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davidjpmoore / WUE_ci

A repository to explore the year by year effect of rising CO2 on potential photosynthesis given ci of tree rings
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Calculate stomatal limitation L for range of J conditions #3

Open davidjpmoore opened 6 years ago

davidjpmoore commented 6 years ago

Calculate the stomatal limitation for photosynthesis for each canopy position light level

davidjpmoore commented 6 years ago

Full Harvard record provides a range of realistic PAR values Calculating J using Jmax from Griffen pers comm and J = (jmax +PhiPAR - sqrt((jmax+PhiPAR)^2-4thetajmaxPhiPAR))/2*theta

Equation 1(a) from Walker 2014 modified from Farquhar and Wong 1984

image Results in this response curve: image

Canopy light study from Harvard Forest (David Foster) image

Driving equation 1(a) Results in the following J calculations image

This is summarized here: image

Most of the time ... it's dark image

if you think about it isotopically ... most of the signal should be made up from periods when photosynthesis is actually happening ... at really low light, the overall isotopic signal is probably not being changed. I'll need to think about how to deal with this