Changes between Version 92 and Version 93 of Documentation/TrunkFunctionality4

Timestamp:

2021-03-31T17:41:32+02:00 (3 years ago)

Author:

luyssaert

Comment:

--

Documentation/TrunkFunctionality4

@@ -393 +393 @@
 The regulation is smoothened by setting boundaries to avoid sudden decreases in GPP (which are not apparent in the data). Smoothing is taken care of in stomate_vmax.f90. If the plant has less carbon in its labile and carbres pools than wanted, the NUE is upregulated. Up regulation is also capped to avoid crazy NUE values and high frequency changes between up and downregulation. Up and downregulation are done in stomate_vmax.f90. The parameters than control the smoothing are '''sugar_load_min''' and '''sugar_load_max''' and can be set in the run.def.
 
+Sugar loading can have a huge effect on the GPP even up to the point that realist LAIs come with way too low GPPs. This issues was eventually solved by setting the roots, leaves and sapwood longivity to observed values (for sapwood turnover this is not a very well constrainted parameter). Most important is to aim for a good NPP/GPP ratio. Interestingly when approaching the values reported in Campiolli et al 2015 and Vicca et al 2012, the reserves drop to more realistic values. At this point sugar loading is becoming much less dominant. From r7135 onwards, sugar loading cannot reduce the GPP by more than 25%. This implies that reserves could become crazy again and should be monitored regularly. 
+
 
 === Recruitment ===