boiled water I expect that you could support a column higher than 10m in a glass tube, and I am sure it is possible using the tubes you do - as long as you can fill the end of the tube with no bubble or with something that has holes so small that sufrace tension can support the pressure - a tree.

  the ten metres thing does however hold if you are using large tubes with dirty and unboiled water as once there is a bubble the water will cavitate if there is a negative absolute pressure.

But this is all dead standard cohesion theory...

quote:
I was trying to refer to the way a syringe pulls water up, even when there is air space directly in front of the plunger. The absence of pressure if you like is sufficient to draw water up acting upon its surface, so why do you think the vacuum is any different to the suction caused by the plunger in a syringe?

The reason that a syringe can suck even with a bubble in it is that everything is under atmospheric pressure 100 000Pa - the equivalent of 10m of water.

so if the water in the syringe is under a pressure of 100 000Pa and the fluid in the syringe is under pressure of 90 000Pa there will be a NET force towards the syringe and liquid will flow in, without having a negative absolute pressure anywhere.

I think you will find that the syringe will not suck if there is a bubble and you are working against more than 10m of head - again you are in a good position to try this.
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #131 on: 27/05/2005 22:03:37 »
Dave, you have made some interesting points, and I have taken on board your idea about a syringe and a kilo weight. Great idea if the syringe can deal with a kilo force in the opposite direction to its designed function, but its certainly worth a try.

By the way, if the inverted tube is at 2 metres and the ends submerged in water at equal lengths, filling one bottle higher than the other causes it to flow to the other bottle as expected. From what I remember this was not the case at over the 33 feet limit. But I will have to test again at some point to make certain. Also, at 2 metres using the salt, it does not return to the other side because of the increased density of the salt receiving side. I have not observed the coloured salt solution flowing back up the tube once it has reached the bottle and the tube contains clean water. Also, you can regulate the flow by altering the density on the rising side bottle. This is important, because it suggests a mechanism for acid rain to kill trees by altering the density of the ground water by dissolving a greater amount of minerals from the soil. It should be easy to test this by adding salt solution to the soil, and then adding distilled water to compensate for the increased salt to see if it allows the plant or tree to recover. This also fits with overfeeding plants and killing them.

Thanks for the suggestions

Andrew

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Offline daveshorts

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Re: How do Trees Really lift Water to their Leaves?
« Reply #132 on: 29/05/2005 12:04:31 »
Cool, just be a bit careful about the design of your experiment, as if you are attempting to distinguish between two hypothesies you have to be careful that the result will be difficult in the two hypothesies. I think adding a lot of salt to the ground would kill the tree in the conventional model as it would tend to dessicate the roots by osmosis...

Out of interest what do you mean by return to the other side? It is hard to describe this sort of thing without a diagram... Do you mean that in teh long tube the flow overshoots and then afterwards flows backwards for a bit?
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #133 on: 29/05/2005 19:52:56 »
I have drawn a diagram of the triple tubed exp, but can't figure out how to post a picture on the site, that on my hard drive :(

The last post was refering to the single looped tube exp.

According to the results in the single loop tube, it should only require a relatively small amount of salt to upset the flow, when added to the rising tube side. However, the tree has a fair amount of sugars and minerals in the sap and stored in the leaves, branches and trunk. So the salt may cause the leaves to wilt, but it may not kill the tree for a long time. just wandering if anyone has done something similar with trees and posted on the net?

Got my eye on a cannon Ixus 700, to film the experiments, but they cost over £300 with a decent memory card and tripod. But feel it will be well worth getting a good camera with high movie resolution.

It's about time I made a web page so I can store the pictures on it, tried using a blog, but the pictures still do not show on here for some reason.

 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #134 on: 30/05/2005 10:48:22 »
Trees the key to beating salinity
DAFF04/175M 18 August 2004

The Australian Government's Natural Heritage Trust will invest $2.9 million over two years to develop commercial environmental forestry (CEF) that will address salinity.

Speaking at a regional forest investment workshop in Morwell, Australian Forestry and Conservation Minister Senator Ian Macdonald said the CEF program developed farm forestry systems that reduced salinity while delivering commercial returns.

"It is about linking the commercial to the environmental to develop long-term agricultural business options for farmers affected by salinity," Senator Macdonald said.

"When adopted, CEF will also benefit the broader community by not only reducing salinity in the Murray system, but also by protecting water quality and biodiversity. The CEF project supports private and public outcomes for regional catchment management groups and private investors to deliver benefits."

The CEF project began in 2003, and is a major collaboration between CSIRO and the Australian Government Department of Agriculture, Fisheries and Forestry. Other partners include the National Association of Forest Industries, the Murray Darling Basin Commission and the Victorian Department of Primary Industries.

The project partners will invest more than $4 million in 2004-05, and plan further investment in 2005-06.

The project is focussed initially on a pilot in the Goulburn Broken Catchment where salinity is a major problem, and the Catchment Management Authority (CMA) has targeted forestry as a potential solution. The CMA is an active partner in the project and is holding community forums to involve landholders.

The project has identified those areas in the catchment where forestry will reduce salinity without stressing river flows. These areas are typically found where rainfall and growth rates are lower than in traditional plantation areas. CSIRO is undertaking research to reduce investor risk by identifying species with commercial potential for these lower rainfall areas and developing growth predictions for them.

The project is also quantifying the other environmental benefits of farm forestry of interest to regional NRM groups and governments. These include biodiversity conservation, carbon sequestration and erosion control.

"This new funding of $2.9 million comes on the back of initial seed funding of $550,000 provided last year," Senator Macdonald said.
http://www.mffc.gov.au/releases/2004/04175m.html

Response of orchard 'Washington Navel' orange, Citrus sinensis (L.) Osbeck, to saline irrigation water. II. Flowering, fruit set and fruit growth.

H Howie and J Lloyd

Abstract
Flowering, fruit set and fruit growth of 'Washington Navel' orange fruit was monitored on 24-year-old Citrus sinensis trees on Sweet orange rootstocks that had been irrigated with either 5 or 20 mol m-3 NaCl for 5 years preceding measurements.Trees irrigated with high salinity water had reduced flowering intensities and lower rates of fruit set. This resulted in final fruit numbers for trees irrigated with 20 mol m-3 being 38% those of trees irrigated with 5 mol m-3 NaCl. Final fruit numbers were quantitatively related to canopy leaf area for both salinity treatments.Despite little difference between trees in terms of leaf area/fruit number ratio, slower rates of fruit growth were initially observed on high salinity trees. This effect was not apparent during the latter stages of fruit development. Consequently, fruit on trees irrigated with 20 mol m-3 NaCl grew to the same size as fruit on trees irrigated with 5 mol m-3 NaCl, but achieved this size at a later date. Measurements of Brix/acid ratios showed that fruit on high salinity trees reached maturity standards 25 days after fruit on low salinity trees.Unimpaired growth of fruit on high salinity trees during summer and autumn occurred, despite appreciable leaf abscission, suggesting that reserve carbohydrate was utilized for growth during this period. Twigs on high salinity trees had much reduced starch content at the time of floral differentiation in winter. Twig starch content and extent of floral differentiation varied in a similar way when examined as a function of leaf abscission. This suggests that reduced flowering and fruit set in salinized citrus trees is due to low levels of reserve starch, most of which has been utilized to support fruit growth in the absence of carbohydrate production during summer and autumn.

Keywords: Oranges, irrigation, water, salinity, responses, fruits, set, development, flowers, initiation, Carbohydrates, metabolism, Polysaccharides, Flowering, growth, Maturation, subtropical fruits, citrus fruits, fruit crops, Citrus, Australia, Rutaceae, Sapindales, dicotyledons, angiosperms, Spermatophyta, plants, Australasia, Oceania, 2180,

Australian Journal of Agricultural Research 40(2) 371 - 380
http://www.publish.csiro.au/nid/40/paper/AR9890371.htm

Salinity and drought stress effects on foliar ion concentration, water relations, and photosynthetic characteristics of orchard citrus.

JP Syvertsen, J Lloyd and PE Kriedemann

Abstract
Effects of salinity and drought stress on foliar ion concentration, water relations and net gas exchange were evaluated in mature Valencia orange trees (Citrus sinensis [L.] Osbeck) on Poncirus trifoliata L. Raf. (Tri) or sweet orange (C. sinensis, Swt) rootstocks at Dareton on the Murray River in New South Wales. Trees had been irrigated with river water which averaged 4 mol m-3 chloride (Cl-) or with river water plus NaCl to produce 10, 14 or 20 mol m-3 Cl- during the previous 3 years. Chloride concentrations in leaves of trees on Tri were significantly higher than those on Swt rootstock. Foliar sodium (Na+) and Cl- concentrations increased and potassium (K+) concentrations decreased as leaves aged, especially under irrigation with 20 mol m-3 Cl-. Leaf osmotic potential was reduced as leaves matured and also by high salinity so that reductions in leaf water potential were offset. Mature leaves had a lower stomatal conductances and higher water use efficiency than young leaves. After 2 months of withholding irrigation water, leaves of low salinity trees on Tri rootstock had higher rates of net gas exchange than those on Swt rootstock, indicating rootstock-affected drought tolerance. Previous treatment with 20 mol m-3 Cl- lowered leaf area index of all trees by more than 50%, and resulted in greater reserves of soil moisture under partially defoliated trees after the drought treatment. This was reflected in more rapid evening recovery of leaf water potential and less severe reductions in net gas exchange after drought treatment in high salinity trees on Swt rootstock. High salinity plus drought stress increased Na+ content of leaves on Swt, but not on Tri rootstocks. Drought stress had no additive effect, with high salinity on osmotic potential of mature leaves. Thus, the salinity-induced reduction in leaf area appeared to be independent of the Cl- exclusion capability of the rootstock and decreased the effects of subsequent drought stress on leaf water relations and net gas exchange.

Keywords: Oranges, salinity, responses, rootstock scion
http://www.publish.csiro.au/nid/40/paper/AR9880619.htm

Salinity

Cause

Salinity damage is caused by the accumulation of toxic levels of salts (sodium and/or chloride) in the tree. This usually arises from the use of saline irrigation water or the presence of a saline watertable within or just below the rootzone.

Symptoms

The severity of symptoms increases with the concentration of salts accumulated in the soil and/or trees. Loss of tree vigour is a major symptom of salinity. Trees affected by salinity generally show water stress before they should, ie when soil moisture content appears adequate. This is particularly the case where salt has accumulated in the soil.
Marginal leaf burn, particularly towards the tips, is characteristic of salinity. Leaves tend to be cupped. Premature drop of a proportion of the older leaves may occur along shoots.
When cut off, the branches of salt affected trees have discoloured heartwood.
In severe cases salinity causes tree death.

Control

Leaf nutrient analysis is a useful means of detecting the development of salinity problems. Annual leaf analysis will reveal the trend in leaf sodium and chloride levels. If levels are increasing the cause of this should be investigated. Bear in mind that higher levels can be expected in low rainfall seasons and in years of higher than normal river salinities.
The water used for irrigation in the Riverland is relatively saline, normally in the range 400 to 800 EC. With adequate irrigation management and good drainage, these levels of water salinity need not substantially affect stone and pome fruit production.
Leaching of salts through the soil profile is a necessary part of irrigation in the Riverland to prevent salt accumulation in the rootzone.
For further information refer to the irrigation section.



Knowledge of the problem?
Observations of increasing land and stream salinity were first reported many years ago. In 1907 Government Analyst E. A. Mann suspected that there was a relationship between clearing and the development of land salinity.

In 1902, 8,000 ha of trees in the Mundaring Weir catchment were ringbarked to increase run-off. Salinity in the weir increased, and in 1909 it was recommended that regrowth be encouraged and replanting undertaken. This was done and salinity levels fell.

Increasing salinity in railway dams used to supply water to steam engines was also observed. A railway engineer, W. E. Wood, collated and analysed the early data and with the publication of his paper in 1924 the relationship between clearing and increased land and stream salinity was unequivocally established.
http://agspsrv34.agric.wa.gov.au/environment/salinity/intro/salinity_at_a_glance.htm

Dave, this does appear to fit with the saline regulation of the tubular experiment, where the saline sollution isadded to the rising tube side bottle.

But more to the point, it was because of my interest in irrigating deserts and reforesting them that I considered how the trees were dealing with salts in the first place. I have contacted the Australian Government and several experts on desertification many times over the years, but failed to touch a nerve. Now trees are being recognised as valuable desalination plants.

This is good news for me. I have been shouting this message at them since 1993. "Plant Trees to reduce salinity in the ground water" I am curently shouting a similar message to the people in Thailand, who are experiencing one of the worst droughts in their History.
http://www.thaivisa.com/forum/index.php?act=Post&CODE=02&f=18&t=29285&qpid=358136


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Offline qazibasit

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Re: How do Trees Really lift Water to their Leaves?
« Reply #135 on: 10/06/2005 10:35:26 »
its mainly due to ascent of sap.
 

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Re: How do Trees Really lift Water to their Leaves?
« Reply #136 on: 28/06/2005 22:40:44 »
Mangrove trees, which grow in salt water, so something oppositee. They take in salty water and deposit salt crystals on the surface of their leaves. Surely, the difference in ion concentration is a crucial factor in both situations.

R A Beldin,
Improbable Statistician
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #137 on: 07/08/2005 10:52:22 »
R.A. Beldin

Mangrove trees are able to restrict the amount of salt they take in and the salts found on the leaves are a result of evaporation, re-concentrating the salts. The difference in ion concentrations is indeed a crucial factor in all situations. Wherever a concentration takes place due to evaporation there is an obvious alteration of density in the fluids that are shedding water. There has to be! Denser solutes at the evaporation points will inevitably be acted upon by gravity and there goes that for every action there is a reaction again. Gravity will pull the denser solution down and the negative tension behind the falling sap will draw up less concentrated solution as a return flow, much the same as a flow and return system in a central heating boiler, which uses heat to alter density on the rising side and the cooled water becomes denser so provides the return flow. Having fitted this type of boiler it contributed to the discovery.  Flow and return hot water supply drawings. http://www.gasman.fsbusiness.co.uk/system_basics.htm http://www.ecoplusonline.com/images/Fig5_70.gif


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Offline robbyn

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Re: How do Trees Really lift Water to their Leaves?
« Reply #138 on: 08/08/2005 13:10:42 »
I am interested to learn if there is more evidence supporting Andrew's view that it is best to sleep on a slight decline. Since 1998 is their further emperical evidence in support of the claim? Have their been any tests undertaken in controlled circumstances?

In his 1998 article he explains that "Cattle and sheep, when given a choice all sleep facing uphill". To me this reads as if they prefer to sleep on an incline.

Hospital beds in order to encourage sluggish circulation and avoid thrombosis are designed to raise the feet above, not lower them below, head level. I assume the benefits of this have been endorced by hundreds of years of practical observation.

Andrew makes some big claims  for sleeping on a decline of 5 deg. As the benefits claimed are considerable I would appreciate an update, so I can decide if I should copy it.

Robin
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #139 on: 08/08/2005 15:22:00 »
Hi Robbyn

I have been trying to enlist the cooperation of the medical profession since 1994, lots of broken promises, despite having convinced quite a few people within the health service that this would save them an awful amount of money and time, not to mention saving patients limbs and lives.

I am currently trying to get a simple study with varicose veins oedema and leg ulcer underway at the local prison. The Health Officer there is very interested and we have the support of a vascular surgeon from Torbay Hospital and Professorís Urnst and Curnow, also invoved with local health service and universities.

 The case histories are from my own attempts to demonstrate just how effective this simple cost free therapy is.

My telephone no is +44 1803524117 should you wish to hear this from the horses mouth, or have any questions which require answers.

Sincerely   Andrew K Fletcher

Below is a thread where I have been asking on here for some help to conduct a study that will be accepted by the medical profession.
http://www.thenakedscientists.com/forum/topic.asp?TOPIC_ID=2262

"The explanation requiring the fewest assumptions is most likely to be correct."
K.I.S. "Keep it simple!"
 

Offline robbyn

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Re: How do Trees Really lift Water to their Leaves?
« Reply #140 on: 08/08/2005 20:28:26 »
It seems there are two things to investigate:

1. The pumping action of a tree. Is it gravity aided?
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I notice that you were invited to put together a page length paper for a peer reviewed journal. I would suggest you follow that advice.

2. The medical benefits of sleeping on 5deg declined bed
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I have read the testimonials you kindly sent to me. They are remarkable and the results astounding. I can understand you wanting to pursue this discovery. It may be that the gravity theory does not account for the results. I am not qualified to comment. I know that many discovers of medical breakthroughs were broken by the system demanding explanations rather than results. I do not understand why bed manufactures are not happy to finance a study.


Robin
 

Offline Jason Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #141 on: 10/08/2005 02:44:23 »
Its about time they started to give u some constructive comments dad! ive been watching these threads for a while now :D
I have watched and heard and seen thousands of people from doctors, proffesors, scientists to journalists and lamers on the net try to rip into my dad for years and try to take down his ideas and accomplishments and have all failed miserably .... he will get recognised in the end ya know!!! jus keep motoring on dad!!! .. why is it so easy to spread bad news and it is so difficult to bring a ray of light to the world?

Jason
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #142 on: 18/10/2006 08:39:52 »
As we now have quite a few new members, it might be worth taking another look at this theory and hope you will forgive me for bumping this subject up.

Andrew

"The explanation requiring the fewest assumptions is most likely to be correct."
K.I.S. "Keep it simple!"
 

Offline Wade

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Re: How do Trees Really lift Water to their Leaves?
« Reply #143 on: 11/02/2007 23:43:43 »
It looks to me like the answer would lie in the active transport of cells... and that if the tree is completely dead when the water moves upward, something is pushing it. perhaps it is the process of death and decomposition that pushes the water upward into the leaves, if, for instance, the circulatory pathways  harden and move water upward as they dry up. i admit, I only started researching tree circulation today, and except, of course, for photosynthesis, i have almost no knowledge of the anatomy of a tree, but i do know a significant amount about physiology and this entire topic seems to me like way too much energy put into something that could be found out with a little research. although i admit, i haven't read the entire topic either.
« Last Edit: 11/02/2007 23:50:17 by Wade »
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #144 on: 24/08/2007 20:20:02 »


The Experiment at Brixham Overgang Cliffs where water flowed vertical up a single 6 mm bore tubing using 10 mils of salt solution, demonstrating that a tiny amount of denser solution can lift effortlessly many thousands of times itís own volume in water without any artificial aids, demonstrating clearly a non living physical cause of bulk flow in plants trees, animals and humans. The 10 metre limit for lifting water clearly needs some serious revision.

Online experiment details
http://www.metacafe.com/watch/786493/water_flowing_up_a_cliff_to_24_metres_with_no_pump_experimen/#

http://www.myspace.com/inclined_bed_therapy
« Last Edit: 29/08/2007 15:04:13 by Andrew K Fletcher »
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #145 on: 05/09/2007 19:08:40 »
http://www.metacafe.com/channels/AndrewKFletcher/

Just added the scaled down version of the Brixham experiment on metacafe and the set up instructions for the experiment as parts 1 and 2, followed by actual footage of the experiment in Brixham in 1995, seems such a long time ago now, particularly when the evidence provides irrifutable facts, one can't help wondering why it has been resisted for so long.

This short video shows how water is raised using salt solution it also shows negative tension pulling a filled syringe body plunger in. But most of all it shows the velocity of this flow system in realtime.
« Last Edit: 05/09/2007 19:10:13 by Andrew K Fletcher »
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #146 on: 21/09/2007 10:59:49 »
Rosy, have you seen the experiments on metacafe yet? Take a look at the scaled down version of the Brixham Experiment, here you will see a syringe filled with concentrated saline sollution being sucked up under a negative tension. The weight of the salt +resistance of the syringe body shows there is a negative tension in the water and the same happens without salt sollution. Mentioning this to advise you that your statement is not correct.
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Andrew, I hope I'm about to explain some things you already know. But it's not at all clear from your posts that you do understand this stuff.

Up to 10m, nothing has to be supported under tension *at all* because it's all happening at positive pressure.



 

Offline rosy

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Re: How do Trees Really lift Water to their Leaves?
« Reply #147 on: 21/09/2007 13:00:01 »
Sorry. It was a siphon in 2005 and it still is.
It still doesn't explain anything that wasn't better explained before.
And I have too little free time to go round the houses on this one with you. Again.

On second thoughts, I'm a sucker for an obvious explanation...

You have added n mL of a denser solution to your dilute solution. Say the density is 2 g/mL rather than 1 then thats added n g extra weight to the "down" arm.
All the water in the "up" and "down" arms is balanced from one side to the other so say your max tube height is 20 m and you inject 10 mL salt solution (weight 20 g), you've just aquired the ability *by siphoning* to lift 10 g, and therefore 10 mL water 20 m up. If the surface of the water under your your "down" arm were 1 m higher up than the surface of the water under your "up" arm I'd expect to see you siphon 200 mL water. If they're only 10 cm different in height it would be 10 times that, so 2 L water. If they were at the same height limiting factors would be things like friction as you're not actually lifting any water that isn't counterbalanced by water on the other side going down.
I can't see the heights of the containers on the Brixham cliffs experiment, but the scaled down version seems to show about 2 mL salt solution, so maybe 2 g of weight falling maybe 1 m, and two containers at near-as-dammit the same height (say 1 cm different), and maybe 3 mL water transferred across.
So you've got enough energy out of your SIPHON to move 2 mL water up 1 m (OK, maybe a bit less, depending on how concentrated your salt solution is) but you're actually lifting about 4 mL up about 1 cm, using maybe 2 % of the energy available from the conventional-physics based explantion in terms of a siphon.
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #148 on: 21/09/2007 16:48:36 »
Thank you for the reply Rosy, Ill try to get my head around your post in a bit, but the question that tension does not exist inside the inverted loop of tubing is dismissed because the salt solution is not initially injected into the tube but the syringe plunger together with the salt solution, which is hanging upside down is drawn into the loop of tubing by a negative tension which you said does not exist in your earlier post.

To activate this flow system all that is required is one grain / crystal of salt or sugar in one side, this induces the water filled loop of tubing to circulate. Even half a single crystal would do it. If you look at the other video showing salt crystals dropping into a clear water filled container you can see the flow generated by individual falling crystals as they dissolve, the sunlight shows the current created by this system.

there is no height difference between either of the bottles, the tubes are placed at the bottom of the two bottles. The recipient bottle overflows, the donor bottle level goes down rapidly as water is transferred from one vessel to the other, the displaced water = many times the volume of the added salt solution and should equate to the contents of the donor side of the tube. Which incidentally can be much larger in diameter than the downward flowing side. I have used an additional juxtaposed tube in the donor side to prove this capability and it runs perfectly. I did this to show that the flow is capable of delivering sufficient sap to the leaves to allow for the huge evaporation, which is known to take place at the leaf.

Changing the height of the arms as you put it at 24 metres does not induce a flow through siphoning. Possibly, the elasticity of water prevents this causing the bead of water to break and then water in both sides of the tube irrespective of the differences in levels will fall to the 10 metre level and the space above the water levels is vacuum.

This flow is different from a siphon effect. Because the water molecules are connected and under tension, by cohesion, the first denser molecule descends causing a chain reaction along the entire tube which drags all of the other molecules around much the same as if the water bead were made of elastic.
 
Andrew
 

Offline Andrew K Fletcher

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Re: How do Trees Really lift Water to their Leaves?
« Reply #149 on: 15/01/2008 11:36:57 »
Umbrella Plant Experiment 
Cyperus alternifolius

Take a stem of this plant approximately 6-8 inches place it upside down in a beaker / vase of water and ignore for around 2 months. The roots begin to grow from the crown of the leaves, followed by the ascending leaves from the developing root crown. Gravitropism is the term used to explain how plants and trees determine the correct orientation in relation to gravity. However, I believe that the migration of denser solutes to the leaf crown due to the plant being kept upside down plays a very important part in this process.






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Re: How do Trees Really lift Water to their Leaves?
« Reply #149 on: 15/01/2008 11:36:57 »

 

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