How Do Trees Absorb Nutrients and Survive Winter?

[256bits]

May I inject a related question please? I've searched books about trees without finding this answer.

How do the nutrients formed by photosynthesis is the leaves get transported down to the trunk and the roots? Actually, I'm thinking of molecules more than complex nutrients. The trunk and roots have lots of carbon that I think was captured from the atmosphere. I'm trying to imagine how it got down there from the leaves.

Wiki once more.
Actually nutrients will travel either way, or sometimes both ways, both ways depending upon where the tree is in its growing season.
https://en.wikipedia.org/wiki/Phloem

 

[anorlunda]

phloem

https://en.wikipedia.org/wiki/Phloem

Thank you both. Phloem was the key word I lacked. The wiki article helped.

I'm curious if anyone has done a very physics-oriented non-biological-oriented experiment on trees -- a mass balance.

Let's say that a tree adds one metric ton of wood mass in one growing season. Applying conservation of mass, the mass of nutrients going up to the crown, must be at least one metric ton less than the mass of nutrients in the sap flowing down in the phloem. Measuring that mass balance would be an interesting and challenging experiment to perform. Has it been done to your knowledge?

Water makes it more challenging. The mass of water need not balance because water can be absorbed by roots and evaporate in the crown. Also, the mass of wood added in the season would have to be corrected for the water content of the new wood.

 

[votingmachine]

Thank you both. Phloem was the key word I lacked. The wiki article helped.

I'm curious if anyone has done a very physics-oriented non-biological-oriented experiment on trees -- a mass balance.

Let's say that a tree adds one metric ton of wood mass in one growing season. Applying conservation of mass, the mass of nutrients going up to the crown, must be at least one metric ton less than the mass of nutrients in the sap flowing down in the phloem. Measuring that mass balance would be an interesting and challenging experiment to perform. Has it been done to your knowledge?

Water makes it more challenging. The mass of water need not balance because water can be absorbed by roots and evaporate in the crown. Also, the mass of wood added in the season would have to be corrected for the water content of the new wood.

Plants have been grown on scales many times. The water flow you mention makes it difficult to measure the up and down differences. And a great deal if the new mass is not sent to the roots. A tree adds a new ring, branches get longer. A plant adds mass above the roots, and has water flowing continuously upward. You could easily measure root mass and mass above the surface. But I'm not sure what question you are getting at. Plants mobilize resources. That is known. It is not hard to grow plants, and weigh them, either cut up or whole.

I recall a lab that was trying to use MRI on plants to track nutrient flow, but they were more focused on WHAT things are being transported, rather than mass amounts. I worked in a lab that spent a lot of time looking at the yield of corn plants, seed weight and number of seeds per ear, and how to increase those. Yield studies are definitely an important part of plant work.

 

[Edison Bias]

I'm not sure, but I don't believe photosynthesis uses UV light at all. I think it uses different parts of the visible spectrum depending on the exact pigments used.

Hi Drakkith, I just found this in your article about photosythesis:

"Most organisms that utilize photosynthesis to produce oxygen use visible light to do so"

So I was wrong in my assumption.

Edison

 

[Hornbein]

It isn't suction or capillary action. Tree cells actively pump water.

 

[jim hardy]

It isn't suction or capillary action. Tree cells actively pump water.

I'd sure love to read about that.
It might validate my long held but utterly baseless opinion that alternate tension/compression{think deflection in a beam) as they sway in the breeze provides the motive force.

 

[Hornbein]

I'd sure love to read about that.
It might validate my long held but utterly baseless opinion that alternate tension/compression{think deflection in a beam) as they sway in the breeze provides the motive force.

I learned it when earning my biology degree.

 

[jim hardy]

Can you describe the mechanism ?

 

[Edison Bias]

I'm sorry to disturb you in that interesting discussion but I just wish to say something. I have read some of Drakkith nicely provided wiki-link about phosynthesis. It describes the situation of free electrons. I don't really understand it but it got me thinking of the photo-electric effect. Is it perhaps this that is going on in the leaves? A photon splits the ionic chemical bound in Carbondioxide into Carbon and Oxygen, another photon then separates Hydrogen from the Oxygen in water and together in special doses they form Sugar and Oxygen. I think it is extremely interesting that except for the amazing Oxygen, photosynthesis produce Sugar to give the plant energy to sustain life. The rest of growth is made by extracting nutricians from the ground. What does this tell us, sometimes fat people like me that sit on our asses most of the time? Maybe we should not consume so much sugar because it is pure energy :)

Edison

 

[jim hardy]

Maybe we should not consume so much sugar because it is pure energy :)

Off topic

Do you notice sugar affecting your mood?
Search on these terms : diabetes obesity sugar LCHF ketosis

There is a growing school of thought that US consumption rate of sugar is a danger to public health.

I just bought myself a $20 blood sugar test kit at Walmart.

 

[Edison Bias]

Thank you for your reply, Jim!

More off topic, if I may?

I am a dedicated fan of LCHF which I think is based on the way cavemen ate (and who has "seen" a fat caveman?). I also think that what you call ketosis goes something like this: If you cancel the corbonhydroxides (CH) in your food, the cells switch from burning CH to burning fat. My thought about this is the that while they are saying that there are two kinds of CH (i.e fast/slow) both contains exactly the same amount of energy and CH is CH regardless if there are parts of it that is called sugar (of different names). The only difference is the rate of sugar "shock" to the sugar regulating system (i.e insulin production). And look at a person about to run Marathon, what does he/she eat? Yes, they eat pasta i.e slow CH. And run for 50km...

All this while I hardly even run for the bus :D

Edison
PS
I really do not experience moodswings due to sugar. If I experience anything it's more like nausea due to too much sugar. I have never experienced less of tiredness. Coffee works better :)

 

[Evo]

It seems this thread has gone off topic and the question about trees has been answered, so we will close this thread.