Changes between Version 64 and Version 65 of Documentation/TrunkFunctionality4

Timestamp:

2020-10-28T11:19:20+01:00 (4 years ago)

Author:

jjeong

Comment:

--

Documentation/TrunkFunctionality4

@@ -166 +166 @@
 
 === Equifinality ===
-XXX
-
+'''LAI'''
+* k_latosa \\
+   Tested with r6818, PFT4. A nonlinear relationship between '''k_latosa''' and annual mean LAI was found. LAI saturated when k_latosa increased: 2500 to 4500 by 500.
+* Parameter compensations \\
+   Tested with r6818, PFT4. 5 sets of parameters for PFT4 were replaced with the parameters for PFT7. \\\\
+   set1: '''k_latosa, longevity_leaf, sla''' \\
+   set2: '''arjv, vcmax25, coeff_maint_init''' \\
+   set3: '''pipe_density, pipe_tune_*, tree_ff, alloc_min''' \\
+   set4: '''psi_50, psi_leaf, k_sap, r_froot''' \\
+   set5: '''leaf_psd_*, leaf_ssa_*, bgrd_ref_*, nir, vis''' \\
+
+   Changes of set1 and set1 combined with set2 to set 5 (set1+set2, set1+set3, set1+set4 and set1+set5) increased LAI much (~2.5 -> ~7). However, change of all sets (set1+set2+set3+set4+set5) showed a moderate increase in LAI (~2.5 -> ~4) which implies parameter dependensies.
 
 === Forced clear cut ===
@@ -299 +309 @@
 
 === Nitrogen reserve pools ===
-XXX
+Describes r6904. As the carbon, the model simulates two non-structural nitrogen pools: labile and reserve. Nitrogen uptake is stored in the labile pool, and after the growth, nitrogen exceeds the calculated potential labile pool moved to reserve nitrogen. Before the r6825, nitrogen limitation during plant growth was estimated using only labile nitrogen, and this resulted in the accumulation of reserve nitrogen. To deal with this issue, the functionality considers reserve nitrogen for estimating nitrogen limitation added to the r6825. The parameter '''use_reserve_n''' controls the functionality along with nitrogen uptake feedback which was added r6869 (See [wiki:TrunkFunctionality4#Rootnitrogenuptake Root nitrogen uptake]).
 
 === Parameter files ===
@@ -360 +370 @@
 
 === Root nitrogen uptake ===
-Describes r6904. The calculation of root nitrogen uptake in nitrogen_dynamice has two parts. First, the maximum amount of root nitrogen uptake is calculated based on soil chemical properties and long-term root carbon mass. And then, nitrogen uptake is adjusted by the feedback from nitrogen reserve; if the long-term ratio of actual to potential nitrogen reserve pool is over one, then root nitrogen uptake decreases. The uptake does not decrease further than '''p_n_uptake'' of maximum root nitrogen uptake. The adjustment was added due to carbon limitation and too much nitrogen in the plant which was caused by using the reserve nitrogen as possible (See '''Nitrogen reserve pools'''), and it is controlled by the flag '''use_reserve_n''' to y.
+Describes r6904. The calculation of root nitrogen uptake in nitrogen_dynamice has two parts. First, the maximum amount of root nitrogen uptake is calculated based on soil chemical properties and long-term root carbon mass. And then, nitrogen uptake is adjusted by the feedback from nitrogen reserve; if the long-term ratio of actual to potential nitrogen reserve pool is over one, then root nitrogen uptake decreases. The uptake does not decrease further than '''p_n_uptake''' of maximum root nitrogen uptake. The adjustment was added due to carbon limitation and too much nitrogen in the plant which was caused by using the reserve nitrogen as possible (See [wiki:TrunkFunctionality4#Nitrogenreservepools Nitrogen reserve pools]), and it is controlled by the parameter '''use_reserve_n''' to y.