The Mystery of the Disappearing Lake

http://tncweeds.ucdavis.edu/photos/phrau05.jpg

Phragmites austalis

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Phragmites

http://www.ucmp.berkeley.edu/IB181/VPL/Ana/AnaP/Ana22l.jpeg

Phragmites

http://www.ucmp.berkeley.edu/IB181/VPL/Ana/AnaP/Ana22l.jpeg

Stomata

Phragmites

Phragmites

Water loss

Transpiration

Phragmites

Transpiration

Water uptake through roots

Water uptake through roots

So… why is transpiration higher in Phragmites than native species?

So… why is transpiration higher in Phragmites than native species?

• Stem density

So… why is transpiration higher in Phragmites than native species?

• Stomatal density

Stomata

So… why is transpiration higher in Phragmites than native species?

• Stomatal regulation

So… why is transpiration higher in Phragmites than native species?

• Dense root system

Detritus: Another piece of the puzzle

• Detritus is dead organic material from plants or animals

• Detritus from Phragmites is very slow to degrade

• Why might that cause the lake to get smaller?

Detritus: Another piece of the puzzle

• As detritus accumulates it starts to fill in the lake and raise the level of the land above the water level