Fix C3 and C4 assignment in Ryan 1991 leaf maintenance respiration model

[JessicaNeedham]

This PR fixes the incorrect C3 assignment in the Ryan 1991 leaf maintenance respiration model. It also changes the LeafLayerBiophysicalRates subroutine to put the C3/C4 temperature sensitivity code in an if else statement.

This PR addresses issue #1052 .

Collaborators:

@rgknox
@glemieux

Expectation of Answer Changes:

This PR will change answers if the leaf maintenance respiration model is set to Ryan 1991, as C3 and C4 temperature sensitivity will be reversed.

Checklist:

• My change requires a change to the documentation.
• I have updated the in-code documentation .AND. (the technical note .OR. the wiki) accordingly.
• [ x] I have read the CONTRIBUTING document.
• FATES PASS/FAIL regression tests were run
• If answers were expected to change, evaluation was performed and provided

Test Results:

Code compiles on Perlmutter but no other testing.

CTSM (or) E3SM (specify which) test hash-tag:

CTSM (or) E3SM (specify which) baseline hash-tag:

FATES baseline hash-tag:

Test Output:

[rgknox]

Awesome

[JessicaNeedham]

The way the LeafLayerBiophysicalRates had been written jmax was adjusted in both c3 and c4 plants, and then c4 plants had additional adjustments to vcmax. Does the jmax belong outside of the c3/c4 if else statement?

[glemieux]

Regression testing underway on Cheyenne

[rgknox]

yes, agreed, good catch regarding the jmax fix @JessicaNeedham

[glemieux]

All expected tests PASS on cheyenne against fates-sci.1.66.2_api.25.5.0-ctsm5.1.dev130. All fates tests result in DIFFs since the Ryan model is the default respiration for all test modes. Checking the AllVars test shows that the only difference during the first time step is FATES_NET_C_UPTAKE_CLLL which makes sense since it is calculated immediately after the maintenance respiration calculation. All other differences appear to be downstream of this as they occur on the next time step.

Generated baseline fates-sci.1.66.3_api.25.5.0-ctsm5.1.dev130.