150 | | There are no options to revert to the allocation based on resource limitation. All references and parameters for allocation based on resource limitation have been removed from the code (those that were overlloked can be removed). Allometric allocation makes use of the following PFT-specific parameters: '''sla''', '''tau_root''', '''tau_leaf''', '''tau_sap''', '''pipe_density''', '''tree_ff''', '''pipe_tune_x''', '''k_latosa_max''', and '''k_latosa_min'''. In addition to this set of parameters that mainly describe the allometric relationships and the longevity of the different tissues, the calculation of the allocation coefficients makes use PFT-specific tissue conductivities, i.e., '''k_sap''', '''k_root''', and '''k_leaf''' (see also plant water stress). As such there is a functional link between C and N-allocation and the hydraulic architecture of a plant. Details on the parameters can be found in the SI of Naudts et al 2015 in GMD or in src_parameters/constantes_mtc.f90. |
| 150 | There are no options to revert to the allocation based on resource limitation. All references and parameters for allocation based on resource limitation have been removed from the code (those that were overlooked can be removed). Allometric allocation makes use of the following PFT-specific parameters: '''sla''', '''tau_root''', '''tau_leaf''', '''tau_sap''', '''pipe_density''', '''tree_ff''', '''pipe_tune_x''', '''k_latosa_max''', and '''k_latosa_min'''. In addition to this set of parameters that mainly describe the allometric relationships and the longevity of the different tissues, the calculation of the allocation coefficients makes use PFT-specific tissue conductivities, i.e., '''k_sap''', '''k_root''', and '''k_leaf''' (see also plant water stress). As such there is a functional link between C and N-allocation and the hydraulic architecture of a plant. Details on the parameters can be found in the SI of Naudts et al 2015 in GMD or in src_parameters/constantes_mtc.f90. |
173 | 173 | * OOL_SEC_STO_FG4: ~0.5x0.5 degrees annual CRU-NCEP forcing between 1901 and 2010. Start from scratch. 64 PFTs, European forest are defined at the species level with 4 age classes, forests outside of Europe are defined at the MTC level with 1 age class, annual land cover and tree species changes, annual input deposition, annual CO2 concentrations, annual forest management, and annual litter raking. |
174 | 174 | * OOL_SEC_STO_FG5: 1x1 degrees annual IPSL RCP 4.5 forcing between 1911 and 2100. Start from OOL_SEC_STO_FG4. XX PFTs, no land cover and changes, annual input deposition, annual CO2 concentrations, prescribed species and management changes following annual a stand replacing disturbance, litter raking for 2010. This configuration is under development. Waiting for the boundary files to be copied to orchideeshare. The species and management change functionality needs to be tested within CN-CAN. |
245 | | Land cover change now accounts for age classes. It is controlled by the flags '''land_cover_change''' and '''veget_update'''. Set '''land_cover_change''' = n and '''veget_update''' = 0Y if land cover change should be disabled. The wood pool and its subsequent fluxes were moved from the land cover change routine to a separate routine. Furthermore, land cover change also deals with the change of biological land uses to non biological land uses (of which the most important change is probably urbanization). If urbanization happens, all the carbon an nitrogen are stored in a series of variables '''burried_xxx''' where xxx stands for a different pool, e.g., litter, soil, .... Burried_xxx are cumulative variables thus increasing over time. There is a place holder in sapiens_lcchange.90 to also develop the release of the burried carbon and nitrogen following de-urbanization (see ticket #616). The series of the burried_xxx variables are not yet written to an output file but this could be easily added. |
246 | | |
247 | | An interesting parameter is '''min_vegfrac'''. When reading in a land cover map, PFTs with a fraction below min_vegfrac are removed. Likewise the fraction cover of a PFT after a land cover change should not be less than min_vegfrac either. This requirement seems to have been solely established to avoid ending up with too many PFTs with very small fractions. Because the the non-biological and biological fraction covers of each pixel should sum up to one, removing even these very small fractions implies that these farctions need to be added to one of the remaining PFTs. First it is tried to add the fraction to the bare soil (this will only be accepted if the new fraction of the bare soil exceeds min_vegfrac), then the code tries to allocate the residual fraction to the largest vegetated fraction. If age classes are used this should be the largest vegetated fraction in the first age class of a PFT. If all of the above failed, the residual fraction is added to frac_nobio irrespective of whether frac_nobio exceeds min_vegfrac. Everytime this happens, the failure to meet the min_vegfrac criterion is registered in the variable '''failed_vegfrac'''. This variable is not yet added to an output file. |
| 245 | Land cover change now accounts for age classes. It is controlled by the flags '''land_cover_change''' and '''veget_update'''. Set '''land_cover_change''' = n and '''veget_update''' = 0Y if land cover change should be disabled. The wood pool and its subsequent fluxes were moved from the land cover change routine to a separate routine. Furthermore, land cover change also deals with the change of biological land uses to non biological land uses (of which the most important change is probably urbanization). If urbanization happens, all the carbon an nitrogen are stored in a series of variables '''burried_xxx''' where xxx stands for a different pool, e.g., litter, soil, .... Burried_xxx are cumulative variables thus increasing over time. There is a place holder in sapiens_lcchange.90 to also develop the release of the buried carbon and nitrogen following de-urbanization (see ticket #616). The series of the burried_xxx variables are not yet written to an output file but this could be easily added. |
| 246 | |
| 247 | An interesting parameter is '''min_vegfrac'''. When reading in a land cover map, PFTs with a fraction below min_vegfrac are removed. Likewise the fraction cover of a PFT after a land cover change should not be less than min_vegfrac either. This requirement seems to have been solely established to avoid ending up with too many PFTs with very small fractions. Because the the non-biological and biological fraction covers of each pixel should sum up to one, removing even these very small fractions implies that these fractions need to be added to one of the remaining PFTs. First it is tried to add the fraction to the bare soil (this will only be accepted if the new fraction of the bare soil exceeds min_vegfrac), then the code tries to allocate the residual fraction to the largest vegetated fraction. If age classes are used this should be the largest vegetated fraction in the first age class of a PFT. If all of the above failed, the residual fraction is added to frac_nobio irrespective of whether frac_nobio exceeds min_vegfrac. Everytime this happens, the failure to meet the min_vegfrac criterion is registered in the variable '''failed_vegfrac'''. This variable is not yet added to an output file. |
315 | | The pft-specific parameter '''always_init''' controls whether the phenology depends on the reserves (set to .FALSE.) or is forced (set to .TRUE.). Note that a forced phenology (thus always_init = .TRUE.) has no ecophysiological basis, it is a numerical approach to stabilize the vegetation cover. A stable vegetation cover is particulary welcome in coupled simulations but likley hides real vegetation dynamics (especially under future climate conditions) or problems in other routines or parameter settings. If a PFT keeps dying in an area where it is currently present, this would hint at a problem with the current model/parameters. If a PFT keeps dying under future conditions, it may be a real response (depending on the PFT). If forced phenology is used, plants will develop an initial canopy in phenology irrespective of whether the plant had sufficient carbon and nitrogen reserves and for evergreen species irrespective of whether the canopy was viable at all. This setting basically overcomes a mortality event at the expense of taking up carbon and nitrogen from the atmosphere. When used in combination with impose_cn = n, an inconsistency is introduced: impose_cn = n reflect the desire to close the nitrogen cycle, always_init = y opens a backdoor in the nitrogen cycle. |
316 | | |
317 | | From a conceptual point of view, CN-CAN is all about vegetation dynamics and thus instabilities in the vegetation cover. In CN-CAN there are two processes that can deal with dying PFts including evergreens PFTs. First, ok_recruitment could used. If ok_recruitment = .TRUE. a decreas in the canopy cover will result in more light reaching the forest floor which in turn should trigger recruitment of -for the moment- the same PFT. Generation can take over from each other without loosing the canopy cover entirely. Second, if there are insufficient reserves to grow no leaves, there will be no or insufficient gpp, the crabon reserves will be consumed by respiration processes, the plants will be killed, the biomass transferred to the litter pools and the same or another PFT (see section on species change) will be replanted. CN-CAN was developed to work with always_init = .FALSE. so this has become the default value, contrary to the trunk where always_init = .TRUE. is the default. |
| 315 | The pft-specific parameter '''always_init''' controls whether the phenology depends on the reserves (set to .FALSE.) or is forced (set to .TRUE.). Note that a forced phenology (thus always_init = .TRUE.) has no ecophysiological basis, it is a numerical approach to stabilize the vegetation cover. A stable vegetation cover is particularly welcome in coupled simulations but likley hides real vegetation dynamics (especially under future climate conditions) or problems in other routines or parameter settings. If a PFT keeps dying in an area where it is currently present, this would hint at a problem with the current model/parameters. If a PFT keeps dying under future conditions, it may be a real response (depending on the PFT). If forced phenology is used, plants will develop an initial canopy in phenology irrespective of whether the plant had sufficient carbon and nitrogen reserves and for evergreen species irrespective of whether the canopy was viable at all. This setting basically overcomes a mortality event at the expense of taking up carbon and nitrogen from the atmosphere. When used in combination with impose_cn = n, an inconsistency is introduced: impose_cn = n reflect the desire to close the nitrogen cycle, always_init = y opens a backdoor in the nitrogen cycle. |
| 316 | |
| 317 | From a conceptual point of view, CN-CAN is all about vegetation dynamics and thus instabilities in the vegetation cover. In CN-CAN there are two processes that can deal with dying PFts including evergreens PFTs. First, ok_recruitment could used. If ok_recruitment = .TRUE. a decrease in the canopy cover will result in more light reaching the forest floor which in turn should trigger recruitment of -for the moment- the same PFT. Generation can take over from each other without loosing the canopy cover entirely. Second, if there are insufficient reserves to grow no leaves, there will be no or insufficient gpp, the carbon reserves will be consumed by respiration processes, the plants will be killed, the biomass transferred to the litter pools and the same or another PFT (see section on species change) will be replanted. CN-CAN was developed to work with always_init = .FALSE. so this has become the default value, contrary to the trunk where always_init = .TRUE. is the default. |
390 | | * '''ok_mleb:''' Flag that activates the multilayer energy budget (true/false). The model uses 10 (default) canopy layers to calculate the albedo, transmittance, absorbance and GPP. These canopy layers can be combined with 10 (default) layers below and 9 layers above the canopy to calculate the energy budget (ok_mleb=y). If set to no, this flag will make the model use 10 layers for the canopy albedo, transmittance, absorbance and GPP and just a single layer for the energy budget. Be aware that if you wish to run with hydraulic architechture ok_mleb needs to be se to true as well. Furthermore, if you wish to run with the original energy scheme (enerbil), set the layers for mleb to 1. |
| 390 | * '''ok_mleb:''' Flag that activates the multilayer energy budget (true/false). The model uses 10 (default) canopy layers to calculate the albedo, transmittance, absorbance and GPP. These canopy layers can be combined with 10 (default) layers below and 9 layers above the canopy to calculate the energy budget (ok_mleb=y). If set to no, this flag will make the model use 10 layers for the canopy albedo, transmittance, absorbance and GPP and just a single layer for the energy budget. Be aware that if you wish to run with hydraulic architecture ok_mleb needs to be se to true as well. Furthermore, if you wish to run with the original energy scheme (enerbil), set the layers for mleb to 1. |
571 | | || '''Process''' || '''Parameter(s)''' || '''Tool''' || |
572 | | || Onset of growing season and start of senescence || thresholds for phenology || FLUXNET || |
573 | | || NPP/GPP ratio || coeff for maintenance respiration || FLUXNET + Campioli || |
574 | | || Magnitude of LAI || k_latosa_min and k_latosa_max || NFI + Luyssaert et al 2007 || |
575 | | || Magnitude of GPP || LL_alpha, Vcmax, J_max || FLUXNET || |
576 | | || Magnitude of NPP || Implicit through NPP/GPP and GPP || Luyssaert et al 2007 || |
577 | | || Evapotranspiration || LAI_top, water stress || FLUXNET || |
578 | | || Water stress || To be discovered || FLUXNET || |
579 | | || Magnitude of Rh || To be checked - Rh || Luyssaert et al 2007 || |
580 | | || Magnitude of TER || To be checked - Rh || FLUXNET || |
581 | | || Diameter, height, and biomass || form factor || NFI + Luyssaert et al 2007 || |
582 | | || Density and biomass || self-thinning parameters || NFI + Luyssaert et al 2007 || |
583 | | || Harvest and biomass || Self-thinning and RDI parameters || NFI + ??? || |
584 | | || Albedo || Implicit through LAI and forest structure || FLUXNET? || |
585 | | || Tree ring width || Self-thinning, recruitment || ITRDB or VERIFY Fig 4 || |
| 571 | || '''Process''' || '''Parameter(s) to tune''' || '''Data''' || '''Status''' || |
| 572 | || Onset of growing season and start of senescence || thresholds for phenology || FLUXNET || || |
| 573 | || NPP/GPP ratio || coeff for maintenance respiration || FLUXNET + Campioli || || |
| 574 | || Magnitude of LAI || k_latosa_min and k_latosa_max || NFI + Luyssaert et al 2007 || || |
| 575 | || Magnitude of GPP || LL_alpha, Vcmax, J_max || FLUXNET || || |
| 576 | || Magnitude of NPP || Implicit through NPP/GPP and GPP || Luyssaert et al 2007 || || |
| 577 | || Evapotranspiration || LAI_top, water stress || FLUXNET || || |
| 578 | || Water stress || k_root, k_sap, k_leaf, psi_leaf_min || FLUXNET || || |
| 579 | || Magnitude of Rh || To be checked - Rh || Luyssaert et al 2007 || || |
| 580 | || Magnitude of TER || To be checked - Rh || FLUXNET || || |
| 581 | || Diameter, height, and biomass || form factor, tau_sap, tau_spa, tau_root, density, pipe_tune2, pipe_tune3 || NFI + Luyssaert et al 2007 || || |
| 582 | || Stand density and biomass || self-thinning parameters || NFI + Luyssaert et al 2007 || || |
| 583 | || Harvest and biomass || Self-thinning and RDI parameters || NFI + ??? || || |
| 584 | || Albedo || Implicit through LAI and forest structure || FLUXNET? || || |
| 585 | || Tree ring width || Self-thinning, recruitment, circ_class_dist, ncirc || ITRDB or VERIFY Fig 4 || || |