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How is it possible for tall trees to pull water to heights more than 10m?
How long a straw could Superman use?Why don't I feel pressure on my body when swimming under water?Acer saccharum (Sugar Maple) Sap & FreezingWhy does evaporation take place?How does water pressure manifest itself on the molecular level?When a diving bell is submerged in water, why must I also consider the pressure of the atmosphere?Why is steam-cooking slower at higher altitudes, where water boils at a lower temperature?$P=F/A$ and $P=rho*g*h$ give different answersConcept regarding BarometerHydrostatic pressure to measure water level
$begingroup$
Which force actually drives water so high up, since pure atmospheric pressure will only get you up to about 10 meters if you're using suction and a long straw and yet tallest trees are over 100 meters ( trees do basically have long continuous 'straws' all the way up.)
pressure water fluid-statics capillary-action osmosis
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
$endgroup$
add a comment |
$begingroup$
Which force actually drives water so high up, since pure atmospheric pressure will only get you up to about 10 meters if you're using suction and a long straw and yet tallest trees are over 100 meters ( trees do basically have long continuous 'straws' all the way up.)
pressure water fluid-statics capillary-action osmosis
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
$endgroup$
$begingroup$
Veritasium's video on this topic.
$endgroup$
– Lith
8 hours ago
1
$begingroup$
I don't know, but I note that osmotic pressure can be surprisingly large: it is quite easy to reach several atmospheres of osmotic pressure, so I guess this may have something to do with it.
$endgroup$
– Andrew Steane
6 hours ago
add a comment |
$begingroup$
Which force actually drives water so high up, since pure atmospheric pressure will only get you up to about 10 meters if you're using suction and a long straw and yet tallest trees are over 100 meters ( trees do basically have long continuous 'straws' all the way up.)
pressure water fluid-statics capillary-action osmosis
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
$endgroup$
Which force actually drives water so high up, since pure atmospheric pressure will only get you up to about 10 meters if you're using suction and a long straw and yet tallest trees are over 100 meters ( trees do basically have long continuous 'straws' all the way up.)
pressure water fluid-statics capillary-action osmosis
pressure water fluid-statics capillary-action osmosis
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
edited 6 hours ago
Qmechanic♦
110k12 gold badges211 silver badges1295 bronze badges
110k12 gold badges211 silver badges1295 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
asked 9 hours ago
Leo KovacicLeo Kovacic
774 bronze badges
774 bronze badges
$begingroup$
Veritasium's video on this topic.
$endgroup$
– Lith
8 hours ago
1
$begingroup$
I don't know, but I note that osmotic pressure can be surprisingly large: it is quite easy to reach several atmospheres of osmotic pressure, so I guess this may have something to do with it.
$endgroup$
– Andrew Steane
6 hours ago
add a comment |
$begingroup$
Veritasium's video on this topic.
$endgroup$
– Lith
8 hours ago
1
$begingroup$
I don't know, but I note that osmotic pressure can be surprisingly large: it is quite easy to reach several atmospheres of osmotic pressure, so I guess this may have something to do with it.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
Veritasium's video on this topic.
$endgroup$
– Lith
8 hours ago
$begingroup$
Veritasium's video on this topic.
$endgroup$
– Lith
8 hours ago
1
1
$begingroup$
I don't know, but I note that osmotic pressure can be surprisingly large: it is quite easy to reach several atmospheres of osmotic pressure, so I guess this may have something to do with it.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
I don't know, but I note that osmotic pressure can be surprisingly large: it is quite easy to reach several atmospheres of osmotic pressure, so I guess this may have something to do with it.
$endgroup$
– Andrew Steane
6 hours ago
add a comment |
2 Answers
2
active
oldest
votes
$begingroup$
It's not only atmospheric pressure which is involved in water delivery to a tree, but mainly the capillary action and osmosis.
Osmosis and Hydrostatic Pressure
Roots take advantage of "pressures" when water and its solutions are unequal. The key to remember about osmosis is that water flows from the solution with the lower solute concentration (the soil) into the solution with higher solute concentration (the root).
Water tends to move to regions of negative hydrostatic pressure gradients. Water uptake by plant root osmosis creates a more negative hydrostatic pressure potential near the root surface. Tree roots sense water (less negative water potential) and growth is directed towards water (hydrotropism).
(From “Process of How Trees Absorb and Evaporate Water via Roots and Leaves”, ThoughCo.)
Only for the sake of your interest:
Current hypotheses of height limitation focus on increasing water transport constraints in taller trees and the resulting reductions in leaf photosynthesis. We studied redwoods (Sequoia sempervirens), including the tallest known tree on Earth (112.7 m), in wet temperate forests of northern California.
Our regression analyses of height gradients in leaf functional characteristics estimate a maximum tree height of 122–130 m barring mechanical damage, similar to the tallest recorded trees of the past. As trees grow taller, increasing leaf water stress due to gravity and path length resistance may ultimately limit leaf expansion and photosynthesis for further height growth, even with ample soil moisture.
(From Koch, George W.; Sillett, Stephen C.; Jennings, Gregory M.; Davis, Stephen D.: “The limits to tree height”. Nature. 428 (6985): 851–854.)
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
$endgroup$
add a comment |
$begingroup$
It due to transpiration pull. Due to which is water molecules experience a force that pulls it upwards.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
1
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
add a comment |
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2 Answers
2
active
oldest
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2 Answers
2
active
oldest
votes
active
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votes
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votes
$begingroup$
It's not only atmospheric pressure which is involved in water delivery to a tree, but mainly the capillary action and osmosis.
Osmosis and Hydrostatic Pressure
Roots take advantage of "pressures" when water and its solutions are unequal. The key to remember about osmosis is that water flows from the solution with the lower solute concentration (the soil) into the solution with higher solute concentration (the root).
Water tends to move to regions of negative hydrostatic pressure gradients. Water uptake by plant root osmosis creates a more negative hydrostatic pressure potential near the root surface. Tree roots sense water (less negative water potential) and growth is directed towards water (hydrotropism).
(From “Process of How Trees Absorb and Evaporate Water via Roots and Leaves”, ThoughCo.)
Only for the sake of your interest:
Current hypotheses of height limitation focus on increasing water transport constraints in taller trees and the resulting reductions in leaf photosynthesis. We studied redwoods (Sequoia sempervirens), including the tallest known tree on Earth (112.7 m), in wet temperate forests of northern California.
Our regression analyses of height gradients in leaf functional characteristics estimate a maximum tree height of 122–130 m barring mechanical damage, similar to the tallest recorded trees of the past. As trees grow taller, increasing leaf water stress due to gravity and path length resistance may ultimately limit leaf expansion and photosynthesis for further height growth, even with ample soil moisture.
(From Koch, George W.; Sillett, Stephen C.; Jennings, Gregory M.; Davis, Stephen D.: “The limits to tree height”. Nature. 428 (6985): 851–854.)
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
$endgroup$
add a comment |
$begingroup$
It's not only atmospheric pressure which is involved in water delivery to a tree, but mainly the capillary action and osmosis.
Osmosis and Hydrostatic Pressure
Roots take advantage of "pressures" when water and its solutions are unequal. The key to remember about osmosis is that water flows from the solution with the lower solute concentration (the soil) into the solution with higher solute concentration (the root).
Water tends to move to regions of negative hydrostatic pressure gradients. Water uptake by plant root osmosis creates a more negative hydrostatic pressure potential near the root surface. Tree roots sense water (less negative water potential) and growth is directed towards water (hydrotropism).
(From “Process of How Trees Absorb and Evaporate Water via Roots and Leaves”, ThoughCo.)
Only for the sake of your interest:
Current hypotheses of height limitation focus on increasing water transport constraints in taller trees and the resulting reductions in leaf photosynthesis. We studied redwoods (Sequoia sempervirens), including the tallest known tree on Earth (112.7 m), in wet temperate forests of northern California.
Our regression analyses of height gradients in leaf functional characteristics estimate a maximum tree height of 122–130 m barring mechanical damage, similar to the tallest recorded trees of the past. As trees grow taller, increasing leaf water stress due to gravity and path length resistance may ultimately limit leaf expansion and photosynthesis for further height growth, even with ample soil moisture.
(From Koch, George W.; Sillett, Stephen C.; Jennings, Gregory M.; Davis, Stephen D.: “The limits to tree height”. Nature. 428 (6985): 851–854.)
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
$endgroup$
add a comment |
$begingroup$
It's not only atmospheric pressure which is involved in water delivery to a tree, but mainly the capillary action and osmosis.
Osmosis and Hydrostatic Pressure
Roots take advantage of "pressures" when water and its solutions are unequal. The key to remember about osmosis is that water flows from the solution with the lower solute concentration (the soil) into the solution with higher solute concentration (the root).
Water tends to move to regions of negative hydrostatic pressure gradients. Water uptake by plant root osmosis creates a more negative hydrostatic pressure potential near the root surface. Tree roots sense water (less negative water potential) and growth is directed towards water (hydrotropism).
(From “Process of How Trees Absorb and Evaporate Water via Roots and Leaves”, ThoughCo.)
Only for the sake of your interest:
Current hypotheses of height limitation focus on increasing water transport constraints in taller trees and the resulting reductions in leaf photosynthesis. We studied redwoods (Sequoia sempervirens), including the tallest known tree on Earth (112.7 m), in wet temperate forests of northern California.
Our regression analyses of height gradients in leaf functional characteristics estimate a maximum tree height of 122–130 m barring mechanical damage, similar to the tallest recorded trees of the past. As trees grow taller, increasing leaf water stress due to gravity and path length resistance may ultimately limit leaf expansion and photosynthesis for further height growth, even with ample soil moisture.
(From Koch, George W.; Sillett, Stephen C.; Jennings, Gregory M.; Davis, Stephen D.: “The limits to tree height”. Nature. 428 (6985): 851–854.)
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
$endgroup$
It's not only atmospheric pressure which is involved in water delivery to a tree, but mainly the capillary action and osmosis.
Osmosis and Hydrostatic Pressure
Roots take advantage of "pressures" when water and its solutions are unequal. The key to remember about osmosis is that water flows from the solution with the lower solute concentration (the soil) into the solution with higher solute concentration (the root).
Water tends to move to regions of negative hydrostatic pressure gradients. Water uptake by plant root osmosis creates a more negative hydrostatic pressure potential near the root surface. Tree roots sense water (less negative water potential) and growth is directed towards water (hydrotropism).
(From “Process of How Trees Absorb and Evaporate Water via Roots and Leaves”, ThoughCo.)
Only for the sake of your interest:
Current hypotheses of height limitation focus on increasing water transport constraints in taller trees and the resulting reductions in leaf photosynthesis. We studied redwoods (Sequoia sempervirens), including the tallest known tree on Earth (112.7 m), in wet temperate forests of northern California.
Our regression analyses of height gradients in leaf functional characteristics estimate a maximum tree height of 122–130 m barring mechanical damage, similar to the tallest recorded trees of the past. As trees grow taller, increasing leaf water stress due to gravity and path length resistance may ultimately limit leaf expansion and photosynthesis for further height growth, even with ample soil moisture.
(From Koch, George W.; Sillett, Stephen C.; Jennings, Gregory M.; Davis, Stephen D.: “The limits to tree height”. Nature. 428 (6985): 851–854.)
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
edited 8 hours ago
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
answered 8 hours ago
MarianDMarianD
9151 gold badge6 silver badges12 bronze badges
9151 gold badge6 silver badges12 bronze badges
add a comment |
add a comment |
$begingroup$
It due to transpiration pull. Due to which is water molecules experience a force that pulls it upwards.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
1
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
add a comment |
$begingroup$
It due to transpiration pull. Due to which is water molecules experience a force that pulls it upwards.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
1
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
add a comment |
$begingroup$
It due to transpiration pull. Due to which is water molecules experience a force that pulls it upwards.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
$endgroup$
It due to transpiration pull. Due to which is water molecules experience a force that pulls it upwards.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
answered 7 hours ago
Tushar soniTushar soni
11 bronze badge
11 bronze badge
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Tushar soni is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
1
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
add a comment |
1
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
1
1
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
Please could you say what "transpiration pull" is. The name alone is of rather limited help.
$endgroup$
– Andrew Steane
6 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
This does not provide an answer to the question. Once you have sufficient reputation you will be able to comment on any post; instead, provide answers that don't require clarification from the asker. - From Review
$endgroup$
– Cosmas Zachos
2 hours ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
$begingroup$
@AndrewSteane #4 here: cropsreview.com/transpiration-pull.html
$endgroup$
– safesphere
1 hour ago
add a comment |
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$begingroup$
Veritasium's video on this topic.
$endgroup$
– Lith
8 hours ago
1
$begingroup$
I don't know, but I note that osmotic pressure can be surprisingly large: it is quite easy to reach several atmospheres of osmotic pressure, so I guess this may have something to do with it.
$endgroup$
– Andrew Steane
6 hours ago